TY - JOUR T1 - Recognizing human facial expressions from long image sequences using optical flow JF - IEEE Transactions on Pattern Analysis and Machine Intelligence Y1 - 1996 A1 - Yacoob,Yaser A1 - Davis, Larry S. KW - Computer vision KW - Eyebrows KW - face recognition KW - facial dynamics KW - Facial features KW - human facial expression recognition KW - HUMANS KW - Image motion analysis KW - image recognition KW - image representation KW - Image sequences KW - Motion analysis KW - Motion estimation KW - Optical computing KW - optical flow KW - symbolic representation KW - tracking AB - An approach to the analysis and representation of facial dynamics for recognition of facial expressions from image sequences is presented. The algorithms utilize optical flow computation to identify the direction of rigid and nonrigid motions that are caused by human facial expressions. A mid-level symbolic representation motivated by psychological considerations is developed. Recognition of six facial expressions, as well as eye blinking, is demonstrated on a large set of image sequences VL - 18 SN - 0162-8828 CP - 6 M3 - 10.1109/34.506414 ER -