[GRASS-user] stream extraction from ASTER dem

[Markus Metz]

Milton Cezar Ribeiro wrote:
> Hi Markus,
>  
> May be you are right (Vista issue!). Two month ago I was trying to run 
> the same steps on grass, but I was expecting that new OSGeo4W release 
> included some fix for that. :-(
That problem of r.watershed on Vista 64bit (I assume you use Vista 64bit 
because of 6GB RAM) showed up before. I guess the basic problem is that 
wingrass is 32bit because msys and gcc coming with msys and OS-specific 
include files are all 32 bit. A 32bit application can't use all 6GB. It 
would be interesting to see if other modules with huge RAM requirements 
also fail on Vista 64bit. Anyway, valgrind and gdb did not show me 
anything on Linux. Try GRASS on XP or Linux if possible, there it should 
work.

Good luck,

Markus M

>  
> Anyway, thanks for your time.
>  
> Any colleague that could suggest a way of I extract some 
> geomorphometry features (sensu Tom Hengl!) from "large" DEM 
> (10,000x6,000), please let me know.
>  
> bests
>  
> milton
>
> 2009/9/28 Markus Metz <markus.metz.giswork at googlemail.com 
> <mailto:markus.metz.giswork at googlemail.com>>
>
>
>     Milton Cezar Ribeiro wrote:
>
>         Dear all,
>          I have a DEM with dimensions 10,000 x 6,000. Now I need to
>         extract all the stream or drainage, as well as generated some
>         other stream/flow related features like flow direction,
>         stream lenght, etc.
>          I work on a computer with 6Gb under Vista, and the grass
>         version is the OSGeo4W one. But when I try to run the command
>         below I get one error relate to r.watershed.seg.exe:
>          r.watershed elevation=aster_dem stream=aster_dem_stream
>         threshold=150 -m memory=2048
>          Any idea of how to solve that?
>
>     Maybe it is the Vista UAC problem, there were recently other posts
>     related to this.
>
>     Just a guess,
>
>     Markus M
>
>