Getting the projection matrix which can transform 3d points to 2d points in an image as done by cv2.projectPoints function in opencv
<p>The opencv function cv2.projectPoints() takes 3d points, rotation vector, translation vector, camera matrix and distortion coefficients and aspect ratio and generate the 2d projection of the 3d point in the image plane. Is there some way to get the full projection matrix which does the same to any 3d point so that i can do the projection without using the projectPoints fucntion</p>