Computer facial animation has many applications in different aspects, e.g. realistic virtual humans with various facial expressions used in the industry of entertainment and edutainment. In communication applications, it can improve the interaction between users and machines by using interactive talking faces, and can also attract users by providing a friendly interface. Fred Park 1974 was the first who showed interest in facial animation. He is also the first who used the power of 3D computer graphics in a way that delivered the highest level of control that drives the acts of a face. Applications at that time included computer generated actors and a rich research instrument for those studying the field of non-verbal communication and human facial expression.
As the online game manufacturing develops fast, it requires users to improve, greater quality of the graphics, and to achieve a significant feat in artificial intelligence. These elements motivated the gaming industry full with priceless artificial intelligence and graphics like real photos. Initially, the games consisted few number of polygons in characters and were supported by a few active computers in that regard. Presently, the characters in the game appear to be more natural, but there are still challenges in expressing the emotions of characters in a detailed way. However, several colour model researches were only capable of proposing the facial colour model (Buddharaju et al., 2005; Kalra and Magnenat-Thalmann, 1994; Yamada and Watanabe, 2004) that are based on pulse, skin temperature and real human blood flow. These mentioned techniques end up conveying the color of the face with an increasing redness (Kyu-Ho and Tae-Yong, 2008).