OpenCV NoneType object has no attribute shape

Question

I  am working on Raspberry Pi with OpenCV and I was trying out a tutorial. But I am facing an error when I compile it.

This is the error: 

'NoneType' object has no attribute 'shape'.

This is the tutorial I am trying out: http://www.pyimagesearch.com/2015/09/14/ball-tracking-with-opencv/.

Can someone help me solve this?

Answer 1

To solve this just add assert after loading the image/frame. 

For image:

image = cv2.imread('myimage.png')
assert not isinstance(image,type(None)), 'image not found'

For video:

cap = cv2.VideoCapture(0)

    while(cap.isOpened()):

        # Capture frame-by-frame
        ret, frame = cap.read()
        if ret:

I hope this helps you.