Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/skimage/io/tests/test_histograms.py

@@ -0,0 +1,25 @@
+import numpy as np
+from skimage.io._plugins._histograms import histograms
+
+from skimage._shared.testing import assert_array_equal, assert_equal, TestCase
+
+
+class TestHistogram(TestCase):
+    def test_basic(self):
+        img = np.ones((50, 50, 3), dtype=np.uint8)
+        r, g, b, v = histograms(img, 255)
+
+        for band in (r, g, b, v):
+            yield assert_equal, band.sum(), 50 * 50
+
+    def test_counts(self):
+        channel = np.arange(255).reshape(51, 5)
+        img = np.empty((51, 5, 3), dtype='uint8')
+        img[:, :, 0] = channel
+        img[:, :, 1] = channel
+        img[:, :, 2] = channel
+        r, g, b, v = histograms(img, 255)
+        assert_array_equal(r, g)
+        assert_array_equal(r, b)
+        assert_array_equal(r, v)
+        assert_array_equal(r, np.ones(255))