Saturday, June 28, 2014

GDAL to convert GeoPDF to GeoTIFF - the Windows version

I needed to convert GeoPDF files to GeoTIFF.  I'm not command-line savvy.  So I was hesitant to try this.  When the gdal_translate command failed no matter what I tried, I nearly gave up.  (I can just screen-shot the PDFs.  Right!)  

But I kept digging.  I found that not all GDAL installs support PDF.  I had to get a specific set of GDAL binaries for Windows.  Here's how and why:


I'm doing volunteer/non-profit work to publish map services that show georeferenced map layers for historic maps of  Caroline County, Maryland.  I'm using MapTiler, Tileserver, QGIS, and ArcGIS Online for low-cost production and publishing.  Recent products are:

1875 and 1897 county and towns via AGOL and
- 1897 county in OpenLayers.

Next task is to publish similar services and maps from the USGS Topo GeoPDFs.  I need to convert the GeoPDFs to GeoTIFF in order to publish the tiles as a service.  (Esri has done this already.  But only for paying customers.)

I found a tutorial for using GDAL's gdaltranslate utility.  After installing GDAL and cursing my way through the godawful Windows command line window, I kept getting GDAL errors.  GDAL wasn't recognizing the PDF format.

Why not?  I was following the tutorial steps exactly.  I checked forums and found that GDAL has PDF support in some releases but not in others -- it was working for Ubuntu installs, but not for all Windows installs.   The tutorial used the Ubuntu installer.  I had used the OSGeo4W installer for GDAL.  That one does not include PDF support.  Gotta love opensource.

I found a pointer to GDAL binaries I needed at gisinternals.com.  I downloaded the zipfile with the files that are right for my Windows system.  Simply unzipped the file in a folder.  Then ran the SDKShell.bat file.  No need to install anything.  That worked for me.  Gotta love opensource.







6 comments:

  1. The NOAA scanned t-sheets are a great resource for historical coastal maps. geotiffs/Google Earth overlays/reports:
    http://specialprojects.nos.noaa.gov/tools/shorelinesurvey.html

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  2. G-Raster does this conversion after you pay the $5 registration charge.
    http://moagu.com/?page_id=155

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    1. This comment has been removed by the author.

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    2. Wish I had known. Thanks for the tip.

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  3. >> similar services and maps from the USGS Topo GeoPDFs...
    This link is for historical USGS topo maps only. For the current USGS map series, see http://nationalmap.gov/ustopo/ and http://www.usgs.gov/faq/categories/9797. For USGS info on GeoPDF to GeoTIFF, see http://www.usgs.gov/faq/categories/9797/3704

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