Adds external dependency to relevant files, excludes from min tests a…

…nd uses optional_import to import it

docs/source/installation.md

@@ -254,10 +254,10 @@ Since MONAI v0.2.0, the extras syntax such as `pip install 'monai[nibabel]'` is
 - The options are
 
 ```
-[nibabel, skimage, pillow, tensorboard, gdown, ignite, torchvision, itk, tqdm, lmdb, psutil, cucim, openslide, pandas, einops, transformers, mlflow, clearml, matplotlib, tensorboardX, tifffile, imagecodecs, pyyaml, fire, jsonschema, ninja, pynrrd, pydicom, h5py, nni, optuna, onnx, onnxruntime, zarr]
+[nibabel, skimage, pillow, tensorboard, gdown, ignite, torchvision, itk, tqdm, lmdb, psutil, cucim, openslide, pandas, einops, transformers, mlflow, clearml, matplotlib, tensorboardX, tifffile, imagecodecs, pyyaml, fire, jsonschema, ninja, pynrrd, pydicom, h5py, nni, optuna, onnx, onnxruntime, zarr, lpips]
 ```
 
 which correspond to `nibabel`, `scikit-image`, `pillow`, `tensorboard`,
-`gdown`, `pytorch-ignite`, `torchvision`, `itk`, `tqdm`, `lmdb`, `psutil`, `cucim`, `openslide-python`, `pandas`, `einops`, `transformers`, `mlflow`, `clearml`, `matplotlib`, `tensorboardX`, `tifffile`, `imagecodecs`, `pyyaml`, `fire`, `jsonschema`, `ninja`, `pynrrd`, `pydicom`, `h5py`, `nni`, `optuna`, `onnx`, `onnxruntime`, and `zarr` respectively.
+`gdown`, `pytorch-ignite`, `torchvision`, `itk`, `tqdm`, `lmdb`, `psutil`, `cucim`, `openslide-python`, `pandas`, `einops`, `transformers`, `mlflow`, `clearml`, `matplotlib`, `tensorboardX`, `tifffile`, `imagecodecs`, `pyyaml`, `fire`, `jsonschema`, `ninja`, `pynrrd`, `pydicom`, `h5py`, `nni`, `optuna`, `onnx`, `onnxruntime`, `zarr` and `lpips` respectively.
 
 - `pip install 'monai[all]'` installs all the optional dependencies.

monai/losses/perceptual.py

@@ -13,7 +13,10 @@
 
 import torch
 import torch.nn as nn
-from lpips import LPIPS
+
+from monai.utils import optional_import
+
+LPIPS, _ = optional_import("lpips", name="LPIPS")
 from torchvision.models import ResNet50_Weights, resnet50
 from torchvision.models.feature_extraction import create_feature_extractor
 

setup.cfg

@@ -80,6 +80,7 @@ all =
     onnx>=1.13.0
     onnxruntime; python_version <= '3.10'
     zarr
+    lpips==0.1.4
 nibabel =
     nibabel
 ninja =
@@ -145,6 +146,8 @@ onnx =
     onnxruntime; python_version <= '3.10'
 zarr =
     zarr
+lpips =
+    lpips==0.1.4
 # # workaround https://github.com/Project-MONAI/MONAI/issues/5882
 # MetricsReloaded =
 #     MetricsReloaded @ git+https://github.com/Project-MONAI/MetricsReloaded@monai-support#egg=MetricsReloaded

tests/min_tests.py

@@ -204,6 +204,7 @@ def run_testsuit():
         "test_spatial_combine_transforms",
         "test_bundle_workflow",
         "test_zarr_avg_merger",
+        "test_perceptual_loss",
     ]
     assert sorted(exclude_cases) == sorted(set(exclude_cases)), f"Duplicated items in {exclude_cases}"