Recognizing degree of continuous facial expression change

Describes a method for recognition of continuous facial expression change from time-sequential images. The method is composed of two parts, (1) facial feature tracking by using a labeled graph matching with weighted links and (2) facial expression recognition by making a comparison between the trajectory of features and the expression change model. The expression change model is constructed by using B-spline curves, which represent the relationship between the motion of facial features and the change of expression. Not only the type, but also the degree of expression change can be recognized. Furthermore, the obtained expressional information is then fed back to guide the tracking in the next frame