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title: GNU Image Manipulation Program subtitle: User Manual

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1. Preview Show preview wireframe o_ 3 o N x o e 2 8 o x gt 2 a o ww hn o c o GNU Image Manipulation Program Page 375 of 421 Generated by docbook2odf Box tab This tab appears only when you select the Box object Options Light Material Orientation Box Map Images to Box Faces Front Bi coguelicot png 1 Background 2 Back Untitled 11 Background 22 Top Untitled 1 Background 22 Bottom Untitled 11 Background 22 a x Show preview wireframe Preview Left Untitled 11 Background 22 Right Untitled 11 Background 22 Scale X 0 50 os G Y e o 50 amp m 0 G 0 50 20 Cylinder tab This tab appears only when you select the Cylinder object Options Light Material Orientation Cylinder Images for the Cap Faces Top By ntitled 11 Background 22 Bottom ___Untitled 11 Background 22 Size Radius u 0 25 Length SS p j 1 00 Q ie Preview Q x Show preview wireframe Paper Tile Overview GNU Image Manipulation Program Page 376 of 421 Generated by docbook2odf o 3 o N x e e 2 8 o 3 gt 2 a o ww hn o c o This filter is found in the image window menu under Filters Map Paper Tile This filter cuts the image
2. Common causes of GIMP non responsiveness pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 43 of 421 Generated by docbook2odf Chapter Concepts for the Intermediate GNU Image Manipulation Program Page 44 of 421 Genera ted by docbook2odf Plugins Introduction One of the nicest things about GIMP is how easily its functionality can be extended by using plugins GIMP plugins are external programs that run under the control of the main GIMP application and interact with it very closely Plugins can manipulate images in almost any way that users can Their advantage is that it is much easier to add a capability to GIMP by writing a small plugin than by modifying the huge mass of complex code that makes up the GIMP core Many valuable plugins have C source code that only comes to 100 200 lines or so Several dozen plugins are included in the main GIMP distribution and installed automatically along with GIMP Most of them can be accessed through the Filters menu in fact everything in that menu is a plugin but a number are located in other menus In many cases you Can use one without ever realizing that it is a plugin for example the Normalize function for automatic color correction is actually a plugin although there Is nothing about the way it works that would tell you this In addition to the plugins included with GIMP many more are available on the net A l
3. Activating the Command e You can access this command from the image menubar through Image Scale image The Scale Image Dialog GNU Image Manipulation Program Page 252 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Scale Image Image Size Width 200 a Height 210 pixels 200 210 pels X resolution 72 009 resolution 72 009 J pixels in El Quality Interpolation Linear See also the Scale tool which lets you scale a layer a selection or a path Crop Image The Crop Image command crops the image to the boundary of the selection by removing any strips at the edges whose contents are all completely unselected Areas which are partially selected for example by feathering are not cropped If there is no selection for the image the menu entry is insensitive and grayed out This command crops all of the image layers To crop just the active layer use the Crop Layer command Activating the command e You can access this command on the image menu bar through Image Crop Image Autocrop Image The Autocrop Image command removes the borders from an image It searches the active layer for the largest possible border area that is all the same color and then crops this area from the image as if you had used the Crop tool Note carefully that this command only uses the active layer of the image to find borders If other layers
4. Forward traditional 0 Backward corrective Interpolation l Supersampling Clip result Constraints None 0 Keep height lt Ctrl gt Keep width lt Alt gt 0 Keep aspect lt Ctrl gt lt Alt gt The Scaling Information dialog window Shear Tool Shear tool is used to shift one part of an image a layer a selection or a path to a direction and the other part to the opposite direction For instance a horizontal shearing will shift the upper part to the right and the lower part to the left A rectangle becomes a diamond This is not a rotation the image is distorted To use this tool after selecting click on the image or the selection a grid is Surperimposed and the Shearing Information dialog is opened By dragging the mouse pointer on the image you distort the image horizontally or vertically according to the the direction given to the pointer When you are satisfied click on the Shear button in the info dialog to validate Activate Tool e The Shear Tool can be called in the following order from the image menu Tools Transform Tools Shear GNU Image Manipulation Program Page 135 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o e The Tool can also be called by clicking the tool icon e or by using the ShiftS key combination Options Affect fad Transform Direction Forward traditional C Backward correctiv
5. If you publish or distribute Opaque copies of the Document numbering more than 100 you must either include a machine readable Transparent copy along with each Opaque copy or state in or with each Opaque copy a computer network location from which the general network using public has access to download using public standard network protocols a complete Transparent copy of the Document free of added material If you use the latter option you must take reasonably prudent steps when you begin distribution of Opaque copies in quantity to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy directly or through your agents or retailers of that edition to the public It is requested but not required that you contact the authors of the Document well before redistributing any large number of copies to give them a chance to provide you with an updated version of the Document You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above provided that you release the Modified Version under precisely this License with the Modified Version filling the role of the Document thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it In addition you must do these things in the Modified Version A Use in the Title Page and on the covers if any a title d
6. Mode ve EY a Z Antialiasing Feather edges Radius 10 0 Auto shrink selection Sample merged Free select a Width 192 Height 71 px E te al See Selection Tools for help with options that are common to all these tools Only options that are specific to the Rectangle Select tool are explained here Ellipse Selection Tool The Ellipse Selection tool is designed to select circular and elliptical regions from an image with high quality anti aliasing if you want it For information on selections and how they are used in GIMP see Selections for information on features common to all selection tools see Selection Tools This tool is also used for rendering a circle or ellipse on an image To render a filled ellipse create an elliptical selection and then fill it using the Bucket Fill tool To create an elliptical outline the simplest and most flexible approach is to create an elliptical selection and then stroke it However the quality of anti aliasing with this approach is rather crude A higher quality outline can be obtained by creating two elliptical selections with different sizes subtracting the inner one from the outer one however this is not always easy to get right How to Activate he Ellipse Selection Tool can be activated from an image menu as Tools Selection ools Ellipse Select from the Toolbox by clicking on the tool icon or from the keyboard using the shortcut e GNU Im
7. New Color trom BG iy Delete Color Zoom Out Zoom In Q Zoom All The Palette Editor Menu can be accessed by right clicking on the palette display in the Palette Editor or by choosing the top entry from the dialog Tab menu The operations tn it can also be executed using the buttons at the bottom of the Palette Editor dialog Fonts dialog a 2ans Bold g 2ans Bold Italic Aa Sans Italic ey The Fonts dialog is used for selecting fonts for the Text tool It also allows you to refresh the list of available fonts if you add new ones to your system while GIMP is running Activate Dialog The Fonts dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in several ways e From the Toolbox menu File Dialogs Fonts e From the image menu bar Dialogs Fonts e From the Tab menu in any dockable dialog Add Tab Fonts e From the Tool Options for the Text tool If you click on the Font button a Font selector pops up In the lower right corner is a button that if pressed brings up the GNU Image Manipulation Program Page 175 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 9 S o Fonts dialog Using the Fonts dialog The most basic thing you can do is to select a font by clicking on it this font will then be used by the Text tool If instead of clicking and releasing you hold down the left mou
8. Stroke Selection The Stroke Selection command strokes a selection in the image There are two ways you can stroke the selection either by using a paint tool or without using one This means that the selection border which is emphasized in the image with a dotted line can be drawn with a stroke There are various options which you can use to specify how this stroke should look This command is only active if the image has an active selection Activating the Command e You can access this command from the image menubar through Edit Stroke Selection e You can also access it through the Selection Editor The Stroke Selection dialog The options for stroking selections and for stroking paths are the same You can find the documentation about the options in the dialog box in the Stroke Path section Stroke Path The Stroke Path command strokes a path in the image There are two ways you can stroke the path either by using a paint tool or without using one There are various options which you can use to specify how this stroke should look This command is active only if there is a path in your image Activating the Command e You can access this command from the image menubar through Edit Stroke Path e You can also access it by clicking on the button with the same name in the Path dialog Description of the Dialog Window GNU Image Manipulation Program Page 227 of 421 Generated by docbook2odf pe O N E O O 2
9. add layeritheImagelitheLayerll0 PTT TT Now just for fun let s see the fruits of our labors up until this point and add this line to show the new empty image BERRREEE gimp display newlltheImage PTT TT Save your work select Xtns Script Fu Refresh Scripts run the script and a new image Should pop up It will probably contain garbage random colors because we haven t erased it We ll get to that in a second GNU Image Manipulation Program Page 94 of 421 Generated by docbook2odf Gn x e N E O O 2 S O x a 2 x o E hn S 9 Adding The Text Go ahead and remove the line to display the image or comment it out with a as the first character of the line Before we add text to the image we need to set the background and foreground colors so that the text appears in the color the user specified We ll use the gimp context set back foreground functions BERRRREE Gimp context set backgroundll 25582558255 fi BRRRRREE gimp context set foreground inTextColor BERR With the colors properly set let s now clean out the garbage currently in the image by filling the drawable with the background color BERRRREE gimp drawable fillitheLayer BACKGROUND FILL amp PTT TT With the image cleared we re ready to add some text BRRRRBEE set B8theText SERRE car eee cg imp text fontname Ue ec iImage theLayer TTT TTT Oe Ie eee text LTT TTT Oe Oe RU
10. hn o c o GNU Image Manipulation Program Page 307 of 421 Generated by docbook2odf Overview Naito la ia BAe E o lt i ig roar _ AE 2 y a8 id i Image dimensions 300 x 300 Number of unique colors 44201 Uncompressed size 263 KB Filename taj_orig png Compressed size 155 KB Compression ratio approx 2 to 1 This filter is found in Filters Colors Colorcube Analysis It gives data about image dimensions file size color number compression ratio Options v e This filter has no option b Colorify a Overview gt 2 3 0 o GNU Image Manipulation Program Page 308 of 421 Generated by docbook2odf This filter is found in Filters Colors Colorify It renders a greyscaled image like it is seen through colored glass Options Custom Color fo Sa Color to Alpha o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 309 of 421 Generated by docbook2odf X Preview From ji elt to alpha Beep X cancet Pox Overview Lo ke e N xX e e 2 o e ke gt 2 3 0 Ww hn o GNU Image Manipulation Program Page 310 of 421 Generated by docbook2odf This filter is found in Filters Colors Color to Alpha The Color to Alpha filter makes transparent all pixels with a selected color An Alpha channel is created It will attempt to preserve anti a
11. 2 xe o d 3 S o Reporting the Bug Okay so you have done everything you could to make sure and you still think it s probably a bug You should then go ahead and file a bug report To do this begin by going to http bugzilla gnome org enter_bug cgi and go down the page until you can select the component GIMP The first time you file a bug report you will be asked to create a Bugzilla account The process is easy and painless and you probably won t even get any spam as a result This takes you to the bug report form which you should fill out as follows Note that most of the information you enter can be changed later by the developers if you get it wrong so try to get it right but don t be obsessive about it You can ignore the rest When you have filled out all of these things press the Commit button and your bug report will be submitted It will be assigned a number which you may want to make note of you will however be emailed any time somebody makes a comment on your bug report or otherwise alters it so you will receive reminders in any case You can see the current state of your bug report at any time by going to http bugzilla gnome org and at the bottom of the page in the Actions area entering the bug number and pressing the Find button Sometimes it is very helpful to augment a bug report with a screenshot or some other type of data If you need to do this go to the web page for your bug rep
12. After you have rotated an image there will be unpleasant triangular holes at the corners One way to fix them is to create a background that fills the holes with some unobtrusive or neutral color but usually a better solution is to crop the image The greater the rotation the more cropping is required so it is best to get the camera aligned GNU Image Manipulation Program Page 68 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o as well as possible when you take the picture in the first place Cropping When you take a picture with a digital camera you have some control over what gets included in the image but often not as much as you would like the result is images that could benefit from trimming Beyond this it is often possible to enhance the impact of an image by trimming it so that the most important elements are placed at key points A rule of thumb not always to be followed but good to keep in mind is the rule of thirds which says that maximum impact is obtained by placing the center of interest one third of the way across the image both widthwise and heightwise To crop an image activate the Crop tool in the Toolbox or by pressing the C key capitalized while inside the image With the tool active clicking and dragging in the image will sweep out a crop rectangle It will also pop up a dialog that allows you to adjust the dimensions of the crop region if
13. General options Map to Plane Transparent background Tile source image Create new image X Enable antialiasing Preview Qj IQ neh o E ace W Show preview wireframe Threshold 0 250 oa z E Light tab GNU Image Manipulation Program Page 374 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 3 S o i ees T ae Options Light Material Orientation Light Settings Lightsource type Point light T Lightsource color Position X 0 30 kad m Bil GI PE BE 0 30 Preview A Q 7 2 00 Show preview wireframe ea Options Light Material Orientation Intensity Levels Ambient 0 300 oe Diffuse 1 00 Reflectivity Diffuse 0 50 Specular 0 50 i Highlight 27 00 Show preview wireframe Orientation tab Options Light Material Orientation Position 0 67308 10 58654 Fa e Rotation
14. O xe a 2 xe o d 3 S o understood if the Allow window resizing option is unchecked you can see that the content of this rectangle will be enlarged or reduced so that its biggest dimension fit the corresponding dimension of the image window if the biggest dimension of the rectangle is width then it will fit the width of the image window Activate Tool e The Magnify Tool can be called in the following order from the image menu Tools Magnify e The Tool can also be called by clicking the tool icon Key modifiers Defaults Options x Auto resize window Tool Toggle lt Ctri gt Zoom in 0 Zoom out Threshold 1 0 a Zoom menu Using the Magnify tool is not the only way to zoom an image The Zoom menu provides access to several functions for changing the image magnification level For example you can easily choose an exact magnification level from this menu Measure Tool The Measure Tool is used to gain knowledge about pixel distances in your working image By clicking and holding the mouse button you can determine the angle and number of pixels between the point of click and where the mouse pointer is located The information is displayed on the status bar or can also be displayed in the Info Window When you pass the mouse pointer over the end point it turns to a move pointer Then tf you click you can resume the measure GNU Image Manipulation Program Page 149 of 421 Generated
15. One of the most important uses of rulers is to create guides If you click on a ruler and drag into the image display a guideline will be created which you can use to help you position things accurately Guides can be moved by clicking on them and dragging or deleted by dragging them out of the image display QuickMask Toggle At the lower left corner of the image display is a small button that toggles on or off the Quick Mask which Is an alternate and often extremely useful way of viewing the selected area within the image For more details see QuickMask Pointer Coordinates In the lower left corner of the window is a rectangular area used to show the current pointer coordinates that is the mouse location if you are using a mouse whenever the pointer is within the image boundaries The units are the same as for the rulers Units menu This feature is new in GIMP 2 2 it does not appear in GIMP 2 0 By default the units used for the rulers and several other purposes are pixels You can change to inches cm or several other possibilities using this menu If you do note that the setting of Dot for dot in the View menu affects how the display is scaled see Dot for Dot for more information Zoom button This feature is new in GIMP 2 2 it does not appear in GIMP 2 0 There are a number of ways to zoom the image in or out but this menu is perhaps the simplest Status Area The Status Area appears below the image display Most
16. S O xe a 2 xe o d 3 S o Eo W S This tool fills a selection with the current foreground color If you Shift click and use the Bucket tool it will use the background color instead Depending on how the tool options are set the Bucket Fill tool will either fill the entire selection or only parts whose colors are similar to the point you click on The tool options also affect the way transparency is handled The amount of fill depends on what Fill Threshold you have specified The fill threshold determines how far the fill will soread similar to the way in which the magic wand works The fill starts at the point where you click and spreads outward until the color or alpha value becomes too different When you fill objects in a transparent layer such as letters in a text layer with a different color than before you may find that a border of the old color still surrounds the objects This is due to a low fill threshold in the Bucket Fill options dialog With a low threshold the bucket tool won t fill semi transparent pixels and they will stand out against the fill because they have kept their original color If you want to fill areas that are totally transparent you have to choose right click Select Select All and make sure that the layer s Keep Transparency button in the Layers dialog is unchecked If the Keep Transparency button is checked only the opaque parts of the layer will be filled and if yo
17. S O xe a 2 xe o d 3 S o Choose Stroke Style Unnamed 3 2zinnias png Stroke line Line Width 6 0 7 Line Style Cap style Join style Miter limit aa 10 0 o Dash pattern lt oom Dash preset Custom hal x Antialiasing Solid C Pattern 0 Stroke with a paint tool The Choose Stroke Style dialog box allows you to choose between stroking the path with the options you specify or stroking it with a paint tool If you stroke the path with a paint tool the current paint tool options are used to draw the stroke pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 228 of 421 Generated by docbook2odf Select Introduction to the Select menu ers Ctrl Jone Shitt Ctrl A ad invert Ctr 9 Float Shift Ctrl L TA By Color Shift O From Path Shift E Selection Editor x Feather Sharpen a Shrink a 24 Grow Border Toggle QuickMask Shit Q Save to Channel Bb To Path This section explains the commands on the Select menu of the image menubar Besides the commands presented here you might also find other entries on the menu They are not part of GIMP itself but are extensions plug ins You can find descriptions of these menu entries with the documentation of the plug ins Select All The Select All command creates a new selection which contains everything on the current
18. The GIMP developers have made a great effort to keep the XCF file format compatible across versions If you create a file using GIMP 2 0 it ought to be possible to open the file in GIMP 1 2 However some of the information in the file may not be usable for example GIMP 2 0 has a much more sophisticated way of handling text than GIMP 1 2 so a text layer from a GIMP 2 0 XCF file will appear as an ordinary image layer if the file is opened in GIMP 1 2 GNU Image Manipulation Program Page 407 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o hn S o The YCbCr color model was developed for the PAL television standard as a color model that is an easy deviation from the YUV color model In the meantime it has become the CCIR 601 standard for image and video recording For example it is used for JPEG pictures and MPEG videos and therefore also on DVDs video CDs and for most other widespread digital video standards Note that a color model is still not a color space since it doesn t determine which colors are actually meant by red green and blue For a color space there still needs to be a reference to a specific absolute color value There are color models which do not express a color by the additive basic colors red green and blue RGB but by other properties for example the brightness color model Here the criteria are the basic brightness of the colors from black throug
19. This filter is found in the image window menu under Filters Map Warp This filter has no Preview This filter displaces pixels of active layer or selection according to grey levels of a Displacement map Pixels are displaced according to the gradient slope in the displacement map Pixels corresponding to solid areas are not displaced the higher the Slope the higher the displacement This filter offers the possibility of masking a part of the image to protect it against filter action Options pe O N E O O 2 S O xe a 2 xe o G 3 S o GNU Image Manipulation Program Page 379 of 421 Generated by docbook2odf Basic Options step size Displacement map Iterations Warpa2 png 7 Background 14 On edges Wrap Smear Black FG color Advanced Options Dither size 0 00 Magnitude map Rotation angle 90 0 B E werpb2 png a packground 16 Substeps 1 A Use magnitude map More Advanced Options Gradient scale 0 000 o warpa2 png 7 Background 14 Vector mag 0 000 S warpa2 png 7 Background 14 Angle 0 0 a Van Gogh LIC Overview This filter is found in the image window menu under Filters Map Van Gogh LIC LIC stands for Line Integral Convolution a mathematical method Plug in author uses mathematical terms to name his options This filter is used to apply a directional blur to an image or to create textures It could be called Astigmatism as it blurs certai
20. di Duplicate Palette Merge Palettes i Delete Palette Cy Refresh Palettes The Palettes Menu can be accessed by right clicking in the Palettes dialog or by choosing the top item from the dialog Tab menu Palette Editor Palette Editor a a Plasma copy united Comns fis _ The Palette Editor is used mainly for two purposes first for setting GIMP s foreground or background colors as shown in the Color Area of the Toolbox to selected colors from the palette second for modifying the palette You can activate the Palette Editor for any palette in the Palettes dialog but you can only modify palettes that you have created yourself not the palettes that are supplied when you install GIMP You can however duplicate any palette and then edit the newly created copy If you modify a palette the results of your work will automatically be saved when you exit from GIMP How to Activate the Palette Editor The Palette Editor is only accessible from the Palettes dialog you can activate it by double clicking on a palette or by pressing the Edit Palette button at the bottom or by choosing Edit Palette from the Palettes Menu The Palette Editor is a dockable dialog see the section on Dialogs and Docking for help on Manipulating it Using the Palette Editor If you click on a color box tn the palette display GIMP s foreground color will be set to the selected color you
21. 2 S O xe a 2 xe o d 3 S o checked Let s Suppose that your image has more than one layer a selection and a guide The mouse pointer takes the shape of the familiar 4 way arrow when it passes over the image elements originating from the active layer then click and drag will move the active layer When the mouse pointer is on an image element originating from a non active layer or on a guide it looks like a small hand then click and drag will move this layer or this guide To move a selection frame without moving its content Use the CtrlAlt key combination This has the same action as selecting Selection in Affect Key modifiers Defaults Options Tool Toggle lt Shift gt Pick a layer or guide 0 Move the current layer The Crop Tool is used to crop or clip an image or layer This tool is often used to remove borders or to eliminate unwanted areas to provide you with a more focused working area It is also useful If you need a specific image size that does not match the original dimensions of your image To use the tool click inside the image and drag out a rectangular region before releasing the mouse button When you click a dialog pops up showing you the dimensions of the crop region and allowing you to perform various actions If you want to alter the crop region you can do so either by clicking and dragging on the corners or by changing the values in the dialog When you are ready y
22. Add Alpha Channel Color to Alpha Semi Flatten Threshold Alpha H Alpha to Selection GF Add to Selection The Transparency submenu contains commands which use or affect the alpha channel of the active layer Activating the Submenu e You can access this submenu from the image menubar through Layer Transparency The Contents of the Transparency Submenu The Transparency submenu contains the following commands Add Alpha Channel The Add Alpha Channel command adds an alpha channel to the active layer Without an alpha channel a layer cannot have transparency or a layer mask If the active layer already has an alpha channel and it must unless it is the bottom layer of the image the menu entry is insensitive and grayed out Activating the Command e You can access this command from the image menubar through Layer Transparency Add alpha Channel Color to Alpha You can make colors of the active layer transparent by using the Color to Alpha command You can find a description of this command in the section about the filter This command operates only on the layer which is active at the time the command is called Even after you choose another layer to be the active layer the operation continues to affect the layer on which you performed the command Activating the Command GNU Image Manipulation Program Page 273 of 421 Generated by docbook2odf xe O N E O O 2 S O xe a 2 xe o d 3 S
23. Close Tab button highlighted in the figure to the right will close the frontmost dialog GNU Image Manipulation Program Page 60 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o How to Set Your Tile Cache A low value for tile cache means that Gimp sends data to the disk very quickly not making real use of the available RAM and making the disks work for no real reason Too high a value for tile cache and other applications start to have less system resources forcing them to use swap space which also makes the disks work too hard some of them may even terminate or start to malfunction due lack of RAM How do you choose a number for the Tile Cache size Here are some tips to help you decide what value to use as well as a few tricks e The easiest method is to just forget about this and hope the default works This was a usable method when computers had little RAM and most people just tried to make small images with GIMP while running one or two other applications at the same time If you want something easy and only use GIMP to make screenshots and logos this is probably the best solution e If you have a modern computer with plenty of memory say 512 MB or more setting the Tile Cache to half of your RAM will probably give good performance for GIMP tn most situations without depriving other applications Probably even 3 4 of your RAM would be fine e Ask someone
24. G d 3 S o GNU Image Manipulation Program Page 411 of 421 Generated by docbook2odf The One to change the world pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 412 of 421 Generated by docbook2odf New in GIMP 2 Sad to say no version of GIMP has yet been absolutely perfect Even sadder it is likely that no version ever will be In spite of all efforts to make everything work a program as complicated as GIMP is bound to screw things up occasionally or even crash But the fact that bugs are unavoidable does not mean that they should be passively accepted If you find a bug in GIMP the developers would like to Know about it so they can at least try to fix It Suppose then that you have found a bug or at least think you have you try to do something and the results are not what you expect What should you do How should you report it The procedure for making an enhancement request that is for asking the developers to add a missing feature is nearly the same as the procedure for reporting a bug The only thing you do differently is to mark the report as an enhancement at the appropriate stage as described below In common with many other free software projects GIMP uses a bug reporting mechanism called Bugzilla This is a very powerful web based system capable of managing thousands of bug reports without losing track In fact GIMP shares its Bugz
25. Make Brush Misc Patterns Utils Web Page Themes Refresh Scripts Script Fu Console Start Server The Script Fu command displays a submenu which contains a large number of Script Fu scripts and options including the Script Fu console Script Fu is a language for writing scripts which allow you to run a series of GIMP commands automatically Activating the submenu e You can access this command from the toolbox menubar through Xtns Script Fu GNU Image Manipulation Program Page 212 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o The Help Menu of the Toolbox Window Introduction to the Help menu j Help F1 Context Help Shift F1 y Lip of the Day aw About The GIMP Online The Help menu contains commands that assist you while you are working with The GIMP You may find other commands besides the ones described here on your computer These commands are not part of The GIMP itself but have been added by some of the plug ins Please refer to the documentation on the extensions for more information about these menu commands Help The Help command displays the GIMP Users Manual in a browser You can set the browser you would like to use in the Help System section of the Preferences dialog as described in The broswer may be the built in GIMP help browser or it may be a web browser If the help does not seem to work please verify that the Gimp Users Man
26. Medium a Get Monitor Resolution From windowing system currently 101 x 101 dpi Manually Horizontal Vertical 101 000 E 101 000 E dpi Calibrate Options Measure the ruters and enter them lengths below Horizontal BREE 3 l Yertical 5 556 inches Input Devices o a a o N x e o 2 8 o 3 gt 2 x o ww hn o c o GNU Image Manipulation Program Page 194 of 421 Generated by docbook2odf Input Devices Extended Input Devices 2 Configure Extended Input Devices Save input device settings on exit Leal Save Input Device Settings Now w Reset Saved Input Device Settings to Default Values Input Controllers GNU Image Manipulation Program Generated by docbook2odf Page 195 of 421 pe O N E O O 2 S O xe a 2 xe o d 3 S o Input Devices Extended Input Devices Contigure Extended Input Devices Save input device settings on exit Save Input Device Settings Now Reset Saved Input Device Settings to Default Values This dialog has two tabs that allow you to assign actions to the mouse wheel and to keyboard keys Main Mouse Wheel tab You will find an example of these notions in Creating a variable size brush Window Managment pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 196 of 421 Generated by docb
27. N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 31 of 421 Generated by docbook2odf GIMP paths belong to a mathematical type called Bezier paths What this means in practical terms is that they are defined by anchors and handles Anchors are points the path goes through Handles define the direction of a path when it enters or leaves an anchor point each anchor point has two handles attached to it Paths can be very complex If you create them by hand using the Path tool unless you are obsessive they probably won t contain more than a few dozen anchor points often many fewer but if you create them by transforming a selection into a path or by transforming text into a path the result can easily contain hundreds of anchor points or even thousands A path may contain multiple components A component is a part of a path whose anchor points are all connected to each other by path segments The ability to have multiple components in paths allows you to convert them into selections having multiple disconnected parts Each component of a path can be either open or closed closed means that the last anchor point is connected to the first anchor point If you transform a path into a selection any open components are automatically converted into closed components by connecting the last anchor point to the first anchor point with a straight line Path segments can be either straight
28. O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 187 of 421 Generated by docbook2odf Help System General W Show tool tips Show help buttons Show tips on startup Help Browser Help browserto use GIMP help browser hd Web Browser Web browser to use firefox 5 Pe a Cancel Options Tool Options pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 188 of 421 Generated by docbook2odf Options Toolbox Tool Options Guide and Grid Snapping Snap distance E Finding Contiguous Regions Default threshold 15 Scaling Default interpolation Linear Paint Options Shared Between Tools F Brush S Y Pattern J Gradient GNU Image Manipulation Program Generated by docbook2odf Page 189 of 421 pe O N E O O 2 S O xe a 2 xe o d 3 S o Toolbox Appearance a M Show foreground amp background color j f Show active brush pattern amp gradient ae M Show active image Options Ale Xtns Help This page lets you customize the appearance of the Toolbox by deciding whether the three context information areas should be shown at the bottom Image Windows o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o GNU Image Manipulation Program Page 190 of 421 G
29. The Size map editor is an annexe of the GIMPressionist filter You can get to it by clicking on the Edit button in the Size tab With this editor you can set the size that brush strokes given by filter will have Parameter Settings Smvectors Size Strength Strength exp Preview Voronol You can place one or several vectors You can set their strength They will act on the corresponding area of the image Oilify GNU Image Manipulation Program Generated by docbook2odf Page 365 of 421 pe O N E O O 2 S O xe a 2 xe o d 3 S o Parameter Settings Overview a i ri m i aii Te a z Sf r r This filter is found in Filters Artistic Oilify This filter makes the image look like an oil painting The Mask Size controls the outcome a high value gives the image less detail as if you had used a larger brush The Gimpressionist filter can produce similar effects but allows a much wider variety of options o al 3 o N x e o 2 8 o 3 gt 2 v o ww hn o c o GNU Image Manipulation Program Page 366 of 421 Generated by docbook2odf Options X Preview Mask size 2 7 S Use intensity algorithm Photocopy Overview Lo ke e N xX e e 2 o e ke gt 2 3 0 Ww hn o GNU Image Manipulation Program Page 367 of 421 Generated by docbook2odf The Photocopy filter modifies the act
30. This prevents you from moving the layer up in Ro A the Layers dialog and selecting Add Alpha Channel xX Show tip next time GIMP starts K Previous tip Next tip gt M Close A new tip is displayed each time you start The GIMP You can disable this by un checking the Show tip next time GIMP starts box on the dialog About The About command shows the About window which displays information about the version of The GIMP you are running and the many authors who wrote it Activating the About Command e You can access this command in the toolbox menu through Help About Description of the dialog window The GIMP Online Developer Web Site Main Web Site Plug in Registry The GIMP online command displays a submenu which lists several helpful web sites that have to do with various aspects of GIMP You can click on one of the menu items and your web browser will try to connect to the URL o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 214 of 421 Generated by docbook2odf The File Menu of the Image Window File menu New IF Open a Open Location Open Recent b al Save CtrhS Save as Shift Ctrl S save a Copy Save as Template i Revert Mail Image X Close Wea Quit Print New gt Open Q Open Location Open Recent Acquire Preferences Dialogs i Quit ctrl Q There is a File menu
31. When your mask is painted you can transform it to a selection by clicking on the Channel to selection button or from the context menu You can work in selection masks not only with the paint tool but also with other tools For instance you can use the selection tools to fill areas uniformly with gradients or patterns By adding many selection masks in your list you can easily compose very complex selections One can say that a selection mask is to a selection as a layer is to an image As long as a Selection mask is activated you are working in the mask and not in the image To work in the image you have to deactivate all selection masks Don t forget also to stop displaying masks in the image by removing the eye icon Check also that all RGB and Alpha channels are activated and displayed in the image Quick Mask A Quick Mask is a Selection Mask intended to be used temporarily to paint a selection Temporarily means that unlike a normal selection mask it will not be saved in the list after its transformation to selection The selection tools sometimes show their limits when they have to be used for doing complex drawing selection as progressive In this case using the QuickMask Is a good idea which can give very good results Activate Tool e The QuickMask can be activated in the following order from the image menu Select Toggle QuickMask e The QuickMask can also be activated by clicking the left bottom button showed in red on th
32. You can save all this log or only a selected part Activate Dialog e You will find this command in the toolbox menu bar through File Dialogs Error Console The Error Console Dialog GNU Image Manipulation Program Page 201 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Error Console Fe help Message The GIMP help files are not installed Could not open usr share gimp 2 0 help en gimp help xml for reading No such file or directory Please check your installation e Clear errors This button lets you delete all errors in the log e Save all errors This button lets you save the whole log You can also select a part of the log by click and dragging the mouse pointer or by using the ShiftArrow keys key combination and save only this selected part by pressing the Shift key A dialog window Save Error Log to File lets you choose the name and the destination directory of this file Name Save in folder FQHome t Browse for other folders You will as well find these button actions in the dialog sub menu by clicking on GNU Image Manipulation Program Page 202 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 3 S o Chapter Menus pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 203 of 421 Generated by do
33. active layer or selection into several pieces with square form and then slides them so that they more or less overlap or move apart They can go out image borders a little Options Division Movement Max 25 Wrap around Background Type Fractional Pixels O Transparent Background Inverted image C Ignore Force Foreground color 0 Background color X Centering 0 Select here Small Tiles Overview This filter is found in the image window menu under Filters Map Small Tiles This filter reduces the image active layer or selection and displays it in many copies inside the original image Options o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o GNU Image Manipulation Program Page 377 of 421 Generated by docbook2odf Flip Horizontal Vertical Reset All tiles O Alternate tiles Explicit tile 0 pacity Number of Segments Ly 2 n ie Tile Overview This filter is found in the image window menu under Filters Map Tile This filter makes several copies of the original image in a same or reduced size into a bigger new image Tile to New Size Width E Height 138 x Create New Image o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o GNU Image Manipulation Program Page 378 of 421 Generated by docbook2odf Warp Overview
34. and that will create some noise in the image GNU Image Manipulation Program Page 336 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o G d 3 S o In this image the studied pixel has a red border and the studied matrix has a green border hope you have understood how to go on with the process and get a 3x3 pixel block when the I pixel is inside the green border the studied pixel turns to black A larger dark area will dilate by one pixel in all directions 0 2 0 The filter was applied 3 times On more complex images dark areas are widenned and enhanced the same and somewhat pixellated Here the filter was applied 3 times Of course if background is darker than foreground it will cover the whole image Options This filter has no options Examples Erode Overview This filter is found in Filters Generic Erode This filter widens and enhances bright areas of the active layer or selection For every image pixel it brings the pixel Value luminosity into line with the upper Value pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 337 of 421 Generated by docbook2odf the brightest of the 8 neighbouring pixels 3x3 matrix So a bright pixel is added around bright areas An isolated pixel on a darker background will be changed to a big pixel composed of 9 pixels and that will create
35. and you have problems about lack of resources then you should decrease the amount of RAM available to GIMP Another trick is to put the Swap Dir on a very fast disk or on a different disk than the one where most of your files reside Spreading the operating system swap file over multiple disks is also a good way to speed things up in general And of course you might have to buy more RAM or stop using lots of programs at the same time you can not expect to edit a poster on a computer with 16MB and be fast You can also check what memory requirements your images have The larger the images and the number of undos the more resources you need This is another way to choose a number but it is only good if you always work with the same kind of images and thus the real requirements do not vary It is also helpful to know if you will require more RAM and or disk space GNU Image Manipulation Program Page 62 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Chapter Using GIMP as an Intermediate GNU Image Manipulation Program Page 63 of 421 Genera ted by docbook2odf Using the Quickmask Open an image or begin a new document Activate the Quickmask using the left bottom button in the image window If a selection is present the mask Is initialized with the content of the selection Choose any drawing tool Paint on the Quick Mask using black color to remove selected ar
36. as List In Grid mode templates are laid out in a rectangular array of identical icons unless you gave them a particular icon as we will see later Only the name of the selected template is displayed In List mode they are lined up vertically icons are identical too all names are displayed In this Tab menu the Preview Size option allows you to change the size of thumbnails Using the Templates dialog You select a template by clicking on its icon Right clicking reveals a local menu that offers the same functions as buttons The buttons at the bottom of the dialog allow you to operate on templates in several ways GNU Image Manipulation Program Page 180 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o Edit Template Edit Template J Width 540 Height 480 pixels 2 34 MB b Advanced Options The dialog allows you to set the specifications of the selected template You can access to this editor by clicking on the Edit Template button in the Templates dialog The Advanced Options dialog These are options that will mainly be of interest to more advanced users o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o GNU Image Manipulation Program Page 181 of 421 Generated by docbook2odf Misc dialogs Tools dialog iF Ink EA Clone Convolve EJ Smudge Dodge Burn Color Balance z4 Hue Satura
37. beyond which GIMP will begin to delete the oldest items from the Undo History Even though the Undo History is a component of an image it is not saved when you save the image using GIMP s native XCF format which preserves every other image property When the image Is reopened it will have an empty Undo History The implementation of Undo by GIMP is rather sophisticated Many operations require very little Undo memory e g changing visibility of a layer so you can perform long sequences of them before they drop out of the Undo History Some operations changing layer visibility is again an example are compressed so that doing them several times in a row produces only a single point in the Undo History However there are other operations that may consume a lot of undo memory Most filters are examples of this because they are implemented by plug ins the GIMP core has no really efficient way of Knowing what they have changed so it has no way to implement Undo except by memorizing the entire contents of the affected layer before and after the operation You might only be able to perform a few such operations before they drop out of the Undo History Things that cannot be Undone Most actions that alter an image can be undone Actions that do not alter the image generally cannot be This includes operations such as saving the image to a file duplicating the image copying part of the image to the clipboard etc It also includes most acti
38. can be set to act specifically on paths using the Affect option in the tool s Tool Options dialog This gives you a powerful set of methods for altering the shapes of paths without affecting other elements of the image By default a Transform tool when it is set to affect paths only acts on a single path the active path for the image which is shown highlighted in the Paths dialog You can make a transformation affect more than one path and possibly other things as well using the transform lock buttons in the Paths dialog Not only paths but also layers and channels can be transform locked If you transform one element that is transform locked all others will be transformed in the same way So for example if you want to scale a layer and a path by the same amount click the transform lock buttons so that chain symbols appear next to the layer in the Layers dialog and the path in the Paths dialog then use the Scale tool on either the layer or the path and the other will automatically follow GNU Image Manipulation Program Page 67 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 3 S o Working with Digital Camera Photos Introduction One of the most common uses of the GIMP is to fix digital camera images that for some reason are less than perfect Maybe the image is overexposed or underexposed maybe rotated a bit maybe out of focus these are all common problems fo
39. e e 2 8 e D gt 2 D 0 Ww hn 0 0 LU GNU Image Manipulation Program Page 361 of 421 Generated by docbook2odf This filter is found tn Filters Artistic Cartoon The Cartoon filter modifies the active layer or selection so that it looks like a cartoon drawing Its result is similar to a black felt pen drawing subsequently shaded with color This is achieved by darkening areas that are already distinctly darker than their neighborhood Options X Preview Mask radius 7 00 5 Percent black m 0 200 S Cubism Parameter Settings Use Background Color POPUP eee Ca Tile size P J J10 0 5 Tile Saturation _ J 2 5 B a Cancel Overview GNU Image Manipulation Program Page 362 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o This filter is found tn Filters Artitic Cubism The Cubism plug in modifies the image so that it appears to be constructed of small Squares of semitransparent tissue paper If setting possibilities of this filter are not enough for you see GIMPressionist filter which offers more options Options Pa el X Preview Tile size Use background color If you are using this to generate background images for web pages and the like work with a small range of colors painted randomly on a small square Then apply the Cubism filter with the desired settings As a last step try Fi
40. e You can access this submenu from the image menubar through Image Guides The Contents of the Guides Submenu The Guides submenu contains the following commands e New Guide e New Guide by Percent e New Guides from Selection e Remove all Guides Remove all guides The Remove all Guides command removes all guides from the image Activating the Command e You can access this command from the image menubar through Image Guides Remove all guides New Guide by Percent The New Guide by Percent command adds a guide to the image The position of the guide Is specified as a percentage of the Height and Width You can add guides to the image more quickly by simply clicking and dragging guides from the image rulers and positioning them where you would like Guides you draw with click and drag are not as precisely positioned as those you draw with this command however Activating the Command e You can access this command from the image menubar through Image Guides New Guide by Percent New Guide by Percent Options Script Arguments Direction Horizontal T Position 0 a Script Progress none pre oo New Guide The New Guide command adds a guide to the image For more information about guides see the glossary entry on Guides You can add guides to the image more quickly but less accurately by simply clicking and GNU Image Manipulation Program Page 256 of 421 Generated by docbook2odf pe O
41. etc GIMP is expandable and extensible It is designed to be augmented with plug ins and extensions to do just about anything The advanced scripting interface allows everything from the simplest task to the most complex image manipulation procedures to be easily scripted One of The GIMP s strengths is its free availability from many sources for many operating systems Most GNU Linux distributions include The GIMP as a standard application The GIMP is also available for other operating systems such as Microsoft Windows or Apple s Mac OS X Darwin The GIMP is not freeware It is a Free Software application covered by the General Public License GPL license The GPL provides users with the freedom to access and alter the source code that makes up computer programs Authors The first version of the GIMP was written by Peter Mattis and Spencer Kimball Many other developers have contributed more recently and thousands have provided support and testing GIMP releases are currently being orchestrated by Sven Neumann and Mitch Natterer and many other people called the GIMP Team The GIMP Help system The GIMP Help system provides you with the information necessary to understand how to use The GIMP You can get context sensitive help while using GIMP by pressing the F1 key Help on specific menu items can be accessed by pressing the F1 key while the mouse focuses the menu item Read on to begin your GIMP journey Features and Capabilities
42. floating selections were used for performing operations on a limited part of an image You can do that more easily now with layers but you can still use this way of working with images In addition to using the Float command you can also create a floating selection by moving a selection using the Move tool without pressing the Alt key or ShiftAlt in Linux which automatically creates a floating selection You can also create a temporary layer named Floating Selection with the entries on the Layer menu You cannot perform any operations on other layers if the image has a floating selection so after you make the changes you want to the floating selection you have to anchor tt That is you have to attach it to a normal non floating layer usually the original layer the one which was active previously To anchor the floating selection use the Anchor Layer command You can also anchor it to an existing layer by clicking anywhere on the image outside of the floating selection which then merges it with the background layer You can also anchor it to a new layer by using the New Layer command If you display the layer boundary by using the Show Layer Boundary command you may have difficulty selecting a precise area of the image which you want in a layer To avoid this problem you can make a rectangular selection transform it into a floating selection and anchor it to a new layer Then simply remove the original layer Activating the Co
43. layer Activating the Command e You can access this command from the image menubar through Select All e or by using the keyboard shortcut Ctrl A You can also access it with the Selection Editor None The None command cancels all selections in the image If there are no selections the command doesn t do anything Floating selections are not affected Activating the Command e You can access this command from the image menubar through Select None In addition you can use the Selection Editor to access It e You can also use the keyboard shortcut Shift Ctrl A Invert GNU Image Manipulation Program Page 229 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o The Invert command inverts the selection in the current image That means that all of the image contents which were previously outside of the selection are now inside it and vice versa If there was no selection before the command selects the entire image Don t mix up this command with the Invert layer command Activating the Command e You can access this command from the image menubar through Select Invert In addition you can use the Selection Editor to access it e You can also use the keyboard shortcut Ctrl Float The Float command converts a normal selection into a floating selection You can find more information about floating selections in the Glossary In early versions of GIMP
44. mi em F E i NEA LELES Faan Ti n a z s i Bia a TTL ay 3 Fe F ia pir ge eee o M 7 7 IEL You can find this filter via the image menu under Filters Glass effects Glass Tile After applying this filter the active layer or selection is rendered as through a glass brick 5 e wall x 7 e Options 2 0 e xe P 2 xe Q Q S 0 Oo GNU Image Manipulation Program Page 341 of 421 Generated by docbook2odf X Preview Tile width h0 e ji Tile height _ k 20 D Light Effects filters Light Effects filters introduction Light Effects filters render several illumination effects of the image FlareFX Center of FlareFX Me 28 Y 128 l Show Cursor Overview This filter is found in Filters Light Effectsender FlareFX This filter gives the impression that sun hit the objective when taking a shot You can locate the reflection with a reticule you can move but you have not the possibilities that Gflare filter offers Options Gflare GNU Image Manipulation Program Page 342 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o Parameters Radius __t_J 277 0 Rotation st J 65 5 Hue Rotation _ J 0 0 Vector Angle J 60 0 Vector Length tJ 4591 3 f Adaptive Supersampling Max Depth t J 3 B f Auto Update Preview Cancel Overview This filter is
45. moving the brush repeatedly over an area will increase the effect with each additional pass The Rate control allows you to determine how quickly the modifications accumulate The Opacity control however can be used to limit the amount of blurring that can be produced by a single brushstroke regardless of how many passes are made with it How to Activate he Convolve tool can be activated from an image menu as Tools Paint Tools _IConvolve from the Toolbox by clicking on the tool icon or from the keyboard using the shortcut V Key modifiers See the Brush Tools Overview for a description of key modifiers that have the same effect on all brush tools e Ctrl Holding down the Ctrl key toggles between Blur and Sharpen modes it reverses the setting shown in the Tool Options Tool Options GNU Image Manipulation Program Page 127 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Convolve Opacity M 1000 J Mode Normal z Brush Pressure Sen sitivity E Hardness Hl Rate C Size Fade out Length E px Hard edge Convolve Type lt Ctrb gt Blur Sharpen See the Brush Tools Overview for a TIE of tool options that apply to many or all brush tools Dodge or Burn The Dodge or Burn tool uses the current brush to lighten or darken the colors in your image The mode will determine which type of pixels are affected Activate Tool
46. perfect we will enhance the result with the selection mask we are going to create Make sure you have selected the right layer when you call the Threshold tool when it is opened you can t change to another layer pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 142 of 421 Generated by docbook2odf Make sure the image displaying the selected layer is active and copy it to the clipboard with CtrlC Now make the original image active Click on the Quick Mask button at the bottom left corner of the image window the image gets covered with a red default translucent mask This red color does not suit well to our image with much red go to the Channel Dialog activate the Quick mask channel and change this color with the Edit Channel Attributs Come back to the original image Press CtrlV to paste the previously copied layer Voila Your selection mask is ready you can improve the selection as usually When the selection is ready disable the Quick mask by clicking again on its button you will see the marching ants around the selection xe e N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 143 of 421 Generated by docbook2odf We used the Zoom to work at a pixel level the Lasso to remove large unwanted areas the pencil to get hard limits black paint to remove selected areas white paint to ad
47. thanks to Its Animate option to create the elements of a fade in fade out animation between the original image and the deformed one that you can play and use in a Web page To use it first select a deform type then click on the Preview and drag the mouse pointer Settings Example Mosaic pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 350 of 421 Generated by docbook2odf Parameter Settings Tile size P__ Ds 15 0 Color Averagin B a a Tile Height _ 4 0 l W Allow Tile splitting Tile Spacing Pitted Surfaces EG 8G Lighting Tile Neatness Tiling Primitives Light Direction Squares Color Variation Hexagons Octagons amp Squares Cancel Overview This filter is found in Image gt Filters Distorts Mosaic It cuts the active layer or selection into many squares or polygons which are slightly raised and separated by joins giving so an aspect of mosaic Options Page Curl Curl Location Upper Left C Upper Right Lower Left Curl Orientation Horizontal Vertical w Shade under Curl r Use Current Gradient instead of FG BG Color Curl Opacity 100 ee lI Overview This filter is found in Image gt Filters Distorts Pagecurl It curls a corner of the current layer or selection into a kind of cornet showing the underlying layer in the cleared area A new Curl Layer and a new Alpha channel are created T
48. 2 S O xe a 2 xe o d 3 S o selections The feather radius which you can adjust determines the distance over which the transition occurs If you are following along try this out with the Rectangle Select tool and then toggle QuickMask You will now see that the clear rectangle has a fuzzy edge Feathering is particularly useful when you are cutting and pasting in helping the pasted object to blend smoothly and unobtrusively with its surroundings Actually it is possible to feather a selection at any time even if it was originally created as a Sharp selection You can do this from the image menu by choosing Select Feather This brings up a dialog that allows you to set the feather radius You can do the opposite Sharpen a graduated selection into an all or nothing selection by choosing Select Sharpen For technically oriented readers feathering works by applying a Gaussian blur to the selection channel with the specified blurring radius Making a selection partially transparent You can set layer opacity but you cannot do that directly for a selection It is quite useful to make the image of a glass transparent You can achieve this by using these methods e For simple selections use the Eraser tool with the wanted opacity e For complex selections use the command Selection Floating to create a floating selection This creates a new layer called Floating Selection Activate it and use the opacit
49. 2 xe o d 3 S o would like to save or you can cancel the command Note that if you have a large number of images open or are using a large part of the RAM on your system it may take a little while for everything to shut down Activating the Command e You can access this command from the Toolbox menubar or the image menubar through File Quit e or by using the keyboard shortcut Ctrl Q e For most systems on which the GIMP runs you can also execute it by clicking ona Close button somewhere on the Toolbox window s titlebar The location and appearance of this button are determined by the windowing system and the window manager If you close the image window as described above GIMP simply closes your image However if you close the Toolbox window by using the C ose button GIMP itself exits pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 221 of 421 Generated by docbook2odf The Edit Menu of the Image Window Edit menu entries Undo Semi Flatten CtrhZ Redo Ctri Y S Undo History Jo Cut Copy Copy Visible Paste H Paste Into Fig Paste as New Butter te Clear I Fil with EG Color Fill with BG Color Fill with Pattern IE Stroke Selection if Stroke Path In this section you will find help for commands in the Edit menu item You may find commands in the menu which are not described here They don t belong to
50. Aoo o Parameter Settings Radius LI 3 Black Level L J 7 l White Level F __ 248 Cancel Overview This filter is found in Image gt Filters Enhance Despeckle It is used to remove small defects due to dust or scratches on a scanned image and also moir effect on image scanned from a magazine You ought to select isolated defects before applying filter Options Destripe Overview This filter is found in Image gt Filters Enhance Destripe It is used to remove vertical stripes caused by poor quality scanners It works by adding a pattern that will interfere with the image removing stripes if setting is good This negative pattern is calculated from vertical elements of the image so don t be surprised if you see stripes on the preview of an image that has none And if pattern strength is too high you image will be striped If after a first pass a stripe persists rectangular select it and apply filter again all other GNU Image Manipulation Program Page 329 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o selection type may worsen the result Options NL Filter Filter Alpha Trimmed Mean C Optimal Estimation Edge Enhancement Parameter Settings Alpha Ei ___ Es 0 30 Radius Ey 0 30 a Cancel Overview This filter is found in Filters Enhance NL Filter NL means Non Linear Derived from the Unix pnmnlfilt prog
51. Check Color 8 Select Custom Color 7 As in Preferences You can change the color of the canvas which surrounds the image by using the Padding Color command The canvas is the surface the image lies on It looks like a frame around the image in the image window This is just a matter of personal preference since the padding color does not have any effect on the image itself Please note that this color is not the same as the color used by the Fill tool GNU Image Manipulation Program Page 243 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Activating the submenu e You can access this command from the image menubar through View Padding Color Padding Color Options e From Theme The color of the theme defined in Preferences Theme is used e Light Dark Check Color The check representing transparency which is defined in Preferences Display is used e Select Custom Color Opens the Color Selector window to let you choose a color to use e As in Preferences The color selected in the Image Window Appearance Is used Show Menubar The Show Menubar command enables and disables displaying the menubar It may be useful to disable it if you are working in full screen mode If the menubar is not displayed you can right click on the image to access the menubar entries You can set the default for the menubar in the Image Window Appearance dialog Activating the
52. E prega ey E o This filter is found in the image menu via Filters Colors Smooth Palette It creates a striped palette from colors in active layer or selection The main purpose of this filter is to create color maps to be used with the Flame filter Options Value invert Overview MULT Lo ke e N xX e e 2 o e ke gt 2 3 0 Ww hn o GNU Image Manipulation Program Page 319 of 421 Generated by docbook2odf This filter is found in Filters Colors Value Invert This filter inverts Value luminosity of the active layer or selection Hue and Saturation will not be affected although the color will sometimes be slightly different because of round off error If you want to invert Hue and Saturation also use Layers Colors Invert Note that hue and saturation can be distorted quite a bit by this filter for colors with a high luminosity for instance HSV 102 100 98 a bright green gives HSV 96 100 2 Thus you should not expect to be able to apply this filter twice in a row and get back the image you started with Options This filter has no options o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o GNU Image Manipulation Program Page 320 of 421 Generated by docbook2odf Noise filters Noise filters introduction Noise filters add noise to the image To remove small defects from an image see Despeckle filter Hurl Parameter Set
53. GIMP fonts folder which you should not alter even though it is actually empty and a fonts folder inside your personal GIMP directory You can add new folders to the font search path if it is more convenient for you FreeType 2 is a very powerful and flexible system By default it supports the following font file formats e TrueType fonts and collections e Type 1 fonts e ClD keyed Type 1 fonts e CFF fonts e OpenType fonts both TrueType and CFF variants GNU Image Manipulation Program Page 79 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o e SFNT based bitmap fonts e X11 PCF fonts e Windows FNT fonts e BDF fonts including anti aliased ones e PFR fonts e Type42 fonts limited support You can also add modules to support other types of font files See FREETYPE 2 for more information Linux On a Linux system if the Fontconfig utility is set up as usual all you need to do to add a new font is to place the file in the directory fonts This will make the font available not only to GIMP but to any other program that uses Fontconfig If for some reason you want the font to be available to GIMP only you can place it in the fonts subdirectory of your personal GIMP directory or some other location in your font search path Doing either will cause the font to show up the next time you start GIMP If you want to use it in an already running GIMP press the
54. GIMP itself but have been added by some of the plug ins You can find a description of these menu commands in the documentation for the corresponding plug ins Undo If you have made drawing or editing changes to the image which you don t want to keep the Undo command allows you to undo the last change and return the image to its previous state Almost anything you do to an image can be undone in this way with the exception of scripts which deactivate this function Further Undo operations may be performed depending upon the number of Undo levels configured in the Environment page of the Preferences Dialog See the section on Undoing for more information about GIMP s very sophisticated Undo functions The operation that has been undone is not lost immediately you can get it back by using the Redo command right away But if you perform another operation the Undo will be irretrievably lost Activating the Command e You can access this command from the image menubar through Edit Undo e by using the keyboard shortcut Ctrl Z e or by simply clicking on the status you want in the Undo History dialog Redo The Redo command reverses the effects of the Undo command Each Undo action can GNU Image Manipulation Program Page 222 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o be reversed by a single Redo action You can alternate Undo and Redo as many times as
55. Layers Dialog section but we will touch on some aspects of it here in relation to the layer properties that they display Each open image has at any time a single active drawable A drawable is a GIMP concept that includes layers but also several other types of things such as channels layer masks and the selection mask Basically a drawable is anything that can be drawn on with painting tools If a layer is currently active it is shown highlighted in the Layers dialog and its name is shown in the status area of the image window If not you can activate it by clicking on it If none of the layers are highlighted it means the active drawable is something other than a layer In the menubar above an image window you can find a menu called Layer containing a number of commands that affect the active layer of the image The same menu can be accessed by right clicking in the Layers dialog Layer properties Each layer in an image has a number of important attributes The Selection Often when you operate on an image you only want part of it to be affected In GIMP you make this happen by selecting that part Each image has a selection associated with it Most but not all GIMP operations act only on the selected portions of the image F There are many many situations where creating just the right selection is the key to getting the result you want and often it is not very easy to do For example in the above GNU Image
56. Manipulation Program Page 25 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o image suppose want to cut the tree out from its background and paste it into a different image In order to do this need to create a selection that contains the tree and nothing but the tree It is difficult because the tree has a very complex shape and in Now here is a very important point and it is crucial to understand this Ordinarily when you create a selection you see it as a dashed line enclosing a portion of the image The idea you could get from this Is that the selection is a sort of container with the selected parts of the image inside and the unselected parts outside This concept of the selection is okay for many purposes but it is not really correct Actually the selection is implemented as a channel In terms of its internal structure it is identical to the red green blue and alpha channels of an image Thus the selection has a value defined at each pixel of the image ranging between O unselected and 255 fully selected The advantage of this approach is that it allows some pixels to be partially selected by giving them intermediate values between O and 255 As you will see there are many situations where it is desirable to have smooth transitions between selected and unselected regions What then is the dashed line that appears when you create a selection It
57. Mask 1 sciection Mask 3 E selection Mask 2 f Selection Mask 1 E AME SE DE E E Channels can be used to save and restore your selections Clicking on the Quick mask button on the Image window automatically creates a new channel called Qmask and saves the displayed active selection to a thumbnail in front of the channel There are many selection tools in the Gimp like rectangular selection tool or fuzzy selection for continuous selections Selection Masks are a graphical way to build selections into a gray level channel where white pixels are selected and black pixels are not selected Therefore gray pixels are partially selected You can think of them as feathering the selection a smooth transition between selected and not selected This is important to avoid the ugly pixelization effect when you fill the selection or when you erase its content after isolating a subject from background GNU Image Manipulation Program Page 158 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o Using Selectionmasks Once the channel is initialized selected highlighted in blue visible eye icon in the dialog and displayed as you want color and opacity attributes you can start to work with all the paint tools The colors used are important If you paint with some color other than white grey or black the color Value luminosity will be used to define a gray medium light or dark
58. N E O O 2 S O xe a 2 xe o d 3 S o dragging guides from the image rulers and positioning them where you would like Activating the Command e You can access this command from the image menubar through Image Guides New Guide New Guide Options Script Arguments Direction Horizontal T Position o Script Progress none ra New Guides from Selection The New Guides from Selection command adds four guide lines one for each of the upper lower left and right edges of the current selection If there is no selection in the current image no guides are drawn Activating the Command e You can access this command from the image menubar through Image Guides New Guides from Selection Configure Grid The Configure Grid command lets you set the properties of the grid which you can display over your image while you are working on it The GIMP provides only Cartesian grids You can choose the color of the grid lines and the spacing and offsets from the origin of the image independently for the horizontal and vertical grid lines You can choose one of five different grid styles Activating the Command e You can access this command from the image menubar through Image Configure Grid Description of the Configure Grid dialog GNU Image Manipulation Program Page 257 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Appear
59. Options dialog appear four buttons e Save Options to This button allows you to save the settings for the current tool so that you can restore them later It brings up a small dialog allowing you to give a name to the array of saved options When you Restore options only saved sets for the active tool are shown so you need not worry about including the name of the tool when you assign a name here e Restore Options This button allows you to restore a previously saved set of options for the active tool If no option sets have ever been saved for the active tool the button will be insensitive Otherwise clicking it will bring up a menu showing the names of all Saved option sets choosing a menu entry will apply those settings e Delete Options This button allows you to delete a previously saved set of options for the active tool If no option sets have ever been saved for the active tool the button will be insensitive Otherwise clicking it will bring up a menu showing the names of all Saved option sets choosing a menu entry will delete those settings e Reset Options This button resets the options for the active tool to their default values GNU Image Manipulation Program Page 105 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o Selection Tools Common Features Selection tools are designed to select regions from images or layers so you can work on them witho
60. S o By using the Desaturate command you can convert all of the colors on the active layer to corresponding shades of gray This differs from converting the image to grayscale in two respects First it only operates on the active layer and second the colors on the layer are still RGB values with three components This means that you can paint on the layer or individual parts of it using color at a later time This command only works on layers of RGB images If the image is in Grayscale or Indexed mode the menu entry is insensitive and grayed out Activating the Command e You can access this command from the image menubar through Layer Colors Desaturate Invert The Invert command inverts all the pixel colors and brightness values in the current layer as if the image were converted into a negative Dark areas become bright and bright areas become dark Hues are replaced by their complementary colors For more information about colors see the Glossary entry about Color Model This command only works on layers of RGB and Grayscale images If the current image Is Indexed the menu entry is insensitive and grayed out Don t mix up this command with the Invert Selection command Activating the Command e You can access this command from the image menubar through Layer Colors Invert Example The Auto Submenu Equalize Color Enhance Normalize Stretch Contrast Stretch HSV The Auto submenu contains operations which
61. S o GNU Image Manipulation Program Page 18 of 421 Generated by docbook2odf E utah04 jpg 2 ki Auto By default a Layers Channels and Paths dock shows an Image Menu at the top and other types of docks do not You can always add or remove an Image Menu however using the Show Image Menu toggle in the Tab menu as described below Exception you cannot add an Image Menu to the dock that contains the Toolbox Tab Menu In each dialog you can access a special menu of tab related operations by pressing the Tab Menu button as highlighted in the figure on the right Exactly which commands are shown in the menu varies a bit from dialog to dialog but they always include operations for creating new tabs or closing or detaching tabs xe e N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 19 of 421 Generated by docbook2odf Layers Menu Add Tab X Close Tab 2 Detach Tab Preview Size Tab Style View as List View as Grid Show Image Menu Auto Follow Active Image The Tab menu gives you access to the following commands pe O N E O O 2 S O xe a 2 xe o 4 G d 0 S o GNU Image Manipulation Program Page 20 of 421 Generated by docbook2odf Basic GIMP Concepts This section is intended to give you a brief introduction to the basic concepts and terminology you will need to understand in order to make sense of the re
62. Upper Threshold MENN 25s Middle Value to Peaks Propagating Rate _ 1 00 C Foreground to Peaks Only Foreground To Top Only Background fy To Left ff To Right More Opaque f To Bottom More Transparent Overview This filter is found in Image gt Filters Distorts Value Propagate lt works on color borders It spreads pixels that have a Value between selected thresholds in selected directions Options Waves Mode Smear Blacken Reflective Parameter Settings Amplitude J 2222222 10 00 l Phase 7 0 00 E Wavelength 2 10 00 B Cancel Overview This filter is found in Image gt Filters Distorts Waves With this filter you get the same effect as a stone thrown in a quiet pond giving concentric waves Options Whirl and Pinch GNU Image Manipulation Program Page 356 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Whirl Angle A 20 00 f Pinch Amount o 0 000 Radius 1 000 l Overview This filter is found in Filters Distorts Whirl and Pinch Whirl and Pinch distorts your image in a concentric way Whirl distorts the image much like the little whirlpool that appears when you empty your bath Pinch can be compared to applying your image to a soft rubber surface and squeezing the edges or corners If the Pinch amount slider is set to a negative value it will look as
63. Windows does not come with such tools It is possible to set up a good software building environment in Windows but it requires either a substantial amount of money or a substantial amount of effort and knowledge What this means in relation to GIMP plugins is the following either you have an environment in which you can build software or you don t If you don t then your best hope is to find a precompiled version of the plugin somewhere or persuade somebody to compile it for you in which case you simply need to put it into your personal plugin directory If you do have an environment in which you can build software which for present purposes means an environment in which you can build GIMP then you no doubt already know quite a bit about these things and just need to follow the Linux instructions If you would like to set up a build environment and are ready for the heroism involved you can find a reasonably recent description of how to go about it in the GIMP Wiki at How loCompileGimp MicrosoftWindows Since it is a Wiki anybody Is free to edit it so please keep it up to date by adding advice based on your own experiences Macintosh We could use some material here Writing Plugins If you want to learn how to write a plugin you can find plenty of help at the GIMP Developers web site developer gimp org GIMP is a complex program but the development team has made strenuous efforts to flatten the learning curve for plugin wri
64. a JPEG expert the Quality parameter is probably the only one you will benefit from adjusting JPEG files from many digital cameras contain extra information called EXIF data specifying camera settings and other information concerning the circumstances under which the image was created Gimp s ability to handle EXIF data depends on whether the library libexif is available on your system it is not automatically packaged with Gimp If Gimp has been built with libexif support then EXIF data is preserved if you open an JPEG file work with the resulting image and then save as JPEG The EXIF data is not altered in any way when you do this which means that certain fields within it are no longer valid If Gimp is not built with EXIF support this does not prevent files with EXIF data from being opened but it means that the EXIF data will not be present when the resulting image Is later saved You can think of layers as a stack of slides or clothes on your body Each part of clothes you re wearing Is a layer in the layers dialog Layers are stacked on top of each other The GNU Image Manipulation Program Page 404 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o hn S o bottom layer is the background of the image and the components in the foreground of the image come above it Representation of an image with layers he final image T T a his term describes the dotted line
65. active layer and reduce the number of colors while maintaining a semblance of the original image characteristics Activate Tool The Posterize Dialog can be called in the following order from the image menu Tools Color Tools Posterize or by double cliking on the icon in ToolBox if Color Tools have been added to it GNU Image Manipulation Program Page 145 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Options Posterize Reduce Number of Colors Background 2 Untitled Posterize Levels L PO 3 Z Preview Reset X Cancel Pox pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 146 of 421 Generated by docbook2odf Other Path Tool The Path tool allows to create complex selections called Bezier Curves a bit like Lasso but with all the adaptability of vectorial curves You can edit your curve you can paint with your curve or even save import and export the curve You can also use paths to create geometrical figures Paths have their own dialog box Dialog Activate Tool e You can call the Path Tool in the following order from the image menu Tools Paths e The Tool can also be called by clicking the tool icon e or by using the B keyboard shortcut Key modifiers Defaults Options See The Path concept Color Picker Tool pe O N E O O 2 S
66. add other folders to the palette search path using the Palette Folders page of the Preferences dialog GIMP palettes are stored using a special file format in files with the extension gpl It isa very simple format and they are ASCII files so if you happen to obtain palettes from another source and would like to use them in GIMP it probably won t be very hard to convert them just take a look at any gpl and you will see what to do Colormap GNU Image Manipulation Program Page 38 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o Confusingly GIMP makes use of two types of palettes The more noticeable are the type shown in the Palettes dialog palettes that exist independently of any image The second type indexed palettes form the colormaps of indexed images Each indexed image has its own private indexed palette defining the set of colors available in the image the maximum number of colors allowed in an indexed palette is 256 These palettes are called indexed because each color is associated with an index number Actually the colors in ordinary palettes are numbered as well but the numbers have no functional significance Indexed Palette D E a Bi ta E al EH poe a E B Py Ta Pa a Aa _ B E T Fail E F E E E m aranana is sce sas e BEES a E E EEn 8 o_o fal TI OOOO O rl i 4 Aerie nat
67. affected pixels is determined by the Randomization option Options Spread GNU Image Manipulation Program Page 323 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Spread Amount Horizontal 5 q Vertical 5 px El Overview This filter is found in Filters Noise Spread The Spread filter swaps each pixel in the active layer or selection with another randomly chosen pixel by a user specified amount It works on color transitions not on plain color areas No new color is introduced Options pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 324 of 421 Generated by docbook2odf Edge detect filters Edge detect introduction Edge detect filters search for borders between different colors and so can detect contours of objects They are used to make selections and for many artistic purposes Most of them are based on gradient calculation methods and give thick border lines Look at fig 1 which represents color intensity variations On the left is a slow color gradient which is not a border On the right is a quick variation which is an edge Now let us calculate the gradient the variation speed of this edge i e the first derivative fig 2 We have to decide that a border is detected when gradient is more than a threshold value the exact border is at top of the curve but thi
68. allowing a transparency of on or off Other formats allow a variable level of transparency The smaller the alpha value of a pixel the more visible the color of the pixel on the level below it A pixel with an alpha value of O is completely transparent Antialiasing is the process of reversing an alias that is lessening the jaggies Antialiasing produces smoother curves by adjusting the boundary between the background and the pixel region that is being antialiased Generally pixel intensities or opacities are changed so a smoother merge with the background is achieved With selections the selection edge is affected so that the selection edge opacity is lowered n uncompressed bitmap format used by Microsoft Windows for displaying graphics Color depth is typically 1 4 or 8 bits although the format does Support more From The Free On line Dictionary of Computing 13 Mar 01 bitmap A data file or structure which corresponds bit for bit with an image displayed on a screen probably in the same format as it would be stored in the display s video memory or maybe as a device independent bitmap A bitmap is characterised by the width and height of the image in pixels and the number of bits per pixel which determines the number of shades of grey or colours it can represent A bitmap representing a coloured image a pixmap will usually have pixels with between one and eight bits for each of the red green and blue components though other c
69. already been fixed is just a waste of everybody s time GIMP 1 is no longer maintained so if you use it and find bugs either upgrade to GIMP 2 or live with them Particularly if you are using the development version of GIMP make sure that you can see the bug in the latest release before filing a report lf after due consideration you still think you have a legitimate bug report or enhancement request the next step is to go to GIMP s bugzilla query page http bugzilla gnome org query cgi and try to see whether somebody else has already reported the same thing The query page allows you to search the bug database in a variety of ways Unfortunately this page Is a bit more complicated to use than it really ought to be but here is basically what you should do When you have set these things up click on the Search button at either the top or bottom they both do the same thing The result is either a list of bug reports hopefully not too long or a message saying Zarro boogs found If you don t find a related bug report by doing this it may be worth trying another search with different terms If in spite of your best efforts you file a bug report and it ends up being resolved as Duplicate don t be too upset it has happened repeatedly to the author of this documentation who works with GIMP Bugzilla nearly every day GNU Image Manipulation Program Page 414 of 421 Generated by docbook2odf xe O N E O O 2 S O xe a
70. an alpha channel go to the channel dialog and verify that an entry for Alpha exists besides Red Green and Blue If this is not the case add a new alpha channel from the layers menu You can now remove the background layer to get a completely transparent background or create a gradient from color to transparency You are only limited by your imagination To demonstrate the cabilities of aloha transparency we ll make a soft glow in the background around our Wilber After you re done with your image you can save it in PNG format pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o GNU Image Manipulation Program Page 76 of 421 Generated by docbook2odf Adding New Brushes To add a new brush after either creating or downloading it you need to save it ina format GIMP can use The brush file needs to be placed in the GIMP s brush search path so that GIMP is able to index and display it in the Brushes dialog You can hit the Refresh button which reindexes the brush directory GIMP uses three file formats for brushes Spacing percent 20 m E m ooo Description GIMP Brush Pipe x 30 Pixels Cell size da Number of cells 1 Display as 1 Rows of 1 Columns on each layer Dimension Ranks random random random random E Help W cancel To make a brush available place it in one of the folders in GIMP s brush search path By default the brush search path includes two folders
71. an empty function and registered it with Gimp In this lesson we want to provide functionality to our script we want to create a new image add the user s text to it and resize the image to fit the text exactly Once you know how to set variables define functions and access list members the rest is all downhill all you need to do is familiarize yourself with the functions available in Gimp s procedural database and call those functions directly So fire up the DB Browser and let s get cookin Let s begin by making a new image We ll create a new variable theImage set to the result of calling Gimp s built in function gimp image new As you can see from the DB Browser the function gimp image new takes three parameters the image s width height and the type of image Because we ll later resize the image to fit the text we ll make a 10x10 RGB image We ll store the image s width and sizes in some variables too as we ll refer to and manipulate them later in the script BERRRREE define Sscript fu text boxinText inFont inFontsSizelinTextColor BERRREEE let TTT TT TTT a GNU Image Manipulation Program Page 93 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o BERR RRR BdefineWourllocalfivariables BERR BcreatcHallnewHimage BORER ChelmagewWidthill o BER RRR RRR RRR ChelmageHeight l10 BERR RRR tC helmagell carll eee og imp image new eee he lmageWidth
72. and 2 2 each text item goes in a separate Text layer and you can come back later to the layer and edit the text in it You can also move the text around in the image or change the font or the font size You can use any font available on your system You can control justification indentation and line spacing Actually you can operate on a text layer in the same ways as any other layer but doing so often means giving up the ability to edit the text without losing the results of your GNU Image Manipulation Program Page 39 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o work D ws Open Clear LTR To understand some of the idiosyncrasies of text handling it may help for you to realize that a text layer contains more information than the pixel data that you see it also contains a representation of the text in a text editor format You can see this in the text editor window that pops up while you are using the Text tool Every time you alter the text the image layer is redrawn to reflect your changes Now suppose you create a text layer and then operate on it in some way that does not involve the Text tool rotate it for example Suppose you then come back and try to edit it using the Text tool As soon as you edit the text the Text tool will redraw the layer wiping out the results of the operations you performed in the meantime Because this danger is not o
73. and you can scale and rotate the entire leaf 6 The final step is to adjust color Click on the Color Transformation tab and choose a different color for each fractal To do this check Simple and press the right color square A color circle appears where you can click or select to choose a color 7 Press OK to apply the image and voila you ve just made a perfect fractal leaf Now that you ve got the hang of it you ll just have to experiment and make your own designs All plant imitating fractals be they oak trees ferns or straws are more or less made in this fashion which is leaves around a stem or several stems You just have to twist another way stretch and turn a little or add a few more fractals to get a totally different plant Diffraction Patterns pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o GNU Image Manipulation Program Page 388 of 421 Generated by docbook2odf Frequencies Red L ne fosis K Green M M jia G Preven Sve N A 2 123 E Overview This filter is found in Filters Render Patterns Diffraction Patterns This filter lets you make diffraction or wave interference textures You can change the Frequency Contours and Sharp Edges for each of the RGB channels You can also set Brightness Scattering and Polarization of the texture There is no automatic preview so you must press the preview button to update On a slow system this may take a bit of time Thi
74. appear in any index can be assigned any color In an Indexed image instead of being assigned a color directly as happens in RGB and Grayscale images each pixel is assigned an index To determine the color that should be Shown for that pixel GIMP looks up the index in the image s colormap Each indexed image has its own private colormap It is important to realize that the colors in the colormap are the only colors available for an indexed image that is unless you add new colors to the colormap This has a major effect on many gimp operations for example in a pattern fill GIMP will usually not be able to find exactly the right colors in the colormap so it will approximate them by Dithering If the colormap is too limited or poorly chosen this can easily produce very poor image quality The Colormap dialog allows you to alter the colormap for an image either by creating new entries or by changing the colors for the existing entries If you change the color associated with a given index you will see the changes reflected throughout the image as a color shift for all pixels that are assigned that index The entries are numbered with O in the upper left corner 1 to its right etc Using the Colormap dialog Here are the operations you can perform using this dialog If you make a mistake you can undo it by focusing the pointer in the image whose colormap you have changed and then pressing Ctrl Z or choosing Edit Undo in the image m
75. are removed If the active layer has an alpha channel the deleted selection is made transparent You can restore the original color to the transparent area using the Eraser tool by setting it to Anti Erase If the layer does not have an alpha channel the deleted area is filled using the current background color Clearing a selection does not delete the selection itself Unlike Cut Clear does not place the deleted contents in the Clipboard and the contents of the clipboard are unaffected Activating the Command e You can access this command from the image menubar through Edit Clear e or by using the keyboard shortcut Ctrl K Fill with FG Color The Fill with FG Color command fills the image s selection with the solid color shown in the foreground part of the Color Area of the Toolbox The color is also shown to the left of the menu entry If some areas of the image are only partially selected for example as a result of feathering the selection they are filled in proportion to how much they are selected Please note that if the image has no selection the whole active layer is filled Activating the Command e You can access this command from the image menubar through Edit Fill with FG Color e or by using the keyboard shortcut Ctrl You can also fill a selection by click and dragging from the Toolbox foreground color Fill with BG Color The Fill with BG Color command fills the active layer selection with the solid c
76. automatically adjust the distribution of colors in the active layer without requiring any input from the user Several of these GNU Image Manipulation Program Page 265 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o operations are actually implemented as plugins Activating the submenu e You can access this submenu from the image window through Layer Colors Auto Contents of the Auto Submenu The Auto submenu contains the following entries Equalize The Equalize command stretches every R G and B component between 0 and 255 The results of this command can vary quite a bit Sometimes Equalize works very well to enhance the contrast in an image bringing out details which were hard to see before Other times the results look very bad It is a very powerful operation and it is worth trying it to see if it will improve your image Activating the Command e You can access this command from the image menubar through Layer Colors Auto Equalize e or by using the keyboard shortcut Shift Page Down Example GNU Image Manipulation Program Page 266 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 3 S o Mean 81 1 Pixels 126000 Std Dev 12 0 Count 126000 Median 66 0 Percentile 100 0 Histogram Background Channel RGB k Mean 128 6 Pixels Std Dev 21 8 Count Median 129 0 Percentile
77. by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o Status Bar Informations are displayed in the status bar at the bottom of the Image window The status bar shows a pair of numbers The first number is the distance between the origine point and the mouse pointer Mostly the measure unit is shown as Pixel The second number is the angle in every quadrant from 0 to 90 Activate Tool e You can call the Measure Tool in the following order from the image menu Tools Measure e You can also access to it by clicking the tool icon Key modifiers Options Measuring surfaces You can t measure surfaces directly but you can use the Histogram that gives you the number of pixels in a selection Texttool The Text tool places text into an image When you click on an image with this tool the Text Editor dialog is opened where you can type your text and a text layer is added in the Layer Dialog In the Text Option dialog you can change the font color and size of your text and justify it interactively Activate Tool e The Text Tool can be called in the following order from the image menu Tools Text e The Tool can also be called by clicking the tool icon e or by using the T keyboard shortcut Options GNU Image Manipulation Program Page 150 of 421 Generated by docbook2odf xe e N E O O 2 0 O xo a 2 xe o 4 d 3 S o Text Editor GNU I
78. by toggling View Show Guides It is suggested that you only do this momentarily otherwise you may get confused the next time you try to create a guide and don t see anything happening If it makes things easier for you you can change the default behavior for guides in the GNU Image Manipulation Program Page 30 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Image Window Appearance page of the Preferences dialog Disabling Show guides is probably a bad idea though for the reason just given Another use for guides the Guillotine plugin can use guides to slice an image into a set of Sub images See also Guides in Glossary Paths A path is a one dimensional curve Paths are used for two main purposes e A closed path can be converted into a selection e An open or closed path can be stroked that is painted on the image in a variety of ways Paths can be created and manipulated using the Path tool Paths like layers and channels are components of an image When an Image is saved in GIMP s native XCF file format any paths it has are saved along with it The list of paths in an image can be viewed and operated on using the Paths dialog If you want to move a path from one image to another you can do so by copying and pasting using the popup menu in the Paths dialog or by dragging an icon from the Paths dialog into the destination image s window xe e
79. can see this in the Color Area of the Toolbox If you hold down the Ctrl key while clicking GIMP s background color will be set to the selected color Double clicking on a color not only sets the foreground it also brings up a color editor that allows you to modify the selected palette entry This only happens if the palette is one you are allowed to modify that is one you have added to GIMP yourself Right clicking in the palette display area brings up the Palette Editor menu It s functions are mainly the same as those of the buttons at the bottom of the dialog Below the palette display area at the left appears a text entry area that shows the name GNU Image Manipulation Program Page 174 of 421 Generated by docbook2odf y xe O N E O O 2 S O xe a 2 xe o d 3 S o of the selected color or Unnamed if it does not have one This information has no functional significance and is present only to serve you aS a memory aid To the right of the name entry is a spinbutton that allows you to set the number of columns used to display the palette This only affects the display not how the palette works If the value is set to 0 a default will be used At the bottom of the dialog are a set of buttons which mostly match the entries in the Palette Editor menu accessible by right clicking in the palette display area Here are the buttons Palette Editor Menu Ei Edit Color E New Color from FG
80. command with a O radius Border Lo ke e N xX e e 2 o e ke gt 2 3 0 E d hn o LU GNU Image Manipulation Program Page 234 of 421 Generated by docbook2odf I li I I I I l I 1 I I The Select Border command creates a new selection along the edge of an existing selection in the current image The edge of the current selection is used as a form and the new selection is then created around it You enter the width of the border in pixels or some other unit in the dialog window Half of the new border lies inside of the selected area and half outside of it Activating the Command e You can access this command from the image menubar through Select Border Description of the Border dialog window Border selection by e J E a pixels a Rounded Rectangle This script fu converts a selection rectangular elliptic or else to a rectangular selection with rounded corners The Radius is a percentage of half the selection width or height whichever the smaller Select Concave if you want round edges to be indented Rounded Rectangle works by adding circles to or subtracting circles from the selection Activate Dialog e This command is found at Select Rounded Rectangle Options Script Arguments Radius 37 Concave Script Progress lfa cancel Box GNU Image Manipulation Program age 235 of 421 Generated by docbook2odf pe O N E O O 2 S O
81. determines many aspects of the appearance of the GIMP user interface including the set of icons used their sizes fonts spacing allowed in dialogs etc Two themes are supplied with GIMP Default which is probably best for most people and Small which may be preferable for those with small or low resolution monitors Clicking on a theme in the list causes it to be applied immediately so it is easy to see the result and change your mind if you don t like it You can also use custom themes either by downloading them from the net or by copying one of the supplied themes and modifying it Custom themes should be places in the themes Subdirectory of your personal GIMP directory if they are they will appear in the list here Each theme is actually a directory containing ASCII files that you can edit They are pretty complicated and the meaning of the contents goes beyond the scope of this documentation but you should feel free to experiment in the worst case if you mess things up completely you can always revert back to one of the supplied themes You cannot edit the supplied themes unless you have administrator permissions and even if you do you shouldn t if you want to customize a theme make a copy in your personal directory and work on it If you make a change and would like to see the result on the fly you can do so by saving the edited theme file and then pressing Reload Current Theme Help System pe O N E O O 2 S
82. e The Dodge or Burn Tool can be called in the following order from the image menu Tools Paint Tools DodgeBurn e The Tool can also be called by clicking the tool icon Key modifiers Defaults Options GNU Image Manipulation Program Page 128 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Opacity 1 1000 Mode Normal Brush Pressure Sensitivity Opaciy Hardness Size Fade out Length 100 px Hard edge Type Ctr Dodge C Burn Mode O Shadows Midtones C Highlights Exposure M Jun 500 E See the Brush Tools Overview for a description of tool options that apply to many or all brush tools Smudge Tool The Smudge tool uses the current brush to smudge colors on the active layer ora selection It takes color in passing and uses it to mix it to the next colors it meets ona distance you can set Activate Tool e The Smudge Tool can be called in the following order from the image menu Tools Paint Tools Smudge e The Tool can also be called by clicking the tool icon GNU Image Manipulation Program Page 129 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o e or by pressing the S key on keyboard Key modifiers Defaults Options Wonnal Brush oO Circle 11 b Pressure sensitivity Fade out Hard edge Rate See the Bru
83. eee he lImageHeight eee RERCe ETT eee TTT BERR RRR cheText ENNEN adeclaration foritheltext ee wecreatecHlater PTT TTY Note We used the value RGB to specify that the image is an RGB image We could have also used 0 but RGB is more descriptive when we glance at the code You should also notice that we took the head of the result of the function call This may seem strange because the database explicitly tells us that it returns only one value the ID of the newly created image However all Gimp functions return a list even if there is only one element in the list so we need to get the head of the list Adding A New Layer To The Image Now that we have an image we need to add a layer to it We ll call the gimp layer new function to create the layer passing in the ID of the image we just created From now on instead of listing the complete function we ll only list the lines we re adding to it You can see the complete script here Because we ve declared all of the local variables we ll use we ll also close the parentheses marking the end of our variable declarations BRRRRRRE createcHalnewllayerforiitheliimage BERR RRRRREE cheLayer SR Car eee Gg imp layer new ORR he limage eee he lmagewidth Oe heImageHeight Oe RCB IMAGE eee Payer eee OO Oe NORMAL eee ORR PTT TTT BRRRRRREE 8 endoffourlocalivariables EEEEHE Once we have the new layer we need to add it to the image EEEEHEE gimp image
84. effect of the Shift key alone except that the orientation of the line is constrained to the nearest multiple of 15 degrees Use this if you want to create perfect horizontal vertical or diagonal lines Tool Options Opacity 7 _1_ 1000 f Mode Normal E Brush b Pressure sensitivity Fade out Length 100 px Incremental Hard edge Many tool options are shared by several brush tools these are described here Options that apply only to one specific tool or to a small number of tools are described in the sections devoted to those tools Further Information Advanced users may be interested to know that brush tools actually operate at a sub pixel level in order to avoid producing jagged looking results One consequence of this is that even if you work with a hard edged brush such as one of the Circle brushes pixels on the edge of the brushstroke will only be partially affected If you need to have all or nothing effects which may be necessary for getting a good selection or for cutting and pasting or for operating pixel by pixel at a high zoom level there are two things you can do 1 for painting use the Pencil tool which makes all brushes perfectly hard and disables sub pixel anti aliasing or 2 for other types of brush tools check the Hard edge box in the Tool Options Bucket Fill GNU Image Manipulation Program Page 116 of 421 Generated by docbook2odf pe O N E O O 2
85. everything you need This tool is often useful for images that are overexposed or underexposed it is not useful for correcting color casts The tool gives you two sliders to adjust for Brightness and Contrast If you have the option Preview checked and almost certainly you should you will see any adjustments you make reflected in the image When you are happy with the results press Okay and they will take effect If you can t get results that you are happy with press Cancel and the image will revert to its previous state A more sophisticated and only slightly more difficult way of correcting exposure problems is to use the Levels tool The dialog for this tool looks very complicated but for the basic usage we have in mind here the only part you need to deal with is the Input Levels area specifically the three triangular sliders that appear below the histogram We refer you to the Levels Tool Help for instructions but actually the easiest way to learn how to use it is to experiment by moving the three sliders around and watching how the image Is affected Make sure that Preview is checked at the bottom of the dialog GNU Image Manipulation Program Page 69 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o A very powerful way of correcting exposure problems is to use the Curves tool This tool allows you to click and drag control points on a curve in order to create
86. exchange one color range to another range Main Options You have there two color circles one for the From color range and the other for the To color range Grey Options 540 LOO Ath ra ah 20 Samm 0 Sat 5096 Sate 25 yi In this tab you can specify how to treat gray By default grey is not considered as a color and is not taken in account by the rotation Here you can convert slightly saturated colors into grey and you can also convert grey into color Previews Units You can select here the angle unit used to locate colors in the Hue Saturation circle This choice is valid only for the current filter session don t click on Valid just after selecting unit return to the wanted tab Map Color Range t 3 o N x o e 2 8 o 3 gt 2 a o Ww hn o c o GNU Image Manipulation Program Page 302 of 421 Generated by docbook2odf Source color range som Mo Destination color BEEE a Cancel Overview Lo ke e N xX e e 2 o e ke gt 2 3 0 Ww hn o GNU Image Manipulation Program Page 303 of 421 Generated by docbook2odf oy ale This filter is found in Filters Colors Map Color Range Mapping Unlike Exchange filter Map Color Range maps a defined color range against another defined color range Options Sample Colorize Settings Destination I untitied 2 Background 4 Sample From Gradient W Show Selection W Show Col
87. format If your image contains fewer colors that is if it is not a photograph but is more a drawing you created such as a button or a screenshot you would be better off using PNG format We will guide you through the process of doing this First open the image as usual have opened our Wilber as an example image The image is now in RGB mode with an additional Alpha channel RGBA There is usually no need to have an alpha channel for your web image You can remove the alpha channel by flattening the image If you open a photograph you probably won t have to remove the alpha channel because a photograph doesn t usually have one so the file is already opened in RGB mode After you have flattened the image you are able to save the image in PNG format for your web site You can save your image in PNG format with the default settings but using maximum compression Doing this will have no negative affects on the quality of the picture as it would have with JPEG format If your image is a photograph with lots of colors you would be better off saving it as jpeg The main thing Is to find the best tradeoff between quality and compression You can find more information about this topic in Reducing the File Size Even More If you want to reduce the size of your image a bit more you could convert your image to Indexed mode That means that all of the colors will be reduced to only 256 values Converting images with smooth color tra
88. found in Filters Light Effectsender Gflare Gflare effect reminds the effect you get when you take a photograph of a blinding light source with a halo and radiations around the source The Gflare image has three components Glow which is the big central fireball Rays and Second Flares Options The Settings tab allows you to set manually the parameters while the Selector tab let you choose presets in a list Settings Selector The Selector tab allows you to select a Gflare pattern to change it and save it Gflare Editor GNU Image Manipulation Program Page 343 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o a GFlare Editor Preview General Glow Rays Second Flares POPPE rrr a Glow Paint Options Opacity 100 0 Paint Mode Normal qd Rays Paint Options Opacity 100 0 Paint Mode Normal J Second Flares Paint Options Opacity 75 0 Paint Mode Screen Rescan Gradients Cancel Pox Lighting Effects Preview Options Light Material Bump Map Environment Map Intensity Levels Ambient 10 30 B Diffuse amp 1 00 B wal Reflectivity Diffuse 0 40 ill Specular g 0 60 B il Preview Options _ Highlight wa 127 00 a up date Interactive Overview y ao O N E O O 2 S O xe a 2 xo Q 4 hn S o GNU Image Manipulation Program Page 344 of 421 Gene
89. highlighted in the adjoining figure These are thin gray bars very unobtrusive and easy not to notice most people don t realize that they GNU Image Manipulation Program Page 17 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o exist until they are specifically pointed out Docking Drag Handles Each dockable dialog has a drag handle area as highlighted in the figure on the right You can recognize this by the fact that the cursor changes to a hand shape when the pointer is over the drag handle area To dock a dialog you simply click on its drag handle area and drag it onto one of the docking bars in a dock You can drag more than one dialog onto the same docking bar If you do they will turn into tabs represented by iconic symbols at the top Clicking on the tab handle will bring a tab to the front so that you can interact with it Image Menu Some docks contain an Image Menu a menu listing all of the images open in GIMP and displaying the name of the image whose information is shown in the dock You can use the Image Menu to select a different image don t confuse this menu for the Image Menu that is the Menu of the active image on your screen If the Auto button is depressed then the menu always shows the name of GIMP s currently active image that is the image you are currently working on pe O N E O O 2 S O xe a 2 xe o G d 9
90. hue BP rc to BG HSV counter clockwi I FG to BG RGB FG to Transparent abstract 1 PD J abstract 2 abstract 3 GE neu rism The Gradients dialog offers a gradient palette which is used to select a gradient a set of colors arranged in a linear scale for use with the Blend tool and numerous other operations It also gives you access to several functions for manipulating gradients You can select a gradient by clicking on it in the list it will then be shown in the Brush Pattern Gradient area of the Toolbox A few dozen nice gradients come pre installed with GIMP You can create more using the Gradient Editor General information about gradients and how they are used in GIMP can be found in the Gradients section The first four gradients are particular they reproduce the gradient between Foreground and background colors of toolbox in different ways Activate Dialog The Gradients dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in several ways GNU Image Manipulation Program Page 170 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o e From the Toolbox menu File Dialogs Gradients e From the Toolbox menu File Dialogs Create New Dock Brushes Patterns and Gradients This gives you a dock containing three dialogs with the Gradients dialog one of them e From the Toolbox by cl
91. if someone tried to push a round object up toward you from behind the rubber skin If the Pinch amount is set to a positive value it looks like someone is dragging or sucking on the surface from behind and away from you The pinch effect can sometimes be used to compensate for image distortion produced by telephoto or fisheye lenses barrel distortion AO T S S S S S S S S ee ee es ee GNU Image Manipulation Program Page 357 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o 4 HS ee H Parameter Settings Edge Affected Leading Trailing C Both Threshold i 10 g Strength _ as 10 g Cancel Overview This filter is found in Image gt Filters Distorts Wind The Wind filter can be used to create motion blur but it can also be used as a general distort filter What is characteristic about this filter is that it will render thin black or white lines Wind will detect the edges in the image and stretch out thin white or black lines from that edge This is why you can create the illusion of motion because the edges are what will be blurred in a photograph of a moving object Parameter Settings The interface is quite simple You can set the Strength of the wind and a Threshold value Threshold will restrict the effect to fewer areas of the image Strength controls the GNU Image Manipulation Program Page 358 of 421 Gene
92. if your image holds an Alpha channel lt Image gt Layers Transparency Add an alpha channel Otherwise it is greyed out The Semi flatten filter helps those in need of a solution to anti aliasing indexed images with transparency The GIF indexed format supports complete transparency 0 or 255 aloha value but not semi transparency 1 254 semi transparent pixels will be transformed to no transparency or complete transparency ruining anti aliasing you applied to the logo you want to put onto your Web page Before applying the filter it s essential that you should know the background color of your Web page Use the color picker to determine the exact color which pops up as the Foreground color of the Toolbox Invert FG BG colors so that BG color is the same as Web background color Semi flatten process will combine FG color to layer logo color proportionally to corresponding alpha values and will rebuild correct anti aliasing Completely transparent pixels will not take the color Very transparent pixels will take a few color and weakly transparent will take much color Smooth Palette Parameter Settings Width ese B Height 64 l Search Depth 50 Cancel Pox z m F px Overview GNU Image Manipulation Program Page 318 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o LANN hig fk i m m i LeeLee i T i a es
93. if the fancy takes you you can build a custom filter What is a convolution matrix It s possible to get a rough idea of it without using mathematical tools that only a few ones know Convolution is the treatment of a matrix by another one which is called kernel The Convolution Matrix filter uses a first matrix which is the Image to be treated The Image Is a bi dimensional collection of pixels in rectangular coordinates The used kernel depends on the effect you want GIMP uses 5x5 or 3x3 matrices We will consider only 3x3 matrices they are the most used and they are enough for all effects you want If all border values of a kernel are set to zero then system will consider it as a 3x3 matrix The filter studies successively every pixel of the image For each of them which we will call the initial pixel it multiplies the value of this pixel and values of the 8 surrounding pixels by the kernel corresponding value Then it adds the results and the initial pixel is set to this final result value A simple example GNU Image Manipulation Program Page 333 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o On the left is the image matrix each pixel is marked with its value The initial pixel has a red border The kernel action area has a green border In the middle is the kernel and on the right is the convolution result Here is what happened the filter read succe
94. image or the rotation point Activate Tool e You can call the Rotate tool in the following order from the image menu Tools Transform Tools Rotate e The Tool can also be called by clicking the tool icon in the Toolbox e or by using the ShiftR key combination GNU Image Manipulation Program Page 133 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o Key modifiers Defaults Rotation tool options The Rotation Information dialog window Scale Tool Overview The Scale Tool is used to scale layers selections or paths the Object When you click on image with the tool the Scaling Information dialog box is opened allowing to change separately Width and Height At the same time a Preview with a grid or an outline is Superimposed on the object and handles appear on corners that you can click and drag to change these dimensions A small circle appears at center of the Preview allowing to move this preview Activate Tool e The Scale Tool can be called in the following order from the image menu Tools Transform Tools Scale e The Tool can also be called by clicking the tool icon e or by using the Shift T key combination Key modifiers Defaults Options pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 134 of 421 Generated by docbook2odf Scale Affect Al Transform Direction
95. image menu under Filters Blur Selective Gaussian Blur Contrary to the other blur plug ins the Selective Gaussian Blur plug in doesn t act on all pixels blur is applied only if the difference between its value and the value of the Surrounding pixels is less than a defined Delta value So contrasts are preserved because difference is high on contrast limits It is used to blur a background so that the foreground subject will stand out better This add a sense of depth to the image with only a single operation Options Parameter Settings Blur Radius 5 00 B Max Delta P_I 50 Cancel Motion Blur Overview GNU Image Manipulation Program Page 292 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o Gn ao e N x e e 2 0 e a 2 ao eo w ther 9 S 9 GNU Image Manipulation Program Page 293 of 421 Generated by docbook2odf You can find this filter in the image menu under Filters Blur Motion Blur The Motion Blur filter creates a movement blur The filter is capable of Linear Radial and Zoom movements Each of these movements can be further adjusted with Length or Angle settings available Options Blur Type Linear C0 Radial C Zoom Blur Parameters Length baa 5 Angle p a5 Pixelise Overview GNU Image Manipulation Program Page 294 of 421 Generated by docbook2odf o l 3 o N x e o
96. in GIMP A frequent source of confusion occurs on Windows systems when GIMP encounters a malformed font file and generates an error message this causes a console window to pop up so that you can see the message Do not close that console window It is harmless and closing it will shut down GIMP When this happens it often seems to users that GIMP has crashed It hasn t closing the console window causes Windows to shut GIMP down Unfortunately this annoying situation is caused by an interaction between Windows and the libraries that GIMP links to it cannot be fixed within GIMP All you need to do though if this happens is minimize the console window and ignore it pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 81 of 421 Generated by docbook2odf Rendering a Grid How can you create a grid that Is actually part of the image You can t do this using the image grid that is only an aid and is only visible on the monitor or in a screenshot You can however use the Grid plugin to render a grid very similar to the image grid Actually the plugin has substantially more options See also Grid and Guides pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 82 of 421 Generated by docbook2odf A Script Fu Tutorial In this training course we ll introduce you to the fundamentals of Scheme necessary to use S
97. in the glossary The browser is most useful for advanced users who write scripts or plug ins Activating the Command e You can access this command from the toolbox menubar through Xtns Procedure Browser Description of the Procedure Browser dialog window GNU Image Manipulation Program Page 211 of 421 Generated by docbook2odf y xe e N E O O 2 S O xe a 2 xe o d 3 S o B52 Procedures extension gimp help exlension gimp help GIMP Extension extensicn_gmp help browser Parameters extension script fu nur domain names INT32 a dorain names STRAINGARRA Y filc_bmp_loas nun doanain ris INT 32 file brap save dor ain_uns STAIN GAARA Y tle _bz2 Ipad Additional Information file bz2 save Author Sven Neumann lt svenaging org Michael T lt ritchaginp orgs Henris Brix Ancersen t Dele 1999 27074 Copyright Sve c Neumann ccael Matterer amp Henris Ri file cel Ina file_ccl save The figure above shows the Procedure Browser dialog window If you click on an item in the scrolled list on the left information about it is displayed on the right You can also search for a specific procedure by name by entering part or all of the name of the procedure in the Search text box and clicking on the Search by Name button or search for one by its description by entering a search string in the Search text box and clicking on the Search by Blurb button The Script Fu submenu Buttons Logos
98. it jumps to the opposite edge and continues as though the pattern were repeated side by side indefinitely When you clone from an image this does not happen if you go beyond the edges of the source the Clone tool stops producing any changes You can clone from any drawable that is any layer layer mask or channel to any other drawable You can even clone to or from the selection mask by switching to QuickMask mode If this means copying colors that the target does not support for example cloning from an RGB layer to an Indexed layer or a layer mask then the colors will be converted to the closest possible approximations How to Activate he Clone tool can be activated from an image menu as Tools Paint Tools Clone from he Toolbox by clicking on the tool icon or from the keyboard using the shortcut c or S under GIMP 2 10 Key modifiers See the Brush Tools Overview for a description of key modifiers that have the same effect on all brush tools Tool Options Mode Normal Brush Pressure sensitivity fv Opacity Hardness Size Fade out Length 100 px Hard edge Pattern ii Source fe Image source Pattern source Alignment Non aligned Aligned C Registered See the Brush Tools Overview for a description of tool options that apply to many or all brush tools Further Information xe e N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Ma
99. layer mask to the active layer It displays a dialog in which you can set the initial properties of the mask If the layer already has a layer mask or if it cannot have one because it does not have an alpha channel the menu entry is Insensitive and grayed out A layer mask lets you define which parts of the layer are opaque semi transparent or transparent See the Layer Mask section for more information Activating the Command e You can access this command from the image menubar through Layer Mask Add Layer Mask e or from the pop up menu you get by right clicking on the active layer in the Layers Dialog Description of the Add Layer Mask Dialog L Add a Mask to the L BY Aa ayers ura Initialize Layer Mask to fe White full opacity Black full transparency Layers alpha channel Transfer layers alpha channel Selection C Grayscale copy of layer Invert Mask When you click on the OK button a thumbnail of the layer mask appears to the right of the thumbnail of the layer in the Layers Dialog GNU Image Manipulation Program Page 269 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Apply Layer Mask The Apply Layer Mask command merges the layer mask with the active layer The transparency information in the layer mask is transferred to the alpha channel and the layer mask is removed If the active layer does not have a layer mask the menu entr
100. o ww hn o c o GNU Image Manipulation Program Page 282 of 421 Generated by docbook2odf Tools Introduction to the Tools Menu Toolbox E Default Colors a Swap Colors Selection Tools Paint Tools Transform Tools Color Tools a Paths amp Color Picker JA Magnify A Measure T Text The menu entries on the Tools menu access the GIMP tools All of the tools available in GIMP are extensively described in the Toolbox section pe O N E O O 2 S O xe a 2 xe o 4 G d 0 S o GNU Image Manipulation Program Page 283 of 421 Generated by docbook2odf The Filters Menu of the Image Window Introduction to the Filters menu a Repeat Semi Flatten Re show Semi Flatten Shiftt Ctr F a Reset all Filters Blur Colors Noise Edge Detect Enhance Generic Glass Effects Light Effects Distorts Artistic Map Render Web Animation Combine Toys In GIMP terminology a fi ter is a plug in that modifies the appearance of an image in most cases just the active layer of the image Not all of the entries in this menu meet that definition however the word filter is often mis used to mean any plug in regardless of what it does Indeed some of the entries in this menu do not modify images at all With the exception of the top three items of the Filters menu all of the entries are provided by plug ins Each plug in decides for itself where it would like its
101. o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o Enhance filters Enhance filters introduction Enhance filters are used to compensate for image Imperfections Such imperfections include dust particles noise interlaced frames coming usually from a TV frame grabber and insufficient sharpness Deinterlace Mode C Keep Odd Fields a Cancel Overview This filter is found in Image gt Filters Enhance Deinterlace Images captured by videocards especially when fast movement is recorded may look blurred and stripped with splitted objects This is due to how cameras work They don t record 25 images per second but 50 with half vertical resolution There are two interlaced images in one frame First line of first image is followed by first line of second image followed by second line of first image etc So if there have been an important move between the two images objects will appear splitted shifted stripped The Deinterlace filter keeps only one of both images and replaces missing lines by a gradient between previous and following lines The resulting image or selection will be somewhat blurred but can be improved by enhance filters A test Image can be found at www alparysoft com Options Despeckle GNU Image Manipulation Program Page 328 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o Type W Adaptive Recursive
102. of the basic color is first performed in some systems The chrominance signals and also the color difference signals contain the color information They are formed by the difference of blue minus luma or red minus luma U B Y V R Y From the three generated components Y U and V the individual color proportions of the basic color can be calculated again later GNU Image Manipulation Program Page 408 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 hn 0 S o Y U Y B Y Y Y B B Y V Y R Y Y Y R R Y B R R G B B R G Furthermore because of the construction of the retina of the human eye it turns out that the brightness information is perceived at a higher resolution that the color so that many formats based on the YUV color model compress the chrominance to save on the bandwidth during transmission pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 409 of 421 Generated by docbook2odf The very beginning According to Peter Mattis and Spencer Kimball the original creators of GIMP in their announcement of GIMP 0 54 The GIMP arose from the ashes of a hideously crafted cs164 compilers class project The setting early morning We were both weary from lack of sleep and the terrible strain of programming a compiler in LISP The limits of our patience had long been exceeded and yet still the dam held And
103. on both the Toolbox window and the image window Only some of the menu items in these two menus are the same The contents of the File menu on your computer may have different entries than the ones shown here These entries are not part of the GIMP itself but are added by some of the plug ins You can get more information about any of these items by reading the documentation about the plug in it belongs to New Using the New Image dialog you can create a new empty image and set its properties The image is shown in a new image window You may have more than one image on your screen at the same time You can access the command from either the Toolbox menubar or the Image menubar through File New or by using the keyboard shortcut Ctrl N GNU Image Manipulation Program Page 215 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Open The Open command activates a dialog that lets you load an existing image from your hard drive or an external medium For alternative and sometimes more convenient ways of opening files see the Files section Activating the Dialog e You can access the Open dialog from the toolbox window or from an image window through File Open e You can also open the Dialog by using the keyboard shortcut CtrlO File browsing The left panel is divided into two parts The upper part lists your main directories and your storage devices yo
104. or curved A path all of whose segments are straight is called polygonal When you create a path segment it starts out straight because the handles for the anchor points are initially placed directly on top of the anchor points yielding handles of zero length which produce straight line segments You can make a segment curved by dragging a handle away from one of the anchor points One nice thing about paths is that they are very light in terms of resource consumption especially in comparison with images Representing a path in RAM only requires storing the coordinates of its anchors and handles 1K of memory is enough to hold quite a complex path but not enough to hold even a 20x20 pixel RGB layer Therefore it is quite possible to have literally hundreds of paths in an image without putting any significant stress of your system How much stress managing them would put on you is of course another question Even a path with thousands of segments consumes minimal resources in comparison to a typical layer or channel Paths and Selections GIMP lets you transform the selection for an image into a path it also lets you transform paths into selections For information about the selection and how it works see the Selection section When you transform a selection into a path the path closely follows the marching ants Now the selection is a two dimensional entity but a path is a one dimensional entity so there is no way to transform t
105. order from the image menu Tools Paint Tools Ink e You can also call this Tool by clicking on the tool icon GNU Image Manipulation Program Page 124 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o g Key modifiers Defaults Options See the Brush Tools Overview for a description of tool options that apply to many or all brush tools Clone Tool The Clone tool uses the current brush to copy from an image or pattern It has many uses one of the most important is to repair problem areas in digital photos by painting over them with pixel data from other areas This technique takes a while to learn but in the hands of a skilled user it is very powerful Another important use is to draw patterned lines or curves see Patterns for examples lf you want to clone from an image instead of a pattern you must tell GIMP which image you want to copy from You do this by holding down the Ctrl key and clicking in the desired source image Until you have set the source in this way you will not be able to paint with the Clone tool the tool cursor tells you this by showing a forbidden symbol pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 125 of 421 Generated by docbook2odf If you clone from a pattern the pattern is tiled that is when the point you are copying from moves past one of the edges
106. outline can be dragged to change the viewing region Activate the dialog The Navigation window dialog can be called in many ways e from the toolbox menu File Dialogs Navigation e from the image menu Dialogs Navigation e from the image menu View Navigation window the Shift Ctril N will call the Navigation Window e from another dialog menu Add Tab Navigation Pou can access more quickly to it but without the zoom functions by clicking on the icon at the right bottom corner of the image window Using the Navigation Dialog Undo History dialog Undo History This dialog shows you a list of the actions you have most recently performed on an image with a small sketch that attempts to illustrate the changes produced by each You can revert the image to any point in its Undo History simply by clicking on the right entry in the list For more information on GIMP s Undo mechanism and how it works see the section on Undoing Activate the dialog The Undo History dialog is a dockable dialog see the section on Dialogs and Docking for o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 165 of 421 Generated by docbook2odf help on manipulating it It can be activated in several ways From the Toolbox menu File Dialogs Undo History From the Toolbox menu File Dialogs Create New Dock Layers Channels and Paths This gives you a dock containing four di
107. painting the selection is the easiest and most effective way to delicately manipulate it To save the selection done by the Quickmask to a new channel Make sure that there is a selection and that Quickmask is not active in the image window Select in the image menu Select Save to Channel This will create a new channel in the channel dialog called SelectionMask 1 When QuickMask Is active Cut and Paste act on the selection rather than the image You can sometimes make use of this as the most convenient way of transferring a selection from one image to another GNU Image Manipulation Program Page 24 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o G d 3 S o You can learn more on Quickmask and Selection masks in the section dedicated to the channel dialog Layers A good way to visualize a GIMP image Is as a stack of transparencies in GIMP terminology each individual transparency is called a layer There is no limit in principle to the number of layers an image can have only the amount of memory available on the system It is not uncommon for advanced users to work with images containing dozens of layers The organization of layers in an image is shown by the Layers dialog which is the second most important type of dialog window in GIMP after the Main Toolbox The appearance of the Layers dialog is shown in the adjoining illustration How it works is described in detail in the
108. present but impair the quality of the image such as a telephone wire running across the edge of a beautiful mountain landscape Despeckling A good tool for removing dust and other types of lens grunge is the Despeckle filter accessed as Filters gt Enhance gt Despeckle from the image menu Very important to use this filter effectively you must begin by making a small selection containing the artifact and a small area around it The selection must be small enough so that the artifact pixels are Statistically distinguishable from the other pixels inside the selection If you try to run despeckle on the whole image you will hardly ever get anything useful Once you have created a reasonable selection activate Despeckle and watch the preview as you adjust the parameters If you are lucky you will be able to find a setting that removes the junk while minimally affecting the area around it The more the junk stands out from the area around it the better your results are likely to be If it isn t working for you it might be worthwhile to cancel the filter create a different selection and then try again If you have more than one artifact in the image it is necessary to use Despeckle on each individually Garbage Removal The most useful method for removing unwanted clutter from an image is the Clone tool which allows you to paint over one part of an image using pixel data taken from another part or even from a different image The tri
109. some noise in the image A larger bright area will dilate by one pixel in all directions On more complex images bright areas are widened and enhanced the same and somewhat pixellated Options This filter has no option pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 338 of 421 Generated by docbook2odf Glass Effects filters Glass Effects filters introduction Glass Effects filters result in an image as if it were seen through a lens or glass tiles Apply Lens Parameter Settings Set Surroundings to Background Color O Make Surroundings Transparent Lens Refraction Index 1 70 B Overview 5 O N x O O 2 S O pe a 2 1 G 3 S o o GNU Image Manipulation Program Page 339 of 421 Generated by docbook2odf m m T j i oz TI reg Th k ia oie DAR any i You can find this filter via the image menu under Filters Glass effects Apply Lens After applying this filter a part of the image is rendered as through a spherical lens Options X Preview Keep original surroundings O Set surroundings to background color Lens refraction index 1 70 o Glass Tile Parameter Settings Tile Width Po aaa 20 Tile Height J 20 a Cancel o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 340 of 421 Generated by docbook2odf Overview iu qo e r
110. star reminding a Super nova It works with RGB and GRAY images Light effect decreases according to 1 r where r is the distance from star center Dieses Filter erzeugt einen grossen Stern im Bild der an eine Supernova erinnert Sie k nnen das Filter sowohl auf Farb als auch auf Graustufenbilder anwenden Parameter Settings GNU Image Manipulation Program Page 346 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o X Preview Center of SuperNova 128 128 x Show cursor Color aa Radius _ 20 Spokes ho E Random hue m Distort filters Distort filters introduction The distort filters transform your image in many different ways Blinds Background C Transparent Parameter Settings Displacement it 30 B Z Num Segments 1 Jo 3 B e x mesi Pox 2 xe P Overview This filter is found in Image gt Filters Distorts Blinds bs lt generates a blind effect with horizontal or vertical battens You can lift or close these i battens but not lift the whole blind up K 0 Oo GNU Image Manipulation Program Page 347 of 421 Generated by docbook2odf Options Example Curve Bend Preview Modify Curves Smooth Options Li Free Rotate o o B AE Copy Mirror Swap sJ Reset f Antialiasing Work on Copy B Open Save Cancel aP oK Overview This filter is found
111. the Ellipse Select tool are described here Ei can access to the Ellipse Selection options by double clicking on the icon Free Selection Tool Lasso GNU Image Manipulation Program Page 109 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o The Free Selection tool or Lasso lets you create a selection by drawing it free hand with the pointer while holding down the left mouse button or for a stylus pressing it against the tablet When you release the mouse button the selection is closed by connecting the current pointer location to the start location with a straight line You can go outside the edge of the image display and come back in if you want to The Lasso is often a good tool to use for roughing in a selection it is not so good for precise definition Experienced users find that it is often convenient to begin with the lasso tool but then switch to QuickMask mode for detail work For information on selections and how they are used in GIMP see Selections For Information on features common to all selection tools see Selection Tools The Free Selection tool is much easier to use with a tablet than with a mouse How to Activate he Lasso Tool can be activated from an image menu as Tools Selection Tools Free __ Select from the Toolbox by clicking on the tool icon or from the keyboard using the Shortcut f Key modifiers The Free Select tool does not ha
112. the active layer is already at the bottom of the stack or if there is only one layer this menu entry is insensitive and grayed out Activating the Command e You can access this command from the image menubar through Layer Stack Layer to Bottom e or by pressing the Shift key and clicking on the down arrow icon at the bottom of the Layers dialog The Colors Submenu Color Balance fs Hue Saturation amp Colorize Brightness Contrast Threshold uk Levels Curves Posterze p Des aturate P Inwert Auto Histogram Colorcube Analysis The Colors submenu contains operations which alter colors within the active layer The operations at the top of the list access the Color tools for the image These are described In the Toolbox chapter This command operates only on the layer which is active at the time the command is called Even after you make another layer the active layer the operation continues to affect the layer on which you performed the command Activating the submenu e You can access this submenu from the image menubar through Layer Colors Contents of the Colors Submenu In addition to the menu items relating to the color tools which are at the top of the list the Colors submenu contains the following menu items Desaturate GNU Image Manipulation Program Page 264 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3
113. the camera the iris of the eye can bounce the light of the flash back toward the camera in such a way as to make the eye appear bright red this effect is called red eye and looks very bizarre Many modern cameras have special flash modes that minimize red eye but they only work if you use them and even then they don t always work perfectly Interestingly the same effect occurs with animals but the eyes may show up as other colors such as green GIMP does not include a special tool for removing red eye but it isn t all that hard to do Basically the idea is to zoom the area around the eye so that it is nice and large and easy to work with then make a selection of the red part of the eye and a bit of the area around it feather the selection so that you don t create sharp looking edges and finally desaturate the red channel inside the selection using one of the color tools Levels Curves or Hue Saturation It takes a little practice the first few times but once you have the technique mastered you should be able to quickly and easily create quite a natural looking eye color If you would like a more automated approach you can try downloading a recently created redeye plug in from the GIMP Plug in Registry We have not received any feedback so far about how well it works It comes in source code form so you will need to be able compile it in order to use it See Installing New Plug ins for information on how to do this Saving Your
114. the image this filter holds the channel with the maximal minimal intensity Options Retinex Overview This filter is found in the image window menu under Filters Colors Retinex Retinex improves visual rendering of an image when lighting conditions are not good While our eye can see colors correctly when light is low cameras and video cams can t manage this well The MSRCR MultiScale Retinex with Color Restoration algorithm which is at the root of the Retinex filter is inspired by the eye biological mecanisms to adapt itself to these conditions Retinex stands for Retina cortex Besides digital photography Retinex algorithm is used to make the information tn astronomical photos visible and detect in medicine poorly visible structures in X rays or scanners Options GNU Image Manipulation Program Page 316 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 v o ww in o c o X Preview Level Uniform O Low O High Scale Scale division Dynamic These options call for notions that only mathematicians can understand In actual practice user has to grope about for the best setting pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 317 of 421 Generated by docbook2odf Semi Flatten Overview This filter is found in the image menu through Filters Colors Semi Flatten It is available
115. they aren t quite right When everything is perfect hit the Crop button in the dialog Improving Colors Automated Tools In spite of sophisticated exposure control systems pictures taken with digital cameras often come out over or under exposed or with color casts due to imperfections in lighting GIMP gives you a variety of tools to correct colors in an image ranging to automated tools that run with a simple button click to highly sophisticated tools that give you many parameters of control We will start with the simplest first GIMP gives you five automated color correction tools Unfortunately they don t usually give you quite the results you are looking for but they only take a moment to try out and if nothing else they often give you an idea of some of the possibilities inherent in the image Except for Auto Levels you can find them in the Layer menu by following the menu path Layer Colors Auto in the image menu Here they are with a few words about each Those are the automated color adjustments if you find that none of them quite does the job for you it is time to try one of the interactive color tools All of these except one can be accessed via Tools gt Color Tools in the image menu After you select a color tool click on the image anywhere to activate it and bring up its dialog Exposure Problems The simplest tool to use is the Brightness Contrast tool It is also the least powerful but in many cases it does
116. this tool has been installed in it You can do that through the Tool dialog Options Background 2 Untitled 4 Apply Threshold E E Threshold Range 127 255 Preview FJ Reset M Cancel Pox Using Threshold and Quick Mask to create a selection mask That s not always the case but an element you want to extract from an image can stand GNU Image Manipulation Program Page 141 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn o S o out well against the background In this case you can use the Threshold tool to select this element as a whole Grokking the GIMP described a method based on a channel mask but now using the Quick mask Is easier First start decomposing you image into its RGB and HSV components by using the Decompose filter A new grey scaled image is created and the components are displayed as layers in the Layer Dialog These layers come with a thumbnail but it is too small for an easy study You can of course increase the size of this preview with the dialog menu the Small triangular button but playing with the eyes is more simple to display the wanted layer in the decompose image Select the layer that isolates the element the best Layers Mode Normal Call the Threshold tool from the decompose image By moving the black cursor fit threshold to isolate the best the element you want to extract This will probably not be
117. too strong it will amplify noise in the image and also give rise to visible artifacts where there are sharp edges Sometimes using Unsharp Mask can cause color distortion where there are strong contrasts in an image When this happens you can often get better results by decomposing the image into separate Hue Saturation Value HSV layers and running Unsharp Mask on the Value layer only then recomposing This works because the human eye has much finer resolution for brightness than for color See the sections on Decompose and Compose for more information Next to Unsharp Mask in the Filters menu is another filter called Sharpen which does similar things It is a little easier to use but not nearly as effective our recommendation is that you ignore it and go straight to Unsharp Mask In some situations you may be able to get useful results by selectively sharpening specific parts of an image using the Blur or Sharpen tool from the Toolbox in Sharpen mode This allows you to increase the sharpness in areas by painting over them with any paintbrush You should be restrained about this though or the results will not look very natural sharpening increases the apparent sharpness of edges in the image but also amplifies noise Reducing Graininess When you take pictures in low light conditions or with a very fast exposure time the camera does not get enough data to make good estimates of the true color at each pixel and consequently th
118. variable may also refer to a list of values rather than a single value To assign the variable x the list of values 1 3 5 we d type BRRRRRER let B x 13H55 mx LTT TTT Try typing both statements into the Script Fu Console and notice how it replies When you type the first statement in it simply replies with the result BERRRREES BREE However when you type in the other statement it replies with the following result BR RRRREE LSE BREE When it replies with the value 8 it is informing you that x contains the atomic value 8 However when it replies with 1 3 5 it is then informing you that x contains not a single value but a list of values Notice that there are no commas in our declaration or assignment of the list nor in the printed result The syntax to define a list Is BERRRREER abblc BREE where a b and c are literals We use the apostrophe to indicate that what follows in the parentheses Is a list of literal values rather than a function or expression An empty list can be defined as such BRRRRREE BREE or simply BERR RREE BREE Lists can contain atomic values as well as other lists f BERRRREE lL et GNU Image Manipulation Program Page 87 of 421 Generated by docbook2odf xe e N E O O 2 0 O xo a 2 xe o 4 hn S o BERR REE ETT TTT x SERRE CO ThebGimp 8 LE2ES E is E great H H H H LTT TTT LETT TTT TTT T
119. which surrounds a selection ee i he line is animated so it looks as if little ants are running around behind each other ou can disable the marching ants by unchecking the View Show Selection option or by using the CtrIT key combination GIMP offers 21 layer modes The layer mode is used on the layers that are under the selected layer If there is only one layer the layer mode has no effect It is therefore highly likely that at least two layers are required The example images show the effects of each of the modes The left image is the normal state and the right image shows the results of the layer mode Masks are special elements associated with a layer or a selection They modify the transparency of the layer or selection They belong to two types e Layer Mask Every layer can have its own mask The layer mask represents the Alpha channel of the layer and allows you to manage the transparency of the layer By painting on the layer mask you can make some parts of the layer opaque or transparent painting with black makes the layer transparent and painting with white makes the layer opaque You can use all of the tools to paint on the mask You can use the Layer mask for transition effects volume effects merging elements from another image etc See Layer Mask for more details e Channel Mask also called Selection Mask this mask represents the Alpha channel of the image By painting on it with white you remove the mask and
120. you learn it we hope that you will like it GNU Image Manipulation Program Page 14 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 hn 0 S o The following sections will walk you through the components of each of the windows Shown in the screenshot explaining what they are and how they work Once you have read them plus the section describing the basic structure of GIMP images you should have learned enough to use GIMP for a wide variety of basic image manipulations You can then look through the rest of the manual at your leisure or just experiment to learn the almost limitless number of more subtle and specialized things that are possible Have fun The Main Toolbox The Main Toolbox is the heart of the GIMP It is the only part of the application that you cannot duplicate or close Here is a quick tour of what you will find there In the Toolbox as in most parts of GIMP moving the mouse on top of something and letting it rest for a moment will usually bring up a tooltip message that may help you understand what the thing is or what you can do with it Also in many cases you can press the F1 key to get help about the thing that is underneath the mouse Toolbox Menu This menu is special it contains some commands that cannot be found in the menus that are attached to images Also some that can These include commands for setting preferences creating certain types of d
121. you like Note that you can only Redo an operation if the last action you did was an Undo If you perform any operation on the image after Undoing something then the former Redo steps are lost and there is no way to recover them See the Undoing section for more information To see the operations which you have done and undone use the Undo History dialog Activating the Command e You can access this command from the image menubar through Edit Redo e by using the keyboard shortcut Ctrl Y e or by simply clicking on the status you want in the Undo History dialog Undo History The Undo History command activates the Undo History dialog which shows you thumbnails representing the operations you have done so far on the current image This overview makes it easier for you to undo steps or to redo them Use the arrows for Undo and Redo or simply click on the thumbnail to bring the image back to a previous state This is especially useful when you are working on a difficult task where you often need to undo several steps at once It is much easier to click on step 10 than to type Ctrl Z ten times The Clear undo History command may be useful if you are working on a complex image and you want to free some memory Activating the Command e You can access this command from the image menubar through Edit Undo History There is no default keyboard shortcut Cut The Cut command deletes the contents of the image s selections and sa
122. you ll have to enter an entire expression on one line that is everything between the opening and closing parens of an expression must come on one line in the Script Fu Console window Assigning A New Value To A Variable Once you ve initialized a variable you might need to change its value later on in the script Use the set statement to change the variable s value theNuml0 8 8 set theNumll 8theNumil BERRRRRR lect i a E EEREEEEEChNEeNum BREE Try to guess what the above statement will do then go ahead and enter it in the Script Fu Console window The indicates that there is no line break Ignore it don t type it in your Script Fu console and don t hit Enter just continue with the next line Functions Now that you ve got the hang of variables let s get to work with some functions You declare a function with the following syntax BERRRREE define namelparam list expressions LTT TT where name is the name assigned to this function param list is a soace delimited list of parameter names and expressions is a series of expressions that the function executes when it s called For example BERBER definel AddXY inxXliny 8inxXWiny ff BREE Addxy is the function s name and inxX and iny are the variables This function takes its two parameters and adds them together If you ve programmed in other imperative languages like C C Java Pascal etc you might notice that a couple of thing
123. you look at the script later Your First Script Fu Script Do you not need to stop and catch your breath No Well then let s proceed with your fourth lesson your first Script Fu Script Creating A Text Box Script One of the most common operations perform in Gimp is creating a box with some text in it for a web page a logo or whatever However you never quite know how big to make the initial image when you start out You don t know how much space the text will fill with the font and font size you want The Script Fu Master and student will quickly realize that this problem can easily be solved and automated with Script Fu We will therefore create a script called Text Box which creates an image correctly sized to fit snugly around a line of text the user inputs We ll also let the user choose the font font size and text color Editing And Storing Your Scripts Up until now we ve been working in the Script Fu Console Now however we re going to Switch to editing script text files Where you place your scripts is a matter of preference if you have access to Gimp s default script directory you can place your scripts there However prefer keeping my personal scripts in my own script directory to keep them separate from the factory installed scripts In the gimp 2 2 directory that Gimp made off of your home directory you should find a directory called scripts Gimp will automatically look in your gimp 2 2 di
124. 2 8 o 3 gt 2 a o ww hn o c o You can find this filter in the image menu under Filters Blur Pixelise The Pixelize filter renders the image using large color blocks It is very similar to the effect seen on television when obscuring a criminal during trial It is used for the Abraham Lincoln effect see Options Parameter Settings Pixel Width Lo Pixel Height 10 B Tileable Blur Overview e i i state nL TT i tt ono px GNU Image Manipulation Program Generated by docbook2odf Page 295 of 421 o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o You can find this filter in the image menu under Filters Blur Tileable Blur This tool is used to soften tile seams In images used in tiled backgrounds It does this by blending and blurring the boundary between images that will be next to each other after tiling If you want to treat only images borders you can t apply filter to the whole image The solution to get the wanted effect is as follows Duplicate layer Layer Duplicate Layer and select it to work on it Apply Tileable Blur filter with a 20 pixels radius to this layer Select all CtrlA and reduce selection Selection Shrink to create a border with the wanted width Delete selection with CtrlK Merge layers with Layer Merge down Options Script Arguments Radius a 5 ff Blur Vertically f Blur Hor
125. BAT extension Create shortcut and drag it to your desktop Start Programs Accessories System Tools System Informations Tools System Configuration Utility Environment tab New button Enter LANG for Name and fr or de for Value Under Window 95 and Windows 98 add the line set lang fr in the C autoexec bat file Go to System Preferences click on the International icon and in the Language tab the GNU Image Manipulation Program Page 8 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o desired language should be the first in the list pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 9 of 421 Generated by docbook2odf Starting GIMP the first time The first time you run GIMP it goes through a series of steps to set up options and directories This process creates a subdirectory of your home directory called gimp 2 2 All of the information about the choices you make here goes into that directory If you later remove that directory or rename it as something like gimp 2 2 bak then the next time you start GIMP it will go through the whole setup sequence again creating a new gimp 2 2 directory You can exploit this if you want to explore the effect of different choices without destroying your existing installation or if you have screwed things up so badly that your existing installation needs to be nu
126. COLORSHEEEEE Color SHRHHHEE ORORO ERRER colorlvariable BERR RRR SE ADJUSTMENTHE Bufferfamount SSHOH1LOOH1H10H180 eee aslider TT TTT EEEREN Script fu menu registerE script fu text box lt Toolbox gt Xtns Script Fu Text PTT TT PTT Adding The New Code We re going to add code in two places right before we resize the image and at the end of the script to return the new image the layer and the text Gn ao e N x e e 2 0 e a 2 ao eo w 9 S 9 GNU Image Manipulation Program Page 97 of 421 Generated by docbook2odf After we get the text s height and width we need to resize these values based on the buffer amount specified by the user We won t do any error checking to make Sure it s in the range of 0 100 because it s not life threatening and because there s no reason why the user can t enter a value like 200 as the percent of buffer to add BRBRRBEE set BtheBufferl 8theImageHeightl BinBufferAmount 100 Wf fl BRRRRRRE Set BthelmageHeight theImageHeight amp theBufferitheBuffer fl BERRRREE set BthelmagewidthWel B8thelImagewidthistheButferitheBuffer ll EERREE All we re doing here is setting the buffer based on the height of the text and adding it twice to both the height and width of our new image We add it twice to both dimensions because the buffer needs to be added to both sides of the text Now that we have resized the image t
127. Command e You can access this command from the tmage menubar through View Show Menubar Show Rulers The Show Rulers command enables and disables displaying the rulers It may be useful to disable them if you are working in full screen mode You can set the default for the rulers in the Image Window Appearance dialog Activating the Command e You can access this command from the image menubar through View Show Rulers e or by using the keyboard shortcut Shift Ctrl R Show Scrollbars The Show Scrollbars command enables and disables displaying the scrollbars It may be useful to disable them if you are working in full screen mode You can set the default for the scrollbars in the Image Window Appearance dialog Activating the Command e You can access this command from the image menubar through View Show Scrollbars Show Statusbar The Show Statusbar command enables and disables displaying the status bar It may be useful to disable it when you are working in full screen mode You can set the default for the status bar in the Image Window Appearance dialog GNU Image Manipulation Program Page 244 of 421 Generated by docbook2odf y xe O N E O O 2 S O xe a 2 xe o d 3 S o Activating the Command e You can access this command from the image menubar through View Show Statusbar pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Pa
128. E Z Incremental M Use color from gradient Gradient Reverse Length 100 g px Repeat Triangular wave Ra See the Brush Tools Overview for a description of tool options that apply to many or all brush tools pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o GNU Image Manipulation Program Page 121 of 421 Generated by docbook2odf Eraser The Eraser is used to remove areas of color from the current layer or from a selection of this layer If the Eraser is used on something that does not support transparency a selection mask channel a layer mask or the Background layer if it lacks an alpha channel then erasing will show the background color as displayed in the Color Area of the Toolbox in case of a mask the selection will be modified Otherwise erasing will produce either partial or full transparency depending on the settings for the tool options If you need to erase some group of pixels completely leaving no trace behind of their previous contents you should check the Hard edge box in the Tool Options Otherwise sub pixel brush placement will cause partial erasure at the edges of the brush stroke even if you use a hard edged brush If you use GIMP with a tablet you may find it convenient to treat the reverse end of the stylus as an eraser To make this work all you need to do is click the reverse end on the Eraser tool in the Toolbox Because each end of the stylus is trea
129. E eee OF ontSizeMPIXELS See Sans LET BRRRREEE EE BREE Although a long function call it s fairly straightforward if you go over the parameters while looking at the function s entry in the DB Browser Basically we re creating a new text layer and assigning it to the variable theText Now that we have the text we can grab its width and height and resize the image and the image s layer to the text s size BERRRREE set BthelmagewWwidthOae carl gimp drawable widthilltheText W ii BERRRREE set BthelmageHeightM carl gimp drawable height amp theText ll i BERRRREE gimp image resizelitheImagelitheImagewidthitheImageHeight OHO BRRRRREE gimp layer resizelitheLayerlitheImagewidthitheImageHeight OHO EEEEEE If you re like me you re probably wondering what a drawable is when compared to a layer The difference between the two is that a drawable is anything that can be drawn into including layers but also channels layer masks the selection etc a layer is a more specific version of a drawable In most cases the distinction is not important With the image ready to go we can now re add our display line EEEEEEEE gimp display newlltheImage PTT Save your work refresh the database and give your first script a run GNU Image Manipulation Program Page 95 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o hn S o Clearing The Dirty Flag If y
130. It s a good way to isolate asubject in a picture because once the selection is made you only have to remove its content or inverse if the subject is in the selection Using Quick Mask s Screenshot of the image window with activated QuickMask The QuickMask is filled with a gradient from black left to white right The QuickMask is now disabled and a selection is initialised from the QuickMask which was filled by a gradient before You see the selection borders in the middle of the image A stroke is now added during the enabled selection The key is that the black color will have no opacity of the resulting stroke right and white color will have a full opacity of the stroke left After the QuickMask Button is pressed the command generates a temporary 8 bit 0 255 channel on which the progressive selection work is stored If a selection is already present the mask Is initialized with the content of the selection Once QuickMask has been activated the image is covered by a red semi transparent veil This one representes the non selected pixels Any paint tool can be used to create the selection on the QuickMask They should use only greyscale color conforming the channel properties white enabling to define the future selected place The selection will be displayed as soon as the QuickMask will be toggled but its temporary channel will not be available anymore To save in a channel the selection done with the Quickmask select in th
131. Landscape orientation They work on the whole image If you want to rotate the image at a different angle rotate a selection or rotate a layer use the Rotate Tool You can also rotate a layer by using the Layer Transform menu GNU Image Manipulation Program Page 249 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Activating the Commands You can access these three commands from the image menubar through e Image Transform Rotate 90 degrees CW e Image Transform Rotate 90 degrees CCW and e Image Transform Rotate 180 Guillotine The Guillotine command slices up the current image based on the image s guides It cuts the image along each guide similar to slicing documents in an office with a guillotine paper cutter and creates new images out of the pieces For further information on guides see the glossary entry for Guides Activating the Command e You can access this command from the image menubar through Image Transform Guillotine Canvas Size The canvas is the visible area of the image By default the size of the canvas coincides with the size of the layers The Canvas Size command lets you enlarge or reduce the Canvas size without modifying the contents of the layers in the image When you enlarge the canvas you create free space around the contents of the image When you reduce it the visible area is cropped however the layers still extend beyond the ca
132. NU Image Manipulation Program Page 420 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o with the Invariant Sections being LIST THEIR TITLES with the Front Cover Texts being LIST and with the Back Cover Texts being LIST If you have Invariant Sections without Cover Texts or some other combination of the three merge those two alternatives to suitthe situation lf your document contains nontrivial examples of program code we recommend releasing these examples in parallel under your choice of free software license such as the GNU General Public License to permit their use in free software Sorry but a help item is missing for the function you re looking for Feel free to join us and fill the gap by writing documentation for the Gimp For more information visit our project page on the Gimp Wiki There is also a Mailing list available Generally it s a good idea to check the Gimp project page GNU Image Manipulation Program Page 421 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o
133. O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 101 of 421 Generated by docbook2odf Creating a brush with variable size You can create a brush with a size which will vary by rotating the mouse wheel or by using the keyboard arrow keys 1 Start with opening the Brush dialog by double clicking on the Brush area in Toolbox or by going through File Dialogs Brushes 2 Click on the New Brush button to open the Brush Editor dialog Name your brush at once Dynamic for instance Your brush will appear in the Brush Dialog with a blue corner e Check the Enable this controller box e Scroll through the Events list and select Scroll up Shift Avoid Scroll up Ctrl because Ctrl is yet used by tools to turn to the Color Picker mode e Click on the Edit button to open a window that allows you to assign an action to the selected event If an action is assigned to the event yet the window opens on this event else click on the small triangular button close to the Context item to drop the list down Scroll through this list and select the context brush radius Increase item You could choose context brush radius increase skip Click on OK e Do the same way to assign the context brush radius decrease action to the Scroll down Shift event to decrease the brush size 3 Save your brush by clicking on the Save button in the Brush Editor Now if you have selected your Dynamic brush when y
134. O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 147 of 421 Generated by docbook2odf The Color Picker Tool is used to select a color on the active layer By clicking a point ona layer you can change the active color to that which is located under the pointer The Sample Merge option lets you grab the color as it is in the image resulting of the combination of all layers Activate Tool e The Color Picker Tool can be called in the following order from the image menu Tools Color Picker e The Tool can also be called by clicking the tool icon If you hold Ctrl key down while using a paint tool mouse pointer turns to the color picker icon If you click then you select the color pointed by the color picker as foreground color Color picker dialog is not opened during this operation Key modifiers Defaults Options Color Picker Sample average Sample merged Pick Mode lt Ctrl gt L Pick only Set foreground color O Set background color Add to palette lt Shift gt Magnify Tool The Magnify Tool is used to change the zoom level of your working image If you only click on the image the zoom is applied to the whole image But you can also click and drag the mouse pointer to create a zoom rectangle Then the action of this rectangle is better GNU Image Manipulation Program Page 148 of 421 Generated by docbook2odf pe O N E O O 2 S
135. OOH1H10H0H1 eee aBspin button BERGER SE COLORSHEEEEE Color SERHHEEE ORORO MHEEE colorlvariable LTT TTT BERRREEE Script fu menu registerE script fu text box E lt Toolbox gt Xtns Script Fu Text PTT TT PTT TT If you save these functions in a text file with a scm suffix in your script directory then GNU Image Manipulation Program Page 91 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o hn S o choose Xtns Script Fu Refresh Scripts this new script will appear as Xtns Script Fu Text Text Box If you invoke this new script it won t do anything of course but you can view the prompts you created when registering the script more information about what we did is covered next Finally if you invoke the Procedure Browser Xtns Procedure Browser you ll notice that our script now appears in the database Steps For Registering The Script To register our script with Gimp we call the function script fu register fill in the seven required parameters and add our script s own parameters along with a description and default value for each parameter The Required Parameters e The name of the function we defined This is the function called when our script is invoked the entry point into our script This is necessary because we may define additional functions within the same file and Gimp needs to know which of these functions to call In ou
136. Object filter You can also map a part of the image elsewhere into the same image Illusion and Make Seamless filters bend a text along a curve Displace filter Bump Map Overview This filter is found in the image window menu under Filters Map Bump Map This filter creates a 3D effect by embossing an image the card and then mapping it to another image Bump heigth depends on pixel luminosity and you can set light direction See Emboss for more informations about embossing You can bump map any type of image unlike the Emboss filter Options Bump map Untitled 1 Background 2 w Maptype Liner OOOO Ooy x Compensate for darkening invert bumpmap Tile bumpmap Azimuth _e 135 00 Elevation Depth X offset Y offset Waterlevel x Preview Ambient Displace pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 370 of 421 Generated by docbook2odf Preview xX X displacement 20 00 fe 2zinnias png 1 Background 2 P Lz png g x Ydisplacement 20 00 S 2zinnias png L Background 2 On Edges Wrap Smear C Black Overview You can find this filter from the image menu Filters M Displace This filter uses a displace map to displace corresponding pixels of the image This filter displaces the content of the specified drawable active layer or selection by the amounts Specified in X and Y Displacement multiplied
137. Parameter Settings Random Seed fo Randomize Randomization fb 50 Overview This filter is found in Filters Noise Pick The Pick filter replaces each affected pixel by a pixel value randomly chosen from its eight neighbours and itself from a 3X3 square the pixel is center of All or only some pixels in an active layer or selection are affected the percentage of affected pixels is determined by the Randomization option Options Scatter HSV GNU Image Manipulation Program Page 322 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Preview 1 4 Right Click to Jump Parameter Settings Saturation _ J 7 10 Value J 10 Overview This filter is found in Image gt Filters Noise Scatter HSV The Scatter HSV filter creates noise in the active layer or selection by using the Hue Saturation Value luminosity color model Options Slur Parameter Settings Random Seed Eo l Randomize Randomization SSO Repeat C fo l B Homea Pax Overview This filter is found in Filters Noise Slur Slurring produces an effect resembling melting the image downwards If a pixel is to be Slurred there is an 80 chance that it is replaced by the value of a pixel directly above it otherwise one of the two pixels to the left or right of the one above is used All or only some pixels in an active layer or selection are affected the percentage of
138. Patterns section for basic information on patterns and how they can be created and used You can use them with Bucket Fill et Clone tools and the Fill with pattern command pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 169 of 421 Generated by docbook2odf The Patterns dialog is used to select a pattern by clicking on it in a list or grid view the selected pattern will then be shown in the Brush Pattern Gradient area of the Toolbox A few dozen more or less randomly chosen patterns are supplied with GIMP and you can easily add new patterns of your own Activate Dialog The Patterns dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in several ways e From the Toolbox menu File Dialogs Patterns e From the Toolbox menu File Dialogs Create New Dock Brushes Patterns and Gradients This gives you a dock containing three dialogs with the Patterns dialog one of them e From the Toolbox by clicking on the pattern symbol in the Brush Pattern Gradient area e From an image menu Dialogs Patterns e From the Tab menu in any dockable dialog Add Tab Patterns e From the Tool Options dialog for the Clone tool by clicking on the Pattern icon button This option appears because the Clone tool is capable of painting with patterns Using the pattern dialog Gradients dialog FG to BG HSV clockwise
139. RGB to grayscale or indexed for example lose information that cannot be regained by converting back in the other direction If you are trying to use a filter on an image and it appears grayed out in the menu usually the cause is that the image or more specifically the layer you are working on is the wrong type Many filters can t be used on indexed images Some can be used only on RGB images or only on grayscale images Some also require the presence or absence of GNU Image Manipulation Program Page 23 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o an alpha channel Usually the fix is to convert the image to a different type most commonly RGB QuickMask The selection tools sometimes show their limits when they have to be used for creating a complex selection In these cases using the QuickMask can make things much easier Simply put the QuickMask allows you to paint a selection instead of just tracing its outline Overview Normally when you create a selection in GIMP you see it represented by the marching ants that trace along its outline But really there may be a lot more to a selection than the marching ants show you in GIMP a selection is actually a full fledged grayscale channel covering the image with pixel values ranging from O unselected to 255 fully selected The marching ants are drawn along a contour of half selected pixels Thus wh
140. Refresh button in the Fonts dialog Windows The easiest way to install a font is to drag the file onto the Fonts directory and let the Shell do its magic Unless you ve done something creative it s probably in its default location of C windows fonts Or C winnt fonts Sometimes double clicking on a font will install it as well as display it sometimes it only displays it This method will make the font available not only to GIMP but also to other Windows applications To install a Type 1 file you need both the pfb and pfm files Drag the one that gets an icon into the fonts folder The other one doesn t strictly need to be in the same directory when you drag the file since it uses some kind of search algorithm to find it if it s not but in any case putting it in the same directory does no harm In principle GIMP can use any type of font on Windows that FreeType can handle however for fonts that Windows can t handle natively you should install them by placing the font files in the fonts folder of your personal GIMP directory or some other location in your font search path The support Windows has varies by version All that GIMP runs on support at least TrueType Windows FON and Windows FNT Windows 2000 and later Support Type 1 and OpenType Windows ME supports OpenType and possibly Type 1 but the most widely used Windows GIMP installer does not officially support Windows ME although it may work anyway GIMP uses Fontconfig to ma
141. Results Files What file format should you use to save the results of your work and should you resize it The answers depend on what you intend to use the image for e f you intend to open the image in GIMP again for further work you should save it in GIMP s native XCF format i e name it something xcf because this is the only format that guarantees that none of the information in the image is lost e f you intend to print the image on paper you should avoid shrinking the image except by cropping it The reason is that printers are capable of achieving much higher dot resolutions than video monitors 600 to 1400 dots per inch for typical printers as compared to 72 to 100 dots per inch for monitors A 3000 x 5000 image looks huge on a monitor but it only comes to about 5 inches by 8 inches on paper at 600 dpi There is usually no good reason to expand the image either you can t increase the true resolution that way and it can always be scaled up at the time it is printed As for the file format it will usually be fine to use JPEG at a quality level of 75 to 85 In rare cases where there are large swaths of nearly uniform color you may need to set the quality level even higher or use a lossless format such as TIFF instead e f you intend to display the image on screen or project it with a video projector bear in mind that the highest screen resolution for most commonly available systems is 1600 x 1200 so there is nothing to gai
142. Stretch Contrast This command is somewhat similar to Normalize plug in in its effects except that it works on each color channel of the layer individually rather than just the brightness values This usually leads to color shifts within the tmage so it may not produce the result you are looking for Stretch Contrast operates on layers from RGB Grayscale and Indexed Images Activate Dialog e This command can be accessed from an image menubar as Layer Color Auto Stretch Contrast Color Enhance Color Enhance increases the saturation range of colors in the layer without altering brightness or hue It does this by converting the colors in HSV space measuring the range of saturation values across the image then stretching this range to be as large as possible and finally converting the colors back to RGB It works on layers from RGB and GNU Image Manipulation Program Page 267 of 421 Generated by docbook2odf xe O N E O O 2 S O S a 2 xe o d 3 S o Indexed images If the image Is Grayscale the menu entry will be insensitive Activate Dialog e This command can be accessed from an image menubar as Layer Color Auto Color Enhance Stretch HSV This command does the same thing as Stretch Contrast except that it works in HSV color Space rather than RGB color space Thus it independently stretches the hue channel the saturation channel and the value channel Occasionally the results are g
143. TT TT Tt bse BE RRRREEE BREE Notice that after the first apostrophe you no longer need to use an apostrophe when defining the inner lists Go ahead and copy the statement into the Script Fu Console and see what it returns You should notice that the result returned is not a list of single atomic values rather it is a list of a literal The Gimp the list 1 2 3 etc How To Think Of Lists It s useful to think of lists as composed of a head and a tail The head is the first element of the list the tail the rest of the list You ll see why this is important when we discuss how to add to lists and how to access elements in the list Creating Lists Through Concatenation The Cons Function One of the more common functions you ll encounter is the cons function It takes a value and prepends it to its second argument a list From the previous section suggested that you think of a list as being composed of an element the head and the remainder of the list the tail This is exactly how cons functions it adds an element to the head of a list Thus you could create a list as follows BRRRRREE consH1l 203584 f BREE The result is the list 1 2 3 4 You could also create a list with one element BERRRREE consHli amp BREE You can use previously declared variables in place of any literals as you would expect Defining A List Using The list Function To define a list composed of literals or previously dec
144. The Cut Named command cuts the contents of the selection from the active layer in the usual way but instead of storing the contents in the global clipboard it stores it ina special buffer that you name using a pop up dialog Activating the Command e You can access this command from the image menubar through Edit Buffer Cut e or by using the keyboard shortcut Shift Ctrl X Copy Named The Copy Named command copies the contents of the selection from the active layer in the usual way but instead of storing the contents in the global clipboard it stores it ina special buffer that you name using a pop up dialog Activating the Command e You can access this command from the image menubar through Edit Buffer Copy e or by using the keyboard shortcut Shift Ctrl C Paste Named The Paste Named command simply brings up the Buffers dialog By selecting one of the listed buffers and pressing one of the buttons at the bottom you can either Paste Buffer Paste Buffer Into or Paste Buffer as New Activating the Command e You can access this command from the image menubar through Edit Buffer Paste e or by using the keyboard shortcut Shift Ctrl V Clear The Clear command deletes everything in the current selection If there is no current GNU Image Manipulation Program Page 225 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o selection the contents of the active layer
145. The following list is a short overview of some of the features and capabilities which GIMP offers you e A full suite of painting tools including brushes a pencil an airbrush cloning etc e Tile based memory management so image size Is limited only by available disk Space e Sub pixel sampling for all paint tools for high quality anti aliasing e Full Aloha channel support for working with transparency e Layers and channels e A procedural database for calling internal GIMP functions from external programs such as Script Fu e Advanced scripting capabilities e Multiple undo redo limited only by disk space e Transformation tools including rotate scale shear and flip e File formats supported include GIF JPEG PNG XPM TIFF TGA MPEG PS PDF PCX GNU Image Manipulation Program Page 4 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o BMP and many others e Selection tools including rectangle ellipse free fuzzy bezier and intelligent e Plug ins that allow for the easy addition of new file formats and new effect filters pe O N E O O 2 S O xe a 2 xe o 4 G d 0 S o GNU Image Manipulation Program Page 5 of 421 Generated by docbook2odf What s New in The GIMP GIMP 1 0 evolved gradually into the very stable and widely used 1 2 release Three years later as the GIMP development came closer to the next stable release they deci
146. This is also a good tool for creating displacement maps for the plug in or for the plug in With the turbulence setting active the results look quite a bit like real clouds An example is shown below Options Flame pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 383 of 421 Generated by docbook2odf Rendering Camera Brightness Contrast Gamma Sample Density Spatial Qversample Spatial Filter Radius Colormap Custom Gradient lt Cancel oP ox Overview pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 384 of 421 Generated by docbook2odf This filter is found in Filters Render Nature Flame With the Flame filter you can create stunning randomly generated fractal patterns You can t control the fractals as you can with the Ifs Compose filter but you can steer the random generator in a certain direction and choose from variations of a theme you like In the main window you can set Rendering and Camera parameters The first three parameters in the Render display are Brightness Contrast and Gamma The result of these options is visible in the Preview window but it s generally better to stick to the default values and correc
147. XML data files e A completely revamped File Chooser is used everywhere in the GIMP for opening or saving files The best thing about it is that it lets you create a set of bookmarks making it possible to navigate quickly and easily to commonly used directories e GIMP now Supports fancy ARGB cursors when they are available on the system Basic vector support Using the GFig plug in the GIMP now supports the basic functionality of vector layers The GFig plug in supports a number of vector graphics features such as gradient fills Bezier curves and curve stroking It is also the easiest way to create regular or irregular polygons in the GIMP In the GIMP 2 2 you can create GFig layers and re edit these layers in GFig afterwards This level of vector support is still quite primitive however in comparison to dedicated vector graphics programs such as Inkscape Also There are many other smaller user visible features A rapid fire list of some of those features Is below e It is now possible to run the GIMP in batch mode without an X server e We have a GIMP binary GIMP console which is not linked to GTK at all e Improved interface for extended input devices e Editable toolbox You can now decide which tools should be shown in the Toolbox and their order In particular you can add any or all of the Color Tools to the Toolbox if you wish to e Histogram overlays R G and B histograms on the Value histogram and calculates th
148. a function Mapping input brightness levels to output brightness levels The Curves tool can replicate any effect you can achieve with Brightness Contrast or the Levels tool so it is more powerful than either of them Once again we refer you to the Curves Tool Help for detailed instructions but the easiest way to learn how to use it is by experimenting The most powerful approach to adjusting brightness and contrast across an image for more expert GIMP users is to create a new layer above the one you are working on and then in the Layers dialog set the Mode for the upper layer to Multiply The new layer then serves as a gain control layer for the layer below it with white yielding maximum gain and black yielding a gain of zero Thus by painting on the new layer you can selectively adjust the gain for each area of the image giving you very fine control You Should try to paint only with smooth gradients because sudden changes in gain will give rise to spurious edges in the result Paint only using shades of gray not colors unless you want to produce color shifts in the image Actually Multiply is not the only mode that is useful for gain control In fact Multiply mode can only darken parts of an image never lighten them so it is only useful where some parts of an image are overexposed Using Divide mode has the opposite effect it can brighten areas of an image but not darken them Here is a trick that is often useful for bringin
149. age Manipulation Program Page 108 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Key modifiers See Selection Tools for help with modifier keys that affect all these tools in the same way Only effects that are specific to the Ellipse Select tool are explained here e Ctrl Pressing the Ctrl key after starting your selection and holding it down until you are finished causes your starting point to be used as the center of the selected ellipse instead of a corner of the rectangle that may contain it Note that if you press the Ctrl key before starting to make the selection the resulting selection will be subtracted from the existing selection e Shift Pressing the Shift key after starting your selection and holding it down until you are finished constrains the selection to be a circle Note that if you press the Shift key before starting to make the selection the resulting selection will be added to the existing selection e Ctrl Shift Pressing both keys combines the two effects giving you a circular selection centered on your starting point Options Ellipse Select Mode 2 Eh aly Z Antialiasing Feather edges Radius 10 0 Auto shrink selection 7 Sample merged Free select Width 293 2 Height 126 g px a a a al See Selection Tools for help with options that are common to all these tools Only options that are specific to
150. alogs with the Undo History dialog one of them From an image menu Edit Undo History From an image menu Dialogs Undo History From the Tab menu in any dockable dialog Add Tab Undo History Using the Undo History dialog The most basic thing you can do is to select a point in the Undo History by clicking on it in the list You can go back and forth between states in this way as much as you please without losing any information or consuming any resources In most cases the changes are very fast At the bottom of the dialog are three buttons GNU Image Manipulation Program Page 166 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Image content related dialogs Colors dialog FGfBG Color et gt ed s A a s a g The Channel dialog lets you manage and pick up new colors It is divided into five separate parts GIMP CMYK Triangle Watercolor and Scales You can use the eyedropper which is the last button of the dialog to pick up a color anywhere on your screen Activate Dialog The dialog can be called in the following ways e from the toolbox menu File Dialogs Colors e from the toolbox click on the current Foreground or Background color e from the image menu Dialogs Colors e from an other dialog menu Add Tab Colors Using the dialog Brushes dialog o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o GNU I
151. als exclusively with the relationship of the publishers or authors of the Document to the Document s overall subject or to related matters and contains nothing that could fall directly within that overall subject Thus if the Document is in part a textbook of mathematics a Secondary Section may not explain any mathematics The relationship could be a matter of historical connection with the subject or with related matters or of legal commercial philosophical ethical or political position regarding them The Invariant Sections are certain Secondary Sections whose titles are designated as being those of Invariant Sections in the notice that says that the Document Is released under this License If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant The Document may contain zero Invariant Sections If the Document does not identify any Invariant Sections then there are none The Cover Texts are certain short passages of text that are listed as Front Cover Texts or Back Cover Texts in the notice that says that the Document is released under this License A Front Cover Text may be at most 5 words and a Back Cover Text may be at most 25 words GNU Image Manipulation Program Page 416 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o A Transparent copy of the Document means a machine readable copy represented in a
152. ance Foreground Color Background Color o Pixels sJ Reset Cancel Pox In the Configure Image Grid dialog you can set the properties of the grid which is shown when you turn on the image grid pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 258 of 421 Generated by docbook2odf Layers Introduction to the Layer Menu New Layer di Duplicate Layer alls Anchor Layer gil Merge Down i Delete Layer Stack Colors Mask Transparency Transform a Crop Layer Autocrop Layer Align Layers Align Visible Layers The items on the Layer menu allow you to work on layers In addition to accessing the Layer menu from the Image menubar and by right clicking on the image window you can get to it by right clicking on the thumbnail of a layer in the Layers dialog You can also perform several of the operations on this menu by clicking on buttons in the Layers dialog for example resizing a layer managing layer transparency and merging layers This menu can contain other entries besides the ones described in this section They are not part of GIMP itself but are extensions plug ins Please refer to the documentation about the plug ins for more information New Layer The New Layer command adds a new empty layer to the layer stack of the image just above the active layer The command displays a dialog in which you can specify the size of t
153. anipulation Program Page 65 of 421 Generated by docbook2odf Paths Stroking a Path Paths do not alter the appearance of the image pixel data unless they are stroked using Edit Stroke Path from the image menu or the Paths dialog right click menu or the Stroke Path button in the Tool Options dialog for the Path tool ta Choose Stroke Style Unnamed 3 Untitled Stroke line Line Width Jeo px 7 Line Style Cap style m m in Join style as ie Miter limit m fzo g f Dash pattern 4 jumm gt Dash preset Custom jv Antialiasing Solid Pattern Stroke with a paint tool Paint Tool g Paintbrush O Help Reset cancel Gf stroke Choosing Stroke Path by any of these means brings up a dialog that allows you to control the way the stroking is done You can choose from a wide variety of line styles or GNU Image Manipulation Program Page 66 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o you can stroke with any of the Paint tools including unusual ones such as the Clone tool Smudge tool Eraser etc You can further increase the range of stroking effects by stroking a path multiple times or by using lines or brushes of different widths The possibilities for getting interesting effects in this way are almost unlimited Transforming Paths Each of the Transform tools Rotate Scale Perspective etc
154. ant to create a shortcut for in the Action area Then you type your key sequence as above In principle the Space bar GNU Image Manipulation Program Page 99 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Should clear a shortcut In practice it clears it but doesn t delete it This shortcut editor also allows you to control the tool parameter settings with the keyboard At the top of this dialog you can find a Context menu that takes you to the tool parameters To make your work easier tool types are marked with small icons Custom Keyboard shortcuts are stored in one of Gimp s hidden directory home username gimp 2 2 menurc under Linux and C Documents and Settings Username gimp 2 2 menurc under Windows XP It is a simple text file that you Can transport from one computer to another GNU Image Manipulation Program Page 100 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o The GIH dialog box Spacing percent 20 Description GIMP Brush Pipe Cell size 30 x 30 E Fixels Number of cells 1 z H Display as 1 Rows of 1 Columns on each layer Dimension Ranks random random random TI random OJ Help i This dialog box has several options not easy to understand They allow you to determine the way your brush is animated pe O N E O
155. any further input It uses image color intensities 0 255 mapping the darkest pixels to the left end color from the gradient and the lightest pixels to the right end color from the gradient Intermediate values are set to the corresponding intermediate colors Border Average Border Size Thickness 3 l Number of Colors Bucket Size 16 Overview This filter is found in Filters Colors Border Average This tool calculates the average color in a border around active layer or selection Calculated color becomes the foreground color in Toolbox This filter is interesting when you have to find a Web page color background that differs as less as possible from your image border The action of this filter is not registered in Undo History and can t be deleted with Ctrl Z Options Channel Mixer Overview GNU Image Manipulation Program Page 306 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o This filter is found in Filters Colors Channel Mixer This filter combines values of the RGB channels It works with images with or without an alpha channel It has monochrome mode and a preview Options X Preview Output channel ByRed lah Red el a jee 100 0 5 EF Green m 0 0 S Blue a 0 0 o Monochrome Preserve luminosity L5 Open al Save Buttons Colorcube Analysis o_ 3 o N x e o 2 8 o 3 gt 2 a o ww
156. ar The shape of the cursor changes when it is inside an image to one that indicates which tool is active Tool Options Rect Select lv Antialiasing Feather edges Radius Tea Auto shrink selection Sample merged Free select If you have things set up like most people do activating a tool causes its Tool Options dialog to appear below the Toolbox If you don t have things set up this way you probably GNU Image Manipulation Program Page 104 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Should it is very difficult to use tools effectively without being able to manipulate their options The Tool Options appear beneath the Toolbox in the default setup If you lose it somehow you can get it back by creating a new Tool Options dialog using File gt Dialogs gt Tool Options and then docking it below the Toolbox See the section on Dialogs and Docking if you need help Each tool has its own specific set of options The choices you make for them are kept throughout the session until you change them In fact the tool options are maintained from session to session The persistence of tool options across sessions can sometimes be an annoying nuisance a tool behaves very strangely and you can t figure out why until you remember that you were using some unusual option the last time you worked with it two weeks ago At the bottom of the Tool
157. ar through Layer Transform Offset e or by using the keyboard shortcut Shift Ctrl O Description of the Offset dialog Offset Layer Background copy 1 4 Untitled Offset by x 2 y 2 Edge Behaviour Wrap around O Fillwith background color Make transparent Layer Boundary Size In GIMP a layer is not always the same size as the image it belongs to It might be smaller or it might be larger in which case some parts of it are hidden The Layer Boundary Size command displays a dialog in which you can set the dimensions for the active layer This command changes the dimensions of the layer but it does not scale its contents Activating the Command GNU Image Manipulation Program Page 279 of 421 Generated by docbook2odf pe O N E O O 2 0 O S a 2 xe o 4 d 3 S o e You can access this command from the image menubar through Layer Layer Boundary Size Description of the Layer Boundary Size dialog ER i Set Layer Boundary Size tami Background 2 2zinnias png Layer Size Width Height 138 B 5 pixels l __1 ___ 200 x 136 pixels 72 dpi o Help Reset X Cancel Fl Resize Layer to Image Size The Layer to Image Size command resizes the layer boundaries to match the image boundaries without moving the contents of the layer with respect to the image Activating the Command e You can access this command from the image menuba
158. arge number can be found at the GIMP Plugin Registry a web site whose purpose Is to provide a central repository for plugins Creators of plugins can upload them there users in search of plugins for a specific purpose can search the site in a variety of ways Anybody in the world can write a GIMP plugin and make it available over the web either via the Registry or a personal web site and many very valuable plugins can be obtained in this way some are described elsewhere in the User s Manual With this freedom from constraint comes a certain degree of risk though the fact that anybody can do it means that there is no effective quality control The plugins distributed with GIMP have all been tested and tuned by the developers but many that you can download were just hacked together in a few hours and then tossed to the winds Some plugin creators just don t care about robustness and even for those who do their ability to test on a variety of systems in a variety of situations is often quite limited Basically when you download a plugin you are getting something for free and sometimes you get exactly what you pay for This is not said in an attempt to discourage you just to make sure you understand reality Plugins being full fledged executable programs can do any of the things that any other program can do including install back doors on your system or otherwise compromise its security Don t install a plugin unless it comes from a trusted
159. articular file type At Determine File Type you have to select the file format for saving the file If you select By Extension the file type is determined by the extension you add to the name for example jog for JPEG format To preserve all the components of your image when you save it the layers channels etc use xcf format which is the GIMP s native format Save a Copy The Save a Copy command does the same thing as the Save command but with one important difference It always asks for a file name and saves the image into the specified file but it does not change the name of the active image or mark it as clean As a result if you try to delete the image or exit from GIMP you are informed that the image is dirty and given an opportunity to save it This command is useful when you want to save a copy of your image in its current state but continue to work with the original file without interruption Activating the Dialog e You can access this command from the image menubar as File Save a Copy It does not have a default shortcut Save as Template The Save as Template command creates a template with the same dimensions and color Space as the current image A dialog pops up which asks you to name the new template then the template is saved and becomes available in the New Image dialog If you give a name that already exists GIMP generates a unique name by appending a number to it You can use the T
160. at the marching ants show you as either or inside or outside the boundary is really just a slice through a continuum The QuickMask is GIMP s way of showing you the full structure of the selection Activating it also gives you the ability to interact with the selection in new and substantially more powerful ways To activate the QuickMask click on the small red outlined button at the lower left of the image window The button is a toggle so clicking it again will return you to normal marching ant mode You can also activate the QuickMask by selecting in the image window menu Select Toggle QuickMask or by using the ShiftQ shortcut Activating the QuickMask shows you the selection as though it were a translucent screen overlying the image whose transparency at each pixel indicates the degree to which that pixel is selected By default the mask is shown in red but you can change this if another mask color would be more convenient The less a pixel is selected the more it is obscured by the mask Fully selected pixels are shown completely clear When you are in QuickMask mode many image manipulations act on the selection channel rather than the image itself This includes in particular paint tools Painting with white causes the painted pixels to be selected painting with black causes them to be unselected You can use any of the paint tools as well as the bucket fill and gradient fill tools in this way Advanced users of the GIMP learn that
161. aterial this License requires to appear in the title page For works in formats which do not have any title page as such Title Page means the text near the most prominent appearance of the work s title preceding the beginning of the body of the text A section Entitled XYZ means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language Here XYZ stands for a specific section name mentioned below such as Acknowledgements Dedications Endorsements or History To Preserve the Title of such a section when you modify the Document means that it remains a section Entitled XYZ according to this definition The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document These Warranty Disclaimers are considered to be included by reference in this License but only as regards disclaiming warranties any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License You may copy and distribute the Document in any medium either commercially or noncommercially provided that this License the copyright notices and the license notice saying this License applies to the Document are reproduced in all copies and that you add no other conditions whatsoever to those of this License You may not use technical measures to obstruct or control t
162. aussian blurs It is probably easiest to set them using the preview but it may help to know that increasing the smaller radius tends to give thicker appearing edges and decreasing the larger radius tends to increase the threshold for recognizing something as an edge In most cases you will get nicer results if Radius 2 is smaller than Radius 1 but nothing prevents you from reversing them and in situations where you have a light figure on the dark background reversing them may actually improve the result Options Edge C Prewitt Gradient Roberts Differential Laplace Parameter Settings Amount __ Ti 2 0 Wrap Smear Black GNU Image Manipulation Program Page 326 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Overview This filter is found in Image gt Filters Edge Detect Edge Options Laplace Overview This filter is found in Filtres Edge detect Laplace This filter detects edges in the image using Laplacian method which produces thin pixel wide borders Sobel Parameter Settings W Sobel Vertically W Keep Sign of Result one Direction only Overview This filter is found in Filters Edge detect Sobel Sobel s filter detects horizontal and vertical edges separately on a grey level image Color images are turned into grey levels Options GNU Image Manipulation Program Page 327 of 421 Generated by docbook2odf
163. ave selected in one of four ways Show Selection The Show Selection command enables and disables displaying the dotted line surrounding the selection in the image window Please note that the selection still exists even if displaying this line is disabled You can set the default for displaying the selection in the Image Window Appearance dialog Activating the Command e You can access this command from the image menubar through View Show Selection r e or by using the keyboard shortcut Ctrl T Show Layer Boundary The Show Layer Boundary command enables and disables displaying the yellow dotted line that surrounds a layer in the image window The dotted line is actually only visible when the layer is smaller than the image window When the layer is the same size as the image window the layer boundary is obscured by the image border You can set the default for the layer boundary in the Image Window Appearance dialog Activating the Command e You can access this command from the image menubar through View Show Layer Boundary Show Guides The Show Guides command enables and disables diplaying of Guides in the image window You can set the default for the guides in the Image Window Appearance dialog GNU Image Manipulation Program Page 242 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Activating the Command e You can access this command from the
164. away from the worst point to look for a better place to subdivide e Subdivide Surround Number of points to consider when deciding whether a given point is a better place to subdivide e Subdivide Threshold How many pixels a point can diverge from a straight line and still be considered a better place to subdivide e Tangent Surround Number of points to look at on either side of a point when computing the approximation to the tangent at that point Feather The Feather command feathers the edges of the selection This creates a smooth transition between the selection and its surroundings You normally feather selection borders with the Feather Edges option of the selection tools but you may feather them again with this command y xe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 232 of 421 Generated by docbook2odf Activating the Command e You can access this command from the image menubar through Select Feather Description of the Feather Selection dialog window Feather selection by 5 000 2 pixels Sharpen The Sharpen command reduces the amount of blur or fuzziness around the edge of a selection It reverses the effect of the Feather Selection command The new edge of the selection follows the dotted line of the edge of the old selection Anti aliasing is also removed Please do not confuse this command with the Sharpen filter Activating the Com
165. be extremely gentle when you change the pattern If you make a component triangle too big or if you move it too far even ever so slightly the preview screen will black out or more commonly you ll get stuck with a big shapeless particle cloud A word of advice When you have found a pattern you want to work with make only small changes and stick to variations of that pattern It s all too easy to lose a good thing Contrary to what you might believe it s really much easier to create a leaf or a tree with IFS Compose than to make a defined geometrical pattern where you actually Know what you re doing and end up with the pattern you had in mind For a brief introduction to IFS s see Foley and van Dam et al Computer Graphics Principles and Practice 2nd Ed Addison Wesley 1990 Options A Brief Tutorial GNU Image Manipulation Program Page 386 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o This is a rather complex plug in so to help you understand it we ll guide you through an example where you ll create a leaf or branch Many forms of life and especially plants are built like mathematical fractals i e a shape that reproduces or repeats itself indefinitely into the smallest detail You can easily reproduce the shape of a leaf or a branch by using four or more fractals Three fractals make up the tip and sides of the leaf and the fourth represents the ste
166. bles PRR BcreatecHallnewHimage BRR ChelmagewWidthill o BER RRR RRR RRR tChelmageHeight 10 BERR RRR tC helmagell cari eee Sg imp image new eee he lmageWidth eee he ImageHeight eee RERCe ET eee TT TTT BERR RRR Chelext SERRE EREEE abdeclaration foriitheltext eee wecreatecHlater BERR RRR theBuffer ENRERE added BR RRRRRRR RRR tC heLayerl See car eee gimp layer new eee helimage eR he lmagewWidth eR he lmageHeight See RGR IMAGE eee Payer eee OO eee RBNORMAL TTT eee TTT TTT TTT BERR RRRRRRRRE Bs endhoffourllocalfvariables BRRRRRRRE Codeihere BRRREEE BREE PTT TT BHRREEEE Script fu register RRR RRREE Script fu text box SHEER EEEREEEERERRRRRRERE CuncEname BERR RRRREE TextBox SERRE REE enublabel BRRRRRRREE CreatesHallsimpleiitextibox Hsizedito fit See aroundsithefuser schoiceflof text BERRRRRRRRERE Ont font size Bandicolor SHRRRREEREEEEE description SOR RRRREE Mi chacliTerry SERRE EEEERRRERRRR ERR author BERR RRRRRE Ccopyright 1997 8MichaeliTerry SHRRREREEEEEE copyright notice POR RRRRRR OctoberG 27 0199 7 SERRE EERRRRERRRRRRRRRRRRRE date icreated ee ee imageitypelithat amp thelscriptiworkslon BERBERS STRINGHEREEE Text SEEEREEEE TextBox Gli alstringlivariable SERRE SE FONTEREREREE Font SEEEEEEEE Charter SHHE alfontivariable BERGER SE ADJUSTMENTHEE Fontisize SERRE SOM1HLOOOH1H10H0H1 eee aBspin button SERRE SE
167. bly find however that the more you use it the more frustrated you become with the difficulty of selecting exactly what you what no more no less Perhaps the most frustrating aspect is that after you have released the mouse button you can t make small adjustments to the threshold you have to start over again from scratch More experienced users find that the Path and Color Select tools are often more efficient and use the Wand less Still it is useful for selecting an area within a contour or touching up imperfect selections It often works very well for selecting a solid colored or nearly solid colored background area Note that as the selected area expands outward from the center it does not only propagate to pixels that touch each other it is capable of jumping over small gaps The distance it can jump over is set in the Tool Options page of the Preferences dialog the Default threshold for Finding Continguous Regions By raising or lowering this value you can make the Magic Wand either more or less aggressive Filling with the Bucket Fill and Blend tools will also be affected How to Activate he Magic Wand Tool can be activated from an image menu as Tools Selection Tools Fuzzy Select from the Toolbox by clicking on the tool icon or from the keyboard using the shortcut z Z stands for Zauber the German word for Magic Key modifiers Defaults The Fuzzy Select tool does not have any special key modifiers only the on
168. bution of colors across the entire image and Other tools which don t fall into the other four categories In case you re curious in Gimp lingo a tool is a way of acting on an image that requires access to its display either to let you indicate what you want to do by moving the pointer around inside the display or to show you interactively the results of changes that you have made But if you want to think of a tool as a saw and an image as a piece of wood it probably won t do you a great deal of harm Most tools can be activated by clicking on an icon in the Toolbox Some however namely the Color tools are accessible only via the menus either as Too s gt Color Tools or as Layer gt Colors Every tool in fact can be activated from the Tools menu also every tool can be activated from the keyboard using an accelerator key In the default setup created when GIMP is first installed not all tools show icons in the Toolbox the Color tools are omitted You can customize the set of tools that are shown in the Toolbox using the Tools dialog There are two reasons you might want to do this first if you only rarely use a tool it might be easier to find the tools you want if the distracting icon is removed second if you use the Color tools a lot you might find it convenient to have icons for them easily available In any case regardless of the Toolbox you can always access any tool at any time using the Tools menu from an image menub
169. bvious the Text tool tries to protect you from it If you operate on a text layer and then later try to edit the text a message pops up warning you that your alterations will be undone and giving you three options 1 edit the text anyway 2 cancel 3 create a new text layer with the same text as the existing layer leaving the existing layer unchanged GNU Image Manipulation Program Page 40 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Chapter Getting Unstuck revhistory pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 41 of 421 Generated by docbook2odf Stuck All right okay you re stuck You re trying to use one of the tools on an image and nothing IS happening and nothing you try makes any difference Your fists are starting to clench and your face Is starting to feel warm Are you going to have to kill the program and lose all your work This sucks Well hold on a second This happens pretty frequently even to people who ve used the GIMP for a long time but generally the cause is not so hard to figure out and fix if you know what to look at Lets be calm and go through a checklist that will probably get you GIMPing happily again pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 42 of 421 Generated by docbook2odf
170. by the intensity of the corresponding pixel in the displace map drawables Both X and Y displace maps must be gray scale images and have the same size as the drawable This filter allows interesting distortion effects Options Using gradient to bend a text Follow following steps Start with opening your image Duplicate this image Activate this duplicate and make it gray scaled lt IMAGE gt Image Mode GrayScale Fill it with the wanted gradient This image will be your Displacement map with the dimensions of original image Activate original image Create a Text Layer with your text Set layer to image size right click on the layer in layer dialog and in the pop menu click on Layer to image size Note that letters in text layer lie on transparent background now this filter doesn t displace transparent pixels Only letters will be displaced GNU Image Manipulation Program Page 371 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Activate text layer Open Displace filter window Set parameters particularly displacement coefficient according to the result in Preview OK To get the wanted gradient first draw a black to white gradient Then use the Curves tool to modify the gradient curve Fractal Trace Overview This filter transforms the image with the Mandelbrot fractal it maps the image to the fractal You get to this filter via the Ima
171. called libexif which may not be available on all systems If GIMP is built with EXIF support enabled then loading a JPEG file with EXIF data and resaving the resulting image in JPEG format will cause the EXIF data to be preserved unchanged This ts not strictly speaking the right way for an image editor to handle EXIF data but it is better than simply removing it which is what earlier versions of GIMP did If you would like to see the contents of the EXIF data you can download from the registry an Exif Browser plug in If you are able to build and install it on your system you can access it as Filters gt Generic gt Exif Browser from the image menu See Installing New Plug ins for help pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 74 of 421 Generated by docbook2odf Preparing your Images for the Web One of the most common purposes GIMP Is used for is to prepare images for adding them to a web site This means that images should look as nice as possible while keeping the file size as small as possible This little step by step guide will tell you how to achieve a smaller file size with minimal degradation of image quality Images with an Optimal Size Quality Ratio An optimal image for the web depends upon the image type and the file format you have to use If you want to put a photograph with a lot of colors online you have to use JPEG as your primary file
172. canned raster graphics for color separation Six different encoding routines are supported each with one of three different image modes black and white grayscale and color Uncompressed TIFF images may be 1 4 8 or 24 bits per pixel TIFF images compressed using the LZW algorithm may be 6 8 or 24 bits per pixel Besides Postscript format TIFF is one of the most important formats for preliminary stages of printing It is a high quality file format which is perfect for images you want to import to other programs like FrameMaker or CorelDRAW A URL Uniform Resource Locator is a subdivision of Uniform Resource Identifiers URIs URLs identify a resource over a primary access mechanism commonly http or ftp and the location of the resource in the computer network The name of the URI scheme is therefore derived from the network protocol used for it as a rule Examples of that are http or ftp Since URLs are the first and most common kinds of URIs the terms are often used as synonyms A Uniform Resource Identifier URI is a string of characters that serves to identify an abstract or a physical resource URIs are used for the identification of resources in the Internet such as web pages miscellaneous data calling up web services but also for receivers of e mail for example and they are especially used in the Worldwide Web The XCF file type is special because it is GIMP s native file type that is it was designed specifically to store a
173. cations proprietary and only available to a limited set of developers blessed by Adobe This does not include the Gimp development team and the lack of information makes it very difficult to maintain up to date support for PSD files RGB in an acronym for Red Green Blue These are the three additive primary colors Blending together three light sources with these colors with different relative intensity you can get any visible color combination starting from black all three sources with intensities equal to zero to white all three sources equal and at full light For more information see Color model in this glossary GNU Image Manipulation Program Page 406 of 421 Generated by docbook2odf y xe e N E O O 2 0 O xe a 2 xe o 4 hn S o Sample Merge is a technique useful when working with more than one layer where operations that affect one layer may take advantage of color or pixel information on all visible layers Consider selection by color as an example of a time that this function may be useful With this technique GIMP uses more pixels to calculate a transitional color for instance for interpolation This technique results in a better image but it requires more time for the calculations TGA Targa Image File format supports compression to 8 16 24 or 32 bits per pixel It was originally developed by the Truevision company TIFF Tagged Image File Format was developed primarily for s
174. cbook2odf Introduction to the GIMP Menus Eile Xtns Help There are many places in GIMP where you can find menus The aim of this chapter is to explain all the commands that are accessible from the menus in the Toolbox and Image windows All the context menus and the menu entries for the other dialogs are described elsewhere in the chapters that describe the dialogs themselves Context Menus If you right click on certain parts of the GIMP interface a context menu opens which leads to a variety of functions Some places where you can access context menus are e Clicking on an image window displays the Image menu This is useful when you are working in full screen mode without a menubar e Clicking on a layer in the Layers Dialog or on a channel in the Channels Dialog displays functions for the selected layer or channel e Right clicking on the image menubar has the same effect as left clicking e Right clicking on the title bar displays functions which do not belong to GIMP but to the window manager program on your computer Detachable Submenus IThere is an interesting property associated with some of the menus in GIMP These are any of the menus from the Toolbox menubar and any of their submenus as well as the Image context menu you get by right clicking on the image window and any of its submenus You can tell that a menu item leads to a submenu because there is an icon next to it When you bring up any of these me
175. ch are currently defined You can click on the New button or the Duplicate button to create a new measurement unit as described below Description of the list elements e Saved If this column is checked a unit definition will be saved when GIMP exits Some units are always kept even if they are not marked with a check These are highlighted in the list e D The string GIMP uses to identify the unit in its configuration files e Factor How many units make up an inch e Digits This field is a hint for numerical input fields It specifies how many decimal digits the input field should provide to get approximately the same accuracy as an inch input field with two decimal digits e Symbol The unit s symbol if it has one e g for inches The unit s abbreviation is used if doesn t have a symbol e Abbreviation The unit s abbreviation e g cm for centimeters e Singular The unit s singular form which GIMP can use to display messages about the unit e Plural The unit s plural form which GIMP can use to display messages about the unit Defining New Units You can display the dialog shown above by clicking on either the New button or the Duplicate button on the Unit Editor dialog The input fields on the dialog are described above If you click on the New button the dialog looks as shown If you click on the Duplicate button the values initially displayed in the input fields of the dialog are the values of the
176. ch image display although their contents are somewhat different The Toolbox is the only place to access the Xtns Extensions menu You may find other entries in this menubar which are not described here They are not part of standard GIMP but have been added by some of the plug ins You can find more information about the additional menu entries in the documentation for the plug ins Acquire P Paste as New From Clipboard Screen Shot TWAIN The Acquire submenu of the Toolbox s File menu contains a list of ways you can import images into the GIMP This allows you to import images from sources other than a disk or the network such a screen capture or an image from a scanner Activating the Submenu e You can access this command in the Toolbox menu File Acquire Submenu entries These commands vary somewhat depending upon your system since the GIMP makes calls to system functions GNU Image Manipulation Program Page 206 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o The Preferences command The File Preferences command displays the Preferences dialog which lets you alter a variety of settings that affect the look feel and performance of the GIMP Activating the Command e You can access this command in the Toolbox menu bar through File Preferences The Dialogs sub menu Open Recent Acquire Create Ne
177. checking the menu entry in the LayerMask submenu or by Alt clicking or Ctrl Alt clicking again on the layer mask s thumbnail Mask to Selection The Mask to Selection command converts the layer mask of the active layer into a selection which replaces the selection that is already active in the image White areas of the layer mask are selected black areas are not selected and gray areas are converted into feathered selections The layer mask itself is not modified by this command Activating the Command e You can access this command from the image menubar through Layer Mask Mask to Selection e or from the pop up menu you get by right clicking on the active layer in the Layers Dialog Add Layer Mask to Selection The Add to Selection command converts the layer mask of the active layer into a selection which is added to the selection that is already active in the image White areas of the layer mask are selected black areas are not selected and gray areas are converted into feathered selections The layer mask itself is not modified by this command GNU Image Manipulation Program Page 271 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 3 S o Activating the Command e You can access this command from the image menubar through Layer Mask Add to Selection e or from the pop up menu you get by right clicking on the active layer in the Layers Dialog Subtract La
178. ck is simply the list of layers in the Layers dialog The Stack submenu contains operations which either select a new layer as the active layer or change the position of the active layer in the layer stack Activating the Submenu e You can access this submenu from the image menubar through Layer Stack The Contents of the Stack Submenu The Stack submenu contains the following commands Select Previous Layer The Select Previous Layer command selects the layer just above the active layer in the layer stack The command highlights the layer in the Layers Dialog and makes it the new active layer If the active layer is already at the top of the stack this menu entry is insensitive and grayed out GNU Image Manipulation Program Page 261 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o Note that on a standard Windows style English keyboard the default shortcut Page Up does not refer to the key on the numeric keypad but to the other Page Up key in the group of six keys to the left of the numeric keypad The keyboard shortcuts for Select Previous Layer and Select Next Layer may be very useful if you frequently pick colors from one layer to use for painting on another layer especially when you use them with the color picker tool which you get by holding down the Ctrl key with most of the painting tools Activating the Command e You can access this command from the image m
179. ck to using the clone tool effectively is to be able to find a different part of the image that can be used to copy over the unwanted part if the area surrounding the unwanted object is very different from the rest of the image you won t have much luck For example if you have a lovely beach scene with a nasty human walking across the beach who you would like to teleport away you will probably be able to find an empty part of the beach that looks similar to the part he is walking across and use it to clone over him It is quite astonishing how natural the results can look when this technique works well Consult the Clone Tool Help for more detailed instructions Cloning is as much an art asa science and the more you practice at it the better you will get At first it may seem impossible to produce anything except ugly blotches but persistence will pay off In some cases you may be able to get good results by simply cutting out the offending object from the image and then using a plug in called Resynthesizer to fill in the void This plug in is not included with the main GIMP distribution but it can be obtained from the author s Resynthesizer web site As with many things your mileage may vary GNU Image Manipulation Program Page 72 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Removing Red eye When you take a flash picture of somebody who is looking directly toward
180. cript Fu and then build a handy script that you can add to your toolbox of scripts The script prompts the user for some text then creates a new image sized perfectly to the text We will then enhance the script to allow for a buffer of space around the text We will conclude with a few suggestions for ways to ramp up your knowledge of Script Fu This section as adapted from a tutorial written for the Gimp 1 User Manual by Mike Terry Getting Acquainted With Scheme Let s Start Scheme ing The first thing to learn is that Every statement in Scheme is surrounded by parentheses The second thing you need to know is that The function name operator is always the first item in the parentheses and the rest of the items are parameters to the function However not everything enclosed in parentheses is a function they can also be items in a list but we ll get to that later This notation is referred to as prefix notation because the function prefixes everything else If you re familiar with postfix notation or own a calculator that uses Reverse Polish Notation Such as most HP calculators you should have no problem adapting to formulating expressions in Scheme The third thing to understand Is that Mathematical operators are also considered functions and thus are listed first when writing mathematical expressions This follows logically from the prefix notation that we just mentioned Examples Of Prefix Infix And Postfix No
181. cript functions script fu abc because then when they re listed in the procedural database they ll all show up under script fu when you re listing the functions This also helps distinguish them from plug ins Registering The Function Now let s register the function with Gimp This is done by calling the function script fu register When Gimp reads in a script it will execute this function which registers the script with the procedural database You can place this function call wherever you wish in your script but usually place it at the end after all my other code Here s the listing for registering this function I will explain all its parameters in a minute PTT TT BEREREEE Script fu register BORG RRRRE Script fu text box SHEE EEEEREEERRRRRRRRRERE CuncEname ae eee enublabel BERR ORRRRE CreatesHallsimple textibox sizedito fit See aroundsithefuser schoiceflof ftext BERR RRRRRRERE ont font size Bandicolor SHRRRREEREEEEE description POOR RRRRRE Mi chacliTerry SERRE EREERERERRRRRRRRRRRRRREE author BRR RRRRRRE copyright 1997 8MichaeliTerry SHRREEREEEEEE copyright notice PORE OctoberG 27 0199 7 SERRE EERRRERERRRRRRRRRRRRRE date icreated eee ee imageltypelithat amp thelscriptiworkslon BERGER S STRINGHEEEEE Text SEERREEEE TextBox Gli astringlivariable SERRE SE FONTEREREREE Font SEREEREEE Charter HHE alfontivariable BER RRRRRRESE ADJUSTMENTHEE Fontisize SEEEE SOM1HLO
182. d Activating the Command e You can access this command from the image menubar through Layer Stack Select Top Layer e or by using the keyboard shortcut Home e or simply by clicking on the layer name in the Layers Dialog Select Bottom Layer GNU Image Manipulation Program Page 262 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o With the Select Bottom Layer command you can make the bottom layer in the stack become the active layer for the image It is then highlighted in the Layers dialog If the bottom layer of the stack is already the active layer this menu entry Is Insensitive and grayed out Note that on a standard Windows style English keyboard the default keyboard shortcut refers to the End key in the group of six keys to the left of the numeric keypad not to the one in the numeric keypad Activating the Command e You can access this command from the image menubar through Layer Stack Select Bottom Layer e by using the keyboard shortcut End e or simply by clicking on the name of the layer in the Layers dialog Raise Layer The Raise Layer command raises the active layer one position in the layer stack If the active layer is already at the top or if there is only one layer this menu entry is insensitive and grayed out If the active layer is at the bottom of the stack and it does not have an alpha channel it cannot be raised until you add an alpha c
183. d e You can access this command from the image menubar through Layer Transparency Add to Selection Example Hi New layer o Background Subtract from Selection The Subtract from Selection command creates a selection in the image from the pixels of the active layer according to their transparency Opaque areas are fully selected transparent areas are unselected and translucent areas are partially selected This selection is subtracted from an existing selection The alpha channel itself is not changed pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o GNU Image Manipulation Program Page 275 of 421 Generated by docbook2odf Activating the Command e You can access this command from the image menubar through Layer Transparency Subtract from Selection e or from the pop up menu which appears when you right click on the active layer in the Layer Dialog Example TEE New layer Background Intersect with Selection The Intersect with Selection command creates a selection in the image from the pixels of the active layer according to their transparency Opaque areas are fully selected transparent areas are unselected and translucent areas are partially selected This selection is intersected with an existing selection only common parts of both selections are kept The alpha channel itself is not changed Activating the Command e You can access this command from the image menubar th
184. d selected areas especially for stem Levels tool The Level tool provides features similar to the Histogram tool but can also change the intensity range of the active layer or selection Activate Tool You can call the Level Tool in the following order from the image menu Tools Color Tools Levels Options Adjust Color Levels Background 2 Untitled Channel Walue Reset Channel All Channels bom Ga aml all a A Preview FJ Feset A Cancel Pox Although this tool is not present in Tool box nevertheless it has a Tool Option Dialog under the Toolbox These options are described here pe O N E O O 2 S O xe a 2 xe o 4 G d 0 S o GNU Image Manipulation Program Page 144 of 421 Generated by docbook2odf Curves Tool The Curves tool is the most sophisticated tool used to adjust the tonality of images Activate Tool The Curves Tool can be called in the following order from the image menu Tools Color Tools Curves Adjust Color Curves mE Adjust Color Curves Background 2 Untitled Channel Walue El Reset Channel All channels Cure Type gt Open al Save o w A Preview FJ Reset A Cancel Pox Although this tool is not present in Tool box nevertheless it has a Tool Option Dialog under the Toolbox These options are described here Posterize Tool This tool is designed to intelligently weigh the pixel colors of the selection or
185. d Rectangle from the image menu How to Activate e From the image menu bar Tools Selection Tools Rect Select e By clicking on the tool icon in the ToolBox e By using the keyboard shortcut R Key modifiers See Selection Tools for help with modifier keys that affect all these tools in the same way Only effects that are specific to the Rectangle Select tool are explained here e Ctrl Pressing the Ctrl key after starting your selection and holding it down until you are finished causes your starting point to be used as the center of the selected rectangle instead of a corner Note that if you press the Ctrl key before starting to make the selection the resulting selection will be subtracted from the existing selection e Shift Pressing the Shift key after starting your selection and holding it down until you are finished constrains the selection to be square Note that if you press the Shift key before starting to make the selection the resulting selection will be added to the existing selection e Ctrl Shift Pressing both keys after starting your selection combines the two effects giving you a square selection centered on your starting point Note that pressing these keys before starting your selection intersects the resulting selection with the existing one Tool Options GNU Image Manipulation Program Page 107 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o
186. d instead Activating the Command e You can access this command from the image menubar through File Save as e or by using the keyboard shortcut Shift Ctrl S The Basic Save as Dialog There are two different forms of the Save as dialog The simple form only lets you type in the filename and choose the directory the file should be saved in If the folder you want is not on the list you can type in the path to the directory along with the filename You can also click on the small triangle to display the full folder browser You must also choose the image format by selecting the file extension e g xcf or png Name 2zinnias png Save in folder fOMesimages t Browse for other folders t Select File Type By Extension The Save Dialog with a Browser The left panel is divided into two parts The upper part lists your main directories and your storage devices you cannot modify this list The lower part lists your bookmarks you can add or remove bookmarks To add a bookmark select a directory or a file in the middle panel and click on the Add button at the bottom of the left panel You can also use the Add to bookmarks command in the context menu which you get by clicking the right mouse button You can delete a bookmark by selecting it and clicking on the Remove button The middle panel displays a list of the files in the current directory Change your current GNU Image Manipulation Program Page 218 of 421 Generated by
187. de variety of formats It is important to realize that the only format capable of saving all of the information in an image including layers transparency etc is GIMP s native XCF format Every other format preserves some image properties and loses others When you save an image GIMP tries to let you know about this but basically it is up to you to understand the capabilities of the format you choose Your image should be exported before it can be saved as JPEG for the following reasons JPEG cant handle transparency Flatten Image The export conversion won t modify your original image Ignore 3 Cancel Export As stated above there is no file format with the exception of GIMP s native XCF format that is capable of storing all the data in a GIMP image When you ask to save an image in a format that will not completely represent it GIMP notifies you of this tells you what kind of information will be lost and asks you whether you would like to export the image in a GNU Image Manipulation Program Page 53 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 hn 0 S o form that the file type can handle Exporting an image does not modify the image itself so you do not lose anything by doing this When you close an image possibly by quitting GIMP you are warned if the image is dirty that is if it has been changed without subsequently being saved Saving an image i
188. ded that the level of fundamental change to the inner workings of the program justified calling the new stable version 2 0 GIMP 2 0 0 was released on March 23 2004 For GIMP 2 2 the developers aimed at a short cycle adding a number of important features that did not require instability inducing low level changes GIMP 2 2 0 was released on December 19 2004 This section briefly describes the new features that were added in GIMP 2 2 as well as the features that were introduced in GIMP 2 0 Here is a brief summary of some of the most important new features introduced in GIMP 2 2 There are many other smaller changes that long time users will notice and appreciate or complain about There are also important changes at the level of plugin programming and script fu creating that are not covered here Interoperability and standards support e You can drag and drop or copy and paste image data from the GIMP to any application which supports image png drops currently Abiword and Kword at least and image xml svg drops Inkscape supports this one So you can copy and paste curves into the GIMP from Inkscape and then drag a selection into Abiword to include it inline in your document e Patterns can now be any supported GtkPixbuf format including png jpeg xom and others e GIMP can load gradients from SVG files and palettes from ACT and RIFF files e Drag and drop support has been extended You can now drop files and URIs onto an image w
189. dialog is embedded in a Layers Channels and Paths dock you can see the name of the active image in the Image Menu at the top of the dock Otherwise you can add an Image Menu to the dock by choosing Show Image Menu from the Tab menu If you are familiar with the Layers dialog you have a head start because the Paths dialog is in several ways similar It shows a list of all paths that exist in the image with four items for each path If the list is non empty at any given moment one of the members is the image s active path which will be the subject of any operations you perform using the dialog menu or the buttons at the bottom the active path is shown highlighted in the list Clicking on any of the entries will make it the active path Right clicking on any entry in the list brings up the Paths Menu You can also access the Paths Menu from the dialog Tab menu Buttons The buttons at the bottom of the Paths dialog all correspond to entries in the Paths menu accessed by right clicking on a path list entry but some of them have extra options obtainable by holding down modifier keys while you press the button Paths Menu GNU Image Manipulation Program Page 161 of 421 Generated by docbook2odf xe O N E O O 2 S O xe a 2 xe o d 3 S o 4 Path Tool ET Edit Path Attributes J New Path Raise Path Lower Path Duplicate Path Delete Path Merge Visible Paths ae Path to Selec
190. different from simply reducing the image size by scaling it since no pixels and no image information are removed Fit Canvas to Layers The Fit Canvas to Layers command adapts the canvas size that is the drawing area to the size of the largest layer in the image in both width and height Activating the command e You can access this command from the image menubar through Image Fit Canvas to Layers Scale Image The Scale Image command enlarges or reduces the physical size of the image by changing the number of pixels it contains It changes the size of the contents of the image and resizes the canvas accordingly It operates on the entire image If your image has layers of different sizes making the image smaller could shrink some of them down to nothing since a layer cannot be less than one pixel wide or high If this happens you will be warned before the operation is performed If you only want to scale a particular layer use the Scale Layer command If scaling would produce an image larger than the Maximum new image size set in the Environment page of the Preferences dialog which has a default of 64Mb you are warned and asked to confirm the operation before it is performed You may not experience any problems if you confirm the operation but you should be aware that very large images consume a lot of resources and extremely large images may take more resources than you have causing GIMP to crash or not perform well
191. docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o directory by double left clicking on a directory in this panel Select a file with a single left click You can then save to the file you have selected by clicking on the Save button Note that a double left click saves the file directly You can right click on the middle panel to access the Show Hidden Files command The selected image Is displayed tn the Preview window if it is an image created by GIMP File size resolution and the image s composition are displayed below the preview window If your image has been modified by another program click on the preview to update it Enter the filename of the new image file here If the image has already been saved GIMP suggests the same filename to you If you click on Save the file is overwritten This drop down list is only available in the basic form of the dialog It provides a list of bookmarks for selecting a directory in which to save your file Above the middle panel the path of the current directory is displayed You can navigate along this path by clicking on one of the buttons If you want to save the image into a folder that doesn t yet exist you can create it by clicking on Create Folder and following the instructions This button shows All Files by default This means that all file types will be displayed in the middle panel even if they are not images You can fi ter the list for a p
192. does not have any special key modifiers only the ones that affect all selection tools in the same way See Selection Tools for help with these Options pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 112 of 421 Generated by docbook2odf Select By Color vode a Ee ET a Z Antialiasing Feather edges Radius 10 0 Finding Similar Colors fv Select transparent areas Sample merged Threshold EE Cl 15 0 _ 5 See Selection Tools for help with options that are common to all these tools Only options that are specific to the Select by Color tool are explained here Note that they are the Same options as the Magic Wand tool has Regarding moving selection this tool does nt work like others when selection by color is created you can move it only if you select another selection tool Scissors Tool The Intelligent Scissors tool is an interesting piece of equipment it has some features in common with the Lasso some features in common with the Path tool and some features all its own It is useful when you are trying to select a region defined by strong color changes at the edges To use the Scissors you click to create a set of control nodes at the edges of the region you are trying to select The tool produces a continuous curve passing through these control nodes following any high contrast edges it can find If you are lucky t
193. doing this Even if an image does not seemed washed out often you can increase its Impact by pushing up the saturation a bit Veterans of the film era sometimes call this trick Fujifying after Fujichrome film which is notorious for producing highly saturated prints When you take pictures in low light conditions in some cases you have the opposite problem too much saturation In this case too the Hue Saturation tool is a good one to use only by reducing the saturation instead of increasing it Adjusting Sharpness Unblurring If the focus on the camera is not set perfectly or the camera is moving when the picture is taken the result is a blurred image If there is a lot of blurring you probably won t be able to do much about it with any technique but if there is only a moderate amount you Should be able to improve the image The most generally useful technique for sharpening a fuzzy image is called the Unsharp Mask In spite of the rather confusing name which derives from its origins as a technique used by film developers its result is to make the image sharper not unsharp It is a plug in and you can access it as Filters gt Enhance gt Unsharp Mask in the image menu There are two parameters Radius and Amount The default values often work pretty well so you should try them first Increasing either the radius or the amount increases the strength of the effect Don t get carried away though if you make the unsharp mask
194. doing this First you have to activate this capability by checking the Use dynamic keyboard Shortcuts option in the Interface item of the Preferences menu This option is usually not checked to prevent accidental key presses from creating an unwanted shortcut While you re doing that also check the Save keyboard shortcuts on exit option so that your shortcut will be saved To create a keyboard shortcut simply place the mouse pointer on a command in the menu it will then be highlighted Be careful that the mouse pointer doesn t move and type a sequence of three keys keeping the keys pressed You will see this sequence appear on the right of the command If you type a sequence which has already been used the command which is associated with this shortcut will be executed and no new shortcut will be created It is best to use the CtrlAltKey sequence for your custom shortcuts Action Shortcut far File p Context Debug b i Help b gf Edit b Select gt amp View e Ealimage gt gt Drawable gt PoLayers gt Ea Channels gt Paths gt Tools gt Dialogs gt Gi Plug Ins e O QuickMask 4 d To edit a shortcut key click on the corresponding row and Ehe type a new accelerator or press backspace to clear You get to this Editor by clicking on Configure keyboard shortcuts in the Interface item of the Preferences menu As shown in this dialog you can select the command you w
195. e The colormap of an indexed image Is shown in the Indexed Palette dialog which should not be confused with the Palettes dialog The Palettes dialog shows a list of all of the palettes available the Colormap dialog shows the colormap of the currently active image if it is an indexed image otherwise it shows nothing You can however create an ordinary palette from the colors in an indexed image actually from the colors in any image To do this choose Import Palette from the right click popup menu in the Palettes dialog this pops up a dialog that gives you several options including the option to import the palette from an image You can also import any of GIMP s gradients as a palette This possibility becomes important if you want to create a set of indexed images that all use the same set of colors When you convert an image into indexed mode a major part of the process Is the creation of an indexed palette for the image How this happens is described in detail in Briefly you have several methods to choose from one of which is to use a specified palette from the Palettes dialog Thus to sum up the foregoing ordinary palettes can be turned into indexed palettes when you convert an image into indexed mode indexed palettes can be turned into ordinary palettes by importing them into the Palettes dialog Text and Fonts One of the greatest improvements of GIMP 2 0 over GIMP 1 2 Is in the handling of text In GIMP 2 0
196. e Interpolation Supersampling Clip result Number of grid lines Shearing Information window Perspective Tool The Perspective Tool is used to change the perspective of the active layer content of the selection boundaries or of a path When you click on the image according to the Preview type you have selected a rectangular frame or a grid pops up around the selection or around the whole layer if there is no selection with a handle on each of the four corners By moving these handles by click and drag you can modify the perspective At the same time a Transformation informations pop up which lets you valid the transformation At the center of the element a point lets you move the element by click and drag Activate Tool e The Perspective Tool can be called in the following order from the image menu Tools Transform Tools Perspective GNU Image Manipulation Program Page 136 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o e The Tool can also be called by clicking the tool icon Key modifiers Defaults Options Transform Direction Forward traditional C Backward corrective Interpolation Linear l Supersampling Clip result The dialog window of the Perspective tool Flip Tool The Flip tool provides the ability to flip layers or selections either horizontally or vertically When a selection
197. e The Mode submenu contains commands which let you change the color model of the image There are three modes Activating the Submenu e You can access this submenu from the image menubar through Image Mode The Contents of the Mode Submenu e RGB e Grayscale e Indexed e Compose e Decompose RGB mode The RGB command converts your image to RGB mode See the RGB description in the Glossary for more information Normally you work in this mode which is well adapted to the screen It is possible to convert an RGB image to Grayscale or Indexed mode but be careful once you have saved the image you can no longer retrieve the RGB colors so you should work on a copy of your image Activating the command e You can access this command from the image menu bar through Image Mode RGB Grayscale mode You can use the Grayscale command to convert your image to grayscale with 256 levels of gray from O black to 255 white See the glossary for more information about grayscale mode Activating the Command GNU Image Manipulation Program Page 247 of 421 Generated by docbook2odf y xe O N E O O 2 S O xe a 2 xe o d 3 S o e You can access this command from the image menubar through Image Mode Grayscale Indexed mode The Indexed command converts your image to indexed mode See indexed colors in the Glossary for more information about Indexed Color Mode Activating the Dialog e You can acc
198. e and options To save it differently in any respect use either Save As or Save A Copy If you quit without having saved your image GIMP asks you if you really want to do so if the Confirm closing of unsaved images option is checked in the Environment page of GNU Image Manipulation Program Page 217 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o the Preferences dialog Activating the Dialog e You can access this command in the image menu bar through File Save e or from the keyboard by using the shortcut CtrlS Save as The Save as command brings up the File Save dialog In its basic form as shown below this gives you a text box to use to assign a name to the file and a dropdown list of bookmarks to use to select a directory to save it in Normally the file format is determined by the extension you use in the file name i e jog for a JPEG file You can use the Select File Type option expander to pick a different file type but you should avoid doing this unless absolutely necessary to avoid confusion If the directory you want is not in the list of bookmarks click on Browse for other folders to expand the dialog into its full form You can find an explanation of the layout and help on creating and using bookmarks in the Files section If you saved the image previously and don t need to change the file name or any of the options you can use the Save comman
199. e in e L B5 Offset Width Height bo Efo Erres foo fpo En fl This page lets you customize the default properties of GIMP s grid which can be toggled on or off using View Show Grid from the image menu The settings here match those in the Configure Image Grid dialog which can be used to reconfigure the grid for an existing image by choosing Image Configure Grid from the image menu See the Configure Grid dialog section for information on the meaning of each of the settings Interface GNU Image Manipulation Program Page 185 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o User Interface Previews f Enable layer amp channel previews Default layer amp channel preview size Medium Navigation preview size Medium Keyboard Shortcuts A Show menu mnemonics access keys Use dynamic keyboard shortcuts Contigure Keyboard Shortcuts f Save keyboard shortcuts on exit Save Keyboard Shortcuts Now Reset Saved Keyboard Shortcuts to Default Values Theme GNU Image Manipulation Program Generated by docbook2odf Page 186 of 421 pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o Select Theme test fhome bill gimp 2 1themes test Default usr localigimp 2 1 share gimp 1themes Default Small usr localigimp 2 1 share gimp 1themes Smaill ce Reload Current Theme This page lets you select a theme which
200. e Acquire Paste as New from the Toolbox menu Support for this is somewhat variable however so your best bet is to try it and see whether it works e Image Browser In Linux you might want to take a look at a program called gthumb an image management application that in several ways nicely complements GIMP In gthumb you can cause an image to open in GIMP either by right clicking on the icon and selecting GIMP from among the list of options or by dragging the icon into the GIMP Toolbox See the gthumb home page for more information Other similar applications gqview xnview When you open a file using the File menu or any other method GIMP needs to determine what type of file it is Unless there is no alternative GIMP does not simply rely on the extension such as jpg to determine the file type because extensions are not reliable they vary from system to system any file can be renamed to have any extension and there are many reasons why a file name might lack an extension Instead GIMP first tries to recognize a file by examining its contents most of the commonly used graphics file formats have magic headers that permit them to be recognized Only if the magic yields no result does GIMP resort to using the extension Saving Files There are several commands for saving images A list and information on how to use them can be found in the section covering the File menu GIMP allows you to save the images you create in a wi
201. e Layer Mask As soon as you create a layer mask it acts on the image The Disable Layer Mask command allows you to suspend this action When you click on the menu entry a check IS displayed next to it and the border of the layer mask s thumbnail in the Layers Dialog turns red Activating the Command e You can access this command from the image menubar through Layer Mask Disable Layer Mask e or by holding down the Alt key Ctrl Alt on some systems and single clicking on the GNU Image Manipulation Program Page 270 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o layer mask s thumbnail in the Layers Dialog e You can undo this action by unchecking the menu entry in the LayerMask menu or by Alt clicking or Ctrl Alt clicking again on the layer mask s thumbnail Show Layer Mask The Show Layer Mask command lets you see the layer mask better by turning the image Invisible When you click on the menu entry a check Is displayed next to it and the layer mask s thumbnail in the Layers Dialog is shown with a green border The layer itself is not modified you can turn it visible again later Activating the Command e You can access this command from the image menubar through Layer Mask Show Layer Mask e or by holding down the Alt key Ctrl Alt on some systems and single clicking on the layer mask s thumbnail in the Layers Dialog e You can undo this action by un
202. e an object from a single color background Activating the Command e You can access this command from the image menubar through Layer Autocrop Layer Align Visible Layers With the Align Visible Layers command you can very precisely position the visible layers those marked with the eye icon This degree of precision is especially useful when you are working on animations which typically have many small layers Clicking on Align Visible Layers displays a dialog which allows you to choose how the layers should be aligned In GIMP 1 2 the default base for the alignment was the top visible layer in the stack In GIMP 2 the default alignment base is the edge of the canvas You can still align the image on the bottom layer of the stack even if it is invisible by checking Use the invisible bottom layer as the base in the dialog GNU Image Manipulation Program Page 281 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Activating the Command e You can access this command from the image menubar through Layer Align Visible layers There is no default keyboard shortcut Description of the Layer Align dialog Horizontal style Horizontal base Lett edge Vertical style None Vertical base Grid size pompo lo xX ignore the bottom layer even if visible Use the invisible bottom layer as the base o_ 3 o N x e o 2 8 o 3 gt 2 a
203. e for Affect that the left button Transform Layer is selected If you then click the mouse inside the image and drag it you will see a grid appear that rotates as you drag When the grid looks right click rotate or press the enter key and the image will be rotated Now as a matter of fact it isn t so easy to get things right by this method you often find that things are better but not quite perfect One solution is to rotate a bit more but there is a disadvantage to that approach Each time you rotate an image because the rotated pixels don t line up precisely with the original pixels the image inevitably gets blurred a little bit For a single rotation the amount of blurring is quite small but two rotations cause twice as much blurring as one and there is no reason to blur things more than you have to A better alternative is to undo the rotation and then do another adjusting the angle Fortunately GIMP provides another way of doing it that is considerably easier to use In the Rotate Tool Options for the Transform Direction you can select Backward Corrective When you do this instead of rotating the grid to compensate for the error you can rotate it to ine up with the error If this seems confusing try it and you will see that it is quite straightforward Note New in GIMP 2 2 is the option to preview the results of transformations instead of just seeing a grid This makes it easier to get things right on the first try
204. e histogram only for the contents of the selection e Shortcuts are now shared across all GIMP windows GNU Image Manipulation Program Page 7 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o Running GIMP Most often you start GIMP either by clicking on an icon if your system Is set up to provide you with one or by typing gimp on a command line If you have multiple versions of the GIMP installed you may need to type gimp 2 2 to get the latest version You can if you want give a list of image files on the command line after the program name and they will automatically be opened by GIMP as it starts It is also possible though to open files from within GIMP once it is running In most operating systems you can set things up so that various types of image files are associated with GIMP and cause it to start automatically when icons for them are double clicked If you want to cause a certain file type to automatically open in GIMP you should associate it with gimp remote gimp win remote under Windows rather than with gimp The gimp remote program is an auxiliary that comes with gimp If gimp is not already running on the system when gimp remote is executed it is started and the image given as argument to gimp remote Is loaded If gimp is already running though the image Is simply loaded into the already running program Command Line Arguments Ordinar
205. e image menu Select Save to Channel Usage Open an image or begin a new document Activate the Quickmask using the left bottom button in the image window If a selection is present the mask is initialized with the content of the selection Choose a drawing tool and use it with greyscale colors on the QuickMask Deactivate the Quickmask using the left bottom button in the image window Path dialog i S 1 concave The Paths dialog is used to manage paths allowing you to create or delete them save them convert them to and from selections etc GNU Image Manipulation Program Page 160 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o The Paths dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in several ways Dialog call e From the Toolbox menu File Dialogs Paths e From the Toolbox menu File Dialogs Create New Dock Layers Channels and Paths This gives you a dock containing three dialogs with the Paths dialog one of them e From an image menu Dialogs Paths e From the Tab menu in any dockable dialog Add Tab Paths Using the Paths dialog Each path belongs to one image paths are components of images just like layers The Paths dialog shows you a list of all paths belonging to the currently active image Switching images causes the dialog to show a different list of paths If the Paths
206. e last window displaying an image the image Itself is closed However if you have made changes to the image which you have not yet saved you are asked for confirmation Activating the Command e You can access this command from the image menubar through View New View GNU Image Manipulation Program Page 237 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Dot for Dot The Dot for Dot command enables and disables Dot for Dot mode If it is enabled checked and the zoom factor is 100 every pixel in the image Is displayed as one pixel on the screen If it is disabled the image is displayed at its real size the size it will have when it is printed For Dot for Dot mode to work properly the resolution of the image must be the same as the screen resolution in the Preferences menu Enabling this mode is recommended if you are working on icons and web graphics If you are working on images intended to be printed you should disable Dot for Dot mode Activating the Command e You can access this command from the image menubar through View Dot for Dot Zoom Q Zoom Out Zoom In n q Fit Image in Window Shift Ctri E E Fit Image to Window 16 1 1600 8 1 800 4 1 400 2 1 200 1 1 100 1 2 50 1 4 25 1 8 12 5 1 16 6 25 Other 144 The Zoom submenu contains various commands which affect the magnification of the image in the image
207. e mouse button both selections are added together You could subtract the extra part of the first selection in a similar way by pressing Ctrl To correct selection defects precisely use the Quick Mask GNU Image Manipulation Program Page 59 of 421 Generated by docbook2odf pe O N 4 O O 2 S O xe a 2 xe o G d 3 S o Dialogs and Docking Creating Dialogs Most dockable dialogs can be created in more than one way but all of them can be created using the File Dialogs menu from the Main Toolbox or by using the Add command in the Tab menu from any dialog As a convenience there are also three pre built docks you can create using the File Dialogs Create New Dock menu path from the Main Toolbox Just because you have a lot of flexibility does not mean that all choices are equally good There are at least two things we recommend 1 Keep the Tool Options dialog docked directly beneath the Main Toolbox at all times 2 Keep the Layers dialog around at all times in a separate dock from the Main Toolbox with an Image Menu above it Use Show Image Menu in the dialog Tab menu to display the Image menu if you have somehow lost it Removing Tabs If you want to remove a dialog from a dock there are two ways you can do it First if you click on the drag handle area and drag the dialog away releasing it someplace other than a docking bar it will form a new dock in its own right Second clicking on the
208. e placed in a new layer So the Image will not be modified all modifications occuring in this layer Starting filter You get to this filter via the Image menu through Filters Render Gfig Options GNU Image Manipulation Program Page 398 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o File Edit Tool options This tool has no options X Stroke Object Details XY position 0 0 Show grid Snap to grid x Show image Combine filters Combine filters introduction The combine filters associate two or more images into a single image Depth Merge Overlap Offset Scale 1 Scale 2 1 000 E x conce Dar GNU Image Manipulation Program Page 399 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 1 S o Depth Merge is a Combine Filter that is useful to combine two different pictures Overview lt combines the two pictures selected as sources by blending them Darkest values are predominant in the resulting image This could be done using blending modes but in this case there aren t any options To work with this filter at least two images are needed that have to be same sized Accessing this Filter This filter is tn Filters Combine Depth Merge Options Film Image Selection _ Fit Height to Images Available Images On Film Height 256 l Wilber xcf 1 Wilber xcf 1 Co
209. e resulting image looks grainy You can smooth out the graininess by blurring the image but then you will also lose sharpness There are a couple of approaches that may give better results Probably the best if the graininess is not too bad is to use the filter called Selective Blur setting the blurring radius to 1 or 2 pixels The other approach is to use the Despeckle filter This has a nice preview so you can play GNU Image Manipulation Program Page 71 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o with the settings and try to find some that give good results When graininess is really bad though it is often very difficult to fix by anything except heroic measures i e retouching with paint tools Softening Every so often you have the opposite problem an image is too crisp The solution is to blur it a bit fortunately blurring an image is much easier than sharpening it Since you probably don t want to blur it very much the simplest method is to use the Blur plug in accessed via Filters gt Blur gt Blur from the image menu This will soften the focus of the Image a little bit If you want more softening just repeat until you get the result you desire Removing Unwanted Objects from an Image There are two kinds of objects you might want to remove from an image first artifacts caused by junk such as dust or hair on the lens second things that were really
210. e screenshot e t can also be activated by using Shift Q shortcut Creating a Quick Mask To initialize a Quick Mask click the bottom left button in the image window If a selection was active in your image then its content appears unchanged while the border is covered by a tranlucent red color If no selection was active then all the image is covered by a tranlucent red color At every moment you can hide the maskby clicking on the eye icon in front of the QMask From the channel dialog you can double click on the name or the thumbnail to edit the QMask attributes Then you can changethe Opacity and its filling color Once a quick mask is initialized click on it to be sure it is selected and blue highlighted in the list and start to paint on it with any Gimp paint tool The mask is coded in gray tones so you must use white or gray to decrease the area limited by the mask and black to increase it The area painted in light or dark gray will be transition areas for the selection like feathering When your mask is ready click again on the bottom left GNU Image Manipulation Program Page 159 of 421 Generated by docbook2odf xe O N E O O 2 S O xe a 2 xe o G d 3 S o button in the image window and the quick maskwill be removed from the channel list and converted to aselection Quick mask s purpose is to paint a selection and its transitions with the paint tools without worrying about managing selection masks
211. eas and white color to add selected areas You can use grey colors to get partially selected areas You can also use selection tools and fill these selections with the Bucket Fill tool This does not destroy the Qmask selections Toggle off the Quickmask using the left bottom button in the image window the selection will be displayed with its marching ants GNU Image Manipulation Program Page 64 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Creating New Layers There are several ways to create new layers in an image Here are the most important ones e Selecting Layer New Layer in the image menu This brings up a dialog that allows you to set the basic properties of the new layer see the New Layer dialog section for help with it e Selecting Layer Duplicate Layer in the image menu This creates a new layer that is a perfect copy of the currently active layer just above the active layer e When you cut or copy something and then paste it using Ctrl V or Edit Paste the result is a floating selection which is a sort of temporary layer Before you can do anything else you either have to anchor the floating selection to an existing layer or convert it into a normal layer If you do the latter the new layer will be sized just large enough to contain the pasted material pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o GNU Image M
212. ecise selections Key modifiers e Ctrl Holding down the Ctrl key has a special effect on every brush tool except the ink tool For the Pencil Paintbrush Airbrush Eraser and Smudge tools it switches them into color picker mode so that clicking on an image pixel causes GIMP s foreground to be set to the active layer s color at that point or for the Eraser GIMP s background color For the Clone tool the Ctrl key switches it into a mode where clicking sets the reference point for copying For the Convolve tool the Ctrl key switches between blur and sharpen modes the the Dodge Burn tool it switches between dodging and burning GNU Image Manipulation Program Page 115 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o e Straight Line Shift Holding down the Shift key has the same effect on all brush tools it places the tool into straight line mode To create a straight line with any of the brush tools first click on the starting point then press the Shift key As long as you hold it down you will see a thin line connecting the previously clicked point with the current pointer location If you click again while continuing to hold down the Shift key a Straight line will be rendered You can continue this process to create a series of connected line segments e Ctrl Shift Holding down both keys puts the tool into constrained straight line mode This is similar to the
213. ed by you should be placed The system folder should not be marked as writable and you should not try to alter its contents The personal folder must be marked as writable or it is useless because there is nothing inside it except what you put there You can customize the search path with the buttons at the top of the dialog Device Status dialog pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 200 of 421 Generated by docbook2odf Device Status H Core Pointer i Eai i o This window gathers together the current options of Toolbox for each of your input devices the mouse named Core pointer or either the tablet if you have one These options are represented by icons foreground and background colors brush pattern and gradient Excepted for colors clicking on an icon opens the window which lets you select another option the tool box will be updated when changing In addition you can add tabs and other dialog by click and drag The Record device status button at the bottom of the window seems to have the same action as the Record device status now option in the Input Devices section in preferences Activate Dialog You will find this dialog in the Toolbox menu bar through File Dialogs Device Status Error Console The Error console offers more possibilities than the single GIMP Message This is a log of all errors occuring while GIMP is running
214. ed to define the type of image on which we work Registering The Script s Parameters Once we have listed the required parameters we then need to list the parameters that correspond to the parameters our script needs When we list these params we give hints as to what their types are This is for the dialog which pops up when the user selects our script We also provide a default value This section of the registration process has the following format GNU Image Manipulation Program Page 92 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o SF VALUE Accepts numbers and strings Note that quotes must be escaped for default text so better use SF STRING SF COLOR Indicates that a color is O 102 255 requested in this parameter SF TOGGLE A checkbox is displayed to TRUE or FALSE get a Boolean value SF IMAGE If your script operates on an open image this should be the first parameter after the required parameters Gimp will pass in a reference to the image in this parameter SF DRAWABLE If your script operates on an open image this should be the second parameter after the SF IMAGE param It refers to the active layer Gimp will pass in a reference to the active layer in this parameter Giving Our Script Some Guts Let us continue with our training and add some functionality to our script Creating A New Image In the previous lesson we created
215. ee view tab If you still don t find finally explore the menus or look at the source code in the Register section whichever is easiest For more complex plugins organized as a directory with multiple files there ought to be a file inside called either INSTALL or README with instructions If not the best advice is to toss the plugin in the trash and spend your time on something else any code written with So little concern for the user Is likely to be frustrating In myriad ways Some plugins specifically those based on the GIMP Plugin Template are designed to be GNU Image Manipulation Program Page 46 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o installed in the main system GIMP directory rather than your home directory For these you will need to be root to perform the final stage of installation when issuing the make install command If you Install in your personal plugin directory a plugin that has the same name as one In the system plugin directory only one can be loaded and it will be the one in your home directory You will receive messages telling you this each time you start GIMP This is probably a situation best avoided Windows Windows is a much more problematic environment for building software than Linux Every decent Linux distribution comes fully supplied with tools for compiling software and they are all very similar in the way they work but
216. egrees The Rotate 180 degrees command rotates the active layer by 180 around the center of the layer with no loss of pixel data The shape of the layer is not altered but the rotation may cause the layer to extend beyond the bounds of the image This is allowed in GIMP and it does not mean that the layer is cropped However you will not be able to see the parts which extend beyond the boundary of the image unless you resize the image canvas or move the layer Activating the Command e You can access this command from the image menubar through Layer Transform Rotate 180 degrees GNU Image Manipulation Program Page 278 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Arbitrary Rotation The Arbitrary Rotation command rotates a layer by a specified angle It is an alternate way of accessing the Rotate tool See the section about that tool for more information Activating the Command e You can access this command from the image menubar through Layer Transform Arbitrary Rotation e or by using the keyboard shortcut Shift R Offset The Offset command shifts the contents of the active layer Anything shifted outside the layer boundary is cropped This command displays a dialog which allows you to specify how much to shift the layer and how to fill the space that is left empty by shifting it Activating the Command e You can access this command from the image menub
217. emplates dialog to modify or delete templates Activating the Command e You can access this command from the tmage menubar through File Save as GNU Image Manipulation Program Page 219 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Template There is no default keyboard shortcut Revert The Revert command reloads the image from disk so that it looks just like it did the last time it was saved unless that is you or some application other than GIMP have modifed the image file in which case the new contents are loaded When GIMP reverts a file it actually closes the existing image and creates a new image Because of this reverting an image Is not undoable and causes the undo history of the image to be lost GIMP tries to protect you from losing your work in this way by asking you to confirm that you really want to revert the image Activating the Command e You can access this command from the image menubar through File Revert There is no default keyboard shortcut Print The Print command is not really part of GIMP It simply calls the printing interface of your operating system to set the printer options Activating the Command You can access this command from the image menubar through File Print Close The Close command closes the image and removes its window Closing an image is not undoable once it is closed everything is gone including the u
218. eneral purpose but rather limited vector graphics tool Plasma Parameter Settings Random Seed 1890462285 B New Seed i Randomize Turbulence 2 9 B Overview You can find this filter in image menu following Filters Render Clouds Plasma Plasma generates colorful clouds which can be used for textures You control the turbulence in the plasma cloud with the Turbulence slide All of the colors produced by Plasma are completely saturated Sometimes the strong GNU Image Manipulation Program Page 382 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 v o ww hn o c o colors may be distracting and a more interesting surface will appear when you desaturate the image using Layer Colors Desaturate An enhanced version of the Plasma plug in called Plasma2 with many more options and parameters is available from the Gimp Plugin Registry Options Solid Noise Parameter Settings Random Seed 628992469 g New Seed W Randomize Turbulent Detail 2 B l Tilable X Size EE De 4 0 B Y Size a ao Overview You can find this filter from the image menu through Filters Render Clouds Solid noise Solid Noise is a great texture maker Note that this noise is always gray even if you applied it to a very colorful image it doesn t matter what the original image looks like this filter completely overwrites any existing background in the layer it is applied to
219. enerated by docbook2odf General Use Dot for dot by default Marching ants speed 300 Zoom amp Resize Behavior Resize window on zoom A Resize window on image size change Initial zoom ratio Fit to window Mouse Cursors Show brush outline Cursor mode Cursor rendering Options Image Window Appearance GNU Image Manipulation Program Generated by docbook2odf Page 191 of 421 pe O N E O O 2 S O xe a 2 xe o d 3 S o Image Window Appearance Default Appearance in Normal Mode m Show menubar jv Show selection ff Show rulers ff Show layer boundary Jv Show scrollbars Show guides ff Show statusbar Show grid Canvas padding mode From theme Custom padding color Default Appearance in Fullscreen Mode Show menubar Show selection Show rulers Show layer boundary Show scrollbars Show guides Show statusbar Show grid Canvas padding mode Custom color Custom padding color a The only parts that may need further explanation are the ones related to padding Padding is the color shown around the edges of the image if it does not occupy all of the display area Shown in light gray in all the figures here You can choose among four colors for the padding color to use the color specified by the current theme to use the light or dark colors specified for checks such as represent transparent parts of the image
220. ent pixel to that average value Filter advantage Is its calculation speed It suits big images Filter disadvantage is that its action is hardly perceptible on big images but very strong on small images Activate the filter This filter can be called from the image menu Filters Blur Blur Gaussian Blur Overview ce na j aie LoL Tee Lo ke e N xX e e 2 o e ke gt 2 3 0 Ww hn o GNU Image Manipulation Program Page 290 of 421 Generated by docbook2odf You can find this filter in the image menu under Filters Blur Gaussian Blur The IIR Gaussian Blur plug in acts on each pixel of the active layer or selection setting its Value to the average of all pixel Values present in a radius defined in the dialog A higher Value will produce a higher amount of blur The blur can be set to act in one direction more than the other by clicking the Chain Button so that it is broken and altering the radius GIMP supports two implementations of Gaussian Blur IIR G B and RLE G B They both produce the same results but each one can be faster in some cases Options Blur Radius Blur Method Horizontal so IIR fif i o jo RU Vertical 5 0 px A RLE l Selective Gaussian Blur Overview GNU Image Manipulation Program Page 291 of 421 Generated by docbook2odf o l 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o You can find this filter in the
221. enu This dialog provides the most commonly used methods for altering the colormap for an indexed image The color tools such as Brightness Contrast Hue Saturation etc do not operate on indexed images There are a few plug ins that do so including the Normalize Color Enhance and Stretch Contrast operations and it is possible to create others as well Histogram dialog Histogram x Background cbs Value Se _ j pss FI Mean 186 8 Pixels 1463200 Std Dev 44 3 Count 1483200 Median 182 0 Percentile 100 0 GNU Image Manipulation Program Page 163 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 v o ww in o c o The Histogram dialog shows you information about the statistical distribution of color values in the image that Is currently active This information is often useful when you are trying to color balance an image However the Histogram dialog is purely informational nothing you do with it will cause any change to the image If you want to perform a histogram based color correction use the Levels tool Dialog call This is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in two ways e From the Toolbox menu File Dialogs Histogram e From the image menu Dialogs Histogram About Histograms In GIMP each layer of an i
222. enubar through Layer Stack Select Previous Layer e or by using the keyboard shortcut Page Up e or the Up arrow key e or simply by clicking on the layer name in the Layers Dialog Select Next Layer The Select Next Layer command selects the layer just underneath the active layer in the layer stack The command highlights the layer in the Layers Dialog and makes it the new active layer If the active layer is already at the bottom of the stack this menu entry is Insensitive and grayed out Note that on a standard Windows style English keyboard the default shortcut Page Down does not refer to the key on the numeric keypad but to the other Page Down key in the group of six keys to the left of the numeric keypad Activating the Command e You can access this command from the image menubar through Layer Stack Select Next Layer e or by using the keyboard shortcut Page Down e or the Down arrow key e or simply by clicking on the layer name in Layers Dialog Select Top Layer The Select Top Layer command makes the top layer in the stack the active layer for the image and highlights it in the Layers dialog If the active layer is already the top layer in the stack this menu entry is insensitive and grayed out Note that on a standard Windows style English keyboard the default keyboard shortcut Home does not refer to the key on the numeric keypad but to the other Home key in the group of six keys to the left of the numeric keypa
223. ers box is checked Choose HSV and click OK You will get a new grey level image with three layers one for Hue one for Saturation and one for Value Close the original image so you won t get confused Select the Value layer and apply your sharpening to it When you are done with that same layer selected reverse the process Go to Image Mode and click on Compose Again choose HSV and click OK You will get back your original image except that it will have been sharpened in the Value component pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 332 of 421 Generated by docbook2odf Generic filters Generic filters introduction Generic filters are filters you can build your own filters with That looks complicated See Convolution Matrix filter and you will understand better Convolution matrix Matrix Border p 00c 0 004 0 004 0 004 0 004 Extend C Wrap 0 00 0 00 0 00 0 00 0 004 Crop 0 00 0 00 1 00 0 00 0 004 Channels 0 00c 0 00c 0 00c 0 00c o 00 C Grey 0 00 0 004 o 00c 0 004 0 000 M Red m Green Divisor 1 00 Offset 0 004 7 Blue l Automatic Alpha 7 Alpha weighting sJ Reset Cancel Pox Overview You can find this filter via the image menu under Filters Generic Convolution Matrix Here is a mathematician s domain Most of filters are using convolution matrix With the Convolution Matrix filter
224. erview pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 313 of 421 Generated by docbook2odf This tool offers you a collection of unified filters to treat the image Of course same functions can be performed by particular filters but you have here an interesting Intuitive overview Starting filter This filter is found in the image menu via Filters Colors Filter Pack Options Before and After Original Current Show Windows Entire Image Hue Selection Only _ Saturation Selection In Context Value Affected Range Advanced Shadows Midtones Highlights Select Pixels by Hue Saturation Reset a Cancel Pox GNU Image Manipulation Program Page 314 of 421 Generated by docbook2odf o l 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o Hot Reduce Luminance Reduce Saturation Blacken Cancel Overview This filter is found in the image menu via Filters Colors Hot It identifies and modifies pixels which might cause problem when displayed onto PAL or NTSC TV screen Options Max RGB Hold the Minimal Channels z e E N Overview x e 2 o e ke gt 2 3 0 c o GNU Image Manipulation Program Page 315 of 421 Generated by docbook2odf This filter is found in the image menu via Filters Colors Max RGB For every pixel of
225. es TH Heel Click The scrolled window of the Module Manager shows the loadable modules You can click on the boxes in the Autoload column to check or uncheck them The directory path for each module is shown in the Module path column Information about the selected module is displayed at the bottom of the dialog The Unit Editor The Unit Editor command displays a dialog which shows information about the units of measurement that are currently being used by GIMP It also allows you to create new units which can be used by GIMP in a variety of situations Activating the Command e You can access this command from the toolbox menubar through Xtns Unit Editor gt Description of the Unit Editor dialog window nmt Enma Dualrate Saved IDs Fal Digis Symbo Abbievia ont Sirgu ar inzhzs LUVOUOU 2 g i inch m llireleis 25 400070 mil ire er ru lin lers po nts f2 000000 poinz points picas 6 0007200 pica picas rentimeters P G400OT F centimeter centimeters mitem U0 25400 mete Melcrs leel 0 083333 fool el vards O 027 2 76 l werd yards typog prints 72 272000 3 pt tyiogr point typogr po nts typagro peas 077500 tyoogr pica Pypogr pitas Hzlp Retresh y ae O N E O e 2 S O xe a 2 ae o 4 d 3 S o GNU Image Manipulation Program Page 209 of 421 Generated by docbook2odf The figure above shows the Unit Editor dialog window The list shows the units of measurement whi
226. es Four of them the Pencil Paintbrush Airbrush and Ink tools behave like the intuitive notion of painting with a brush The others use a brush to modify an image in some way rather than paint on it the Eraser erases the Clone tool copies from a pattern or image the Convolve tool blurs or sharpens the Dodge Burn tool lightens or darkens and the Smudge tool smears The advantages of using GIMP with a tablet instead of a mouse probably show up more clearly for brush tools than anywhere else the gain is fine control is invaluable These tools also have special Pressure sensitivity options that are only usable with a tablet In addition to the more common hands on method it is possible to apply brush tools in an automated way by creating a selection or path and then stroking it You can choose to stroke with any of the brush tools including nonstandard ones such as the Eraser Smudge tool etc and any options you set for the tool will be applied See the section on Stroking for more information Brush tools work not only on image layers but on other types of drawable objects as well layer masks channels and the selection To apply a brush tool to a layer mask or channel simply make it the image s active drawable by clicking on it in the Layers dialog or Channels dialog To apply a brush tool to the selection switch to QuickMask mode Painting the selection in this way is a very powerful method for efficiently creating pr
227. es that affect all selection tools in the same way See Selection Tools for help with these Options GNU Image Manipulation Program Page 111 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Fuzzy Select vode AMH E E Z Antialiasing Feather edges Radus m 10 0 Finding Similar Colors F Select transparent areas Sample merged Threshold _ 15 0 _ amp 3 See Selection Tools for help with options that are common to all these tools Only options that are specific to the Magic Wand tool are explained here Select By Color Tool 5 The Select by Color tool is designed to select areas of an image based on color similarity It works a lot like the Fuzzy Select tool Magic Wand The main difference between them is that the Magic Wand selects contiguous regions with all parts connected to the starting point by paths containing no large gaps while the Select by Color tool selects all pixels that are sufficiently similar in color to the pixel you click on regardless of where they are located Also clicking and dragging in the image has no effect on the Select by Color tool How to Activate he Select By Color Tool can be activated from an image menu as Tools Selection ools Select by Color from the Toolbox by clicking on the tool icon or from the keyboard using the shortcut Shift CtriC Key modifiers Defaults The select by color tool
228. ess this command from the image menu bar through Image Mode Indexed The Convert Image to Indexed Colors dialog The Indexed command opens the Convert Image to Indexed Colors dialog General Palette Options Use Black and White 1 Bit Palette Use Custom Palette Web f Remove Unused Colors from Final Palette Dithering Options No Color Dithering Floyd Steinberg Color Dithering Normal Floyd Steinberg Color Dithering Reduced Color Bleeding Positioned Color Dithering l Enable Dithering of Transparency Warning You are attempting to convert an image with an alpha channel to indexed colors Do not generate a palette of more than 255 colors if you intend to create a transparent or animated GIF file Af Cancel You can edit the color palette of an indexed image by using the Colormap Dialog Decompose With the Decompose command you can decompose an image into its color components You can find more information about using this command in the Decompose filter section Activating the Command e You can access this command from the image menubar through Image Mode Decompose Compose With the Compose command you can re compose an image that has been decomposed GNU Image Manipulation Program Page 248 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o into its color components You can find more information about using this com
229. ffer e Paste Buffer Into This command pastes the contents of the selected buffer into the active image s selection as a floating selection The only difference between this and the ordinary Paste Into command is that it uses the selected buffer rather than the global clipboard buffer e Paste Buffer as New This command creates a new single layer image out of the contents of the selected buffer The only difference between this and the ordinary Paste as New command is that it uses the selected buffer rather than the global clipboard buffer e Delete Buffer This command deletes the selected named buffer no questions asked You cannot delete the Global Buffer You can change the size of the buffer previews in the dialog using the Preview Size submenu of the dialog s Tab menu Images dialog The Images Dialog displays the list of open images on your screen each of them is represented with a thumbnail This dialog is useful when you have many overlapping images on your screen thus you can raise the wanted image to foreground GNU Image Manipulation Program Page 178 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o G d 9 S o The Images dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in several ways e From the Toolbox menu File Dialogs Images e From an image menu Dialogs Images e From the Tab
230. ffsets and colors of the grid lines can all be set by the user By default the lines are with the Gimp s foreground color Note this plugin was used to create GNU Image Manipulation Program Page 390 of 421 Generated by docbook2odf xe O N E O O 2 S O xe a 2 xo 4 G d 3 S o demonstration images for many of the other plugins If you set the grid line widths to O then only the intersections will be drawn as plus marks Options There are separate options for controlling the horizontal grid lines vertical grid lines and intersections By default the horizontal and vertical settings are locked together so that all changes are applied symmetrically If you want to change just one of them click on the chain symbol below it to unlock them The results of changing the intersection parameters are rather complex Besides for some options you can select the unit of measurement thanks to a drop down list Maze Parameter Settings Width Pixels 5 Pieces d 51 b Height Pixels 5 Pieces 4 51 p Tileable 2777356031 ef eed Randomize Style Depth First C Prims Algorithm Selection is 256x256 Dur TIRTS Overview GNU Image Manipulation Program Page 391 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o You can find this filter in image menu following Filters Render Pattern Maze This filter genera
231. find descriptions of their capabilities in the documentation for the extensions The Module Manager With the Module Manager command you can show the various extension modules which are available and control which of them should be loaded Modules perform functions such as choosing colors and display filtering Any changes you make to the settings with the Module Manager command will take effect the next time you start GIMP These changes affect GIMP s functional capabilities its size in memory and its startup time Activating the Command e You can access this command from the toolbox menubar through Xtns Module Manager Description of the Module Manager Dialog GNU Image Manipulation Program Page 208 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o AAE E ATANI PE anbara Bounds aab A hap onines led sceay es eke bitin sa Siwy meer les bcdsaty gacma sa ML isipo mnes las eia igberi ala risaqmi adels bedsacy aehss Seine HHEN HERTE ET E ETE irg mei eles bes ariel trirght sa Bi iaie ites Tle sea ees AIM MeL eles besvrsis Irox puke Ang bo ened hee icles hen Moar pune Do che ed sre ula kei Der ee be dies Aiken age md ANPA menaz Hytowr erkei ginp arg Soo Saugrery anarvschocacats Rox Wigds Sacer scbicacace WHOM ED etl Copy Ml S002 200 seltased Leder the GFL l4 H Janay a As Larckar an ds hla we Hee eo Last rvar Avalakle ypes F lyoss Fea
232. format whose specification is available to the general public that is suitable for revisingthe document straightforwardly with generic text editors or for images composed of pixels generic paint programs or for drawings some widely available drawing editor and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters A copy made in an otherwise Transparent file format whose markup or absence of markup has been arranged to thwart or discourage Subsequent modification by readers is not Transparent An image format is not Transparent if used for any substantial amount of text A copy that is not Transparent is called Opaque Examples of suitable formats for Transparent copies include plain ASCII without markup Texinfo input format LaTeX input format SGML or XML using a publicly available DTD and standard conforming simple HTML PostScript or PDF designed for human modification Examples of transparent image formats include PNG XCF and JPG Opaque formats include proprietary formats that can be read and edited only by proprietary word processors SGML or XML for which the DTD and or processing tools are not generally available and the machine generated HTML PostScript or PDF produced by some word processors for output purposes only The Title Page means for a printed book the title page itself plus such following pages as are needed to hold legibly the m
233. g out the maximum amount of detail across all areas of an image Duplicate the layer producing a new layer above it Desaturate the new layer Apply a Gaussian blur to the result with a large radius 100 or more Set Mode in the Layers dialog to Divide Control the amount of correction by adjusting opacity in the Layers dialog or by using Brightness Contrast Levels or Curves tools on the new layer When you are happy with the result you can use Merge Down to combine the control layer and the original layer into a single layer In addition to Multiply and Divide you may every so often get useful effects with other layer combination modes such as Dodge Burn or Soft Light It is all too easy though once you start playing with these things to look away from the computer for a moment and suddenly find that you have just spent an hour twiddling parameters Be warned the more options you have the harder it is to make a decision Adjusting Hue and Saturation In our experience if your image has a color cast too much red too much blue etc the easiest way to correct it is to use the Levels tool adjusting levels individually on the red green and blue channels If this doesn t work for you it might be worth your while to try the Color Balance tool or the Curves tool but these are much more difficult to use effectively They are very good for creating certain types of special effects though Sometimes it is hard
234. ge 245 of 421 Generated by docbook2odf The Image Menu of the Image Window The Image Menu of the Image Window CI Duplicate Mode Transform A Crop Image Autocrop Image fealous Crop Merge Visible Layers Ctrl M Flatten Image H Configure Grid The Image menu contains commands which use or affect the entire image in some way not just the active layer or some other specific part of the image You may find other commands in the menu besides the ones described here These commands are not part of The GIMP itself but are added by some of the plug ins Please refer to the documentation on the extensions for more information about these menu commands Duplicate The Duplicate image command creates a new image which is an exact copy of the current one with all of its layers channels and paths The GIMP Clipboard and the History are not affected Activating the command e You can access this command from the image menu through Image Duplicate e or by using the keyboard shortcut Ctrl D Mode GNU Image Manipulation Program Page 246 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o atti Layer my Duplicate Ctrl D Transform d E Grayscale ae Indexed At Canvas to Layers Compose Print Size CEE 2 Crop Image Autocrop Image Zealous Crop Merge Visible Layers Ctrl M Flatten Image Guides HH Contigure Grid Separat
235. ge menu through Filters Map Fractal trace Sen Options 5 e N xX e e 2 o e ke gt 2 3 0 Ww hn o GNU Image Manipulation Program Page 372 of 421 Generated by docbook2odf Outside Type Warp O Transparent Black O White Mandelbrot Parameters xi km ho Depth daa 3 B Illusion Overview This filter is found in the image window menu under Filters Map Illusion With this filter your image active layer or selection looks like a kaleidoscope This filter duplicates your image in many copies more or less dimmed and split and puts them around center of image Options X Preview Divisions a B Mode 1 Mode 2 Make Seamless Overview GNU Image Manipulation Program Page 373 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 9 S o You can find this filter in image menu under Filters Map Make Seamless This filter modifies the image for tiling by creating seamless edges Such an image can be used as a pattern for a web page This filter has no option and result may need correction Map Object Overview This filter maps a picture to an object plane sphere box or cylinder This filter is found in the image window menu under Filters Map Map Oject Preview domain This preview has several possibilities General Options tab Options Light M aterial Orientation
236. ge of the Preferences dialog The next thing to do is to see how much resources you require for other apps you want to run at the same time than GIMP So start all your tools and do some work with them except GIMP of course and check the usage You can use applications like free or top depending in what OS and what environment you use The numbers you want is the memory left including file cache Modern Unix keeps a very small area free in order to be able to keep large file and buffer caches Linux s free command does the maths for you check the column that says free and the line buffers cache Note down also the free swap Now time for decisions and a bit of simple math Basically the concept Is to decide if you want to base all Tile Cache in RAM or RAM plus operating system swap Do you change applications a lot Or keep working in GIMP for a long time If you spend a lot of time in GIMP you can consider free RAM plus free swap as available if not you need to go to the following steps If you re feeling unsure about it check the following steps If you are sure you switch apps every few minutes only count the free RAM and GNU Image Manipulation Program Page 61 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o just go to the final decision no more things to check Does the operating system swap live in the same physical disk as GIMP swap If so add RAM a
237. h an eye Please note that the information about the layers is lost when the image data is put in the clipboard When you later paste the clipboard contents there is only one layer which is the fusion of all the marked layers Activating the Command e You can access this command from the image menubar through Edit Copy Visible Paste The Paste command puts whatever is in the Clipboard from the last Copy or Cut command into the current image The pasted section becomes a floating selection and is shown as a separate layer in the Layers Dialog If there is an existing selection on the canvas it is used to align the pasted data If there is already a selection the data Is pasted using the selection as a center point If you want the selection to be used as a clipping region for the pasted data you should use the Paste Into command You can have only one floating selection at any one time You cannot work on any other layer while there is a floating selection you have to either anchor it or remove it Activating the Command e You can access this command from the image menubar through Edit Paste e or by using the keyboard shortcut Ctrl V Paste Into The Paste Into command acts in a similar way to the Paste command The primary difference becomes apparent if there is a selection within the canvas Unlike the Paste command which simply centers the pasted image data over the selection and replaces the selection with tts o
238. h as erasing copying smudging lightening or darkening etc All of the paint tools except the ink tool use the same set of brushes The brush pixmaps represent the marks that are made by single touches of the brush to the image A brush stroke usually made by moving the pointer across the image with the mouse button held down produces a series of marks spaced along the trajectory in a way specified by the characteristics of the brush and the paint tool being used Brushes can be selected by clicking on an icon in the Brushes dialog GIMP s current brush is shown in the Brush Pattern Gradient area of the Toolbox Clicking on the brush symbol there is one way of activating the Brushes dialog When you install GIMP it comes presupplied with a number of basic brushes plus a few bizarre ones that serve mainly to give you examples of what is possible i e the green pepper brush in the illustration You can also create new brushes or download them and install them so that GIMP will recognize them GIMP can use several different types of brushes All of them however are used in the Same way and for most purposes you don t need to be aware of the differences when you paint with them Here are the available types of brushes One category that GIMP does not have is full fledged procedural brushes brushes whose marks are calculated procedurally instead of being taken from a fixed pixmap Actually this is not quite correct the Ink tool u
239. h gray to white the colors with the largest portion red orange yellow green blue violet or other pure colors that lie between them and the saturation of the colors gaudy to pale This color model is based on the ability of the eye to recognize small differences in lunminosity better than small color differences and to recognize those better than small differences in saturation That makes gray text written on a black background easy to read but blue text on a red background very hard to read even with the same basic brightness Such color models are called brightness color models The YCbCr model is a slight adaptation of such a brightness color model An RBG color value is divided into a basic brightness Y and two components Cb and Cr where Cb is a measurement of the deviation from gray in the blue direction or if it is less that 0 5 in the direction of yellow Cr is the corresponding measurement for the difference in the direction of red or turquoise This representation uses the peculiarity of the eye of being especially sensitive to green light That is why most of the information about the proportion of green is in the basic brightness Y an only the deviations for the red and blue portions need to be represented The Y values have twice the resolution of the other two values Cb and Cr in most practical applications such as on DVDs The YUV color model uses two components to represent the color information luma the s
240. h new revised versions of the GNU Free Documentation License from time to time Such new versions will be similar in spirit to the present version but may differ in detail to address new problems or concerns See http www gnu org copyleft Each version of the License is given a distinguishing version number If the Document specifies that a particular numbered version of this License or any later version applies to it you have the option of following the terms and conditions either of that specified version or of any later version that has been published not as a draft by the Free Software Foundation If the Document does not specify a version number of this License you may choose any version ever published not as a draft by the Free Software Foundation To use this License in a document you have written include a copy of the License in the document and put the following copyrightand license notices just after the title page Copyright c YEAR YOUR NAME Permission is granted to copy distribute and or modify this document under the terms of the GNU Free Documentation License Version 1 2 or any later version published by the Free Software Foundation with no Invariant Sections no Front Cover Texts and no Back Cover Texts A copy of the license is included in the section entitled GNU Free Documentation License If you have Invariant Sections Front Cover Texts and Back Cover Texts replace the with Texts line with this G
241. hannel to it Activating the Command e You can access this command from the image menubar through Layer Stack Raise Layer e or by clicking on the up arrow icon at the bottom of the Layers dialog Lower Layer The Lower layer command lowers the active layer one position in the layer stack If the active layer is already at the bottom of the stack or if there is only one layer this menu entry Is insensitive and grayed out Activating the Command e You can access this command from the image menubar through Layer Stack Lower Layer e or by clicking on the down arrow icon at the bottom of the Layers dialog Layer to Top The Layer to Top command raises the active layer to the top of the layer stack If the active layer is already at the top or if there is only one layer this menu entry is insensitive and grayed out If the active layer is at the bottom of the stack and it does not have an alpha channel you cannot raise it until you add an alpha channel to it Activating the Command e You can access this command from the image menubar through Layer Stack Layer to Top e or by pressing the Shift key and clicking on the up arrow icon at the bottom of the Layers dialog GNU Image Manipulation Program Page 263 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Layer to Bottom The Layer to bottom command lowers the active layer to the bottom of the layer stack If
242. have color variations extending into the border zone of the active layer they are cropped away Activating the Command e You can access this command from the image menubar through Image Autocrop Image Zealous Crop The Zealous Crop command crops an image using a single solid color as a guide It crops the edges as with the Autocrop command but it also crops the areas in the middle of the image which have the same color at least in principle Please note that Autocrop crops all of the layers although it only analyzes the active layer This may lead to a loss of information from the other layers GNU Image Manipulation Program Page 253 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Example Activating the Command e You can access this command from the image menubar through Image Zealous Crop Merge Visible Layers The Merge Visible Layers command merges the layers which are visible into a single layer Visible layers are those which are indicated on the Layers dialog with an eye icon Activating the Command e You can access this command from the image menubar through Image Merge Visible Layers e or by using the keyboard shortcut Ctrl M Description of the Merge Visible Layers Dialog o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 254 of 421 Generated by docbook2odf F
243. he eye icons that appear on the left side of each row in List mode In particular if you use the Color tools a lot you may benefit from toggling visibility on for them here You can also change the order of tools in the Toolbox by clicking on an item in the Tools dialog in List mode and dragging it up or down in the list If you screw things up you can always press the Reset button at the bottom of the dialog to restore the defaults for GNU Image Manipulation Program Page 182 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o order and visibility Right clicking inside the dialog produces the Tools menu which gives you an alternative way of toggling visibility or restoring the defaults Preferences Introduction New Image aa Detault Grid oe Interface ag Theme H Help System ae Tool Options FS Toolbox z7 Image Windows Appearance Title amp Status Display a Ti Input Devices Input Controllers CA Window Management B Environment ga amp Folders a Brushes SD Patterns tmi Palettes Gradients an Fonts Plug Ins scripts Modules gt Environment Gp Themes The preferences dialog can be accessed from the Toolbox menu as File Preferences It lets you customize many aspects of the way GIMP works The following sections detail the settings that you can customize and what they affect This information applies Specifically to Gimp 2 2 but t
244. he new layer Activating the Command e You can access this command from the image menubar through Layer New Layer Description of the New Layer Dialog GNU Image Manipulation Program Page 259 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Create a New Layer Untitled 1 Layer Name pte ae Width 377 Height 233 Layer Fill Type C Foreground color Background color C White Transparency Duplicate layer The Duplicate Layer command adds a new layer to the image which is a nearly identical copy of the active layer The name of the new layer is the same as the name of the original layer but with copy appended to it If you duplicate a background layer which does not have an alpha channel the new layer IS provided with one In addition if there are any parasites attached to the active layer they are not duplicated If your understanding of the word parasites is limited to small unpleasant creatures please ignore the last sentence Activating the Command e You can access this command from the image menubar through Layer Duplicate Layer Anchor layer When you move or paste a selection a temporary layer called a floating layer or floating selection is added to the layer stack As long as the floating layer persists you can work only on it To work on the rest of the image you must anchor the floating layer to the former active
245. he part of the initial layer corresponding to this cleared area Is also transparent GNU Image Manipulation Program Page 351 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Options Example Polar Coords Parameter Settings Circle Depth in Percent it 100 00 Offset Angle _1 7 o oo E ff Map from Top W To Polar a Cancel Overview This filter is found in Filters Distorts Polar Coords It gives a circular or a rectangular representation of your image with all the possible intermediates between both Options Examples THE GIMP GNU Image Manipulation Program Page 352 of 421 Generated by docbook2odf y xe O N E O O 2 S O xe a 2 xe o G d 3 S o Ripple Orientation Horizontal O Vertical Wave Type Sawtooth f Sine Parameter Settings Period E 20 g Amplitude L 5 X Cancel Overview This filter is found in Image gt Filters Distorts Rippel It displaces the pixels of the active layer or selection to waves or ripples reminding a reflection on disturbed water Options Shift Parameter Settings C Shift Vertically Shift Amount 5 B px Overview This filter is found in Filters Distorts Sift It shifts all pixel rows horizontally or vertically in the current layer or selection ona random distance and within determined limits GNU Image Manipulation Progra
246. he path that the tool finds will correspond to the contour you are trying to select Each time you left click with the mouse you create a new control point which is connected to the last control point by a curve that tries to follow edges in the image To finish click on the first point the cursor changes to indicate when you are in the right Spot You can adjust the curve by dragging the control nodes or by clicking to create new control nodes When you are satisfied click anywhere inside the curve to convert it into a selection Be sure not to click inside the curve until you are completely done adjusting it Once you have converted it into a selection undoing takes you back to zero and you will have to to start constructing the curve again from scratch if you need to change it Also be sure not GNU Image Manipulation Program Page 113 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o to switch to a different tool or again all of your carefully created control nodes will be lost But you still can transform your selection into a path and work it with the Path tool Unfortunately there seem to be some problems with the edge following logic for this tool with the result that the selections it creates tend to be pretty crude in a lot of cases A good way to clean them up is to switch to QuickMask mode and use paint tools to paint in the problematic parts On the whole mo
247. he reading or further copying of the copies you make or distribute However you may accept compensation in exchange for copies If you distribute a large enough number of copies you must also follow the conditions tn sections You may also lend copies under the same conditions stated above and you may publicly display copies If you publish printed copies or copies in media that commonly have printed covers of the Document numbering more than 100 and the Document s license notice requires Cover Texts you must enclose the copies in covers that carry clearly and legibly all these Cover Texts Front Cover Texts on the front cover and Back Cover Texts on the back cover Both covers must also clearly and legibly identify you as the publisher of these copies The front cover must present the full title with all words of the title equally prominent and visible You may add other material on the covers in addition Copying with changes limited to the covers as long as they preserve the title of the Document and satisfy these conditions can be treated as verbatim copying in other respects If the required texts for either cover are too voluminous to fit legibly you should put the GNU Image Manipulation Program Page 417 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 hn 0 S o first ones listed as many as fit reasonably on the actual cover and continue the rest onto adjacent pages
248. he selection into a path without losing information In fact any information about partially selected areas i e feathering will be lost when the selection is turned into a path If the path is transformed back into a selection the result is an all or none selection similar to what would be obtained by executing Sharpen from the Select menu Paths and Text GNU Image Manipulation Program Page 32 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o A text item created using the Text tool can be transformed into a path using the Create path from text button in the Tool Options for the Text tool This can be useful for several purposes including e Stroking the path which gives you many possibilities for fancy text e More importantly transforming the text Converting text into a path then transforming the path and finally either stroking the path or converting it to a selection and filling it often leads to much higher quality results than rendering the text as a layer and transforming the pixel data Paths and SVG files SVG standing for Scalable Vector Graphics is an increasingly popular file format for vector graphics in which graphical elements are represented in a resolution independent format in contrast to raster graphics in which graphical elements are represented as arrays of pixels GIMP is mainly a raster graphics program but paths are vector entit
249. he settings for Gimp 2 0 are similar enough that you should be able to understand them based on the explanations here All of the Preferences information is stored in a file called gimprc in your personal GIMP directory so if you are a power user who would rather work with a text editor than a graphical interface you can alter preferences by editing that file If you do and you are on a Linux system then man gimprc will give you a lot of technical information about the contents of the file and what they are used for New Image Preferences GNU Image Manipulation Program Page 183 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Template Width 377 Height 233 f pixels e a Advanced Options X resolution 72 000 I Y resolution 72 000 F pixels in H Colorspace RGB color Ra Fill with Background color Comment Created with The GIMP This tab lets you customize the default settings for the New Image dialog See the New Image Dialog section for an explanation of what each of the values means Default Image Grid pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 184 of 421 Generated by docbook2odf Default Image Grid Appearance Line Style Intersections crosshairs Foreground color EE Background color Spacing Width Height o Ejo EP 0 139 l 0 139
250. hitt G S Frequency G S Phaseshift B L Frequency B L Phaseshift HSL Color Model F Modify Red Hue Channel f Modify Green Saturation Channel If Modify Blue Luminance Channel r 1 00 C 0 00 ee 100 E G00 re 1 00 Ee 10 00 About a Cancel Pox Two Colors Exchange Overview md E ra i ae GNU Image Manipulation Program Generated by docbook2odf Page 299 of 421 o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o This filter is found in Filters Colors Map Color Exchange This filter replaces a color with another one Options Preview Click Inside to Pick From Color From Color E Red 1 000 Red Threshold 10 000 Green 1 000 Green Threshold 0 000 Blue 1 000 Blue Threshold 0 000 Lock Thresholds To Color ome Red 0 401 Green 0 812 Blue 0 430 A Cancel oP oK GNU Image Manipulation Program Page 300 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o Colormap Rotation Preview Original lt Switch to clockwise Rotated Overview i 10 yj Lo ke e N xX e e 2 o e ke gt 2 3 0 Ww hn o LU GNU Image Manipulation Program Page 301 of 421 Generated by docbook2odf This filter is found in Filters Colors Map Color Map Rotation Colormap Rotation lets you
251. ialogs etc The contents are described systematically in the Toolbox Menu section Tool icons These icons are buttons that activate tools for a wide variety of purposes selecting parts of images painting on them transforming them etc The Toolbox Introduction section gives an overview of how to work with tools and each tool is described systematically in the Tools chapter Foreground Background colors The color areas here show you GIMP s current foreground and background colors which come into play in many operations Clicking on either one of them brings up a color selector dialog that allow you to change to a different color Clicking on the double headed arrow swaps the two colors and clicking on the small symbol in the lower left corner resets them to black and white Brush Pattern Gradient The symbols here show you GIMP s current selections for the Paintbrush used by all tools that allow you to paint on the image painting includes operations like erasing and smudging by the way for the Pattern which is used in filling selected areas of an image and for the Gradient which comes into play whenever an operation requires a smoothly varying range of colors Clicking on any of these symbols brings up a dialog window that allows you to change it Active Image This is a new feature in GIMP 2 2 In GIMP you can work with many images at once but at any given moment one of them is the active image Here you find a Small iconic
252. ic things without using the Layers dialog but even moderately sophisticated GIMP users find it indispensible to have the Layers dialog available at all times Brushs Patterns Gradients The docked dialog below the layer dialog shows the dialogs for managing brushes patterns and gradients This is a minimal setup There are over a dozen other types of dialogs used by GIMP for various purposes but users typically create them when they are needed and close them when they are not Knowledgeable users generally keep the Toolbox with Tool Options and Layers dialog around at all times The Toolbox is essential to many GIMP operations in fact if you close it GIMP will exit You are asked to confirm that you want to do this though The Tool Options are actually a separate dialog shown docked to the Main Toolbox in the screenshot Knowledgeable users almost always have them set up this way it is very difficult to use tools effectively without being able to see how their options are set The Layers dialog comes into play whenever you work with an image that has multiple layers once you advance beyond the very most basic stages of GIMP expertise this means almost always And finally of course the necessity of having images displayed in order to work with them is perhaps obvious If your GIMP layout gets trashed fortunately the arrangement shown in the screenshot is pretty easy to recover In the File menu from the Main Toolbox selecting File Dia
253. icking on the Green Button so the image occupies most of the screen Activating the Command e You can access this command from the image menubar through View Full Screen e or by using the keyboard shortcut F11 Info Window The Info Window command displays general information about the current image as well as information about the pixel which is currently under the mouse pointer Activating the Command e You can access this command from the image menubar through View Info window e or by using the keyboard shortcut Shift Ctrl Description of the Info Window The Info Window displays basic information about the current image including its name and a thumbnail as well as about the pixel which is currently under the mouse pointer GNU Image Manipulation Program Page 239 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Navigation Window The Navigation Window command opens the navigation window This allows you to easily navigate through the image to set zoom levels and to move the visible parts of the image You can find more information about using it in the Navigation dialog chapter Activating the Command e You can access this command from the image menubar through View Navigation Window e or by using the keyboard shortcut Shift Ctri N e You can also access it more rapidly by clicking on the icon in the lower right corner of the image window Di
254. icking on the current gradient in the Brush Pattern Gradient area e From an image menu Dialogs Gradients e From the Tab menu in any dockable dialog Add Tab Gradients e From the image by using the G shortcut Using the Gradients dialog The most basic and most commonly used operation with the dialog is simply to click on one of the gradients in the scrollable list in order to make it GIMP s current gradient which will then be used by any operation that involves a gradient If you double click on a gradient you open the Gradient Editor where you will be able to edit its name Note however that you are only allowed to change the names of gradients that you have created yourself not the ones that come pre installed with GIMP If you try to rename a pre installed gradient you will be able to edit the name but as soon as you hit return or click somewhere else the name will revert to its original value It is a general rule that you cannot alter the resources that GIMP pre installs for you brushes patterns gradients etc only ones that you create yourself The buttons at the bottom of the dialog allow you to operate on gradients in several ways The functions performed by these buttons can also be accessed from the dialog pop up menu activated by right clicking anywhere in the gradient list The menu also gives you one additional function Gradient Editor The Gradient Editor allows you to edit the colors i
255. ies Fortunately paths are represented in SVG files in almost exactly the same way they are represented in GIMP Actually fortune has nothing to do with it GIMP s path handling was rewritten for GIMP 2 0 with SVG paths in mind This compatibility makes it possible to store GIMP paths as SVG files without losing any information You can access this Capability in the Paths dialog It also means that GIMP can create paths from SVG files saved in other programs such as Inkscape or Sodipodi two popular open source vector graphics applications This is nice because those programs have much more powerful path manipulation tools than GIMP does You can import a path from an SVG file using the Paths dialog The SVG format handles many other graphical elements than just paths among other things it handles figures such as squares rectangles circles ellipses regular polygons etc GIMP 2 0 cannot do anything with these entities but GIMP 2 2 can load them as paths Creating paths is not the only thing GIMP can do with SVG files It can also open SVG files as GIMP images in the usual way Brushes GNU Image Manipulation Program Page 33 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o A brush is a pixmap or set of pixmaps used for painting GIMP includes a set of 10 paint tools which not only perform operations that you would think of as painting but also operations suc
256. ift Ctrl eh Navigation Window Shift Ctril N S Display Filters Show Selection Ctr T Show Layer Boundary Show Guides Shit Ctrl T Snap to Guides Show Grid Snap to G rid Padding Color v Show Menubar Show Rulers Shit Ctri R Show Scrollbars Show Statusbar This section describes the View menu which contains commands that affect the visibility or appearance of the image and various elements of the interface Besides the commands described here you may also find other entries in the menu They are not part of GIMP itself but have been added by extensions plug ins You can find information about the functionality of a plug in by referring to its documentation New View The New View command creates a new image window for the current image which you can set up differently from the existing display You can create multiple views of any image which are numbered 1 2 etc but only the zoom factor and other viewing options may be different Any changes other than viewing changes which you make in one window also appear in the other displays which show the same image The new views are not separate image files they are simply different aspects of the same image You might use multiple views for example if you were working on individual pixels at a high zoom factor You could then see the effects your changes would have on the image at a normal size You can delete a view by closing its window If you close th
257. ilar except that instead of completely replacing the existing selection with the selection produced from the alpha channel they either add the two selections subtract the alpha selection from the existing selection or create a selection that is the intersection of the two Activating the Command e You can access this command from the image menubar through Layer Transparency Alpha to Selection e or from the pop up menu which appears when you right click on the active layer in the Layer Dialog Example GNU Image Manipulation Program Page 274 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o New layer Background Add to Selection The Add to Selection command creates a selection in the image from the pixels of the active layer according to their transparency Opaque areas are fully selected transparent areas are unselected and translucent areas are partially selected This selection is added to an existing selection The alpha channel itself is not changed The other commands tn this group of operations are similar except that instead of adding to the existing selection with the selection produced from the active layer they either completely replace the selection with a selection produced from the alpha selection subtract the alpha selection from the existing selection or create a selection that is the intersection of the two Activating the Comman
258. ill be first rendered as a floating selection This method of dithering looks at the current pixel color and retrieving the closest values from the palette These colors are then distributed to the pixel areas below and to the right of the original pixel Trademarked by CompuServe with LZW compression patented by Unisys GIF images are in 8 bit indexed color and support binary transparency but not semi transparency They can also be loaded in interlaced form by some programs The GIF format also supports animations and comments Use GIF for transparent Web graphics and GIF animations For most purposes though PNG can be used in place of GIF and is a better choice GNU s Not Unix is a project of a free Unix like operative system The project was started back in 1983 thanks to the effort of the Free Software Fundation an organization devoted to the creation and support of free software GIMP is an official GNU application You can find a better definition on the wikipedia site To place a guide left click and hold on a ruler and drag the mouse pointer in to the image A guide appears and follows the pointer You can so place two guides a horizontal GNU Image Manipulation Program Page 402 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o hn S o one and a vertical one They appear as blue dashed lines They do not print Guides are a convenient way to position a selection or a la
259. illa database with the entire Gnome project At the time this is being written Gnome Bugzilla contains 148632 bug reports no make that 148633 GNU Image Manipulation Program Page 413 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Making sure it s a Bug The first thing you should do before reporting a bug is to make an effort to verify that what you are seeing really is a bug It is hard to give a method for doing this that applies to all situations but reading the documentation will often be useful and discussing the question on IRC or a mailing list may also be quite helpful If you are seeing a crash as opposed to mere misbehavior the odds that it is a true bug are pretty high well written software programs are not designed to crash under any circumstances In any case if you have made an conscientious effort to decide whether it is really a bug and at the end still aren t sure then please go ahead and report it the worst that can happen is that you will waste a bit of time for the development team Actually there are a few things that are known to cause GIMP to crash but have turned out to be too inconvenient to be worth fixing One of them is asking GIMP to do something that requires vast amounts of memory such as creating an image one million pixels on a Side You should also make sure that you are using an up to date version of GIMP reporting bugs that have
260. ily you don t need to give any arguments when starting GIMP but here Is a list of some that may at one time or anther be useful This is not a complete list on Unix systems you can get a complete list by running man gimp in a terminal window Known platforms The GIMP is the most widely supported image manipulation available today The platforms that The GIMP is known to work on include GNU Linux Apple Mac OS X Darwin Microsoft Windows 95 98 Me XP NT4 and 2000 OpenBSD NetBSD FreeBSD Solaris SunOS AIX HP UX Tru64 Digital UNIX OSF 1 IRIX OS 2 and BeOS The GIMP can easily be ported to other operating systems because of its source code availability Language All being well GIMP detects the system language This may fail on some machines and you may want use another language It is possible to change the language In LINUX in console mode type LANGUAGE en GIMP or LANG en GIMP replacing en by fr de according to the language you want In WINDOWS XP Control Panel System Advanced Environment button In System Variables area Add button Enter LANG for Name and fr or de for Value Watch out You have to click on three successive OK to validate your choice If you often change language you can create a batch file Open NotePad Type the following commands for french for instance set lang fr cd c Program Files GIMP 2 0 bin GIMP 2 2 exe Save this file as GIMP FR BAT or another name but always with a
261. in Filters Distorts Curve Bend This filter allows you to create a curve that will be used to distort the active layer or selection The distortion is applied gradually from an image or selection border to the other Options Example t 3 o N x o e 2 8 o 3 gt 2 a o Ww hn o c o GNU Image Manipulation Program Page 348 of 421 Generated by docbook2odf GIMP GIMP Emboss Function C Bumpmap Emboss F Do Preview Parameter Settings Azimuth J o 0 00 E Elevation _ J ps 29 Depth P J 17 a Cancel Overview This filter is found in Image gt Filters Distorts Emboss You can use it only with RGB images If your image is grayscale it will be grayed out in the menu It stamps and carves the active layer or selection giving it relief with bumps and hollows Bright areas are raised and dark ones are carved You can vary the lighting Options IWar arp 7 Tv e N x e e 2 o e 3 gt 2 ke d hn lt o GNU Image Manipulation Program Page 349 of 421 Generated by docbook2odf Deform Radius f 20 l Deform Amount 6h Ul 0 30 Remove C Shrink Bilinear Adaptive Supersample Max Depth a 2 Threshold 2 00 FF sJ Reset Cancel Pox Overview This filter is found in Image gt Filters Distorts IWarp This filter allows you to deform interactively some parts of the image and
262. in the Brush Pattern Gradient area of the Toolbox Clicking on the gradient symbol in the Toolbox is an alternative way of bringing up the Gradients dialog A few useful things to know about GIMP s gradients e The first four gradients in the list are special they use the Foreground and Background colors from the Toolbox Color Area instead of being fixed FG to BG RGB is the RGB representation of the gradient from the Foreground color to the Background color in Toolbox FG to BG HSV counter clockwise represents the hue succession in Color Circle from the selected hue to 360 FG to BG HSV clockwise represents the hue succession in Color Circle from the selected hue to 0 With FG to transparent the selected hue becomes more and more transparent You can modify these colors by using the Color Selector Thus by altering the foreground and background colors you can make these gradients transition smoothly between any two colors you want e Gradients can involve not just color changes but also changes in opacity Some of the gradients are completely opaque others include transparent or translucent parts When you fill or paint with a non opaque gradient the existing contents of the layer will show through behind it e You can create new custom gradients using the Gradient Editor You cannot modify the gradients that are supplied with GIMP but you can duplicate them or create new ones and then edit those The gradients that are
263. in the Document create one stating the title year authors and publisher of the Document as given on its Title Page then add an item describing the Modified Version as stated in the previous sentence J Preserve the network location if any given in the Document for public access to a Transparent copy of the Document and likewise the network locations given in the Document for previous versions it was based on These may be placed in the History section You may omit a network location for a work that was published at least four years before the Document itself or if the original publisher of the version it refers to GNU Image Manipulation Program Page 418 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o gives permission K For any section Entitled Acknowledgements or Dedications Preserve the Title of the section and preserve in the section all the substance and tone of each of the contributor acknowledgements and or dedications given therein L Preserve all the Invariant Sections of the Document unaltered in their text and in their titles Section numbers or the equivalent are not considered part of the section titles M Delete any section Entitled Endorsements Such a section may not be included in the Modified Version N Do not retitle any existing section to be Entitled Endorsements or to conflict in title with any Invariant Section O Preser
264. inal Merged Layer should be Expanded as necessary Clipped to image Clipped to bottom layer a Cancel Flatten Image Image Oh Duplicate Ctrl D Mode Transform i m At Canvas to Layers Print Size 2 Crop Image Autocrop Image Zealous Crop Merge Visible Layers Ctrl M Flatten Image Guides HH Configure Grid Separate The Flatten Image command merges all of the layers of the image into a single layer with no alpha channel After the image is flattened it has the same appearance it had before The difference is that all of the image contents are in a single layer without transparency If there are any areas which are transparent through all of the layers of the original image the background color is visible This operation makes significant changes to the structure of the image It is normally only necessary when you would like to save an image in a format which does not support levels or transparency an alpha channel Activating the Command e You can access this command from the image menubar through Image Flatten Image Guides New Guide New Guide by Percent New Guides from Selection Remove all Guides The Guides submenu contains various commands for the creation and removal of guides xe e N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 255 of 421 Generated by docbook2odf Activating the Submenu
265. increase the selection with black you reduce the selection This procedure lets you create a selection very precisely Moreover Channel Masks let you save your selections you can retrieve them later by using the Channel to selection command from the Channel menu Channel masks are so important in Gimp that a special type has been implemented the Quick mask See Selection mask for more details Markeringsmaske av og til ogsa kalla Kanalmaske Denne maska representerer alfakanalen til biletet Ved a mala med kvitt fjernar du maska og aukar markeringa Maler du med svart blir markeringa redusert Pa denne maten kan du avgrensa markeringa heilt nayaktig Ved hjelp av kanalmaskene kan du ogsa lagra markeringane og henta dei tilbake etter nskje med kommandoen Kanal til maske i kanalmenyen Kanalmaskene er mykje brukte i GIMP Difor finn du ogsa ei spesialmaske som bli kalla Snarmaske Sja meir om dette i Markeringsmasker A path is a one dimensional tracing either polygonal or curved or a mixture of segments of both types In GIMP the main uses of paths are either to form the boundaries of selections or to be stroked to create visible curves on an image See the Paths section for basic information on paths and the Path Tool section for information on how paths can be created and edited In the Procedure Database PDB all of the functions which GIMP and its extensions make available are registered Developers can look up useful informati
266. indow where they will be opened in the existing Image as new layers Shortcut editor You can now edit your shortcuts in a dedicated dialog as well as continue to use the little Known dynamic shortcuts feature which has been there since 1 2 Plug in previews We have provided a standard preview widget for plug in authors which greatly reduces the amount of code required to support previews David Odin has integrated this widget into all the current filters so that now many more filters in the GIMP include a preview which updates in real time and the various previews behave much more consistently Real time previews of transform operations The transform tools shear scale perspective and rotate can now show a real time preview of the result of the operation when the tool is in Traditional mode Previously only a transforming grid was shown GNOME Human Interface Guide conformance A lot of work has been done on making the GIMP s interface simpler and more usable for newcomers Most dialogs now follows the GNOME HIG to the best of our knowledge In addition dialogs have separated out or removed many Advanced options and replaced them with sane defaults or hidden them in an expander GNU Image Manipulation Program Page 6 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o GTK 2 4 migration e Menus use the GtkUIManager to generate menu structure dynamically from
267. ion Program Page 78 of 421 Generated by docbook2odf Text Embellishing Text Fear the Cow There are many things you can do to vary the appearance of text beyond just rendering it with different fonts or different colors By converting a text item to a selection or a path you can fill it stroke the outlines transform it or generallly apply the whole panoply of GIMP tools to get interesting effects As a demonstration of some of the possibilities try out the logo scripts in the Toolbox menu at Xtns Script Fu Logos Each of these scripts allows you to enter some text and then creates a new image showing a logo constructed out of that text If you would like to modify one of these scripts or construct a logo script of your own the Using Script Fu and Script Fu Tutorial sections should help you get started Of course you don t need Script Fu to create these sorts of effects only to automate them Adding Fonts For the most authoritative and up to date information on fonts in GIMP consult the Fonts in GIMP 2 0 page at the GIMP web site This section attempts to give you a helpful overview GIMP uses the FreeType 2 font engine to render fonts and a system called Fontconfig to manage them GIMP will let you use any font in Fontconfig s font path it will also let you use any font it finds in GIMP s font search path which is set on the Font Folders page of the Preferences dialog By default the font search path includes a system
268. ion to be able to use them Script Fu a dialect of Scheme isn t the only scripting language available for Gimp But Script Fu is the only scripting language that is installed by default Other available scripting extensions are Perl and Tcl You can download and install both extensions at the Gimp Plugin Registry One of the great things about Script Fu is that you can share your script with all your Gimp friends There are many scripts that come with Gimp by default but there are also vast quantities of scripts that are available for download all around the Internet If you have downloaded a script copy or move it to your scripts directory It can be found in the Preferences Folders Scripts Do a refresh by using Exts Script Fu Refresh Scripts from the toolbox The script will now appear in one of your menus If you don t find it look for it under the root file menu filters If it doesn t appear at all something was wrong with the script e g it contains syntax errors A common error when you are dealing with Script Fus is that you simply bring them up and press the OK button When nothing happens you probably think that the script is broken or buggy but there is most likely nothing wrong with it Think again Did you really read the information in the dialog or did you just press the button If you forgot an input the script needs or if you gave it the wrong input the script will fail One of the most common errors is that the f
269. is a contour line dividing areas that are more than half selected from areas that are less than half selected You should always bear in mind when looking at the dashed line that represents the selection that it only tells you part of the story If you want to see the selection in complete detail the easiest way is to click the QuickMask button in the lower left corner of the image window This causes the selection to be shown as a translucent overlay atop the image Selected areas are unaffected unselected areas are reddened The more completely selected an area is the less red it appears QuickMask mode and its uses are described in detail below Meanwhile if you are following this discussion by trying things out in GIMP you should know that many operations work differently in QuickMask mode so go ahead and toggle it off again for now by clicking the QuickMask button once more Feathering With the default settings the basic selection tools such as the Rectangle Select tool create sharp selections Pixels inside the dashed line are fully selected and pixels outside completely unselected You can verify this by toggling QuickMask you see a clear rectangle with sharp edges surrounded by uniform red In the Tool Options however is a checkbox called Feather edges If you enable this the tool will instead create graduated GNU Image Manipulation Program Page 26 of 421 Generated by docbook2odf xe e N E O O
270. is flipped a new layer with a Floating Selection is created You can use this tool to create reflexions Activate Tool e The Flip Tool can be called in the following order from the image menu Tools Transform Tools Flip e The Tool can also be called by clicking the tool icon pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 137 of 421 Generated by docbook2odf Key modifiers Defaults Options Horizontal C Vertical pe O N E O O 2 S O xe a 2 xe o 4 G d 0 S o GNU Image Manipulation Program Page 138 of 421 Generated by docbook2odf Color Tools Color Balance Tool The color balance tool modifies the color balance of the active selection or layer Activate Tool The Color Balance Tool can be called in the following order from the image menu Tools Color Tools Color Balance Options Adjust Color Balance Background Untitled Select Range to Modify Shadows tf Midtones Highlights Modify Selected Range s Color Levels Cyan P e J Red o l Magenta Green o Yellow tJ Blue Jo Reset Range JY Preserve Luminosity Z Preview FJ Reset M Cancel Pox Hue Saturation Tool The Hue Saturation tool is used to adjust hue saturation and lightness levels on a range of color weights for the selected area or active layer Activate Tool You can call the Hue Saturation T
271. istinct from that of the Document and from those of previous versions which should if there were any be listed in the History section of the Document You may use the same title as a previous version if the original publisher of that version gives permission B List on the Title Page as authors one or more persons or entities responsible for authorship of the modifications in the Modified Version together with at least five of the principal authors of the Document all of its principal authors if it has fewer than five unless they release you from this requirement C State on the Title page the name of the publisher of the Modified Version as the publisher D Preserve all the copyright notices of the Document E Add an appropriate copyright notice for your modifications adjacent to the other copyright notices F Include immediately after the copyright notices a license notice giving the public permission to use the Modified Version under the terms of this License in the form shown in the Addendum below G Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document s license notice H Include an unaltered copy of this License I Preserve the section Entitled History Preserve its Title and add to it an item Stating at least the title year new authors and publisher of the Modified Version as given on the Title Page If there is no section Entitled History
272. it modify and manage your layers You can think of layers as a stack of slides or clothes on your body Using layers you can construct an image of several conceptual parts each of which can be manipulated without affecting any other part of the image Layers are stacked on top of each other The bottom layer is the background of the image and the components in the foreground of the image come above it b fel a UGC AANUAL Activate Dialog The Layer dialog can be called in many ways e from the toolbox menu File Dialog Layers e from the image menu Dialog Layers e from an other dialog menu Add Tab Layers e from the default shortcut CtriL Using the Layerdialog pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 155 of 421 Generated by docbook2odf Layer masks i Add a Mask to the Layer Background 2 Untitled Initialize Layer Mask to fe White Full Opacity Black Full Transparency O Layer s Alpha Channel Transfer Layer s Alpha Channel Selection Grayscale Copy of Layer Invert Mask Channels dialog Channels The Channels dialog is the main interface to edit modify and manage your channels Channels have a double usage This is why the dialog is divided into two parts the first part for color channe
273. ive layer or selection so that it looks like a black and white photocopy as if toner transfered was based on the relative darkness of a particular region This is achieved by darkening areas of the image which are measured to be darker than a neighborhood average and setting other pixels to white Starting filter You can find this filter from the image menu through Filters Artistic Photocopy Options X Preview Mask radius 30 96 5 Sharpness p aa aja 0 800 B Percent black m 0 200 B Percent white m 0 200 5 Soft Glow Mode of action pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 368 of 421 Generated by docbook2odf This filter lights the image with a soft glow Soft Glow produces this effect by making brigth areas of the image brighter Starting filter You can find this filer in the Image menu Filters Atistic Soft Glow Options xX Preview Glow radius OE 10 00 5 Brightness R 0 75 B Sharpness y 0 85 B GNU Image Manipulation Program Generated by docbook2odf Page 369 of 421 pe O N E O O 2 S O xe a 2 xe o G d 3 S o Map filters Map filters introduction Map filters use an object named map to modify an image you map the image to the object So you can create 3D effects by mapping your image to another previously embossed image Bumpmap Filter or to a sphere Map
274. izontally 5 O Blur Type IIR gt O O wyReset 2 Cancel O pe a 2 1 G 3 S o t GNU Image Manipulation Program e Page2960f 421 Generated by docbook2odf Color filters Introduction to Color Filters The Color filters group contains several filters to modify colors in an image a layer ora selection You can find filters to compose decompose uncolor colors and many other effects Adjust FG BG Overview This filter is found in Filters Colors Map Adjust FG BG Adjust FG BG belongs to color map filters which make connection between a color source and an image Here image pixels having ForeGround color will turn to black while pixels having BackGround color will turn to white Other colors will turn to their complementary color There will be no change if FG is black and BG Is white pe O N 4 O O 2 S O xe a 2 xe o G 3 S o GNU Image Manipulation Program Page 297 of 421 Generated by docbook2odf Options This filter has no option Alien Map 2 Overview a ee eres yr re LUST Te This filter is found in Filters Colors Map Alien map 2 This filter renders very modified colors by applying trigonometric functions Alien Map 2 can work on RGB and HSV Options o l 3 o N x e o 2 8 o v gt 2 v o Ww hn o c o GNU Image Manipulation Program Page 298 of 421 Generated by docbook2odf R H Erequency R H Phases
275. ked For the most part setting up GIMP Is very easy and you can just accept the defaults at each step and possibly adjust things later using the Preferences dialog The main thing you might want to give a little thought to at the start is the amount of memory to allocate for GIMP s tile cache Here is a walk through of the setup process 1 Since this window mentions the GNU General Public License you know it is truly a Welcome dialog you are entering into Also note the Continue button The GIMP does not even ask that you agree to it merely whether you want to continue Feel free to press the continue button The GIMP GNU Image Manipulation Program Copyright C 1995 2004 Spencer Kimball Peter Mattis and the GIMP Development Team This program is free software you can redistribute it and or modify it under the terms of the GNU General Public License as published by the Free Software Foundation either version 2 of the License or at your option any later version This program is distributed in the hope that it will be useful but WITHOUT ANY WARRANTY without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE See the GNU General Public License for more details You should have received a copy of the GNU General Public License along with this program if not write to the Free Software Foundation Inc 59 Temple Place Suite 330 Boston MA 02111 1307 USA Continue 2 The purpose of thi
276. l filesystem with enough free space several hundred MB On a UNIX system you may want to use the system wide temp dir tmp or var tmp Swap folder home marco gimp 2 2 a o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 12 of 421 Generated by docbook2odf Chapter GIMP Concepts pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 13 of 421 Generated by docbook2odf Main Windows in GIMP The screenshot above shows the most basic arrangement of GIMP windows that can be used effectively Three windows are shown The Main Toolbox This is the heart of the GIMP It contains the highest level menu plus a set of icon buttons that can be used to select tools and more Tool options Docked below the main Toolbox is a Tool Options dialog showing options for the currently selected tool in this case the Rectangle Select tool An image window Each image open in GIMP is displayed in a separate window Many images can be open at the same time the limit is set only by the amount of system resources It is possible to run GIMP without having any images open but there are not very many useful things to do then Layers Dialog This dialog window shows the layer structure of the currently active image and allows it to be manipulated in a variety of ways It is possible to do a few very bas
277. lared variables use the list function BRRRRBEE Li sStmS48Staliblic BREE This will compose and return a list containing the values held by the variables a b and c For example BERRRREE 1 cU an Se ae Ue be Se ce TTT BERR RR RRR RRR li SCS 4ESHalblc BRRREEEE BREE GNU Image Manipulation Program Page 88 of 421 Generated by docbook2odf xe O N E O O 2 S O xe a 2 xe o hn S o This code creates the list 5 431 2 3 Accessing Values In A List To access the values in a list use the functions car and cdr which return the first element of the list and the rest of the list respectively These functions break the list down into the head tail construct mentioned earlier The car Function car returns the first element of the list the head of the list The list needs to be non null Thus the following returns the first element of the list BERRREEE carl first 820 third BERERE which is EREEREER first BREE The cdr function cdr returns the rest of the list after the first element the tail of the list If there is only one element in the list it returns an empty list BORRRBER car first 82E third BEREEE returns BRR RRRER 2 Chird BREE whereas the following BRRRREEE cdr oneHandflonly LT TTT returns BERR RREE BREE Accessing Other Elements In A List OK great we can get the first element in a lis
278. lares two local variables a and b initializes them then prints the sum of the two variables What Is A Local Variable You ll notice that we wrote the summation a b within the parens of the let expression not after it This is because the let statement defines an area in your script in which the declared variables are usable if you type the a b statement after the let statement you ll get an error because the declared variables are only valid within the context of the let statement they are what programmers Call local variables The General Syntax Of let The general form of a let statement is BERRRRRR leti Bvariablesll fexpressionsl l LT TTT where variables are declared within parens e g a 2 and expressions are any valid Scheme expressions Remember that the variables declared here are only valid within the let statement they re local variables White Space Previously we mentioned the fact that you ll probably want to use indentation to help clarify and organize your scripts This is a good policy to adopt and is not a problem in GNU Image Manipulation Program Page 85 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o Scheme white space Is ignored by the Scheme interpreter and can thus be liberally applied to help clarify and organize the code within a script However if you re working in Script Fu s Console window
279. lash png 63 8KB a mousebutton pn 06 2 6 2004 png ai 400 x 300 pixels next png 03 06 2004 Indexed 1 Layer note png 04 13 2004 Remove All Files t Select File Type Automatically Detected GIMP 2 2 introduced a new File Chooser that provides several features to help you navigate quickly to the file you are looking for Perhaps the most important is the ability to create bookmarks for folders that you use often Your list of bookmarks GNU Image Manipulation Program Page 51 of 421 Generated by docbook2odf pe O N E O O 2 S O S a 2 xo o G d 3 S o appears on the left side of the dialog The ones at the top Home Desktop etc come automatically the others you create using the Ada button at the bottom of the list Double clicking on a bookmark takes you straight to that directory At the center of the dialog appears a listing of the contents of the selected directory Subdirectories are shown at the top of the list files below them By default all files in the directory are listed but you can restrict the listing to image files of a specific type using the File Type selection menu that appears beneath the directory listing When you click on a file entry in the listing if it is an image file a preview will appear on the right side of the dialog along with some basic information about the properties of the image Note that previews are cached when they are generated and there are
280. layer with the Anchor layer command If the image does not contain a floating selection this menu entry is insensitive and grayed out If there is an active selection tool the mouse pointer is displayed with an anchor icon when it is outside of the selection A left click then anchors the floating selection You may also click on the New layer command on the Layers dialog which anchors the floating selection to a new layer See Activating the Command e You can access this command from the tmage menubar through Layer Anchor layer e or by using the keyboard shortcut Ctrl H Merge Down The Merge Down command merges the active layer with the layer just below it in the Stack taking into account the various properties of the active layer such as its opacity and combination mode GNU Image Manipulation Program Page 260 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Activating the Command e You can access this command from the image menubar through Layer Merge Down Delete Layer The Delete Layer command deletes the active layer from the image Activating the Command e You can access this command from the tmage menu bar through Layer Delete Layer The Stack Submenu Select Previous Layer Page Up Select Next Layer Page Down Select Top Layer Home Select Bottom Layer End i Raise Layer it Lower Layer i Layer to Top ls Layer to Bottom The layer sta
281. layers You can also create a new layer and fill it with the background you want By doing this you create a digital passe partout a kind of glass mount with a removable back for slipping in a photograph Print Size You can use the Print Size dialog to change the dimensions of a printed image and its resolution This command does not change the number of pixels in the image and it does not resample the image If you want to change the size of an image by resampling it use the Scale Image command Options in the Print Size Dialog GNU Image Manipulation Program Page 251 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Print Size Width Height 1 100 inches resolution 120 035 Y resolution 120 035 gt pixels in The output resolution determines the number of pixels used per unit length for the printed image Do not confuse the output resolution with the printer resolution which is expressed in dpi dots per inch several dots are used to print a pixel When the dialog is displayed the resolution shown in the boxes is the resolution of the original image If you increase the output resolution the printed page will be smaller since more pixels are used per unit of length Conversely and for the same reason resizing the image modifies the resolution Increasing the resolution results in increasing the sharpness of the printed page This is quite
282. le aggregate Translation is considered a kind of modification so you may distribute translations of the Document under the terms of section 4 Replacing Invariant Sections with translations requires special permission from their copyright holders but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections You may include a translation of this License and all the license notices in the Document and any Warranty Disclaimers provided that you also include the original English version of this License and the original versions of those notices and disclaimers In case of a disagreement between the translation and the original version of this License or a notice or disclaimer the original version will prevail If a section in the Document is Entitled Acknowledgements Dedications or History the requirement section 4 to Preserve its Title Section 1 will typically require changing the actual title You may not copy modify sublicense or distribute the Document except as expressly provided for under this License Any other attempt to copy modify sublicense or distribute the Document is void and will automatically terminate your rights under this License However parties who have received copies or rights from you under this License will not have their licenses terminated so long as such parties remain in full compliance The Free Software Foundation may publis
283. liasing information by using a partially intelligent routine that replaces weak color information with weak alpha information In this way areas that contain an element of the selected color will maintain a blended appearance with their surrounding pixels Options Compose Overview GNU Image Manipulation Program Page 311 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o This filter is found in Filters Colors Compose This filter is active in Filters Colors after using Decompose This filter reconstructs an image from its RGB HSV components Options Compose Channels Channel Representations RGB Pena la Red FF 2zinnias RGB png 4 red 8 O HSV elise lh Green Q 2zinnias RGB png 4 green 9 O CMYK B 2zinnias RGB png 4 blue 10 DO CbCr_ITU_R470 lab Blue D YCbCr ITU R709 YCbCr ITU R470_256 YCbCr ITU_R709_ 256 Decompose Overview GNU Image Manipulation Program Page 312 of 421 Generated by docbook2odf t 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o This filter is found in Filters Colors Decompose This filter separates an image into its different components RGB HSV Options Extract Channels RGB RGBA 0 HSV CMY D CMYK Alpha _ LAB YCbCr ITU R470 YCbCr ITU R709 YCbCr ITU R470 256 YCbCr ITU R709 256 x Decompose to layers Filter Pack Ov
284. ll now appear on the currently active layer completely replacing its previous contents pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 393 of 421 Generated by docbook2odf Options Checkerboard Overview Lo ke e N xX e e 2 o e ke gt 2 3 0 Ww hn o LU GNU Image Manipulation Program Page 394 of 421 Generated by docbook2odf Lea W E ae ie De ne ee This filter creates a checkerboard pattern replacing the current layer content Colors used for pattern are current Fore and Back ground colors of toolbox rt O Starting filter You can find this filter in image menu following Filters Render Pattern Checkerboard Options Psychobilly Size 10 Sinus Settings Colors Blend Drawing Settings x Scale 7 Dy 111 3208 l Y Scale E Dy 126 4152 BE Complexity J 12 45 g Calculation Settings Random Seed 1951464883 g New Seed Randomize Do Preview Force Tiling C Ideal Distorted Cancel pe O N E O O 2 S O xe a 2 xe o hn S o GNU Image Manipulation Program Page 395 of 421 Generated by docbook2odf Overview You can find this filter from the image menu through Filters Render Pattern Sinus The Sinus filter lets you make sinusoidally based textures which look rather like watered silk or maybe plywood This plug in
285. ll of the data that goes to make up a GIMP image Because of this XCF files may be quite complicated and there are few programs other than GIMP that can read them When an image Is stored as an XCF file the file encodes nearly everything there Is to know about the image the pixel data for each of the layers the current selection additional channels if there are any paths if there are any and guides The most important thing that is not saved in an XCF file is the undo history The pixel data in an XCF file is represented in a raw uncompressed form each byte of image data equals one byte in the XCF file Thus XCF files for even modestly sized images can be quite large for example a 1000x1000 RGB image with 3 layers will produce an XCF file of over 10 megabytes It is not at all difficult to get XCF files of over 100 megabytes Fortunately although XCF files do not intrinsically compress their data GIMP allows you to compress the files themselves using either the gzip or bzip2 compression methods both of which are fast efficient and freely available Compressing an XCF file will often shrink it by a factor of 10 or more The pixel data in an XCF file is represented in a lossless compressed form the image byte blocks are compressed using the lossless RLE algorithm This means that no matter how many times you load and save an image using this format not a single pixel or other image data will be lost or modified because of this format
286. logs Create New Dock Layers Channels and Paths will give you a Layers dialog just like the one shown In the same menu selecting File Dialogs Tool Options gives you a new Tool Options dialog which you can then dock below the Main Toolbox The section on Dialogs and Docking explains how to dock dialogs There is no need to be able to create a new Main Toolbox because you cannot get rid of the one you have without causing GIMP to exit Unlike some other programs GIMP does not give you the option of putting everything controls and image displays all into a single comprehensive window The GIMP developers have always felt that this is a poor way of working because it forces the program to perform a wide range of functions that are much better done by a dedicated window manager Not only would this waste a lot of programmer time it is almost impossible to do in a way that works correctly across all of the operating systems GIMP is intended to run on Earlier versions of the GIMP up to GIMP 1 2 5 were very profligate with dialogs advanced users often had half a dozen or more dialogs open at once scattered all over the screen and very difficult to keep track of GIMP 2 0 is much better in this respect because it allows dialogs to be docked together in a flexible way The Layers dialog in the screenshot actually contains four dialogs represented by tabs Layers Channels Paths and Undo The system takes a little while to learn but once
287. lor Numbering Start Index l l Font Courier M At Top F At Bottom qP Add Remove Overview Film filter allows the user to merge several pictures into a photographic film drawing This filter does not invert colors so it does not imitate negative film of the sort used to produce prints Instead you should think of the result as an imitation of slide film or cinema film Accessing this Filter This filter is in Image Filters Combine Film Options Double click on the tool buttons opens the Tool Options dialog GNU Image Manipulation Program Page 400 of 421 Generated by docbook2odf pe O N E O O 2 0 O S a 2 xe o 4 d 0 S o Click on the colors to change the colors These open a new dialog window if it wasn t open yet otherwise the corresponding dialog gets focus This accepts the new value you typed in a text field and returns focus to canvas Menus can also be activated by Alt with the letter underscored in the menu name This fits the windows to the image size Scrolling by keys is accelerated i e it speeds up when you press Shift arrows or jumps to the borders with Ctrl arrows Drag off the horizontal or vertical ruler to create a new guideline Drag a guideline onto the ruler to delete it This places a copy of the selection to the GIMP clipboard Refers to transparency An Alpha Channel allows transparency control Certain image formats may only contain a single Alpha Channel
288. ls and the second part for selection masks Color channels Color channels apply to the image and not to a specific layer Basically three primary colors are necessary to render all the wide range of natural colors As other digital software the Gimp uses Red Green and Blue as primary colors The first and primary channels display the Red Green and Blue values of each pixel in your image In front of each channel is a thumbnail displaying a grayscale representation of each channel where white is 100 and black is 0 of the primary color Alternatively tf your image Is not a colored but a Grayscale image there is only one primary channel called Gray For an Indexed image with a fixed number of known colors there is also only one primary channel called Indexed Then there is a optional channel called Alpha This channel displays transparency values of each pixel in your image In front of this channel is a thumbnail displaying a grayscale representation of the transparency where white Is opaque and visible and black is transparent and invisible If you create your image without transparency then the Alpha channel is not present but you can add it from the Layers dialog menu Also if you have more than one layer in your image Gimp automatically creates an Alpha channel GNU Image Manipulation Program Page 156 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 G d 0 S o Gimp doesn t suppor
289. lso create new ones Some of the predefined palettes are commonly useful Such as the Web palette which contains the set of colors considered web safe many of the palettes seem to have been chosen more or less whimsically You can access all of the available palettes using the Palettes dialog This is also the starting point if you want to create a new palette Palette Editor x Plasma copy Untitled Columns 16 Double clicking on a palette in the Palettes dialog brings up the Palette Editor showing the colors from the palette you clicked on You can use this to paint with the palette clicking on a color sets GIMP s foreground to that color as shown in the Color Area of the Toolbox Holding down the Ctrl key while clicking on the other hand sets GIMP s background color to the color you click on You can also as the name implies use the Palette Editor to change the colors in a palette so long as it is a palette that you have created yourself You cannot edit the palettes that are supplied with GIMP however you can duplicate them and then edit the copies When you create palettes using the Palette Editor they are automatically saved as soon as you exit GIMP in the palettes folder of your personal GIMP directory Any palette files in this directory or in the system palettes directory created when GIMP is installed are automatically loaded and shown in the Palettes dialog the next time you start GIMP You can also
290. lters Map Make Seamless to adjust the Image so it will tile seamlessly in your background GIMPressionist Overview o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 363 of 421 Generated by docbook2odf You can find this filter via the image menu under Filters Artistic GIMPressionist It s the king of Artistic filters It can do what Cubism and Apply Canvas do and much more It gives your image the look of a painting All is going as if your image was painted again on a paper and with a brush you d have choosen It works on the active layer or selection Parameter Settings GIMPressionist Orientation Map Editor Overview The Orientation map editor is an annexe of the GlMPressionist filter You can get to it by clicking on the Edit button in the Orientation tab With this editor you can set the direction that brush strokes given by filter will have Parameter Settings GNU Image Manipulation Program Page 364 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o Vectors Type Normal Vortex Vortex2 VMortex3 Voronol Preview Add Angle Angle offset Strength Strength exp You can place one or several vectors You can set their direction and their strength They will act ont the corresponding GIMPressionist S Overview area of the image ize Map Editor
291. lug ins to their defaults Because it is a dramatic step it asks you to confirm that you really want to do it Be careful you cannot undo this command Activating the Command e You can access this command from the image menubar through Filters Reset all Filters GNU Image Manipulation Program Page 285 of 421 Generated by docbook2odf y xe O N E O O 2 S O xe a 2 xe o d 3 S o Chapter Filters pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 286 of 421 Generated by docbook2odf Filter introduction A filter is a special kind of tool designed to take an input layer or image apply a mathematical algorithm to it and return the input layer or image in a modified format The GIMP uses filters to achieve a variety of effects and those effects are discussed here e Blur e Colors e Noise e Edge Detect e Enhance e Generic e Glass Effects e Light Effects e Distorts e Artistic e Map e Render e Web e Animation e Combine o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o GNU Image Manipulation Program Page 287 of 421 Generated by docbook2odf Blur filters Blur filters introduction This is a set of filters that blur images or parts of them in various ways If there is a selection only the selected parts of an Image will be blurred There may however be some leakage of col
292. m 1 Before invoking the filter Select File New Image Add a transparent layer with Layers Layers and Channels New Layer Set the foreground color in the toolbox to black and set the background to white 2 Open IFS Compose Start by rotating the right and bottom triangles so that they point upward You ll now be able to see the outline of what s going to be the tip and sides of the leaf If you have problems it may help to know that the three vertices of a triangle are not equivalent 3 To make the leaf symmetrical adjust the bottom triangle to point slightly to the left and the right triangle to point slightly to the right 4 Press New to add a component to the composition This is going to be the stem of the leaf so we need to make it long and thin Press Stretch and drag to stretch the new triangle Don t be alarmed if this messes up the image just use Scale to adjust the size of the overlong triangle You ll probably also have to move and rotate the new fractal to make it look convincing 5 You still have to make it look more leaf like Increase the size of the top triangle y pe O N E O e 2 S O xe a 2 xe o 4 hn S o GNU Image Manipulation Program Page 387 of 421 Generated by docbook2odf until you think it s thick and leafy enough Adjust all fractals until you re happy with the Shape Right click to get the popup menu and choose Select all Now all components are selected
293. m Page 353 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Options Newsprint Resolution Input SPI j Output LPI Cell Size Screen Separate to RGB Black Pullout 5 Red Green Blue Angle 115 0 B Spot Function Round OG 0 22 50 90 Lock Channels Factory Defaults Antialiasing Oversample 1 B Overview This filter is found in Image gt Filters Distorts Newsprint This filter halftones the image using a clustered dot dither Halftoning is the process of rendering an image with multiple levels of grey or colour i e a continuous tone image on a device with fewer tones often a bi level device such as a printer or typesetter The basic premise is to trade off resolution for greater apparent tone depth this is known as Spatial dithering There are many approaches to this the simplest of which is to throw away the low order bits of tone information this is what the posterize filter does Unfortunately the results don t look too good However no spatial resolution is lost This filter uses a clustered dot ordered dither which reduces the resolution of the image by converting cells into spots which grow or shrink according to the intensity that cell needs to represent Imagine a grid Super imposed on the original image The image is divided into cells by the grid each cell will ultimately hold a single spot made up of multi
294. mage Manipulation Program Generated by docbook2odf Hinting Force auto hinter x Antialiasing Justify Indent 0 0 a Line l oo O B spacing pseirs eer fran cs a Open Clear Page 151 of 421 pe O N E O O 2 S O xe a 2 xe o G d 3 S o Color and Indicator Area Color Area Indicator Area This part of the Toolbox shows the currently selected brush pattern and gradient Clicking on any of them brings up a dialog that allows you to change it Active image area A thumbnail of the active image can be displayed in this area if the Display Active Image option is checked in Preferences Toolbox pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 152 of 421 Generated by docbook2odf Chapter Dialogs pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 153 of 421 Generated by docbook2odf Dialog introduction Dialogs are the most common means of setting options and controls in the GIMP The most important dialogs are explained in this section o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 154 of 421 Generated by docbook2odf Image structure related dialogs Layers dialog lt gt Bnew Layer T Backgrouna The Layers dialog is the main interface to ed
295. mage Manipulation Program Page 167 of 421 Generated by docbook2odf Brushes Circle Fuzzy 17 17x17 H The Brushes dialog is used to select a brush for use with painting tools see the Brushes section for basic information on brushes and how they are used in GIMP The dialog also gives you access to several functions for manipulating brushes You can select a brush by clicking on it in the list it will then be shown in the Brush Pattern Gradient area of the Toolbox A few dozen basic brushes come pre installed with GIMP along with a few assorted bizarre ones that mainly serve to show you the range of possibilities You can also create custom brushes using the Brush Editor or by saving images in a special brush file format Activate Dialog The Brushes dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in several ways e From the Toolbox menu File Dialogs Brushes e From the Toolbox menu File Dialogs Create New Dock Brushes Patterns and Gradients This gives you a dock containing three dialogs with the Brushes dialog one of them e From the Toolbox by clicking on the brush symbol in the Brush Pattern Gradient area e From an image menu Dialogs Brushes e From the Tab menu in any dockable dialog Add Tab Brushes e From the Tool Options dialog for any of the paint tools by clicking on the Brush icon button you get a popup with similar functi
296. mage can be decomposed into one or more color channels for an RGB image into R G and B channels for a grayscale image into a single Value channel Layers that support transparency have an additional channel the alpha channel Each channel supports a range of intensity levels from 0 to 255 integer valued Thus a black pixel is encoded by 0 on all color channels a white pixel by 255 on all color channels A transparent pixel is encoded by 0 on the alpha channel an opaque pixel by 255 For RGB images It is convenient to define a Value pseudochannel This is not a real color channel it does not reflect any information stored directly in the image Instead the Value at a pixel is given by the equation V max R G B Essentially the Value is what you would get at that pixel if you converted the image to Grayscale mode For more information on channels please consult the Working with Images section Using the Histogram dialog Navigation Dialog Navigation PE Display Navigation The Navigation dialog is designed to offer easy movement around the active image if the zoom is set higher than what the image window can display If this is the case there is an GNU Image Manipulation Program Page 164 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o inversely colored rectangle that shows the location of the current view area in respect to the image This rectangular
297. mage entirely it doesn t make sense to use these functions because you re not changing an existing image However when you are changing an existing image you most surely want to use these functions Undoing a script works nearly flawlessly when using these functions Extending The Script A Little More Now that we have a very handy dandy script to create text boxes let s add two features to it e Currently the image is resized to fit exactly around the text there s no room for anything like drop shadows or special effects even though many scripts will automatically resize the image as necessary Let s add a buffer around the text and even let the user specify how much buffer to add as a percentage of the size of the resultant text e This script could easily be used in other scripts that work with text Let s extend it so that it returns the image and the layers so other scripts can call this script and use the image and layers we create Modifying The Parameters And The Registration Function To let the user specify the amount of buffer we ll add a parameter to our function and the registration function BERRRREE define script fu text boxfinTest inFont amp inFontSizeflinTextColorlinBufferAmount GNU Image Manipulation Program Page 96 of 421 Generated by docbook2odf ao e N E O O 2 S O xe a 2 xe o d 3 S o BERRREEE let TT TT Oe BERR RRR RRR BdefineWourlocalfvaria
298. mand e You can access this command from the image menubar through Select Sharpen Shrink The Shrink command reduces the size of the selected area by moving each point on the edge of the selection a certain distance further away from the nearest edge of the image toward the center of the selection Feathering is preserved but the shape of the feathering may be altered at the corners or at points of sharp curvature Activating the Command e You can access this command from the image menubar through Select Shrink Description of the Shrink dialog Shrink selection by 10 pixels El Shrink from image border TIRTS Grow The Grow command increases the size of a selection in the current image It works in a similar way to the Shrink command which reduces the size of a selection Activating the Command GNU Image Manipulation Program Page 233 of 421 Generated by docbook2odf y xe O N E O O 2 S O xe a 2 xe o d 3 S o e You can access this command from the image menubar through Select Grow Description of the Grow Selection dialog Grow selection by k j pixels m Cancel OK A Peculiarity of Rectangular Selections When you grow a rectangular selection the resulting selection has rounded corners The reason for this is shown in the image below siJ m G 20 pixels 1 a ae If you do not want rounded corners you can use the Rounded Rectangle
299. mand in the Compose filter section Activating the Command e You can access this command from the image menubar through Image Mode Compose Transform a Flip Horizontally Flip Verticalhy Rotate 90 degrees CW Rotate 90 degrees CCW Rotate 180 degrees Guillotine The items on the Transform submenu transform the image by flipping it rotating it or cropping it Activating the Submenu e You can access this submenu from the image menubar through Image Transform The Contents of the Transform Submenu The Transform submenu has the following commands e Flip Horizontally Flip Vertically e Rotate 90 CW Rotate 90 CCW Rotate 180 e Guillotine Flip Horizontally Flip Vertically You can flip the image or turn it over like a card by using the Flip Horizontally or Flip Vertically commands These commands work on the whole image To flip a selection use the Flip Tool To flip a layer use the functions of the Layer Transform menu or the Flip Tool Activating the Commands e You can access the horizontal flip command from the image menubar through Image Transform Flip Horizontally e You can access the vertical flip command from the image menubar through Image Transform Flip Vertically Rotation You can rotate the image 90 clockwise or counter clockwise or rotate it 180 by using the rotation commands on the Transform submenu of the Image menu These commands can be used to change between Portrait and
300. menu entry to be placed Therefore the appearance of this menu can be completely different for each user In practice though the appearance does not vary very much because most plug ins come with GIMP when it is installed and of course they are always in the same places in the menu Plug ins are not restricted to just the Filters menu a plug in can place entries in any menu Indeed a number of GIMP s basic functions for example Semi flatten in the Layer menu are implemented by plug ins But the Filters menu is the default place for a plug in to place its menu entries For general information on plug ins and how to use them see the section on Plug ins You can find information on the filters that are provided with GIMP in the Filters chapter For filters you install yourself please refer to the information which came with them Repeat Last The Repeat Last command performs the action of the most recently executed plug in again using the same settings as the last time it was run It does not show a dialog or request confirmation Please note that this command repeats the most recently executed plug in regardless of whether it is in the Filters menu or not GNU Image Manipulation Program Page 284 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Activating the Command e You can access this command from the image menubar through Filters Repeat filter e or by using
301. menu in any dockable dialog Add Tab Ihmages Grid List modes Previews size As in all dialogs with thumbnails the Tab menu gives you the possibility of adapting thumbnail display to your liking See Docking Using the Images dialog At the top of the dialog appears the name of the currently selected image if the Show Image Selection option is checked in Tab Menu Useless if you have selected Grid mode anyway the name Is displayed At center open images appear as a list or a grid according to the selected mode The current image is highlighted in list mode outlined in grid mode With a double click With a simple click on an image name you raise this image to the foreground of your screen With a simple click you select this image so that buttons can act on it e Raise this image s display The selected image appears at the foreground of your screen e Create a new display for this image Duplicates the image window not the image of the selected image e Delete this button is not working Document History dialog Document History The History Dialog displays the list of the documents you have opened in previous sessions It is more complete than the list you get with the Open Recent command Activate Dialog You can access to this dialog in different ways e From the toolbox menu and the image Menu bar File Open Recent Document History e From the image Menu bar Dialogs Document History GNU Image Manip
302. mmand e You can access this command from the image menubar through Select Float e or by using the keyboard shortcut Shift Ctrl L By Color The Select By Color command is an alternate way of accessing the Select By Color tool one of the basic selection tools You can find more information about using this tool in Select By Color Activating the Command e You can access this command from the tmage menubar through Select By Color e or by using the keyboard shortcut Shift O From Path The From Path command transforms the current path into a selection If the path is not GNU Image Manipulation Program Page 230 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o 4 d 0 S o closed the command connects the two end points with a straight line The original path is unchanged Activating the Command e You can access this command from the image menubar through Select From Path Ee In addition you can click on the Path to Selection button in the Path dialog to access the command e You can also use the keyboard shortcut Shift V Selection Editor Activating the Command e You can access this command from the image menubar through Select Selection Editor Description of the Selection Editor dialog window Selection Editor x The Selection to Path Advanced Settings dialog The Selection to Path Advanced Settings dialog contains a number of optio
303. mmercial use only and go to the download section e Download a prepared Windows distribution like gs650w32 exe or gs700w32 exe e Start the executable and follow the instructions of the installation procedure e Copy the executable gswin32c exe from the directory bin of the ghostscript installation to the Windows directory or any other directory that is contained in the PATH As an alternative advanced users can set an environment variable GS PROG to point to gswin32c exe e g c gs gsxX YY bin gswin32c exe Now you should be able to read PostScript files with GIMP Please note that you must not move the directories of ghostscript once the installation has finished Registry entries have been created that allow ghostscript to find libraries These instructions courtesy of http www kirchgessner net The format that is supposed to replace the GIF format and thus provide a solution to GIF s trademark and patent issues Indexed color grayscale and truecolor images are Supported plus an optional alpha channel PNG also uses compression but unlike JPEG it doesn t lose image information PSD is Adobe Photoshop s native file format and thus is comparable to XCFin complexity Gimp s ability to handle PSD files is sophisticated but limited some features of PSD files are not loaded and only PSD versions XX or less are supported Unfortunately Adobe has now made the Photoshop Software Development Kit which includes their file format Specifi
304. move tool and change the Affect option 2 Try to use the AltShift or AltCtrl keys to move the selection Moving a selection without emptying its Initial position is more complicated while pressing the Ctrl key move the mouse pointer a little bit then also press the Alt key then click and drag the selection This can be done more easily by using the Move tool in Selection mode Moving a selection automatically creates a floating layer floating selection See Floating selection The mouse pointer then looks like an anchor when it is outside of the selection This means that the selection will be permanently anchored at the place you choose when you click the mouse button As soon as this floating selection is created in the Layer dialog and you can create it with Selection Float you can use the keyboard arrow keys to move the selection horizontally or vertically Creating a Free Selection GNU Image Manipulation Program Page 58 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 v o Ww hn o c o When using the lasso to select an object some parts of the object and its proximity may be incorrectly either selected or not selected You can correct these defects by pressing the Shift or Ctrl keys while using the lasso Here is how to do it While pressing Shift draw the new border with the lasso and close the selection including a part of the first selection AS soon as you release th
305. n by clicking on it you define whether the channel is visible or not As a result of this visibility the view of the image changes in the image window and a white image becomes yellow if you remove the view of the blue because yellow is the complementary color for blue If you remove the view of the Alpha channel everything becomes transparent and nothing else than a grey checkerboard is visible The aspect of this virtual background can be changed in the Preferences The chain icon enables grouping of channels for operations on multiple channels Activated channels appear highlighted in blue in the dialog If you click on a channel in the list you toggle activation of the corresponding channel Disabling a color channel red blue or green has severe consequencies For instance if you disable the blue channel all GNU Image Manipulation Program Page 157 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o pixels from now on added to the image will not have blue component and so a white pixel will have the yellow complementary color Managing channels Under the channel list is a set of buttons allowing you to perform some basic operations on channel list Channels Menu g Edit Channel Attributes New Channel 4 Raise Channel Lower Channel Ct Duplicate Channel f Delete Channel IE Channel to Selection Et Add to Selection Selection masks Selection
306. n directions in the image lt uses a blur map Unlike other maps this filter doesn t use grey levels of this blur map Filter takes in account only gradient direction s Image pixels corresponding to solid areas of the map are ignored Options GNU Image Manipulation Program Page 380 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Effect Channel Effect Operator Convolve C Hue Derivative C With white noise C Saturation Gradient With source image Brightness Effect Image PF Untitled 2 8 ackground 4 Filter length p r 5 0 Noise magnitude SO 2 0 Integration steps 25 0 S Minimum value k 25 0 S Maximum value k 25 0 B e To create a blur check With Source Image Only Filter Length slider and perhaps Intregation Steps slider are useful e To create a texture check With White Noise All sliders can be useful pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 381 of 421 Generated by docbook2odf Rendering filters Render filters introduction Most Gimp filters act on a layer by transforming its contents but the filters in the Render group are a bit different They create patterns from scratch in most cases obliterating anything that was previously in the layer Some create random or noisy patterns others regular of fractal patterns and one Gfig is a g
307. n Dialog for other ways to access the Navigation Window If your mouse has a middle button click drag with it to span across the image Inactive Padding Area This padding area seperates the active image display and the inactive padding area so you re able to distinguish between them You cannot apply any Filters or Operations in generall on the inactive area Image Display The most important part of the image window is of course the image display or canvas It occupies the central area of the window surrounded by a yellow dotted line showing the image boundary against a neutral gray background You can change the zoom level of the image display in a variety of ways including the Zoom setting described below Image Window Resize Toggle If this button is pressed the image itself will be resized if the image window is resized Dialogs and Docking Docking Bars In GIMP 2 0 and 2 2 you have a lot of flexibility about the arrangement of dialog windows on your screen Instead of placing each dialog in its own window you can group them together using docks A dock is a container window that can hold a collection of persistent dialogs such as the Tool Options dialog Brushes dialog Palette dialog etc Docks cannot however hold image windows each image always has its own separate window They also can t hold non persistent dialogs such as the Preferences dialog or the New Image dialog Each dock has a set of docking bars as
308. n a gradient It can only be used on gradients you have created yourself or on a copy of a system gradient not on system gradients that come pre installed with GIMP This is a sophisticated tool that may take a bit of effort to understand The concept behind it is that a gradient can be decomposed into a series of adjoining segments with each segment consisting of a smooth transition GNU Image Manipulation Program Page 171 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o from the color on the left edge to the color on the right edge The Gradient Editor allows you to pack together any number of segments with any colors you want for the left and right edges of each segment and with several options for the shape of the transition from left to right How to Activate the Gradient Editor You can activate the Gradient Editor in several ways e By double clicking on the gradient stripe in the Gradient dialog e From the context menu you get by right clicking on the selected gradient name e By clicking on the Edit gradient button in the Gradient Dialog e From the Gradient Menu you get by clicking on the small triangle representing the Tab Menu in the Gradient Dialog Display Gradient Editor Menu Left Endpoint s Color Load Left Color From al Save Left Color To _ Right Endpoint s Color sai Load Right Color From Save Right Color To Blending Func
309. n any file format will cause the image to be considered not dirty even if the file format does not represent all of the information from the image pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 54 of 421 Generated by docbook2odf Drawing Simple Objects In this section you will learn how to create simple objects in Gimp It s pretty easy once you figure out how to do It Gimp provides a huge set of Tools and Shortcuts which most new users get lost in Drawing a Straight Line Let s begin by painting a straight line The easiest way to create a straight line is by using your favorite painting tool the mouse and the keyboard File Edit Select View Image Layer Tools Dialogs Filters S 100 Background 317 KB Create a new image Select your favorite painting tool or use the pencil if in doubt Select a foreground color but be sure that the foreground and background colors are different File Edit Select View Image Layer Tools Dialogs Filters S 100 Background 330 KB Create a starting point by clicking on the image display area with the left mouse button Your canvas should look similar to pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 55 of 421 Generated by docbook2odf File Edit Select View Image Layer Tools Dialogs Filters S Now hold down the Shift button on your keyb
310. n by keeping the image larger than that For this purpose the JPEG format is almost always a good choice e If you want to put the image on a web page or send it by email it is a good idea to make every effort to keep the file size as small as possible First scale the image down to the smallest size that makes it possible to see the relevant details bear in mind that other people may be using different sized monitors and or different monitor resolution settings Second save the image as a JPEG file In the JPEG save dialog check the option to Preview in image window and then adjust the Quality Slider to the lowest level that gives you acceptable image quality You will see in the image the effects of each change Make sure that the image is zoomed at 1 1 while GNU Image Manipulation Program Page 73 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 9 S o you do this so you are not misled by the effects of zooming See the File Formats section for more information Printing Your Photos This needs to be written EXIF Data Modern digital cameras when you take a picture add information to the data file about the camera settings and the circumstances under which the picture was taken This data is included in JPEG or TIFF files in a structured format called EXIF For JPEG files GIMP is capable of maintaining EXIF data if it is built appropriately it depends on a library
311. n filter accentuates edges but also any noise or blemish and it may create noise in graduated color areas like the sky or a water surface It competes with the Unsharp Mask filter which is more sophisticated and renders more natural results Options Unsharp Mask Parameter Settings Amount Threshold Lp o B Cancel Pox Overview This filter is found in Image gt Filters Enhance Unsharp Mask Out of focus photographs and most digitized images often need a sharpness correction This is due to the digitizing process that must chop a color continuum up in points with Slightly different colors elements thinner than sampling frequency will be averaged into an uniform color So sharp borders are rendered a little blurred The same phenomenon appears when printing color dots on paper The Unsharp Mask filter what an odd name sharpens edges of the elements without increasing noise or blemish It is the king of the sharpen filters Some scanners apply a sharpen filter while scanning It s worth disabling it so that you keep control on your image GNU Image Manipulation Program Page 331 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Options More information To prevent color distortion while sharpening Decompose your image to HSV and work only on Value Then Compose the image to HSV Go to Image Mode and click on Decompose Make sure the Decompose to Lay
312. nage fonts on Windows as well as Linux The instructions above work because Fontconfig by default uses the Windows fonts directory i e the same fonts that Windows uses Itself If for some reason your Fontconfig is set up differently you will have to figure out where to put fonts so that GIMP can find them in any case the fonts folder of your personal GIMP directory should work Font Problems Problems with fonts have probably been responsible for more GIMP 2 bug reports than any other single cause although they have become much less frequent in the most recent releases in the 2 0 series In most cases they have been caused by malformed font files giving trouble to Fontconfig If you experience crashes at startup when GIMP scans your font directories the best solution is to upgrade to a version of Fontconfig newer than 2 2 0 AS a quick workaround you can start gimp with the no fonts command line option but then you will not be able to use the text tool Another known problem is that Pango 1 2 cannot load fonts that don t provide an Unicode character mapping Pango is the text layout library used by GIMP A lot of symbol fonts GNU Image Manipulation Program Page 80 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o fall into this category On some systems using such a font can cause GIMP to crash Updating to Pango 1 4 will fix this problem and makes symbol fonts available
313. nd dirty adjustment in a few seconds but if the image is important and you want it to look as good as possible you will use one of the other tools In GIMP 2 4 a new way of operating this tool has been added by clicking the mouse inside the image and dragging while keeping the left mouse button down Moving the mouse vertically changes the brightness moving horizontally changes the contrast When you are Satisfied with the result you can either press the OK button on the dialog or hit the Return key on your keyboard Activate Tool The Brightness Contrast Tool can be called from an image menu Tools Color Tools Brightness Contrast If you find yourself using this tool often you can add it to the Toolbox using the Tools dialog Options Threshold Tool The Threshold tool transforms the current layer or the selection into a black and white image where white pixels represent the pixels of the image whose Value is in the threshold range and black pixels represent pixels with Value out of the threshold range You can use it to enhance a black and white image a scanned text for example or to create selection masks As this tool creates a black and white image the anti aliasing of the original image disappears If this poses a problem rather use the Levels tool Activate Tool The Threshold Tool can be called in the following order from the image menu Tools Color Tools Threshold hlor by clicking on the icon in Toolbox if
314. nd swap Otherwise go to the next step Is the disk that holds the OS swap faster or the same speed as the disk that holds the GIMP swap If slower take only the free RAM if faster or similar add free RAM and swap You now have a number be it just the free RAM or the free RAM plus the free OS swap Reduce it a bit to be on the safe side and that is the Tile Cache you could use as a good Start As you can see all is about checking the free resources and decide if the OS swap is worth using or will cause more problems than help There are some reasons you want to adjust this value though The basic one is changes in your computer usage pattern or changing hardware That could mean your assumptions about how you use your computer or the speed of it are no longer valid That would require a reevaluation of the previous steps which can drive you to a similar value or a completly new value Another reason to change the value is because it seems that GIMP runs too slowly while changing to other applications is fast this means that GIMP could use more memory without impairing the other applications On the other hand if you get complaints from other applications about not having enough memory then it may benefit you to not let GIMP hog so much of it If you decided to use only RAM and GIMP runs slowly you could try increasing the value a bit but never to use also all the free swap If the case is the contrary using both RAM and swap
315. ndo history If the image Is not clean that is tf you have changed it since the last time you saved it you are asked to confirm that you really want to close it Note that an image is marked as clean when it is saved to a file even if the file format chosen does not preserve all the information in the image so it is a good idea to think for a moment about what you are doing before closing an image If there is the slightest possibility that you will regret it it can t hurt to save a copy as an XCF file Activating the Command e You can access this command from the image menubar through File Close e or by using the keyboard shortcut Ctrl W e For most systems on which the GIMP runs you can also execute it by clicking ona Close button somewhere on the image window titlebar The location and appearance of this button are determined by the windowing system and the window manager If you close the image window as described above GIMP simply closes your image However if you close the Toolbox window by using the C ose button GIMP itself exits Quit The Quit command causes GIMP to close all images and exit If there are any open images which contain unsaved changes that is they are not marked as clean GIMP notifies you and displays a list of the unsaved images You can then choose which tmages you GNU Image Manipulation Program Page 220 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a
316. nerated by docbook2odf Temp folder e home bill gimp 2 1 tmp E Swap folder i nomejbily gimp 2 1 E This page allows you to set the locations for two important folders used by GIMP for temporary files The pages below it allow you to customize the locations searched for resources such as brushes etc see Data Folders for a description that applies to them You can change the folders here by editing the entries or by pressing the buttons on the right to bring up a file chooser window Data Folders pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 199 of 421 Generated by docbook2odf Brush Folders home bill gimp 2 1 brushes usrlocaligimp 2 1 share gimp 1 brushes GIMP uses several types of resources such as brushes patterns gradients etc for which a basic set are supplied by GIMP when it is installed and others can be created or downloaded by the user For each such resource type there is a Preference page that allows you to specify the search path the set of directories from which items of the type In question are automatically loaded when GIMP starts These pages all look very much the same the page for brushes is shown to the right as an example By default the search path includes two folders a system folder where items installed along with GIMP are placed and a personal folder inside your personal GIMP directory where items add
317. nipulation Program Page 126 of 421 Generated by docbook2odf Convolve Blur Sharpen j i j l Poi Ll a s x a rmm m i T a k a The Convolve tool uses the current brush to locally blur or sharpen your image Blurring with it can be useful if some element of your image stands out too much and you would like to soften it If you want to blur a whole layer or a large part of one you will probably be better off using one of the Blur Filters The direction of a brushstroke has no effect If you want directional blurring use the Smudge tool In Sharpen mode the tool works by increasing the contrast where the brush is applied A little bit of this may be useful but overapplication will produce noise Some of the Enhancement Filters particularly the Unsharp Mask do a much cleaner job of sharpening areas of a layer You can create a more sophisticated sharpening brush using the Clone tool To do this start by duplicating the layer you want to work on and run a sharpening filter such as Unsharp Mask on the copy Then activate the Clone tool and in its Tool Options set Source to Image source and Alignment to Registered Set the Opacity to a modest value such as 10 Then Ctrl click on the copy to make it the source image If you now paint on the original layer you will mix together where the brush is applied the Sharpened version with the unsharpened version Both blurring and sharpening work incrementally
318. ns Each of the scripts creates a new image filled with a particular type of pattern a dialog pops up that allows you to set parameters controlling the details of the appearance Some of these patterns are most useful for cutting and pasting others serve best as bumpmaps Palettes A palette is a set of discrete colors In GIMP palettes are used mainly for two purposes e They allow you to paint with a selected set of colors in the same way an oil painter works with colors from a limited number of tubes e They form the colormaps of indexed images An indexed image can use a maximum of 256 different colors but these can be any colors The colormap of an indexed image is called an indexed palette in GIMP Actually neither of these functions fall very much into the mainstream of GIMP usage it is possible to do rather sophisticated things tn GIMP without ever dealing with palettes Still they are something that an advanced user should understand and even a less advanced user may need to think about them in some situations as for example when working with GIF files GNU Image Manipulation Program Page 37 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 3 S o food Ega 240 RE Firecode 256 __ Gob 256 I crayblue 256 PA Grays 32 BE c ray violet 256 rele 256 When you install GIMP it comes supplied with Sever dozen predefined palettes and you can a
319. ns most of which you can set with either a slider bar or a text box There is alSo one check box These options are mostly used by advanced users They are e Align Threshold f two endpoints are closer than this value they are made to be equal e Corner Always Threshold If the angle defined by a point and its predecessors and successors is smaller than this it is a corner even if it is within Corner Surround pixels of a point with a smaller angle e Corner Surround Number of points to consider when determining if a point is a GNU Image Manipulation Program Page 231 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o corner or not e Corner Threshold If a point its predecessors and its successors define an angle smaller than this it is a corner e Error Threshold Amount of error at which a fitted spline is unacceptable If any pixel is further away than this from the fitted curve the algorithm tries again e Filter Alternative Surround A second number of adjacent points to consider when filtering e Filter Epsilon If the angles between the vectors produced by Filter Surround and Filter Alternative Surround points differ by more than this use the one from Filter Alternative Surround e Filter Iteration Count The number of times to smooth the original data points Increasing this number dramatically to 50 or so can produce vastly better results But if an
320. nsitions or gradients to indexed mode will often give poor results because it will turn the smooth gradients into a series of bands This method is also not recommended for photographs because it will make the image look coarse and grainy GNU Image Manipulation Program Page 75 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 v o ww in o c o Use the Convert Mode Dialog to convert your RGB image to indexed mode After you have converted the image to indexed mode you are once again able to save your image in PNG format Saving Images with Transparency There are two different approaches used by graphic file formats for supporting transparent image areas simple binary transparency and alpha transparency Simple binary transparency is supported in GIF format Here one color from the indexed color palette is marked as the transparent color Aloha transparency is supported in PNG format Here the transparency information is stored in a separate channel the Alpha channel There is usually no need to save images in GIF format any more because PNG supports all the features of GIF and offers additional features e g alpha transparency Nevertheless this format is still used for animations First of all we will use the same image as in the previous tutorials Wilber the GIMP mascot To save an image with alpha transparency you must have an alpha channel To check if the image has
321. nus there is a dotted line at the top of It By clicking on this dotted line you detach the menu under it and it becomes a separate window F Paste as Mew From Clipboard Screen Shot TWAIN GNU Image Manipulation Program Page 204 of 421 Generated by docbook2odf y xe O N E O O 2 S O xe a 2 xe o d 3 S o Acquire x H Paste as New From Clipboard Screen Shot TWAIN Detached submenus originating from the Toolbox are only visible when the Toolbox is active Detached submenus originating from the Image window are actually independent They are always visible their functions always apply to the current image and they persist when all of the images are closed You can close a detached submenu by clicking on the dotted line again or closing the window from the window manager on your computer often by clicking on an X icon in the upper right corner of the window pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 205 of 421 Generated by docbook2odf Toolbox File Menu Toolbox File Menu mie Xtns Help New Open Open Location Open Recent Acquire Preferences Dialogs i Quit ctrl Q The Toolbox is the heart of the GIMP It contains the most commonly used controls and the highest level menus Two of the menus File and Help can alSo be accessed from the menubars located above ea
322. nvas border Activating the Command e You can access this command from the tmage menubar through Image Canvas Size Description of the Canvas size dialog GNU Image Manipulation Program Page 250 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Canvas Size Width Ed Z5 as ol Height 138 2 b 7 200 138 pixels 72 dpi T Center Bue CC Help a gl Reset Cancel Pa Resize The Offset values are used to place the image on the canvas The preview window displays the image in a frame with a thin border When the canvas is smaller than the image the preview window shows it in a frame with a thin black border When you click on the Resize button the canvas is resized but the pixel information and the drawing scale of the image are unchanged If the layers of the image did not extend beyond the borders of the canvas before you changed its size there are no layers on the part of the canvas that was added by resizing it Therefore this part of the canvas is transparent and displayed with a checkered pattern and it is not immediately available for painting You can either flatten the image in which case you will get an image with a single layer that fits the canvas exactly or you can use the Layer to Image Size command to resize only the active layer without changing any other
323. ny Modified Version You may combine the Document with other documents released under this License under the terms defined in section 4 above for modified versions provided that you include in the combination all of the Invariant Sections of all of the original documents unmodified and list them all as Invariant Sections of your combined work in its license notice and that you preserve all their Warranty Disclaimers The combined work need only contain one copy of this License and multiple identical Invariant Sections may be replaced with a single copy If there are multiple Invariant Sections with the same name but different contents make the title of each such section unique by adding at the end of it in parentheses the name of the original author or publisher of that section if known or else a unique number Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work In the combination you must combine any sections Entitled History in the various original documents forming one section Entitled History likewise combine any sections Entitled Acknowledgements and any sections Entitled Dedications You must delete all sections Entitled Endorsements You may make a collection consisting of the Document and other documents released under this License and replace the individual copies of this License in the various documents with a single copy that is included in
324. o e You can access this command from the image menubar through Layer Transparency Color to Alpha Semi flatten The Semi Flatten command is described in the Semi flatten filter chapter The command is useful when you need an anti aliased image with indexed colors and transparency Activating the Command e You can access this command from the image menubar through Layer Transparency Semi flatten Threshold Alpha This command converts partial transparency into all or none transparency by applying a user specified cutoff threshold to the layer s alpha channel It only works on alpha channel possessing layers from RGB images if the image is Grayscale or Indexed or the layer lacks an alpha channel the menu entry will be insensitive If Keep transparency has been toggled on in the Layers dialog the command will show an error message and refuse to operate Activate Dialog e This operation can be accessed from an image menubar as Layer Transparency Threshold Alpha Dialog window description Thresho M O iam 27 Alpha to Selection The Alpha to Selection command creates a selection in the image from the active layer s aloha channel which encodes transparency Opaque areas are fully selected transparent areas are unselected and translucent areas are partially selected This selection replaces the existing selection The alpha channel itself is not changed The other commands in this group of operations are sim
325. o gimp 2 2 modules Y Creating folder home marco gimp 2 2 environ Y Creating folder home marco gimp 2 2 scripts Y Creating folder home marco gimp 2 2 templates Y Creating folder home marco gimp 2 2 themes Y Creating folder fhome marco gimp 2 2 tmp Y froastina faldar fAnama marea aimna 0 Bitaal_antiance af xe O N E O e 2 S O xo a 2 xe o hn o S GNU Image Manipulation Program Page 11 of 421 Generated by docbook2odf 4 Setting your memory usage is not an easy thing So much depends on what your needs are for the GIMP and what hardware you have to work with You have two options at this point Go with the default value the developers have set here or determine the best value A brief tile cache explanation might help you determine this value The tile cache information might also be helpful to you if you are encountering memory problems when using the GIMP On a Unix system tmp might be a good place for the swap For optimal GIMP performance some settings may have to be adjusted GIMP uses a limited amount of memory to store image data the so called Tile Cache You should adjust its size to fit into memory Consider the amount of memory used by other running processes Tile cache size 128 l Megabytes Allimage and undo data which doesn t fit into the Tile Cache will be written to a swap file This file should be located on a loca
326. o allow for a buffer we need to center the text within the image This is done by moving it to the x y coordinates of theBuffer theBuffer added this line after resizing the layer and the image EEEEHEEE gimp layer set offsetsHtheTexti amp theBufferitheBuffer BEREEE Go ahead and save your script and try it out after refreshing the database All that is left to do is return our image the layer and the text layer After displaying the image we add this line BERRRRRE lL isti8thelImagelitheLayeritheText LT TTT This is the last line of the function making this list available to other scripts that want to use it To use our new text box script in another script we could write something like the following BERRRREE set BtheResult script fu text boxil eee SomeEtext i See Charter E 30 eee OROCO TT TT TTT TTT Moe eee BERR RERE BERRRREE Gimp image flatten carlltheResult LT TTT Congratulations you are on your way to your Black Belt of Script Fu GNU Image Manipulation Program Page 98 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o Creating Shortcuts to Menu Functions Many functions which are accessible via the image menu have a default keyboard Shortcut You may want to create a new shortcut for a command that you use a lot and doesn t have one or more rarely edit an existing shortcut There are two methods for
327. oard and move the mouse away from the starting point you created You ll see a thin line indicating how the line will look File Edit Select View Image Layer Tools Dialogs Filters 100 Background 415 KB If you re satisfied with the direction and length of the line click the left mouse button again to finish the line The Gimp displays a straight line now If the line doesn t appear check the foreground and background colors and be sure that you kept the Shift key pressed while painting You can keep creating lines by continuing to hold the Shift key and creating additional end points Creating a Basic Shape Drawing shapes is not the main purpose for using GIMP However you may create shapes by either painting them using the technique described in or by using the selection tools Of course there are various other ways to paint a shape but we ll stick to the easiest ones here So create a new Image and check that the foreground and background colors are different pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 56 of 421 Generated by docbook2odf File Edit Select View Image Layer Tools Dialogs Filters S 100 New Layer 495 KB Cancel Basic shapes like rectangles triangles or ellipses can be created using the selection tools This tutorial uses a rectangular selection as an example So choose the rectangular selection tool and create a new selection
328. ocation URI ee Help _ Cancel Bopen Open Recent Selecting Open Recent displays a submenu with the names of the files that you have opened recently in GIMP Simply click on a name to reopen it You can customize the number of items shown in the menu by changing the Open Recent Menu Size value in the Interface page of the Preferences dialog See the Document History dialog at the bottom of the Open Recent submenu if you cannot find your image Activating the Dialog e This menu item can be accessed from the toolbox or image menus as File Open Recent e or by using the keyboard shortcut Ctrl O Open as Layer The Open Image as layer dialog is identical to the Open Image dialog With this dialog you can open an image file which is added to the current image as the top layer in the stack Activating the Dialog e This command can be accessed from the image menu bar as File Open as layer e The default shortcut is Ctrl Alt O Save The Save command saves your image to disk If you have already saved the image the previous image file is overwritten with the current version If you have not already saved the image the Save command does the same thing as the Save As command GIMP opens the File Save dialog so that you can choose the data format the path and the filename of the new image file If the image was previously saved it is automatically saved to the same location using the same file name file typ
329. ocbook2odf Files The GIMP is capable of reading and writing a large variety of graphics file formats With the exception of GIMP s native XCF file type file handling is done by plug ins Thus it is relatively easy to extend GIMP to new file types when the need arises Not all file types are equally good for all purposes This part of the documentation should help you understand the advantages and disadvantages of each type Creating new Files You can create new files in GIMP by using the following menuitem File New This opens the Create a new image dialog where you can modify the initial width and height of the file or using the standard values More information about this dialog can be found in Opening Files There are several ways of opening an existing image in GIMP e Open File The most obvious is to open it using a menu by choosing File Open from either the Toolbox menu or an image menu This brings up a File Chooser dialog allowing you to navigate to the file and click on its name This method works well if you know the name of the file you want to open and where it is located It is not so convenient if you want to find the file on the basis of a thumbnail T i Home s gimp help 2 images A Filesystem E tool options 09 27 2004 mm images using 12 20 2004 png caution png 11 28 2003 pos ter 200 4 ES example png 03 06 2004 Ea gimp splash png EE home png 03 06 2004 link png 03 06 2004 gimp sp
330. of an action by repeatedly undoing and redoing it This is usually very quick and does not consume any extra resources or alter the undo history so there is never any harm in it lf you undo one or more actions and then operate on the image in any way except by using Undo or Redo it will no longer be possible to redo those actions they are lost forever The solution to this if it creates a problem for you is to duplicate the image and then operate on the copy Not the original because the undo redo history is not copied when you duplicate an image If you often find yourself undoing and redoing many steps at a time it may be more GNU Image Manipulation Program Page 27 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o convenient to work with the Undo History dialog a dockable dialog that shows you a small sketch of each point in the Undo History allowing you to go back or forward to that point by clicking Undo is performed on an image specific basis the Undo History is one of the components of an image GIMP allocates a certain amount of memory to each image for this purpose You can customize your Preferences to increase or decrease the amount using the Environment page of the Preferences dialog There are two important variables the minimal number of undo levels which GIMP will maintain regardless of how much memory they consume and the maximum undo memory
331. of on or off A black and white newspaper uses only black ink yet pictures in newspapersappear to be constructed of grey tones Furthermore there are techniques used to achieve greater success in dithering The GIMP can use the Floyd Steinberg dithering technique for example This dithering method is simply put a mathematical way of clustering the pixels to accomplish better results thanother dithering methods Of course there are always exceptions and there are many different dithering models that are in usetoday A way that an image is written You should select a file format which is suitable for your Situation JPEG and PostScript are examples of file formats Feathering is a process by which the edges of a region are softly blended with the background Floating selections are similar in function to layers except that floating selections must be anchored before work can resume on any other layers in the image While a selection is floating any number of functions can be used to alter the image data contained within the float There are two methods available for anchoring a float The first and most useful is to change the float into a new layer This is achieved by creating a new layer while the float is active The second method involves anchoring the float to an already existing layer This is done by clicking anywhere on the image except on the float Doing so will merge the float with the background layer Any pasted selection w
332. of the time by default it shows which part of the image Is currently active and the amount of system memory that the image is consuming You can customize the information that appears here by changing your Preferences When you perform time consuming operations the status area changes temporarily to show what operation is being performed and its state of progress Cancel Button At the lower right corner of the window appears the Cancel button If you start a complex time consuming operation most commonly a plug in and then decide while it is being computed that you didn t really want to do it after all this button will cancel it immediately There are a few plug ins that respond badly to being canceled possibly leaving corrupted GNU Image Manipulation Program Page 16 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o pieces of images behind Navigation control This is a small cross shaped button at the lower right corner of the image display Clicking on it and holding the left mouse button down brings up a window showing a miniature view of the image with the displayed area outlined You can pan toa different part of the image by moving the mouse while keeping the button depressed For large images of which only a small part is displayed the navigation window is often the most convenient way of getting to the part of the image you are looking for See Navigatio
333. ok2odf pe O N E O O 2 S O xe a 2 xe o hn S o outlined in the operating system specific documentation for the individual GIMP package The most fundamental operations provided by a clipboard interface allow for Cut Copy and Paste Cut is used to denote the removal of an item that is sent to the clipboard Copy leaves the item in the document and copies it to the clipboard Paste copies to the document whatever happens to be in the clipboard The GIMP will make an intelligent decision about what to paste depending upon the target If the target is a canvas then paste operation will use the image clipboard If the target is a text entry box then the paste operation will use the text clipboard Dithering refers to the math and voodoo involved in rendering an image that has few colors seem like it has many Dithering is accomplished in different ways depending on the output device and the program One particularly effective method Is clustering pixels of color together in an attempt to simulate another color This is achieved by the human eye and the tendency for it to mix colors while viewing complex color patterns A common dithering effect is seen on television screens or in newspaper print From a distance the images seem to be constructed of many varied colors or shades but upon closer inspection this is certainly not the case A color television uses only three colors clustered together in various states
334. olor shown in the Background part of the Color Area of the Toolbox The color is also shown to the left of the menu entry If some areas of the image are only partially selected for example as a result of feathering the selection they are filled in proportion to how much they are selected Please note that if the image has no selection the whole active layer is filled Activating the Command e You can access this command from the image menubar through Edit Fill with BG Color e or by using the keyboard shortcut Ctrl You can also fill a selection by click and dragging from the Toolbox background color Fill with Pattern The Fill with Pattern command fills the image s selection with the pattern shown in the Brush Pattern Gradient area of the Toolbox The pattern is also shown to the left of the menu entry If some areas of the image are only partially selected for example as a result of feathering the selection they are filled in proportion to how much they are selected You can select another pattern by using the Pattern Dialog GNU Image Manipulation Program Page 226 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Please note that if the image has no selection the whole active layer is filled Activating the Command e You can access this command from the image menubar through Edit Fill with Pattern r e or by using the keyboard shortcut Ctrl
335. olour encodings are also used The green component sometimes has more bits that the other two to cater for the human eye s greater discrimination in this component Each image is divided up into separate channels and then recombined before being sent to the output device An output device is most usually a screen The channels that are used when rendering images to a screen are Red Green and Blue Other output devices may use different channels Channels can be useful when working on images that need adjustment to one particular color If for example the removal of red eye is the goal work on the Red channel is most obviously a ready solution Channels can be seen as masks that allow or restrict the output of the color that the channel represents By running filters against this channel information many varied and subtle effects can be put in to play by the experienced GIMP user Clipboard is the term used to describe a temporary area of memory that Is used to transfer data between applications or documents The GIMP uses slightly different clipboard approaches when used under different operating systems Under Linux XFree the XFree clipboard is used for text and The GIMP internal image clipboard is used for images that are being transferred between image documents When The GIMP is used with other operating systems differences may be apparent Any differences should be GNU Image Manipulation Program Page 401 of 421 Generated by docbo
336. on in the database about the functions provided PDF Portable Document Format was developed by Adobe to address some of the deficiencies of Postscript most importantly PDF files tend to be much smaller than equivalent Postscript files As with Postscript Gimp s support of the PDF format is via GNU Image Manipulation Program Page 405 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Ghostscript Created by Adobe PostScript is a page description language mainly used by printers and other output devices It s also an excellent way to distribute documents Gimp does not Support Postscript directly it depends on a powerful free software program called Ghostscript The great power of Postscript is its ability to represent vector graphics lines curves text paths etc in a resolution independent way Postscript is not very efficient though when it comes to representing pixel based raster graphics For this reason postscript is not a good format to use for saving images that are later going to be edited using Gimp or another graphics program Linux distributions almost always come with Ghostscript already installed not necessarily the most recent version For other operating systems you may have to install it yourself Here are instructions for installing it on Windows e Go to the Ghostscript project page on Sourceforge e Look for package gnu gs or ghostscript non co
337. onality that permits you to quickly choose a brush from the list if you clic on the button present on the right botton of the popup you open the real brush dialog Note that depending on your Preferences a brush selected with the popup may only apply to the currently active tool not to other paint tools See the Tool Option Preferences section for more information Using the brush dialog The functions performed by these buttons can also be accessed from the dialog pop up menu activated by right clicking anywhere in the brush grid list or by choosing the top item Brushes menu from the dialog Tab menu Brush Editor GNU Image Manipulation Program Page 168 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Brush Editor E The Brush Editor allows you either to view the brush parameters of a brush supplied by GIMP and you can t change them or to create a custom brush from a geometrical shape a circle a square a diamond This editor has several elements The dialog bar As with all dialog windows a click on the small triangle prompts a menu allowing you to set the aspect of the Brush Editor The title bar To give a name to your brush The preview area Brush changes appear in real time in this preview Settings Patterns dialog Patterns Leopard b4 x O2 In GIMP a pattern is a small image used to fill areas by placing copies of side by side See the
338. ons that affect the image display without altering the underlying image data The most important example is zooming There are however exceptions toggling QuickMask on or off can be undone even though it does not alter the image data There are a few important actions that do alter an image but cannot be undone Filters and other actions performed by plugins or scripts can be undone just like actions implemented by the GIMP core but this requires them to make correct use of GIMP s Undo functions If the code Is not correct a plugin can potentially corrupt the Undo History so that not only the plugin but also previous actions can no longer properly be undone The plugins and scripts distributed with GIMP are all believed to be set up correctly but obviously no guarantees can be given for plugins you obtain from other sources Also even if the code Is correct canceling a plugin while it is running can sometimes leave the Undo History corrupted so it is best to avoid this unless you have accidentally done something whose consequences are going to be very harmful Grids and Guides You will probably have it happen many times that you need to place something in an image very precisely and find that it is not easy to do using a mouse Often you can get better results by using the arrow keys on the keyboard which move the affected object one pixel at a time or 25 pixels if you hold down the Shift key but GIMP also provides you with two othe
339. ont specified in the script dialog hasn t been installed on your system So please check the information in the dialog before blaming the script There are two kinds of Script Fus standalone scripts and image dependent scripts You will find the standalone variants under Xtns Script Fu Type of Script in the main toolbox menu and the image dependent scripts are placed under Script Fu Type of Script in the image menu We will not try to describe every script in depth Most Script Fus are very easy to understand and use At the time of this writing the following types are installed by default e Patterns e Web page themes e Logos e Buttons e Utils GNU Image Manipulation Program Page 48 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 9 S o e Make Brush e MISC These are scripts that perform operations on an existing image In many ways they are like the plug ins in the Filters menu The following script groups are installed by default e Alchemy e Alpha to logo e Animators e Decor e Render e Selection e Shadow e Stencil Ops e Utils pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 49 of 421 Generated by docbook2odf Chapter Using GIMP as a Beginner pe O N E O O 2 S O xe a 2 xe o 4 G d 0 S o GNU Image Manipulation Program Page 50 of 421 Generated by d
340. ood often they are a bit odd Stretch HSV operates on layers from RGB and Indexed images If the image is Grayscale the menu entry will be insensitive Activate Dialog e This command can be accessed from an image menubar as Layer Colors Auto Stretch HSV Normalize This command scales brightness values across the active layer so that the darkest point becomes black and the brightest point becomes as bright as possible without altering its hue This is often a magic fix for images that are dim or washed out Normalize works on layers from RGB Grayscale and Indexed images Activate Dialog e This command can be accessed from an image menubar as Layer Color Auto Normalize The Mask Submenu hae Add Layer Mask Apply Layer Mask in Delete Layer Mask E Mask to Selection GT Add to Selection The Mask submenu of the Layer menu contains commands which work with masks creating a mask applying a mask deleting a mask or converting a mask into a selection See the Layer Masks section for more information on layer masks and how to use them Activating the Submenu e You can access this submenu from the image menubar through Layer Mask The Contents of the Mask Submenu The Mask submenu contains the following commands GNU Image Manipulation Program Page 268 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Add Layer Mask The Add Layer Mask command adds a
341. ook2odf Window Management Window Manager Hints Hint for the toolbox Normal window Hint for the docks Normal window Focus jy Activate the focused image Window Positions Z Save window positions on exit Save Window Positions Now Reset Saved Window Positions to Default Values This page lets you customize the way windows are handled in GIMP You should note that GIMP does not manipulate windows directly instead it sends requests to the window manager i e to Windows if you are running in Windows to Metacity if you are running in a standard Gnome setup in Linux etc Because there are many window managers and not all of them are well behaved it cannot be guaranteed that the functions described here will actually work as described However if you are using a modern standards compliant window manager they ought to Options Environment xe e N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 197 of 421 Generated by docbook2odf Environment Resource Consumption Minimal number of undo levels E gi Maximum undo memory Tile cache size Maximum new image size File Saving Confirm closing of unsaved images Size of thumbnail files Normal 128128 Options Folders pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o GNU Image Manipulation Program Page 198 of 421 Ge
342. ool in the following order from the image menu Tools Color Tools Hue Saturation Options GNU Image Manipulation Program Page 139 of 421 Generated by docbook2odf y xe O N E O O 2 S O xe a 2 xe o d 3 S o Adjust Hue Lightness Saturation Background 2 Untitled Select Primary Color to Modify Modify Selected Color Hue a O LP fo Lightness fo Saturation fo Reset Color F Preview Reset A Cancel Pox Colorize Tool The Colorize tool renders the active layer or selection into a greyscale image seen through a colored glass See HSV Color Model for Hue Saturation Luminosity Activate Tool The Colorize Tool can be called in the following order from the image menu Tools Color Tools Colorize Options af Colorize the Image Background 2 Untitled Preview Reset M Cancel Pox Brightness Contrast tool The Brightness Contrast tool adjusts the brightness and contrast levels for the active layer or selection This tool is easy to use but relatively unsophisticated The Levels and Curve tools allow you to make the same types of adjustments but also give you the GNU Image Manipulation Program Page 140 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o ability to treat bright colors differently from darker colors Generally speaking the BC tool is great for doing a quick a
343. or Input Levels 39 l 2 86 255 Output Levels 32 l 255 E F Hold Intensity M Original Intensity Use Subcolors Smooth Samples sJ Reset Get Sample Colors X Close Apply xe O N E O O 2 S O xe a 2 xe o hn o S o GNU Image Manipulation Program Page 304 of 421 Generated by docbook2odf Overview KAA Ae zE E a FER oTa a earned e f p if I S H a BU SEER REE This filter is found in Filters Colors Map Sample Colorize This filter allows you to colorize old black and white images by mapping a color source image or a gradient against it Your gray tone image must be changed to RGB before using this filter Image Image gt Mode gt RGB Options The filter window is divided into two parts Destination on the left Sampling on the right Gradient Map Overview GNU Image Manipulation Program Page 305 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o Ww hn o c o This filter uses the current gradient as shown in the Brush Pattern Gradient area of the Toolbox to recolor the active layer or selection of the image to which the filter is applied To use it first choose a gradient from the Gradients Dialog Then select the part of the Image you want to alter and activate the filter by choosing Filters Colors Map Gradient Map from the tmage menu The filter runs automatically without showing any dialog or requiring
344. or multiple layers For this reason saving images as JPEG often requires them to be exported GNU Image Manipulation Program Page 403 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Image Preview Preview in image window Size unknown Parameter Settings 0 85 Quality _t 0 00 Smoothing Lt Restart markers 1 Restart frequency rows _t M Optimize Progressive lf Force baseline JPEG Readable by all decoders WW Save EXIF data Subsampling 2x2 1x1 1x1 DCT method Speed quality tradeoff Integer Image comments Created with The GIMP When you save a file in JPEG format you get a dialog that allows you to set the Quality level which ranges from 1 to 100 Values above 95 are generally not useful though The default quality of 85 usually produces excellent results but in many cases It Is possible to set the quality substantially lower without noticably degrading the image You can test the effect of different quality settings by checking Show Preview in image window in the JPEG dialog Checking this causes each change in quality or any other JPEG parameter to be visualized in the image display This does not alter the image though it reverts back to its original state when the JPEG dialog is closed The JPEG algorithm is quite complex and involves a bewildering number of options whose meaning Is beyond the scope of this documentation Unless you are
345. or to use a custom color which can be set using the color button for Custom padding color Image Window Title and Statusbar pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 192 of 421 Generated by docbook2odf Image Title amp Statusbar Format Image Title Format Dt f tp i Ft mL Mowe oh Custom w Dt f p Mi Ft 9L vwx oh Standard gaf Sop wai Sot Show zoom percentage of 6p ai Sot voz 9 Show zoom ratio dgf 0p 94i Sot Fad Sos Show image size cot Sop Sot awx 3oh Show memory usage af 36p 6i 26t Som Image Statusbar Format on 4am Custom van 2am Standard Sof Sop wai ot Show zoom percentage of p oi Sot Mz 90 Show zoom ratio Vot Sop oi Sot Fad 9s Show image size Sot Sop 01 Sot awx ah Show memory usage f 36p i 2t Som Choosing a Format You can choose among several predesigned formats or you can create one of your own by writing a format string in the entry area Here is how to understand a format string anything you type Is shown exactly as you type it with the exception of variables whose names all begin with Here is a list of the variables you can use Display o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 193 of 421 Generated by docbook2odf Transparency Transparency type Mid Tone Checks Ba Check size
346. ors from the unblurred area into the blurred area To help you pick the one you want we will illustrate what each does when applied to the image shown at right These are of course only examples most of the filters have parameter settings that allow you to vary the magnitude or type of blurring The most broadly useful of these is the Gaussian blur Don t let the word Gaussian throw you this filter makes an image blurry in the most basic way It has an efficient implementation that allows it to create a very blurry blur tn a relatively short time If you only want to blur the image a little bit to soften it as it were you might use the simple Blur filter In Gimp 2 2 this runs automatically without creating a dialog The effect is subtle enough that you might not even notice it but you can get a stronger effect by repeating it In Gimp 2 0 the filter shows a dialog that allows you to set a repeat count If you want a strong blurring effect this filter is too slow to be a good choice use a Gaussian blur instead The Selective Blur filter allows you to set a threshold so that only pixels that are similar to each other are blurred together It is often useful as a tool for reducing graininess in photos without blurring sharp edges In the example note that the graininess of the background has been reduced The implementation is much slower than a Gaussian blur GNU Image Manipulation Program Page 288 of 421 Genera
347. ort click on the link Create a New Attachment and follow the directions But please don t do this unless you think the attachment is really going to be useful and if you need to attach a screenshot don t make it any larger than necessary Bug reports are likely to remain on the system for years so there is no sense in wasting memory GNU Image Manipulation Program Page 415 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o What Happens to a Bug Report after you Submit it At any time after it is submitted a bug report has a Status that describes how it is currently being handled Here are the possible values of Status and what they mean Copyright C 2000 2001 2002 Free Software Foundation Inc 59 Temple Place Suite 330 Boston MA 02111 1307 USA Everyone is permitted to copy and distribute verbatim copies of this license document but changing it is not allowed The purpose of this License is to make a manual textbook or other functional and useful document free in the sense of freedom to assure everyone the effective freedom to copy and redistribute it with or without modifying it either commercially or noncommercially Secondarily this License preserves for the author and publisher a way to get credit for their work while not being considered responsible for modifications made by others This License is a kind of copyleft which means that derivative wo
348. ou can complete the operation either by clicking inside the crop region or by pressing the Crop or Resize buttons on the dialog See below for what these mean If you find that the dialog gets in your way more than it helps you you can prevent it from appearing by holding down the Shift key when you first click on the image Working this way means altering the crop region by dragging the corners and executing the operation by clicking inside the image pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 132 of 421 Generated by docbook2odf Activate Tool e The Crop Tool can be called way the following way from the image menu Tools Transform Tools Crop and Resize e The Tool can also be called by clicking the tool icon A different and quicker way to crop selections is using the Image Crop Image function in the Image menu Key modifiers Defaults Options Tool Toggle lt Ctri gt Crop C Resize Current layer only Allow enlarging lt Alt gt Keep aspect ratio lt Shift gt Rotate Tool Overview This tool is used to rotate the active layer a selection or a path When you click on the image or the selection with this tool a grid or an outline is Superimposed and a Rotation Information dialog is opened There you can set the rotation axis marked with a point and the rotation angle You can do the same by dragging the mouse pointer on the
349. ou try to close the image created without first saving the file Gimp will ask you if you want to save your work before you close the image It asks this because the image Is marked as dirty or unsaved In the case of our script this is a nuisance for the times when we simply give it a test run and don t add or change anything in the resulting image that is our work is easily reproducible in such a simple script so it makes sense to get rid of this dirty flag To do this we can clear the dirty flag after displaying the image BERRRREE gimp image clean alllitheImage PTT TT This will set dirty count to 0 making it appear to be a clean image Whether to add this line or not is a matter of personal taste use it In scripts that produce new images where the results are trivial as in this case If your script is very complicated or if it works on an existing image you will probably not want to use this function Extending The Text Box Script Handling Undo Correctly When creating a script you want to give your users the ability to undo their actions should they make a mistake This is easily accomplished by calling the functions gimp undo push group start and gimp undo push group end around the code that manipulates the image You can think of them as matched statements that let Gimp know when to start and stop recording manipulations on the image so that those manipulations can later be undone If you are creating a new i
350. ou work with a tool that has a Brush option while pressing the Shift key the brush size will vary by using the mouse wheel This change will be visible in real time in the brush area of the Toolbox and in the Brush Dialog By enabling the Main Keyboard tab you can in the same way assign an action to the events of the keyboard arrow keys Actions are not removed from the window when you delete the brush You have to delete them manually by clicking on the Delete button after selecting them pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 102 of 421 Generated by docbook2odf Chapter Toolbox pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 103 of 421 Generated by docbook2odf The Toolbox The GIMP provides a comprehensive toolbox in order to quickly perform basic tasks such as making selections or drawing paths The many tools contained within The GIMP s toolbox are discussed in detail here The GIMP has a diverse assortment of tools that let you perform a large variety of tasks The tools can be thought of as falling into five categories Selection tools which specify or modify the portion of the image that will be affected by subsequent actions Paint tools which alter the colors in some part of the image Transform tools which alter the geometry of the image Color tools which alter the distri
351. ple output pixels in order to approximate the darkness of the original image tn that cell Obviously a large cell size results in a heavy loss tn resolution The spots in the cells typically start off as circles and grow to be diamond shaped This change in shape is controlled by a spot function By using different spot functions the evolution in the shape of the spots as the cell goes from fully black to fully white may be controlled GNU Image Manipulation Program Page 354 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o Options More explanations illustrative diagrams a gallery and a tutorial are to be found on the plug in author site http www cl cam ac uk and1000 newsprint You are strongly encouraged to visit it since halftoning is a large and complex area Here is an example from the author s gallery Video Parameter Settings RGB Pattern Type O Staggered Additive C Large staggered Wide striped Long staggered i 3x3 Large 3x3 Hex Dots a Cancel Overview This filter is found in Image gt Filters Distorts Video Apply low dotpitch RGB simulation to the specified drawable Options Value Propagate pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 355 of 421 Generated by docbook2odf Parameter Settings Lower Threshold tz fo g More Black Smaller Value e kt
352. press and hold the left mouse button while you move the mouse to another position in the image illustrated in figure The selection is created when you release the mouse button For more information about key modifiers see selection tools File Edit Select View Image Layer Tools Dialogs Filters S After creating the selection you can either create a filled or an outlined shape with the foreground color of your choice If you go for the first option choose a foreground color and fill the selection with the bucket fill tool If you choose the latter option create an outline by using theStroke selection menu item from the Edit menu If you re satisfied with the result remove the selection pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 57 of 421 Generated by docbook2odf Creating and Using Selections Moving a Selection After creating a rectangular elliptic or free selection or when you are using the Magic wand the default mouse pointer is the moving cross Click and drag then allows you to move the selection and its contents while the initial position remains empty If you only want to move the selection border and not its contents then press the Alt key and click and drag the selection Sometimes the Alt key is used by the window manager and you move the image window instead of the selection If this is the case you have two possibilities 1 Select the
353. r you can see the image as if you were suffering from cataracts You may have to increase the contrast of the image so that your grandmother can see it well In most cases only very low values of the Contrast Cycles parameter are of interest Higher values create a side effect which doesn t interest us here if you increase the luminosity value above 255 the complementary color appears If you are interested in this subject you can browse the Web for contrast sensitivity Color Proof The various systems for reproducing colors cannot represent the infinity of colors available Even if there are many colors in common between the various systems and nature some of the colors will not be the same The gamut ts the color range of a system Color Profiles allow you to compensate for these differences Before you print an image it may be useful for you to see if you will get the result you want by applying a profile The Color Proof filter shows you how your image will look after a color profile has been applied GNU Image Manipulation Program Page 241 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Available Filters Active Filters m Color Deficient Vision gt B Color Proof Gamma Contrast Color Proof Configure selected filter Color Proof Intent Perceptual Profile m Black Point Compensation Greset You can apply the filter you h
354. r aids to make positioning easier grids and guides GNU Image Manipulation Program Page 28 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o 4 d 0 S o File Edit Select View Image Layer Tools The Image Grid Each image has a grid It is always present but by default it is not visible until you activate it by toggling View Show Grid in the image menu If you want grids to be present more often than not you can change the default behavior by checking Show grid in the Image Window Appearance page of the Preferences dialog Note that there are separate settings for Normal Mode and Fullscreen Mode The default grid appearance set up when you install GIMP consists of plus shaped black crosshairs at the grid line intersections with grid lines spaced every 10 pixels both vertically and horizontally You can customize the default grid using the Default Image Grid page of the Preferences dialog If you only want to change the grid appearance for the current image you can do so by choosing Image Configure Grid from the image menu this brings up the Configure Grid dialog pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 29 of 421 Generated by docbook2odf File Edit Select View Image Layer Tools Not only can a grid be helpful for judging distances and spatial relationships it can also permit you to align things e
355. r example we only defined one function text box which we registered e The location in the menu where the script will be inserted The exact location of the script is specified like a path in Unix with the root of the path being either toolbox or right click If your script does not operate on an existing image and thus creates a new image like our Text Box script will you ll want to insert it in the toolbox menu this is the menu in Gimp s main window where all the tools are located the selection tools magnifying glass etc If your script is intended to work on an image being edited you ll want to insert it in the menu that appears when you right click on an open image The rest of the path points to the menu lists menus and sub menus Thus we registered our Text Box script in the Text menu of the Script Fu menu of the Xtns menu of the toolbox Xtns Script Fu Text Text Box If you notice the Text sub menu in the Script Fu menu wasn t there when we began Gimp automatically creates any menus not already existing e A description of your script to be displayed in the Procedure Browser e Your name the author of the script e Copyright information e The date the script was made or the last revision of the script e The types of images the script works on This may be any of the following RGB RGBA GRAY GRAYA INDEXED INDEXEDA Or it may be none at all in our case we re creating an image and thus don t ne
356. r through Layer Stack Layer to Image Size Scale Layer The Scale Layer command resizes the layer and its contents The image loses some of its quality by being scaled The command displays a dialog where you can set parameters concerning the size of the layer and the image quality Activating the Command e You can access this command from the image menubar through Layer Scale Layer Description of the Scale Layer Dialog GNU Image Manipulation Program Page 280 of 421 Generated by docbook2odf xe O N E O O 2 S O xe a 2 xe o d 3 S o Layer Size Width eal fil Height 138 a pixels I 200 x 138 pixels 72 dpi Quality Interpolation Linear Crop Layer The Crop Layer command crops only the active layer to the boundary of the selection by removing any strips at the edge whose contents are all completely unselected Areas which are partially selected for example by feathering are not cropped If there is no selection for the image the menu entry is insensitive and grayed out Activating the Command e You can access this command from the image menubar through Layer Crop layer Example Autocrop Layer The Autocrop Layer command automatically crops the current layer by removing a border It looks for the the largest possible area around the outside edge which all has the same color and then crops this area from the layer You can use it to isolat
357. r which GIMP has good tools The purpose of this chapter is to give you an overview of those tools and the Situations in which they are useful You will not find detailed tutorials here in most cases it is easier to learn how to use the tools by experimenting with them than by reading about them Also each tool is described more thoroughly in the Help section devoted to it You will also not find anything in this chapter about the multitude of special effects that you can apply to an image using GIMP You should be familiar with basic GIMP concepts before reading this chapter but you certainly don t need to be an expert if you are you probably know most of this anyway And don t hesitate to experiment GIMP s powerful undo system allows you to recover from almost any mistake with a simple CtrlZ Most commonly the things that you want to do to clean up an imperfect photo are of four types improving the composition improving the colors improving the sharpness and removing artifacts or other undesirable elements of the image Improving Composition Rotating an Image It is easy when taking a picture to hold the camera not quite perfectly vertical resulting in a picture where things are tilted at an angle In GIMP the way to fix this is to use the Rotate tool Activate this by clicking its icon in the Toolbox or by pressing the R key capitalized while inside the image Make sure the Tool Options are visible and at the top make sur
358. ram it joins smoothing despeckle and sharpen enhancement functions It works on the whole image not on the selection This is something of a swiss army knife filter It has 3 distinct operating modes In all of the modes each pixel in the image is examined and processed according to it and its surrounding pixels values Rather than using the 9 pixels in a 3x3 block 7 hexagonal area Samples are taken the size of the hexagons being controlled by the radius parameter A radius value of 0 3333 means that the 7 hexagons exactly fit into the center pixel ie there will be no filtering effect A radius value of 1 0 means that the 7 hexagons exactly fit a 3x3 pixel array Options Operating Modes This filter can perform several distinct functions depending on the value of the parameter alpha Sharpen GNU Image Manipulation Program Page 330 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o sh rpr e S5 S Tie Ea ERT SA RENE Sas 1 0 Overview This filter is found in Image gt Filters Enhance Sharpen Most of digitized images need correction of sharpness This is due to digitizing process that must chop a color continuum up in points with slightly different colors elements thiner than sampling frequency will be averaged into an uniform color So sharp borders are rendered a little blurred The same phenomenon appears when printing color dots on paper The Sharpe
359. rated by docbook2odf This filter is found in Filters Light Effectsender Lighting Effects This filter simulates the effect you get produce any drop shadows and of cou Options Sparkle Parameter Settings when you light up a wall with a spot It doesn t rse doesn t reveal any new details in dark zones Flare Intensity Spike Length Spike Points Spike Angle 1 Random Spike Density Opacity Random Hue Random Saturation Preserve Luminosity Inverse Add Border Overview nr 1 00 es 10 00 eee 0 00 Pes 10 00 Natural Color Foreground Color Background Color You can find this filter in the image menu under Filters Light Effects Sparkle GNU Image Manipulation Program Generated by docbook2odf Page 345 of 421 o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o This filter adds sparkles to your image It uses the lightest points according to a threshold you have determined It is difficult to foresee where sparkles will appear But you can put white points on your image where you want sparkles to be Parameter Settings Sliders and input boxes allow you to set values SuperNova Parameter Settings Center of SuperNova A ES Y 128 l l Show Cursor coor MES Radius I nn 20 Spokes _ T 100 Random Hue C_I n o B Cancel Overview This filter is found in Filters Light Effectsender Super Nova This filter creates a big
360. rated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o amount of wind so a high value will render a storm You can also increase the effect by setting the Style to Blast which will produce thicker lines than Wind You can only set the wind in two directions either Left or Right However you can control which edge the wind will come from using the values Leading Trailing or Both Because Trailing will produce a black wind it creates a less convincing motion blur than Leading which will produce white wind The following illustrations are based on this image pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 359 of 421 Generated by docbook2odf Artistic filters Artistic filters introduction Artistic filters create artistic effects like cubism oil painting canvas Apply Canvas Overview This filter is found in Image gt Filters Artistic Apply Canvas This filter applies a canvas like effect to the current layer or selection It textures the image as if it were an artist s canvas Options o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 360 of 421 Generated by docbook2odf Parameter Settings Top Left C Bottom Left Bottom Right of Cancel Pox Cartoon Overview ELEL LETTY TTAN E a ae Sia i F Lo D e N xX
361. rectory for a scripts directory and add the scripts in this directory to the Script Fu database You Should place your personal scripts here GNU Image Manipulation Program Page 90 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o The Bare Essentials Every Script Fu script defines at least one function which is the script s main function This is where you do the work Every script must also register with the procedural database so you can access it within Gimp We ll define the main function first BERRRREE define script fu text boxinText inFont inFontsSizelinTextColor BERREE Here we ve defined a new function called script fu text box that takes four parameters which will later correspond to some text a font the font size and the text s color The function is currently empty and thus does nothing So far so good nothing new nothing fancy Naming Conventions Scheme s naming conventions seem to prefer lowercase letters with hyphens which I ve followed in the naming of the function However I ve departed from the convention with the parameters like more descriptive names for my parameters and variables and thus add the in prefix to the parameters so can quickly see that they re values passed into the script rather than created within it use the prefix the for variables defined within the script It s Gimp convention to name your s
362. representation of the active image Clicking on it brings up a dialog with a list of all the currently open images allowing you to make a different one active if you want to Clicking on the window where the image is displayed will accomplish the same thing though The Active Image preview is disabled by default If you want it you can enable it in the Toolbox Preferences tab At every start GIMP selects a tool the brush a color a brush and a pattern by default always the same If you want GIMP to select the last tool color brush and pattern you used when quitting your previous session check the Set input device settings on exit in Preferences Input Devices Image Window In GIMP each image that you have open is displayed in its own separate window In some cases multiple windows may all display the same image but this is unusual We will begin with a brief description of the components that are present by default in an GNU Image Manipulation Program Page 15 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o ordinary image window Some of these in fact can be made to disappear using commands in the View menu but you will probably find that you don t want to do that Title Bar At the top of the image window you will probably see a emphasis bar showing the name of the image and some basic information about it The emphasis bar is actually provided by the
363. ric Conical asymmetric Shapeburst angular Shapeburst spherical Shapeburst dimpled Spiral clockwise and Spiral counterclockwise these are described in detail below The Shapeburst options are the most interesting they cause the gradient to follow the shape of the selection boundary no matter how twisty it is Unlike the other shapes Shapeburst gradients are not affected by the length or direction of the line you draw for them as well as every other type of gradient you are required to click inside the selection and move the mouse but a Shapeburst appears the same no matter where you click or how you move Check out the Difference option in the Mode menu where doing the same thing even with full opacity will result in fantastic swirling patterns changing and adding every time you drag the cursor Activate Tool e The Blend Tool can be called in the following order from the image menu Tools Paint Tools Blend e The Tool can also be called by clicking the tool icon Key modifiers Defaults Options Painting Tools Pencil Paintbrush Airbrush GNU Image Manipulation Program Page 118 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o The tools in this group are GIMP s basic painting tools and they have enough features in common to be worth discussing together in this section Features common to all brush tools are described in the Common Features sec
364. rightness value ranging from O black to 255 white with intermediate values representing different levels of gray Essentially the difference between a grayscale image and an RGB Image is the number of color channels a grayscale image has one an RGB image has three An RGB image can be thought of as three superimposed grayscale images one colored red one green and one blue Actually both RGB and grayscale images have one additional color channel called the aloha channel representing opacity When the alpha value at a given location in a given layer is zero the layer is completely transparent and the color at that location is determined by what lies underneath When alpha is maximal the layer is opaque and the color is determined by the color of the layer Intermediate alpha values correspond to varying degrees of translucency the color at the location is a proportional mixture of color from the layer and color from underneath GNU Image Manipulation Program Page 22 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o In Gimp every color channel including the alpha channel has a range of possible values from O0 to 255 in computing terminology a depth of 8 bits Some digital cameras can produce image files with a depth of 16 bits per color channel Gimp cannot load such a file without losing resolution In most cases the effects are too subtle to be detected b
365. rks of the document must themselves be free in the same sense It complements the GNU General Public License which is a copyleft license designed for free software We have designed this License in order to use it for manuals for free software because free software needs free documentation a free program should come with manuals providing the same freedoms that the software does But this License is not limited to software manuals it can be used for any textual work regardless of subject matter or whether it is published as a printed book We recommend this License principally for works whose purpose is instruction or reference This License applies to any manual or other work in any medium that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License Such a notice grants a world wide royalty free license unlimited in duration to use that work under the conditions stated herein The Document below refers to any such manual or work Any member of the public is a licensee and is addressed as you You accept the license if you copy modify or distribute the work in a way requiring permission under copyright law A Modified Version of the Document means any work containing the Document or a portion of it either copied verbatim or with modifications and or translated into another language A Secondary Section is a named appendix or a front matter section of the Document that de
366. rough Layer Transparency Intersect with Selection e or from the pop up menu which appears when you right click on the active layer in the Layers Dialog Example Hi New layer o Background xe e N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 276 of 421 Generated by docbook2odf The Transform Submenu a Flip Horizontally 42 Flip Vertically 2 Rotate 90 degrees CW 43 Rotate 90 degrees CCW a Rotate 180 degrees Te Arbitrary Rotation Shiftt R Offset Shitt Ctrl O The Transform submenu of the Layer menu contains commands which flip or rotate the active layer of the image Activating the Submenu e You can access this submenu from the image menubar through Layer Transform The Contents of the Transform Submenu The Transform submenu contains the following commands Flip Horizontally The Flip Horizontally command reverses the active layer horizontally that is from left to right It leaves the dimensions of the layer and the pixel information unchanged Activating the Command e You can access this command from the image menubar through Layer Transform Flip Horizontally Example GNU Image Manipulation Program Page 277 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 3 S o Flip Vertically The Flip Vertically command reverses the active layer vertically that is from
367. rrying about it Because plugins are separate programs they communicate with the GIMP core ina special way The GIMP developers call it talking over a wire When a plugin crashes the communication breaks down and you will see an error message about a wire read error When a plugin crashes GIMP gives you a very ominous looking message telling you that the plugin may have left GIMP in a corrupted state and you should consider saving your images and exiting Strictly speaking this is quite correct because plugins have the power to alter almost anything in GIMP but for practical purposes experience has shown that corruption is actually quite rare and many users just continue working and don t worry about it Our advice is that you simply think about how much trouble it would cause you if something went wrong and weigh it against the odds Because of the way plugins communicate with GIMP they do not have any mechanism for being informed about changes you make to an image after the plugin has been started If you start a plugin and then alter the image using some other tool the plugin will often crash and when it doesn t will usually give a bogus result You should avoid running more than one plugin at a time on an image and avoid doing anything to the image until the plugin has finished working on it If you ignore this advice not only will you probably screw up the image you will probably screw up the undo system as well so that yo
368. s are absent in this function definition when compared to other programming languages e First notice that the parameters don t have any types that is we didn t declare them as strings or integers etc Scheme Is a type less language This is handy and allows for quicker script writing e Second notice that we don t need to worry about how to return the result of our function the last statement is the value returned when calling this function Type the function into the console then try something like BERR RRRRRRRR AdCXYE AdcCXYMSHO E4 TTT Lists Lists And More Lists We ve trained you in variables and functions and now enter the murky swamps of Scheme s lists GNU Image Manipulation Program Page 86 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Defining A List Before we talk more about lists it is necessary that you know the difference between atomic values and lists You ve already seen atomic values when we initialized variables in the previous lesson An atomic value Is a single value So for example we can assign the variable x the single value of 8 in the following statement BRRRRRRE lct 8 xs amp Ex BREE We added the expression x at the end to print out the value assigned to x normally you won t need to do this Notice how let operates just like a function The value of the last statement is the value returned A
369. s are tileable but tileable patterns are nicest for many purposes A texture by the way is the same thing as a pattern In GIMP there are three main uses for patterns e With the Bucket Fill tool you can choose to fill a region with a pattern instead of a solid color e With the Clone tool you can paint using a pattern with a wide variety of paintbrush shapes e When you stroke a path or selection you can do it with a pattern instead of a solid color You can also use the Clone tool as your choice if you stroke the selection using a painting tool Note Patterns do not need to be opaque If you fill or paint using a pattern with translucent or transparent areas then the previous contents of the area will show through from behind it This is one of many ways of doing overlays in GIMP When you install GIMP it comes presupplied with a few dozen patterns which seem to have been chosen more or less randomly You can also add new patterns either ones you create yourself or ones you download from the vast number available online GIMP s current pattern used in most pattern related operations is shown in the Brush Pattern Gradient area of the Toolbox Clicking on the pattern symbol brings up the Patterns dialog which allows you to select a different pattern You can also access the Patterns dialog by menu or dock it so that it is present continuously To add a new pattern to the collection so that it shows up in the Pattern
370. s dialog you need to save it in a format GIMP can use in a folder included in GIMP s pattern search path There are several file formats you can use for patterns To make a pattern available you place it in one of the folders in GIMP s pattern search path By default the pattern search path includes two folders the system patterns GNU Image Manipulation Program Page 36 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o folder which you should not use or alter and the patterns folder inside your personal GIMP directory You can add new folders to the pattern search path using the Pattern Folders page of the Preferences dialog Any PAT file or in GIMP 2 2 any of the other acceptable formats included in a folder in the pattern search path will show up in the Patterns dialog the next time you start GIMP There are countless ways of creating interesting patterns in GIMP using the wide variety of available tools and filters particularly the rendering filters You can find tutorials for this in many locations including the Gimp home page Some of the filters have options that allow you to make their results tileable Also the Tileable Blur filter allows you to blend the edges of an image in order to make it more smoothly tileable Also of interest are a set of pattern generating scripts that come with GIMP you can find them in the Toolbox menu under Xtns Script Fu Patter
371. s is a very useful filter if you want to create intricate patterns It s perfect for making psychedelic batik like textures or for imitating patterns in stained glass as in a church window It seems clear that the plugin works by simulating the physics of light striking a grating Unfortunately the original authors never got around to writing down the theory behind it or explaining what the parameters mean The best approach then is just to twiddle things and see what happens Fortunately almost anything you do seems to produce interesting results CML Explorer Overview tan i r l i Lt Sr i ao GNU Image Manipulation Program Page 389 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o l ea This filter is the king of texture creating filters It is extremely efficient but very complex lt uses a mathematical method named Cellular Automata Starting filter You can find this filter from the image menu through Filters Render Pattern CML Explorer Options Grid Parameter Settings Horizontal Vertical Intersection width hfi E fo E px EI ga Spacing j16 fje Bl p px E ga ores He Ab H mE a E ee ga Overview This filter is found in Filters Render Pattern Grid It renders a Cartesian grid in the active layer on top of the existing contents The width Spacing o
372. s screen is only to make the user aware of the GIMP personal settings directory subdirectories and files creation process before it begins You just have to have a look and click to proceed GNU Image Manipulation Program Page 10 of 421 Generated by docbook2odf t a o N x e e 2 8 o 3 gt 2 v o ww hn o c o v PS home marco gimp 2 2 For a proper GIMP installation a folder named Y home marco gimp 2 2 needs to be created E gimpre This folder will contain a number of important files Lj gtkre Click on one of the files or folders in the tree to get 7 pluginre more information about the selected item 1 menure al sessionre templaterc unitre brushes fonts gt aradients 3 This window shows you the files that GIMP will create It will have some complaints if you told it to install some place that it don t have permission to be There is a scroll bar to see all the things GIMP has created for you Creating folder fhome marco gimp 2 2 Y Copying file fhome marco gimp 2 2 gtkre from fete gimp 2 0 gtkre Y Creating folder home marco gimp 2 2 brushes Y Creating folder fhome marco gimp 2 2 fonts Y Creating folder home marco gimp 2 2 gradients Y Creating folder home marco gimp 2 2 palettes Y Creating folder home marco gimp 2 2 patterns Y Creating folder home marco gimp 2 2 plug ins Y Creating folder home marc
373. s top varies according to borders In most cases threshold is under top and border is thick The Laplacian edge detection uses the second derivative fig 3 The top of the curve is now at zero and clearly identified That s why Laplace filter renders a thin border only a pixel wide But this derivative gives several zeros corresponding to small ripples resulting in false edges Some blurring before applying edge filters is often necessary it flattens small ripples in signal and so prevents false edges Difference of Gaussians o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o GNU Image Manipulation Program Page 325 of 421 Generated by docbook2odf Vilber ee Constuction Fit a m Preview Smoothing parameters Radius 1 a 0 a Radius 2 2 0 amp E m Normalize m Invert ine x on Fa Overview This filter is located at Filters Edge detect Difference of Gaussians This filter is new in GIMP 2 2 It does edge detection using the so called Difference of Gaussians algorithm which works by performing two different Gaussian blurs on the image with a different blurring radius for each and subtracting them to yield the result This algorithm is very widely used in artificial vision maybe in biological vision as well and is pretty fast because there are very efficient methods for doing Gaussian blurs The most important parameters are the blurring radii for the two G
374. se button with the pointer positioned over the font example Aa a window showing a larger text example will pop up Pack my box with five dozen liquor jugs pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 176 of 421 Generated by docbook2odf Image management related dialogs Buffers dialog zs birds 228 x 469 p birds 1 374 x 790 Buffers are temporary repositories for image data created when you cut or copy part of a drawable a layer layer mask etc You can save a document in this buffer in two ways Edit Buffer Copy Named or Edit Buffer Cut Named A dialog pops up asking you to name a buffer to store the data in There is no hard limit on the number of named buffers you can create although of course each one consumes a share of memory The Buffers dialog shows you the contents of all existing named buffers and allows you to operate on them in several ways It also shows you at the top the contents of the Global Buffer but this is merely a display you can t do anything with it The Buffers dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in several ways e From the Toolbox menu File Dialogs Buffer e From an image menu Dialogs Buffer or Edit Buffer Paste Named e From the Tab menu in any dockable dialog Add Tab Buffer Named buffers are not saved across sessions The onl
375. ses a procedural brush but it is the only one available in GIMP A more extensive implementation of procedural brushes Is a goal of future development for GIMP In addition to the brush pixmap each GIMP brush has one other important property the brush Spacing This represents the distance between consecutive brush marks when a continuous brushstroke is painted Each brush has an assigned default value for this which can be modified using the Brushes dialog Gradients GNU Image Manipulation Program Page 34 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o A gradient is a set of colors arranged in a linear order The most basic use of gradients is by the Blend tool sometimes known as the gradient tool or gradient fill tool it works by filling the selection with colors from a gradient You have many options to choose from for controlling the way the gradient colors are arranged within the selection There are also other important ways to use gradients including When you install GIMP it comes presupplied with a large number of interesting gradients and you can add new ones that you create or download from other sources You can access the full set of available gradients using the Gradients dialog a dockable dialog that you can either activate when you need it or keep around as a tab in a dock The current gradient used in most gradient related operations is shown
376. sh Tools Overview for a description of tool options that apply to many or all brush tools pe O N E O O 2 S O xe a 2 xe o 4 G d 0 S o GNU Image Manipulation Program Page 130 of 421 Generated by docbook2odf Transform Tools Common Features Zf Crop amp Resize XS Rotate Shift R Pa Scale Shift T Eq Shear Shift S 5 Perspective Shift P Flip Shift F Inside the Transformation tool dialog you will find seven tools to modify the presentation of the image or the presentation of an element of the image selection layer or path Each transform tool has an Option dialog and an Information dialog to set parameters Move Tool The Move Tool is used to move layers selections or guides It works also on texts Activate Tool e The Move Tool can be called tn the following order from the image menu Tools Transform Tools Move e The Tool can also be called by clicking the tool icon or by the M keyboard shortcut e The Move tool is automatically activated when you create a guide Holding down the space bar changes the active tool to Move temporarily The Move tool remains active as long as the space bar is held down The original tool is reactivated after releasing the space bar Default behaviour By default this tool works on the active layer and the Select a Layer or a Guide option is GNU Image Manipulation Program Page 131 of 421 Generated by docbook2odf pe O N E O O
377. some things you can do that may cause a preview to be incorrect If you suspect that this may be happening you can force a new preview to be generated by holding down the Ctrl key and clicking in the Preview area One thing that strikes many people when they first see the File Open dialog is that there is no way to enter the name of the file using the keyboard Actually this can be done but the feature is a bit hidden if you type CtriL with the dialog focused an Open Location dialog pops up with a space to type the file name This dialog is described in more detail below In the great majority of cases if you select a file name from the list and click the Open button in the lower right corner or the dialog GIMP will automatically determine the file type for you On rare occasions mainly if the file type is unusual and the name lacks a meaningful extension this may fail If this happens you can tell GIMP specifically what type of file it is by expanding the Select File Typ option at the bottom of the dialog and choosing an entry from the list that appears More commonly though if GIMP fails to open an image file it is either corrupt or not in a Supported format e Open Location If instead of a file name you have a URI i e a web address for the image you can open it using the menu by choosing File Open Location from either the Toolbox menu or an image menu This brings up a small dialog that allows you to enter or paste
378. source These caveats apply as much to the Plugin Registry as to any other source of plugins The Registry is available to any plugin creator who wants to use it there is no systematic oversight Obviously if the maintainers became aware that something evil was there they would remove it That hasn t happened yet There is however for GIMP and its plugins the same warranty as for any other free software namely none Plugins have been a feature of GIMP for many versions However plugins written for one version of GIMP can hardly ever be used successfully with other versions They need to be ported sometimes this is easy sometimes not Many plugins are already available in several versions Bottom line before trying to Install a plugin make sure that it is written for your version of GIMP Using Plugins For the most part you can use a plugin like any other GIMP tool without needing to be aware that it is a plugin But there are a few things about plugins that are useful to understand GNU Image Manipulation Program Page 45 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 3 S o One is that plugins are generally not as robust as the GIMP core When GIMP crashes it is considered a very serious thing it can cost the user a lot of trouble and headache When a plugin crashes the consequences are usually not so serious In most cases you can just continuing working without wo
379. splay Filters The images you create we hope will be seen by many people on many different systems The image which looks so wonderful on your screen may look somewhat different to people with sight deficiencies or on a screen with different settings from yours Some information might not even be visible Display Filters allow you to view your image as if it were seen by people with a sight deficiency or on a different screen Don t worry the filters display the image in a different way but they never change the image Besides that if you save the image that is displayed the original image Is saved For the same reason you can t undo the action of a filter with CtrlZ The filters available are called Color Deficient Vision Gamma Contrast and Color Proof Activating the Command e You can access this command from the image menubar through View Display Filters Description of the Display Filters Dialog 4 Configure Color Display Filters 2zinnias png l Available Filters Color Deficient Vision Gamma Contrast Color Proof Configure selected filter GNU Image Manipulation Program Page 240 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o This dialog has two small windows The left window displays the Available Filters You can move a filter to the right window by selecting it and clicking on the right arrow button The Active Filters window on
380. ssively from left to right and from top to bottom all the pixels of the kernel action area It multiplied the value of each of them by the kernel corresponding value and added results 100 0 50 1 50 0 100 0 100 0 100 0 100 0 100 0 100 0 100 0 50 The initial pixel took the value 50 Previously when the initial pixel had value 50 it took the value 100 of the above pixel the filter doesn t work on the image but on a copy and so disappeared into the 100 background pixels As a graphical result the initial pixel moved a pixel downwards Options Examples Design of kernels is based on high levels mathematics You can find ready made kernels on the Web Here are a few examples o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 334 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 335 of 421 Generated by docbook2odf Dilate Overview This filter is found in Filters Generic Dilate This filter widens and enhances dark areas of the active layer or selection For every image pixel it brings the pixel Value luminosity into line with the lowest Value the darkest of the 8 neighbouring pixels 3x3 matrix So a dark pixel is added around dark areas An isolated pixel on a brighter background will be changed to a big pixel composed of 9 pixels
381. st of the documentation Everything here is explained in much greater depth elsewhere With a few exceptions we have avoided cluttering this section with a lot of links and cross references everything mentioned here is so high level that you should easily be able to locate it in the index pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 21 of 421 Generated by docbook2odf Working with Images Image types It is tempting to think of an image as something that corresponds with a single display window or to a single file such as a JPEG file but really a Gimp image is a rather complicated structure containing a stack of layers plus several other types of objects a selection mask a set of channels a set of paths an undo history etc In this section we are going to take a detailed look at all of the components of an image and the things you can do with them The most basic property of an image Is its mode There are three possible modes RGB grayscale and indexed RGB stands for Red Green Blue and indicates that each point tn the image Is represented by a rea level a green level and a blue level Because every humanly distinguishable color can be represented as a combination of red green and blue RGB images are full color Each color channel has 256 possible intensity levels More details in Color Models In a grayscale image each point is represented by a b
382. st people find the Path tool to be more useful than the Scissors because even though it does not have the intelligent edge finding capability the paths it produces persist until you delete them and can be altered at any time How to Activate he Intelligent Scissors can be activated from an image menu as Tools Selection Tools Intelligent Scissors from the Toolbox by clicking on the tool icon or from the keyboard using the shortcut i Key modifiers Defaults The Scissor tool does not have any special key modifiers only the ones that affect all selection tools in the same way See Selection Tools for help with these Options Scissors LEa Z Antialiasing Feather edges Radius 10 0 Show interactive boundary See Selection Tools for help with options that are common to all these tools Only options that are specific to the Intelligent Scissors tool are explained here GNU Image Manipulation Program Page 114 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Brush Tools Common Features g Pencil op Paintbrush Eraser a Airbrush iF Ink A Clone Convolve J Smudge Dodge Burn ci The GIMP Toolbox includes nine brush tools all grouped together at the bottom in the default arrangement The feature they all have in common is that all of them are used by moving the pointer across the image display creating brushstrok
383. supplied with GIMP are stored in a system gradients folder By default gradients that you create are stored in a folder called gradients in your personal GIMP directory Any gradient files ending with the extension ggr found in one of these folders will automatically be loaded when you start GIMP You can add more directories to the gradient search path if you want to in the Gradients tab of the Data Folders pages of the Preferences dialog GNU Image Manipulation Program Page 35 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o New in GIMP 2 2 is the ability to load gradient files in SVG format used by many vector graphics programs To make GIMP load an SVG gradient file all you need to do is place it in the gradients folder of your personal GIMP directory or any other folder in your gradient search path You can find a large number of interesting SVG gradients on the web in particular at OpenClipArt Gradients You won t be able to see what these gradients look like unless your browser supports SVG but that won t prevent you from downloading them Patterns A pattern is an image usually small used for filling regions by tiling that is by placing copies of the pattern side by side like ceramic tiles A pattern is said to be tileable if copies of it can be adjoined left edge to right edge and top edge to bottom edge without creating obvious seams Not all useful pattern
384. t as well as the rest of the list but how do we access the second third or other elements of a list There exist several convenience functions to access for example the head of the head of the tail of a list caadr the tail of the tail of a list cddr etc The basic naming convention is easy The a s and d s represent the heads and tails of lists SO BERBER Carli cdrll carlix ff amp BREE GNU Image Manipulation Program Page 89 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o could be written as BERRRRRE cadarlix Ti TTT To view a full list of the list functions refer to the Appendix which lists the available functions for the version of Scheme used by Script Fu To get some practice with list accessing functions try typing in the following except all on one line if you re using the console use different variations of car and cdr to access the different elements of the list BERRRREE lL et e Dee XB LO S465 oC SVS 9810 6 See TTT TTT BERBER Bol aceiyourlicar cdrilicodefihere BERREEEE EEEEHE Try accessing the number 3 in the list using only two function calls If you can do that you re on your way to becoming a Script Fu Master In Scheme a semicolon marks a comment It and anything that follows it on the same line are ignored by the script interpreter so you can use this to add comments to jog your memory when
385. t CMYK or YUV color models The right image is decomposed in three color channels red green and blue and the Alpha channel for transparency On the right image the transparency is displayed as a gray checkerboard In the color channel white is always white because all the colors are present and black is black The red hat is visible in the red channel but quite invisible in the other channels This is the same for plain green and blue which are visible only in their own channels and invisible in others Calling the Dialog The Channel dialog can be activated in many ways e from the toolbox menu File Dialogs Channels e from the image menu Dialogs Channels e from another dialog menu Add Tab Channels Using the Channeldialog Overview The top channels are the color channels and the optional Alpha channel They are always organized in the same order and they cannot be erased Selection masks are described below and displayed as a list in the dialog Every channel appears in the list in form of a thumbnail A right click in a channel thumbnail opens the channel menu Channel attributes fp Every channel is shown in the list with its own attributes The main attribute is the name of the channel itself You can edit selection masks by double clicking on their name A double click on the thumbnail opens a full dialog where you can also set the visual aspect of the channel in the image window In front of the thumbnail there is an eye ico
386. t the rendered image later with Image Colors The other three parameters affect the rendering process and don t show in the preview window Sample Density which controls the resolution of the rendered pattern is the most important of these The Camera parameters allow you to zoom and offset the flame pattern until you re happy with what you see in the preview window Flame also offers the possibility to store and load your favorite patterns Options IFS Compose GNU Image Manipulation Program Page 385 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o IfsCompose ake at Rotate Scale stretch Render Options Preview W Auto ine oe Undo ge Redo Select All Recompute Center Transformation 1 Spatial Transformation Color Transformation X 0 39 Scale 0 55 Asymmetry 1 00 Y 0 25 Angle 23 87 Shear 0 00 l Flip Relative Probability 1 00 Reset gt Open al Save Cancel aP ok Overview This filter is found in Filters Render Nature IFS fractal This fractal based plug in is truly wonderful With this versatile instrument you can create amazingly naturalistic organic shapes like leaves flowers branches or even whole trees IFS stands for Iterated Function System The key to using this plug in lies in making very small and precise movements in fractal Space The outcome is always hard to predict and you have to
387. tal mode is not set there is a canvas buffer that is composited with the active layer he two images above were created using a brush with spacing set to sixty he image on the left shows non incremental painting and the image on the right shows the difference that incremental painting can produce Incremental paint mode results in each brush application through the duration of a stroke being rendered in addition to any previous brush renderings When you enlarge an image pixels become apart if image resolution is not enough These missing pixels are replaced by pixels that are calculated from surrounding pixels by interpolation Interpolation methods in The GIMP are labelled with a speed marker Faster methods lead to lower quality transformations whereas slower methods lead to higher quality transformations This format supports compression and works at all color depths The image compression is adjustable but beware Too high a compression could severely reduce image quality since JPEG compression is lossy Use JPEG to create TrueColor Web graphics or if you don t want your image to take up a lot of space JPEG is a good format for photographs JPEG files usually have an extension jpg JPG or jpeg It is a very widely used format because it compresses images very efficiently while minimizing the loss of image quality No other format comes close to achieving the same level of compression It does not however support transparency
388. tations Here are some quick examples illustrating the differences between prefix infix and postfix notations We ll add a 1 and 3 together e Prefix notation 1 3 the way Scheme will want it e Infix notation 1 3 the way we normally write it e Postfix notation 1 3 the way many HP calculators will want it Practicing In Scheme Now let s practice what we have just learned Start up Gimp if you have not already done so and choose Xtns Script Fu Console This will start up the Script Fu Console window which allows us to work interactively in Scheme In a matter of moments the Script Fu Console will appear The Script Fu Console Window At the bottom of this window is an entry field entitled Current Command Here we can test out simple Scheme commands interactively Let s start out easy and add some numbers GNU Image Manipulation Program Page 83 of 421 Generated by docbook2odf xe O N E O O 2 S O xe a 2 xe o d 3 S o BERRRREE 8 SHS BREE Typing this in and hitting Enter yields the expected answer of 8 in the center window Now what if we wanted to add more than one number The function can take two or more arguments so this is not a problem BERBER B SH5EC LETT TT This also yields the expected answer of 14 So far SO good we type in a Scheme statement and it s executed immediately in the Script Fu Console window Now for a word of caution Wa
389. tch Out For Extra Parens If you re like me you re used to being able to use extra parentheses whenever you want to like when you re typing a complex mathematical equation and you want to separate the parts by parentheses to make it clearer when you read it In Scheme you have to be careful and not insert these extra parentheses incorrectly For example say we wanted to add 3 to the result of adding 5 and 6 together BERR RRRR SRS SE o a BREE Knowing that the operator can take a list of numbers to add you might be tempted to convert the above to the following BERR RRER S SO 7 BREE However this is incorrect remember every statement in Scheme starts and ends with parens so the Scheme interpreter will think that you re trying to call a function named 5 in the second group of parens rather than summing those numbers before adding them to 3 The correct way to write the above statement would be BR RRRRRR S MSHoO E7 BREE Make Sure You Have The Proper Spacing Too If you are familiar with other programming languages like C C Perl or Java you know that you don t need white space around mathematical operators to properly form an expression BRR RBRES 5 838 5 83 85 BREE These are all accepted by C C Perl and Java compilers However the same is not true for Scheme You must have a space after a mathematical operator or any other function name or operator in Scheme for it to be correctl
390. ted as a separate input device and each input device has its own separate tool assignment the reverse end will then continue to function as an Eraser as long as you don t select a different tool with it How to Activate he Eraser can be activated from an image menu as Tools Paint Tools Eraser from he Toolbox by clicking on the tool icon or from the keyboard using the shortcut E Key modifiers See the Brush Tools Overview for a description of key modifiers that have the same effect on all brush tools e Ctrl For the Eraser holding down the Ctrl key puts it into color picker mode so that it selects the color of any pixel it is clicked on Unlike other brush tools however the Eraser sets the background color rather than the foreground color This is more useful because on drawables that don t support transparency erasing replaces the erased areas with the current background color e Alt For the Eraser holding down the Alt key switches it into anti erase mode as described below in the Tool Options section Note that on some systems the Alt key is trapped by the Window Manager If this happens to you you may be able to use Shift Alt instead Tool Options See the Brush Tools Overview for a description of tool options that apply to many or all GNU Image Manipulation Program Page 122 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o brush tools Opacit
391. ted by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o though so you should not use it unless you really need the selectivity The Pixelize filter produces the well known Abraham Lincoln effect by turning the image into a set of large square pixels The Oilify filter in the Artistic Filters group has a similar effect but with irregular blobs instead of perfectly square pixels You can find a nice explanation of the Abraham Lincoln effect at The Motion Blur filter blurs in a specific direction at each point which allows you to create a sense of motion either linear radial or rotational Finally the Tileable Blur filter is really the same thing as a Gaussian blur except that it wraps around the edges of an image to help you reduce edge effects when you create a pattern by tiling multiple copies of the image side by side Tileable Blur is actually implemented by a Script Fu script that invokes the Gaussian blur plug in Blur Overview bss f N i tata nL Te st ee ee en e GNU Image Manipulation Program Page 289 of 421 Generated by docbook2odf o l 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o The simple Blur filter produces an effect similar to that of an out of focus camera shot To produce this blur effect the filter takes the average of the present pixel value and the value of adjacent pixels and sets the pres
392. ted by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o If you want to draw straight lines with the Pencil or any of several other paint tools click at the starting point then hold down Shift and click at the ending point Activate Tool e The Pencil Tool can be called in the following order from the image menu Tools Paint Tools Pencil e The Tool can also be called by clicking the tool icon e or by clicking on the N keyboard shortcut Key modifiers Defaults Options Opacity 1 1000 E Mode Normal E Brush z Pressure sensitivity jv Opacity Size Color Fade out fv Incremental A Use color from gradient Gradient Gg _ Reverse Length 100 px E Repeat Triangular wave M See the Brush Tools Overview for a description of tool options that apply to many or all brush tools Paintbrush Tool pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 120 of 421 Generated by docbook2odf brush Activate Tool e You can call the Paintbrush Tool in the following order from the image menu Tools Paint Tools Paintbrush e The Tool can also be called by clicking the tool icon e or by using the P keyboard shortcut Key modifiers Defaults Options Paintbrush Mode Normal z Pressure sensitivity Opaciy Hardness Size T Color Fade out Length 100 px
393. tes a random black and white maze pattern The result completely overwrites the previous contents of the active layer A typical example is shown below Can you find the route from the center to the edge Options Jigsaw Number of Tiles Overview You can find this filter in Filters Render Pattern Jigsaw o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o GNU Image Manipulation Program Page 392 of 421 Generated by docbook2odf This filter will turn your image into a jigsaw puzzle The edges are not anti aliased so a little bit of smoothing often makes them look better i e Gaussian blur with radius 1 0 If you want to be able to easily select individual puzzle piece areas as for the example above render the jigsaw pattern on a separate layer filled with solid white and set the layer mode to Multiply You can then select puzzle pieces using the magic wand fuzzy select tool on the new jigsaw layer Options Qbist Overview You can find this filter from the image menu through Filters Render Pattern Qbist The Qbist filter generates random textures A starting texture is displayed in the middle square and different variations surround it If you like one of the alternative textures click on it The chosen texture now turns up in the middle and variations on that specific theme are displayed around it When you have found the texture you want click on it and then click OK The texture wi
394. the URI a Enter location URI http wee gimp org images wilberright jpeg e Open Recent lf the image is one that you previously created using GIMP perhaps the easiest way to open it is from the menu using File Open Recent This gives you a scrollable list of the images you have most recently worked on in with icons beside them You need only select the one you want and it will be opened e File Browser If you have associated the file type of the image with GIMP either when you installed GIMP or later then you can navigate to the file using a file manager Such as Nautilus in Linux or Windows Explorer in Windows and once you have found it double click on the icon If things are set up properly this will cause the image to open in GIMP e Drag and Drop xe O N E O O 2 S O xe a 2 xe o 4 d 0 S o GNU Image Manipulation Program Page 52 of 421 Generated by docbook2odf Alternatively once you have found the file you can click on its icon and drag it into the GIMP Toolbox If instead you drag it into an existing GIMP image it will be added to that image as a new layer or set of layers For many applications you can click on a displayed image a full image not just a thumbnail and drag it into the GIMP toolbox e Copy and Paste For some applications if the application gives you a way of copying the image to the clipboard you can then open the image in GIMP by choosing Fil
395. the collection provided that you follow the rules of this License for verbatim copying of each of the documents in allother respects GNU Image Manipulation Program Page 419 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 hn 0 S o You may extract a single document from such a collection and distribute it individually under this License provided you insert a copy of this License into the extracted document and follow this License in all other respects regarding verbatim copying of that document A compilation of the Document or its derivatives with other separate and independent documents or works in or on a volume of a storage or distribution medium is called an aggregate if the copyright resulting from the compilation is not used to limit the legal rights of the compilation s users beyond what the individualworks permit When the Document is included in an aggregate this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document If the Cover Text requirement of section 3 is applicable to these copies of the Document then if the Document is less than one half of the entire aggregate the Document s Cover Texts may be placed on covers that bracket the Document within the aggregate or the electronic equivalent of covers if the Document is in electronic form Otherwise they must appear on printed covers that bracket the who
396. the keyboard shortcut Ctrl F Re show Last The Re show Last command interactively runs the most recently executed plug in Unlike the Repeat Last command which does not display a dialog the Re show Last command displays a dialog window if the plug in has one It is displayed with the settings you used the last time you ran the plug in assuming that the plug in follows the GIMP programming conventions Please note that this command repeats the most recently executed plug in regardless of whether it is in the Filters menu or not When you are using a plug in especially one that does not have a preview window you may very well have to adjust the parameters several times before you are satisfied with the results To do this most efficiently you should memorize the shortcuts for Undo and Re show Last Ctrl Z followed by Ctrl Shift F Activating the Command e You can access this command from the image menubar through Filters Re show filter r e or by using the keyboard shortcut Ctrl Shift F Reset All Filters Normally each time you run an interactive plug in its dialog is displayed with all of the settings initialized to the ones you used the last time you ran it This may be a problem if you made a mistake setting the values and you can t remember what they were originally One way to recover is to exit GIMP and start again but the Reset all Filters command is a Slightly less drastic solution it resets the values for all p
397. the right displays filters you have chosen and which will be applied if the adjacent box is checked You can move filters from the right window to the left window by using the left arrow button If you select a filter by clicking on its name its options are displayed below the two windows in the Configure Selected Filter area Color Deficient Vision Description of the Color Deficient Vision dialog In this drop down menu you can select from among Gamma The Gamma dialog The correspondence between electrical intensity and color brightness is not exact and it depends upon the device the camera the scanner the monitor etc Gamma is a coefficient used to correct this correspondence Your image must be visible in both dark and bright areas even if it is displayed on a monitor with too much luminence or not enough The Gamma Display Filter allows you to get an idea of the appearance of your image under these conditions Contrast The Contrast dialog Here we are back in the medical domain Contrast Sensitivity is the capacity of the visual system to distinguish slight differences in contrast Some people with cataracts which means that the lens has opaque crystals that scatter light over the retina or retinal disease for instance due to diabetes which destroys the rods and cones have a deficiency in sensitivity to contrast for example they would have difficulties distinguishing spots on a dress With the Contrast Filte
398. the system brushes folder which you Should not use or alter and the brushes folder inside your personal GIMP directory You can add new folders to the brush search path using the Brush Folders page of the Preferences dialog Any GBR GIH or VBR file included in a folder in the brush search path will show up in the Brushes dialog the next time you start GIMP or as soon as you press the Refresh button tn the Brushes dialog TI i When you create a new parametric brush using the Brush Editor it is automatically saved in your personal brushes folder There are a number of web sites with downloadable collections of GIMP brushes Rather than supplying a list of links that will soon be out of date the best advice is to do a search with your favorite search engine for Gimp brushes There are also many collections of brushes for other programs with painting functionality Some can be converted easily into GIMP brushes some require special conversion utilities and some cannot be converted at all Most fancy procedural brush types fall into the last category If you need to know look around on the web and if you don t find anything look for an expert to ask GNU Image Manipulation Program Page 77 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Chapter Using GIMP as an Expert pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulat
399. then it happened Common LISP messily dumped core when it could not allocate the 17 MB it needed to generate a parser for a simple grammar using yacc An unbelieving moment passed there was one shared look of disgust and then our project was vapor We had to write something ANYTHING useful Something in C Something that did not rely on nested lists to represent a bitmap Thus the GIMP was born Like the phoenix glorious new life sprung out of the burnt remnants of LISP and yacc Ideas went flying decisions were made the GIMP began to take form An image manipulation program was the consensus A program that would at the very least lessen the necessity of using commercial software under Windoze or on the Macintoy A program that would provide the features missing from the other X painting and imaging tools A program that would help maintain the long tradition of excellent and free UNIX applications Six months later we ve reached an early beta stage We want to release now to start working on compatibility issues and cross platform stability Also we feel now that the program Is actually usable and would like to see other interested programmers developing plug ins and various file format support GNU Image Manipulation Program Page 410 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o The early days of GIMP pe O N E O O 2 S O xe a 2 xe o
400. ting there are good instructions and examples and the main library that plugins use to interface with GIMP called ibgimp has a well documented API Good programmers learning by modifying existing plugins are often able to accomplish interesting things after just a couple of days of work GNU Image Manipulation Program Page 47 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Using Script Fu Scripts Script Fu is what the Windows world would call macros But Script Fu is more powerful than that Script Fu is based on an interpreting language called Scheme and works by using querying functions to the Gimp database You can do all kinds of things with Script Fu but an ordinary Gimp user will probably use it for automating things that e You want to do frequently e Are really complicated to do and hard to remember Remember that you can do a whole lot with Script Fu The scripts that come with Gimp can be quite useful but they can also serve as models for learning Script Fu or at least as a framework and source of modification when you make your own script Read the Script Fu Tutorial in the next section if you want to learn more about how to make scripts We will describe some of the most useful scripts in this chapter but we won t cover them all There are simply too many scripts Some of the scripts are also very simple and you will probably not need any documentat
401. tings Random Seed zo l Randomize Randomization na 50 Repeat DO fo l Cancel Overview This filter is found in Filters Noise Hurl The Hurl filter changes each affected pixel to a random color so it produces real random noise All color channels including an alpha channel if it is present are randomized All possible values are assigned with the same probability The original values are not taken into account All or only some pixels in an active layer or selection are affected the percentage of affected pixels is determined by the Randomization option Options Scatter RGB Parameter Settings pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 321 of 421 Generated by docbook2odf Overview This filter is found in the image window menu under Filters Noise Scatter RGB The Scatter RGB filter adds a normally distributed noise to a layer or a selection It uses the RGB color model to produce the noise noise is added to red green and blue values of each pixel A normal distribution means that only slight noise is added to the most pixels in the affected area while less pixels are affected by more extreme values If you apply this filter to an image filled with a solid grey color and then look at its histogram you will see a classic bell shaped Gaussian curve The result is very naturally looking noise Options Pick
402. tion Features specific to an individual tool are described in the section devoted to that tool The Pencil is the crudest of the tools in this group tt makes hard non anti aliased brushstrokes The Paintbrush is intermediate it is probably the most commonly used of the group The Airbrush is the most flexible and controllable it is the only one for which the amount of paint applied depends on the speed of brush movement This flexibility also makes it a bit more difficult to use than the Paintbrush however All of these tools share the same brushes and the same options for choosing colors either from the basic palette or from a gradient All are capable of painting in a wide variety of modes Key modifiers Options Pencil The Pencil tool is used to draw free hand lines with a hard edge The pencil and paintbrush are similar tools The main difference between the two tools is that although both use the same type of brush the pencil tool will not produce fuzzy edges even with a very fuzzy brush It does not even do anti aliasing Why would you want to work with such a crude tool Perhaps the most important usage is when working with very small images such as icons where you operate at a high zoom level and need to get every pixel exactly right With the pencil tool you can be confident that every pixel within the brush outline will be changed in exactly the way you expect GNU Image Manipulation Program Page 119 of 421 Genera
403. tion GF Add to Selection TF Selection to Path ff Stroke Path Copy Path a Paste Path gt Import Path Lal Export Path The Paths menu can be brought up by right clicking on a path entry in the list in the Paths dialog or by choosing the top entry Paths Menu from the Paths dialog Tab menu This menu gives you access to most of the operations that affect paths Colormap dialog Indexed Palette Color index 12 Hex triplet eze028 ee eee The Colormap Indexed Palette is a better name dialog allows you to edit the colormap of an indexed image If the mode of the active image is RGB or Grayscale instead of Indexed the dialog is empty and unusable This is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in two ways Dialog call e From the Toolbox menu File Dialogs Colormap GNU Image Manipulation Program Page 162 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o G d 3 S o e From the image menu Dialogs Colormap Colormaps and Indexed Images In an Indexed image colors are assigned to pixels by an indirect method using a lookup table called a colormap In GIMP the maximum number of entries in a colormap is 256 For a maximum sized colormap each index from 0 to 255 is assigned an arbitrary RGB color There are no rules restricting the colors that can be assigned to an index or the order they
404. tion at Colonze The Tools dialog is used mainly to control the appearance of the Toolbox It allows you to customize the set of tools for which icons are shown in the Toolbox and the order in which the icons are arranged Probably the most common use for it is to make the Color tools available directly from the Toolbox You can also use the Tools dialog to select a tool by clicking on its symbol but for this purpose you might as well just use the Toolbox The Tools dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in several ways e From the Toolbox menu File Dialogs Tools e From an image menu Dialogs Tools e From the Tab menu in any dockable dialog Add Tab Tools Grid List modes In the Tab menu you can choose between View as Grid and View as List In Grid mode the tools are laid out in a rectangular array In List mode they are lined up vertically with each row showing the tool name tool icon and an eye icon if the tool is currently visible in the Toolbox Using the Tools dialog The most basic thing you can do is to select a tool by clicking on its icon this has the same effect as clicking on an icon in the Toolbox You can do this in either List or Grid mode the other functions of the dialog are available only in List mode The most important function of the Tools dialog is to let you choose which tools to make visible in the Toolbox by toggling t
405. tion for Selection Coloring Type for Selection Flip Selection my Replicate Selection Split Segments at Midpoints Split Segments Uniformly m Delete Selection Re center Midpoints in Selection Re distibute Handles in Selection Blend Endpoints Colors Blend Endpoints Opacity You can access the Gradient Editor menu either by right clicking on the gradient display or by choosing the top item in the dialog s tab menu The menu allows you to set the left and right edge colors for each segment and control the transition from one color to the other The following commands can be found in the menu There is no undo available within the Gradient Editor so be careful Palettes GNU Image Manipulation Program Page 172 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o PE Dark pastels 256 Default 23 m ga 240 BE Firecode 256 Go 256 I crayblue 256 PA c rays 32 BE c ray violet 256 E creens 256 A palette is a set of discrete colors in no particular order See the Palettes section for basic information on palettes and how they can be created and used The Palettes dialog is used to select a palette by clicking on it in a list or grid view A few dozen more or less randomly chosen palettes are supplied with GIMP and you can easily add new palettes of your own The Palettes dialog also give you access to several opera
406. tions for creating new palettes or manipulating the ones that already exist The Palettes dialog is not the same thing as the Index Palette dialog which is used to manipulate the colormaps of indexed images Activate Dialog The Palettes dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in several ways e From the Toolbox menu File Dialogs Palettes e From an image menu Dialogs Palettes e From the Tab menu in any dockable dialog Add Tab Palettes Using the Palettes dialog Clicking on a palette in the dialog makes it GIMP s active palette This does not really have any significance though Double clicking on a palette brings up the Palette Editor which allows you to set GIMP s foreground or background colors by clicking on colors in the palette display Double clicking on a palette name in List View mode lets you to edit the name Note that you are only allowed to change the names of palettes that you have added yourself not those that are supplied with GIMP If you edit a name that you are not allowed to change it will revert back to its previous value as soon as you hit return or move the pointer focus elsewhere Palettes Menu GNU Image Manipulation Program Page 173 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o Ei Edit Palette J New Palette LES Import Palette
407. title GNU Image Manipulation Program subtitle User Manual revhistory copyright legalnotice Permission is granted to copy distribute and or modify this document under the terms of the GNU Free Documentation License Version 1 2 or any later version published by the Free Software Foundation with no Invariant Sections no Front Cover Texts and no Back Cover Texts A copy of the license is included in the section enophrased GNU Free Documentation License pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 1 of 421 Generated by docbook2odf GIMP User Manual Authors and Contributors pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 2 of 421 Generated by docbook2odf Chapter Introduction pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 3 of 421 Generated by docbook2odf Welcome to The GIMP The GIMP is a multiplatform photo manipulation tool GIMP is an acronym for GNU Image Manipulation Program The GIMP is suitable for a variety of image manipulation tasks including photo retouching image composition and image construction lt has many capabilities It can be used as a simple paint program an expert quality photo retouching program an online batch processing system a mass production image renderer an image format converter
408. tmage menubar through View Show Guides e or by using the keyboard shortcut Shift Ctrl T Snap to Guides The Snap to Guides command enables and disables snap to guides When snap to guides is enabled the guides you set see Show Guides almost seems magnetic when you move a layer or selection the guides appear to pull on it when it approaches This is enormously useful for accurate placement of image elements Activating the Command e You can access this command from the tmage menubar through View Snap to Guides Show Grid By using the Show Grid command you can enable and disable displaying the grid When you enable it the grid overlays the image and makes it easier for you to line up selected image elements You can set the default for the grid in the Image Window Appearance dialog See also the Configure Grid command and the Snap to Grid command Activating the Command e You can access this command from the image menubar through View Show Grid Snap to Grid The Snap to Grid command enables and disables snap to grid When snap to grid is enabled the grid you set see Show Grid almost seems magnetic when you move a layer or selection the grid points appear to pull on it when it approaches This is enormously useful for accurate placement of image elements Activating the Command e You can access this command from the image menubar through View Snap to Grid Padding Color From Theme E Light Check Color I Dark
409. to do it for you which in the case of a computer serving multiple users at the same time can be a good idea that way the administrator and other users do not get mad at you for abusing the machine nor do you get a badly underperfoming GIMP If it is your machine and only serves a single user at a given time this could mean money or drinks as price for the service e Start changing the value a bit each time and check that it goes faster and faster with each increase but the system does not complain about lack of memory Be forewarned that sometimes lack of memory shows up suddenly with some applications being killed to make space for the others e Do some simple math and calculate a viable value Maybe you will have to tune it later but maybe you have to tune it anyway with the other previous methods At least you know what is happening and can get the best from your computer Let s suppose you prefer the last option and want to get a good value to start with First you need to get some data about your computer This data is the amount of RAM installed in your system the operating system s swap space available and a general idea about the speed of the disks that store the operating system s swap and the directory used for GIMP s swap You do not need to do disk tests nor check the RPM of the disks the thing is to see which one seems clearly faster or slower or whether all are similar You can change GIMP s swap directory in the Folders pa
410. to tell whether you have adjusted colors adequately A good objective technique is to find a point in the image that you know should be either white or a shade of gray Activate the Color Picker tool the eyedropper symbol in the Toolbox and click on the aforesaid point this brings up the Color Picker dialog If the colors are correctly adjusted then the red green and blue components of the reported color should all be equal if not then you should see what sort of adjustment you need to make This technique when well used allows even color blind people to color correct an image If your image is washed out which can easily happen when you take pictures in bright light try the Hue Saturation tool which gives you three sliders to manipulate for Hue Lightness and Saturation Raising the saturation will probably make the image look better In same cases it is useful to adjust the lightness at the same time Lightness GNU Image Manipulation Program Page 70 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o here is similar to Brightness in the Brightness Contrast tool except that they are formed from different combinations of the red green and blue channels The Hue Saturation tool gives you the option of adjusting restricted subranges of colors using the buttons at the top of the dialog but if you want to get natural looking colors in most cases you Should avoid
411. top to bottom It leaves the dimensions of the layer and the pixel information unchanged Activating the Command e You can access this command from the image menubar through Layer Transform Flip Vertically Rotate 90 degrees CW The Rotate 90 degrees CW command rotates the active layer by 90 around the center of the layer with no loss of pixel data The shape of the layer is not altered but the rotation may cause the layer to extend beyond the bounds of the image This is allowed in GIMP and it does not mean that the layer is cropped However you will not be able to see the parts which extend beyond the boundary of the image unless you resize the image canvas or move the layer Activating the Command e You can access this command from the image menubar through Layer Transform Rotate 90 degrees CW Rotate 90 degrees CCW The Rotate 90 degrees CCW command rotates the active layer by 90 counter clockwise around the center of the layer with no loss of pixel data The shape of the layer is not altered but the rotation may cause the layer to extend beyond the bounds of the image This is allowed in GIMP and it does not mean that the layer is cropped However you will not be able to see the parts which extend beyond the boundary of the image unless you resize the image canvas or move the layer Activating the Command e You can access this command from the image menubar through Layer Transform Rotate 90 degrees CCW Rotate 180 d
412. trength of the light per area and the chrominance or proportion of color chroma where the chrominance again consists of two components The development of the YUV color model also goes back to the development of color television PAL where ways were sought for transmitting the color information in addition to the black and white signal in order to achieve backwards compatibility with old black and white televisions without having to maintain the available transmission bandwidth From the YUV color model of the analog television techiques the YCrCb color model was developed which is used for most kinds of digital image and video compression Erroneously the YUV color model is also often spoken about in those areas although the YCbCr model is actually used This often causes confusion For the calculation of the luma signals also Leuchtdichte signal the underlying RGB data Is first verrechnet with the gamma value of the output device and an R G B signal is obtained The three individual components are added together with different weights to form the brightness information which also functions as the BAS signal for the old black and white televisions Y R G B The exact calculation is more complicated however since some aspects of the color perception of the human eye have to be taken into account For example green is perceived to be lighter than red and this is perceived to be lighter than blue Furthermore gamma correction
413. u won t even be able to recover from your foolishness Installing New Plugins The plugins that are distributed with GIMP don t require any special installation Plugins that you download yourself do There are several scenarios depending on what OS you are using and how the plugin is structured In Linux it is usually pretty easy to install a new plugin in Windows it is either easy or very hard In any case the two are best considered separately Linux Most plugins fall into two categories small ones whose source code Is distributed as a single c file and larger ones whose source code Is distributed as a directory containing multiple files including a Makefile For a simple one file plugin call it borker c installing it is just a matter of running the command gimptool 2 0 install borker c This command compiles the plugin and installs it in your personal plugin directory gimp 2 2 plugins unless you have changed it This will cause it to be loaded automatically the next time you start GIMP You don t need to be root to do these things in fact you shouldn t be If the plugin fails to compile well be creative Once you Nave installed the plugin how do you activate it The menu path is determined by the plugin itself so to answer this you need to either look at the documentation for the plugin if there is any or launch the Plugin Description dialog from Xtns Plugins Details search the plug in by its name and look ot the Tr
414. u cannot modify this list The lower part lists your bookmarks you can add or remove bookmarks To add a bookmark select a directory or a file in the middle panel and click on the Add button at the bottom of the left panel You can also use the Add to bookmarks command in the context menu which you get by clicking the right mouse button You can delete a bookmark by selecting it and clicking on the Remove button The middle panel displays a list of the files in the current directory Change your current directory by double left clicking on a directory in this panel Select a file with a single left click You can then open the file you have selected by clicking on the Open button Note that a double left click opens the file directly if you have selected a file different from the current one a message warns you before GIMP overwrites your work Right clicking on the middle panel displays the Open Location dialog that allows you to type a path to a file You can also open this dialog by typing CtrlIL The selected image Is displayed tn the Preview window if it is an image created by GIMP File size resolution and the image s composition are displayed below the preview window If your image has been modified by another program click on the Preview window to update it The path of the current directory is displayed above the middle panel You can navigate along this path by clicking on one of the buttons This button shows All Files by defa
415. u don t use the Select All command only the opaque island that you clicked on will be filled Activate Tool e The Bucket Fill can be called in the following order from the image menu Tools Paint Tools Bucket Fill e The Tool can also be called by clicking the tool icon Key modifiers Defaults Options Gradient Tool GNU Image Manipulation Program Page 117 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o _ met io TA o T as at 7 oes E a ERASER E i This tool fills the selected area with a gradient blend of the foreground and background colors by default but there are many options To make a blend drag the cursor in the direction you want the gradient to go and release the mouse button when you feel you have the right position and size of your blend The softness of the blend depends on how far you drag the cursor The shorter the drag distance the sharper it will be There are an astonishing number of things you can do with this tool and the possibilities may seem a bit overwhelming at first The two most important options you have are the Gradient and the Shape Clicking the Gradient button in the tool options brings up a Gradient Select window allowing you to choose from among a variety of gradients supplied with GIMP you can also construct and save custom gradients For Shape there are 11 options Linear Bilinear Radial Square Conical symmet
416. ual is installed on your system You can find the most recent help at http docs gimp org en index html Activating the Command e You can access this command from the toolbox menubar through Help Help e or by using the keyboard shortcut F1 Context Help The Context Help command makes the mouse pointer context sensitive and changes its Shape to a You can then click on a window dialog or menu entry and GIMP displays help about it if it is available You can alSo access context help at any time by pressing the F1 key while the mouse pointer is over the object you would like help about Activating the Command e You can access this command from the toolbox menu through Help Context Help e or by using the keyboard shortcut Shift F1 Tip of the Day The Tip of the Day command displays the Tip of the Day dialog This dialog contains useful tips to help you gain a better understanding of some of the subtle points of using The GIMP New users will find it very valuable to pay attention to these because they often suggest ways of doing something that are much easier or more efficient than more obvious approaches GNU Image Manipulation Program Page 213 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww hn o c o Description of the dialog window the stack You may add transparency to it by right clicking in The layer named Background is special because it lacks transparency
417. ulation Program Page 179 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Options The scroll bar allows you to browse all images you have opened before The Open the selected entry button allows you to open the image you have selected With Shift key pressed it raises an image hidden behind others With Ctrl key pressed it opens the Open Image dialog The Remove the selected entry button allows you to remove an image from the History dialog The image Is removed from the recently open images list also But the image itself is not deleted The Recreate Preview button updates preview in case of change With Shift key pressed it acts on all previews With Ctrl key pressed previews that can t be found out are deleted Templates Dialog Image Templates Templates are templates for an image format to be created Gimp offers you a lot of templates and you can create your owns When you create a New image you can access to the list of existing templates but you can t manage them The Templates dialog allows you to manage all these templates The Templates dialog is a dockable dialog see the section on Dialogs and Docking for help on manipulating it It can be activated in two ways e From the Toolbox menu File Dialogs Templates e From an image menu Dialogs Templates In the Tab menu for the Templates dialog you can choose between View as Grid and View
418. ult This means that all file types will be displayed in the middle panel even if they are not images You can fi ter the list for a particular file type The Determine File Type button has a default of Automatic In most cases you don t need to pay any attention to this because the GIMP can determine the file type automatically In a few rare situations neither the file extension nor internal information in the file are enough to tell GIMP the file type If this happens you can set it by selecting it from the list Open Location The Open Location dialog lets you load an image from a network location specified by a URI in any of the formats that GIMP supports or from a path to your hard disk or any drive The default directory name is home lt username gt on Linux and C Documents and Settings lt username gt My Documents My Images on Windows which is used as the base of the relative address You can also enter an absolute path When you are visiting an Internet site you can right click on an image and choose Copy link address in the drop down menu Then paste it in the Open Location dialog to open it in GIMP GNU Image Manipulation Program Page 216 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o d 3 S o Activating the Command e You can access this command from the Toolbox menu and the image menu File Open Location Description of the dialog window 2 Enter l
419. unit you have currently selected in the Unit Editor dialog You can then edit the values to create your new unit Plug In Browser The Plug In Browser command displays a dialog window which shows all of the extensions plug ins which are currently loaded in GIMP both as a list and as a hierarchical tree structure Since many of the filters are actually plug ins you will certainly see many familiar names here Please note that you do not run the extensions from this dialog window Use the appropriate menu entry to do that instead For example you can run filter plug ins by using the Filter command on the image menubar Activating the Command e You can access this command from the toolbox menubar through Xtns Plug in Browser Description of the Plug In Browser dialog window GNU Image Manipulation Program Page 210 of 421 Generated by docbook2odf o_ 3 o N x e o 2 8 o 3 gt 2 a o ww in o c o 296 Plugin Interaces Ls View Tree views script_ftu_3d outline loge Temoorary Procedure lt Toolrox xtns se pt Fus _ocos s30 Cutline 30 Uutlinc 30 Outline 30 Truchet Creates outlinen texts with drop shaclover Parameters run mace INTZA Inteose vc non nteractwe Add Bevel F Pattern STRING Pattern Add Rarder string STRING Teal Adjust FG BG value FLOAT Fonts 72 p xels Alier Glow tent STRING ont Yaluc FLOAT Outline slur radius AAN W Value FLOAT Shacow sl
420. ur radius Alia Maz 2 valuz FLOAT Burrpriaz aphialayer blur radius toggle INT32 Default aumpmap settings value FLOAT Shacow ofset search Lep C coe The figure above shows the list view of the Plug In Browser You can click on the name of a plug in in the scrolled window to display more information about it Select the List View by clicking on the tab at the top of the dialog You can search for a plug in by name by entering part or all of the name in the Search text box and clicking on the Search by Name button The left part of the dialog then displays the matches found The figure above shows the tree view of the Plug In Browser You can click on the name of a plug in in the scrolled window to display more information about it You can click on the arrowheads to expand or contract parts of the tree Select the Tree View by clicking on the tab at the top of the dialog You can search for a plug in by name by entering part or all of the name in the Search text box and clicking on the Search by Name button The left part of the dialog then displays the matches found Not everything in these huge dialog windows is visible at the same time Use the scroll bars to view their content The Procedure Browser The Procedure Browser command displays the procedures in the PDB the Procedure Database These procedures are functions which are called by the scripts or plug ins You can find a more detailed description of the PDB
421. ut affecting the unselected areas Each tool has its own individual properties but the selection tools also share a number of options and features in common These common features are described here the variations are explained in the following sections for each tool specifically If you need help with what a selection is in GIMP and how it works see Selection There are six selection tools e Rectangle Select e Ellipse Select e Free Select the Lasso e Select Contiguous Regions the Magic Wand e Select by Color e Select Shapes from Image Intelligent Scissors In some ways the Path tool can also be thought of as a selection tool any closed path can be converted into a selection It also can do a great deal more though and does not share the same set of options with the other selection tools Key modifiers Defaults The behavior of selection tools is modified tf you hold down the Ctrl Shift and or Alt keys while you use them Advanced users find the modifier keys very valuable but novice users often find them confusing Fortunately it is possible for most purposes to use the Mode buttons described below instead of modifier keys Options Here we describe the tool options that apply to all selection tools options that apply only to some tools or that affect each tool differently are described in the sections devoted to the individual tools The current settings for these options can be seen in the Tool Options dialog
422. ve any Warranty Disclaimers If the Modified Version includes new front matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document you may at your option designate some or all of these sections as invariant To do this add their titles to the list of Invariant Sections in the Modified Version s license notice These titles must be distinct from any other section titles You may add a section Entitled Endorsements provided it contains nothing but endorsements of your Modified Version by various parties for example statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard You may add a passage of up to five words as a Front Cover Text and a passage of up to 25 words as a Back Cover Text to the end of the list of Cover Texts in the Modified Version Only one passage of Front Cover Text and one of Back Cover Text may be added by or through arrangements made by any one entity If the Document already includes a cover text for the same cover previously added by you or by arrangement made by the Same entity you are acting on behalf of you may not add another but you may replace the old one on explicit permission from the previous publisher that added the old one The author s and publisher s of the Document do not by this License give permission to use their names for publicity for orto assert or imply endorsement of a
423. ve any special key modifiers only the ones that affect all selection tools in the same way See Selection Tools for help with these Options oie QE S 7 Antialiasing Feather edges The Free Select tool has no special tool options only the ones that affect all selection tools in the same way See Selection Tools for help with these pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o GNU Image Manipulation Program Page 110 of 421 Generated by docbook2odf Fuzzy Selection Tool Magic Wand File Xtns Help meer FT RPA FS fs amp BB T Ansar The Fuzzy Select Magic Wand tool is designed to select areas of the current layer or image based on color similarity It starts selecting when you click at a spot in the image and expands outward like water flooding low lying areas selecting contiguous pixels whose colors are similar to the starting pixel You can control the threshold of similarity by dragging the mouse downward or to the right the farther you drag it the larger the selected region And you can reduce the selection by dragging upwards or to the left When using this tool it is very important to pick the right starting point If you select the wrong spot you might get something very different from what you want or even the opposite The Wand is a good tool for selecting objects with sharp edges It is fun to use so beginners often start out using it a lot You will proba
424. ves them ina clipboard so that they can later be pasted using the Paste Paste Into or Paste As New commands If there is no selection the entire current layer is cut The areas whose contents are cut are left transparent if the layer has an alpha channel or filled with the layer s background color otherwise The Cut command only works on the current active layer Any layers above or below the active layer are ignored Activating the Command e You can access this command from the image menubar through Edit Cut e or by using the keyboard shortcut Ctrl X Copy The Copy command makes a copy of the current selection and stores it in the Clipboard The information can be recalled using the Paste Paste Into or Paste As New commands If there is no selection the entire current layer is copied Copy only works on the current active layer Any layers above or below it are ignored Activating the Command GNU Image Manipulation Program Page 223 of 421 Generated by docbook2odf xe O N E O O 2 S O xe a 2 xe o d 3 S o e You can access this command from the image memubar through Edit Copy e or by using the keyboard shortcut Ctrl C Copy Visible The Copy Visible command is similar to the Copy command However it does not just copy the contents of the current layer it copies the contents of the visible layers or the selection of the visible layers that is the ones that are marked wit
425. w Dork i i l E Tool options Shift Ctri T FF Quit ri Q a Device Status Rect Select Layers Ctrl i Channets Mode i Gh OG 2 Paths Ed Colormap H Histogram W Selection Editor T Auto shrink selection 4 Navigation Sh Undo History Feather edges Shitt Ctri 6 Shift Ctrl P Cti 6 cr P a ag Brae gt Document History J Templates c Tools i Error Copsole The Dialogs submenu of the Toolbox s File menu contains a list of available dialogs that you can use while you are editing an image patterns palettes brushes etc You can open and close dialogs as needed or if you want them to stay around you can dock them Dialogs are described in detail in Accessing the Dialogs Submenu e You can access this submenu in the Toolbox through File Dialogs pe O N E O O 2 S O xe a 2 xe o G d 3 S o GNU Image Manipulation Program Page 207 of 421 Generated by docbook2odf Xtns Introduction to the Xtns menu fH Plug In Browser Procedure Browser A Unit Editor Epson Status Monitor Script Fu The Xtns menu gets its somewhat cryptic name from the term Extensions Accordingly you will find various commands for managing extensions also Known as plug ins and for accessing scripts here Besides the commands presented here you might find other entries on this menu They are not part of GIMP itself but are extensions to it You can
426. which you should always have visible when you are using tools Most users keep it docked directly below the Toolbox To make the interface consistent the same options are presented for all selection tools even though some of them don t have any effect for some of the tools Additional information When moving a selection beyond the boundaries of the image canvas the selection will be cropped to the image area Selections can exist on the visible canvas only Selection movements and changes are however kept in the undo buffer should you need to repair an error Rectangle Selection Tool GNU Image Manipulation Program Page 106 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o 4 d 0 S o The Rectangle Selection tool is designed to select rectangular regions of an image it is the most basic of the selection tools but very commonly used For information on selections and how they are used in GIMP see Selections for information on features common to all selection tools see Selection Tools This tool is also used for rendering a rectangle on an image To render a filled rectangle create a rectangular selection and then fill it using the Bucket Fill tool To create a rectangular outline the simplest and most flexible approach is to create a rectangular selection and then stroke it If you want to round the edges of a rectangular selection the easiest method is using Select Rounde
427. window zooming Enlarging an image zooming in is useful if you need to work with high precision making pixel level image modifications or precise selections On the other hand reducing an image zooming out is handy for getting an overall impression of the image and seeing the results of changes which affect the entire image Please note that zooming is not undoable since it does not affect the image data only the way it is displayed Besides the entries in this submenu there is also a zoom pull down menu at the bottom edge of the image window if the status bar is displayed You can also make settings regarding zooming in the Navigation dialog You can also use the Magnify tool which lets you zoom a particular area of the image Activating the Submenu e You can access this command from the image menubar through View Zoom Note that the Zoom label on the View menu shows the current zoom factor for example Zoom 100 Contents of the Zoom submenu The various Zoom submenu commands are described below along with their default GNU Image Manipulation Program Page 238 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o keyboard shortcuts if any When you are working at the pixel level you can use the New view command This allows you to see what Is happening to the image at its normal size at the same time Shrink Wrap The Shrink Wrap command resizes the
428. window so that it is exactly the same size as the Image at the current zoom factor If the image doesn t completely fit on the screen the image window is enlarged so that the largest possible part of the image is shown Please note that GIMP will do this automatically if you set the Resize window on zoom and Resize window on image size change options in the Image Window page of the Preferences dialog Please note also that the behavior described here is not performed by GIMP itself but by the window manager a part of the operating system of your computer For that reason the functionality described may be different on your computer or in the worst case might not be available at all Activating the Command e You can access this command from the image menubar through View Shrink Wrap e or by using the keyboard shortcut Ctrl E Full Screen The Fullscreen command enables and disables displaying the image window on the entire screen When it is enabled the image window takes up the whole screen but the image stays the same size When you enable full screen mode the menubar may not be displayed but if this happens you can right click on the image to access the image menu You can set the default appearance for full screen mode in the Preferences menu If you use GIMP on an Apple Macintosh computer full screen mode may not work since Apple doesn t provide the necessary functionality Instead you can maximize the image window by cl
429. windowing system not by GIMP itself so its appearance may vary with different operating systems window managers and or themes In the Preferences dialog you can customize the information that appears here if you want to Image Menu Directly below the emphasis bar appears the Image Menu unless it has been suppressed This menu gives you access to nearly every operation you can perform on an image There are some global actions that can only be accessed via the Toolbox menu You can also get the Image Menu by right clicking Inside the image or by left clicking on the little arrow symbol in the upper left corner if for some reason you find one of these more convenient More most menu operations can also be activated from the keyboard using Alt plus an accelerator key underlined in the menu emphasis More you can define your own custom shortcuts for menu actions if you enable Use Dynamic Keyboard Shortcuts in the Preferences dialog Menu Button Clicking on this little button gives you the Image Menu except in a column instead of a row Mnemonics users who don t want the menu bar visible can acces to this menu by pressing the Shift F10 key Ruler In the default layout rulers are shown above and to the left of the image indicating coordinates within the image You can control what type of coordinates are shown if you want to By default pixels are used but you can change to other units using the Units setting described below
430. wn Paste Into clips the pasted image data by the existing selection The new selection can be moved as usual but it is always clipped by the original selection area If no selection exists the Paste Into command places the data from the Clipboard into the center of the canvas as the Paste command does Activating the Command e You can access this command from the image menubar through Edit Paste Into Paste as New The Paste As New command creates a new image and pastes the image data from the Clipboard into it If the data is not rectangular or square in shape any regions that do not extend to the edge of the canvas are left transparent an Alpha channel is automatically created Of course you have to Copy your selection before you use this command so GNU Image Manipulation Program Page 224 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o that you get an image with the same dimensions as the selection Activating the Command e You can access this command from the image menubar through Edit Paste as New Buffers YO CutNamed Shift Ctrl x Copy Named Shift Ctrl C Paste Named Shift Ctrl V The commands in this submenu operate on named buffers You can use the Buffers dialog to view and manage any named buffers you have created Activating the Submenu e You can access this submenu from the image menubar through Edit Buffer Cut Named
431. works by using two different colors that you can define in the Colors tab These two colors then create wave patterns based on a sine function You can set the X and Y scales which determine how stretched or packed the texture will be You can also set the Complexity of the function a high value creates more interference or repetition in the pattern An example is shown below Options Fractal Explorer Overview Lo ke e N xX e e 2 o e ke gt 2 3 0 Ww hn o GNU Image Manipulation Program Page 396 of 421 Generated by docbook2odf Starting filter This filter is found in Filters Render Nature Fractal Explorer Options Parameters Colors Fractals Fractal Parameters xmn 2 00000 G XMAX gt 2 00000 G MIN 150000 ymax j 150000 E TER 0 50 00000 E Q Zoom Gut cy ee ee 0 20000 Undo S Open Reset lal Save x Realtime Preview Redraw Zoom Redo Fractal Type x Mandelbrot Barnsley Man o war Julia O Barnsley 3 Lambda gt D Barnsley1 Spider 0 Sierpinski x pe a 2 a pe Gfig o Overview tT GNU Image Manipulation Program Page 397 of 421 Generated by docbook2odf This filter is a tool You can create geometrical figures to add them to the image It Is very complex hope this paper will help you When using this filter elements inserted in the image will b
432. xactly with the grid if you toggle View Snap to Grid in the Image menu this causes the pointer to warp perfectly to any grid line located within a certain distance You can customize the snap distance threshold by setting Snap distance in the Tool Options page of the Preferences dialog but most people seem to be happy with the default value of 8 pixels Note that it is perfectly possible to snap to the grid even if the grid is not visible It isn t easy to imagine why you might want to do this though Guides File Edit Select View Image Layer Tools Sieh ate fa OAE eee li m dF Bi BW Cancel CL rr ee ort In addition to the image grid GIMP also gives you a more flexible type of positioning aid guides These are horizontal or vertical lines that you create by clicking on one of the rulers and dragging into the image You can create as many guides as you like positioned whereever you like To move a guide after you have created it activate the Move tool in the Toolbox or press the M key you can then click and drag a guide To delete a guide simply drag it outside the image Holding down the Shift key you can move everything but a guide using the guides as an effective alignment aid As with the grid you can cause the pointer to snap to nearby guides by toggling View Snap to Guides in the image menu If you have a number of guides and they are making it difficult for you to judge the image properly you can hide them
433. xe a 2 xe o G d 3 S o Toggle QuickMask It has the same action as clicking on the small button in the bottom left corner of the image See Quick Mask Activate Dialog e This command is found at Select Toggle QuickMask e Default shortcut is ShiftQ Save to Channel The Select to Channel command saves the selection as a channel The channel can then be used as a channel selection mask You can find more information about them in the Channel Dialog section Activating the Command e You can access this command from the image menubar through Select Save to Channel e You can also access it from the Selection Editor To Path The To Path command converts a selection into a path The image does not seem to change but you can see the new path in the Paths Dialog By using the Path tool in the Toolbox you can precisely adapt the outline of the selection You can find further information regarding paths in the Paths dialog section Activating the Command e You can access this command from the image menubar through Select To Path e You can also access it from the Selection Editor which offers you a lot of Advanced Options pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 236 of 421 Generated by docbook2odf View Introduction to the View Menu L New View Dot for Dot Zoom 100 Shrink Wrap Ctr E Fullscreen F11 y Info Window Sh
434. y M 1000 Mode Normal Brush Pressure sensitivity m Opacity Size Fade out Length px Incremental Hard edge Antierase lt Alt gt See the Brush Tools Overview for a description of tool options that apply to many or all brush tools The Eraser tool has only one special option Anti Erase but the Opacity control is mentioned here as well because its name may be a bit confusing Airbrush Tool Activate Tool e The Airbrush Tool can be called from the image menu Tools Paint Tools Airbrush e The Tool can also be called by clicking the tool icon Key modifiers Defaults Options pe O N E O O 2 S O xe a 2 xe o d 3 S o GNU Image Manipulation Program Page 123 of 421 Generated by docbook2odf Airbrush Mode Normal Brush z Pressure sensitivity Hardness Rate Size Color Fade out Length 100 px Z Incremental Use color from gradient Gradient G Reverse Length 100 px l Repeat Triangular wave See the Brush Tools Overview for a description of tool options that apply to many or all brush tools Ink Tool The Ink tool uses a simulation of an ink pen with a controllable nib to paint solid brush strokes with an antialiased edge The size shape and angle of the nib can be set to determine how the strokes will be rendered Activate Tool e You can call the Ink Tool in the following
435. y the human eye but in some cases mainly where there are large areas with slowly varying color gradients the difference may be perceptible The third type indexed images Is a bit more complicated to understand In an indexed image only a limited set of discrete colors are used usually 256 or less These colors form the colormap of the image and each point in the image is assigned a color from the colormap Indexed images have the advantage that they can be represented inside a computer in a way that consumes relatively little memory and back in the dark ages say ten years ago they were very commonly used As time goes on they are used less and less but they are still important enough to be worth supporting in Gimp Also there are a few important kinds of image manipulation that are easier to implement with indexed images than with continuous color RGB images Some very commonly used types of files including GIF and PNG produce indexed images when they are opened in Gimp Many of Gimp s tools don t work very well on indexed images and many filters don t work at all because of the limited number of colors available Because of this it is usually best to convert an image to RGB mode before working on it If necessary you can convert it back to indexed mode when you are ready to save it Gimp makes it easy to convert from one image type to another using the Mode command in the Image menu Some types of conversions of course
436. y Is insensitive and grayed out See the Layer Masks section for more information Activating the Command e You can access this command from the image menubar through Layer Mask Apply Layer Mask e or from the pop up menu you get by right clicking on the active layer in the Layers Dialog Delete Layer Mask The Delete Layer Mask command deletes the active layer s layer mask without modifying the active layer itself If the active layer does not have a layer mask the menu entry Is insensitive and grayed out Activating the Command e You can access this command from the image menubar through Layer Mask Delete Layer Mask e or from the pop up menu you get by right clicking on the active layer in the Layers Dialog Edit Layer Mask When you click on the Edit Layer Mask item on the Layer Mask submenu a check is displayed next to it the layer mask becomes the active component of the current layer and the layer mask is displayed in the Layers Dialog with a white border When you uncheck it the layer itself becomes the active component and it is displayed with a white border You can also activate the component you want more simply by clicking on it in the Layers Dialog Activating the Command e You can access this command from the image menubar through Layer Mask Edit Layer Mask e You can undo this action by unchecking the menu entry in the LayerMask menu or by clicking on the layer component in the Layers Dialog Disabl
437. y interpreted by the Scheme interpreter Practice a bit with simple mathematical equations in the Script Fu Console until you re totally comfortable with these initial concepts GNU Image Manipulation Program Page 84 of 421 Generated by docbook2odf pe O N E O O 2 S O xe a 2 xe o hn S o Variables And Functions Now that we know that every Scheme statement is enclosed in parentheses and that the function name operator is listed first we need to know how to create and use variables and how to create and use functions We ll start with the variables Declaring Variables Although there are a couple of different methods for declaring variables the preferred method is to use the let construct If you re familiar with other programming languages this construct is equivalent to defining a list of local variables and a scope in which they re active As an example to declare two variables a and b initialized to 1 and 2 respectively you d write BERRRREEE lL cc ae See ae See LEG 29 TT TTT LTT TT TTT TT Halb BRR RRREEE BREE or aS one line BERR RRRR let i 8 alll O82 0 8 Hallb ff PTT TTT You ll have to put all of this on one line if you re using the console window In general however you ll want to adopt a similar practice of indentation to help make your scripts more readable We ll talk a bit more about this in the section on White Space This dec
438. y points that should be corners aren t found the curve goes wild around that point e Filter Percent To produce the new point use the old point plus this times the neighbors e Filter Secondary Surround Number of adjacent points to consider if Filter Surround points defines a straight line e Filter Surround Number of adjacent points to consider when filtering e Keep Knees This check box says whether or not to remove knee points after finding the outline e Line Reversion Threshold If a spline is closer to a straight line than this value it remains a Straight line even if it would otherwise be changed back to a curve This is weighted by the square of the curve length to make shorter curves more likely to be reverted e Line Threshold How many pixels on the average a spline can diverge from the line determined by its endpoints before it is changed to a straight line e Reparametrize Improvement If reparameterization doesn t improve the fit by this much percent the algorithm stops doing it e Reparametrize Threshold Amount of error at which it is pointless to reparameterize This happens for example when the algorithm is trying to fit the outline of the outside of an O with a single spline The initial fit is not good enough for the Newton Raphson iteration to improve it It may be that it would be better to detect the cases where the algorithm didn t find any corners e Subdivide Search Percentage of the curve
439. y slider to get the wanted opacity Then anchor the selection outside the selection the mouse pointer comes with an anchor icon When you click the floating selection disappears from the Layer Dialog and the selection is at the right place and partially transparent anchoring works this way only if a selection tool is activated you can also use the command in the context menu that you get by right clicking on the selected layer in the layer dialog And if you use this function frequently CtriC to copy the selection CtrlV to paste it creating so a floating selection adapt the opacity then make Layer New Layer that pastes the floating selection into the new layer You can also create a shortcut for the New Layer command to use keys only e Another way Layer Mask Layer mask to add a layer mask to the layer with the selection initializing it with the selection Then use a brush with the wanted opacity to paint the selection with black i e paint it with transparency Then Layer Mask Apply Layer Mask See Undoing Almost anything you do to an image in GIMP can be undone You can undo the most recent action by choosing Edit Undo from the image menu but this is done so frequently that you really should memorize the keyboard shortcut Ctrl Z Undoing can itself be undone After having undone an action you can redo it by choosing Edit Redo from the image menu or use the keyboard shortcut Ctrl Y It is often helpful to judge the effect
440. y way to save their contents Is to paste them into images Buffers Global Buffer 281 x 254 a birds2 228 x 469 g pa Se Blaja In the Tab menu for the Buffers dialog you can choose between View as Grid and View as List In Grid mode the buffers are laid out in a rectangular array In List mode they are lined up vertically with each row showing a preview of the contents of the buffer its GNU Image Manipulation Program Page 177 of 421 Generated by docbook2odf xe e N E O O 2 S O xe a 2 xe o d 3 S o name and its pixel dimensions S Paste Buffer H Paste Buffer Into Fig Paste Buffer as New m Delete Buffer Clicking on a buffer in the display area makes it the active buffer i e the one that will be used for paste commands executed with the Buffers Menu or the buttons at the bottom of the dialog Double clicking on a buffer causes its contents to be pasted to the active image this is a quick way of executing the Paste Buffer command At the bottom of the dialog are four buttons The operations they perform can also be accessed from the Buffers Menu that you get by right clicking on the active buffer e Paste Buffer This command pastes the contents of the selected buffer into the active image as a floating selection The only difference between this and the ordinary Paste command is that it uses the selected buffer rather than the global clipboard bu
441. yer AS soon as a guide Is created the Move tool is selected and the mouse pointer turns to a move icon Guide behaviour depends on the Affect mode selected in the Move tool When the Transform Layer mode is selected the mouse pointer turns to a small hand when it reaches a guide that becomes red and active You can then move it by a click and drag When the Transform Selection mode is selected you can place a guide but you can no longer move it after quitting it To make positioning easier you can magnetize guides with the option Snap to Guides You can abort displaying guides without removing them by the option Show Guides A way of representing color in the form rrggbb where rr represents red gg green and bb blue Commonly used in web design Hue Saturation Value a way of representing color The Hue is the color like red or blue the Saturation is how strong the color is and the Value is the brightness This is sometimes called HSB or Hue Saturation Brightness Image Hoses are special brushes that contain many different frames An example of this might be a footstep brush that contains two images One of a left footprint and one of a right footprint During the application of this hypothetical hose brush one would see the left footprint followed by that of the right in a continuous fashion This method of animation for brushes Is very powerful This paint mode renders each brush stroke directly onto the active layer If incremen
442. yer Mask from Selection The Subtract from Selection command converts the layer mask of the active layer into a selection which is subtracted from the selection that is already active in the image White areas of the layer mask are selected black areas are not selected and gray areas are converted into feathered selections The layer mask itself is not modified by this command Activating the Command e You can access this command from the image menubar through Layer Mask Subtract from Selection e or from the pop up menu you get by right clicking on the active layer in the Layers Dialog Intersect Layer Mask with Selection The Intersect with Selection command converts the layer mask of the active layer into a selection The intersection of this selection and the selection that is already active form the new selection for the image White areas of the layer mask are selected black areas are not selected and gray areas are converted into feathered selections The layer mask itself is not modified by this command Activating the Command e You can access this command from the image menubar through Layer Mask Intersect with Selection e or from the pop up menu you get by right clicking on the active layer in the Layers Dialog The Transparency Submenu of the Layer menu GNU Image Manipulation Program Page 272 of 421 Generated by docbook2odf pe O N 4 O O 2 S O xe a 2 xe o G 3 S o

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