人脸表情识别代码，演示了识别过程中每个步骤，通过肤色变化提取人脸区域，寻找最大联通区域，人脸区域二值化，左眼、右眼嘴唇分割和边缘提前，最后通过三个特征进行表情识别。包含测试图片。-Facial expression recognition code demonstrates each step in the identification process, by the color change of extract facial area, looking for maximum Unicom