image processing- i.composite?

[Wang Song]

	Try to run i.grey.scale (linear stretch contrast) for each three bands 
before running i.composite.

Song Wang
CAST, University of Arkansas


> I'm trying to use the GRASS image processing facilities on some 
> landsat data.  But I am unable to produce a satisifactory composite 
> image.  Have have tried using i.composite and i.colors.  Both the 
> images produced are far too dark with only the clouds showing as 
> white patches.  As both of these operations start I get the the 
> message:
> WARNING: histogram file missing (or something like)
> 
> i.colors should be interactive but it would operate for me other than to 
> resize the image and swap bands.
> 
> Tom Charnock               
> Dept Civil Engineering     
> Aston University          
> Birmingham UK                           
> charnotw at aston.ac.uk     
>