[Python] rectifyPoint is broken since OpenCV 2 Python API change

[bsubei]

Just realized the Python rectifyPoint() method (in PinholeCameraModel inside image_geometry package) is broken, probably since the OpenCV 2 Python API change in this commit.

It seems the cv2.undistortPoints() function in Python (OpenCV 2 API) behaves differently than in OpenCV 1 (they don't document it apparently). Possible solution: the input argument src has to be a 3d array (?).

Just uncomment this line in the test and run it, and you will see it crash and give this error:

OpenCV Error: Assertion failed (src.isContinuous() && (src.depth() == CV_32F || src.depth() == CV_64F) && ((src.rows == 1 && src.channels() == 2) || src.cols*src.channels() == 2)) in undistortPoints, file /build/buildd/opencv-2.4.8+dfsg1/modules/imgproc/src/undistort.cpp, line 394
test_monocular ... ERROR!
ERROR: /build/buildd/opencv-2.4.8+dfsg1/modules/imgproc/src/undistort.cpp:394: error: (-215) src.isContinuous() && (src.depth() == CV_32F || src.depth() == CV_64F) && ((src.rows == 1 && src.channels() == 2) || src.cols*src.channels() == 2) in function undistortPoints

[bsubei]

I noticed I can get past this specific error if I comment out line 102, but then I face another error:

cv2.error: /build/buildd/opencv-2.4.8+dfsg1/modules/imgproc/src/undistort.cpp:279: error: (-215) CV_IS_MAT(_src) && CV_IS_MAT(_dst) && (_src->rows == 1 || _src->cols == 1) && (_dst->rows == 1 || _dst->cols == 1) && _src->cols + _src->rows - 1 == _dst->rows + _dst->cols - 1 && (CV_MAT_TYPE(_src->type) == CV_32FC2 || CV_MAT_TYPE(_src->type) == CV_64FC2) && (CV_MAT_TYPE(_dst->type) == CV_32FC2 || CV_MAT_TYPE(_dst->type) == CV_64FC2) in function cvUndistortPoints

Notice this error is inside cvUndistortPoints, which is called by undistortPoints (the previous error), so it seems like the above-mentioned fix is at least fixing part of the problem (or is progress towards one).

[bsubei]

Also, since the function signature (opencv 2) has changed to:
undistortPoints(src, cameraMatrix, distCoeffs[, dst[, R[, P]]]) -> dst , line 104 has to change to:
dst = cv2.undistortPoints(src, self.K, self.D, self.R, self.P)

[bsubei]

The cvUndistortPoints source code, where the assertion error is, for reference.

[bsubei]

found the solution! Will submit pull request soon.