Home

Here

1. a Ni iy IM IV re 64 956 26 GY 29411 Fig 8 Images of an Inconel step wedge with ASTM 2 2T penetrameters after digital high pass filtering Enhance details Top image without calibration only 2 4T hole are visible Bottom after application of fluoroscope calibration to the raw data Vertical banding is removed the steps are more homogeneous and 2 2T holes are visible between 0 2 and 0 5 inch thickness Exposure conditions are given in the displayed file name page 8 of 8
2. Integration Result uncalibrated gw O 65555 Integration Result C Apply temporal Filter Frame integration a swets CdS view Live view fraw se Fit to View iw 0 65535 Source calibration C Apply temporal Filter Frame integration OoOo seets Sd View automatic o 65535 ROT automatic Wiew auboniakic View Live View raw t Fit to view w Source 0x0 0 00 fps gv 0 65535 E bpp Full dynamic 14 bits dynamic Source calibration 12 bits dynamic 10 bits dynamic C Apply temporal Filter Frame integration 5 bits dynamic 6 bits dynamic 4 bits dynamic es Acquire Fig 5 All possibilities to control the image display in the V2 main window top selection of different data streams middle image display with different zooming factors also adjustable via scroll wheel on the mouse bottom different settings for gray value stretching The numbers on the right hand side show the gray value range displayed between black and white Store to The button Reset in the V2 window resets the used IO library the button Setup calls the camera configuration window The layout of the set up window depends on the camera functionality and the implemented features of the ActiveX video components by the manufacturer of the camera driver For the FOculus camera this is shown in fig 6 There are only two very important settings for the fluoroscopic application which have to be adjusted correctly an
3. exe the program V2 exe should start smoothly and display the correct camera live data as shown in fig 3 The first line View in V2 exe allows configuring the image display in the main window All possible choices are shown in fig 5 The most right menu shown in fig 5 bottom needs some more explanation View automatic is the default gray scale presentation 1 e by scaling of the max 16 bit gray values in the image data to the 8 bit dynamic range of the display Here the complete image View is automatically scaled i e the minimum gray value scaled to black and the maximum gray page 3 of 8 value in the image is scaled to white The scaled gray value range is displayed on the most right side of the View line The top option ROI automatic is selected when a red rectangle is drawn by the mouse left mouse button pressed inside the main image window Than only the gray values inside this red rectangle are considered for automatic histogram scaling to full 8 bit of the display By pressing the right mouse button and moving the mouse the position of this red ROI rectangle can be moved inside image window The other settings shown in fig 5 bottom from 16 bpp full dynamic up to 4 bits dynamic fixed the Look up table LUT for image display to the indicated number of bits considered in the image gray values Live view raw EF Fit to view v 0 65535 Live View i rar i Live View Filtered Source
4. 40 5 00 fps gv 1 43 Source calibration 0 1 OK Abbrechen C Apply temporal Filter E Frame integration soreo is Fig 6 On the right hand side is the camera control windows shown for FOculus FO 442SB camera after pressing the button Setup in the V2 main window Only the tab Net Video Control is of importance the tab NET camera Control should not be changed There are only two parameters which have to be adjusted and checked every time the camera is reconnected with the Firewire interface Brightness gray value of dark image without exposure and Stutter which determines the light exposure time of each camera frame All the other parameters should not be changed The correct settings are shown here for the BAM camera working at 200 ms exposure time shutter 1829 and a dark level of 1 2 gray values brightness 555 The other important setting parameter electronic Shutter will set the exposure time for the single camera frame This value is an encrypted value derived from the frame time in msec Depending on the selected frame time the correct Brightness setting will change because the dark signal of the CCD chip will increase with increasing frame exposure time So it is usefully to operate the fluoroscope only with a very limited number of different shutter settings because also the fluoroscope calibration depends on this setting Depending on th
5. BAM VIII 35 July 22nd 2009 Dr Uwe Zscherpel Dr O Alekseychuk http www kb bam de alex v2 Manual for installation of software image acquisition via Firewire and detector calibration This manual provides details to operate the Radio5000 Fluoroscope 1 Software and hardware installation The selected Firewire camera FOculus FO442SB requires special drivers to operate under Windows operating systems The manufacturer NET GmbH in Germany provides on its web site the latest version http www net gmbh com The following files are available today for download concerning the FO442SB camera 1 FOcontrol_Install_4 0 3 0 exe the camera drivers and the demo application FOcontrol exe 2 FOControl_V3 0 7 0_manual pdf the user manual for the demo application FOcontrol exe 3 NET_FOculus_S_user_manual_v1 15_OOl pdf the detailed description of the FO442SB camera specifications and the software and driver installation The first file has to be started once at the computer to install all necessary drivers and the demo application FOcontrol exe Finally there will be installed a link to this demo application on the desktop Please reconnect the camera after this software installation to the hot pluggable Firewire interface ONLY THEN all necessary windows drivers will be installed too and the camera is visible under the system gt hardware gt device manager as image processing device with the name NET GmbH 1394 Digital Cam
6. a Estra function HeH HET GmbH FO4dS0 FF 42500101 ao THEIA Forma Hinda oprerrs ras e l a a e T ae o NET GmbH for Basic camera tests Fig 1 FOcontrol exe demo application The application V2 exe was developed especially for data acquisition with the Radio5000 fluoroscope at BAM Berlin and released under GNU public domain This program does not need any installation just start V2 exe from a suitable directory The V2 exe file needs some more DLL libraries to run Mvr exe 691 KE 18 07 2009 13 51 S QtCore4 dll 2031 KE 27 03 2006 16 38 S otauid al 2935 KB 19 02 2008 21 29 8 mainquern10 dll l6 kB Z7 12 2007 17 23 Fig 2 V2 acquisition program and its components There is no installation required just start V2 exe and keep all 4 files in the same directory The main window as shown in fig 3 appears on the desktop after starting the application V2 exe Clicking the button About shows the window of fig 4 my 610x662 View Live View raw v Fit to view 8 bits dynamic v 0 255 Source Device 0 x 1388x1040 6 49 fps gv 0 255 E Source calibration m C Apply temporal filter 5 Frame integration Store to Fig 3 Main window of the V2 exe application with live camera image camera recognized as Device 0 image size 1388 x 1040 pixels 8Bit gray values 0 255 in the live image frame rate 6 49 frames per second pag
7. ans of real time Frame averaging of a Frame stream e g video stream Additionally it is able to perform pixel correction spatial and temporal and Finally the result can be saved as a standard 16 bit gre level TIFF imge 2 should work with all cameras which have standard DirectShow Windows driver This software is licensed under terms and conditions of GNU General Public License as published by Free Software Foundation 2 is designed and written by Dr Oleksandr 4lekseychuk foleksandr alekseychuk bam de in German Federal Institute For Materials Research and Testing B4M Please visit the project page at http jw kb bam det alexiwz For recent updates and additional information You are currently using a version Build on Jul 21 2009 codename LUNAR Fig 4 Window About for the BAM software V2 exe with information on license and availability There can be several circumstances where the V2 exe program just crashes This can be coursed by software bugs between the used public domain library for Video I O and the DLLs provided by the camera manufacturer This is outside the program V2 exe and cannot be prevented completely It can also happen that the camera is recognized but no data are transferred 0 fps and black image window This happens mostly after reconnection of the camera to the system In this case start the FOcontrol exe application and start and stop the camera as shown in fig 1 After exiting the FOControl
8. d checked every time the camera is connected again via Firewire These are the settings for Brightness and Shutter all the other parameters should be as default and not changed For details see the camera manual NET_FOculus_S_user_manual_v1 15_O001 pdf If Brightness and Shutter is not set correctly images as shown in fig 3 are acquired with clipped gray values Zero value in blue max value of 255 in red Information kept in the page 4 of 8 marked blue and red regions are lost in the image and cannot by enhanced by any frame integration So it is important to set the Brightness level correctly this will avoid any blue colored pixels showing gray values of zero The optimum setting is shown in Fig 6 Brightness 555 the electronic background of the camera without light is between 1 and 2 gray values The exact brightness value depends on each camera and its actual temperature O lt Eigenschaften Are el oer ze NET Camera Control NET Video Control Brightness t 555 0 1023 Ean fo 0 511 Auto Exposure th 50 0 100 Shutter lt j 1823 1 3843 Ey J peee 0 ok Saturation Haee 0 eS he ke eS ae hc Shapness sh D Gamma White Balance A 1st Push CS mai 0 0 Register Read Write Register Address F0000400 Read Register Yalue 00000000 Write Default View Live View raw vi Fit to View ROI automatic v 1 2 Source Device 0 bet 1388x10
9. e available X ray power and distances the frame exposure time should be long enough to have enough signal in the middle of the image At BAM we are using an X ray tube up to 225 kV and 1 8 kW at 700 mm distance For this source a frame exposure time of 200 ms which means 5 frames per second unprocessed raw data was always the optimum shutter 1829 In tab 1 typical shutter values and the corresponding frame exposure time is provided which have been calculated from the formula given in NET_FOculus_S_user_manual_v1 15_O001 pdf page 5 of 8 1394 Shutter Frame 1394 Shutter Frame exposure time exposure time Tab 1 Frame exposure time of the CCD chip in dependence of the shutter value setting in the camera software control tab view Live View Filtered s Fit to view se view automatic ol 15 100 Source Device g 1358x1040 2 00 fps ov 14 129 Setup Reset About Source calibration E 4E4 calibration txt is Beep on finish Apply temporal filter 5 Frame integration 50 o q Store to BE T4E4 Flatfield_cal tir a Interrupt Fig 7 Example of ongoing integration with V2 9 frames of 50 are already done using all features including calibration The acquired gray values of a single frame are between 14 and 129 so no clipping is shown and the source calibration should work also The computer load by the applied temporal filtering of 5 frames and image integration decreases the frame rate from 5 fps to 2
10. e 2 of 8 The V2 exe application uses standard Windows video streams via DirectShow and ActiveX In this way a wide range of video devices with live data streams are supported at the moment only with 8 Bit color or gray scale images The basic functions of V2 are as following 1 Display of live video in the main window with markers on information clipping gray values of O are displayed in blue color gray values of 255 in red color see fig 3 2 Control of camera settings via Setup button 3 Integration of multiple fames to 16 Bit gray scale images by averaging of 8 Bit frames and scaling to 16 bits for increased dynamic and signal to noise ratio 4 Temporal median filtering prior averaging for suppression of directly converted X ray photons reaching the CCD chip despite all of the lead shielding Selection of file name for storage of integrated images as standard 16 bit TIFF image 6 Calibration of the integrated raw images via calibration set up file see chapter 3 for reduction of electronic background so called dark image and in homogeneities between single pixels via additionally multiple gain images bright images with flat field X ray exposure of different intensities It allows also replacing bad pixels 7 The calibration procedure file and functionality is the same as used in ISee via the menu Image gt Adjust pixels i a About V2 frame averager 2 is a software For acquisition of still images by me
11. era When the device is shown in the manager window without a yellow exclamation mark the camera is ready for operation A sound beep should be heard from the computer every time the camera is connected or disconnected on the running windows system The camera power has to be provided by the Firewire cable A standard 6 pin IEEE 1394 cable and connector at the computer provide this power the smaller 4 pin connectors found on laptops does not Here adapter cables from 4 pin to 6 pin with an additionally power supply of 12 V should be used DANGER Please connect the 6 pin cable only side correctly With brutal force the steel frame of the 6 pin connector can be expanded to such a size that the cable can be plugged in turned by 180 If than the power is provided to the camera the exit circuit of the Firewire interface inside the camera is definitely destroyed and the camera has to be sent for repair to the manufacturer Net GmbH Be carefully 2 Software operation and image acquisition As next step start from the FOcontrol application the desktop link Select the set ups as shown in fig 1 Clicking the button start camera will show a live camera image stop camera will erase this image from the window If all works fine please stop the camera and exit FOControl For more information see the manual FOControl_V3 0 7 0_manual pdf page 1 of 8 BA rocontrol 3 0 0 0 SS ee ea ae alia i MA Sayer Le ti an Image Capore Cori Tasi
12. for the BAM fluoroscope is given here adjust_black Dark2 200ms 240s tif Fe5mm 220kV 1mA 700mm 200ms 180s tif Fe5mm 220kV 2mA 700mm 200ms 120s tif Fe5mm 220kV 4mA 700mm 200ms 120s tif Fe5mm 220kV 8mA 700mm 200ms 60s tif A steel plate of 5mm was used for calibration Beside the dark image 4 white images were generated for calibration of the full dynamic range With 8 mA at 700 mm distance no detector saturation was obtained The other darker images should have gray values linearly increasing from the darkest to the brightest image It is usefully to have at least the double integration time for detector calibration as used later for image acquisition If the source to detector distance will change some artifacts in the detector calibration will show because of the changes X ray source shading overlaying the internal detector shading mainly from objective page 7 of 8 In Fig 8 the improvement of image quality is shown before and after calibration Of course during acquisition of images for fluoroscope calibration the calibration function in V2 has to be deactivated e g no source calibration text file as in fig 4 F eh Is 1 eae An F L rn LE i 7 oth E oh wal 7 Li bes ate e l Talar Wiar at ar fee We a da2 We w 1 a ee T Wir im Pir TEN n He n ax MaRa T amp Aa y a d ATA 4 F 967 500 GV 33093 _ SNR 4 Mal Ea d Eel FA PAWIACA Ci olx o MaRa Twll gil E y o AA
13. fps So an overall exposure time of 50x0 2s 10s is integrated but the time needed for this integration is 50x0 5s 25s So a faster computer will save some overhead exposure time In Fig 7 a snapshot on an ongoing flatfield exposure is shown page 6 of 8 3 Calibration of fluoroscope As shown in fig 7 the calibration is controlled via a simple text file The content of the used file here is as following ad EditPad oF amp Big AX a al E calibration tet fSadjust black dark 200ms SOframes tit right 200ms SO0frames tit Inset 65 1 EditPad Copyright C 1996 1997 by z Fig 7 Principle of fluoroscope calibration via text file containing keywords and image names used for gray value correction The keyword adjust_black control that the first image dark_200ms_5Oframes tif is used to subtract any dark offset from each of the following white images All the following images here only one image bright_200ms_SOframes tif with a homogeneous exposure at the sceen is used are used for pixel wise linear interpolation of the image to be calibrated for equalization of the individual pixel responses to provide the same median gray value of the calibration image For more details on image calibration see for documentation included within the See package see http www kb bam de alex ic There identical functions can be used via Image gt Adjust pixels A typical calibration text file

Here

Contents

Download Pdf Manuals

Related Search

Related Contents