[gdal-dev] grey output from gdal2tiles.py

[Frank Warmerdam]

Wendell Turner wrote:
> I used gdal2tiles.py to convert a GeoTIFF file into a
> directory for use with OpenLayers.  The tiles are generated,
> and can be viewed with OpenLayers, but the tiles are all
> gray.  There appears to be some structure to the images, but
> they do not have any colors, and little detail.
> 
> The input file looks fine in gtviewer.
> 
> Is the input to gdal2tiles supposed to be in some other
> format?  It uses gdal.Open, which I suppose can open any
> type of file format.  Any suggestions?

Wendell,

I don't know what gtviewer is.  Can you make the original file available
to review?  I suspect it has a very limited dynamic range and the viewer
you are using for it directly does a contrast stretch, but this doesn't
happen with the tiles in openlayers. Alternatively, perhaps it doesn't
start out as an RGB image as is expected by gdal2tiles.

So basically, review the input file structure (a gdalinfo report will
help) vs. what gdal2tiles expects as input.

Best regards,
-- 
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