[Gdal-dev] Problems with gtiff projections

[Frank Warmerdam]

Roger James wrote:
> Frank,
> 
>  
> 
> I create a new geotiff dataset, set the projection from wkt that has 
> projection parameters in it, and then save it. When I read it back in 
> the projection parameters are missing. For a transverse mercator these 
> are things like the lat/long origin and the false easting/northing etc.
> 
>  
> 
>  From a quick look at the code the routine GTIFGetProjTRFInfo might be a 
> culprit as it always fails because the file "projop_wparm.csv" cannot be 
> found.

Roger,

What version of GDAL are you using?  How are you creating and writing
the projection to the file.  I ask because in GDAL 1.1.8 there was a bug
in writing the projection to files created with the Create() method, while
those created by the CreateCopy() were OK.

If that isn't the issue (the problem is fixed in CVS), then I will need
further details.  Generally speaking if you provide the full set of
projection parameters when writing a GeoTIFF file, then GDAL should be able
to read and interprete the file properly when reading even if projop_wparm.csv
isn't found.  If there is a glitch in this I would like to know, but I will
need details of how to reproduce.  For instance, what was the WKT you were
writing, and what is the listgeo *and* gdalinfo reports on the resulting file?

Best regards,

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