def _define_kernel(shape, size, dtype):
"""Build a kernel to apply a filter on images.
Parameters
----------
shape : str
Shape of the kernel used to compute the filter ('diamond', 'disk',
'rectangle' or 'square').
size : int, Tuple(int) or List(int)
The size of the kernel:
- For the rectangle we expect two values (width, height).
- For the square one value (width).
- For the disk and the diamond one value (radius).
dtype : type
Dtype used for the kernel (the same as the image).
Returns
-------
kernel : skimage.morphology.selem object
Kernel to use with a skimage filter.
"""
# build the kernel
if shape == "diamond":
kernel = diamond(size, dtype=dtype)
elif shape == "disk":
kernel = disk(size, dtype=dtype)
elif shape == "rectangle" and isinstance(size, tuple):
kernel = rectangle(size[0], size[1], dtype=dtype)
elif shape == "square":
kernel = square(size, dtype=dtype)
else:
raise ValueError("Kernel definition is wrong.")
return kernel
def _get_border(self, a):
pic_border = np.pad(np.zeros(tuple(map(lambda x: x - 2, a.shape))),
1,
'constant',
constant_values=1)
inner = binary_erosion(a, selem=square(3))
inner_without_pic_border = np.logical_and(inner,
np.logical_not(pic_border))
return np.logical_and(a, np.logical_not(inner_without_pic_border))
def setUp(self):
self.black_pixel = 255 * np.ones((4, 4), dtype=np.uint8)
self.black_pixel[1, 1] = 0
self.white_pixel = 255 - self.black_pixel
self.selems = [
selem.square(2),
selem.rectangle(2, 2),
selem.rectangle(2, 1),
selem.rectangle(1, 2)
]
def _define_kernel(shape, size, dtype):
"""Build a kernel to apply a filter on images.
Parameters
----------
shape : str
Shape of the kernel used to compute the filter (`diamond`, `disk`,
`rectangle` or `square`).
size : int, Tuple(int) or List(int)
The size of the kernel:
- For the rectangle we expect two values (`height`, `width`).
- For the square one value (`width`).
- For the disk and the diamond one value (`radius`).
dtype : type
Dtype used for the kernel (the same as the image).
Returns
-------
kernel : skimage.morphology.selem object
Kernel to use with a skimage filter.
"""
# build the kernel
if shape == "diamond":
kernel = diamond(size, dtype=dtype)
elif shape == "disk":
kernel = disk(size, dtype=dtype)
elif shape == "rectangle" and isinstance(size, (tuple, list)):
kernel = rectangle(size[0], size[1], dtype=dtype)
elif shape == "square":
kernel = square(size, dtype=dtype)
else:
raise ValueError("Kernel definition is wrong. Shape of the kernel "
"should be 'diamond', 'disk', 'rectangle' or "
"'square'. Not {0}.".format(shape))
return kernel
def test_binary_opening():
strel = selem.square(3)
binary_res = binary.binary_opening(bw_img, strel)
grey_res = img_as_bool(grey.opening(bw_img, strel))
testing.assert_array_equal(binary_res, grey_res)
def test_non_square_image():
strel = selem.square(3)
binary_res = binary.binary_erosion(bw_img[:100, :200], strel)
grey_res = img_as_bool(grey.erosion(bw_img[:100, :200], strel))
testing.assert_array_equal(binary_res, grey_res)
def test_binary_opening():
strel = selem.square(3)
binary_res = binary.binary_opening(bw_img, strel)
gray_res = img_as_bool(gray.opening(bw_img, strel))
testing.assert_array_equal(binary_res, gray_res)
def test_non_square_image():
strel = selem.square(3)
binary_res = binary.binary_erosion(bw_img[:100, :200], strel)
gray_res = img_as_bool(gray.erosion(bw_img[:100, :200], strel))
testing.assert_array_equal(binary_res, gray_res)
def test_binary_closing():
strel = selem.square(3)
binary_res = binary.binary_closing(bw_lena, strel)
grey_res = img_as_bool(grey.closing(bw_lena, strel))
testing.assert_array_equal(binary_res, grey_res)
def test_square_selem(self):
for k in range(0, 5):
actual_mask = selem.square(k)
expected_mask = np.ones((k, k), dtype="uint8")
assert_equal(expected_mask, actual_mask)
def test_binary_dilation():
strel = selem.square(3)
binary_res = binary.binary_dilation(bw_img, strel)
grey_res = img_as_bool(grey.dilation(bw_img, strel))
testing.assert_array_equal(binary_res, grey_res)
def test_square_selem(self):
"""Test square structuring elements"""
for k in range(0, 5):
actual_mask = selem.square(k)
expected_mask = np.ones((k, k), dtype='uint8')
assert_equal(expected_mask, actual_mask)
def test_square_selem(self):
"""Test square structuring elements"""
for k in range(0, 5):
actual_mask = selem.square(k)
expected_mask = np.ones((k, k), dtype='uint8')
assert_equal(expected_mask, actual_mask)
def test_binary_opening():
strel = selem.square(3)
binary_res = binary.binary_opening(bw_img, strel)
with expected_warnings(['precision loss']):
grey_res = img_as_bool(grey.opening(bw_img, strel))
testing.assert_array_equal(binary_res, grey_res)
def test_non_square_image():
strel = selem.square(3)
binary_res = binary.binary_erosion(bw_img[:100, :200], strel)
with expected_warnings(['precision loss']):
grey_res = img_as_bool(grey.erosion(bw_img[:100, :200], strel))
testing.assert_array_equal(binary_res, grey_res)
def setUp(self):
self.black_pixel = 255 * np.ones((4, 4), dtype=np.uint8)
self.black_pixel[1, 1] = 0
self.white_pixel = 255 - self.black_pixel
self.selems = [selem.square(2), selem.rectangle(2, 2),
selem.rectangle(2, 1), selem.rectangle(1, 2)]
def test_binary_dilation():
strel = selem.square(3)
binary_res = binary.binary_dilation(bw_lena, strel)
grey_res = img_as_bool(grey.dilation(bw_lena, strel))
testing.assert_array_equal(binary_res, grey_res)
def test_binary_opening():
strel = selem.square(3)
binary_res = binary.binary_opening(bw_lena, strel)
grey_res = grey.opening(bw_lena, strel)
testing.assert_array_equal(binary_res, grey_res)