A comprehensive study on Facial Expressions Recognition Techniques

Motion of one or more than one muscles underneath the skin is Facial Expression. These movements plays very important role in conveying the emotional states of individual to the observer. Human face-to-face communication is important in human interaction. In recent years, different approaches have been put forward for developing methods for fully automated facial expressions analysis that is important for human computer interaction. In Facial Expression Recognition System the image is processed to extract such information from it, which can help in recognizing six universal expressions that are neutral, happy, sad, angry, disgust and surprise. This processing is done in several phases including image acquisition, features extraction and finally expressions classification. This paper surveys some of the techniques that are used for the purpose of facial expression recognition; a summary of some of the papers from 2001 to 2012 is given in tabular form. A list of few challenges in this field is given at the end along with the possible future advancements.