def test_3d_energy_decrease():
a_black = cp.zeros((5, 5, 5)).astype(np.uint8)
a_black[2, 2, 2] = 255
a_white = invert(a_black)
assert_array_less(meijering(a_black, black_ridges=True).std(),
a_black.std())
assert_array_less(meijering(a_white, black_ridges=False).std(),
a_white.std())
assert_array_less(sato(a_black, black_ridges=True, mode='reflect').std(),
a_black.std())
assert_array_less(sato(a_white, black_ridges=False, mode='reflect').std(),
a_white.std())
assert_array_less(frangi(a_black, black_ridges=True).std(),
a_black.std())
assert_array_less(frangi(a_white, black_ridges=False).std(),
a_white.std())
assert_array_less(hessian(a_black, black_ridges=True,
mode='reflect').std(), a_black.std())
assert_array_less(hessian(a_white, black_ridges=False,
mode='reflect').std(), a_white.std())
def test_3d_linearity():
a_black = cp.ones((3, 3, 3)).astype(np.uint8)
a_white = invert(a_black)
assert_allclose(meijering(1 * a_black, black_ridges=True),
meijering(10 * a_black, black_ridges=True), atol=1e-3)
assert_allclose(meijering(1 * a_white, black_ridges=False),
meijering(10 * a_white, black_ridges=False), atol=1e-3)
assert_allclose(sato(1 * a_black, black_ridges=True, mode='reflect'),
sato(10 * a_black, black_ridges=True, mode='reflect'),
atol=1e-3)
assert_allclose(sato(1 * a_white, black_ridges=False, mode='reflect'),
sato(10 * a_white, black_ridges=False, mode='reflect'),
atol=1e-3)
assert_allclose(frangi(1 * a_black, black_ridges=True),
frangi(10 * a_black, black_ridges=True), atol=1e-3)
assert_allclose(frangi(1 * a_white, black_ridges=False),
frangi(10 * a_white, black_ridges=False), atol=1e-3)
assert_allclose(hessian(1 * a_black, black_ridges=True, mode='reflect'),
hessian(10 * a_black, black_ridges=True, mode='reflect'),
atol=1e-3)
assert_allclose(hessian(1 * a_white, black_ridges=False, mode='reflect'),
hessian(10 * a_white, black_ridges=False, mode='reflect'),
atol=1e-3)
def test_invert_bool():
dtype = 'bool'
image = cp.zeros((3, 3), dtype=dtype)
upper_dtype_limit = dtype_limits(image, clip_negative=False)[1]
image[1, :] = upper_dtype_limit
expected = cp.zeros((3, 3), dtype=dtype) + upper_dtype_limit
expected[1, :] = 0
result = invert(image)
assert_array_equal(expected, result)
def test_invert_float64_unsigned():
dtype = 'float64'
image = cp.zeros((3, 3), dtype=dtype)
lower_dtype_limit, upper_dtype_limit = \
dtype_limits(image, clip_negative=True)
image[2, :] = upper_dtype_limit
expected = cp.zeros((3, 3), dtype=dtype)
expected[0, :] = upper_dtype_limit
expected[1, :] = upper_dtype_limit
result = invert(image)
assert_array_equal(expected, result)
def test_invert_int8():
dtype = 'int8'
image = cp.zeros((3, 3), dtype=dtype)
lower_dtype_limit, upper_dtype_limit = \
dtype_limits(image, clip_negative=False)
image[1, :] = lower_dtype_limit
image[2, :] = upper_dtype_limit
expected = cp.zeros((3, 3), dtype=dtype)
expected[2, :] = lower_dtype_limit
expected[1, :] = upper_dtype_limit
expected[0, :] = -1
result = invert(image)
assert_array_equal(expected, result)
def test_2d_cropped_camera_image():
a_black = crop(cp.array(camera()), ((200, 212), (100, 312)))
a_white = invert(a_black)
zeros = cp.zeros((100, 100))
ones = cp.ones((100, 100))
assert_allclose(meijering(a_black, black_ridges=True),
meijering(a_white, black_ridges=False))
assert_allclose(sato(a_black, black_ridges=True, mode='mirror'),
sato(a_white, black_ridges=False, mode='mirror'))
assert_allclose(frangi(a_black, black_ridges=True), zeros, atol=1e-3)
assert_allclose(frangi(a_white, black_ridges=False), zeros, atol=1e-3)
assert_allclose(hessian(a_black, black_ridges=True, mode='mirror'),
ones, atol=1 - 1e-7)
assert_allclose(hessian(a_white, black_ridges=False, mode='mirror'),
ones, atol=1 - 1e-7)
def test_2d_null_matrix():
a_black = cp.zeros((3, 3)).astype(cp.uint8)
a_white = invert(a_black)
zeros = cp.zeros((3, 3))
ones = cp.ones((3, 3))
assert_array_equal(meijering(a_black, black_ridges=True), zeros)
assert_array_equal(meijering(a_white, black_ridges=False), zeros)
assert_array_equal(sato(a_black, black_ridges=True, mode='reflect'),
zeros)
assert_array_equal(sato(a_white, black_ridges=False, mode='reflect'),
zeros)
assert_allclose(frangi(a_black, black_ridges=True), zeros, atol=1e-3)
assert_allclose(frangi(a_white, black_ridges=False), zeros, atol=1e-3)
assert_array_equal(hessian(a_black, black_ridges=False, mode='reflect'),
ones)
assert_array_equal(hessian(a_white, black_ridges=True, mode='reflect'),
ones)
def test_3d_cropped_camera_image():
a_black = crop(cp.asarray(camera()), ((200, 212), (100, 312)))
a_black = cp.dstack([a_black, a_black, a_black])
a_white = invert(a_black)
zeros = cp.zeros((100, 100, 3))
ones = cp.ones((100, 100, 3))
# TODO: determine why the following allclose checks occassionally fail
assert_allclose(meijering(a_black, black_ridges=True),
meijering(a_white, black_ridges=False))
assert_allclose(sato(a_black, black_ridges=True, mode='mirror'),
sato(a_white, black_ridges=False, mode='mirror'))
assert_allclose(frangi(a_black, black_ridges=True), zeros, atol=1e-3)
assert_allclose(frangi(a_white, black_ridges=False), zeros, atol=1e-3)
assert_allclose(hessian(a_black, black_ridges=True, mode='mirror'),
ones, atol=1 - 1e-7)
assert_allclose(hessian(a_white, black_ridges=False, mode='mirror'),
ones, atol=1 - 1e-7)
def test_invert_roundtrip():
for t, limits in dtype_range.items():
image = cp.array(limits, dtype=t)
expected = invert(invert(image))
assert_array_equal(image, expected)
