Human emotions are used in our daily lives to help facilitate interactions among other human beings and can be expressed using verbal and non-verbal cues, i.e.
facial expressions and body language. Facial expressions are important cues for non-verbal communication among human beings as humans have the ability to accurately recognize emotions. Emotion recognition is the process of identifying human emotion, which can be done using computational technologies. To improve emotion recognition technologies, socially intelligent software tools have been created, allowing a robot or machine to predict human emotions which in turn enhances its effectiveness in performing various tasks. An automatic facial emotion recognition system is a vital component in human-machine interaction.
Most of the facial expression recognition methods reported to date are focused on recognition of the six primary expression categories such as: Happiness, anger, sadness, fear, disgust and fear. Accurately understanding the emotional intention of others is very important in interpersonal communication. Emotional recognition dysfunction impairs interpersonal relationships and lowers quality of life.