这是一个SIFT的特征提取程序，我已经试验过，可以找到特征点并且声称特征点描述子。代码结构很清晰，简单易懂，非常适合初学者的学习。-This is a SIFT feature extraction procedures, I' ve been tested, you can find the feature points and claimed that the descr iption of the feature point. Code structure is very clear