[GRASS5] Re: [GRASSLIST:2848] Re: import raster
neteler at itc.it
Mon Mar 8 11:28:16 EST 2004
On Fri, Mar 05, 2004 at 05:58:43PM +0000, Glynn Clements wrote:
> Markus Neteler wrote:
> > > I've a problem importing some raster:
> > > I use r.in.gdal to import a raster and the results are files over 100 mb for
> > > every raster.
> > > With r.compress I reduce to 17,4 mb.
> > > Is there a method to reduce again these files?
> > > I think that GRASS take the raster as a 8 bit image while the original is
> > > black and white (1 bit)
> > Anything to improve in r.in.gdal (we all like small files)?
> If the file is being compressed, the underlying format (1/2/4 bytes)
> won't make much difference.
> The only way to get any significant reduction in the file sizes would
> be to use zlib (or similar) rather than RLE compression.
Do you refer to CELL type only? For FCELL/DCELL deflate should
be used aready, right?
To change from RLE to deflate (zlib) compression would need an
update for all CELL maps, I assume (a pity that it wasn't done
when we eliminated LZW).
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