[GRASS-user] r.in.srtm help, again

[antonio rodriguez]

> 241 * 421 * 2 = 202922.   Your file has 614 too many bytes. Header info?
>
>
> I have the GEBCO bathy loaded into a lat/lon location here (sort of),
> which I did back in Nov 2005.
>
> Looking through the history I used this method-
>
> Note the .jpg I used does not contain absolute depths.
> The .jpg I have is 21601x10801 (1' +1), 6190902 bytes, greyscale.
> gdalinfo:
> Band 1 Block=21601x1 Type=Byte, ColorInterp=Gray
>
>
> In a simple XY location:
>
> r.in.gdal in=gebco_bathy.21601x10801.jpg out=gebco_bathy
> r.region gebco_bathy n=90 s=-90 e=180 w=-180
> g.region rast=gebco_bathy
> r.out.mat in=gebco_bathy out=/tmp/grass/gebco_bathy.mat
>
>
> In a Lat/Lon location:
>
> r.in.mat /tmp/grass/gebco_bathy.mat
> r.colors gebco_bathy col=grey
>
>
> I may have done some adjustment in Matlab, it is too long ago to
> remember. Probably I just used r.out.mat and r.in.mat to load the data
> into a lat/lon location without "lat>90" type errors. The final z-scale
> is 0-255, so that isn't much good for quantitative analysis. At minimum
> it needs scaling. Maybe better r.region details to cover the (60*360)+1
> too?
>
>
> <http://www.ngdc.noaa.gov/mgg/gebco/grid/1mingrid.html>
> Looking at the "free download" website I give up in a sea of online
> registrations and "buy the full CD here". :-/
>
>
> As an alternative, the etopo2 dataset is pretty nice and includes the 2
>   
> Smith & Sandwell satellite altimetry ocean bathymetry. (See the article in
> GRASS Newsletter vol. 1)
>
>
> Hamish
>
>   

Hi,

What I've done is convertig the .grd file to an xyz one trough grd2xyz. 
Then in Idirisi, import it, rasterize and export as a Geotiff file. Then 
in GRASS, import to an xy location the tiff image.

The problem now in GRASS is when trying to make a vector file of the 
raster one I'm forced to use r.thin first, which erase almost all the 
data, outputing a blank map.

Cheers,

Antonio

Antonio