With technology, I guess there is no need for special camera to capture facial expression and input into an Avatar. Now, a Keio University group, led by Associate Professor Yasue Mitsukura, has developed a method for measuring which way a person is facing and how their expression changes.
Previously, I thought we need special markers on the face to allow the avatar to trace the facial expression. Now, it seems that a standard webcam can do the trick. Watch the video.