From d96960bb86f1c7e45d5e145a64b07f756f84cb8e Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Wed, 24 Feb 2021 15:13:54 -0500
Subject: [PATCH 01/12] Add ToPIL transformation

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/utility/array.py | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/monai/transforms/utility/array.py b/monai/transforms/utility/array.py
index c0ae40de59..3cc051ca91 100644
--- a/monai/transforms/utility/array.py
+++ b/monai/transforms/utility/array.py
@@ -15,7 +15,7 @@
 
 import logging
 import time
-from typing import Callable, List, Optional, Sequence, Tuple, Union
+from typing import TYPE_CHECKING, Callable, List, Optional, Sequence, Tuple, Union
 
 import numpy as np
 import torch
@@ -25,6 +25,13 @@
 from monai.transforms.utils import extreme_points_to_image, get_extreme_points, map_binary_to_indices
 from monai.utils import ensure_tuple, min_version, optional_import
 
+if TYPE_CHECKING:
+    from PIL import Image as PILImage
+
+    has_pil = True
+else:
+    PILImage, has_pil = optional_import("PIL.Image")
+
 __all__ = [
     "Identity",
     "AsChannelFirst",
@@ -261,6 +268,21 @@ def __call__(self, img: Union[List, Tuple, np.ndarray, torch.Tensor]) -> np.ndar
         return np.ascontiguousarray(img)
 
 
+class ToPIL(Transform):
+    """
+    Converts the input image (in the form of NumPy array or PyTorch Tensor) to PIL image
+    """
+
+    def __call__(self, img: Union[np.ndarray, torch.Tensor]) -> PILImage.Image:
+        """
+        Apply the transform to `img` and make it contiguous.
+        """
+        if isinstance(img, torch.Tensor):
+            img = img.detach().cpu().numpy()
+        img = np.ascontiguousarray(img)
+        return PILImage.fromarray(img)
+
+
 class Transpose(Transform):
     """
     Transposes the input image based on the given `indices` dimension ordering.

From 92a9eb3e398ad898ec0d5db60ec77b939f84a3bb Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Wed, 24 Feb 2021 15:17:13 -0500
Subject: [PATCH 02/12] Add ToPILd, ToPILD, ToPILDict

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/utility/dictionary.py | 40 ++++++++++++++++++++++----
 1 file changed, 35 insertions(+), 5 deletions(-)

diff --git a/monai/transforms/utility/dictionary.py b/monai/transforms/utility/dictionary.py
index f374b82d76..cb6ac6a21e 100644
--- a/monai/transforms/utility/dictionary.py
+++ b/monai/transforms/utility/dictionary.py
@@ -17,7 +17,7 @@
 
 import copy
 import logging
-from typing import Any, Callable, Dict, Hashable, List, Mapping, Optional, Sequence, Tuple, Union
+from typing import TYPE_CHECKING, Any, Callable, Dict, Hashable, List, Mapping, Optional, Sequence, Tuple, Union
 
 import numpy as np
 import torch
@@ -40,12 +40,16 @@
     SplitChannel,
     SqueezeDim,
     ToNumpy,
+    ToPIL,
     TorchVision,
     ToTensor,
 )
 from monai.transforms.utils import extreme_points_to_image, get_extreme_points
 from monai.utils import ensure_tuple, ensure_tuple_rep
 
+if TYPE_CHECKING:
+    from PIL import Image as PILImage
+
 __all__ = [
     "Identityd",
     "AsChannelFirstd",
@@ -56,6 +60,7 @@
     "CastToTyped",
     "ToTensord",
     "ToNumpyd",
+    "ToPILd",
     "DeleteItemsd",
     "SelectItemsd",
     "SqueezeDimd",
@@ -322,8 +327,8 @@ def __init__(self, keys: KeysCollection) -> None:
         self.converter = ToTensor()
 
     def __call__(
-        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor]]
-    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor]]:
+        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]
+    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]:
         d = dict(data)
         for key in self.keys:
             d[key] = self.converter(d[key])
@@ -345,8 +350,31 @@ def __init__(self, keys: KeysCollection) -> None:
         self.converter = ToNumpy()
 
     def __call__(
-        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor]]
-    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor]]:
+        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]
+    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]:
+        d = dict(data)
+        for key in self.keys:
+            d[key] = self.converter(d[key])
+        return d
+
+
+class ToPILd(MapTransform):
+    """
+    Dictionary-based wrapper of :py:class:`monai.transforms.ToNumpy`.
+    """
+
+    def __init__(self, keys: KeysCollection) -> None:
+        """
+        Args:
+            keys: keys of the corresponding items to be transformed.
+                See also: :py:class:`monai.transforms.compose.MapTransform`
+        """
+        super().__init__(keys)
+        self.converter = ToPIL()
+
+    def __call__(
+        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]
+    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]:
         d = dict(data)
         for key in self.keys:
             d[key] = self.converter(d[key])
@@ -840,6 +868,8 @@ def __call__(self, data: Mapping[Hashable, torch.Tensor]) -> Dict[Hashable, torc
 SplitChannelD = SplitChannelDict = SplitChanneld
 CastToTypeD = CastToTypeDict = CastToTyped
 ToTensorD = ToTensorDict = ToTensord
+ToNumpyD = ToNumpyDict = ToNumpyd
+ToPILD = ToPILDict = ToPILd
 DeleteItemsD = DeleteItemsDict = DeleteItemsd
 SqueezeDimD = SqueezeDimDict = SqueezeDimd
 DataStatsD = DataStatsDict = DataStatsd

From d3673296e6cda9f429df14fca91103ee7546a003 Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Wed, 24 Feb 2021 15:18:19 -0500
Subject: [PATCH 03/12] Remove has_pil

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/utility/array.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/monai/transforms/utility/array.py b/monai/transforms/utility/array.py
index 3cc051ca91..fad82cff9d 100644
--- a/monai/transforms/utility/array.py
+++ b/monai/transforms/utility/array.py
@@ -27,10 +27,8 @@
 
 if TYPE_CHECKING:
     from PIL import Image as PILImage
-
-    has_pil = True
 else:
-    PILImage, has_pil = optional_import("PIL.Image")
+    PILImage, _ = optional_import("PIL.Image")
 
 __all__ = [
     "Identity",

From 99f5de4684e13a8a03e8ba8861000d4a25ca1de4 Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Wed, 24 Feb 2021 15:19:48 -0500
Subject: [PATCH 04/12] Include ToPIL, ToPILd, ToPILD, and ToPILDict

Also include ToNumpyD, ToNumpyDict, TorchVisionD, and TorchVisionDict

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/__init__.py | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/monai/transforms/__init__.py b/monai/transforms/__init__.py
index 4dc7744755..cd6a78ad09 100644
--- a/monai/transforms/__init__.py
+++ b/monai/transforms/__init__.py
@@ -253,6 +253,7 @@
     ToNumpy,
     TorchVision,
     ToTensor,
+    ToPIL,
     Transpose,
 )
 from .utility.dictionary import (
@@ -315,7 +316,14 @@
     SqueezeDimD,
     SqueezeDimDict,
     ToNumpyd,
+    ToNumpyD,
+    ToNumpyDict,
+    ToPILd,
+    ToPILD,
+    ToPILDict,
     TorchVisiond,
+    TorchVisionD,
+    TorchVisionDict,
     ToTensord,
     ToTensorD,
     ToTensorDict,

From 0d32f8ff5f5c5cba1a5e03861c101e09edd73570 Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Wed, 24 Feb 2021 15:23:13 -0500
Subject: [PATCH 05/12] Fix a typing issue

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/utility/dictionary.py | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/monai/transforms/utility/dictionary.py b/monai/transforms/utility/dictionary.py
index cb6ac6a21e..ac1871bb72 100644
--- a/monai/transforms/utility/dictionary.py
+++ b/monai/transforms/utility/dictionary.py
@@ -327,8 +327,8 @@ def __init__(self, keys: KeysCollection) -> None:
         self.converter = ToTensor()
 
     def __call__(
-        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]
-    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]:
+        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]
+    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]:
         d = dict(data)
         for key in self.keys:
             d[key] = self.converter(d[key])
@@ -350,8 +350,8 @@ def __init__(self, keys: KeysCollection) -> None:
         self.converter = ToNumpy()
 
     def __call__(
-        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]
-    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]:
+        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]
+    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]:
         d = dict(data)
         for key in self.keys:
             d[key] = self.converter(d[key])
@@ -373,8 +373,8 @@ def __init__(self, keys: KeysCollection) -> None:
         self.converter = ToPIL()
 
     def __call__(
-        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]
-    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage]]:
+        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]
+    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]:
         d = dict(data)
         for key in self.keys:
             d[key] = self.converter(d[key])

From 6a8e0a6112423f980b413f82e24d70df54e67309 Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Thu, 25 Feb 2021 09:27:05 -0500
Subject: [PATCH 06/12] Fix PIL optional import

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/utility/array.py      | 3 ++-
 monai/transforms/utility/dictionary.py | 4 +++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/monai/transforms/utility/array.py b/monai/transforms/utility/array.py
index fad82cff9d..ecc329a7fe 100644
--- a/monai/transforms/utility/array.py
+++ b/monai/transforms/utility/array.py
@@ -275,9 +275,10 @@ def __call__(self, img: Union[np.ndarray, torch.Tensor]) -> PILImage.Image:
         """
         Apply the transform to `img` and make it contiguous.
         """
+        if isinstance(img, PILImage.Image):
+            return img
         if isinstance(img, torch.Tensor):
             img = img.detach().cpu().numpy()
-        img = np.ascontiguousarray(img)
         return PILImage.fromarray(img)
 
 
diff --git a/monai/transforms/utility/dictionary.py b/monai/transforms/utility/dictionary.py
index ac1871bb72..48a5c847c6 100644
--- a/monai/transforms/utility/dictionary.py
+++ b/monai/transforms/utility/dictionary.py
@@ -45,10 +45,12 @@
     ToTensor,
 )
 from monai.transforms.utils import extreme_points_to_image, get_extreme_points
-from monai.utils import ensure_tuple, ensure_tuple_rep
+from monai.utils import ensure_tuple, ensure_tuple_rep, optional_import
 
 if TYPE_CHECKING:
     from PIL import Image as PILImage
+else:
+    PILImage, _ = optional_import("PIL.Image")
 
 __all__ = [
     "Identityd",

From 396547b76b04dce848cd217e5a39257e2b7f28cd Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Thu, 25 Feb 2021 09:27:38 -0500
Subject: [PATCH 07/12] Add unittests for ToPIL and ToPILD

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 tests/test_to_pil.py  | 50 ++++++++++++++++++++++++++++++++++++++++++
 tests/test_to_pild.py | 51 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 101 insertions(+)
 create mode 100644 tests/test_to_pil.py
 create mode 100644 tests/test_to_pild.py

diff --git a/tests/test_to_pil.py b/tests/test_to_pil.py
new file mode 100644
index 0000000000..2ffb29557a
--- /dev/null
+++ b/tests/test_to_pil.py
@@ -0,0 +1,50 @@
+# Copyright 2020 - 2021 MONAI Consortium
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#     http://www.apache.org/licenses/LICENSE-2.0
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import unittest
+
+import numpy as np
+import torch
+import PIL.Image as PILImage
+
+from parameterized import parameterized
+from monai.transforms import ToPIL
+
+TEST_CASE_ARRAY_1 = [np.array([[1.0, 2.0], [3.0, 4.0]])]
+TEST_CASE_TENSOR_1 = [torch.tensor([[1.0, 2.0], [3.0, 4.0]])]
+
+
+class TestToPIL(unittest.TestCase):
+    @parameterized.expand([TEST_CASE_ARRAY_1])
+    def test_numpy_input(self, test_data):
+        self.assertTrue(isinstance(test_data, np.ndarray))
+        result = ToPIL()(test_data)
+        self.assertTrue(isinstance(result, PILImage.Image))
+        np.testing.assert_allclose(np.array(result), test_data)
+
+    @parameterized.expand([TEST_CASE_TENSOR_1])
+    def test_tensor_input(self, test_data):
+        self.assertTrue(isinstance(test_data, torch.Tensor))
+        result = ToPIL()(test_data)
+        self.assertTrue(isinstance(result, PILImage.Image))
+        np.testing.assert_allclose(np.array(result), test_data.numpy())
+
+    @parameterized.expand([TEST_CASE_ARRAY_1])
+    def test_pil_input(self, test_data):
+        test_data_pil = PILImage.fromarray(test_data)
+        self.assertTrue(isinstance(test_data_pil, PILImage.Image))
+        result = ToPIL()(test_data_pil)
+        self.assertTrue(isinstance(result, PILImage.Image))
+        np.testing.assert_allclose(np.array(result), test_data)
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/tests/test_to_pild.py b/tests/test_to_pild.py
new file mode 100644
index 0000000000..6fe47f1a95
--- /dev/null
+++ b/tests/test_to_pild.py
@@ -0,0 +1,51 @@
+# Copyright 2020 - 2021 MONAI Consortium
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#     http://www.apache.org/licenses/LICENSE-2.0
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import unittest
+
+import numpy as np
+import torch
+import PIL.Image as PILImage
+
+from parameterized import parameterized
+from monai.transforms import ToPILD, ToNumpyd
+
+TEST_CASE_ARRAY_1 = [{"keys": "image"}, {"image": np.array([[1.0, 2.0], [3.0, 4.0]])}]
+TEST_CASE__TENSOR_1 = [{"keys": "image"}, {"image": torch.tensor([[1.0, 2.0], [3.0, 4.0]])}]
+
+
+class TestToPIL(unittest.TestCase):
+    @parameterized.expand([TEST_CASE_ARRAY_1])
+    def test_numpy_input(self, input_param, test_data):
+        self.assertTrue(isinstance(test_data[input_param['keys']], np.ndarray))
+        result = ToPILD(**input_param)(test_data)[input_param['keys']]
+        self.assertTrue(isinstance(result, PILImage.Image))
+        np.testing.assert_allclose(np.array(result), test_data[input_param['keys']])
+
+    @parameterized.expand([TEST_CASE__TENSOR_1])
+    def test_tensor_input(self, input_param, test_data):
+        self.assertTrue(isinstance(test_data[input_param['keys']], torch.Tensor))
+        result = ToPILD(**input_param)(test_data)[input_param['keys']]
+        self.assertTrue(isinstance(result, PILImage.Image))
+        np.testing.assert_allclose(np.array(result), test_data[input_param['keys']].numpy())
+
+    @parameterized.expand([TEST_CASE_ARRAY_1])
+    def test_pil_input(self, input_param, test_data):
+        input_array = test_data[input_param['keys']]
+        test_data[input_param['keys']] = PILImage.fromarray(input_array)
+        self.assertTrue(isinstance(test_data[input_param['keys']], PILImage.Image))
+        result = ToPILD(**input_param)(test_data)[input_param['keys']]
+        self.assertTrue(isinstance(result, PILImage.Image))
+        np.testing.assert_allclose(np.array(result), test_data[input_param['keys']])
+
+
+if __name__ == "__main__":
+    unittest.main()

From cfb5519faa5e8ebf461889bb18b51471a940a7ec Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Thu, 25 Feb 2021 10:09:05 -0500
Subject: [PATCH 08/12] Fix formatting

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/__init__.py |  2 +-
 tests/test_to_pild.py        | 24 ++++++++++++------------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/monai/transforms/__init__.py b/monai/transforms/__init__.py
index cd6a78ad09..6b85d5e983 100644
--- a/monai/transforms/__init__.py
+++ b/monai/transforms/__init__.py
@@ -251,9 +251,9 @@
     SplitChannel,
     SqueezeDim,
     ToNumpy,
+    ToPIL,
     TorchVision,
     ToTensor,
-    ToPIL,
     Transpose,
 )
 from .utility.dictionary import (
diff --git a/tests/test_to_pild.py b/tests/test_to_pild.py
index 6fe47f1a95..bb4f2e8a71 100644
--- a/tests/test_to_pild.py
+++ b/tests/test_to_pild.py
@@ -16,7 +16,7 @@
 import PIL.Image as PILImage
 
 from parameterized import parameterized
-from monai.transforms import ToPILD, ToNumpyd
+from monai.transforms import ToPILD
 
 TEST_CASE_ARRAY_1 = [{"keys": "image"}, {"image": np.array([[1.0, 2.0], [3.0, 4.0]])}]
 TEST_CASE__TENSOR_1 = [{"keys": "image"}, {"image": torch.tensor([[1.0, 2.0], [3.0, 4.0]])}]
@@ -25,26 +25,26 @@
 class TestToPIL(unittest.TestCase):
     @parameterized.expand([TEST_CASE_ARRAY_1])
     def test_numpy_input(self, input_param, test_data):
-        self.assertTrue(isinstance(test_data[input_param['keys']], np.ndarray))
-        result = ToPILD(**input_param)(test_data)[input_param['keys']]
+        self.assertTrue(isinstance(test_data[input_param["keys"]], np.ndarray))
+        result = ToPILD(**input_param)(test_data)[input_param["keys"]]
         self.assertTrue(isinstance(result, PILImage.Image))
-        np.testing.assert_allclose(np.array(result), test_data[input_param['keys']])
+        np.testing.assert_allclose(np.array(result), test_data[input_param["keys"]])
 
     @parameterized.expand([TEST_CASE__TENSOR_1])
     def test_tensor_input(self, input_param, test_data):
-        self.assertTrue(isinstance(test_data[input_param['keys']], torch.Tensor))
-        result = ToPILD(**input_param)(test_data)[input_param['keys']]
+        self.assertTrue(isinstance(test_data[input_param["keys"]], torch.Tensor))
+        result = ToPILD(**input_param)(test_data)[input_param["keys"]]
         self.assertTrue(isinstance(result, PILImage.Image))
-        np.testing.assert_allclose(np.array(result), test_data[input_param['keys']].numpy())
+        np.testing.assert_allclose(np.array(result), test_data[input_param["keys"]].numpy())
 
     @parameterized.expand([TEST_CASE_ARRAY_1])
     def test_pil_input(self, input_param, test_data):
-        input_array = test_data[input_param['keys']]
-        test_data[input_param['keys']] = PILImage.fromarray(input_array)
-        self.assertTrue(isinstance(test_data[input_param['keys']], PILImage.Image))
-        result = ToPILD(**input_param)(test_data)[input_param['keys']]
+        input_array = test_data[input_param["keys"]]
+        test_data[input_param["keys"]] = PILImage.fromarray(input_array)
+        self.assertTrue(isinstance(test_data[input_param["keys"]], PILImage.Image))
+        result = ToPILD(**input_param)(test_data)[input_param["keys"]]
         self.assertTrue(isinstance(result, PILImage.Image))
-        np.testing.assert_allclose(np.array(result), test_data[input_param['keys']])
+        np.testing.assert_allclose(np.array(result), test_data[input_param["keys"]])
 
 
 if __name__ == "__main__":

From 96bcfdc10f9b9365133e69b8d1fc9342c4b5c1bb Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Thu, 25 Feb 2021 10:34:03 -0500
Subject: [PATCH 09/12] Fix formatting

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 tests/test_to_pil.py  | 4 ++--
 tests/test_to_pild.py | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/tests/test_to_pil.py b/tests/test_to_pil.py
index 2ffb29557a..9c6e6a2dcb 100644
--- a/tests/test_to_pil.py
+++ b/tests/test_to_pil.py
@@ -12,10 +12,10 @@
 import unittest
 
 import numpy as np
-import torch
 import PIL.Image as PILImage
-
+import torch
 from parameterized import parameterized
+
 from monai.transforms import ToPIL
 
 TEST_CASE_ARRAY_1 = [np.array([[1.0, 2.0], [3.0, 4.0]])]
diff --git a/tests/test_to_pild.py b/tests/test_to_pild.py
index bb4f2e8a71..49a62c48d8 100644
--- a/tests/test_to_pild.py
+++ b/tests/test_to_pild.py
@@ -12,10 +12,10 @@
 import unittest
 
 import numpy as np
-import torch
 import PIL.Image as PILImage
-
+import torch
 from parameterized import parameterized
+
 from monai.transforms import ToPILD
 
 TEST_CASE_ARRAY_1 = [{"keys": "image"}, {"image": np.array([[1.0, 2.0], [3.0, 4.0]])}]

From 85704538d971daddc40a4eda86c7a6278c30196a Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Thu, 25 Feb 2021 10:37:17 -0500
Subject: [PATCH 10/12] Add PILImage.Image as the input for ToNumpy and
 ToTensor

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/utility/array.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/monai/transforms/utility/array.py b/monai/transforms/utility/array.py
index ecc329a7fe..4795d24c6c 100644
--- a/monai/transforms/utility/array.py
+++ b/monai/transforms/utility/array.py
@@ -243,7 +243,7 @@ class ToTensor(Transform):
     Converts the input image to a tensor without applying any other transformations.
     """
 
-    def __call__(self, img: Union[np.ndarray, torch.Tensor]) -> torch.Tensor:
+    def __call__(self, img: Union[np.ndarray, torch.Tensor, PILImage.Image]) -> torch.Tensor:
         """
         Apply the transform to `img` and make it contiguous.
         """
@@ -257,7 +257,7 @@ class ToNumpy(Transform):
     Converts the input data to numpy array, can support list or tuple of numbers and PyTorch Tensor.
     """
 
-    def __call__(self, img: Union[List, Tuple, np.ndarray, torch.Tensor]) -> np.ndarray:
+    def __call__(self, img: Union[List, Tuple, np.ndarray, torch.Tensor, PILImage.Image]) -> np.ndarray:
         """
         Apply the transform to `img` and make it contiguous.
         """
@@ -271,7 +271,7 @@ class ToPIL(Transform):
     Converts the input image (in the form of NumPy array or PyTorch Tensor) to PIL image
     """
 
-    def __call__(self, img: Union[np.ndarray, torch.Tensor]) -> PILImage.Image:
+    def __call__(self, img: Union[np.ndarray, torch.Tensor, PILImage.Image]) -> PILImage.Image:
         """
         Apply the transform to `img` and make it contiguous.
         """

From 302284a7525315bae827837ce5ea07307048821b Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Thu, 25 Feb 2021 17:03:30 -0500
Subject: [PATCH 11/12] Fix type checking issue for PIL.Image.Image

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/utility/array.py      | 18 ++++++++------
 monai/transforms/utility/dictionary.py | 18 ++++++++------
 tests/test_to_pil.py                   | 26 +++++++++++++++-----
 tests/test_to_pild.py                  | 34 ++++++++++++++++++--------
 4 files changed, 65 insertions(+), 31 deletions(-)

diff --git a/monai/transforms/utility/array.py b/monai/transforms/utility/array.py
index 4795d24c6c..74f2f82ad5 100644
--- a/monai/transforms/utility/array.py
+++ b/monai/transforms/utility/array.py
@@ -26,9 +26,13 @@
 from monai.utils import ensure_tuple, min_version, optional_import
 
 if TYPE_CHECKING:
-    from PIL import Image as PILImage
+    from PIL.Image import Image as PILImageImage
+    from PIL.Image import fromarray as PILImage_fromarray
+
+    has_pil = True
 else:
-    PILImage, _ = optional_import("PIL.Image")
+    PILImage_fromarray, has_pil = optional_import("PIL.Image", name="fromarray")
+    PILImageImage, _ = optional_import("PIL.Image", name="Image")
 
 __all__ = [
     "Identity",
@@ -243,7 +247,7 @@ class ToTensor(Transform):
     Converts the input image to a tensor without applying any other transformations.
     """
 
-    def __call__(self, img: Union[np.ndarray, torch.Tensor, PILImage.Image]) -> torch.Tensor:
+    def __call__(self, img: Union[np.ndarray, torch.Tensor, PILImageImage]) -> torch.Tensor:
         """
         Apply the transform to `img` and make it contiguous.
         """
@@ -257,7 +261,7 @@ class ToNumpy(Transform):
     Converts the input data to numpy array, can support list or tuple of numbers and PyTorch Tensor.
     """
 
-    def __call__(self, img: Union[List, Tuple, np.ndarray, torch.Tensor, PILImage.Image]) -> np.ndarray:
+    def __call__(self, img: Union[List, Tuple, np.ndarray, torch.Tensor, PILImageImage]) -> np.ndarray:
         """
         Apply the transform to `img` and make it contiguous.
         """
@@ -271,15 +275,15 @@ class ToPIL(Transform):
     Converts the input image (in the form of NumPy array or PyTorch Tensor) to PIL image
     """
 
-    def __call__(self, img: Union[np.ndarray, torch.Tensor, PILImage.Image]) -> PILImage.Image:
+    def __call__(self, img: Union[np.ndarray, torch.Tensor, PILImageImage]) -> PILImageImage:
         """
         Apply the transform to `img` and make it contiguous.
         """
-        if isinstance(img, PILImage.Image):
+        if isinstance(img, PILImageImage):
             return img
         if isinstance(img, torch.Tensor):
             img = img.detach().cpu().numpy()
-        return PILImage.fromarray(img)
+        return PILImage_fromarray(img)
 
 
 class Transpose(Transform):
diff --git a/monai/transforms/utility/dictionary.py b/monai/transforms/utility/dictionary.py
index 48a5c847c6..ed1c61f665 100644
--- a/monai/transforms/utility/dictionary.py
+++ b/monai/transforms/utility/dictionary.py
@@ -48,9 +48,11 @@
 from monai.utils import ensure_tuple, ensure_tuple_rep, optional_import
 
 if TYPE_CHECKING:
-    from PIL import Image as PILImage
+    from PIL.Image import Image as PILImageImage
+
+    has_pil = True
 else:
-    PILImage, _ = optional_import("PIL.Image")
+    PILImageImage, has_pil = optional_import("PIL.Image", name="Image")
 
 __all__ = [
     "Identityd",
@@ -329,8 +331,8 @@ def __init__(self, keys: KeysCollection) -> None:
         self.converter = ToTensor()
 
     def __call__(
-        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]
-    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]:
+        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImageImage]]
+    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImageImage]]:
         d = dict(data)
         for key in self.keys:
             d[key] = self.converter(d[key])
@@ -352,8 +354,8 @@ def __init__(self, keys: KeysCollection) -> None:
         self.converter = ToNumpy()
 
     def __call__(
-        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]
-    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]:
+        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImageImage]]
+    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImageImage]]:
         d = dict(data)
         for key in self.keys:
             d[key] = self.converter(d[key])
@@ -375,8 +377,8 @@ def __init__(self, keys: KeysCollection) -> None:
         self.converter = ToPIL()
 
     def __call__(
-        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]
-    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImage.Image]]:
+        self, data: Mapping[Hashable, Union[np.ndarray, torch.Tensor, PILImageImage]]
+    ) -> Dict[Hashable, Union[np.ndarray, torch.Tensor, PILImageImage]]:
         d = dict(data)
         for key in self.keys:
             d[key] = self.converter(d[key])
diff --git a/tests/test_to_pil.py b/tests/test_to_pil.py
index 9c6e6a2dcb..7ceb2170d7 100644
--- a/tests/test_to_pil.py
+++ b/tests/test_to_pil.py
@@ -10,13 +10,24 @@
 # limitations under the License.
 
 import unittest
+from typing import TYPE_CHECKING
+from unittest import skipUnless
 
 import numpy as np
-import PIL.Image as PILImage
 import torch
 from parameterized import parameterized
 
 from monai.transforms import ToPIL
+from monai.utils import optional_import
+
+if TYPE_CHECKING:
+    from PIL.Image import Image as PILImageImage
+    from PIL.Image import fromarray as PILImage_fromarray
+
+    has_pil = True
+else:
+    PILImage_fromarray, has_pil = optional_import("PIL.Image", name="fromarray")
+    PILImageImage, _ = optional_import("PIL.Image", name="Image")
 
 TEST_CASE_ARRAY_1 = [np.array([[1.0, 2.0], [3.0, 4.0]])]
 TEST_CASE_TENSOR_1 = [torch.tensor([[1.0, 2.0], [3.0, 4.0]])]
@@ -24,25 +35,28 @@
 
 class TestToPIL(unittest.TestCase):
     @parameterized.expand([TEST_CASE_ARRAY_1])
+    @skipUnless(has_pil, "Requires `pillow` package.")
     def test_numpy_input(self, test_data):
         self.assertTrue(isinstance(test_data, np.ndarray))
         result = ToPIL()(test_data)
-        self.assertTrue(isinstance(result, PILImage.Image))
+        self.assertTrue(isinstance(result, PILImageImage))
         np.testing.assert_allclose(np.array(result), test_data)
 
     @parameterized.expand([TEST_CASE_TENSOR_1])
+    @skipUnless(has_pil, "Requires `pillow` package.")
     def test_tensor_input(self, test_data):
         self.assertTrue(isinstance(test_data, torch.Tensor))
         result = ToPIL()(test_data)
-        self.assertTrue(isinstance(result, PILImage.Image))
+        self.assertTrue(isinstance(result, PILImageImage))
         np.testing.assert_allclose(np.array(result), test_data.numpy())
 
     @parameterized.expand([TEST_CASE_ARRAY_1])
+    @skipUnless(has_pil, "Requires `pillow` package.")
     def test_pil_input(self, test_data):
-        test_data_pil = PILImage.fromarray(test_data)
-        self.assertTrue(isinstance(test_data_pil, PILImage.Image))
+        test_data_pil = PILImage_fromarray(test_data)
+        self.assertTrue(isinstance(test_data_pil, PILImageImage))
         result = ToPIL()(test_data_pil)
-        self.assertTrue(isinstance(result, PILImage.Image))
+        self.assertTrue(isinstance(result, PILImageImage))
         np.testing.assert_allclose(np.array(result), test_data)
 
 
diff --git a/tests/test_to_pild.py b/tests/test_to_pild.py
index 49a62c48d8..7ddac93b47 100644
--- a/tests/test_to_pild.py
+++ b/tests/test_to_pild.py
@@ -10,13 +10,24 @@
 # limitations under the License.
 
 import unittest
+from typing import TYPE_CHECKING
+from unittest import skipUnless
 
 import numpy as np
-import PIL.Image as PILImage
 import torch
 from parameterized import parameterized
 
-from monai.transforms import ToPILD
+from monai.transforms import ToPILd
+from monai.utils import optional_import
+
+if TYPE_CHECKING:
+    from PIL.Image import Image as PILImageImage
+    from PIL.Image import fromarray as PILImage_fromarray
+
+    has_pil = True
+else:
+    PILImage_fromarray, has_pil = optional_import("PIL.Image", name="fromarray")
+    PILImageImage, _ = optional_import("PIL.Image", name="Image")
 
 TEST_CASE_ARRAY_1 = [{"keys": "image"}, {"image": np.array([[1.0, 2.0], [3.0, 4.0]])}]
 TEST_CASE__TENSOR_1 = [{"keys": "image"}, {"image": torch.tensor([[1.0, 2.0], [3.0, 4.0]])}]
@@ -24,26 +35,29 @@
 
 class TestToPIL(unittest.TestCase):
     @parameterized.expand([TEST_CASE_ARRAY_1])
+    @skipUnless(has_pil, "Requires `pillow` package.")
     def test_numpy_input(self, input_param, test_data):
         self.assertTrue(isinstance(test_data[input_param["keys"]], np.ndarray))
-        result = ToPILD(**input_param)(test_data)[input_param["keys"]]
-        self.assertTrue(isinstance(result, PILImage.Image))
+        result = ToPILd(**input_param)(test_data)[input_param["keys"]]
+        self.assertTrue(isinstance(result, PILImageImage))
         np.testing.assert_allclose(np.array(result), test_data[input_param["keys"]])
 
     @parameterized.expand([TEST_CASE__TENSOR_1])
+    @skipUnless(has_pil, "Requires `pillow` package.")
     def test_tensor_input(self, input_param, test_data):
         self.assertTrue(isinstance(test_data[input_param["keys"]], torch.Tensor))
-        result = ToPILD(**input_param)(test_data)[input_param["keys"]]
-        self.assertTrue(isinstance(result, PILImage.Image))
+        result = ToPILd(**input_param)(test_data)[input_param["keys"]]
+        self.assertTrue(isinstance(result, PILImageImage))
         np.testing.assert_allclose(np.array(result), test_data[input_param["keys"]].numpy())
 
     @parameterized.expand([TEST_CASE_ARRAY_1])
+    @skipUnless(has_pil, "Requires `pillow` package.")
     def test_pil_input(self, input_param, test_data):
         input_array = test_data[input_param["keys"]]
-        test_data[input_param["keys"]] = PILImage.fromarray(input_array)
-        self.assertTrue(isinstance(test_data[input_param["keys"]], PILImage.Image))
-        result = ToPILD(**input_param)(test_data)[input_param["keys"]]
-        self.assertTrue(isinstance(result, PILImage.Image))
+        test_data[input_param["keys"]] = PILImage_fromarray(input_array)
+        self.assertTrue(isinstance(test_data[input_param["keys"]], PILImageImage))
+        result = ToPILd(**input_param)(test_data)[input_param["keys"]]
+        self.assertTrue(isinstance(result, PILImageImage))
         np.testing.assert_allclose(np.array(result), test_data[input_param["keys"]])
 
 

From 32c9f1a1895eb9298cdd4343523e2b5578495d0f Mon Sep 17 00:00:00 2001
From: Behrooz <3968947+behxyz@users.noreply.github.com>
Date: Thu, 25 Feb 2021 17:12:03 -0500
Subject: [PATCH 12/12] Change PILImage_fromarray to lower case

Signed-off-by: Behrooz <3968947+behxyz@users.noreply.github.com>
---
 monai/transforms/utility/array.py | 8 ++++----
 tests/test_to_pil.py              | 6 +++---
 tests/test_to_pild.py             | 6 +++---
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/monai/transforms/utility/array.py b/monai/transforms/utility/array.py
index 74f2f82ad5..077a126162 100644
--- a/monai/transforms/utility/array.py
+++ b/monai/transforms/utility/array.py
@@ -27,12 +27,12 @@
 
 if TYPE_CHECKING:
     from PIL.Image import Image as PILImageImage
-    from PIL.Image import fromarray as PILImage_fromarray
+    from PIL.Image import fromarray as pil_image_fromarray
 
     has_pil = True
 else:
-    PILImage_fromarray, has_pil = optional_import("PIL.Image", name="fromarray")
-    PILImageImage, _ = optional_import("PIL.Image", name="Image")
+    PILImageImage, has_pil = optional_import("PIL.Image", name="Image")
+    pil_image_fromarray, _ = optional_import("PIL.Image", name="fromarray")
 
 __all__ = [
     "Identity",
@@ -283,7 +283,7 @@ def __call__(self, img: Union[np.ndarray, torch.Tensor, PILImageImage]) -> PILIm
             return img
         if isinstance(img, torch.Tensor):
             img = img.detach().cpu().numpy()
-        return PILImage_fromarray(img)
+        return pil_image_fromarray(img)
 
 
 class Transpose(Transform):
diff --git a/tests/test_to_pil.py b/tests/test_to_pil.py
index 7ceb2170d7..ec63750ce4 100644
--- a/tests/test_to_pil.py
+++ b/tests/test_to_pil.py
@@ -22,11 +22,11 @@
 
 if TYPE_CHECKING:
     from PIL.Image import Image as PILImageImage
-    from PIL.Image import fromarray as PILImage_fromarray
+    from PIL.Image import fromarray as pil_image_fromarray
 
     has_pil = True
 else:
-    PILImage_fromarray, has_pil = optional_import("PIL.Image", name="fromarray")
+    pil_image_fromarray, has_pil = optional_import("PIL.Image", name="fromarray")
     PILImageImage, _ = optional_import("PIL.Image", name="Image")
 
 TEST_CASE_ARRAY_1 = [np.array([[1.0, 2.0], [3.0, 4.0]])]
@@ -53,7 +53,7 @@ def test_tensor_input(self, test_data):
     @parameterized.expand([TEST_CASE_ARRAY_1])
     @skipUnless(has_pil, "Requires `pillow` package.")
     def test_pil_input(self, test_data):
-        test_data_pil = PILImage_fromarray(test_data)
+        test_data_pil = pil_image_fromarray(test_data)
         self.assertTrue(isinstance(test_data_pil, PILImageImage))
         result = ToPIL()(test_data_pil)
         self.assertTrue(isinstance(result, PILImageImage))
diff --git a/tests/test_to_pild.py b/tests/test_to_pild.py
index 7ddac93b47..43778022ee 100644
--- a/tests/test_to_pild.py
+++ b/tests/test_to_pild.py
@@ -22,11 +22,11 @@
 
 if TYPE_CHECKING:
     from PIL.Image import Image as PILImageImage
-    from PIL.Image import fromarray as PILImage_fromarray
+    from PIL.Image import fromarray as pil_image_fromarray
 
     has_pil = True
 else:
-    PILImage_fromarray, has_pil = optional_import("PIL.Image", name="fromarray")
+    pil_image_fromarray, has_pil = optional_import("PIL.Image", name="fromarray")
     PILImageImage, _ = optional_import("PIL.Image", name="Image")
 
 TEST_CASE_ARRAY_1 = [{"keys": "image"}, {"image": np.array([[1.0, 2.0], [3.0, 4.0]])}]
@@ -54,7 +54,7 @@ def test_tensor_input(self, input_param, test_data):
     @skipUnless(has_pil, "Requires `pillow` package.")
     def test_pil_input(self, input_param, test_data):
         input_array = test_data[input_param["keys"]]
-        test_data[input_param["keys"]] = PILImage_fromarray(input_array)
+        test_data[input_param["keys"]] = pil_image_fromarray(input_array)
         self.assertTrue(isinstance(test_data[input_param["keys"]], PILImageImage))
         result = ToPILd(**input_param)(test_data)[input_param["keys"]]
         self.assertTrue(isinstance(result, PILImageImage))