Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/skimage/segmentation/tests/test_quickshift.py

@@ -0,0 +1,49 @@
+import numpy as np
+from skimage.segmentation import quickshift
+
+from skimage._shared.testing import (assert_greater, test_parallel,
+                                     assert_equal, assert_array_equal)
+
+
+@test_parallel()
+def test_grey():
+    rnd = np.random.RandomState(0)
+    img = np.zeros((20, 21))
+    img[:10, 10:] = 0.2
+    img[10:, :10] = 0.4
+    img[10:, 10:] = 0.6
+    img += 0.1 * rnd.normal(size=img.shape)
+    seg = quickshift(img, kernel_size=2, max_dist=3, random_seed=0,
+                     convert2lab=False, sigma=0)
+    # we expect 4 segments:
+    assert_equal(len(np.unique(seg)), 4)
+    # that mostly respect the 4 regions:
+    for i in range(4):
+        hist = np.histogram(img[seg == i], bins=[0, 0.1, 0.3, 0.5, 1])[0]
+        assert_greater(hist[i], 20)
+
+
+def test_color():
+    rnd = np.random.RandomState(0)
+    img = np.zeros((20, 21, 3))
+    img[:10, :10, 0] = 1
+    img[10:, :10, 1] = 1
+    img[10:, 10:, 2] = 1
+    img += 0.01 * rnd.normal(size=img.shape)
+    img[img > 1] = 1
+    img[img < 0] = 0
+    seg = quickshift(img, random_seed=0, max_dist=30, kernel_size=10, sigma=0)
+    # we expect 4 segments:
+    assert_equal(len(np.unique(seg)), 4)
+    assert_array_equal(seg[:10, :10], 1)
+    assert_array_equal(seg[10:, :10], 2)
+    assert_array_equal(seg[:10, 10:], 0)
+    assert_array_equal(seg[10:, 10:], 3)
+
+    seg2 = quickshift(img, kernel_size=1, max_dist=2, random_seed=0,
+                      convert2lab=False, sigma=0)
+    # very oversegmented:
+    assert_equal(len(np.unique(seg2)), 7)
+    # still don't cross lines
+    assert (seg2[9, :] != seg2[10, :]).all()
+    assert (seg2[:, 9] != seg2[:, 10]).all()