I. Introduction
Emotion is considered as an important characteristic of human beings and they use it to cover their words directly. These emotions can be expressed through our expression of face, human made conversations, gestures and attitude too. Many individuals approach the next person on the basis of emotion that they make on their face. According to research done by the psychologists Mehrabian et al, facial expressions by humans are quite essential in human daily communication, with a transmission rate of 55%, far more significant than the speech (38%), language (7%), and so on [1]–[5].