I just use the v4l2 api directly for a ps3 eye. I started with this:
http://linuxtv.org/downloads/v4l-dvb-apis/capture-example.html
and ripped out the non-mmap buffer methods. It's a bit simpler than it looks.
But if you just want a png/jpeg maybe with some text or something, you could just use ffmpeg's command line interface. Do a search to find the arguments - it's pretty simple, and could even do low-rate video if you wanted to, as well as text overlays and so forth. If it isn't in angstrom it's fairly easy to build stand-alone.
Michael