def test_can_init_image_later(self):
algorithm = LiveWireSegmentation(self.test_image)
algorithm_post = LiveWireSegmentation()
algorithm_post.image = self.test_image
self.assertDictEqual(algorithm.G, algorithm_post.G,
'Post-initialization failed')
def test_can_read_threshold_parameter(self):
algorithm_with_thresholding = LiveWireSegmentation(
self.test_image, threshold_gradient_image=True)
algorithm_without_thresholding = LiveWireSegmentation(
self.test_image, threshold_gradient_image=False)
self.assertNotEqual(
np.linalg.norm(algorithm_with_thresholding.edges),
np.linalg.norm(algorithm_without_thresholding.edges),
'Gradient image with and without thresholding are the same')
def test_compute_shortest_path(self):
from_ = (0, 0)
to_ = (1, 1)
algorithm = LiveWireSegmentation(self.test_image)
path = algorithm.compute_shortest_path(from_, to_, length_penalty=0.0)
self.assertListEqual(path, [(0, 0), (0, 1), (1, 1)],
"Optimal path is not as expected")
def test_compute_shortest_path(self):
from_ = (0, 0)
to_ = (1, 1)
path_standalone = compute_shortest_path(self.test_image, from_, to_)
algorithm = LiveWireSegmentation(self.test_image)
path_class = algorithm.compute_shortest_path(from_,
to_,
length_penalty=0.0)
self.assertListEqual(path_standalone, path_class,
"Optimal path is not as expected")
def test_length_penalty_changes_result(self):
shape = self.test_image.shape
from_ = (shape[0] / 4, shape[1] / 4)
to_ = (shape[0] / 2, shape[1] / 2)
algorithm = LiveWireSegmentation(self.test_image)
path1 = algorithm.compute_shortest_path(from_, to_)
path2 = algorithm.compute_shortest_path(from_,
to_,
length_penalty=100.0)
self.assertNotEqual(
len(path1), len(path2),
'Length penalty has had no effect on optimal path')
def test_computes_graph_only_once(self):
from_ = (0, 0)
to_ = (1, 1)
algorithm = LiveWireSegmentation(self.test_image)
first_id = id(algorithm.G)
path = algorithm.compute_shortest_path(from_, to_)
prev_id = id(algorithm.G)
from_ = (10, 10)
to_ = (11, 11)
path = algorithm.compute_shortest_path(from_, to_)
cur_id = id(algorithm.G)
self.assertEqual(cur_id, prev_id,
'Graph was recomputed even though not requested')
self.assertEqual(first_id, prev_id,
'Graph was recomputed even though not requested')