On 4/25/12 5:01 AM, Glynn Clements wrote:
Benjamin Ducke wrote:
But as far as I can see, there is not yet a way to completely
prevent rasters from being compressed at creation time?
That's correct. IIUC, Maris is just suggesting that we have one
variable to select between no compression, RLE, and zlib, rather than
one variable to enable or disable compression and another to select
the compression algorithm.
The same principle can be applied to the implementation. Currently,
R__.compression_type will be either 1 (RLE) or 2 (zlib). Rather than
adding a separate R__.use_compression field, we can just set
R__.compression_type to 0 to indicate no compression. That is
consistent with the "compressed" field of the Cell_head structure.
Agreed -- little reason to use two different variables to describe three
mutually exclusive choices involving compression.
However, the existing GRASS_INT_ZLIB variable only applies to integer
rasters, correct? Although in all cases this variable does indeed
dictate whether the Cell_head "compressed" field is set to 1 or 2,
AFAICT put_fp_data ignores it and uses zlib for writing compressed
floating point rasters in either case. Is this intentional?
Jim
_______________________________________________
grass-dev mailing list
[email protected]
http://lists.osgeo.org/mailman/listinfo/grass-dev
