def get_edges(img):
edge = np.empty(img.shape)
if len(img.shape) == 3:
for i in range(3):
edge[:, :, i] = imfilt.sobel(img[:, :, i])
else:
edge = imfilt.sobel(img)
edge = rescale_intensity(edge)
return edge
def test_convolution_upcast(self):
i, j = np.mgrid[-5:6, -5:6]
image = np.load(os.path.join(data_dir, 'lena_GRAY_U8.npy'))
result1 = F.sobel(image)
image = image.astype(float)
result2 = F.sobel(image)
assert_array_equal(result1, result2)
def test_convolution_upcast(self):
i, j = np.mgrid[-5:6, -5:6]
image = np.load(os.path.join(data_dir, 'lena_GRAY_U8.npy'))
result1 = F.sobel(image)
image = image.astype(float)
result2 = F.sobel(image)
assert_array_equal(result1, result2)
def test_01_02_vertical(self):
"""Sobel on a vertical edge should be a vertical line"""
i, j = np.mgrid[-5:6, -5:6]
image = (j >= 0).astype(float)
result = F.sobel(image)
j[np.abs(i) == 5] = 10000
assert (np.all(result[j == 0] == 1))
assert (np.all(result[np.abs(j) > 1] == 0))
def test_01_02_vertical(self):
"""Sobel on a vertical edge should be a vertical line"""
i, j = np.mgrid[-5:6, -5:6]
image = (j >= 0).astype(float)
result = F.sobel(image)
j[np.abs(i) == 5] = 10000
assert (np.all(result[j == 0] == 1))
assert (np.all(result[np.abs(j) > 1] == 0))
def test_01_01_horizontal(self):
"""Sobel on an edge should be a horizontal line"""
i, j = np.mgrid[-5:6, -5:6]
image = (i >= 0).astype(float)
result = F.sobel(image)
# Fudge the eroded points
i[np.abs(j) == 5] = 10000
assert (np.all(result[i == 0] == 1))
assert (np.all(result[np.abs(i) > 1] == 0))
def test_01_01_horizontal(self):
"""Sobel on an edge should be a horizontal line"""
i, j = np.mgrid[-5:6, -5:6]
image = (i >= 0).astype(float)
result = F.sobel(image)
# Fudge the eroded points
i[np.abs(j) == 5] = 10000
assert (np.all(result[i == 0] == 1))
assert (np.all(result[np.abs(i) > 1] == 0))
def test_00_01_mask(self):
"""Sobel on a masked array should be zero"""
np.random.seed(0)
result = F.sobel(np.random.uniform(size=(10, 10)),
np.zeros((10, 10), bool))
assert (np.all(result == 0))
def test_00_00_zeros(self):
"""Sobel on an array of all zeros"""
result = F.sobel(np.zeros((10, 10)), np.ones((10, 10), bool))
assert (np.all(result == 0))
def test_00_01_mask(self):
"""Sobel on a masked array should be zero"""
np.random.seed(0)
result = F.sobel(np.random.uniform(size=(10, 10)),
np.zeros((10, 10), bool))
assert (np.all(result == 0))
def test_00_00_zeros(self):
"""Sobel on an array of all zeros"""
result = F.sobel(np.zeros((10, 10)), np.ones((10, 10), bool))
assert (np.all(result == 0))