[gdal-dev] getcolortable is null

[Frank Warmerdam]

weixj2003ld wrote:
> I read a geotiff file, and find that
> poBand->GetColorTable()==NULL

Wei,

Presumably GetColorTable() returns NULL because the GeoTIFF file
does not have a color table.

> But I use ERDAS IMAGINE9.2 (a software that deal with geotiff), I find 
> that it is not grey,but I use "gdal_translate -b 6 -of JPEG old.tif 
> net.jpg", find that is is grey.

Well, you are selecting only one band withouta color table to export
to net.jpg.  How do you expect it to be anything other than greyscale?
If you want an RGB jpeg file then select three bands to be used as
red, green and blue.

eg.
gdal_translate -b 4 -b 5 -b 6 o-of JPEG  old.tif net.jpg

Best regards,

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