Image/image mode/index?
..."quantize" to N colors , Posterize to N colors Convert to index with a palette of N colors are very similar operations offering very similar results
Gimp already compress quite well PNG,you can't do more without loosing a main point of ( RGBA)PNG a looseness quality
what pngnq and similar programs doe is "quantize" http://members.ozemail.com.au/~dekker/NEUQUANT.HTML
File size decrease and the quality decrease in proportion
If what you wish well there is not A gimp plugin , but are variants of pngnq for all OS, including Windows and Mac here a few link
http://pornel.net/pngnqhttp://pmt.sourceforge.net/pngcrush/
the pngnq examples http://pngnq.sourceforge.net/pngnqsamples.html seems work well also because because the originals well chosen:
the originals are rgb photo but with few, and well defined colors,so the quantized version look almost as the original
i doubt used on other images will give similar results.
Sometimes, but usually only a few percent of the original size.
I wouldn't bother to run this on a single file to squeeze it down by a few KB. If you have a large number of files and plan to distribute them, however, running pngcrush or optipng on them can save some MB.
any luck on finding one? I
PNG That is not Compression
AFAIK the compression done
Ah!...do you know if the
Sometimes, but usually only
Sometimes, but usually only a few percent of the original size.
I wouldn't bother to run this on a single file to squeeze it down by a few KB. If you have a large number of files and plan to distribute them, however, running pngcrush or optipng on them can save some MB.