[GRASSLIST:72] Re: d.rgb question

[Markus Neteler]

On Fri, May 16, 2003 at 03:08:54PM -0500, Kirk R. Wythers wrote:
> I have used r.in.gdal to import a rgb tif (it is a scanned map). I'd
> like to display it as it looks when I view it with gimp. r.in.gdal
> imported the tif as test.1, test.2, and test.3 (I assume for the 3 color
> bands).

BTW: I have updated r.in.gdal to write in this case
test.blue, test.green, test.red
and to apply a grey scale color table.
The new version should come with 5.0.3 (or get the source code from CVS).

> After reading though some man pages, it looks like d.rgb is what
> I should use to superimpose all 3 bands (hopefully getting something
> that looks "colorwise", like the original tif). 

Yes.
 
> However, no matter which order I "superimpose" the color bands with
> d.rgb, I can not get anything to look like the original. I am using the
> wrong function here, or perhaps just applying it incorrectly?

You have to assign a grey color table first:

r.colors test.1 col=grey
r.colors test.2 col=grey
r.colors test.3 col=grey
d.rgb ...

Hope this helps,

 Markus Neteler