[gdal-dev] Meteosat 2nd Gen projection (MSG GEO)

[Frank Warmerdam]

Jose Luis Gomez Dans wrote:
> Hi,
> I have some data from MSG, in ENVI format. The raster file does not have any projection information, and I would like to reproject it into WGS84. After some lurking about the GDAL codebase, it appears that the proj4 invocation is given by "+proj=geos +h=35785831 +a=6378169 +b=6356583.8". So I set up to reproject my file:
> 
> $ gdalwarp -of GTiff -t_srs "EPSG:4326" -s_srs "+proj=geos +h=35785831 +a=6378169 +b=6356583.8" \
> input_file.dat output_file.tif
> ERROR 1: Unable to compute a transformation between pixel/line
> and georeferenced coordinates for input_file.dat
> There is no affine transformation and no GCPs.
> 
> Is this the right way of doing this? There's very little information on this projection anywhere.

Jose,

What does the gdalinfo report on the input file look like?  I believe the
problem is that GDAL does not even know the coordinates for the input file
in the GEOS projection.  That is, it has no geotransform for the file.  This
isn't a projection problem so much as a basic georeferencing problem.

The issue could be in the ENVI driver, or it could be that the data is
not georeferenced at all.

Best regards,
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