After discovering some relatively inexpensive IP enabled Pan and Tilt cameras on Deal Extreme (http://www.dealextreme.com/details.dx/sku.14272) I thought I'd see if I could get them working with ZoneMinder (http://www.zoneminder.com/) - a free Linux based video surveillance recording package.
They were relatively simple to setup and get working. ZM works great with these cameras with the motion jpeg stream, and only requires a little bit of modification to make the Pan/Tilt functions work. ZM's motion detection works great and its sensitivity is very configurable but can be fairly complex.
One big caveat is the amount of CPU required to do all of this. Two cameras doing monitor only (no motion detection) used 60% cpu continually on an old Athlon 1400 test server. Motion detection on even one camera shoots cpu to 100% and things really suffer. It seemed to be able to achieve about 20 FPS, but this may be a limitation of the MJPEG server. I tested dropping the frame rate in ZM, but that didn't help CPU usage at all. I suspect a lot of the CPU time is spent receiving the video stream from the camera and whatever processing happens here. I figure for the purposes of this project I can live without full motion video - 5FPS should be plenty, so I figure I may be able to use the single jpeg frame grab functionality so the ZM capture process has a bit less work to do.
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