[FWTools] gdal_merge with -ps optoin is giving the following error

[Frank Warmerdam]

mzorova wrote:
>>From looking at samples from around the web, I think I might have
> mis-interpreted the -ps option to be specifying the dimensions of the output
> file.
> 
> Then the issue I am facing is different - without the ps (which I guess
> defaults to 1x1) the output file is exactly the same size of the first file
> - all the files are copied into starting at 0,0 - it does not seem to be
> using the GCP's specified in the file to actually tile them (each of these
> files is adjacent to one another - forming four quadrants of a larger
> rectangle).

Mzorova,

You are correct, gdal_merge does not understand anything about GCPs.
It only looks at the geotransform.

I think you should try gdalwarp instead of gdal_merge.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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