[GRASS-user] Calibrating colors of a series of maps

[Jan Hartmann]

Hi Folks,

I am working with series of old topographical maps, rangnig from 10 to 
600 map sheets per map. Each sheet is discolored a bit from age. How can 
I process a complete series in such a way that there are no differences 
visible any more between map sheets? Preferably I would like to 
downsample them to 8 bits color table, as the originals only have a 
small set of colors. In other words: how do I calibrate s set of maps to 
the same optimal color table?

Jan