On mercredi 4 avril 2018 11:13:29 CEST Simon Proud wrote: > Hello, > I am trying to visualise GOES-16 data, but the output projection from > gdal_translate appears faulty. > This is the command I use: > gdal_translate -a_srs "+proj=geos +a=6378137. +units=m +no_defs > +b=6356752.31414 +x_0=0.0 +y_0=0.0 +ellps=GRS80 +lon_0=-75.0 > +f=.00335281068119356027 +h=35786023. +sweep=x" -a_ullr $ulx $uly $lrx > $lry [input_file] [output_file] >
Simon, This has been discussed recently on the list. Basically the issue is that GeoTIFF encoding has no way to represent this projection properly. Long version at http://geotiff.maptools.narkive.com/3CqwNeMd/geos-projection-sweep-parameter A potential workaround is to have a .tif + .tif.aux.xml file and forcing a baseline TIFF to be produced In GDAL master, I've just committed a fix so that gdal_translate input.tif output.tif -co PROFILE=BASELINE -a_srs "+proj=geos +a=6378137. +units=m +no_defs +b=6356752.31414 +x_0=0.0 +y_0=0.0 +ellps=GRS80 +lon_0=-75.0 +f=.00335281068119356027 +h=35786023. +sweep=x" works With currently released versions, you have to do a more convoluted approach 1) Create a baslilne TIFF file gdal_translate input.tif output.tif -co PROFILE=BASELINE 2) Create a dummy png file (1x1) with the projection info in .aux.xml gdal_translate -of PNG test.tif output.png -a_srs "+proj=geos +a=6378137. +units=m +no_defs +b=6356752.31414 +x_0=0.0 +y_0=0.0 +ellps=GRS80 +lon_0=-75.0 +f=.00335281068119356027 +h=35786023. +sweep=x" -srcwin 0 0 1 1 3) Rename output.png.aux.xml to output.tif.aux.xml 4) Check with "gdalinfo output.tif" that you get the right projection info Even -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/gdal-dev
