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I don't see what I am doing wrong. The coordinate system was assigned to the GeoTiff using the following gdal_translate command:

(Usage: gdal_translate -of GTiff -a_srs EPSG#### -a_ullr upper left lower right source.tif target.tif)

gdal_translate -of GTiff -a_srs EPSG:29191 -a_ullr 567.4 8321.8 571.4 8318.8 c5100102_pdf_clipped2boundary.tif output01.tif

followed by

gdalwarp -t_srs EPSG:29191 output01.tif final01.tif

This last step did not work.

Did I miss something?


I have gotten this far:

enter image description here

Something is still missing, as Tiff does not align perfectly with the vectors. Reprojecting rasters is a new area for me.

  • The numbers in the gdal_translate command don't match 29191 which is SAD69 UTM zone 21 South. Are you giving the values in kilometers? (If so, the data's in Brazil) They should be given in meters. – mkennedy Sep 10 '15 at 16:47
  • Correct, it is in Brazil. The values, I assume, are in meters. Meta data was not included with this file. The tiff can be seen at gis.stackexchange.com/questions/162190/convert-tiff-to-geotiff – RJP Sep 10 '15 at 17:26
  • Well, they're not in meters--way too small for a UTM zone (which always uses meters). What happens if you change the -a_ullr to: -a_ullr 567400.0 8321800.0 571400.0 8318800.0 ? – mkennedy Sep 10 '15 at 17:29
  • That made a difference! Thanks! Now the GeoTiff is off from the reference by 1000 to 1500 meters – RJP Sep 10 '15 at 17:51
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Alternatively to the corner coordinates, you can georeference against OpenStreetmap or Google Satellite imagery with QGIS and the Openlayers plugin.

From that, I get this picture:

enter image description here

which clearly shows that the imprinted coordinates are wrong. The image is rotated on an arbitrary point near the lower right corner.

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