Added util to save images

src/ptbench/utils/image.py

+# SPDX-FileCopyrightText: Copyright © 2023 Idiap Research Institute <contact@idiap.ch>
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+import os
+
+from typing import Union
+
+import torch
+
+from PIL.Image import Image
+from torchvision import transforms
+
+
+def save_image(img: Union[torch.Tensor, Image], filepath: str) -> None:
+    """Saves a PIL image or a tensor as an image at the specified destination.
+
+    Parameters
+    ----------
+
+    img:
+        A torch.Tensor or PIL.Image to save
+
+    filepath:
+        The file in which to save the image. The format is inferred from the file extension, or defaults to png if not specified.
+    """
+
+    if isinstance(img, torch.Tensor):
+        img = transforms.ToPILImage()(img)
+
+    root, ext = os.path.splitext(filepath)
+
+    if len(ext) == 0:
+        filepath = filepath + ".png"
+
+    img.save(filepath)