def test_threshold_minimum():
camera = skimage.img_as_ubyte(data.camera())
threshold = threshold_minimum(camera)
assert_equal(threshold, 76)
astronaut = skimage.img_as_ubyte(data.astronaut())
threshold = threshold_minimum(astronaut)
assert_equal(threshold, 114)
def test_threshold_minimum():
camera = skimage.img_as_ubyte(data.camera())
threshold = threshold_minimum(camera)
assert_equal(threshold, 76)
astronaut = skimage.img_as_ubyte(data.astronaut())
threshold = threshold_minimum(astronaut)
assert_equal(threshold, 114)
def test_threshold_minimum():
camera = util.img_as_ubyte(data.camera())
threshold = threshold_minimum(camera)
assert_equal(threshold, 85)
astronaut = util.img_as_ubyte(data.astronaut())
threshold = threshold_minimum(astronaut)
assert_equal(threshold, 114)
def test_threshold_minimum():
camera = skimage.img_as_ubyte(data.camera())
threshold = threshold_minimum(camera)
assert threshold == 76
threshold = threshold_minimum(camera, bias='max')
assert threshold == 77
astronaut = skimage.img_as_ubyte(data.astronaut())
threshold = threshold_minimum(astronaut)
assert threshold == 117
def test_threshold_minimum():
camera = skimage.img_as_ubyte(data.camera())
threshold = threshold_minimum(camera)
assert threshold == 76
threshold = threshold_minimum(camera, bias='max')
assert threshold == 77
astronaut = skimage.img_as_ubyte(data.astronaut())
threshold = threshold_minimum(astronaut)
assert threshold == 117
def test_threshold_minimum_synthetic():
img = np.arange(25 * 25, dtype=np.uint8).reshape((25, 25))
img[0:9, :] = 50
img[14:25, :] = 250
threshold = threshold_minimum(img, bias='min')
assert threshold == 93
threshold = threshold_minimum(img, bias='mid')
assert threshold == 159
threshold = threshold_minimum(img, bias='max')
assert threshold == 225
def test_threshold_minimum_synthetic():
img = np.arange(25*25, dtype=np.uint8).reshape((25, 25))
img[0:9, :] = 50
img[14:25, :] = 250
threshold = threshold_minimum(img, bias='min')
assert threshold == 93
threshold = threshold_minimum(img, bias='mid')
assert threshold == 159
threshold = threshold_minimum(img, bias='max')
assert threshold == 225
def test_threshold_minimum_synthetic():
img = np.arange(25*25, dtype=np.uint8).reshape((25, 25))
img[0:9, :] = 50
img[14:25, :] = 250
threshold = threshold_minimum(img)
assert_equal(threshold, 95)
def test_threshold_minimum_synthetic():
img = np.arange(25 * 25, dtype=np.uint8).reshape((25, 25))
img[0:9, :] = 50
img[14:25, :] = 250
threshold = threshold_minimum(img)
assert_equal(threshold, 95)
def test_threshold_minimum_failure():
img = np.zeros((16*16), dtype=np.uint8)
with pytest.raises(RuntimeError):
threshold_minimum(img)
def test_threshold_minimum_failure():
img = np.zeros((16 * 16), dtype=np.uint8)
with testing.raises(RuntimeError):
threshold_minimum(img)
def test_minimum(self):
with pytest.raises(RuntimeError):
threshold_minimum(self.image)
def test_threshold_minimum_counts():
camera = util.img_as_ubyte(data.camera())
counts, bin_centers = histogram(camera.ravel(), 256, source_range='image')
threshold = threshold_minimum(hist=counts)
assert_equal(threshold, 85)
def test_threshold_minimum_histogram():
camera = util.img_as_ubyte(data.camera())
hist = histogram(camera.ravel(), 256, source_range='image')
threshold = threshold_minimum(hist=hist)
assert_equal(threshold, 85)
The minimum algorithm takes a histogram of the image and smooths it
repeatedly until there are only two peaks in the histogram. Then it
finds the minimum value between the two peaks. After smoothing the
histogram, there can be multiple pixel values with the minimum histogram
count, so you can pick the 'min', 'mid', or 'max' of these values.
"""
import matplotlib.pyplot as plt
from skimage import data
from skimage.filters.thresholding import threshold_minimum
image = data.camera()
threshold = threshold_minimum(image, bias='min')
binarized = image > threshold
fig, axes = plt.subplots(nrows=2, figsize=(7, 8))
ax0, ax1 = axes
plt.gray()
ax0.imshow(image)
ax0.set_title('Original image')
ax1.imshow(binarized)
ax1.set_title('Result')
for ax in axes:
ax.axis('off')
def test_minimum(self):
with pytest.raises(RuntimeError):
threshold_minimum(self.image)
def test_threshold_minimum_deprecated_max_iter_kwarg():
camera = util.img_as_ubyte(data.camera())
hist = histogram(camera.ravel(), 256, source_range='image')
with expected_warnings(["`max_iter` is a deprecated argument"]):
threshold_minimum(hist=hist, max_iter=5000)
