A Divendres, 26 de març de 2010, Phil Endecott va escriure: > Dear Experts, > > I need to extract the geolocation metadata from a GeoPDF file. > > If you're not familiar with this format, it's something that was > developed by a company called TerraGo Technologies and was adopted as a > "best practice" by the Open Geospatial Consortium. There is a document > describing it via http://www.opengeospatial.org/standards/bp (look for > "GeoPDF"; click-through but free-looking license required). Basically > it provides a method to associate positions in the document with > latitude-longitude positions on the ground. > > The method used is to define "map frames" that are added to the parent > PDF page object. As I understand it, there is a new key 'LGIDict' in > the page object, which is an array of dictionaries one per map frame, > each of which contains a set of entries like containing matrices, > bounding boxes etc. that define the geolocation for that frame. > > My hope is that it would be possible to write a small program that > would open the PDF file and iterate through the pages, dumping this > data as it is found. I have had a look at the pdfinfo program which > seems to be doing something similar for other metadata. > > Would anyone be able to help me with this?
Don't really count on that, if you want this done, doing it yourself is safest bet to get it done. > I am a competent C++ coder > but have never had to understand much about how PDF works. Is starting > with pdfinfo sane? Yeah as good as any other thing > How do I access the page objects? Is there a way > to iterate through the entries in a dictionary? You haven't looked at the code right, because it's quite straighforward. > > Or, maybe there is already some other tool that will do this? Not that i know > > Here's an example of a GeoPDF file: > ftp://ftp2.cits.rncan.gc.ca/pub/cantopo/50k_pdf/092/g/cantopo_092g06_pdf.z > ip > > > Many thanks for any advice. Good luck! Albert > > > Regards, Phil. > > > > > _______________________________________________ > poppler mailing list > [email protected] > http://lists.freedesktop.org/mailman/listinfo/poppler _______________________________________________ poppler mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/poppler
