[GRASS-user] Not being able to produce decent-look color-composites

[Michael Barton]

Also, it usually helps to do a histogram equalization on each band prior to compositing. i.landsat.rgb does some of this kind of enhancement automatically.

Michael


On Feb 13, 2012, at 10:00 AM, <grass-user-request at lists.osgeo.org> wrote:

> Date: Mon, 13 Feb 2012 17:22:50 +0100
> From: Markus Neteler <neteler at osgeo.org>
> Subject: Re: [GRASS-user] Not being able to produce decent-look
> 	color-composites
> To: Luisa Pe?a <luisapena1979 at gmail.com>
> Cc: GRASS user list <grass-user at lists.osgeo.org>
> Message-ID:
> 	<CALFmHhsgPqEwaBUcTTicFzDY=Z7mZr9ozMGgU+Vcc=v0cpFzXQ at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
> 
> On Mon, Feb 13, 2012 at 12:50 PM, Luisa Pe?a <luisapena1979 at gmail.com> wrote:
>> Greetings
>> 
>> I'have 3 layers of Landsat (Green, Red and Near-Infrared) and I'm trying to
>> produce a false-color composite?(r.composite(?with those but... I'm getting
>> very frustrated because I'm producing very bad look composites. My layers
>> are reflectances from 0-1.8 or something. Shall I rescale them to 0-255?
> 
> Did you try with i.landsat.rgb? I didn't check if it works with
> reflectance, too.
> 
> BTW: I just added a screenshot example to
> http://grass.osgeo.org/grass64/manuals/html64_user/i.landsat.rgb.html
> 
> Markus
> 

_____________________
C. Michael Barton
Visiting Scientist, Integrated Science Program
National Center for Atmospheric Research &
University Corporation for Atmospheric Research
303-497-2889 (voice)

Director, Center for Social Dynamics & Complexity 
Professor of Anthropology, School of Human Evolution & Social Change
Arizona State University
www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu