1 | initial version |
Why not? Easy approach would be to get the keypoints from the both the image and section them into segments, to prevent false matching. You can start with 2x2 sections. Maybe 3x3 or 3x4 given how big is your image and expected aspect ratio. Now match corresponding section's keypoint based descriptor with each other. Play with the strictness of the matches. Now when you have the matches. Scale is easy to calculate in both direction X and Y, by comparing the distance between the matched keypoints in corresponding images.