Crop black edges with OpenCV

Question

I think it should be a very simple problem, but I cannot find a solution or an effective keyword for search.

I just have this image.

Answer 1

I thought this answer is much more succinct:

def crop(image):
    y_nonzero, x_nonzero, _ = np.nonzero(image)
    return image[np.min(y_nonzero):np.max(y_nonzero), np.min(x_nonzero):np.max(x_nonzero)]