[GRASSLIST:3510] Re: How to correct SRTM data

Hamish hamish_nospam at yahoo.com
Fri Apr 9 02:01:23 EDT 2004


> > I'm looking for ways to correct srtm data. I found that r.mapcalc
> > can correct mountain holes by interpolating GTOPO and SRTM data.
> >
> > Can you gis gurus give me some pointer about correcting speckled
> > sea? And what about sea level and coastline?
>
> You can use the gtopo30 dataset to define your coastline.  Everything
> that is null in gtopo30 can be made null in you SRTM dem using mapcalc
>
> r.mapcalc srtm2 = 'if(isnull(gtopo30),gtopo30,srtm1)'
> 
> This gives a blocky coastline though (gtopo30 is ~900m resolution
> compared with~30 or ~90 for SRTM).


Not if you run 'r.buffer dist=900' on the gtopo30 map first.



Hamish




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