How to get the angle of correction in ORB detection OpenCV ++?

Question

// Find homography

h = findHomography( points1, points2, RANSAC );

// Use homography to warp image

warpPerspective(im1, im1Reg, h, im2.size());

I see here that the output image is warped but I wanted to know by how much the angle is changed with respect to the input image?

Answer 1

Hi please have a look at the documentation of the API before using it. link

the variable h which is a 3x3 matrix has the transformation.

Answer 2

What angle?

Perspective changing would not be defined with a simple rotation. That angle you are looking for, exists in Euclidean (rigid) transformation which preserves the euclidean distance between every pair of points.