Geospatial PDF

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   Hi,

I am wondering whether QuickPDF supports georeferenced PDF in accordance with ISO 32000.

I've made use of QuickPDF for processing GeoPDF files (TerraGO) through the 'GetPageLGIDictContent' API and all is well.  However I would also like to read the geo data from so called geospatial PDF's where the geo data is encoded in accordance with 'Adobe Supplement to ISO32000'.  

Any assistancew would be appreciated.

Lee

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bakerlp Members Profile Find Members Posts Beginner Joined: 21 Sep 10 Location: England Status: Offline Points: 3	Post Options Post Reply Quote bakerlp Report Post Thanks(0) Quote Reply Topic: Geospatial PDF Posted: 21 Sep 10 at 1:22PM
	Hi, I am wondering whether QuickPDF supports georeferenced PDF in accordance with ISO 32000. I've made use of QuickPDF for processing GeoPDF files (TerraGO) through the 'GetPageLGIDictContent' API and all is well. However I would also like to read the geo data from so called geospatial PDF's where the geo data is encoded in accordance with 'Adobe Supplement to ISO32000'. Any assistancew would be appreciated. Lee

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3529	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 21 Sep 10 at 9:03PM
	Hi Lee! Perhaps this link can help? http://www.quickpdf.org/forum/geopdf_topic1321_post6394.html?KW=geospatial#6394 Real support you won't get from the current version of QuickPDF. Cheers and welcome here, Ingo

bakerlp Members Profile Find Members Posts Beginner Joined: 21 Sep 10 Location: England Status: Offline Points: 3	Post Options Post Reply Quote bakerlp Report Post Thanks(0) Quote Reply Posted: 21 Sep 10 at 10:01PM
	Ingo, Many thanks for the reply. The link you refer to seems to be discussing geopdf's in accordance with "GeoPDF Encoding Best Practice Version 2.2" which can be processed using Quickpdf's API GetPageLGIDictContent. I downloaded the 'Intelligence Collection using GeoPDF' geopdf from 'http://acrobatusers.com/gallery/geospatial' and the the value returned from GetPageLGIDictCount is zero hence there doesn't seem to be any geo-reference data embedded. However, If I open the file in Acrobat Reader 9 then I can view the Lat/Long via the acorbat 'Analysis' menu hence there is some geodata in the file somewhere, its just how to extract it. Many thanks Lee

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3529	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 22 Sep 10 at 6:36AM
	Hi Lee! Do you know what are the special signs, characters, ... from "these geospatial things" in the pdf-content? If "Yes"... why not search inside the pdf-content programmatically by yourself to extract the relevant content? I've done similar things with javascript- and xml-code... Cheers, Ingo

bakerlp Members Profile Find Members Posts Beginner Joined: 21 Sep 10 Location: England Status: Offline Points: 3	Post Options Post Reply Quote bakerlp Report Post Thanks(0) Quote Reply Posted: 22 Sep 10 at 9:40AM
	Hi Ingo, Unfortunately I do not know the tags/signs involved (if there are any). I simply downloaded the file and tried to process it as if a TerraGO GeoPDF. If the geo-reference data is encoded in accordance with ISO 32000 (Extension Level 3) (using entries in a viewport dictionary) then is this supported by QuickPDf. If yes then a heads up on the API's involved would be very much appreciated. Ingo...apologies but I'm very new to PDF programming so I may be asking rudimentary questions. Thanks Lee

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3529	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 22 Sep 10 at 2:24PM
	Hi Lee! You can get more from inside as you can imagine ;-) Load the pdf and save it decrypted. Then take notepad and search directly into the content. Perhaps you can find the special strings... keep it in mind... and use it later programmatically ;-) Have a look in my blog regarding this case to get an idea about what you can do: http://pdfcomments.blogspot.com/2009/09/under-surface.html Cheers, Ingo

cosina Members Profile Find Members Posts Beginner Joined: 28 Sep 10 Status: Offline Points: 1	Post Options Post Reply Quote cosina Report Post Thanks(0) Quote Reply Posted: 28 Sep 10 at 11:11PM
	I'm also very intereted in Adobe's own Geospatial specification support (of course just in a matter of reading/writing a proper section) Documenation: http://www.adobe.com/content/dam/Adobe/en/devnet/pdf/pdfs/adobe_supplement_iso32000.pdf 8.8.1 Geospatial Features Sample file: http://www.avenza.com/sites/default/files/spatialpdf/US_County_Populations.pdf

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3529	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 29 Sep 10 at 6:33AM
	Hi! Thanks for the sample link. If you do like i've suggested opening the pdf with notepad you'll find this section regarding Geospatial: /Type /Measure /Bounds [ 0.000000 0.000000 0.000000 1.000000 1.000000 1.000000 1.000000 0.000000 ] /GCS 218 0 R /GPTS [ 35.662407 -94.909767 36.294361 -94.899741 36.284127 -94.028131 35.652254 -94.046095 ] /LPTS [ 0.500000 0.500000 0.500000 0.518145 0.513570 0.518145 0.513570 0.500000 ] /PDU [ /M /SQM /DEG ] /Subtype /GEO >> endobj 218 0 obj << /Type /PROJCS /WKT (PROJCS["North_America_Albers_Equal_Area_Conic",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137,298.257222101]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],PROJECTION["Albers"],PARAMETER["false_easting",0],PARAMETER["false_northing",0],PARAMETER["latitude_of_origin",40],PARAMETER["central_meridian",-96],PARAMETER["standard_parallel_1",20],PARAMETER["standard_parallel_2",60],UNIT["Meter",1]]) >> endobj Cheers, Ingo