Raster images

[Grass package]

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Steve Culshaw writes:
> 
> I've imported a black and white GIF image into GRASS - the image is a 
> raster Ordnance Survey 1:10,000 map - problem is it's 60 Mbytes in size 
> and we have about 700 of them.
> I assume that the large size is because GRASS is storing each pixel as a 
> byte, whereas the GIF image is using a single bit to represent each pixel.
> 
> My question is 'Is there any way to store the image in GRASS at bit 
> level' and so reduce the file storage to a more reasonable level.
> 
One thing you can do is r.compress the files as soon as they are converted
to grass raster maps. With 0/1 images, this will result in a huge reduction
in file size.  But from your map numbers I'd say you may still need some
3.5 GB filespace - better consider vectorising each image.

        Martijn

P. Martijn van Leusen -------------------------------------------------------+
Leverhulme Research Fellow, The Wroxeter Hinterland Project                  |
University of Birmingham Field Archaeology Unit                              |
Edgbaston, Birmingham B15 2TT                                                |
Phone +44 121 414 5513  Fax +44 121 414 5516  E-mail P.M.van-Leusen at bham.ac.uk