I got rvec and tvec from the estimating pose function. Then formed a 4x4 matrix with use of Rodrigues(rvec) and tvec 4x4 = [[ rvec rvec rvec tvecx] [ rvec rvec rvec tvecy] [ rvec rvec rvec tvecz] [ 0 0 0 1]]. Correct me if I am wrong and don't know how to proceed further.