[GRASS5] zlib compression for CELL maps

Glynn Clements glynn at gclements.plus.com
Wed Jan 4 13:10:51 EST 2006

Jaro Hofierka wrote:

> I have a problem with a size of integer (CELL) maps. It is strange that 
> the size of compressed integer maps is bigger than the same maps in 
> floats.

FP maps use zlib; integer maps use run-length encoding.

> Recently, we tried to import srtm files and floating point maps 
> took much less disk space then integers :-(
> I tried to use the GRASS_INT_ZLIB variable, but the compression flag in 
> a header file is still set to 1 (should be 2?). Problably I missed 
> something.

Did you export it, e.g.:


or (bash-specific):

	export GRASS_INT_ZLIB=1

Glynn Clements <glynn at gclements.plus.com>

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