[GRASS-dev] GRASS raster compression & performance

[Glynn Clements]

Markus Neteler wrote:

> Meanwhile I discovered the .xz file format:
> http://en.wikipedia.org/wiki/Xz
> http://tukaani.org/xz/format.html
> 
> Maybe worth to be implemented in GRASS?

Container formats such as .gz or .xz aren't relevant.

We could offer LZMA compression (the algorithm used for .xz files) as
an alternative to deflate (zlib), but LZMA is much slower.

There are some benchmarks on the XZ site:

	http://tukaani.org/lzma/benchmarks.html

If anything, I would expect that the difference in file size would be
less for GRASS rasters than for typical files because of the small
chunk sizes (each row is compressed separately).

-- 
Glynn Clements <glynn at gclements.plus.com>