[Gdal-dev] gdal_merge.py Gtiff files with -pct losing color

[Frank Warmerdam]

Izzy wrote:
> Hi,
> I am trying to compose a geotiff satellite image by stitching several 
> satellite geotiff images.
> All of them are one band images with same pseudo color table. 
> When merging the images with -pct to preserve the color table, I get a 
> black image.  When I don't use this option, I get a fainted final 
> picture since the color is now Grey Scale.
> 
> I noticed that the pseudo color table for each of the input images look 
> different if I use gdalinfo and ImageMagick command identify. 
> I attached the gdalinfo and IM info files for one of the input 
> images:AS_GMSNO_gdalinfo.dat and AS_GMSNO_IMinfo.dat and the gdalinfo of 
> the output image obtained using gdal_merge.py  with and without "-pct" 
> option(out-pct_gdalinfo.dat and out_gdalinfo.dat).

Izzy,

The gdalinfo report of the color table in AS_GMSNO_gdalinfo.dat is clearly
badly messed up.  Is this your input file?  Can you provide it to me for
closer inspection?

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