Realistic Facial Animation Review : Based on Facial Action Coding System

Making realistic facial animation is one of the most challenging research topics in facial animation field because producing realistic photo and sentimental virtual characters require a combination of face modeling , animating, and rendering. Techniques that commonly used for facial animation are in need of naturalism. The most popular expression coding systems are FACS (Facial Action Coding System) and MPEG-4 (Moving Pictures Experts Group-4) Facial animation models. FACS is a landmark technique that enables remarkable improvements in making realistic facial animations. Where MPEG-4 Facial Animation provides a standard way of encoding facial actions by defining various parameters for a talking face. In this paper, we made a review on how to achieve realistic facial animation, focusing on the applications and limitations of the FACS comparing to MPEG-4 facial animation. The review inferred that FACS helps animators to represent and build realistic facial expressions by configuring all possible facial animation units of the human face.