SIFT特征提取特征匹配

代码说明：

MATLAB实现图像的SIFT特征提取,不同视角下的特征匹配 FUNCTIONS The implementation consists of the following functions. They are organized in the folders based on the functionality.  These functions are self-contained and can be utilized independently.  do_gaussian: generate Gaussian scale space of input image do_diffofg: generate Difference of Gaussian (DoG) scale space  do_localmax: select local extrema as the potential keypoints do_extrefine: refine the keypoints by discarding the ones with low contrast and along an edge do_orientation: compute the orientation of a support region of keypoint do_descriptor: compute the descriptor of a keypoint based on image gradients.  do_match: match two images based on the nearest neighbor principle and spatial consistency. do_sift: generate the SIFT descriptors for a given input image. It basically executes all the functions above.