<snip>
> Those .png icons are a serious pain to retouch--they're not even true
> pixel art, and
> I think someone downscaled most of them from larger or vector originals.
> Which
> we don't have, of course. :(

The best solution I have found (which is far from ideal of course!) is to
use hqx to upscale the largest image available as much as possible.  This
them becomes the master image, and all the other images are regenerated
from it as needed.

Tim