[Gdal-dev] RasterIO on bands with ColorTable

[Frank Warmerdam]

On 5/4/05, Sheykhet, Rostic <rsheykhet at sanz.com> wrote:
> Hello,
> 
> I am trying to perform RasterIO on a band that references a color table.
> When the source and destination image dimensions are different, I get
> back a band that has indexes into blank/invalid color table entries.  I
> assume this is because of the decimation procedure.  Is there a way to
> modify this behavior?

Rostic,

RasterIO() level resampling should all be "nearest neighbour", and so
not introduce any new values.   Is it possible you have built overviews
on the file in question with averaging?  Perhaps the format is a lossy
compression format? 

Best regards,
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