[GRASSLIST:109] Re: making a "true-color" landsat composite

[Markus Neteler]

Dylan,

On Tue, Mar 14, 2006 at 10:04:52AM -0800, Dylan Beaudette wrote:
> Markus,
> 
> Nice images!
> 
> a couple things:
> 
> 1. the link at the top of the page had some interesting polar plots.
> For hard copy I found that ps.rose in the GMT suite produces excellent
> results as well:
> http://169.237.35.250/~dylan/NPS/day100.png

yes, there is also some R extension for that.
I just thought to have it directly in GRASS (6.1-CVS).
Someone may change the xgraph output to d.graph for consistency,
cannot be hard (hey, maybe you?).
 
> 2. the color boost technique -- is your script available on the GRASS
> wiki somewhere, or in the grass scripts dir in a recent CVS branch?

Sure...

> This looks like it will do the trick, now the only problem is that I
> have just put together the entire state of Arizona with the poor
> looking imagery!

Sorry - I had written the script three weeks ago but didn't advertise it
yet.


I have added parser support today, get it now from
http://mpa.itc.it/markus/grass61/demos/
-> i.landsat.rgb

6.1-CVS is needed as it uses a new feature of r.univar.sh.

> thanks for the tips,

cheers

 Markus


 
> Dylan
> 
> 
> On 3/14/06, Markus Neteler <neteler at itc.it> wrote:
> > Dylan Beaudette wrote:
> >
> > >Hi everyone,
> > >
> > >I was working on constructing some "true color" landsat composite images today
> > >from bands 3,2,1 -- and came across some strange inconsistencies. Data from
> > >one source produces "nice" true color images:
> > >
> > >http://casoilresource.lawr.ucdavis.edu/drupal/node/211
> > >
> > >whereas, another source produces somewhat muddy true color composites. I tried
> > >playing a bit with an equalized grey colormap for each band via r.colors
> > >color=grey.eq with the following results:
> > >
> > >http://casoilresource.lawr.ucdavis.edu/drupal/node/215
> > >
> > >
> > >Does anyone have any tips on how to tweak color ramps for the various bands so
> > >as to get a better looking "true color" composite?
> > >
> > >
> > how do you like this LANDSAT:
> >  http://mpa.itc.it/markus/grass61/demos/
> >  -> LANDSAT 7 color boost
> > ?
> >
> > Markus
> >

-- 
Markus Neteler     <neteler itc it>       http://mpa.itc.it
ITC-irst -  Centro per la Ricerca Scientifica e Tecnologica
MPBA - Predictive Models for Biol. & Environ. Data Analysis
Via Sommarive, 18        -       38050 Povo (Trento), Italy