Add test for LineProfiler tool

skimage/viewer/tests/test_viewer.py

@@ -0,0 +1,43 @@
+import skimage.data as data
+from skimage.viewer import ImageViewer
+from numpy.testing import assert_equal, assert_allclose
+
+
+def setup_line_profile(image):
+    from skimage.viewer.plugins.lineprofile import LineProfile
+    viewer = ImageViewer(image)
+    plugin = LineProfile()
+    viewer += plugin
+    return plugin
+
+
+def test_line_profile():
+    """ Test a line profile using an ndim=2 image"""
+    plugin = setup_line_profile(data.camera())
+    line_image, scan_data = plugin.output()
+    for inp in [line_image.nonzero()[0].size,
+                line_image.sum() / line_image.max(),
+                scan_data.size]:
+        assert_equal(inp, 172)
+    assert_equal(line_image.shape, (512, 512))
+    assert_equal(scan_data.max(), 234.0)
+    assert_allclose(scan_data.mean(), 71.726744186046517)
+
+
+def test_line_profile_rgb():
+    """ Test a line profile using an ndim=3 image"""
+    plugin = setup_line_profile(data.chelsea())
+    for i in range(6):
+        plugin.line_tool._thicken_scan_line()
+    line_image, scan_data = plugin.output()
+    assert_equal(line_image[line_image == 128].size, 906)
+    assert_equal(line_image[line_image == 255].size, 151)
+    assert_equal(line_image.shape, (300, 451))
+    assert_equal(scan_data.shape, (151, 3))
+    assert_allclose(scan_data.max(), 196.85714285714286)
+    assert_allclose(scan_data.mean(), 111.17029328287606)
+
+
+if __name__ == "__main__":
+    from numpy.testing import run_module_suite
+    run_module_suite()