Compute overlap for pair of keypoints

ovrl = cv.KeyPointsFilter.overlap(kp1, kp2)

Input

• kp1 First keypoint.
• kp2 Second keypoint.

Output

• ovrl Overlap is the ratio between area of keypoint regions' intersection and area of keypoint regions' union (considering keypoint region as circle). If they don't overlap, we get zero. If they coincide at same location with same size, we get 1.