Hi,
just committed paletted image support.
Just add palette=safe to your getMap request to have the standard palette, or drop a png8 or .gif file into data_dir/palettes and use
the file name as the palette name to have that palette used to
generate the image.
The format name will still be image/png, it will simply be a png8
when a 8bit palette is used for rendering.
Let me know how your tests go. For me, the statepop png drop down
from 40 to 10 kb, and to only 7 if I use gif instead of png.
Cheers
Andrea