Face Detection algorithms

Does anyone know a good algorithm for Face Detection in
color and grayscale images?. I have been looking at some
algorithms based on Neural Networks and Ellipse Detection.

i search like you an algorithm for Face Detection in
color and grayscale images?. if you have algorithms based on Ellipse Detection please send it to me.

Have you checked out:
http://www.cs.colostate.edu/evalfacerec/

http://www-2.cs.cmu.edu/afs/cs.cmu..../ftp/faces.html

http://home.t-online.de/home/Robert.Frischholz/face.htm

http://research.microsoft.com/~szli/FR-Handbook/

I'll admit I've never worked on face recogntion, but I have done a little with OCR and I can't imagine how you'd process something as hugely complicated as a face in color. Given the number of angles that the face could be viewed from and the number of possible configurations (smiling, squinting, etc), throwing color in on top of that seems like it would just make a super difficult job tougher. But those links should give you a start.