A binocular vision system and its application to face detection and tracking in robot is introduced in this paper. With the
vision system, the robot can do face detection, identification, recognition and tracking. The face area is detected in realtime
by using AdaBoost algorithm. And a method is proposed with which a real face can be distinguished from a picture
one by using skin color information and depth data. A specific face can be recognized by comparing the principal
components of the current face to those of the known individuals in a face database built in advance. Finally, the robot
can track a specified face according to depth of the face and position of a face rectangle in the frame. Experiment results
are given and discussed.