Raise ValueError for unsupported dtypes. (#1316)

* Raise ValueError for unsupported dtypes.

* Add type and fix test.

* Update changelog.

* refactor.

* implement requested change.

Author: markbader

webknossos/Changelog.md

@@ -17,6 +17,7 @@ For upgrade instructions, please check the respective _Breaking Changes_ section
 ### Added
 
 ### Changed
+- When adding a layer, the used dtype is only valid if it is supported by webknossos. [#1316](https://github.com/scalableminds/webknossos-libs/pull/1316)
 
 ### Fixed
 - Fixed an issue that creates an Error when `add_mag()` was called just with a `chunk_shape`. [#1315](https://github.com/scalableminds/webknossos-libs/pull/1315)

webknossos/tests/dataset/test_dataset.py

@@ -24,6 +24,7 @@
     COLOR_CATEGORY,
     SEGMENTATION_CATEGORY,
     Dataset,
+    LayerCategoryType,
     RemoteDataset,
     View,
 )
@@ -1554,41 +1555,6 @@ def test_adding_layer_with_valid_dtype_per_layer() -> None:
         ds.add_layer(
             "color4", COLOR_CATEGORY, dtype_per_channel="uint8", num_channels=3
         )
-        ds.add_layer(
-            "seg1",
-            SEGMENTATION_CATEGORY,
-            dtype_per_channel="float",
-            num_channels=1,
-            largest_segment_id=100000,
-        )
-        ds.add_layer(
-            "seg2",
-            SEGMENTATION_CATEGORY,
-            dtype_per_channel=float,
-            num_channels=1,
-            largest_segment_id=100000,
-        )
-        ds.add_layer(
-            "seg3",
-            SEGMENTATION_CATEGORY,
-            dtype_per_channel=float,
-            num_channels=1,
-            largest_segment_id=100000,
-        )
-        ds.add_layer(
-            "seg4",
-            SEGMENTATION_CATEGORY,
-            dtype_per_channel="double",
-            num_channels=1,
-            largest_segment_id=100000,
-        )
-        ds.add_layer(
-            "seg5",
-            SEGMENTATION_CATEGORY,
-            dtype_per_channel="float",
-            num_channels=3,
-            largest_segment_id=100000,
-        )
 
         with open(
             ds_path / "datasource-properties.json",
@@ -1600,11 +1566,6 @@ def test_adding_layer_with_valid_dtype_per_layer() -> None:
             assert data["dataLayers"][1]["elementClass"] == "uint8"
             assert data["dataLayers"][2]["elementClass"] == "uint24"
             assert data["dataLayers"][3]["elementClass"] == "uint24"
-            assert data["dataLayers"][4]["elementClass"] == "float"
-            assert data["dataLayers"][5]["elementClass"] == "float"
-            assert data["dataLayers"][6]["elementClass"] == "float"
-            assert data["dataLayers"][7]["elementClass"] == "double"
-            assert data["dataLayers"][8]["elementClass"] == "float96"
 
         reopened_ds = Dataset.open(
             ds_path
@@ -1613,12 +1574,6 @@ def test_adding_layer_with_valid_dtype_per_layer() -> None:
         assert reopened_ds.get_layer("color2").dtype_per_layer == "uint8"
         assert reopened_ds.get_layer("color3").dtype_per_layer == "uint24"
         assert reopened_ds.get_layer("color4").dtype_per_layer == "uint24"
-        # Note that 'float' and 'double' are stored as 'float32' and 'float64'
-        assert reopened_ds.get_layer("seg1").dtype_per_layer == "float32"
-        assert reopened_ds.get_layer("seg2").dtype_per_layer == "float32"
-        assert reopened_ds.get_layer("seg3").dtype_per_layer == "float32"
-        assert reopened_ds.get_layer("seg4").dtype_per_layer == "float64"
-        assert reopened_ds.get_layer("seg5").dtype_per_layer == "float96"
 
         assure_exported_properties(ds)
 
@@ -3044,6 +2999,57 @@ def test_add_layer_like(data_format: DataFormat, output_path: Path) -> None:
     assure_exported_properties(ds)
 
 
+@pytest.mark.parametrize(
+    "dtype_per_channel,category,is_supported",
+    [
+        ("uint8", COLOR_CATEGORY, True),
+        ("uint16", COLOR_CATEGORY, True),
+        ("uint32", COLOR_CATEGORY, True),
+        ("uint64", COLOR_CATEGORY, False),
+        ("int8", COLOR_CATEGORY, True),
+        ("int16", COLOR_CATEGORY, True),
+        ("int32", COLOR_CATEGORY, True),
+        ("int64", COLOR_CATEGORY, False),
+        ("float32", COLOR_CATEGORY, True),
+        ("float64", COLOR_CATEGORY, False),
+        ("uint8", SEGMENTATION_CATEGORY, True),
+        ("uint16", SEGMENTATION_CATEGORY, True),
+        ("uint32", SEGMENTATION_CATEGORY, True),
+        ("uint64", SEGMENTATION_CATEGORY, True),
+        ("int8", SEGMENTATION_CATEGORY, True),
+        ("int16", SEGMENTATION_CATEGORY, True),
+        ("int32", SEGMENTATION_CATEGORY, True),
+        ("int64", SEGMENTATION_CATEGORY, True),
+        ("float32", SEGMENTATION_CATEGORY, False),
+        ("float64", SEGMENTATION_CATEGORY, False),
+    ],
+)
+def test_add_layer_dtype_per_channel(
+    dtype_per_channel: str, category: LayerCategoryType, is_supported: bool
+) -> None:
+    ds_path = prepare_dataset_path(
+        DataFormat.Zarr3, TESTOUTPUT_DIR, "dtype_per_channel"
+    )
+    ds = Dataset(ds_path, voxel_size=(1, 1, 1))
+    if is_supported:
+        layer = ds.add_layer(
+            "test_layer",
+            category=category,
+            dtype_per_channel=dtype_per_channel,
+        )
+        assert layer.dtype_per_channel == np.dtype(dtype_per_channel)
+    else:
+        with pytest.raises(
+            ValueError,
+            match="Supported dtypes are:",
+        ):
+            ds.add_layer(
+                "test_layer",
+                category=category,
+                dtype_per_channel=dtype_per_channel,
+            )
+
+
 def test_pickle_view() -> None:
     ds_path = prepare_dataset_path(DataFormat.WKW, TESTOUTPUT_DIR, "pickle")
     ds = Dataset(ds_path, voxel_size=(1, 1, 1))

webknossos/webknossos/dataset/dataset.py

@@ -1299,6 +1299,39 @@ def add_layer(
         else:
             dtype_per_channel = np.dtype("uint" + str(DEFAULT_BIT_DEPTH))
 
+        # assert that the dtype_per_channel is supported by webknossos
+        if category == COLOR_CATEGORY:
+            color_dtypes = (
+                "uint8",
+                "uint16",
+                "uint32",
+                "int8",
+                "int16",
+                "int32",
+                "float32",
+            )
+            if dtype_per_channel.name not in color_dtypes:
+                raise ValueError(
+                    f"Cannot add color layer with dtype {dtype_per_channel.name}. "
+                    f"Supported dtypes are: {', '.join(color_dtypes)}.",
+                )
+        else:
+            segmentation_dtypes = (
+                "uint8",
+                "uint16",
+                "uint32",
+                "uint64",
+                "int8",
+                "int16",
+                "int32",
+                "int64",
+            )
+            if dtype_per_channel.name not in segmentation_dtypes:
+                raise ValueError(
+                    f"Cannot add segmentation layer with dtype {dtype_per_channel.name}. "
+                    f"Supported dtypes are: {', '.join(segmentation_dtypes)}.",
+                )
+
         if layer_name in self.layers.keys():
             raise IndexError(
                 f"Adding layer {layer_name} failed. There is already a layer with this name"