Capture Facial Expressions from live video

I want to capture the 4 basic following facial expressions with Kinect/Webcam - Surprised (eyebrows raised), Sad, Happy(smile),Angry (frown) Once captured you can display a basic message on the screen. Doesn't have to be very complete, this is for a demo, if it works for 1-2 people - that should be fine. This should work on a Kinect sensor connected to a PC.