How to find the rotation matrix with known points?

The corner points of a rectangle are given in 2D coordinates. I also know the real distance of the points and I have the camera matrix.

Now I want to find the rotation vector with respect to the camera, but without using the cv2.calibrateCamera() method with the chessboard corners.

related: python - How to find the rotation matrix with known points - Stack Overflow

look into how aruco does it. it does a type of solvePnP too but it can assume to be seeing the quad from one specific side of the plane and it knows the order of corners, so there’s no ambiguity around that axis either.

If you have the correspondences 3D object points <--> 2D points images (+ the camera intrinsic parameters), you can indeed use cv::solvePnP() to compute the rotation matrix and the translation vector from 4 pairs of correspondences.

I mean no need to have 6 points, the problem is solvable with 4 points.


That worked very well, thank you so much!