[mapserver-users] GetCoverage and palette Geotiffs

[Alexander Petkov]

On Mon, Oct 27, 2008 at 11:43 AM, Frank Warmerdam <warmerdam at pobox.com> wrote:
> Alexander Petkov wrote:
>>
>> Would it be possible to preserve the original data in an image (number
>> of bands, and Type, and color interp) in the result of a GetCoverage
>> request? For example, I serve Paletted  Geotiffs through mapserver:
>
> ...
>>
>> Any hopes of being able to preserve the orig data after a GetCoverage
>> request?
>
> Alex,
>
> The original pixel values can be preserved by picking an IMAGEMODE BYTE
> outputformat, but unfortunately that will currently discard the palette.
>
> Basically there are two major rendering paths involved here. One is a
> map view oriented one (GD'ish renders - IMAGEMODE RGB, RGBA or PC256) and
> the other is a raw data oriented path (GDAL'ish renders - IMAGEMODE BYTE,
> INT16 and FLOAT32).
>
> We could look at trying to preserve palettes and possible some other stuff
> in the "raw data" case but I'm not terrible keen on doing this.

What are the drawbacks of preserving the original color palette in
"raw data" mode?

Thanks,
Alex