Recognizing facial expressions by spatio-temporal analysis

An approach for analysis and representation of facial dynamics for recognition of facial expressions from image sequences is proposed. The algorithms the authors develop utilize optical flow computation to identify the direction of rigid and non-rigid motions that are caused by human facial expressions. A mid-level symbolic representation that is motivated by linguistic and psychological considerations is developed. Recognizing six facial expressions, as well as eye blinking, are demonstrated on a collection of image sequences.