眨眼检测，先用haar特征框定人脸，然后用camshift跟踪人脸，根据几何特征得到人眼的大概位置，然后根据直方图的变化检测眨眼-Blink detection, the first feature with the haar fr a med face, and then use camshift tracking human face, according to the geometric features are the approximate location of the human