review segmentation utils

[miguelgfierro]

def test_apply_mask_to_image(test_image):
    img = cv2.imread(test_image["lenna"])
    mask = cv2.imread(test_image["lenna_mask"], 0)
    masked = apply_mask_to_image(img, mask)

    assert np.count_nonzero(masked == 0) == 416754
    assert np.count_nonzero(masked != 0) == 369678

416754 and 369678 is too big for a mask, this looks a 3 channel matrix

[miguelgfierro]

def test_grabcut_mask(test_image):
    img = cv2.imread(test_image["lenna"])
    mask = cv2.imread(test_image["lenna_mask"], 0)
    img_result, mask = grabcut_mask(img, mask, iterations=1)

    assert np.count_nonzero(img_result == 0) == 416754
    assert np.count_nonzero(img_result != 0) == 369678
    assert np.count_nonzero(mask == 0) == 138918
    assert np.count_nonzero(mask == 255) == 123226

grabcut returns a mask between 0 and 1, instead of 0 and 255