mogrify and GeoTiff

[Frank Warmerdam]

Travis Kirstine wrote:
> Hi all,
> I would like to colour reduce some geotiffs using mogrify however when
> running the command all geo-reference header info is stripped.  Does anyone
> off hand know the command option to keep the coord info?

Travis,

You can use the listgeo utility to dump the geotiff tags to a text file
from the original file.  Then use geotifcp to "reapply" the geotiff tags.
I think this is covered in the GeoTIFF FAQ at:

   http://geotiff.maptools.org/faq.html#preserve_metadata

The FWTools suite includes the listgeo and geotifcp programs if
you don't already have them handy.

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