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scikit-image/skimage/feature/tests/test_glcm.py
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2011-11-22 11:48:51 +00:00

145 lines
6.2 KiB
Python

import numpy as np
from skimage.feature import greycomatrix, greycoprops
class TestGLCM():
def setup(self):
self.image = np.array([[0, 0, 1, 1],
[0, 0, 1, 1],
[0, 2, 2, 2],
[2, 2, 3, 3]], dtype=np.uint8)
def test_output_angles(self):
result = greycomatrix(self.image, [1], [0, np.pi / 2], 4)
assert result.shape == (4, 4, 1, 2)
expected1 = np.array([[2, 2, 1, 0],
[0, 2, 0, 0],
[0, 0, 3, 1],
[0, 0, 0, 1]], dtype=np.uint32)
np.testing.assert_array_equal(result[:, :, 0, 0], expected1)
expected2 = np.array([[3, 0, 2, 0],
[0, 2, 2, 0],
[0, 0, 1, 2],
[0, 0, 0, 0]], dtype=np.uint32)
np.testing.assert_array_equal(result[:, :, 0, 1], expected2)
def test_output_symmetric_1(self):
result = greycomatrix(self.image, [1], [np.pi / 2], 4,
symmetric=True)
assert result.shape == (4, 4, 1, 1)
expected = np.array([[6, 0, 2, 0],
[0, 4, 2, 0],
[2, 2, 2, 2],
[0, 0, 2, 0]], dtype=np.uint32)
np.testing.assert_array_equal(result[:, :, 0, 0], expected)
def test_output_distance(self):
im = np.array([[0, 0, 0, 0],
[1, 0, 0, 1],
[2, 0, 0, 2],
[3, 0, 0, 3]], dtype=np.uint8)
result = greycomatrix(im, [3], [0], 4, symmetric=False)
expected = np.array([[1, 0, 0, 0],
[0, 1, 0, 0],
[0, 0, 1, 0],
[0, 0, 0, 1]], dtype=np.uint32)
np.testing.assert_array_equal(result[:, :, 0, 0], expected)
def test_output_combo(self):
im = np.array([[0],
[1],
[2],
[3]], dtype=np.uint8)
result = greycomatrix(im, [1, 2], [0, np.pi / 2], 4)
assert result.shape == (4, 4, 2, 2)
z = np.zeros((4, 4), dtype=np.uint32)
e1 = np.array([[0, 1, 0, 0],
[0, 0, 1, 0],
[0, 0, 0, 1],
[0, 0, 0, 0]], dtype=np.uint32)
e2 = np.array([[0, 0, 1, 0],
[0, 0, 0, 1],
[0, 0, 0, 0],
[0, 0, 0, 0]], dtype=np.uint32)
np.testing.assert_array_equal(result[:, :, 0, 0], z)
np.testing.assert_array_equal(result[:, :, 1, 0], z)
np.testing.assert_array_equal(result[:, :, 0, 1], e1)
np.testing.assert_array_equal(result[:, :, 1, 1], e2)
def test_output_empty(self):
result = greycomatrix(self.image, [10], [0], 4)
np.testing.assert_array_equal(result[:, :, 0, 0],
np.zeros((4, 4), dtype=np.uint32))
result = greycomatrix(self.image, [10], [0], 4, normed=True)
np.testing.assert_array_equal(result[:, :, 0, 0],
np.zeros((4, 4), dtype=np.uint32))
def test_normed_symmetric(self):
result = greycomatrix(self.image, [1, 2, 3],
[0, np.pi / 2, np.pi], 4,
normed=True, symmetric=True)
for d in range(result.shape[2]):
for a in range(result.shape[3]):
np.testing.assert_almost_equal(result[:, :, d, a].sum(),
1.0)
np.testing.assert_array_equal(result[:, :, d, a],
result[:, :, d, a].transpose())
def test_contrast(self):
result = greycomatrix(self.image, [1, 2], [0], 4,
normed=True, symmetric=True)
result = np.round(result, 3)
contrast = greycoprops(result, 'contrast')
np.testing.assert_almost_equal(contrast[0, 0], 0.586)
def test_dissimilarity(self):
result = greycomatrix(self.image, [1], [0, np.pi / 2], 4,
normed=True, symmetric=True)
result = np.round(result, 3)
dissimilarity = greycoprops(result, 'dissimilarity')
np.testing.assert_almost_equal(dissimilarity[0, 0], 0.418)
def test_dissimilarity_2(self):
result = greycomatrix(self.image, [1, 3], [np.pi/2], 4,
normed=True, symmetric=True)
result = np.round(result, 3)
dissimilarity = greycoprops(result, 'dissimilarity')[0, 0]
np.testing.assert_almost_equal(dissimilarity, 0.664)
def test_invalid_property(self):
result = greycomatrix(self.image, [1], [0], 4)
np.testing.assert_raises(ValueError, greycoprops,
result, 'ABC')
def test_homogeneity(self):
result = greycomatrix(self.image, [1], [0, 6], 4, normed=True,
symmetric=True)
homogeneity = greycoprops(result, 'homogeneity')[0, 0]
np.testing.assert_almost_equal(homogeneity, 0.80833333)
def test_energy(self):
result = greycomatrix(self.image, [1], [0, 4], 4, normed=True,
symmetric=True)
energy = greycoprops(result, 'energy')[0, 0]
np.testing.assert_almost_equal(energy, 0.38188131)
def test_correlation(self):
result = greycomatrix(self.image, [1, 2], [0], 4, normed=True,
symmetric=True)
energy = greycoprops(result, 'correlation')
np.testing.assert_almost_equal(energy[0, 0], 0.71953255)
np.testing.assert_almost_equal(energy[1, 0], 0.41176470)
def test_uniform_properties(self):
im = np.ones((4, 4), dtype=np.uint8)
result = greycomatrix(im, [1, 2, 8], [0, np.pi / 2], 4, normed=True,
symmetric=True)
for prop in ['contrast', 'dissimilarity', 'homogeneity',
'energy', 'correlation', 'ASM']:
greycoprops(result, prop)
if __name__ == '__main__':
np.testing.run_module_suite()