PNG libraries

[Lutger]

Lodepng was designed not to do everything the PNG format is capable of 
since that makes it easier to do what png is most used for: image 
loading / saving. However, the way the recent iteration is coded will 
make it easy, with a few minor changes, to implement an extensible api. 
It does have the benefit of supporting the full range of color formats 
and generally being spec compliant already.

If you are interested in making use of lodepng or extending it to an 
editor, I'm open to discussion and willing to help.