函数原型:edge = cv2.Canny(image, threshold1, threshold2[, edges[, apertureSize[, L2gradient ]]])
matrix m = cv2.estimateRigidTransform(prev_pts, curr_pts, fullAffine=False) #will only work with OpenCV
transformation matrix m = cv2.estimateRigidTransform(prev_pts, curr_pts, fullAffine=False) #will only work with OpenCV