[mapserver-users] Optimising Image quality

[Stephen Lime]

There is a patched version of GD 1.8.4 that supports GIF/JPEG/PNG and WBMP.
I removed gd-1.2 mainly because this version existed. Visit:

  http://www.rhyme.com.au/gd/ 

Steve

Stephen Lime
Data & Applications Manager

Minnesota DNR
500 Lafayette Road
St. Paul, MN 55155
651-297-2937

>>> Tim Sutton <sutton_t at giug.net> 10/24/01 03:22AM >>>
Hi

I have the cvs mapserver running. I am trying to improve the quality
of the map output. If I use jpeg, the images (comprised mainly of
lines and labels) have quite a lot of 'noise'. I suspect the jpeg
output would be more suitable for maps containing raster backdrops
(large colour palettes with few areas of contiguous colour). I can't
use PNG as it is not universally supported by browsers yet.

Can anyone tell me where to get hold of the GD1.2 so that I can create
GIF's on the fly? The GD project site no longer lists it (for
obvious reasons I suppose).

Alternatively, is there any way to improve the quality of jpeg images
produced? I have tried the IMAGEQUALITY [int] paramter. Although the
documentation does not explicitly state it, I presume [int] is a
percentage 0-100 value. I tried the extremes in this range with no
visible improvement in image output quality.

Any suggestions will be greatly appreciated.

Thanks

Tim