[GRASS-user] output values of r.composite

[Glynn Clements]

Markus Metz wrote:

> On Wed, Jan 28, 2015 at 10:34 PM, Micha Silver <micha at arava.co.il> wrote:
> > When I use r.composite to create, i.e., a false_color composite from three
> > Landsat bands, the RGB values in the composite are slightly different than
> > the values in the original bands. Why is that?
> 
> Because the number of levels to be used for each component is by
> default 32, not 256 [0].

You can use levels=256 if you want 256 levels. But the resulting map
will have a very large colour table (65536 rules), which will
negatively affect the performance of anything which reads the colour
table. Which is why the default is 32 levels rather than 256.

-- 
Glynn Clements <glynn at gclements.plus.com>