# Revision history [back]

### Python-tutorials mistakes

I've seen the camera python-opencv pose estimation tutorial the following use in cv2.line:

    img = cv2.line(img, corner, tuple(imgpts[1].ravel()), (0,255,0), 5)


which didn't work, because cv2.line returns None. It worked fine when I just removed the assigning.

In addition, I think similar problem in the same tutorial:

corners2 = cv2.cornerSubPix(gray,corners,(11,11),(-1,-1),criteria)


which gives None according to the API. I guess it just suppose to update corners.

I'm really new to OpenCV, so I am not sure but I think those are mistakes (or old version) which need to be fixed, especially in a beginner tutorials.

Can I fix them without working with push/pull through git?

 2 retagged berak 28515 ●4 ●75 ●286

### Python-tutorials mistakes

I've seen the camera python-opencv pose estimation tutorial the following use in cv2.line:

    img = cv2.line(img, corner, tuple(imgpts[1].ravel()), (0,255,0), 5)


which didn't work, because cv2.line returns None. It worked fine when I just removed the assigning.

In addition, I think similar problem in the same tutorial:

corners2 = cv2.cornerSubPix(gray,corners,(11,11),(-1,-1),criteria)


which gives None according to the API. I guess it just suppose to update corners.

I'm really new to OpenCV, so I am not sure but I think those are mistakes (or old version) which need to be fixed, especially in a beginner tutorials.

Can I fix them without working with push/pull through git?