r.resamp.rst smoothing parameter

classic Classic list List threaded Threaded
4 messages Options
Reply | Threaded
Open this post in threaded view
|

r.resamp.rst smoothing parameter

Frank Broniewski-2
Hi List,

I have some kind of probability map with a resolution of about 90m. Now I want
to resample this map for press information print. The map has some kind of
distortions where you have small areas (just a few cells) where the values
change quickly and the map looks very "turbulent".

I want to use r.resamp.rst for this purpose, and I experimented already with
the tension parameter. But this alone does not give me satisfactory results.
From the manual I take it that there is also a smoothing parameter where one
can give a smoothing raster as parameter. But I really have no clue how this
raster should look like.

Taking the vector version of r.resamp.rst one can give a number as smoothing
value which is pretty easy to understand ;-), but what kind of values are
expected for the smoothing raster? Can I just give a constant raster map as
smoothing parameter with a value of e.g. 0.1? Then why use a raster map as
parameter?

I hope someone can light up a candle for me!

Greetings Frank
_______________________________________________
grass-user mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-user
Reply | Threaded
Open this post in threaded view
|

Re: r.resamp.rst smoothing parameter

hamish-2
Frank Broniewski wrote:
> I have some kind of probability map with a resolution of about 90m.
> Now I want to resample this map for press information print. The map
> has some kind of distortions where you have small areas (just a few
> cells) where the values change quickly and the map looks very
> "turbulent".

smooth it with a r.neighbors mean or median filter?


Hamish



      ____________________________________________________________________________________
Be a better friend, newshound, and
know-it-all with Yahoo! Mobile.  Try it now.  http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ 


_______________________________________________
grass-user mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-user
Reply | Threaded
Open this post in threaded view
|

Re: r.resamp.rst smoothing parameter

Frank Broniewski-2
r.neighbors was exactly what I was looking for. Sometimes I really get lost in
the functionality of GRASS ;-)
But just to satisfy my curiosity: How should a smoothing raster for
r.resamp.rst look like or how would I create one?

Best whishes

Frank

On Wednesday 30 January 2008 13:04:51 Hamish wrote:

> Frank Broniewski wrote:
> > I have some kind of probability map with a resolution of about 90m.
> > Now I want to resample this map for press information print. The map
> > has some kind of distortions where you have small areas (just a few
> > cells) where the values change quickly and the map looks very
> > "turbulent".
>
> smooth it with a r.neighbors mean or median filter?
>
>
> Hamish
>
>
>
>      
> ___________________________________________________________________________
>_________ Be a better friend, newshound, and
> know-it-all with Yahoo! Mobile.  Try it now.
> http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ


_______________________________________________
grass-user mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-user
Reply | Threaded
Open this post in threaded view
|

Re: r.resamp.rst smoothing parameter

Markus Neteler
On Jan 30, 2008 4:45 PM, Frank Broniewski <[hidden email]> wrote:
> r.neighbors was exactly what I was looking for. Sometimes I really get lost in
> the functionality of GRASS ;-)
> But just to satisfy my curiosity: How should a smoothing raster for
> r.resamp.rst look like or how would I create one?

The SRTM to generate the LANDSAT image at
http://www.grassbook.org/neteler/rs/landsat7/index.html

was brought to 14.25m resolution with  r.resamp.rst. I don't remember,
possibly I did a two-steps interpolation.

Markus
_______________________________________________
grass-user mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-user