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I have downloaded a historical USGS map that is suppose to be a geoPDF. My understanding is that QGIS cannot directly read geoPDF's. I have not had any luck in converting it to a geoTIF in order to bring into QGIS.

  1. Has anyone had any success in doing this? Is there another way that someone knows to use the geoPDF with QGIS.

  2. I converted the geoPDF to a TIF and attempted to use the georeferencer plug-in. Everytime I try doing it te results are not correct.Georeferender screenshot Georeferencer result

  • Where is the source pdf located? I would use river/road intersections as reference points. Also knowing the pixel size (dpi) will help too. – Mapperz Oct 18 '13 at 14:00
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    @Mapperz: You will find the GeoPDF sources here: geonames.usgs.gov/pls/topomaps. Search for NY Newburg. – AndreJ Oct 18 '13 at 14:46
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    Are those red dots your control points? If so, they're not in the right location. They should be at the graticule marks at the corners of the actual data, not the edges of the map sheet. – mkennedy Oct 18 '13 at 14:47
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    By the way, you got X and Y swapped. -74 is West (X), and 41 is North (Y). And 74 is once positive in your GCP. – AndreJ Oct 18 '13 at 14:59
  • @Andre: I should have posted the website. I wanted to attached the geoPDF, but file size was huge. You are correct, I always get them backwards, I will retry. – LandArch Oct 18 '13 at 18:55
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You are right that QGIS can not (yet) read GeoPDF, but GDAL 1.10.0 can do it.

Assuming you are on Windows, you can download the current version from

http://www.gisinternals.com/sdk/.

GDALwarp can transform your GeoPDF into geoTiff:

gdalwarp -of Gtiff NY_Newburg_144216_1903_62500_geo.pdf Newburg.tif

Make a batch file with that content, start the SDKshell.bat, then run the converter batch. The output can be read by QGIS without the need to georeference: enter image description here

(With a little help by underlaying Openstreetmap from the Openlayers plugin)

  • I can start another thread if you think I should. Do you have any knowledge of doing what you mentioned above, but stripping out the borders of the map. This would allow me to tile more than one in QGIS without having the borders hide information. – LandArch Oct 18 '13 at 19:43
  • This can be done by the -cutline parameter in gdalwarp. But that should be answered in a different question. – AndreJ Oct 19 '13 at 5:02

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