Then, the geometrical feature of lips in human face is proposed to increase the accuracy and speed of lip locating. Two key characteristics were found. One is that the ratio of lip color area to that of skin color is almost unchanged.

• 然后利用嘴唇在人脸区域的几何分布特性 ；来提高唇动定位的速度和准确性 ；唇动定位主要利用两种几何分布特性 :(1)利用唇的区域面积和人脸的区域面积比值变化范围不大这一特性自适应确定区分唇色和肤色的阈值 .