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Meridian 2 user guide and technical specification

1. NMENENENENMNHR OEE E NKE RKEKEMMMMMMMMMMMMMMMNMNME NN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 43 of 93 Attribute Record ATTREC 14 for road nodes Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique ID for record VAL TYPE 09 10 A2 OD VALUE 11 23 A13 Unique ID OSODR for node VAL TYPE 24 25 A2 FC VALUE 26 29 14 Feature code VAL_TYPE Wa A2 JN VALUE Ke A Junction name DIVIDER ru A1 VAL_TYPE Ka A2 SN VALUE I A Settlement name DIVIDER i A1 VALUE TYPE a A2 RT VALUE e A1 Y Roundabout CONT MARK is I1 0 No further records or 1 Continuation record EOR Ka A1 96 Record terminator NOTE variable integer Record example 140000230D03DF42CKOVTEGFC3500NP03POO1J945LPCABATPOO142WFUP80AA0POO1CV33LKPCBXE1 00JNM27 J2NSNSOUTHAMPTONNRTYOS 1 2 3 4 5 6 y 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template NOTE 1 JN SN and RT records will only be included where a name exists CO V V i OG Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 44 of 93 Attribute Record ATTREC 14 for administrative area links county district coastline and neat line Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 l4
2. e INSERT entity type group Attribute number 0 e Layer name group 8 e Block name group 2 e Xcoordinate group 10 e Y coordinate group 20 e Xscale factor 41 optional e Y scale factor 42 optional e Orientation group 50 optional if 0 b LINE entities these consist of e LINE entity type group 0 e Layer name group 8 e Start X coordinate group 10 e Start Y coordinate group 20 e End X coordinate group 11 e End Y coordinate group 21 RN Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 72 of 93 c POLYLINE entities these consist of e POLYLINE entity type group 0 e Layer name group 8 e Vertices follow flag group 66 e Polyline flags group 70 optional e Anumber of VERTEX entities shown below e SEQEND group 0 d VERTEX entities these consist of e VERTEX entity type group 0 e Layer name group 8 e Xcoordinate group 10 e Y coordinate group 20 e Z coordinate group 30 e TEXT entities these consist of e TEXT entity type group 0 e Layer name group 8 e Xcoordinate group 10 e Y coordinate group 20 e Text height group 40 e Text string group 1 e Justify type group 72 optional if 0 e Justify type group 73 optional if 0 e Orientation group 50 optional if 0 e Text style group 7 optional e Align X group 11 only present if Justify type group is present and
3. DXF is designed for use with Autodesk Ltd CAD software particularly AutoCAD D X F The parameters defining colours line styles text styles symbols and so on are embedded within the DXF file as is customary with this CAD format Please check with your supplier if you are unsure of your CAD system s compatibility with Meridian 2 Meridian is also available as data in Mid Mif and shapefile formats which require specific software such as Maplnfo Professional or ArcView Supply Meridian 2 supply options The options for data supply are as follows e Combined theme all layers e Communication theme roads and railways boundaries and coastline e Topographic theme boundaries and coastline developed land use areas DLUAs cartographic names hydrology woodlands and gridded height NOTE Gridded height is supplied with the Meridian 2 supply options but on a separate CD 0 o NENENENENMNAEARK 9SS g SEKRK AeKgA9MNNNE ERE R4 XA GENI Meridian 2 user guide chapter 1 v5 2 02 2007 Crown copyright Page 6 of 93 All themes are available as e Complete national cover of Great Britain 2 856 tiles e England e Scotland e Wales These areas correspond with Nomenclature des Unites Territoriales Statistique NUTS Level 1 Areas e 10km by 10 km tiles Meridian 2 supply formats Meridian 2 is available in e NTF BS 7567 v2 0 Level 3 or e DXF conforming to AutoCAD relea
4. The section consists of two parts 1 Section Header Record SECHREC this gives the National Grid coordinates of the section and on unformatted media informs the customer that a new section is starting 2 Section body this comprises all the features within the section Version management Each version and release of all Meridian 2 products is defined by a unique product version number and release number these are reflected in this technical specification The product version number relates to the specification of the data being supplied and the release number relates to the release of the product The product version number takes the form xx yy where xx is the major product number and yy is the minor change number Thus version 02 00 would indicate that this is the major product version 02 and that the 00 indicates no minor amendment to the product specification The release number takes the form xx yy where xx is the sequential release within a year and yy is the year of the release Thus release 01 01 would indicate that this is the first data release in 2001 The product version number and the release number are specified in the Database Header Record DBHREC as supplied in NTF RN Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 30 of 93 General e The following are the record definitions for the transfer of Meridian 2 data in NTF e Volume Header Record VOLHDREC e Database Header R
5. e road name e number of links at node e road number and e level of link at node and e trunk road indicator e settlement name If a feature moves by more than the specified tolerance then the OSODR for the feature will be deleted and a new OSODR allocated to that feature If a feature is deleted from the Roads database then the OSODR allocated to that feature will cease to exist and will not be reallocated Link level at node The level field in Node Record 16 indicates for roads the relative height relationship between intersecting links at a node It does not relate to ground surface level If a road over a bridge can be accessed then a level value of 0 is used a value of 1 used when there is no access from one road to the other at an intersection See figure 2 2 Figure 2 2 Grade separation In this instance the single node will show a level 0 for all links in Node Record 16 as it is possible to access any carriageway from any approach road A bridge over a road that cannot be accessed will show a level value of 1 Proper name PN attribute This attribute defines the road name associated with any link in the Roads database If a link does not have a proper name then the attribute will not be present Where the road is otherwise not named and part of a named estate the estate name will be allocated to the road Roundabout RT attribute This attribute defines whether a node is a generalised representation of a
6. 14 for road imks n 43 Attribute Record ATTREC 14 for road nodes eee 44 Attribute Record ATTREC 14 for administrative area links county district coastline and Nearline j 45 Attribute Record AT TREC 14 for administrative area points and or seeds 46 Attribute Record ATTREC 14 for nodes administrative areas DLUA coastline and railway hydrology and woodlands and or edge nodes all layers ce cee eeeeeeeeeeeeeeeeeeeeeeeetnaeeeeeeaaes 47 Attribute Record ATTREC 14 for DLUA links sssssem mI 47 Attribute Record ATTREC 14 for DLUA points and or seede ss nsnnnseeeeennnn renees eerren reee 47 Attribute Record ATTREC 14 for cartographic name Text 48 Attribute Record ATTREC 14 for railway linkS sess 48 Attribute Record ATTREC 14 for railway station nodes sseneeeseseneneneeeeenrnrnenssrrerrnn ren 49 Attribute Record ATTREC 14 for water feature river small eseeesess 49 Attribute Record ATTREC 14 for water area sees nenn 50 Attribute Record ATTREC 14 for administrative area points and or seeds 50 Attribute Record ATTREC 14 for gridded height point sssssnnnseeesennnnnnseenennnrrnnnnnsseennrnnnenno 51 Point Feature Record POINTREC 15 sss nennen 51 Node Record NODEREC 106 eire derer eoo EERSTEN 52 Tw
7. An item of detail within a map that can be either a point or symbol a line or text feature classification record A specific named NTF record that lists the feature codes in use in the current database feature code FC An alphanumeric attribute code used in digital map data to describe each feature in terms of the object surveyed its representation on the map or both feature serial number FSN A number used as a feature identifier usually allocated on a sequential basis For example the order in which features are digitised field A specific part of a record containing a unit of data such as the date of digitising The unit of data may be a data element or a data item In NTF a field is a subdivision of a physical record Every field has a name and a predefined interpretation file An organised collection of related records The records on a file may be related by a specific purpose format or data source the records may or may not be arranged in sequence A file may consist of records fields words bytes characters or bits font The style of text character used by a printer or plotter format The specified arrangement of data For example the layout of a printed document the arrangement of the parts of a computer instruction the arrangement of data in a record geographical information system GIS A system for capturing storing checking integrating analysing and displaying data that is spatially referenced
8. Field Position Format Value example Description REC_DESC 01 02 A2 45 TEXR_ID 03 08 l6 Unique text representation record identifier cross reference from TEXTPOS FONT 09 12 l4 0004 Text font Identity TEXT HT 13 15 R3 1 Text height in millimetres DIG POSTN 16 16 I1 Digitising position 0 8 ORIENT 17 20 R4 1 Anticlockwise from grid east CONT_MARK 21 21 I1 0 No further records EOR 22 22 A1 Record terminator Record example 450000070004020300000 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template Comment Record COMMENT 90 Field Position Format Value example Description REC DESC 01 02 A2 90 RECORD TYPE 03 04 12 Changed NTF record type RECORD_ID 05 17 A13 Unique ID OSODR CHANGE_TYPE 18 18 A1 DorlorU Type of change CONT_MARK 19 19 11 0 No further records EOR 20 20 A1 Record terminator Record example 9023017945LPCABAXU0S 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template Field Position Format Value example Description REC DESC 01 02 A2 90 FREE TEXT 03 A CONT MARK bs I1 0 No further records EOR prs A1 96 Record terminator NOTE variable integer Record example 90 TILEOS 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template RN Meridian
9. You should check the terms and conditions with us before using the data It is also the responsibility of the holder of the digital map data to ensure that any plotted or printed output contains the required copyright and database acknowledgements in a conspicuous position All aspects of Meridian 2 discussed in this user guide relate to Meridian 2 in both BS7567 NTF v2 0 and DXF AutoCAD Release 12 If the two format versions differ in their treatment of a particular aspect the specific differences will be stated Trademarks Ordnance Survey the OS Symbol Land Form PANORAMA Land Line Landranger and Strategi are registered trademarks and Boundary Line and Meridian are trademarks of Ordnance Survey the national mapping agency of Great Britain Arclnfo ArcView and ESRI are registered trademarks of Environmental Systems Research Institute Inc AutoCAD and Autodesk are registered trademarks and DXF is a trademark of Autodesk Inc Helvetica and Univers are registered trademarks and Times is a trademark of Heidelberger Druckmaschinen AG MapInfo is a registered trademark of MapInfo Corporation Back up provision of the product You are advised to copy the supplied data to a back up medium Using this guide The documentation is supplied in portable document format PDF only Free Adobe Acrobat Reader software which displays the guide incorporates search and zoom facilities and allows you to navigate within Hyperlinks are
10. 1 2 16776960 Brush 2 13697000 16777215 Pen 1 2 16777215 Brush 2 13696976 16777215 Pen 1 24 0 Pen 1 23 0 Symbol 34 0 9 Symbol 34 0 9 Symbol 34 0 9 Symbol 34 0 9 Pen 1 2 0 Pen 1 2 4227327 Symbol 34 4227327 9 Symbol 34 4227327 9 Style Pen 1 1 16768208 Brush 2 16762032 16777215 Symbol 34 16768208 9 Symbol 34 16768208 9 Symbol 34 16768208 9 Pen 1 2 16768208 RN Meridian 2 technical specification annexe B v5 2 02 2007 Crown copyright Page 91 of 93 Railways Feature Feature names code 6140 Railway 6142 Railway tunnelled 6155 Station point 6731 Railway edge node 6730 Railway node Cartographic names Feature Feature names code 6551 Station name 6500 Names Hydrology Feature Feature names code 6223 Water feature river small 6224 Water feature river medium 6225 Water feature river large 6230 Water feature hidden 6231 Water feature aqueduct 6232 Water feature dark link 6243 Water feature canal 6255 Area water lake polygon 6292 Area water seed 6770 Water feature node 6771 Area water node 6772 Area water edge node 6773 Water feature edge node 6803 Area water neat line 6552 Water Text Type Line Line Symbol Symbol Symbol Type Text Text Type Line Line Line Line Line Line Line Polygon Symbol Symbol Symbol Symbol Symbol Line Text Style Pen 2 2 0 Pen 2 3 0 Sy
11. 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 56 of 93 Volume Terminator Record VOLTERM 99 Field Position Format Value example Description _DESC 01 02 A2 99 FREE_TEXT 03 A See note below CONT_VOL 1 1 I1 0 No continuation volume or 1 or continuation volume follows EOR 2 2 A1 Record terminator NOTES If there are further volume s to follow then the FREE_TEXT field comprises the following message End Of Volume nn Transfer Set Continues On Volume nn 1 If there are no further volumes then the FREE_TEXT field will read End Of Transfer Set variable integer Record examples 99End Of Volume 01 Transfer Set Continues On Volume 021 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template 99End Of Transfer Set0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Lot of TTT P p p TI pb P L TI Hh Template RN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 57 of 93 Chapter5 DXF explained The purpose of this chapter and chapter 6 is to e Provide a brief description of the presentation of Meridian 2 in the DXF transfer format e Data Exchange Format DXF conforming to AutoCAD release 12 with extended entity data As part of this description data structure diagrams are used to giv
12. 40 100 0 9 SATTMODE 70 1 9 STEXTSIZE 40 1 0 9 STEXTSTYLE 7 STANDARD 9 SCELTYPE 6 BYLAYER 9 CECOLOR 62 256 9 LUNITS 70 2 9 SLUPREC 70 1 9 SAUPREC 70 1 9 SANGBASE 50 0 0 9 E Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 65 of 93 X drawing limit upper right corner in WCS Y drawing limit upper right corner in WCS Global linetype scale Attribute visibility This sets attributes to on when the file is open Default text height Current text style name Entity linetype name Entity colour name Indicates colour ID BY LAYER Units format for coordinates and distances Units precision for coordinates and distances Units precision for angles Angle zero direction SANGDIR Angle rotation 70 0 1 clockwise angles 0 anti clockwise angles 9 PDMODE Point display mode 70 1 9 SPDSIZE Point display size 40 05 0 9 PLINEGEN Sets the linetype pattern generation around the vertices of a 2 dimensional Polyline 70 1 0 ENDSEC End of Section Tables Figure 6 3 Level 2 Key o o optional TABLES SECTION o LINETYPE TABLE Figure 6 4 SECTION START ENDSEC GROUP SECTION GROUP TABLES GROUP RN Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 66 of 93 The Tables Section will follow the Header Section and will contain three tables e Linety
13. 93
14. AE AA AKEB hB KBHBRKERNMNMNMNNNE EN Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 29 of 93 01 Volume header record 01 01 Volume header record 02 02 Database header record 40 Attribute description record Remainder part tile 1 data 05 Feature classification record 07 Section header record 99 Volume termination record Part tile 1 data 01 Volume header record 01 02 Database header record 99 Volume termination record m 40 Attribute description record 05 Feature classification record 07 Section header record 99 End Of Volume 01 Transfer Set Continues On Volume 021 Tile 2 data 99 Volume termination record 99End Of Transfer Set 0 The beginning of each transfer set is structured with the following introductory or leading records Database Header Record DBHREC this gives details of 1 The database name 2 NTF release date 3 Feature classification table name 4 Release date that applies to the whole of the transfer set Attribute Description Record ATTDESC this lists and gives a description of the attributes that can be applied to features within the transfer set Feature Classification Record FEATCLASS this lists and gives descriptions of all possible feature codes for the transfer set These introductory records are followed by the data requested by the customer that are contained in the section
15. Format Value example Description REC_DESC 01 02 A2 01 DONOR 03 22 A20 ORDNANCE SURVEY lt 5S gt RECIPIENT 23 42 A20 lt 20S gt Not used TRANDATE 43 50 DATE yyyymmdd Supply date SERIAL 51 54 l4 0000 Not used VOLNUM 55 56 I2 nn Volume number 01 to 99 NTFLEVEL 57 57 I1 3 NTF Level 3 NTFVER 58 61 R4 2 0200 NTF Version 2 0 NTFOR 62 62 A1 V Variable length records EOR 63 63 A1 96 Sets EOR to 96 on formatted media or lt S gt or default 96 for formatted media DIVIDER 64 64 A1 Divider used to terminate variable length text fields CONT_MARK 65 65 I1 0 No further records EOR 66 66 A1 96 Record terminator Record example O1ORDNANCE SURVEY 2001121000000130200V 0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template kL Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 39 of 93 Database Header Record DBHREC 02 Record 1 Field Position Format Value example Description REC_DESC 01 02 A2 02 Record type identifier DBNAME 03 22 A20 Meridian_02 01 lt 6S gt Database name DDNAME 23 42 A20 DEFAULT_02 00 lt 7S gt Standard data dictionary name DDATE 43 50 DATE 19920515 Release date of NTF version being used DDBASE 51 70 A20 lt 20S gt Not used DDBDATE 71 78 DATE 00000000 Not used CONT_MARK 79 79 I1 1 Continuation record follows EOR 80 80 A1 96 Record terminator Record 2 Field
16. annexe A v5 2 02 2007 Crown copyright Page 89 of 93 Annexe B Meridian 2 MapInfo Mid Mif layers This section contains a list of all the valid features used with Meridian 2 The list contains a description of each feature code its feature name its feature type and list of the style information required to create an output Each feature layer then contains other information as attributes Important information Certain feature codes that are used and defined in NTF are not required or used in MapInfo Some examples of this are 3501 Road Edge Node 6411 County Seed 6710 Boundary Node unspecified Other feature codes that are not u002sed 6415 6711 6800 6741 6310 6720 6721 6801 6731 6730 6292 6770 6771 6772 6773 6803 6663 6802 6750 6751 and 6740 File Description Data type Feature code 1 motorway Line 3000 2 a_road Line 3001 3 b_road Line 3002 4 minor_rd Line 3004 5 junction Node 3500 6 rndabout Node 3500 7 settlemt Node 3500 8 roadnode Node 3500 9 rail_In General 6140 6142 10 station General 6155 11 county General 6401 12 district General 6403 13 coast In General 6200 14 admin In General 6401 6403 6405 15 dlua General 6300 16 text General 6551 6500 6405 6552 17 river General 6223 6224 6225 6230 6231 6232 6243 18 lake General 6255 19 woodland General 6664 20 height Height 6762 RN Meridian 2 technical specification annexe B v5 2 02 2007 Crown copyright Page 9
17. by 100 km Each of these squares has a unique two letter reference for example TG in the diagram below Each Meridian 2 10 km by 10 km tile is HP described by adding a two digit reference to 4 the 100 km by 100 km square reference HT HU with the easting first followed by the UT northing for example TG23 HW HX HY HZ For additional information on how to use the Se National Grid visit Ordnance Survey s NA NB NC ND website at GU WE http www ordnancesurvey co uk NF NG NH NJ NK fI j NL NMZNN NO i Ne NRNS NT NU i NW INX NY NZ SC Sp SE A 100 km by 100 km square TG Fame SH SJ SK TF TG m SM SN SO SP TL 7M P SR eer au TG TR j o CEP S sv sWisx sY Sz v 2 D o 10 km by 10 km square TG 23 RN Meridian 2 user guide chapter 3 v5 2 02 2007 Crown copyright Page 10 of 93 Annexe A Product and service performance report form Ordnance Survey welcomes feedback from its customers about Meridian 2 If you would like to share your thoughts with us please print a copy of this form and when completed post or fax it to the address below Be MI ERO TEUER jorer iapcuM E A el Quotation or order reference sessssssesssssseeeeeeehenneennhnnnhesnnirhess nasi sssb tis sa sese
18. identified in ISO 19113 Geographic Information Quality principles 2002 NOTE According to North America Standards Institute although ISO 19113 2002 is applicable to digital geographic data its principles can be extended to many other forms of geographic data such as maps charts and textual documents ISO 19113 2002 does not attempt to define a minimum acceptable level of quality for geographic data If you are unfamiliar with any words or terms used and require clarification please refer to the glossary at the end of the document RN Meridian 2 technical specification introduction v5 2 02 2007 Crown copyright Page 15 of 93 Chapter1 Overview of Meridian 2 Using this technical specification Please refer to the glossary if you are unfamiliar with any of the words or terms used The glossary can be found at annexe A attached after the technical specification All aspects of Meridian 2 discussed in this technical specification relate to Meridian 2 in both BS 7567 NTF v2 0 and DXF AutoCAD Release 12 formats If the two format versions differ in their treatment of a particular aspect the specific differences will be stated Data overview Basic principles Links represent roads railways administrative areas coastline DLUA inland water and woodland area lines Nodes represent all intersections of links within each layer changes in attributes in links and link ends Each feature has associated geometry this may
19. line cannot cross from one tile 10 km by 10 km square to the next it is split on the tile edge see Unique identifiers All linear features are continuous Cartographic gaps are closed during the digitising process Coordinates Coordinate values and the number of coordinate pairs in a feature are transferred in the GEOMETRY 1 NTF record All coordinates within the data are expressed as strings of five numeric characters Leading zeros are present to complete the five characters All coordinates are measured from the local origin which is the south west corner of the tile To convert coordinate data to full National Grid coordinates add the coordinates of the feature to those of the south west corner of the tile The south west corner coordinates are contained within the X_ORIG and Y ORIG fields of the Section Header Record SECHREC 07 Bearings Bearings are transferred in the ORIENT field of the Node Record NODEREC Bearings are National Grid bearings in degrees measured clockwise from grid north The start of line bearing indicated by a value of 1 in the DIR field of the Node Record NODEREC is the bearing of the first segment of the line The direction is from the start of the line to the next pair of coordinates or if there are only two coordinate pairs from the start to the end of the line The end of line bearing indicated by a 2 in the DIR field is the bearing of the last segment of the line
20. more links with the same unique identifier see figure 3 1 and figure 3 2 Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 34 of 93 Record IDs The identifying fields for each NTF record for example NODE ID for NODEREC LINE ID for LINEREC and so on are unique within each individual section tile supplied They are not maintained between supplies Figure 3 1 Example of a unique identifier OSODR Figure 3 2 Example of unique identifier a railway and railway station Tile id ST68 LINE ID 41 LINE ID 62 OSODR ODJ945LPCABAX Tile id ST88 LINE ID 71 D LINE_ID 130 LINE_ID 22 Tile id ST86 Tile id NT68 NODE_ID 23 LINE_ID 41 Railway identifier 3823110682322 332110684101 Railway station identifier Tile id NT88 LINE_ID 153 LINE_ID 43 Tile id NT86 Feature layers This section contains a list of all the valid features used with Meridian 2 The list contains a description of each feature its feature type its feature code FC and a list of the attributes other than FC which can be associated with that feature The list is segmented by feature layer NOTE All features carry the attribute FC as the feature code Roads Feature description Motorway A road B road Minor road Road node Road edge node Railways Feature description Railway Tunnelled railway Railway station Railway node
21. node within the national roads dataset e Railway and railway station identifiers These uniquely identify any railway link or railway station within the national Meridian 2 database e Developed land use area identifier This uniquely identifies any DLUA seed point within the national Meridian 2 database e Global identifier This uniquely identifies any administrative area seed point within the 10 km by 10 km tile e Forestry identifier This identifies any forestry area seed point e Hydrology identifier This identifies any hydrology area seed point The unique identifiers are unique references and will be maintained except where there has been significant change to a feature The unique identifier may refer to several links representing a linear object across tiles for example a road or a railway which may be chained together across tile edges Thus on adjoining tiles there may be two or more links with the same unique identifier See figure 2 3 Figure 2 3 Unique identifiers Tile id ST68 Tile id ST88 LINE ID 41 LINE ID 71 LINE ID 62 LINE ID 130 OSODR OMJ945LPCABAX Tile id ST86 Unique identifiers have been assigned to all existing roads links and nodes railway links and railway stations and to seed points for administrative areas DLUAs hydrology inland water and woodlands Any of these features that are new to Meridian 2 after the initial allocation will be assigned an
22. railway station attribute names are shown as independent text features and located near the feature that they describe Place names are collapsed from double banked treble banked or composite text to a single text feature with all the text as one string The text font and text height in metres have been used for these cartographic D X F names and are as layers separate from the feature with which they are associated These are the text font identifiers e 0001 has been used for railway text Times Roman non italic e 0002 has been used for settlement text Helvetica bold sans relief e 0003 has been used for water text Times Roman italic sans these are transferred with the text feature e 0004 has been used for town text Univers medium Roman condensed and text height in millimetres The Ordnance Survey convention for the digitising of names is as follows all names are digitised as point features given as X and Y National Grid coordinates The point has been digitised relative to the map feature it describes and the actual point represents one of the standard positions shown in figure 2 5 Figure 2 5 Standard Ordnance Survey text positions I peg 1 r I TES VC B n 2i 1 Ps na H A 2 L 1 P MS NET l l EC dE H H HI d ex ro 1 Log L 4 a S Lo 7 I I I 7 4 P e I I I I EE P H I I I 1 ot r 1 1 7 A M n 1 2 pow OFS EF E Fog Te 0o 4 Ka M
23. railway station nodes Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 l4 Feature code VAL TYPE 15 16 A2 SI VALUE 17 29 A13 Unique railway station identifier VAL TYPE 30 31 A2 PN VALUE 32 A Station name DIVIDER SM A1 Divider CONT_MARK 1 11 0 No further records or 1 or continuation record follows EOR T A1 Record terminator NOTE variable integer Record example 14000003FC6155914169010274901PNSandling Station 0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template Attribute Record ATTREC 14 for water feature river small Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 14 Feature code VAL_TYPE 15 16 A2 WI VALUE 17 29 A13 Unique water feature identifier VAL_TYPE 30 31 A2 PN VALUE 32 A River name optional DIVIDER Ka A1 Divider CONT_MARK I I1 0 No further records or 1 or continuation record follows EOR Kat A1 96 Record terminator NOTE variable integer Record example 14000003FC6223WI6169050279090PNRiver Lydden 0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template NOTE The WI identifier in the record exam
24. roundabout in the Meridian 2 road data If it is then the node will have a roundabout attribute with a value of Y Junction name JN attribute This attribute indicates the junction number of motorway junctions and the other classified roads at that junction The junction name is variable length text and is in the format M6J10A where M6 is the DfT road number and J10A indicates that this is the junction numbered 10A of the M6 If the junction has no junction number then that part of the junction name is not supplied RN Meridian 2 technical specification chapter 2 v5 2 02 2007 Crown copyright Page 22 of 93 There could be any number of roads at a junction therefore each classified road at that junction may be repeated in the junction name attribute An oblique character separates each road number and junction The following is an example of a junction name attribute M40J1 A40 A413 A4020 This attribute only applies to nodes If the node does not have a junction name then this attribute is not present Settlement name SN attribute This attribute defines the name of a location or settlement This name will be attached to the node that is closest to the position of the location or settlement Unique identifiers Unique identifiers are used to uniquely identify some features within Meridian 2 These are e OSODR attribute defines the Ordnance Survey Roads Database Reference OSODR This will uniquely identify any link or
25. sequence or relationship is implied Key een oneormore VOLUME o selection VOLHDREG 01 DATABASE VOLTER co FEATCLASS O5 preces SECTION SECHREG or SECTION BODY FEATURE o o POINT LINE NODE CARTOGRAPHIC FEATURES FEATURES FEATURES TEXT FEATURES POINT LINE TEXT FEATURE FEATURE FEATURE POINT FEATURE POINTREC GEOMETRY 1 ATTREC GEOMETRY1 POINTREC ATTREC 45 21 4 ate ore 44 LINE NODEREC FEATURE 16 LINEREC LINE ATTREC NODE 23 GEOMETRY 44 CONTINUATION RECORDS 00 GEOMETRY 1 GEOMETRY 21 BODY TEXTREC TEXTPOS TEXTREP GEOMETRY 1 ATTREC ETE 49 44 45 ot 44 CONTINUATION RECORDS oO Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 28 of 93 The governing body for the industry standard NTF is the British Standards Institution BSI Their address is British Standards Institution 389 Chiswick High Road LONDON Phone 44 0 20 8996 9000 Fax 44 0 20 8996 7001 Email cservices bsi global com W4 4AL Any queries relating to the Meridian 2 product should be referred to the Sales Information Helpdesk at the address given in contact details at the beginning of the user guide section Transfer set structure Record size NTF data is written to the output device in variable length records with a maximum record length of 80 characters which includes CONT MARK and EOR Record terminator EOR The end o
26. ss asd esses te less saei essa sa sana ssa Please record your comments or feedback in the space below We will acknowledge receipt of your form within three 3 working days and provide you with a full reply or a status report within 21 working days If you are posting this form please send it to Meridian 2 Product Manager Ordnance Survey Romsey Road SOUTHAMPTON SO16 4GU If you wish to return it by fax please dial 023 8079 2615 Any personal information that you supply with this report form will be used by Ordnance Survey only in the improvement of its products and services It will not be made available to third parties RN Meridian 2 user guide annexe A v5 2 02 2007 Crown copyright Page 11 of 93 Meridian 2 Technical specification Contents Section Introduction Chapier 1 Chapter 2 Chapter 3 Page no 15 Purpose of this specification and dsclaimer nn nnnnnn ent 15 erum c 15 BR le EE 15 Using thiS SPECIICAUOM RR 15 Overview Of MEN ET 2 c 16 Using this technical specification sssssssssesseeene nennen 16 RE Be I M H 16 srjMPneeLp m 16 Meridian 2 vector data structure nennen ertet 16 Meridian explained c
27. value as its partner on the adjacent tile All features having the same feature code are recorded on the same layer DXF D X F has a limited link and node structure within this structure a feature may be a name point or line Each feature is free standing that is its topological relationship to any other feature is not expressed in the data Other important data structure concepts include networks and polygons Networks are interconnecting features structurally related by means of an explicit point described as a node Between the nodes are series of non intersecting line segments described as links hence link and node see figure 2 1 This is of special interest in GIS where there may be a need to analyse the network in order to follow routes or to close polygons Proprietary GIS software can be used to build and maintain networks for linear features such as roads railways and so on and provides the functionality to store manage and manipulate this data The properties of Meridian 2 make it a suitable basis for users wishing to develop applications using Meridian 2 together with their own data As Meridian 2 is based on the National Grid there is a simple way of overlaying users own data provided the position is given within the National Grid The National Grid as it applies to Meridian 2 is explained in chapter 3 in the user guide section of this document MU V LU n EMRMEEEELLLLLILLLLULUOLIULCSLLLLEULLULCLLICTH
28. 0 of 93 Roads post 1 January 2000 current FC 3000 full specification of Roads Database tiles as 10 km by 10 km Feature Feature names Type code 3000 Motorway Line 3001 A Road Line 3002 B Road Line 3004 Minor Road Line 3500 Road Standard Node Font Symbol Motorway junction 3500 Road Standard Node Symbol Roundabout 3500 Road Standard Node Symbol Settlement 3500 Road Standard Node Font Symbol Link information 3501 Road Edge Node Font Symbol Administrative areas and Coastline Feature Feature names Type code 6401 County polygon Polygon 6403 District polygon Polygon 6403 District boundary line Line 6405 County District Line boundary line 6411 County seed Symbol 6415 District seed Symbol 6710 Boundary node Symbol unspecified 6711 Boundary edge node Symbol 6800 Admin area neat line Line 6200 Coast Line 6740 Coast node unspecified Symbol 6741 Coast edge node Symbol unspecified Developed land use area DLUA Feature Feature names Type code 6300 DLUA polygon Polygon 6310 DLUA seed point Symbol 6720 DLUA node unspecified Symbol 6721 DLUA edge node Symbol unspecified 6801 DLUA neat line Line Style Pen 3 2 5278719 Pen 2 2 16711680 Pen 2 2 16750640 Pen 1 2 8421504 Symbol 63 7381247 9 MapInfo Weather 16 0 Symbol 34 8421504 6 Symbol 32 16776960 5 Symbol 50 8421504 2 MapInfo Symbols 0 0 Symbol 51 8421504 5 MapInfo Symbols 0 0 Style Pen
29. 1 Ordnance Survey Top margin centrally aligned 1 500 ground metres Layer G8050571 Meridian 2 data Lower left margin 500 ground metres Layer G8050571 Translation date dd Mmmmmmmmm CCYY Lower left margin 500 ground metres Layer G8050571 Tile reference number Lower left margin 500 ground metres Layer G8050571 Reproduced from Ordnance Survey Meridian 2 data with the permission of The Controller of Her Majesty s Stationery Office Crown Copyright CCYY Lower right margin 500 ground metres Layer G8050571 The derived scale of the product is dependent upon the source data Lower right margin 500 ground metres Layer G8050571 The representation of a road track or path is no evidence of a right of way The alignment of tunnels is approximate Lower right margin 500 ground metres Layer G8050571 Date of last amendment dd Mmmmmmmmm CCYY Lower right margin 500 ground metres Layer G8050571 Product specification Meridian 02 04 Figure 5 1 Layout of footnotes srass 7 a l mmm mm mum mum l SSS 6 H le pun 5 1 1 11 Bm Meridian 2 technical specification chapter 5 v5 2 02 2007 Crown copyright Page 62 of 93 Chapter6 DXF file structure for Meridian 2 General The following paragraphs describe the DXF group and section structure fo
30. 10 000 1 10 000 1 10 000 1 50 000 1 250 000 1 250 000 1 250 000 1 50 000 Meridian 2 data is derived from the latest available versions of Ordnance Survey s databases The Meridian 2 dataset will be refreshed annually The large and small scale databases are controlled by the revision criteria for topography that are defined by Ordnance Survey for the various geographical areas Accuracy and resolution The resolution of the data supplied is 1 metre Meridian 2 data retains the same accuracy as the source data during its capture However it is not possible to calculate meaningful accuracy criteria for these data due to different source databases The Ordnance Survey Road Database has a 20 m filter applied to the centreline which is supplied to a 1 m resolution The 20 m filter does not affect the positional accuracy of node points During the updating of the road data there is a comparison buffer created around the existing road data to detect change This buffer is set to 3 m either side of a feature 5 m at each end and 10 of the length Administrative areas and roads data have a 20 m lateral filter applied to the boundary and centrelines The 20 m filter does not affect the positional accuracy of node points Features derived from the small scale databases have been subjected to generalisation information is cartographically represented in areas where accurate positional representation would cause confusing
31. 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template CC V i LAhuG nnd Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 41 of 93 Section Header Record SECHREC 07 Record 1 Field Position Format Value example Description REC_DESC 01 02 A2 07 SECT_REF 03 12 A10 10 km by 10 km tile reference for example TQ24 lt 6S gt COORD_TYP 13 13 I1 2 Rectangular STRUCT TYP 14 14 I1 1 Vector XYLEN 15 19 I5 00005 Five character coordinate fields to 1 m XY UNIT 20 20 I1 2 Metres XY MULT 21 30 R10 3 0000001000 Default ZLEN 31 35 I5 00000 Not used Z UNIT 36 36 I1 0 Not used Z MULT 37 46 R10 3 0000001000 Not used X ORIG 47 56 110 X coordinates of south west corner of unit Y_ORIG 57 66 110 Y coordinates of south west corner of unit Z DATUM 67 76 110 0000000000 Not used CONT_MARK 77 77 I1 1 Continuation record follows EOR 78 78 A1 96 Record terminator Record 2 Field Position Format Value example Description REC DESC 01 02 A2 00 XMIN 03 12 110 0000000000 YMIN 13 22 110 0000000000 XMAX 23 32 110 0000010000 YMAX 33 42 110 0000010000 XY_ACC 43 47 R5 2 00000 Not used Z_ACC 48 52 R5 2 00000 Not used SURV_DATE 53 60 DATE 00000000 Not used LAST_AMND 61 68 DATE yyyymmdd Date last amended COPYRIGHT 69 76 DATE yyyymmdd Copyright date CONT_MARK 77 77 I1 0 No further records EOR 78 78 A1 96 Record terminator R
32. 5678901234567890 Template i SSC Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 47 of 93 Attribute Record ATTREC 14 for cartographic name text Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 14 Feature code VAL_TYPE 15 16 A2 TX VALUE 17 A Text string DIVIDER EM A1 Divider CONT_MARK d I1 0 or 1 No further records or 1 or continuation record follows EOR Uu A1 96 Record terminator NOTE variable Record example 14000012FC6500TXANDOVERV0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template Attribute Record ATTREC 14 for railway links Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 14 Feature code VAL_TYPE 15 16 A2 RI VALUE 17 29 A13 Unique railway link identifier CONT_MARK 30 30 11 d No further records EOR 31 31 Al Record terminator Record example 14000002FC6140R141842002735110 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template RN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 48 of 93 Attribute Record ATTREC 14 for
33. Feature code AL TYPE 15 16 A2 LC VALUE 17 22 l6 Left county pointer to seed optional AL TYPE 23 24 A2 RC VALUE 25 30 l6 Right county pointer to seed optional VAL TYPE 31 32 A2 LD VALUE 33 38 l6 Left district pointer to seed optional AL TYPE 39 40 A2 RD VALUE 41 46 l6 Right district pointer to seed optional CONT MARK 47 47 I1 0 No further records EOR 48 48 A1 Record terminator Record example 14000014FC6405LC043050RC043084LD069234RD0697200 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template RN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 45 of 93 Attribute Record ATTREC 14 for administrative area points and or seeds Field Position Format Value example REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 VAL TYPE 09 10 A2 FC VALUE 11 14 l4 VAL TYPE 15 16 A2 PI VALUE 17 22 l6 VAL TYPE 23 24 A2 NM VALUE 25 A DIVIDER a A1 CONT_MARK 11 0 or 1 EOR d A1 96 NOTE variable integer Record example Description Unique attribute record identifier Feature code Unique global seed identifier Administrative area name Divider No further records or continuation record follows Record terminator 14000032FC6411PI043050NMHAMPSHIRE COUNTY 0 1 2 6 7 12345678901234567890123456789012345678901234567890123456789012345678901234567890 T
34. G8056255 G8056292 G8056552 G8056770 G8056771 G8056772 G8056773 G8056803 G8056664 G8056750 G8056663 G8056751 G8056802 G8056762 RN Meridian 2 technical specification chapter 5 v5 2 02 2007 Crown copyright Page 61 of 93 Feature name Dark link Canal Area water lake Area water seed Water text Water feature node Area water node Area water edge node Water feature edge node Area water neat line Woodland boundary Woodland boundary node Woodland seed Woodland tile edge node Woodland tile edge polygon Gridded height Line type CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS DOT DOT DOT DOT CONTINUOUS CONTINUOUS DOT CONTINUOUS DOT CONTINUOUS DOT Line Entity POLYLINE POLYLINE POLYLINE INSERT TEXT INSERT INSERT INSERT INSERT POLYLINE POLYLINE INSERT INSERT INSERT POLYLINE INSERT Colour BLUE YELLOW GREEN BLUE RED BLUE BLUE BLUE BLUE YELLOW CYAN BLUE WHITE WHITE CYAN MAGENTA Block SEEDPOINT CIRCLE CIRCLE CIRCLE CIRCLE CIRCLE SEEDPOINT CIRCLE DXF footnotes The following footnotes are added as an insert BLOCK in the ENTITIES section of the DXF data file The positions of the footnotes are indicated in figure 5 1 NOTE 1 NOTE 2 NOTE 3 NOTE 4 NOTE 5 NOTE 6 NOTE 7 NOTE 8 NOTE 9 Top margin centrally aligned 1 750 ground metres Layer G805057
35. GDTGGUDLLISS OA AwBAA aGBSOA j j jACS Meridian 2 technical specification chapter 1 v5 2 02 2007 Crown copyright Page 16 of 93 Figure 2 1 Link and node Points A and B are nodes as they intersect with other features The line A B is the link and in this example is made up of six individual line segments Polygons are continuous areas defined by sets of bounding closed lines These are implicit within the data but can be explicitly created with appropriate software Stored within recognisable polygons are seed points which hold information about that polygon for example a county name Figure 2 2 Polygon Point A is the polygon seed point for the area attached to this point are attributes such as the feature code which defines the polygon and its definitive name These attributes may be transferred to the polygon itself The polygon in this example comprises nine individual line segments There are also free standing points which are not associated with a defining polygon for example Liverpool Lime Street Station RN Meridian 2 technical specification chapter 1 v5 2 02 2007 Crown copyright Page 17 of 93 Chapter 2 Meridian explained Features Meridian 2 has two feature classes e Point features e Line features Point features such as administrative area seed points and line features such as roads railways and developed land use areas are arranged into recognisable categories A full listing of in
36. LAKES A FC6292 Area Water Seed Single FC6300 DLUA Boundary Single DLUA A FC6310 DLUA Seed Point Single FC6401 County Boundary Single ADMINLINE L COUNTY A FC6403 District Boundary Single ADMINLINE L DISTRICT A FC6405 County District Boundary Single ADMINLINE L FC6411 County Seed Point Single FC6415 District Seed Point Single FC6500 Names Unique CARTOTEXT T FC6551 Station Name Unique CARTOTEXT T FC6552 Water Text Unique CARTOTEXT T FC6663 Woodland Seed Single FC6664 Woodland Boundary Single WOODLAND A FC6710 Boundary Node Unspecified Single FC6711 Boundary Edge Node Single FC6720 DLUA Node Unspecified Single FC6721 DLUA Edge Node Unspecified Single FC6730 Railway Node Single FC6731 Railway Edge Node Single FC6740 Coast Node Unspecified Single FC6741 Coast Edge Node Unspecified Single FC6750 Woodland Node Single FC6751 Woodland Edge Node Single RN Meridian 2 technical specification chapter 8 v5 2 02 2007 Crown copyright Page 80 of 93 Feature code Description Symbol Legend FC6762 Height Point Feature Single HEIGHT P FC6770 Water Feature Node Single FC6771 Area Water Node Single FC6772 Area Water Edge Node Single FC6773 Water Feature Edge Node Single FC6800 Admin Area Neat Line Single FC6801 DLUA Neat Line Single FC6802 Woodland Neat Line Single FC6803 Area Water Neat Line Single RN Meridian 2 technical specification chapter 8 v5 2 02 2007 Crown copyright Page 81 of 93 An
37. N X GROUP Y GROUP Z GROUP Figure 6 15 Level 3 Kev o noy POLYLINE one or more ENTITY o optional VERTICES POLYLINE LAYER GROUP GROUP FOLLOW FLAG GROUP GROUP GROUP GROUP o o DEFAULT DEFAULT o SEQ END STARTING ENDING VERTICES GROUP WIDTH GROUP WIDTH GROUP o POLYLINE FLAG GROUP Figure 6 16 Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 75 of 93 Figure 6 16 Vertex entity level 4 Key one or more Figure 6 15 o optional VERTICES VERTEX LAYER o GROUP GROUP X GROUP Y GROUP Z GROUP o o j STARTING ENDING SCH VERTEX TANGENT GROUP WIDTH FLAGS Dese End of File group This group will end with DXF EOF End of File group o Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 76 of 93 Chapter 7 An overview of Meridian 2 in Mid Mif Meridian 2 is available in Mid Mif The transfer format is as defined by the MapInfo Professional User s Guide v8 0 MapInfo Map Interchange Format MapInfo Interchange Format MIF is an ASCII file format that can fully describe a MapInfo database Both graphic and tabular data are exported into MIF files The graphic data is in a file with a mif extension and the tabular data is in a file with a mid extension MapInfo Interchange Format files can be translated into other formats with other programs An overview of the data structure of a Meridian 2 file in Mi
38. NMNHMHE AA ARRKRK KEMEMNMNMNMNMMMKEENI Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 63 of 93 Header The header will be constructed as follows with only those fields being supplied Figure 6 2 Level 2 Key one or more o optional SECTION HEADER SECTION START o SECTION HEADER END SEC GROUP HEADER VARIABLE GROUP SEQUENCE The header must be structured in the following order 0 SECTION 2 HEADER 9 SACADVER 1 AC1009 9 SEXTMIN 10 nnnn 20 nnnn 9 nnn nnn SEXTMAX 10 nnnn 20 nnnnnmnn 9 nnn SLIMMIN 10 nn nn nn nn nnnnnn rn 20 nnnnnn rn 9 SLIMMAX 10 AutoCAD drawing database version number This indicates Release 11 or 12 not 9 X and Y drawing extents lower left corner Minimum eastings National Grid coordinates Minimum northings National Grid coordinates X and Y drawing extents upper right corner Maximum eastings National Grid coordinates Maximum northings National Grid coordinates X and Y drawing limits lower left corner X drawing limit lower left corner in the AutoCAD World Coordinate System WCS Y drawing limit lower left corner in WCS X and Y drawing limits upper right corner Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 64 of 93 nnnnnn n 20 nnnnnn n 9 SLTSCALE
39. O os goer Meridian 2 User guide and technical specification Meridian 2 User guide Contents Section Page no utn NN nme 3 Co ntact details 3 Eege UE 3 Purpose and disclaimer coo regen aaa a aaia aa E eaaa ANEA 3 ele TP 3 Data copyright and other intellectual property obt 4 le EE A Back up provision of the Droduct eene nene nnne 4 USING THIS gude er 4 Chapter 1 Jet Hd E 5 Meridian Z features nei leere ne eee I ge Ree LEHRER AERE A DA SR beaut lads EAR FRE eege ed eund 5 Applications of Ee EI 5 What you need to use Meridian 2 en Le elei La tet se avene drug nea 2a a DER ga a ER ZAR 6 Computer Nardware P 6 Computer S ftWale eege 6 Ri u M 6 Meridian 2 supply optlons reinen Ree en te de tana Laur pa aep Re Lee Rau EA TRA RA Ra 6 Meridian 2 supply formats ect gege e enhn nee aea e na suey eben n aae dg Na Ree ae le XR ES 7 Meridian 2 supply media tete ciet te cten adi apt ge e Mea AUN eR RR ARR ARN 7 Chapter 2 High level product overview eeeeeeeee eene eeeeee enne nnne nnne nnn nnnm antennes 8 leiere RO Rep 8 CUNT ONG 8 Accuracy e DEE 8 eil 8 Meridiam general Specifications oett dr eee re t d eee tet e E ea bea e d aidas 9 Chapter 3
40. Position Format Value example Description REC DESC 01 02 A2 00 FCNAME 03 22 A20 Meridian 02 00 6S Data specification product version FCDATE 23 30 DATE 20000901 Date of data specification DQNAME 31 50 A20 208 Not used DQDATE 51 58 DATE 00000000 Not used DATA MODEL 59 60 I2 00 CONT MARK 61 61 I1 0 No further records EOR 62 62 A1 96 Record terminator Record example 02Meridian02 01 DEFAULT 02 00 19920515 000000001 00Meridian_02 00 20000901 00000000000 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template Gridded height record example 02Meridian2 ht 01 99 DEFAULT 02 00 19920515 000000001 00Meridian_02 00 20000901 00000000000 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template RN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 40 of 93 Feature Classification Record FEATCLASS 05 Field Position Format Value example Description REC_DESC 01 02 A2 05 FEAT_CODE 03 06 14 Contains four character feature code CODE_COM 07 16 A10 lt 10S gt Not used STCLASS 17 36 A20 lt 20S gt Not used FEATDES 37 A Feature description DIVIDER SN A1 Divider CONT_MARK E I1 0 No further records EOR uu A1 96 Record terminator NOTE variable integer Record example 053000 Motorway 0 1 2 3 4
41. Railway edge node Type Line Line Line Line Point Point Type Line Line Point Point Point Code 3000 3001 3002 3004 3500 3501 Code 6140 6142 6155 6730 6731 Attribute s FC LL OD RN TR PN FC LL OD RN TR PN FC LL OD RN TR PN FC LL OD RN TR PN FC OD JN RT SN FC OD JN RT SN Attribute s FC RI FC RI FC SI PN FC FC RN Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 35 of 93 Administrative areas and coastline Feature description Type Code Attribute s County boundary Line 6401 FC LC RC LD RD District boundary Line 6403 FC LD RD County district boundary Line 6405 FC LC RC LD RD Neat line Line 6800 FC LC RC LD RD County seed Point 6411 FC Pl NM District seed Point 6415 FC Pl NM Boundary node Point 6710 FC Boundary edge node Point 6711 FC Coastline Line 6200 FC LC RC LD RD Coastline node Point 6740 FC Coastline edge node Point 6741 FC NOTE Includes London borough and unitary authority areas Developed land use areas DLUA Feature description Type Code Attribute s DLUA boundary Line 6300 FC DLUA seed Point 6310 FC PN DA DLUA node Point 6720 FC DLUA edge node Point 6721 FC Neat line Line 6801 FC Cartographic names Feature description Type Code Attribute s Place name Point 6500 FC TX Station name Point 6551 FC TX Hydrology Feature description Type Code Attribute s Water feature river
42. River small River medium River large River hidden Aqueduct Line type CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS DOT DOT CONTINUOUS DASHED DOT DOT DOT DASHDOT DASHED DASHDOT CONTINUOUS CONTINUOUS CONTINUOUS DOT DOT CONTINUOUS DOT DOT CONTINUOUS CONTINUOUS DOT DOT CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS CONTINUOUS DASHED CONTINUOUS Line Entity POLYLINE POLYLINE POLYLINE POLYLINE INSERT INSERT 3 POLYLINE POLYLINE INSERT INSERT INSERT 1 POLYLINE 1 POLYLINE ch W 1 POLYLINE 1 POLYLINE INSERT INSERT INSERT INSERT 1 POLYLINE INSERT INSERT 2 POLYLINE INSERT INSERT INSERT 1 POLYLINE TEXT TEXT 1 POLYLINE INSERT 1 LINE TEXT TEXT POLYLINE POLYLINE POLYLINE POLYLINE POLYLINE 32 0 Mi Colour BLUE RED ORANGE WHITE GREEN GREEN WHITE WHITE RED GREEN GREEN GREEN GREEN GREEN GREEN GREEN GREEN GREEN GREEN BLUE GREEN GREEN GREY GREY GREEN GREEN GREY WHITE WHITE WHITE WHITE WHITE WHITE YELLOW YELLOW GREEN GREEN GREEN Block CIRCLE small CIRCLE small CIRCLE CIRCLE small CIRCLE small SEEDPOINT SEEDPOINT CIRCLE CIRCLE CIRCLE CIRCLE DLUASEED CIRCLE CIRCLE ME_FOOTNOTES o Meridian 2 technical specification chapter 5 v5 2 02 2007 Crown copyright Page 60 of 93 Layer name G8056232 G8056243
43. The National GIU eee EE 10 Annexe A Product and service performance report form eere 11 v5 2 02 2007 RN Meridian 2 user guide contents v5 2 02 2007 Crown copyright Page 2 of 93 User guide Preface This user guide hereafter referred to as the guide is designed to provide an overview of Meridian 2 hereafter referred to as the product If you find an error or omission in this guide or otherwise wish to make a comment or suggestion as to how we can improve the guide please contact us at the address shown below under contact details or complete the product and service performance report form at annexe A and return it to us Contact details Our Customer Service Centre will be pleased to deal with your enquiries Customer Service Centre Ordnance Survey Romsey Road SOUTHAMPTON S016 4GU Business enquiries 44 0 23 8030 5030 General enquiries calls charged at local rate 08456 05 05 05 Dedicated Welsh Language HelpLine 08456 05 05 04 Textphone deaf and hard of hearing users only please 44 0 23 8079 2906 Email customerservices ordnancesurvey co uk or visit the Ordnance Survey website at www ordnancesurvey co uk Use of the product The terms and conditions upon which the product including this guide is made available to you and your organisation are contained in the customer contract made between you and Ordnance Survey If there is an inconsistency between the terms of yo
44. The direction is from the end of the feature to the last minus one pair of coordinates Attribute codes Attribute codes provide supplementary information on a feature providing such qualifying information as feature code feature name orientation and so on In NTF the structure of user defined attributes is described in the Attribute Description Record ATTDESC The actual attribute detail of a record is written in the Attribute Record ATTREC RN Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 33 of 93 Attributes that are used in the supply of Meridian 2 data are FC Feature code contains the numeric feature code of the feature OD OSODR a unique identifier for links and nodes on road features LL Length of link RN Road number DfT route number TR Trunk road indicator RT Roundabout indicator JN Junction name the name of a road junction LC Left county boundary indicator RC Right county boundary indicator LD Left district boundary indicator RD Right district boundary indicator PI Global ID a unique identifier for administrative areas DA DLUA ID a unique identifier for a developed land use area PN Proper name the definitive name for a developed land use area or railway station RI Rail ID a unique railway link identifier SN Settlement name text SI Station ID a unique railway station identifier NM Admin name an administrative area name T
45. X Text independent text FA Forest ID a unique identifier for forest areas WA Water area a unique identifier for water area WI Water link a unique identifier for water links HT Height ID a unique identifier for gridded height Includes London borough and unitary authority area Unique identifiers Unique identifiers are used to uniquely identify some features within Meridian 2 These are Ordnance Survey Roads Database Reference OSODR this uniquely identifies any road link or road node within the national Roads database Railway and railway station identifiers these uniquely identify any railway link or railway station within the national Meridian 2 database Developed land use area identifier this uniquely identifies any developed land use area seed point within the national Meridian 2 database Global identifier this uniquely identifies any administrative area seed point within the 10 km by 10 km tile Water identifier this uniquely identifies the hydrology inland water seed Woodland identifier this uniquely identifies the woodland seed The unique identifiers are unique references and are maintained except where there has been significant change to a feature The unique identifier may refer to several links representing a linear object across tiles for example a road or a railway which may be chained together across tile edges Thus on adjoining tiles there may be two or
46. XTPOS TEXT REPRESENTATION RECORD TEXTREP GEOMETRY RECORD GEOMETRY ATTRIBUTE RECORD ATTREC Records Text details are only given when a name has been cartographically positioned The Attribute Record ATTREC contains the definitive name and is pointed to by the Text Record TEXTREC The Text Record TEXTREC points to the Attribute Record ATTREC and also points to the Text Position Record TEXTPOS The Text Position Record TEXTPOS refers back to the Text Record TEXTREC and points to the Geometry Record GEOMETRY 1 containing the coordinates of the digitised position The Text Position Record TEXTPOS also points to the Text Representation Record TEXTREP which contains the standard digitising position and orientation of the text All other names are held as attributes only Node detail Node feature Each node feature is depicted by the use of the following records Description in NTF NODE RECORD NODEREC NODE CONTINUATION RECORD GEOMETRY RECORD GEOMETRY 1 POINT RECORD POINTREC ATTRIBUTE RECORD ATTREC All links in Meridian 2 terminate in explicit node records each node is related to a point and its attributes via a common geometry record This structure allows an attribute with a node within the constraints of NTF Records Node Record NODEREC transfers details of the bearings and number of lines that meet at a point or node The Node Record NODEREC contains refere
47. apefile format defines the geometry and attributes of geographically referenced features in as many as five files with specific file extensions that should be stored in the same project workspace They are shp the file that stores the feature geometry shx the file that stores the index of the feature geometry dbf the dBASE file that stores the attribute information of features When a shapefile is added as a theme to a view this file is displayed as a feature table sbn and sbx the files that store the spatial index of the features These two files may not exist until you perform theme on theme selection spatial join or create an index on a theme s shape field If you have write access to the source data directory the index files will be persistent and remain after your ArcView session is complete If you do not have write access to the source data directory they will be removed when you close the project or exit ArcView ain and aih the files that store the attribute index of the active fields in a table or a theme s attribute table These two files may not exist until you perform link on the tables If you have write access to the source data directory the index files will be persistent and remain after your ArcView session is complete If you do not have write access to the source data directory they will be removed when you close the project or exit ArcView The native shapefile format used by ArcView GIS does n
48. appropriate unique identifier when the database is refreshed The unique identifier for a feature will never be modified only created and or deleted If a feature is deleted from the Meridian 2 database then the unique identifier allocated to that feature will cease to exist RN Meridian 2 technical specification chapter 2 v5 2 02 2007 Crown copyright Page 23 of 93 Feature layer descriptions The feature codes that appear in Meridian 2 within each layer are detailed in chapter 6 of the technical specification The individual layers are described below NOTE Names or numbers appear in all layers as attributes The roads layer is the first hierarchical layer the other layers will be manipulated to fit in the following 1 8 hierarchical order 1 Roads Motorways major and minor roads are represented in the data Complex junctions are collapsed to single nodes and multi carriageways to single links To avoid congestion some minor roads and cul de sacs less than 200 m are not represented in the minor road feature description of the data Private roads and tracks are not included Hierarchical position 1 2 Railways All railway stations open to passengers and single track passenger lines are represented A railway intersection consists of links and a node but where railways cross at different levels links are not broken Links and nodes carry a feature code If the station name differs from the name of the built up area on Or
49. at NTF A format designed in 1988 specifically for the transfer of spatial information it is published as British Standard BS 7567 and is administered by the British Standards Institution It is now the standard transfer format for Ordnance Survey digital map data node An object representation of a point that either does not form any part of a link isolated node or polygon seed point or is the representation of a point at the start or end of a link terminating node The position of a node is defined by a single coordinate pair which is repeated within all links logically connected at that node and or containing it A node is only deleted if the link containing it as a terminating node is deleted northings See rectangular coordinates orientation Orientation of a point or a text feature is measured in degrees anticlockwise from grid east origin The zero point in a system of rectangular coordinates packing Spaces used as fillers to complete a record or field pecked line A line drawn as a series of dashes physical record A physical record may be fixed length containing 80 characters or variable length containing up to 80 characters point A zero dimensional spatial abstraction of an object represented as a coordinate pair point and line data A form of vector data designed for map production in which all map features are designated as points lines or text Point and line data does not carry the topological relations
50. be a single coordinate pair for a single point feature for a railway station or two or more coordinate pairs for a linear feature Each feature is classified by means of a feature code Roads railways railway stations administrative area seed points DLUA seed points inland water and woodland area seed points have unique identifiers Meridian 2 vector data structure Meridian 2 data within each layer is supplied as vector data in a link and node structure Geographical features are represented as data entities either as points or lines Points are fixed positionally by one coordinate pair for example a railway station Lines are fixed positionally by a series of connected coordinate points to represent linear map features such as roads railways and so on Points and lines within the data model determine the geometric positional characteristics of the data Points and lines within the data model also have associated attributes These give the point and line entities meaning that is they represent the descriptive characteristic of an entity such as a feature code a name or numerical value Lines are also added as closing links neat lines along tile edges these are required to complete the enclosure of an area The closing link has a different feature code to the other links enclosing the area Throughout Meridian 2 no line feature crosses from one tile to the next but a point feature created at the tile edge has the same coordinate
51. cal format for storing the geometric location and attribute information of geographic features A shapefile is one of the spatial data formats that you can work with in ArcView GIS source scale The scale of the source information from which the map was digitised that is the scale of survey for a basic scale map or the scale of the source map for a derived map spatial data Data that includes a reference to a two or three dimensional position in space as one of its attributes It is used as a synonym for geometric data structured data Data within which collections of features of any type form objects Topographically structured data also contains topological information defining the relationships between features and objects terminator A character character string field or record used to signal the end of a record section volume or database RN Meridian 2 technical specification annexe A v5 2 02 2007 Crown copyright Page 88 of 93 text coordinates Each text feature has a start of text coordinate that is digitised text feature A free standing text string in the digital data describing a feature or particular instance of a feature for example Factory or Acacia Avenue text height The height at which a text string is intended to be plotted out at the nominal map scale This information is included in the feature header of the text feature text position See text coordinates Also known as original digitising posi
52. ciceaeuc esae rco rin e etue tectae co kac aan nc clue oce b ac aka soa dac coude enun nd caRone pana 18 lg julrcfc4q e aA 18 POINTS ANG P M A 18 lp ua MelecienREpe m 20 Feature attribute data eee tete Seed EA deed EELER 20 Feature codes 2 P Vo 20 Names as le 21 Road number RN attribute dne iaidd eter etae pec eapi ER enda d eiia 21 Trunk road TR attribute vx 2 2 ec E tbe d dei dcs bed e bad a aiaa aeaiia 21 Line Te VEER E dl TE 21 OSODR RENE Geen EN nis ESI vetoes 22 Proper name PN attribute t teet Pride e Pride nho bee Fa Etna ada ea EA 22 Roundabout RT attribute a enano addaa eei p De Fab pne abe onde 22 Junction name JN attribute etre te tc bert ed e dade adds 22 Settlement name SN attrib te enr d c t e a e tee Een anaes 23 Unique identifiers esses nnnm eren nne n enne EEEn nns nn nnne rens 23 Feature layer description 24 Alizf rtr eT 27 An overview of Meridian 2mNTE eene ren nennen nemen 27 Jackson structure nennen ener eren ene n hn nennr trs n nnne nennen tren nsn nnn 28 Transfer set structure 29 ize P nm 29 Record terminator EOR nennen enne enne nnn ens 29 Supply of data on formatted meda eene 29 Versi
53. clutter on the viewed image To maintain positional relationships such data has been further adjusted to fit the hierarchy where necessary Completeness During production many checks are undertaken to ensure that data supplied to customers are both accurate and complete During digital manipulation in creating the upgraded data all sources of that data are checked against specification documentation to identify whether any features have been omitted or misaligned RN Meridian 2 user guide chapter 2 v5 2 02 2007 Crown copyright Page 8 of 93 These quality control checks take the form of e visual checks by operators e independent quality assurance checks and e computer validation with the specification Meridian general specifications The following gives details of the product specification identity and its relationship to Ordnance Survey data capture specifications Version details of these specifications are also stated Product Product specification Meridian 2 Meridian_02 00 Transfer format specifications Name NTF BS 7567 DXF Release 12 Shape MID MIF Level 3 Version 2 1 Issue date 15 May 1992 1 January 1997 RN Meridian 2 user guide chapter 2 v5 2 02 2007 Crown copyright Page 9 of 93 Chapter3 The National Grid Meridian 2 tiles are identified by quoting the National Grid reference of the south west corner of the area they cover The Ordnance Survey National Grid divides Great Britain into squares 100 km
54. cord example 15000027004804010048040 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template RN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 51 of 93 Node Record NODEREC 16 Field Position Format Value example Description REC_DESC 01 02 A2 16 NODE ID 03 08 l6 Unique node record identifier GEOM ID 09 14 l6 Pointer to GEOMETRY 1 record of point feature NUM LINKS 15 18 l4 20 DIR Ka I1 10r2 1 for start of link or 2 for end of link GEOM ID RS le Pointer to GEOMETRY 1 of link ORIENT nt R4 1 Bearing of first last segment of link clockwise from grid north not used for roads LEVEL zT I1 0 or 1 Link level at node roads only 1 Link level at node for all other layers CONT MARK s I1 0 No further records or 1 or continuation record follows EOR a A1 Record terminator NOTE variable integer Record example 1600000800480400012004921226000 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template NOTES indicates repeating group The pair of fields VAL TYPE and VALUE will repeat to specify all the attributes required It may be necessary to utilise a continuation record to specify all attributes RN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 52 of 93 Two di
55. d Mif is shown below Files below supplied on CD The files below are created for each layer as they are imported into MapInfo Once this is done it s ready for use the above example is for the A road layer Structure of Meridian 2 in MapInfo Meridian 2 has a limited link and node data structure within this structure a feature may be a name a point or a line or series of lines forming a coherent unit Each feature is free standing that is its topological relationship to any other feature is not expressed in the data Features are classified by type and each type is placed in a separate TAB layer NOTE Road change information only consists of tabular data that is it will not have any geographic map data Line features A feature is a subjective entity that is so long as the constituent lines are the same description layer a feature need not fully describe a logical piece of detail The extent of a feature is determined by digitising conventions and does not always coincide with the topology Each linear feature is composed of a string of XY coordinate pairs implicitly joined by straight lines The line weights for the layers are defined by the parameter file shown in annexe B Area features Area features are polygons with attributes added Names features Names features are treated as free standing text data There is no explicit relationship in the data between a text feature and the point or line fea
56. d area contains a seed point identifier which carries a feature code and the associated attribute To maintain positional relationship features in this layer may be adjusted and fitted to hierarchy Hierarchical position 7 8 Gridded height Height information is produced in the form of digital terrain model DTM style data Gridded height information is averaged from the 50 m resolution Land Form PANORAMA dataset to a resolution of 200 m and rounded down to the nearest 1 m value NOTE Gridded height is supplied with Meridian 2 on a separate CD 00 Meridian 2 technical specification chapter 2 v5 2 02 2007 Crown copyright Page 26 of 93 Chapter3 NTF explained An overview of Meridian 2 in NTF This chapter gives a detailed breakdown of the data structure of Meridian 2 in NTF Meridian 2 data is supplied in the British Standard national format common to all Ordnance Survey s digital map data products namely NTF and is transferred in Level 3 as variable length records An overview of the data structure of a Meridian 2 data file is on the following page The convention used for this diagram is in the industry standard adopted for Jackson Structured Programming JSP The British Standard for NTF stipulates the following for Level 3 This level supports a variety of data models that may include network data polygons semantic relationships and complex features for example a school consisting of its build
57. d captured from the map base In this way an A road is distinguished from a B road and other kinds of line feature by the feature code allocated to it BS 7567 Each feature is classified as belonging to a specific feature code These feature N T F codes are listed in chapter 3 C Meridian 2 technical specification chapter 2 v5 2 02 2007 Crown copyright Page 20 of 93 Each feature is classified as belonging to a specific feature layer These layers D X F range in value from G8050570 to G8056801 see the AutoCAD publication Layer Naming Convention for CAD in the Construction Industry version 2 based upon guidelines in BS 1192 Part 5 Guide for structuring of computer graphic information These feature layers are listed in chapter 5 Attributes are stored as extended entity data An additional text feature code for layout of footnotes is included This feature code is listed in chapter 5 These differences in the data are inferred during translation from Ordnance Survey s internal data format to the required customer transfer format Names as attributes The criteria for names attribute attachment are e Admin name NM is an attribute of a seed point in its administrative area for example Hampshire County e Proper name PN is an attribute of a seed point in a DLUA for example Bexhill or a node point for a railway station for example Great Ayton Station e Text TX is a text string transfer
58. dividual features is given in chapter 3 of the technical specification Each feature has two components e Feature position e Feature attributes data Also explained in this chapter e Feature layer descriptions Each feature recorded in Meridian 2 should be considered as a DXF entity Line D X IF features are recorded as DXF line s or polyline s Point features will be recorded in the data as INSERT BLOCKS Certain standard symbols are defined in the BLOCKS section of the data file A list of these standard symbols is shown in chapter 5 Attributes are stored as extended entity data Points and lines Real world geographic features are represented in the digital map data as structures of lines and points Each point or line has a geometric and attribute component The geometric component defines the positional characteristic of the feature and implicit relationships exist between points and lines based on relative position The attribute component defines the descriptive characteristics of the feature Points may exist independently of lines A diagrammatic example of a geometric structure is shown in figure 2 1a Figure 2 1a A geometric structure of points and lines Solid black grey and broken grey lines and associated points are on different layers Tile Y d Edge D L Points e Lines Points and lines from the geometric structure become features when an attribute the feature c
59. dnance Survey s large scale data for example New Street Station in Birmingham or if the railway station name is not associated to any built up area name for example Great Ayton Station then the points will carry a railway station name Node attributes will also be shown as cartographic station names To maintain positional relationship features in this layer may be adjusted and fitted to the roads Hierarchical position 2 3 Administrative areas and coastline Administrative areas include information for unitary authority areas for Scotland Wales county district and London borough boundaries for England Figure 2 4 Hierarchical relationship of boundaries for England Line A is a county and district or London borough boundary Line B is a district or London borough boundary N Sec B Each link for an administrative area carries a feature code and the administrative level associated with the left and right sides of that link This also applies to coastline but only to the landside of the coastline that is no administrative area information is added to the seaward side Each administrative area contains a seed point that identifies the enclosed area and carries a feature code and the associated administrative area name Separate areas of the same administrative unit carry seed points with different identifiers Offshore islands carry a county and district or unitary authority seed point There is no
60. e greater explanation where necessary e Provide Licensed Partners with as much detail as necessary to enable Meridian 2 files in DXF to be easily understood and processed by application software The term data structure used in these chapters refers to the organisation and sequence of the records in the data file and not to the geographical topology of the data These chapters should be read in conjunction with chapter 1 and chapter 2 which describe the content of Meridian 2 An overview of Meridian 2 in DXF DXF Meridian 2 is available in DXF conforming to AutoCAD release 12 using extended entity data to store attributes The transfer format is that defined by the NEDO Working Party for the exchange of two dimensional drawings in the construction industry An overview of the data structure of a Meridian 2 file in DXF is shown below Key one or more o optional DXF FILE ENTITIES END OF FILE HEADER TABLES BLOCKS SECTION GROUP SECTION SECTION SECTION Structure of Meridian 2 in DXF Meridian 2 has a limited link and node data structure within this structure a feature may be a name a point or a line or series of lines forming a coherent unit Each feature is free standing that is its topological relationship to any other feature is not expressed in the data Features are classified by type and each type is placed in a separate DXF layer Line features A feature is a subjective entity that is so lon
61. e names can have more than one in them When using more than one you must remember to type in the file extension in order to save the file correctly For example you can name a table as follows spam for lunch today and every day dbf Layer names were created and set when the original NTF data was translated number of layers 20 The Meridian import parameters in the translator highlights a feature code and allocates it to a layer The logic behind which layer the feature code was allocated to was down to relationship of features Neatline No neatline Grid No grid Grid values No grid values Important information Certain feature codes that are used and defined in NTF are not required or used in MapInfo Some examples of this are e 3501 Road Edge Node e 6411 County Seed e 6710 Boundary Node unspecified Other feature codes that are not used 6415 6711 6800 6741 6310 6720 6721 6801 6731 6730 6292 6770 6771 6772 6773 6803 6663 6802 6750 6751 and 6740 See annexe B for more detail of feature codes RN Meridian 2 technical specification chapter 7 v5 2 02 2007 Crown copyright Page 78 of 93 Chapter8 An overview of Meridian 2 in ESRI shapefile ESRI shapefiles are a simple non topological format for storing the geometric location and attribute information of geographic features A shapefile is one of the spatial data formats that you can work with in ArcView GIS The sh
62. e source and history of the geometric data within the map and the coordinate system in use as well as holding information essential to the management of Ordnance Survey s digital mapping system map scale The ratio between the extent of a feature on the map and its extent on the ground normally expressed as a representative fraction for example 1 1250 or 1 50 000 megabyte Mb 1 048 576 bytes a measure of data storage capacity Mid Mif definition MID is a MapInfo database and Mif is a MapInfo Interchange which is an ASCII file format and is used for export Tabular data is held in a file with a mid extension and graphic data is held in a file with a mif extension Mif files can be translated into other formats and used with other programmes o Meridian 2 technical specification annexe A v5 2 02 2007 Crown copyright Page 86 of 93 name or text feature The proper name or label of an object real world or feature object abstraction consisting of one or more text strings A name position is defined by a coordinate pair National Grid A unique referencing system that can be applied to all Ordnance Survey maps of Great Britain GB at all scales It is based on 100 km squares covering the whole of GB based on a Transverse Mercator projection It is used by Ordnance Survey on all post war mapping to provide an unambiguous spatial reference in GB for any place or entity whatever the map scale National Transfer Form
63. ecord DBHREC e Feature Classification Record FEATCLASS e Attribute Description Record ATTDESC e Section Header Record SECHREC e Section body see Point and line features e name detail e node detail e Volume Terminator Record VOLTERM Section body This comprises all the features within the tile that correspond to the feature types selected by the customer Point and line features Point feature Each point feature is depicted by the use of the following records Description in NTF POINT RECORD POINTREC GEOMETRY RECORD GEOMETRY 1 ATTRIBUTE RECORD ATTREC Line feature Each line feature is depicted by the use of the following records Description in NTF LINE RECORD LINEREC GEOMETRY RECORD GEOMETRY1 GEOMETRY CONTINUATION RECORDS ATTRIBUTE RECORDS ATTREC Geometry records Geometry records contain the coordinate position s in metres of the feature Point features contain one coordinate pair line features contain two or more coordinate pairs Geometry Continuation Records are used where required X COORDS Y COORDS and QPLAN are treated as separate fields RN Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 31 of 93 Name detail Each cartographically positioned name is depicted by the use of the following records Description in NTF TEXT RECORD TEXTREC TEXT POSITION RECORD TE
64. ecord example 21000052000000100000000000000010000000520000000014000000000000001 00000000000000000000000000010000000001000000000000000000000020011210200112100 07TQ24 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template NOTE 1 Last amend date will not be used for Mer_2_rds RN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 42 of 93 Attribute Record ATTREC 14 for road links Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique ID for record VAL TYPE 09 10 A2 OD VALUE 11 23 A13 Unique ID OSODR for link VAL TYPE 24 25 A2 FC VALUE 26 29 14 Feature code VAL_TYPE 30 31 A2 LL VALUE 32 33 I5 Length of link VAL TYPE vt A2 PN VALUE Ka A Road name DIVIDER T A1 VAL_TYPE a A2 RN VALUE AS A Road number DIVIDER ex A1 VAL_TYPE E A2 TR VALUE A1 Y Trunk road indicator CONT MARK s I1 0 No further records or 1 Continuation record EOR A1 96 Record terminator NOTE variable integer Record example 140000010D033 8UHKOPLWAXFC3001LL00342PNCOMMERCIAL STREET NP02P001J945LPCABAXPO1 0001CB3HJ50VFWARNA315 T TRY0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template NOTE 1 PN RN and TR records will only be included where a name exists o 0 0
65. emplate Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 46 of 93 Attribute Record ATTREC 14 for nodes administrative areas DLUA coastline and railway hydrology and woodlands and or edge nodes all layers Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 14 Feature code CONT_MARK 15 15 I1 0 No further records EOR 16 16 A1 96 Record terminator Attribute Record ATTREC 14 for DLUA links Field Position Format Value example Description REC DESC 01 02 A2 14 ATT ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 14 Feature code CONT_MARK 15 15 11 d No further records EOR 16 16 Al Record terminator Attribute Record ATTREC 14 for DLUA points and or seeds Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 l4 Feature code VAL TYPE 15 16 A2 DA VALUE 17 29 A13 Unique DLUA seed identifier VAL TYPE 30 31 A2 PN VALUE 32 A DLUA name DIVIDER SEN A1 Divider CONT_MARK T I1 0 No further records or 1 or continuation record follows EOR SES A1 96 Record terminator NOTE variable Record example 14000032FC6310DA4418200463301PNGrafton 0 1 2 3 4 5 6 7 8 1234567890123456789012345678901234567890123456789012345678901234
66. eset intervals of either distance or time as the cursor is traced along a map feature distinctive name A text feature consisting of text string s that form s a proper name DXF Data Exchange Format A proprietary data format devised by Autodesk by which digital drawings may be transferred between users of CAD systems DXF has become an industry standard data format and is used for the transfer of some Ordnance Survey data products eastings See rectangular coordinates edge match The process of ensuring that data along the adjacent edges of map sheets or some other unit of storage matches in both positional and attributes terms entity Something about which data is stored in a databank or database For example building or tree The data may consist of relationships attributes positional and shape information and so on Often synonymous with feature Extended Binary Coded Decimal Interchange Code EBCDIC An eight bit character encoding scheme S Meridian 2 technical specification annexe A v5 2 02 2007 Crown copyright Page 84 of 93 Extent of the realm EOR The external bounding lines of Land Line data is EOR The Territorial Waters Jurisdiction Act 1878 and the Territorial Waters Order in Council 1964 confirm that EOR of Great Britain as used by Ordnance Survey is properly shown to the limit of mean low water mean low water springs in Scotland for the time being except where extended by Parliament feature
67. esty s Stationery Office who has delegated powers to the Director General Ordnance Survey for the administration of copyright in publications and data including the determination of terms and conditions under which permission for their reproduction is given currency An expression of the up to dateness of data data A representation of facts concepts or instructions in a formalised manner suitable for communication interpretation or processing data capture The encoding of data In the context of digital mapping this includes map digitising direct recording by electronic survey instruments and the encoding of text and attributes by whatever means data format A specification that defines the order in which data is stored or a description of the way data is held in a file or record data model An abstraction of the real world that incorporates only those properties thought to be relevant to the application or applications at hand The data model would normally define specific groups of entities and their attributes and the relationship between these entities A data model is independent of a computer system and its associated data structures A map is one example of an analogue data model RN Meridian 2 technical specification annexe A v5 2 02 2007 Crown copyright Page 83 of 93 database An organised integrated collection of data stored so as to be capable of use in relevant applications with the data being accessed by d
68. f record terminator is the percent 96 ASCII 37 character for both formatted and unformatted media A transfer set normally equates to a single file except where continuation volumes are used when the transfer set exceeds the capacity of the media The data the customer receives is in one or more transfer sets Each transfer set starts with a Volume Header Record VOLHDREC and terminates with a Volume Terminator Record VOLTERM Supply of data on formatted media Data requested on CD is not blocked but is written directly to the output device The transfer set has one dataset and one section One or more transfer sets are put onto the medium A customer s order that is larger than the capacity of the medium is put onto two or more of that media Continuation volumes are only to be used if a transfer set is larger than the capacity of the medium Formatted media transfer set less than media capacity 01 Volume header record 01 02 Database header record 40 Attribute description record 05 Feature classification record 07 Section header record Tile 1 data 99 Volume termination record 01 Volume header record 01 02 Database header record 40 Attribute description record 05 Feature classification record 07 Section header record Tile 2 data 99 Volume termination record And so on Tile n data 99 Volume termination record Q9end of transfer set 0 o MENENENENMHMNH
69. g as the constituent lines are of the same description layer a feature need not fully describe a logical piece of detail The extent of a feature is determined by digitising conventions and does not always coincide with the topology Each linear feature is composed of a string of XY coordinate pairs implicitly joined by straight lines The colour and line weights of some layers may differ when DXF is used with certain software packages Area features Area features are not defined within vector link and node data Features that might be thought of as area features are treated in the data as linear features for example a DLUA boundary is treated as a polyline in layer G8056300 RN Meridian 2 technical specification chapter 5 v5 2 02 2007 Crown copyright Page 58 of 93 Name features Name features are treated as free standing text data There is no explicit relationship in the data between a text feature and the point or line feature to which it belongs Ordnance Survey distinguishes between layer name types for example place names and station names by placing each name type in a separate DXF layer Text has position expressed as a single coordinate pair held as X and Y offsets from the map origin south west corner Text that is double or treble banked is treated as two or three separate features The text string may be considered to be contained within an envelope whose bottom left hand corner is positioned on this coo
70. has a value of 2 e Align Y group 21 only present if Justify type group is present and has a value of 2 f EXTENDED entities these consist of e Application name 1001 e Control string 1002 e String 1000 one or more e Control string 1002 0 0 0 MENENENENMEERZAZEEEEEMKN M K NNNN NNI Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 73 of 93 Figure 6 11 Level 2 Key o one or more ENTITIES o optional SECTION ENTITIES SECTION ENTITIES EXTENDED GROUP GROUP ENTITIES Figure 6 12 Level 3 SECTION START ENDSEC GROUP Key one or more LINE o optional ENTITY LINE START X START Y GROUP GROUP GROUP S END X 1 START Z GER EXTENDED GROUP ENTITIES Figure 6 13 Level 3 Key one or more INSERT o optional ENTITY INSERT LAYER X Y Z S GROUP GROUP GROUP GROUP GROUP ROTATION P X SCALE Y SCALE Z SCALE ANGLE EXTENDED FACTOR FACTOR FACTOR GROUP GROUP GROUP GROUP ENTITIES RN Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 74 of 93 Figure 6 14 Level 3 Key one or more TEXT o optional ENTITY TEXT LAYER x Y o 9 GROUP GROUP GROUP GROUP GROUP o o ROTATION RELATIVE OBLIQUE X SCALE ANGLE FACTOR ANGLE GROUP GROUP GROUP o o o TEXT TEXT HORIZONTAL VERTICAL STYLE NAME GENERATION JUSTIFICATION JUSTIFICATION GROUP FLAGS TYPE TYPE ALIGN ALIGN ALIG
71. hips between features point feature A zero dimensional spatial abstraction of an object with its position defined by a coordinate tuple Points are represented by nodes which may be isolated or part of a link terminating Points may also be represented by symbols that may have attributes such as rotation and size polygon Polygons are a representation of areas A polygon is defined as a closed line or perimeter completely enclosing a contiguous space and made up of one or more links At least one node occurs on the perimeter of a polygon where the bounding link completes the enclosure of the area There may be many nodes connecting the bounding links of a polygon Links may be shared between polygons Polygons may wholly contain other polygons or be contained within other polygons Each may contain a single isolated node seed point that identifies the polygon polygon boundary The link or links that enclose a polygon projected into the horizontal plane o Meridian 2 technical specification annexe A v5 2 02 2007 Crown copyright Page 87 of 93 polygon point See seed point positional accuracy The degree to which the coordinates define a point s true position in the world directly related to the spheroid projection on which the coordinate system is based precision The exactness with which a value is expressed whether the value be right or wrong record A set of related data fields grouped for processing recording f
72. hnical specification chapter 4 v5 2 02 2007 Crown copyright Page 54 of 93 Text Record TEXTREC 43 Field Position Format Value example Description REC_DESC 01 02 A2 43 TEXT_ID 03 08 l6 Unique text record identifier NUM SEL 09 10 12 01 SELECT 11 12 A2 00 TEXT_CODE 13 16 A4 0000 TEXP_ID 17 22 l6 Pointer to TEXTPOS record NUM ATT 23 24 12 01 ATT_ID 25 30 l6 Pointer to ATTREC record CONT MARK 31 31 I1 0 No further records EOR 32 32 A1 96 Record terminator Record example 4300000701000000000007010002670 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template Text Position Record TEXTPOS 44 Field Position Format Value example Description REC_DESC 01 02 A2 44 TEXP_ID 03 08 l6 Unique text position record identifier cross reference from TEXTREC NUM TEXR 09 10 I2 01 TEXR ID 11 16 l6 Pointer to TEXTREP record GEOM ID 17 22 l6 Pointer to GEOMETRY 1 record CONT MARK 23 23 I1 0 No further records EOR 24 24 A1 Record terminator Record example 44000007010000070002670 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template 0 0 0 MENENENNENMEEkEERIYRESEANMNMENENNNENNEEENENNNEEENI Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 55 of 93 Text Representation Record TEXTREP 45
73. ifferent logical paths Theoretically it is application independent but in reality it is rarely so dataset An Ordnance Survey term for a named collection of logically related features arranged in a prescribed manner For example all water features A dataset has more internal structure than a layer and is related to another dataset only by position DDS Digital Data Storage density A measure of the number of units of data held on a stated length of storage surface detached part A term applying to a part of a local government or parliamentary area that is completely surrounded by other local government or parliamentary areas and is not connected to the parent area by direct access on the ground digital Data that is expressed as numbers digits in computer readable form is said to be digital digital map Any map sold by Ordnance Survey or its agents in any form that is on computer readable media or as hard copy on paper and or film or microfilm produced mainly or wholly using computerised means digital map data The digital data required to represent a map The data includes not only map detail but also feature header data map header data and management data digitising The process of converting analogue maps and other sources to a computer readable form This may be point digitising where points are only recorded when a button is pressed on a cursor or stream digitising where points are recorded automatically at pr
74. ings boundaries and playing fields This level is designed for e Transferring basic geometry and simple features through the use of geometry and feature records e Relating basic geometrical and topological elements to one or more features through the use of chain polygon and complex line records e Combining features to form complex features through the use of collection and complex polygon records e Using text records both to relate text strings to features and cartographic output e Referencing and positioning external features for example raster data The record structure at this level may also be defined to be compatible with data in Levels 1 and 2 There are certain conventions used in this technical specification which are Square brackets are placed around record names for example VOLHDREC A pair of braces denote field names for example REC_DESC is the Record Descriptor field 90 A two digit number following square brackets denotes the record descriptor that uniquely identifies the record name between the brackets S This is the space character ASCII code 32 3S This denotes three successive space characters The percentage character ASCII code 37 This denotes a repeating group ASCII code 124 RN Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 27 of 93 Jackson structure The following diagrams are examples of Meridian 2 files and no fixed record
75. l i EE e Names are normally placed on the printed map parallel to the horizontal grid Position 0 is supplied N T F relationship of the text to its coordinate pair is expressed as an original digitised position Where the position of text features is recorded one of these positions is digitised Hierarchical position 5 The text string may start end or be centred on this coordinate pair the Meridian 2 technical specification chapter 2 v5 2 02 2007 Crown copyright Page 25 of 93 6 Hydrology Each water area contains a seed point identifier that carries a feature code and the associated attribute Each link for water boundaries carries a feature code To maintain positional relationship features in this layer may be adjusted and fitted to the hierarchy See the note at the beginning of feature layer descriptions earlier in this chapter Dark links have been used to maintain the connectivity of the network across lakes and reservoirs Where links entering and leaving the lake or reservoir carry the same name the dark link is attributed with this name Hierarchical position 6 Figure 2 6 Dark link diagram showing connectivity A Dark link A river and tributaries flow into a lake The amalgamation of these is a dark link running through the middle of the lake and outputting as a river again 7 Woodlands Each link for woodland boundaries carries a feature code Each woodlan
76. le road centrelines that may or may not represent a real world feature link Links are the representation of line features They are made up of one or more consecutive non intersecting link segments with common attributes between two terminating nodes Links have no connection with other links except at the start or end via common shared terminating nodes points All links contain their terminating coordinates Links may form the boundaries of polygons and may be shared between polygons See also line link and node data A form of vector data in which linear features are represented as links Links are terminated where they intersect other links These intersection points and link ends may carry nodes whose feature records express the geometric relationships between links link and node structure A data structure in which links and nodes are stored with cross referencing map The representation on a flat surface of all or part of the Earth s surface intended to be communicated for a purpose or purposes transforming relevant geographic data into an end product that is visual digital or tactile map generalisation A reduction in map detail so that the information remains clear and uncluttered when map scale is reduced May also involve re sampling to larger spacing and or a reduction in the number of points in a line map header Data at the start of the digital map file describing that data It may contain information on th
77. ll the attributes required It may be necessary to utilise a continuation record to specify all attributes RN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 53 of 93 Line Feature Record LINEREC 23 Field Position Format Value example Description REC_DESC 01 02 A2 23 LINE_ID 03 08 l6 Unique line record identifier GEOM ID 09 14 l6 Pointer to GEOMETRY 1 record NUM ATT 15 16 12 01 ATT_ID 17 22 l6 Pointer to ATTREC record CONT MARK 23 23 I1 0 No further records EOR 24 24 A1 96 Record terminator Record example 23004804005369010053690 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template Attribute Description Record ATTDESC 40 Field Position Format Value example Description REC_DESC 01 02 A2 40 VAL_TYPE 03 04 A2 Attribute mnemonic FWIDTH 05 07 A3 001 999 If fixed or 3S or if variable FINTER 08 12 A5 format desc If fixed or A or if variable ATTNAME 13 A Attribute name See below DIVIDER KC A1 Y Divider FDESC ks A Attribute See below description DIVIDER s A1 Divider CONT_MARK I1 0 No further records NOTE variable integer Record example for a variable record 40JN A JUNCTION NAMENName Of Road Junction 0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template 0 Meridian 2 tec
78. logical connection in the data between them and administrative units other than the same name attribute There is no explicit information to identify which links form the bounds of a particular area The left and right county and district pointers on links do not contain the name of the administrative area but refer to the seed point that has the administrative area name as its attribute The coastline follows the mean high water MHW up all estuaries to the normal tidal limit NTL Administrative areas are only shown down to MHW The administrative areas are adjusted to the coastline To maintain positional relationship features in this layer may be adjusted and fitted to roads and railways Hierarchical position 3 RN Meridian 2 technical specification chapter 2 v5 2 02 2007 Crown copyright Page 24 of 93 4 Developed land use areas Developed land use area DLUAs features represent the polygons around cities towns villages and industrial commercial and business parks as contained within the Strategi dataset Link features enclose DLUA features Such areas contain a seed point that identifies the enclosed area and carry a feature code and the associated DLUA name There is no explicit information to identify which link forms the bounds of a particular area The whole DLUA has been positioned to the road pattern by best fit practice Hierarchical position 5 5 Cartographic names Place names from the small scale database and
79. mbol 34 16711680 9 Symbol 34 16711680 9 Symbol 34 16711680 9 Style Font Times New Roman Font Arial Names Style Pen 1 2 4243711 Pen 2 2 4243711 Pen 3 2 4243711 Pen 1 3 4243711 Pen 1 193 4243711 Pen 1 3 32896 Pen 1 2 65535 Pen 1 2 65535 Brush 2 11593215 16777215 Symbol 49 4227327 12 Symbol 49 4227327 12 Symbol 49 4227327 12 Symbol 49 4227327 12 Symbol 49 4227327 12 Pen 1 2 255 Font Times New Roman RN Meridian 2 technical specification annexe B v5 2 02 2007 Crown copyright Page 92 of 93 Woodlands Feature Feature names Type Style code 6664 Woodland polygon Polygon Pen 1 1 32896 Brush 2 11599792 16777215 6663 Woodland seed Symbol Symbol 49 0 12 6802 Woodland neat line Line Pen 1 2 32896 6750 Woodland node Symbol Symbol 49 0 12 6751 Woodland edge node Symbol Symbol 49 0 12 Height Feature Feature names Type Style code 6762 Height Point feature Font Symbol Symbol 35 12632256 2 MapInfo Symbols 0 0 Roads prior to 1 January 2000 FC 6000 stripped Roads Database tiles as 20 km by 20 km Feature Feature names Type Style code 6001 Motorway Meridian 1 Line Pen 2 2 5278719 6041 A Road Meridian 1 Line Pen 2 2 16711680 6061 B Road Meridian 1 Line Pen 2 2 16744448 6080 Minor Road Meridian 1 Line Pen 1 2 8421504 RN Meridian 2 technical specification annexe B v5 2 02 2007 Crown copyright Page 93 of
80. mensional Geometry Record GEOMETRY 1 21 associated with POINTREC Field Position Format Value example Description REC_DESC 01 02 A2 21 GEOM_ID 03 08 l6 Unique geometry record identifier GTYPE 09 09 I1 1 Point feature NUM COORD 10 13 l4 0001 Point has one coordinate pair X COORD 14 18 I5 X coordinate Y COORD 19 23 I5 Y coordinate QPLAN 24 24 A1 lt S gt Not used CONT_MARK 25 25 I1 0 No further records EOR 26 26 A1 96 Record terminator Record example 21000031100011564044030 0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template Two dimensional Geometry Record GEOMETRY 1 21 associated with LINEREC Field Position Format Value example Description REC_DESC 01 02 A2 21 GEOM_ID 03 08 l6 Unique geometry record identifier GTYPE 09 09 I1 2 Line feature NUM COORD 10 13 l4 Number of coordinate pairs in range 0002 9999 X COORD 14 18 I5 X coordinate Repeated until NUM COORD has been transferred Y COORD 19 23 I5 Y coordinate Repeated until NUM COORD has been transferred QPLAN 24 24 A1 lt S gt Not used CONT_MARK m 11 0 No further records or 1 or continuation record follows EOR ed A1 96 Record terminator NOTES variable integer This record may contain many CONTINUATION 00 records indicates a repeating group The pair of fields VAL TYPE and VALUE will repeat to specify a
81. nces to each Line Record LINEREC that meets at that node and to the Geometry Record GEOMETRY 1 The Geometry Record GEOMETRY 1 is referenced by the Point Records POINTREC containing the feature attributes of the node Where lines do not meet at a previously specified point feature a special point feature is created The Node Record NODEREC can contain details of up to five line features that meet at a node Further lines meeting at that node are written to the Node Continuation Record It is important to note that although the Node Record contains references to its appropriate point and line features the point and line features do not contain references to the node RN Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 32 of 93 Feature information relevant to NTF Point features Point features can exist independently and at the junction or ends of lines The point feature gives a position and attribute to the corresponding node Line features All line features with the exception of where railways cross at different levels are broken when they intersect one another within a layer NOTE A layer is a subset of digital map data selected on a basis other than position For example one layer might consist of all features relating to roads and another to railways The first and last coordinate pairs in a line correspond exactly with the start or end coordinates of any adjoining line s A
82. nexe A Glossary accuracy The closeness of the results of observations computations or estimates to the true values or the values accepted as being true Accuracy relates to the exactness of the result and is the exactness of the operation by which the result is obtained administrative area A blanket term used by Ordnance Survey to refer to all public administrative areas specifically local government management and electoral areas American Standard Code for Information Interchange ASCII A seven bit code for encoding a standard character set area A spatial extent defined by circumscribing lines that form a closed perimeter that does not intersect itself area seed A point within an area that can be used to carry the attributes of the whole area for example ownership address and use type attribute An attribute is a property of an entity usually used to refer to a non spatial qualification of a spatially referenced entity For example a descriptive code indicating what an entity represents or how it should be portrayed attribute class A specific group of attributes for example those describing measure serviceability structure or composition attribute code An alphanumeric identifier for an attribute type attribute value A specific quality or quantity assigned to an attribute basic scale The scale at which the survey is maintained For Ordnance Survey mapping three scales 1 1250 1 2500 and 1 10 000 are u
83. nses e poster distribution e TV and or radio advertising regions and e product and or brand promotion campaigns e Financial Insurance e customer bases and e high low risk areas RN Meridian 2 user guide chapter 1 v5 2 02 2007 Crown copyright Page 5 of 93 e Health e community health and e health black spots e Leisure activities e large site planning for example golf courses e tourism and e theme park locations What you need to use Meridian 2 Computer hardware This product may be used on a wide range of hardware platforms provided sufficient memory and storage facilities are available varying from desktop PCs using GIS or CAD to mainframe computers with specialised translators and applications Computer software Meridian 2 is supplied as inert data and does not include software for data manipulation To exploit fully the potential of Meridian 2 it is necessary to use appropriate application software such as GIS or CAD BS 7567 NTF allows users of GIS to customise their own definition of the data and or plotting for their specific applications The parameters defining colours line styles text styles symbols and so on should be built into user software Meridian 2 may be customised by viewing or plotting features in different colours line styles and scales to suit different applications Certain classes of features may be omitted from customised plans on the basis of selection by feature code
84. nsists of tabular data that is it will not have any geographic map data Important information Certain feature codes that are used and defined in NTF are not required or used in ESRI shapefiles Some examples of this are e 3501 Road Edge Node e 6411 County Seed e 6710 Boundary Node unspecified Other feature codes that are not used 6415 6711 6800 6741 6300 6310 6720 6721 6801 6731 6730 6255 6292 6770 6771 6772 6773 6803 6664 6663 6802 6750 6751 and 6740 RN Meridian 2 technical specification chapter 8 v5 2 02 2007 Crown copyright Page 79 of 93 Symbology table Feature code Description Symbol Legend FC3000 Motorway Single MOTORWAY L FC3001 A Road Single AROAD L FC3002 B Road Single BROAD L FC3004 Minor Road Single MINORROAD L FC3500 Road Node Unspecified Single ROADNODE P JUNCTION P ROUNDABOUT P SETTLEMENT P FC3501 Road Edge Node Unspecified Single FC6140 Railway Single RAILWAYLINE L FC6142 Railway Tunnelled Single RAILWAYLINE L FC6155 Station Point Single RAILWAYSTN P FC6200 Coast Single COASTLINE L FC6223 Water Feature River Small Single RIVER L FC6224 Water Feature River Medium Single RIVER L FC6225 Water Feature River Large Single RIVER L FC6230 Water Feature Hidden Single RIVER L FC6231 Water Feature Aqueduct Single RIVER L FC6232 Water Feature Dark Link Single RIVER L FC6243 Water Feature Canal Single RIVER L FC6255 Area Water Lake Single
85. o dimensional Geometry Record GEOMETRY 1 21 associated with POINTREC 53 Two dimensional Geometry Record GEOMETRY 1 21 associated with LINEREC 53 Line Feature Record LINEREC 23 54 Attribute Description Record ATTDESC 40 54 Text Record TEXTREG 43 4 ied ceder ie cine tite ENEE E d e re dde Ie edad 55 Text Position Record TEXTPOS A4 55 Text Representation Record TEXTREP Ab 56 Comment Record COMMENT OU 56 Volume Terminator Record VOLTERM OO 57 pigebit 58 An overview of Meridian 2 in DStE nennen mener n enhn nenernerrnnn ns 58 DO EE 58 Structure of Meridian 2 In DXF EE 58 Fine Teatules uere e reo ERR en RR TREE ERU DR eessen EE Lo VER VAT EMEN ES 58 Area features 58 Name features H 59 Drawing content and format 59 Coordinate system 59 LGU Lu 59 Layer ANIM OS D ua cides ded ceca EEEE EEEE EREA E terraced 59 Mtv e EE 59 nM MU 59 SIG VAIS Sh M M 59 Meridian 2 DXF layers ssssssssssseeenenenn een meeen nn NEEE EEEE Ea 60 DXF fOOtNOtES D pC 62 DXF file structure for Meridian 2 1 ceci eec ice mei coros NENNEN ee 63 crure 63 Datei SUCtU es PEE P 63 elle TEE 64 EISE 66 Eeler 71 Entities SOCOM TT 72 Eog o
86. ode has been added for example DLUA seed points are created from points or DLUA boundaries from lines C o NENNEN Meridian 2 technical specification chapter 2 v5 2 02 2007 Crown copyright Page 18 of 93 Figure 2 1b The same geometric structure as features Solid black greys and broken grey are on different layers In figure 2 1b Point A is a seed point with a feature code that Edge identifies it as a DLUA the seed point also carries its name attribute Bryncethin Point B is a coordinate junction between intersecting features in this case where a minor road intersects with the A406 This is an example of a node Point C is a position where the A406 in one layer crosses the DLUA boundary in another layer There is no node at this point Some points and lines are common to more than one feature as in figure 2 1b Features between D E and Nodes e 6 Links mm G B F are overlapping features and are stored separately within each layer of data Seed points O Separate storage of overlapping features Figure 2 1c Roads Figure 2 1d DLUA Tile id ST68 Tile id ST88 LINE ID 41 E D LINE ID 71 Tile LINE ID 62 LINE ID 130 Edge OSODR OMJ945LPCABAX Tile id ST86 Nodes Seed point Links In figures 2 1c and 2 1d line D E is common to the minor road and the DLUA boundary and the geometry of each featu
87. on management 30 Ie E 31 SOCON DOV M TEE 31 Point and line features ciiasan indiana aaia aaa aaa aaa aaia 31 Name TC 32 N d detail 32 Feature information relevant to NTF scceceeeeeeeeeeaeeeeeeeeeeeeceeaaeceeesesesecaeaeeeeeeeeeetenseaees 33 POINT CG EE 33 BI 33 eeler 33 Ti CET 33 Attribute CodeS P aaia 33 Unique Identifiers cene ood en crine d e ea eon nen deed eege 34 Mem 35 Feature large Ee e 35 FROGS EE 35 KEIER 35 Administrative areas and coastline ccccececeeeceeceeeeeeeeecaeeeceeeeesececaaecaeceeeeeeesecsncaeeeeees 36 Developed land use areas ODUUA enne 36 Meridian 2 technical specification contents v5 2 02 2007 Crown copyright Page 12 of 93 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Cartographic names essences ee seeeeeeeseaeeeeeseeeeeeseeeeeeeseeeeeeeseeeaeeesenaees 36 FLY tee KT 36 VWoodlande cece 37 ele ue 37 Record structures for the transfer of Meridian 2 in NTF s ccsscssseeeeseeeesseeeeseeeenseeeees 38 NTF Record List 38 Volume Header Record VOLHDREC OT 39 Database Header Record DBHREC ON 40 Feature Classification Record FEATCLASS 05 sse 41 Section Header Record SECHREC 07 sss eene 42 Attribute Record ATTREC
88. or to 1 January 2000 FC 6000 stripped Roads Database tiles as 20 km by P un TEE 93 v5 2 02 2007 Meridian 2 technical specification contents v5 2 02 2007 Crown copyright Page 14 of 93 Introduction Purpose of this specification and disclaimer This is the technical specification hereafter referred to as the specification referred to in the Framework Direct Licence Specific Use Framework Partner Licence or your other customer contract We may change the information in this specification at any time giving you the notice period specified in the customer contract made between you and Ordnance Survey We do not accept responsibility for the content of any third party websites referenced or accessed in or through this specification any other contractual documentation and or the Ordnance Survey website Copyright This specification including for the avoidance of doubt any mapping images reproduced herein is Crown copyright 2007 All rights reserved Any part of this specification may be copied for use internally in your organisation or business so that you can use Meridian 2 for the purpose for which it is licensed to your organisation or business but not otherwise No part of this specification may be reproduced or transmitted in any form or by any means including electronically for commercial exploitation without the prior written consent of Ordnance Survey No part of this specification may be copied or incorpora
89. ord terminator NOTE variable integer Record example 14000032FC6411PI043050NMHAMPSHIRE COUNTY V0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template 0 00 NMENENENENENENMNPNEEEEEEEEENEEEEEEEEEEEEEEEEEEEEEEEEEEEN Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 50 of 93 Attribute Record ATTREC 14 for gridded height point Field REC_DESC ATT_ID VAL_TYPE VALUE VAL_TYPE VALUE CONT_MARK EOR Position 01 02 03 08 09 10 11 14 15 16 17 24 25 25 26 26 Format A2 l6 A2 l4 A2 l8 I1 A1 Value example 14 FC HT or 1 96 Description Unique attribute record identifier Feature code Height attribute No further records or continuation record follows Record terminator NOTE variable integer Record example 14000090FC6762HT000000070 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template Point Feature Record POINTREC 15 Field Position Format Value example Description REC_DESC 01 02 A2 15 POINT_ID 03 08 l6 Unique point record identifier GEOM ID 09 14 l6 Pointer to GEOMETRY 1 record NUM ATT 15 16 12 01 ATT_ID 17 22 l6 Pointer to ATTREC record CONT MARK 23 23 I1 0 No further records EOR 24 24 A1 96 Record terminator Re
90. ormat The logical and or physical levels of the protocol governing the laying down of data on the physical transfer medium rectangular coordinates Also known as X Y coordinates and as eastings and northings These are two dimensional coordinates that measure the position of any point relative to an arbitrary origin on a plane surface for example a map projection a digitising table or a VDU screen resolution A measure of the ability to detect quantities High resolution implies a high degree of discrimination but has no implication as to accuracy For example in a collection of data in which the coordinates are rounded to the nearest metre resolution will be 1 m but the accuracy may be 5 m or worse section In NTF terminology a subdivision of a database In Ordnance Survey terms this equates to a single map sheet that is a digital map file or a tile seed A seed is a digitised point within an area usually a defined polygon for example a lake or woodland but not always for example a geographical seed such as the South Downs seed point A coordinated point an isolated node within an area usually a defined polygon to which alphanumeric information may be attached as an attribute for example a name or a feature code Also known as a polygon seed area seed or representative point segment A chord defined by two consecutive coordinates in a line string shapefile or shp SRI shapefiles are a simple non topologi
91. ot support text thus any text files converted into shapefile format will become a coverage of points In order to display cartographic text in ArcView including orientated text it is necessary to translate the data into Arcinfo Interchange Format E00 and then use the Import 71 utility supplied with ArcView to convert the text data into an Arc coverage ArcView will display shapefiles and Arc coverages with a random point line region text style each time they are opened ArcView legend files can therefore be created to enable the data to be displayed with the same symbology whenever it is displayed When using a legend file it is possible to display the features in a theme based on one of the theme s attributes this essentially creates a thematic or unique values map In a unique values map a different colour is used to symbolise each value in an attribute In the case of Meridian 2 the cartographic text theme uses a unique values legend to distinguish place names station names and water text All other themes use single symbol legends that is all features in the theme will be displayed using the same symbology In order for the legend files to work they must have the same file name as the one to which they correspond for example motorways shp must have a legend file called motorways avl Structure as MID MIF see chapter 7 Drawing content and format as MID MIF also see chapter 7 NOTE Hoad change information only co
92. pe Table e Layer Table e Style Table Figure 6 4 Linetype Table Level 3 Key e one or more LINETYPE o optional TABLE ENDTAB LINETYPE GROUP DEFINITIONS Figure 6 5 LINETYPE GROUP The Linetype Table will contain definitions for the following line types solid line CONTINUOUS dashed line DASHED dashdot line DASHDOT dotted line DOT Figure 6 5 Level 4 Key one or more LINETYPE o optional DEFINITIONS LTYPE LINETYPE STANDARD LINETYPE GROUP NAME FLAGS DESCRIPTION GROUP GROUP GROUP ALIGNMENT NUMBER OF TOTAL o CODE DASH ITEMS PATTERN DASH LENGTH GROUP GROUP LENGTH GROUP GROUP Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 67 of 93 Thus TABLE LTYPE 70 LTYPE 2 CONTINUOUS 70 64 3 Solid Line 72 65 73 0 40 0 0 0 LTYPE 2 DASHED 70 64 3 72 65 73 40 0 75 49 0 5 49 0 25 LTYPE 2 DASHDOT 70 0 RN Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 68 of 93 72 65 73 40 1 0 49 0 5 49 0 25 49 0 0 49 0 25 LTYPE DOT 0 25 49 0 0 49 0 25 0 ENDTAB RN Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 69 of 93 Figure 6 6 Level 3 Key one or more o optional ENDTAB Se GROUP DEFINTIONS ENDTAB GROUP ITEM TYPE COLOUR LINETYPE GROUP GROUP GROUP De
93. ple is fictional and does not relate to River Lydden o Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 49 of 93 Attribute Record ATTREC 14 for water area seeds Field Position Format Value example Description REC_DESC 01 02 A2 14 ATT_ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 l4 Feature code VAL TYPE 15 16 A2 WA VALUE 17 29 A13 Unique water area seed identifier VAL TYPE 30 31 A2 PN VALUE 32 A Water area name where applicable DIVIDER SM A1 Divider CONT_MARK Eis I1 0 No further records or 1 or continuation record follows EOR Kg A1 Record terminator NOTE variable integer Record example 14000032FC6292WA0060273530510PNULLSWATER 0 1 2 3 4 5 6 7 8 12345678901234567890123456789012345678901234567890123456789012345678901234567890 Template NOTE The WA identifier in the record example is fictional and does not relate to Ullswater Attribute Record ATTREC 14 for administrative area points and or seeds Field Position Format Value example Description REC DESC 01 02 A2 14 ATT ID 03 08 l6 Unique attribute record identifier VAL TYPE 09 10 A2 FC VALUE 11 14 14 Feature code VAL_TYPE 15 16 A2 PI VALUE 17 22 l6 Unique global seed identifier VAL TYPE 23 24 A2 NM VALUE 25 A Admin area name DIVIDER m A1 Divider CONT_MARK a I1 0 No further records or 1 or continuation record follows EOR bul A1 96 Rec
94. r the transfer of Meridian 2 It is assumed that the reader of this chapter is familiar with the AutoCAD release 12 reference manual which is published by Autodesk Ltd 1 Meadow Gate Avenue Farnborough Business Park FARNBOROUGH GU14 6FG Website www autodesk co uk or an equivalent document published by the reader s software supplier if a CAD package other than AutoCAD is to be used Meridian 2 DXF files containing Ordnance Survey data can be very large and so are supplied on CD ROM media only This chapter gives a detailed breakdown of the data structure of Meridian 2 in DXF This is a two stage procedure that consists of e a diagrammatic view of the data structure with a preceding outline description of that part of the data structure and e detailed examples of the record sequence and contents of the data structure A diagram of the record group precedes each example Data structure The following diagrams figures 6 1 6 14 represent the data structure of DXF Where one element of a figure is the starting point for another figure this is indicated beneath the relevant box For details of the specification for the DXF group see the AutoCAD Release 12 reference manual Figure 6 1 Level 1 Key one or more o optional DXF FILE o o o HEADER TABLES BLOCKS SECTION SECTION SECTION ENTITIES SECTION Figure 6 2 Figure 6 3 Figure 6 9 Figure 6 11 C NENNENENE
95. rEle GOUD rises EEE EE B ee tp sacnteaedeecententen 76 An overview of Meridian 2 in Mid Mif ccssseceessseeeensseeeeeenseeceeseseeeeeenseseenenseecenees 77 Meridian 2 is available in MdiMn eene 77 Meridian 2 technical specification contents v5 2 02 2007 Crown copyright Page 13 of 93 Chapter 8 Annexe A Annexe B Structure of Meridian 2 in Mapinfo nennen nnne 7T Line features R 77 DICCERCCUU CC RR 77 Names features 77 Drawing content and format 78 Coordinate system 78 BE E EE 78 Layer EIER E 78 KE ul 78 GAG EE 78 Grid KETTEN 78 Important InfOFTmatiOn accion aaa aaa aa a aa aaa aa anti aa E aaa 78 An overview of Meridian 2 in ESRI shapefile eese 79 Important informatio BEEN 79 Neier Karl EEN 80 COLLIER T T 82 Meridian 2 MapInfo Mid Mif layers eeeeeeeeeeeereneeen nennen ennt nnn 90 IMPOKANTMTONIMALUOM Pm 90 Roads post 1 January 2000 current FC 3000 full specification of Roads Database tiles as 10 ouam 91 Administrative areas and Coastline sss 91 Developed land use area DLUA ener teens 91 RalWAYyS m M 92 Cartographic NAMES TI E 92 ere te e e KEE 92 Heel TEE 93 alle 93 Roads pri
96. rdinate pair Text is oriented that is it may run from west to east across the map or it may be plotted at some other angle measured anticlockwise from grid east Drawing content and format Coordinate system The coordinate system is National Grid NG The National Grid coordinates are to a resolution of 0 01 m This is the resolution of the source data Height No height attributes are applied to any feature See chapter 2 of the technical specification 8 Gridded height Layer names See the AutoCAD publication Layer Naming Convention for CAD in the Construction Industry version 2 which is based upon the guidelines laid down in BS 1192 Part 5 Guide for structuring of computer graphic information Each layer name is an eight character string The first four characters relate to the AUG Autodesk system with G GIS as the source of the information and 800 899 as the part code This product is G805 The remaining four digits relate to existing Ordnance Survey digital map data in their own NTF system and are leading zero filled For example G8053000 Motorways Neatline Neatlines around the extent of the map data are added as lines in the ENTITIES section layer name G8050572 Grid A grid is added as lines in the ENTITIES section layer name G8050572 The grid is created by the translator and therefore must be specified before the translation takes place Grid values Full 100 000 metre National Grid ea
97. re is stored separately RN Meridian 2 technical specification chapter 2 v5 2 02 2007 Crown copyright Page 19 of 93 Figure 2 1e Administrative areas and coastline Tile Edge Nodes e Seed point Links In figures 2 1c and 2 1e line G B F is common to the A406 the minor road and administrative area boundary and the geometry of each feature is stored separately Feature position The geometry of map features is defined in terms of coordinates All coordinates used in Meridian 2 are based on the National Grid coordinate referencing system and are quoted to a resolution of 1 m The National Grid as it applies to Meridian 2 is explained more fully in chapter 3 of the user guide Feature attribute data An attribute is the descriptive characteristic of a feature that is a non spatial element The geometry of the points and lines within the data would be meaningless to the user unless they are assigned some distinguishing property In Ordnance Survey map data terms an attribute can be a feature code in NTF these are numeric codes for example 3000 or a distinctive name or number for example Birmingham or M40 Attribute codes relevant to NTF are listed and described within chapter 3 of the technical specification but an overview is given below Feature codes Each feature is classified by means of a feature code FC A feature code is allocated when each feature is initially interpreted an
98. read many device The digital bits are encoded into a vegetable dye and once written cannot be erased by overwriting with subsequent data A laser reads the disc continuation mark A logical record may contain more data than can be held in a single physical record The physical record contains a continuation mark the penultimate character of the record in NTF to indicate whether more data is to be found in a continuation record continuation record A specific NTF term A continuation record is used where space does not allow one logical record to be contained wholly within one physical record coordinate pair A coordinate pair is an easting and a northing coordinates Pairs of numbers expressing horizontal distances along original axis Alternatively that triplets of numbers measuring horizontal and vertical distances Row and column numbers of pixels from raw imagery are not considered coordinates for the purpose of the standard copyright Copyright is a legal property right that enables the creator of an original work to protect it from unauthorised use Through the Copyright Designs and Patents Act 1988 Crown copyright continues to subsist in all Ordnance Survey products until the end of the period of 50 years from the end of the year in which they were published and in the case of data from the end of the year in which it was extracted from the Ordnance Survey database Crown copyright is vested in The Controller of Her Maj
99. red in an attribute record to be displayed as stand alone cartographic text for example Southampton a place name e Hydrology WA is an attribute of a seed point in a water area e Woodlands FA are an attribute of a seed point in a woodland area Road number RN attribute This attribute defines the DfT road classification number for example M40 that relates to a link If a road is not classified then this attribute will not be present Trunk road TR attribute This attribute defines whether the link forms part of a trunk road If it is then the link will have a trunk road attribute with a value of Y if itis not a trunk road then there will be no value in this field Line length LL attribute This attribute defines the length of the link in metres and will be present for all link records It is calculated from the planimetric coordinates making up the link and does not take into account the effect of slope The link length in all products refers to the length as recorded in the Roads database OSODR attribute This attribute defines the Ordnance Survey Roads Database Reference OSODR This will uniquely identify any link or node within the national Roads dataset The OSODR will be used as the unique identifier for each link and node rather than the NTF identifiers The NTF identifiers will be unique within each tile that is supplied but will not be maintained between supplies A road object is part of a road be
100. ry users can group like features for search display and output routines e Meridian 2 is defined as a limited link and node structure within each layer It contains points lines and nodes Nodes have pointers to lines that join at the node and similarly there are lines that enclose an area containing a point Some points are not contained within areas enclosed by lines e Department for Transport DfT road classification numbers are stored in attribute records and are applied to features such as roads Names applying to administrative areas and developed land use areas are also included in the attribute record of the appropriate point feature e Annual updating of many of the source databases ensures that high standards of currency and integrity are maintained The road network in Meridian 2 is a derived and simplified network that has been produced from Ordnance Survey Roads Database Applications of Meridian 2 There are many potential applications for Meridian 2 These include e Environmental analysis e Flood areas analysis e Land management e Commercial and or business site development e Retail and or wholesale trades e Distribution networks e store and or warehouse locations and e strategic business expansion and or development e Marketing and media planning e sales force locations and or territories e sales prospecting e market analysis of customers competitors or outlet densities e market analysis of direct mail respo
101. s guide any contractual documentation and or the Ordnance Survey website Copyright This guide including for the avoidance of doubt any mapping images reproduced herein is Crown copyright 2007 All rights reserved CO o NENNEN Meridian 2 user guide preface v5 2 02 2007 Crown copyright Page 3 of 93 Any part of this guide may be copied for use internally in your organisation or business so that you can use the product for the purpose for which it is licensed to your organisation or business but not otherwise No part of this guide may be reproduced or transmitted in any form or by any means including electronically for commercial exploitation without the prior written consent of Ordnance Survey No part of this guide may be copied or incorporated in products services or publications that you generate for onward sale or as free promotional or support materials without the prior written consent of Ordnance Survey Data copyright and other intellectual property rights The Crown or where applicable Ordnance Survey s suppliers owns the intellectual property rights in Ordnance Survey digital map data Full details of the terms and conditions under which Ordnance Survey digital map data may be processed and or manipulated or copied by a customer whether or not for use on PCs or workstations or for making hard copies are available from the Customer Service Centre please see Contact details
102. se 12 with extended entity data e Mid Mif MapInfo e Shapefile ESRI Meridian 2 supply media Data is supplied on CD ROM for all of the above formats Data supply structures MID MIF Root directory _Doc _Disccare txt _Meridian2006 _readme txt _Data _Data files NTF and DXF Root directory _Doc _Disccare txt _Meridian2006 _readme txt _Data _100k Folder structure for example TQ _Data files SHAPE Root directory Doc Disccare txt Meridian2006 readme txt Data cartotext info Data files The year changes to reflect the year of release RN Meridian 2 user guide chapter 1 v5 2 02 2007 Crown copyright Page 7 of 93 Chapter 2 Source of Meridian 2 High level product overview Meridian 2 data are derived from large scale and small scale digital databases The data capture source and scales are Feature Road network Railways County district and London borough for England Unitary authority areas for Wales Unitary authority areas for Scotland Coastline Developed land use areas and place names Hydrology Woodlands Gridded height Currency Original data source Roads centrelines Ordnance Survey Roads Database Large scale database Boundary Line Boundary Line Boundary Line Landranger Strategi Strategi Strategi Land Form PANORAMA Source scales 1 1250 1 2500 and 1 10 000 1 1250 1 2500 and 1 10 000 1
103. sed Any area is only maintained at one basic scale block Data on magnetic media may be recorded in blocks of characters for more efficient movement within or between computer systems The length of the block will vary according to the medium and the data transfer format used boundary A boundary is the limit of a predefined and established area whose limit is determined by one or more lines for example county area boundary and DLUA boundary byte A unit of computer storage of binary data usually comprising 8 bits equivalent to a character Hence megabyte Mb and gigabyte Gb CAD Computer aided design cartography The organisation and communication of geographically related information in either graphic or digital form It can include all stages from data acquisition to presentation and use character A distinctive mark an inscribed letter one of a set of writing symbols RN Meridian 2 technical specification annexe A v5 2 02 2007 Crown copyright Page 82 of 93 character string A one dimensional array of characters held either in memory or in another storage medium coding Allocation of a feature code to a feature being created from constituent construction data points and or segments with optional linking to an existing feature of the same feature code compact disc read only memory CD ROM A data storage medium A 12 cm disc similar to an audio CD Ordnance Survey uses the writable CD a WORM write once
104. small Line 6223 FC WI PN Water feature river medium Line 6224 FC WI PN Water feature river large Line 6225 FC WI PN Water feature hidden water Line 6230 FC WI PN Water feature aqueduct Line 6231 FC WI PN Water feature dark link Line 6232 FC WI PN Water feature canal Line 6243 FC WI PN Water feature lake Line 6255 FC WI Area water seed Point 6292 FC WA Water text Point 6552 FC TX Water feature node Point 6770 FC Area water node Point 6771 FC Area water edge node Point 6772 FC Water feature edge node Point 6773 FC Area water neat line Line 6803 FC C Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 36 of 93 Woodlands Feature description Type Code Attribute s Woodland boundary Line 6664 FC Woodland seed Point 6663 FC FA Woodland node Point 6750 FC Woodland edge node Point 6751 FC Woodland neat line Line 6802 FC Height Feature description Type Code Attribute s Gridded height Point 6762 FC HT RN Meridian 2 technical specification chapter 3 v5 2 02 2007 Crown copyright Page 37 of 93 Chapter 4 Record structures for the transfer of Meridian 2 in NTF NTF Record List This list comprises the valid record types used in the Meridian 2 NTF transfer set Descriptor 01 02 05 07 14 15 16 21 23 40 43 44 45 90 99 Description Volume Header Record defines the donor and data type Database Header Record transfers data about the da
105. sting and northing values followed by an m are added as text strings in the ENTITIES section layer name G8050573 at each corner of the map extent either horizontal or vertical to read from the lower left corner of the tile Intermediate grid values are shown as multiples of 1 000 metres from the nearest 100 km National Grid layer name G8050572 These are horizontal RN Meridian 2 technical specification chapter 5 v5 2 02 2007 Crown copyright Page 59 of 93 Meridian 2 DXF layers Layer name G8053000 G8053001 G8053002 G8053004 G8053500 G8053501 G8056140 G8056142 G8056155 G8056730 G8056731 G8056401 G8056403 G8056405 G8056800 G8056411 G8056415 G8056710 G8056711 G8056200 G8056740 G8056741 G8056300 G8056310 G8056720 G8056721 G8056801 G8056500 G8056551 G8050575 G8050571 G8050572 G8050573 G8056223 G8056224 G8056225 G8056230 G8056231 Feature name Motorway A road B road Minor road Road node Road edge node Railways Tunnelled railway Station Railway node Railway edge node County boundary District boundary London borough unitary authority County district London borough unitary authority boundary Boundary neat line County seed District seed Boundary node Boundary edge node Coastline Coastline node Coastline edge node DLUA boundary DLUA seed DLUA node DLUA edge node DLUA neat line Place name Station name Default Footnotes Grid lines and values Grid values
106. tabase Feature Classification Record defines data classifications Section Header Record defines coordinate and structure types unit scale factors and so on Attribute Record defines the attributes for line and point records Point Record identifies the definition of node points Node Record defines the topological relationship between links and nodes Two dimensional Geometry Record defines the two dimensional geometry for a link or node Line Record identifies the definition of a link Attribute Description Record defines attribute descriptions and their fields Text Record identifies the Text Position Record and Attribute Record Text Position Record identifies the Text Representation Record and Geometry Record Text Representation Record defines the font text height and digitised position Comment Record transfers change information or information about empty tiles Volume Terminator Record defines the end of the transfer set Record name VOLHDREC DBHREC FEATCLASS SECHREC ATTREC POINTREC NODEREC GEOMETRY 1 LINEREC ATTDESC TEXTREC TEXTPOS TEXTREP COMMENT VOLTERM NOTE Where Meridian 2 height differs from Meridian 2 full dataset a record example will be shown Meridian 2 technical specification chapter 4 v5 2 02 2007 Crown copyright Page 38 of 93 Volume Header Record VOLHDREC 01 Field Position
107. tails of the Layer Table can be seen in Meridian 2 DXF layers in chapter 5 Figure 6 7 Style Table level 3 Key one or more o optional ENDTAB STYLE GROUP DEFINITIONS Figure 6 8 C RRNNMNN M RENI Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 70 of 93 The Style Table will contain the text file load instructions for e SIMPLEX SHX e MONOTEXT SHX Figure 6 8 Level 4 Key one or more STYLE DEFINITIONS STYLE STANDARD FIXED TEXT WIDTH GROUP FLAGS HEIGHT FACTOR GROUP GROUP GROUP PRIMARY FONT FILE NAME GROUP BIG FONT FILE GROUP Blocks Figure 6 9 Level 2 Key o one or more BLOCKS o optional SECTION SECTION START ENDSEC GROUP Figure 6 10 BLOCKS GROUP SECTION START 00 Meridian 2 technical specification chapter 6 v5 2 02 2007 Crown copyright Page 71 of 93 Figure 6 10 Level 3 Key one or more BLOCK BLOCK LAYER BLOCK GROUP GROUP NAME X Y Z E GROUP GROUP GROUP ENTITIES Entities section The Entities Section will contain DXF entities for e Ordnance Survey map footnotes data INSERT entities e Grid and neatline TEXT and LINE entities and e Ordnance Survey features TEXT POLYLINE and INSERT entities Extended entity data will be used to store attributes The structure of each different entity is as follows a INSERT entities these consist of
108. ted in products services or publications that you generate for onward sale or as free promotional or support materials without the prior written consent of Ordnance Survey Trademarks Ordnance Survey the OS Symbol Land Form PANORAMA Land Line Landranger and Strategi are registered trademarks and Boundary Line and Meridian are trademarks of Ordnance Survey the national mapping agency of Great Britain Arclnfo ArcView and ESRI are registered trademarks of Environmental Systems Research Institute Inc AutoCAD and Autodesk are registered trademarks and DXF is a trademark of Autodesk Inc Helvetica and Univers are registered trademarks and Times is a trademark of Heidelberger Druckmaschinen AG MapInfo is a registered trademark of MapInfo Corporation Using this specification The documentation is supplied in portable document format PDF only Free Adobe Acrobat Reader software which displays the specification incorporates search and zoom facilities and allows you to navigate within Hyperlinks are used to navigate between associated parts of the specification and to relevant Internet resources by clicking on the blue hyperlinks and the table of contents Ordnance Survey is committed to providing customers with consistently high quality geographic information As such Ordnance Survey regularly applies several data quality measures to the product and the associated documentation These quality measurements are based on the principles
109. tion tile Broadly synonymous with digital map file it implies evenly sized map sheet units topographic database A database holding data relating to physical features and boundaries on the Earth s surface topography Topography is the study of the physical features of the Earth A topographic map s principal purpose is to portray and identify the features of the Earth topology The study of the properties of a geometric figure that is not dependent on position such as connectivity and relationships between lines nodes and polygons transfer format The format used to transfer data between computer systems In general usage this can refer not only to the organisation of data but also to the associated information such as attribute codes which are required in order to successfully complete the transfer transfer medium The physical medium on which digital data is transferred from one computer system to another For example CD ROM transfer set A specific NTF term for the data together with its supporting information which the customer receives update The process of adding to and revising existing digital map data to take account of change vector A straight line joining two data points vector data Positional data in the form of coordinates of the ends of line segments points text positions and so on volume A physical unit of the transfer medium that is a single disc RN Meridian 2 technical specification
110. to the Earth This is normally considered to involve a spatially referenced computer database and appropriate applications software geometric structure The ground is modelled in the data as a series of lines and points gigabyte Gb 1 073 741 824 bytes a measure of data storage capacity grid The planimetric frame of reference For example the National Grid hard copy A print or plot of output data on paper or some other tangible medium junction A connection between two or more links at a common node kilobyte Kb 1 024 bytes a measure of data storage capacity MU V iiL Meridian 2 technical specification annexe A v5 2 02 2007 Crown copyright Page 85 of 93 layer A subset of digital map data selected on a basis other than position For example one layer might consist of all features relating to roads and another to railways line A series of connected coordinated points forming a simple feature with homogeneous attribution line feature The spatial abstraction of an object in one dimension Lines may intersect with other lines They are defined as a series of two or more coordinates and may be curved or straight Curved lines consist of a series of very short straight line segments Lines may be concurrent with other lines under certain conditions As an object abstraction a line has no width line segment A vector connecting two coordinated points linear feature Map feature in the form of a line for examp
111. ture to which it belongs Ordnance Survey distinguishes between layer name types for example place names and station names by placing each name type in a separate layer Text has position expressed as a single coordinate pair held as X and Y offsets from the map origin south west corner If there are any double or treble banked names they will be treated as two or three separate features Anchor points at the bottom left hand corner and digitising positions define the text string content Text is oriented that is it may run from west to east across the map or it may be plotted at some angle measured anticlockwise from grid east RN Meridian 2 technical specification chapter 7 v5 2 02 2007 Crown copyright Page 77 of 93 Drawing content and format Coordinate system The coordinate system is National Grid NG The National Grid coordinates are to a resolution of 0 1 m This is the resolution of the source data Height Height information is produced in the form of DTM style data Gridded height information is averaged from the 50 m resolution Land Form PANORAMA dataset to a resolution of 200 m and rounded down to the nearest 1 m value See chapter 2 in the technical specification Layer names MapInfo supports long file names This allows you to use up to 260 characters when naming your file In addition any one name within your directory path can be up to 255 characters You can insert spaces in the file name and long fil
112. tween nodes junctions uninterrupted by tile or map edges An OSODR refers not just to a single link but may refer to many links that make up a road object which may be chained together across tile edges Thus on adjoining tiles there may be two or more links with the same OSODRs This attribute applies to links and nodes It will be present for all features An OSODR has been assigned to all existing features links and nodes in the Roads database Any features that are new to Roads after the initial allocation will be assigned an OSODR when they are loaded to the database RN Meridian 2 technical specification chapter 2 v5 2 02 2007 Crown copyright Page 21 of 93 The OSODR for a feature will never be modified only created and deleted However there may be many changes to a feature with a specific OSODR during the lifetime of that OSODR allocation There are two reasons for changes These are 1 The coordinates of the feature may move within a specified tolerance currently 3 m either side of a link 1096 of its length and 5 m movement of any node 2 The attributes associated with a feature may change Any changes to these attributes will not affect the OSODR allocated to that feature The following attributes may change for link features The following attributes may change for node features e date of survey of conversion e direction of links at node e feature code e feature code e length of link e junction name
113. ur customer contract and this guide then the terms of your customer contract prevail If you or your organisation has not signed a valid current customer contract then you are not entitled to use the product Purpose and disclaimer This guide is provided for guidance only and does not constitute any warranty representation undertaking commitment or obligation express or implied about the product or its suitability for any particular or intended purpose Any warranties representations undertakings commitments and obligations given by Ordnance Survey about the product and or its suitability for any particular or intended purpose are set out in your customer contract It is your responsibility to ensure that this product is suitable for your intended purpose Ordnance Survey does not accept any liability whether for breach of contract negligence or otherwise for any loss or liability you or any third party may suffer in relying on this guide and any guidance suggestion advice or explanation provided in it Any liability that Ordnance Survey has to you in relation to the product its supply use accuracy data supplied functionality or any other liability arising out of or in connection with the product is limited as set out in your customer contract We may change the information in this guide at any time without notice We do not accept responsibility for the content of any third party websites referenced or accessed in or through thi
114. used to navigate between associated parts of the guide and to relevant Internet resources by clicking on the blue hyperlinks and the table of contents The guide provides an introduction to the structure and content of the product and assumes a general knowledge of geographic information It also gives guidelines and advice on how a customer might derive the maximum benefit from the product If you are unfamiliar with any words or terms used and require clarification please refer to the glossary at the end of the document E Meridian 2 user guide preface v5 2 02 2007 Crown copyright Page 4 of 93 Chapter1 Introduction Concepts of Meridian 2 are explained fully in chapter 2 Meridian 2 is supplied as data only and does not include software for data viewing or manipulation Meridian 2 is supplied in NTF or DXF will require specific software such as GIS or CAD NTF is a nationally agreed standard for the transfer of geographical data NTF allows users of GIS to customise their own definition of the data for display and or plotting for their specific applications Meridian 2 is also available as data in Mid Mif and Shapefile formats which require specific software such as Maplnfo Professional or ArcView The database has been derived from Ordnance Survey s existing large and small scale digital databases Meridian 2 features e Meridian 2 has feature codes that allow everything in the database to be allocated to a specific catego

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