import numpy as np
from skimage import graph


def test_threshold_cut():

    img = np.zeros((100, 100, 3), dtype='uint8')
    img[:50, :50] = 255, 255, 255
    img[:50, 50:] = 254, 254, 254
    img[50:, :50] = 2, 2, 2
    img[50:, 50:] = 1, 1, 1

    labels = np.zeros((100, 100), dtype='uint8')
    labels[:50, :50] = 0
    labels[:50, 50:] = 1
    labels[50:, :50] = 2
    labels[50:, 50:] = 3

    rag = graph.rag_meancolor(img, labels)
    new_labels = graph.threshold_cut(labels, rag, 10)

    # Two labels
    assert new_labels.max() == 1