[GRASS-dev] Problems with r.out.gdal byte export: colors modified in RGB multilayer GeoTIFF

[Markus Neteler]

Hi,

On Wed, Feb 10, 2016 at 10:23 AM, Vincent Bain <bain at toraval.fr> wrote:
> I recently experienced some buggy image color table management by Qgis,
> did not dig much deeper. Sorry if my case may be the exact inverse of
> yours, but I finally did it to obtain a more "faithful" color rendering:
>
> - composited an initial 3-band image
>         r.composite [...]
> - then exported it with
>         r.out.gdal [...] format=GTiff type=UInt16
> - and expanded it again to a 3-band rgb image via :
>         gdal_translate -expand rgb [...]
>

Thanks for the tip. We tried and the colors are better but a black "no
data" area came back which I managed to remove in GRASS GIS.
How complicated :)

> Anyway, since Qgis Lyon, we have some trouble wih image color
> management.

We checked and the yellowish white also shows up in Geoserver. So I
guess it is a GDAL/GeoTIFF issue at this point.
Perhaps worth a GDAL ticket?

Markus