head tracking

managed to set up the opencv with the sample face detection code.
some issues:
- very high lag (possible solutions: reduce image size?)
- in some cases, incorrectly detecting my ears or other parts as a face
- at certain angles or head tilt, unable to detect the face at all (possibly need additional haar cascade data?) --- how to detect heads at unusual angles (rolls don't work, mean if the face is facing front, but the image is rotated 45 deg, the face is not recognized)?

additional stuff:
- opencv has additional training data to detect: face, profile face, upper body, lower body, full body


additional research on head tracking:

http://danielbaggio.blogspot.com/2008/01/webcam-opengl-opencv-head-tracking.html

he made a 3d environment that changes viewing angle based on head position (note, there's no roll, yaw, pitch -- only coordinates).

however, he found a way to make face detection faster from 200ms, down to 20ms, though it involves modification of the opencv code itself.

his blog: http://danielbaggio.blogspot.com/
also mentions ECHI api, which is some code that uses opencv.
echi: http://code.google.com/p/ehci/

features of echi includes:
6 degree of freedom head tracking (what we're doing)
head tracking
hand tracking

check out the youtube video of 6-dof head tracking:
http://www.youtube.com/watch?v=M5kqgBO6D9s
http://www.youtube.com/watch?v=NNVaU2eOcbs (awesome!)