Add support for unsigned integer label images

skimage/measure/_regionprops.py

@@ -470,8 +470,6 @@ def regionprops(label_image, properties=None,
     >>> props[0].centroid # centroid of first labelled object
     >>> props[0]['centroid'] # centroid of first labelled object
     """
-    if not np.issubdtype(label_image.dtype, 'int'):
-        raise TypeError('Labelled image must be of integer dtype.')
 
     if properties is not None:
         warnings.warn('The ``properties`` argument is deprecated and is '

skimage/measure/tests/test_regionprops.py

@@ -28,7 +28,9 @@ def test_all_props():
         regions[prop]
 
 
-def test_unsupported_dtype():
+def test_dtype():
+    regionprops(np.zeros((10, 10), dtype=np.int))
+    regionprops(np.zeros((10, 10), dtype=np.uint))
     assert_raises(TypeError, regionprops, np.zeros((10, 10), dtype=np.double))