Abstract: Active Shape Models（ASM） is one of powerful tools for face alignment，face recognition and facial expression recognition.However，the performance of ASM is often influenced by some factors such as the initial location，illumination and so on.This paper proposes an improved active shape models.First，the position of eyes which provide roughly the initialization position for point distribution model of ASM is detected in face region using Point Contour Detection Method（PCDM）.Second，a new method constructed local appearance model is developed.This improved method is evaluated on JAFFE face database and the experimental results show that the improved ASM improves the accuracy of face features location.Finally，an artificial neural network is constructed to recognize facial expression and gets a good recognition rate.

摘要： 主动形状模型（ASM）是面部特征定位、人脸识别和表情识别等模式识别领域中常用的一种方法。但受到初始情况、光照等诸多因素的影响，其性能会有所下降。研究了一种改进的主动形状模型，改进主要体现在两个方面：第一，首先用点轮廓检测算法（PCDM）检测到双眼的位置，为ASM中的点分布模型粗略地定位好初始位置；第二，从ASM原始的思想出发，充分挖掘标定点之间的联系，提出一种构建局部纹理模型的新方法。在JAFFE人脸数据库中进行验证，结果表明，改进ASM方法提高了搜索速度与特征点定位的精度。最终构造神经网络分类器进行人脸表情识别实验，得到了较好的识别率。