Identification of micro expressions in a video sequence by Euclidean distance of the facial contours

This paper presents an automatic facial micro-expression recognition system (FMER) from video sequence. Identification and classification are performed on basic expressions: happy, surprise, fear, disgust, sadness, anger, and neutral states. The system integrates three main steps. The first step consists in face detection and tracking over three consecutive frames. In the second step, the facial contour extraction is performed on each frame to build Euclidean distance maps. The last task corresponds to the classification which is achieved with two methods; the SVM and using convolutional neural networks. Experimental evaluation of the proposed system for facial micro-expression identification is performed on the well-known databases (Chon and Kanade and CASME II), with six and seven facial expressions for each classification method.