[gdal-dev] gdal_translate adding 'dashed' lines to output

John Gray jgray at graysolutions.com
Thu Jan 23 13:49:33 PST 2014


I've been trying to use "gdal_translate" to convert a USGS GeoPDF to a 
GeoTiff file.  It appears to be working correctly except for one issue.  
During the conversion a number of horizontal lines appear in the 
output.  They appear at a few latitudes in the file - it looks like a 
dashed line across the image with a lot of space between each dash (but 
you have to zoom in to see them).  When I view the produced GeoTiff file 
in an image viewer here is what I see (zoomed in and cropped):

http://www.graysolutions.com/temp/LenexaLines.png

I've circled the improper lines in this image.  When I view the GeoPDF 
in Acrobat these lines do not appear (so I do not believe they are part 
of the source image).

Has anybody seen this problem before or know how to keep it from happening?

---------

Additional Details:

For the example above I rendered only the raster orthoimage layer, 
however when the full contents of the file are rendered I still see the 
'dashes' in the output.

The source GeoPDF file I'm working with can be downloaded here (~25 MB, 
downloads as a .zip file):

http://ims.er.usgs.gov/gda_services/download?item_id=5689818

I'm using GDAL compiled for Windows from 
http://www.gisinternals.com/sdk/.  I tried using both the 'stable' and 
'development' versions and the results were the same (running on Windows 
8.1).  The command line used:

gdal_translate -of GTiff --config GDAL_PDF_LAYERS "Images.Orthoimage" 
--config GDAL_PDF_DPI 150 KS_Lenexa_20120905_TM_geo.pdf Lenexa.tif

I'm using the DPI setting to scale the image down so the output isn't so 
large (without this it is a ~950 MB file).  I did render one without 
setting this (rendering at the native resolution) and the dahses were 
still there.  I've also tried this for other GeoPDF files in the same 
series and experienced similar results.

Thanks,

John



More information about the gdal-dev mailing list