[gdal-dev] Using a specific earth model

[Frank Warmerdam]

Andrea Battisti wrote:
> 
>> from a GeoTIFF file, then I would have expected PCI to write
>> the proper spheroid info into the geotiff file, and for GDAL to pick it
>> up.  If this is the situation, I'd appreciate seeing a "listgeo" report
>> on the file.  Listgeo is part of libgeotiff and should be available in
>> FWTools distributions.
>>
> 
> 
> The file is generated by other people and unfortunately I have no
> control over it.
> I guess some PCI software has been used, I am asking for details.
> Does it sounds like there is a missing auxiliary file?
...
>    Keyed_Information:
>       GTModelTypeGeoKey (Short,1): ModelTypeProjected
>       GTRasterTypeGeoKey (Short,1): RasterPixelIsArea
>       GTCitationGeoKey (Ascii,17): "SIN         E019"
>       GeographicTypeGeoKey (Short,1): User-Defined
>       GeogAngularUnitsGeoKey (Short,1): Angular_Degree
>       ProjectedCSTypeGeoKey (Short,1): User-Defined
>       ProjectionGeoKey (Short,1): User-Defined
>       ProjCoordTransGeoKey (Short,1): CT_Sinusoidal
>       ProjLinearUnitsGeoKey (Short,1): Linear_Meter
>       ProjFalseEastingGeoKey (Double,1): 0               
>       ProjFalseNorthingGeoKey (Double,1): 0               
>       ProjCenterLongGeoKey (Double,1): -82             
>       End_Of_Keys.
>    End_Of_Geotiff.

Andrea,

This geotiff file is incomplete and has no earth model information.  It
ought to at least define the spheroid.  It would appear to be written by
the PCI software directly.  While I wrote the PCI GeoTIFF exporter originally
while working there, that's no excuse for them not fixing it after I left!

More seriously, this is an incomplete file, and you would need to use
some manual override mechanism to provide the ellipsoid now.

Best regards,
-- 
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