init

finetune/mmseg/models/backbones/timm_backbone.py

@@ -0,0 +1,63 @@
+# Copyright (c) OpenMMLab. All rights reserved.
+try:
+    import timm
+except ImportError:
+    timm = None
+
+from mmengine.model import BaseModule
+from mmengine.registry import MODELS as MMENGINE_MODELS
+
+from mmseg.registry import MODELS
+
+
+@MODELS.register_module()
+class TIMMBackbone(BaseModule):
+    """Wrapper to use backbones from timm library. More details can be found in
+    `timm <https://github.com/rwightman/pytorch-image-models>`_ .
+
+    Args:
+        model_name (str): Name of timm model to instantiate.
+        pretrained (bool): Load pretrained weights if True.
+        checkpoint_path (str): Path of checkpoint to load after
+            model is initialized.
+        in_channels (int): Number of input image channels. Default: 3.
+        init_cfg (dict, optional): Initialization config dict
+        **kwargs: Other timm & model specific arguments.
+    """
+
+    def __init__(
+        self,
+        model_name,
+        features_only=True,
+        pretrained=True,
+        checkpoint_path='',
+        in_channels=3,
+        init_cfg=None,
+        **kwargs,
+    ):
+        if timm is None:
+            raise RuntimeError('timm is not installed')
+        super().__init__(init_cfg)
+        if 'norm_layer' in kwargs:
+            kwargs['norm_layer'] = MMENGINE_MODELS.get(kwargs['norm_layer'])
+        self.timm_model = timm.create_model(
+            model_name=model_name,
+            features_only=features_only,
+            pretrained=pretrained,
+            in_chans=in_channels,
+            checkpoint_path=checkpoint_path,
+            **kwargs,
+        )
+
+        # Make unused parameters None
+        self.timm_model.global_pool = None
+        self.timm_model.fc = None
+        self.timm_model.classifier = None
+
+        # Hack to use pretrained weights from timm
+        if pretrained or checkpoint_path:
+            self._is_init = True
+
+    def forward(self, x):
+        features = self.timm_model(x)
+        return features