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pythonopencvarucopose

Solve PnP or Estimate Pose Single Markers: which is better?


I need a program to estimate the pose of an ArUco marker, and, as far as I know, I can code it with two different functions: cv2.solvePnp() or cv2.aruco.estimatePoseSingleMarker(). Which one is better? I read about them, and it seems easier to use cv2.aruco.estimatePoseSingleMarker(), but is it as accurate as cv2.solvePnP()? Thanks

I am a graduating student, and I need this information because I am doing a research with a teacher.


Solution

  • estimatePoseSingleMarkers no longer exists as of version 4.7. Here, I replaced the function for you using SolvePnP:

    def my_estimatePoseSingleMarkers(corners, marker_size, mtx, distortion):
        '''
        This will estimate the rvec and tvec for each of the marker corners detected by:
           corners, ids, rejectedImgPoints = detector.detectMarkers(image)
        corners - is an array of detected corners for each detected marker in the image
        marker_size - is the size of the detected markers
        mtx - is the camera matrix
        distortion - is the camera distortion matrix
        RETURN list of rvecs, tvecs, and trash (so that it corresponds to the old estimatePoseSingleMarkers())
        '''
        marker_points = np.array([[-marker_size / 2, marker_size / 2, 0],
                                  [marker_size / 2, marker_size / 2, 0],
                                  [marker_size / 2, -marker_size / 2, 0],
                                  [-marker_size / 2, -marker_size / 2, 0]], dtype=np.float32)
        trash = []
        rvecs = []
        tvecs = []
        
        for c in corners:
            nada, R, t = cv2.solvePnP(marker_points, c, mtx, distortion, False, cv2.SOLVEPNP_IPPE_SQUARE)
            rvecs.append(R)
            tvecs.append(t)
            trash.append(nada)
        return rvecs, tvecs, trash