Converting color photos to RGB images

[Leslie Apollon]

At 02:49 PM 8/17/98 -0700, you wrote:
>Hi everybody,
>
>I have a query I am hoping someone can help with. I have a series of old
>color photographs of an area which I need to scan and study to see how it
>has changed. Is there any algorthm to convert a composite color photograph
>into individual RGB intensities? Is there a unique way of doing so? Or
>even a heuristic which may have some (hopefully estimatable) degree of
>error in back-converting? How do people usually deal with this?
>
>Thanks,
>
>Harini Nagendra
>

One of the features of the r.mapcalc program is a function that extracts
the color
components ( red, green and blue) of a raster file. the syntax is:    

         r.mapcalc red_output_map = r#input_map    
         r.mapcalc green_output_map = g#input_map    
         r.mapcalc blue_output_map = b#input_map


------------------------------------
Leslie Apollon, M.Sc. Conseiller SIG - Support Technique

Global Geomatics Inc.(formerly L.A.S. Inc.)
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