add support for custom loss

enhancer/models/model.py

@@ -2,7 +2,7 @@ import os
 from collections import defaultdict
 from importlib import import_module
 from pathlib import Path
-from typing import List, Optional, Text, Union
+from typing import Any, List, Optional, Text, Union
 from urllib.parse import urlparse
 
 import numpy as np
@@ -10,6 +10,7 @@ import pytorch_lightning as pl
 import torch
 from huggingface_hub import cached_download, hf_hub_url
 from pytorch_lightning.utilities.cloud_io import load as pl_load
+from torch import nn
 from torch.optim import Adam
 
 from enhancer.data.dataset import EnhancerDataset
@@ -49,7 +50,7 @@ class Model(pl.LightningModule):
         dataset: Optional[EnhancerDataset] = None,
         duration: Optional[float] = None,
         loss: Union[str, List] = "mse",
-        metric: Union[str, List] = "mse",
+        metric: Union[str, List, Any] = "mse",
     ):
         super().__init__()
         assert (
@@ -86,10 +87,11 @@ class Model(pl.LightningModule):
     @metric.setter
     def metric(self, metric):
         self._metric = []
-        if isinstance(metric, str):
+        if isinstance(metric, (str, nn.Module)):
             metric = [metric]
 
         for func in metric:
+            if isinstance(func, str):
                 if func in LOSS_MAP.keys():
                     if func in ("pesq", "stoi"):
                         self._metric.append(
@@ -97,9 +99,13 @@ class Model(pl.LightningModule):
                         )
                     else:
                         self._metric.append(LOSS_MAP[func]())
-
                 else:
-                raise ValueError(f"Invalid metrics {func}")
+                    ValueError(f"Invalid metrics {func}")
+
+            elif isinstance(func, nn.Module):
+                self._metric.append(func)
+            else:
+                raise ValueError("Invalid metrics")
 
     @property
     def dataset(self):