feat: support float16 for labeled images

automated_test.py

@@ -9,7 +9,7 @@
   np.uint8, np.uint16, np.uint32, np.uint64,
 ]
 
-TEST_TYPES = INT_TYPES + [ np.float32, np.float64 ]
+TEST_TYPES = INT_TYPES + [ np.float16, np.float32, np.float64 ]
 
 OUT_TYPES = [ np.uint16, np.uint32, np.uint64 ]
 
@@ -1006,6 +1006,11 @@ def test_continuous_ccl_diagonal(order, dtype, connectivity):
   labels[0,1] = 3
   labels[1,1] = 4
 
+  if dtype == np.float16:
+    with pytest.raises(TypeError) as e_info:
+      out = cc3d.connected_components(labels, delta=1, connectivity=connectivity)
+    return
+
   out = cc3d.connected_components(labels, delta=0, connectivity=connectivity)
   assert np.all(np.unique(labels) == [1,2,3,4])
 
@@ -1025,6 +1030,11 @@ def test_continuous_ccl_4_6(order, dtype, connectivity):
   out = cc3d.connected_components(labels, delta=0, connectivity=connectivity)
   assert np.all(np.unique(labels) == [1,2,3,4])
 
+  if dtype == np.float16:
+    with pytest.raises(TypeError) as e_info:
+      out = cc3d.connected_components(labels, delta=1, connectivity=connectivity)
+    return
+
   out = cc3d.connected_components(labels, delta=1, connectivity=connectivity)
   assert np.all(out == np.array([
     [1, 2],
@@ -1049,6 +1059,11 @@ def test_continuous_blocks(dtype, connectivity, order):
   )
   assert np.unique(out).size > 1000
 
+  if dtype == np.float16:
+    with pytest.raises(TypeError) as e_info:
+      out = cc3d.connected_components(img, delta=1, connectivity=connectivity)
+    return
+
   out = cc3d.connected_components(
     img, connectivity=connectivity, delta=1
   )

cc3d.pyx

@@ -222,7 +222,10 @@ def estimate_provisional_labels(data:np.ndarray) -> Tuple[int,int,int]:
         first_foreground_row, last_foreground_row
       )
     else:
-      raise TypeError("Type {} not currently supported.".format(dtype))
+      raise TypeError(
+        f"Type {dtype} is not currently supported. "
+        f"Supported: bool, int8, int16, int32, int64, uint8, uint16, uint32, uint64, float16, float32, float64"
+      )
   finally:
     if data.flags.owndata:
       data.setflags(write=writable)
@@ -312,6 +315,12 @@ def connected_components(
   if not data.flags.c_contiguous and not data.flags.f_contiguous:
     data = np.copy(data, order=order)
 
+  if data.dtype == np.float16:
+    if delta == 0:
+      data = data.view(np.uint16)
+    else:
+      raise TypeError("float16 is not supported for continuous images (delta != 0).")
+
   shape = list(data.shape)
 
   if order == 'C':
@@ -541,7 +550,10 @@ def connected_components(
           <uint64_t*>&out_labels64[0], N, periodic_boundary
         )
     else:
-      raise TypeError("Type {} not currently supported.".format(dtype))
+      raise TypeError(
+        f"Type {dtype} is not currently supported. "
+        f"Supported: bool, int8, int16, int32, int64, uint8, uint16, uint32, uint64, float16, float32, float64"
+      )
   finally:
     if data.flags.owndata:
       data.setflags(write=writable)