尺度不变特征转换是一种电脑视觉的算法用来侦测与描述影像中的局部性特征，它在空间尺度中寻找极值点，并提取出其位置、尺度、旋转不变量-SIFT is a computer vision algorithms to detect and describe the characteristics of the image in the locality, it is looking at the spatial scale of the extreme points, and extract its p