A Comprehensive Survey on Face Expression Recognition

Facial expressions provide an important behavioral measure for the study of emotions, cognitive processes and social interaction. Facial Expression Recognition (FER) is process performed by computers which consist of detect the face in the image and preprocess the face region, extracting facial expression features from image. There have been several advances in the past few years in terms of face detection and tracking, feature extraction mechanisms and the techniques used for expression classification. This paper presents a time-line view of the advances made in this field, the key challenges and the classifications of FER.