It requires recent versions of imlib (not imlib2) and libcurl. I develop it under Red Hat Linux. I haven't intentionally put anything Linux-specific into it, but I don't test it anywhere else, and I'm not intimately familiar with the subtle differences between libc's and such, so YMMV.
camwatch works for me, rather poorly. It will probably work even worse for you. Let me know.
camwatch was originally written by 'cblack,' but his website has disappeared and his last known email address bounces. So, I've appropriated the project; if anyone knows this cblack and want to direct me to him, I'd love to get in touch and see if he wants it back or wants to pass it to me more formally.
You can get it, such as it is, at its github page.