[gdal-dev] changing white pixels to transparent

[Andreas Neumann]

Hello!

I have 1bit (b+w) input GeoTIFF files and want to change them to 8bit gray
value pixels where the white bits are set to transparent. I had a look at
the gdal_translate and GeoTIFF options but did not find a way to
accomplish this task. Maybe I have overlooked some parameters/switches?

If this can't be accomplished with gdal - can you recommend another tool,
preferably a commandline tool?

Thanks,
Andreas

-- 
Andreas Neumann
Böschacherstrasse 6, CH-8624 Grüt/Gossau, Switzerland
Email: a.neumann at carto.net, Web:
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