1. A method for rectifying an image, comprising: obtaining, by a computing device, an original stereo image pair; parallelizing, by the computing device, epipolar lines corresponding to the original stereo image pair to obtain a first transformed stereo image pair; and collinearizing, by the computing device, epipolar lines corresponding to the first transformed stereo image pair to obtain a second transformed stereo image pair, wherein obtaining of the original stereo image pair further comprises creating a stereo image point pair set by the computing device comprises: obtaining two angular point sets through angular point extraction; establishing mapping between angular points in the two angular point sets through feature matching, and creating the stereo image point pair set comprising two corresponding angular points.