Add TimmBackbone model (#22619)

* Add test_backbone for convnext

* Add TimmBackbone model

* Add check for backbone type

* Tidying up - config checks

* Update convnextv2

* Tidy up

* Fix indices & clearer comment

* Exceptions for config checks

* Correclty update config for tests

* Safer imports

* Safer safer imports

* Fix where decorators go

* Update import logic and backbone tests

* More import fixes

* Fixup

* Only import all_models if torch available

* Fix kwarg updates in from_pretrained & main rebase

* Tidy up

* Add tests for AutoBackbone

* Tidy up

* Fix import error

* Fix up

* Install nattan in doc_test_job

* Revert back to setting self._out_xxx directly

* Bug fix - out_indices mapping from out_features

* Fix tests

* Dont accept output_loading_info for Timm models

* Set out_xxx and don't remap

* Use smaller checkpoint for test

* Don't remap timm indices - check out_indices based on stage names

* Skip test as it's n/a

* Apply suggestions from code review

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* Cleaner imports / spelling is hard

---------

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

.circleci/create_circleci_config.py

@@ -128,7 +128,7 @@ class CircleCIJob:
         if self.command_timeout:
             test_command = f"timeout {self.command_timeout} "
         test_command += f"python -m pytest -n {self.pytest_num_workers} " + " ".join(pytest_flags)
-        
+
         if self.parallelism == 1:
             if self.tests_to_run is None:
                 test_command += " << pipeline.parameters.tests_to_run >>"
@@ -456,6 +456,7 @@ doc_test_job = CircleCIJob(
         "pip install -e .[dev]",
         "pip install git+https://github.com/huggingface/accelerate",
         "pip install --upgrade pytest pytest-sugar",
+        "pip install natten",
         "find -name __pycache__ -delete",
         "find . -name \*.pyc -delete",
         # Add an empty file to keep the test step running correctly even no file is selected to be tested.

docs/source/en/index.mdx

@@ -424,6 +424,7 @@ Flax), PyTorch, and/or TensorFlow.
 |             TAPAS             |       ✅       |       ❌       |       ✅        |         ✅         |      ❌      |
 |    Time Series Transformer    |       ❌       |       ❌       |       ✅        |         ❌         |      ❌      |
 |          TimeSformer          |       ❌       |       ❌       |       ✅        |         ❌         |      ❌      |
+|         TimmBackbone          |       ❌       |       ❌       |       ❌        |         ❌         |      ❌      |
 |    Trajectory Transformer     |       ❌       |       ❌       |       ✅        |         ❌         |      ❌      |
 |        Transformer-XL         |       ✅       |       ❌       |       ✅        |         ✅         |      ❌      |
 |             TrOCR             |       ❌       |       ❌       |       ✅        |         ❌         |      ❌      |

src/transformers/__init__.py

@@ -483,6 +483,7 @@ _import_structure = {
         "TimeSeriesTransformerConfig",
     ],
     "models.timesformer": ["TIMESFORMER_PRETRAINED_CONFIG_ARCHIVE_MAP", "TimesformerConfig"],
+    "models.timm_backbone": ["TimmBackboneConfig"],
     "models.trajectory_transformer": [
         "TRAJECTORY_TRANSFORMER_PRETRAINED_CONFIG_ARCHIVE_MAP",
         "TrajectoryTransformerConfig",
@@ -2578,6 +2579,7 @@ else:
             "TimesformerPreTrainedModel",
         ]
     )
+    _import_structure["models.timm_backbone"].extend(["TimmBackbone"])
     _import_structure["models.trajectory_transformer"].extend(
         [
             "TRAJECTORY_TRANSFORMER_PRETRAINED_MODEL_ARCHIVE_LIST",
@@ -4288,6 +4290,7 @@ if TYPE_CHECKING:
         TimeSeriesTransformerConfig,
     )
     from .models.timesformer import TIMESFORMER_PRETRAINED_CONFIG_ARCHIVE_MAP, TimesformerConfig
+    from .models.timm_backbone import TimmBackboneConfig
     from .models.trajectory_transformer import (
         TRAJECTORY_TRANSFORMER_PRETRAINED_CONFIG_ARCHIVE_MAP,
         TrajectoryTransformerConfig,
@@ -6024,6 +6027,7 @@ if TYPE_CHECKING:
             TimesformerModel,
             TimesformerPreTrainedModel,
         )
+        from .models.timm_backbone import TimmBackbone
         from .models.trajectory_transformer import (
             TRAJECTORY_TRANSFORMER_PRETRAINED_MODEL_ARCHIVE_LIST,
             TrajectoryTransformerModel,

src/transformers/models/__init__.py

@@ -186,6 +186,7 @@ from . import (
     tapex,
     time_series_transformer,
     timesformer,
+    timm_backbone,
     trajectory_transformer,
     transfo_xl,
     trocr,

src/transformers/models/auto/auto_factory.py

@@ -19,7 +19,7 @@ from collections import OrderedDict
 
 from ...configuration_utils import PretrainedConfig
 from ...dynamic_module_utils import get_class_from_dynamic_module
-from ...utils import copy_func, logging
+from ...utils import copy_func, logging, requires_backends
 from .configuration_auto import AutoConfig, model_type_to_module_name, replace_list_option_in_docstrings
 
 
@@ -515,6 +515,48 @@ class _BaseAutoModelClass:
         cls._model_mapping.register(config_class, model_class)
 
 
+class _BaseAutoBackboneClass(_BaseAutoModelClass):
+    # Base class for auto backbone models.
+    _model_mapping = None
+
+    @classmethod
+    def _load_timm_backbone_from_pretrained(cls, pretrained_model_name_or_path, *model_args, **kwargs):
+        requires_backends(cls, ["vision", "timm"])
+        from ...models.timm_backbone import TimmBackboneConfig
+
+        config = kwargs.pop("config", TimmBackboneConfig())
+
+        use_timm = kwargs.pop("use_timm_backbone", True)
+        if not use_timm:
+            raise ValueError("`use_timm_backbone` must be `True` for timm backbones")
+
+        if kwargs.get("out_features", None) is not None:
+            raise ValueError("Cannot specify `out_features` for timm backbones")
+
+        if kwargs.get("output_loading_info", False):
+            raise ValueError("Cannot specify `output_loading_info=True` when loading from timm")
+
+        num_channels = kwargs.pop("num_channels", config.num_channels)
+        features_only = kwargs.pop("features_only", config.features_only)
+        use_pretrained_backbone = kwargs.pop("use_pretrained_backbone", config.use_pretrained_backbone)
+        out_indices = kwargs.pop("out_indices", config.out_indices)
+        config = TimmBackboneConfig(
+            backbone=pretrained_model_name_or_path,
+            num_channels=num_channels,
+            features_only=features_only,
+            use_pretrained_backbone=use_pretrained_backbone,
+            out_indices=out_indices,
+        )
+        return super().from_config(config, **kwargs)
+
+    @classmethod
+    def from_pretrained(cls, pretrained_model_name_or_path, *model_args, **kwargs):
+        if kwargs.get("use_timm_backbone", False):
+            return cls._load_timm_backbone_from_pretrained(pretrained_model_name_or_path, *model_args, **kwargs)
+
+        return super().from_pretrained(pretrained_model_name_or_path, *model_args, **kwargs)
+
+
 def insert_head_doc(docstring, head_doc=""):
     if len(head_doc) > 0:
         return docstring.replace(

src/transformers/models/auto/configuration_auto.py

@@ -186,6 +186,7 @@ CONFIG_MAPPING_NAMES = OrderedDict(
         ("tapas", "TapasConfig"),
         ("time_series_transformer", "TimeSeriesTransformerConfig"),
         ("timesformer", "TimesformerConfig"),
+        ("timm_backbone", "TimmBackboneConfig"),
         ("trajectory_transformer", "TrajectoryTransformerConfig"),
         ("transfo-xl", "TransfoXLConfig"),
         ("trocr", "TrOCRConfig"),
@@ -579,6 +580,7 @@ MODEL_NAMES_MAPPING = OrderedDict(
         ("tapex", "TAPEX"),
         ("time_series_transformer", "Time Series Transformer"),
         ("timesformer", "TimeSformer"),
+        ("timm_backbone", "TimmBackbone"),
         ("trajectory_transformer", "Trajectory Transformer"),
         ("transfo-xl", "Transformer-XL"),
         ("trocr", "TrOCR"),

src/transformers/models/auto/modeling_auto.py

@@ -18,7 +18,7 @@ import warnings
 from collections import OrderedDict
 
 from ...utils import logging
-from .auto_factory import _BaseAutoModelClass, _LazyAutoMapping, auto_class_update
+from .auto_factory import _BaseAutoBackboneClass, _BaseAutoModelClass, _LazyAutoMapping, auto_class_update
 from .configuration_auto import CONFIG_MAPPING_NAMES
 
 
@@ -179,6 +179,7 @@ MODEL_MAPPING_NAMES = OrderedDict(
         ("tapas", "TapasModel"),
         ("time_series_transformer", "TimeSeriesTransformerModel"),
         ("timesformer", "TimesformerModel"),
+        ("timm_backbone", "TimmBackbone"),
         ("trajectory_transformer", "TrajectoryTransformerModel"),
         ("transfo-xl", "TransfoXLModel"),
         ("tvlt", "TvltModel"),
@@ -999,6 +1000,7 @@ MODEL_FOR_BACKBONE_MAPPING_NAMES = OrderedDict(
         ("nat", "NatBackbone"),
         ("resnet", "ResNetBackbone"),
         ("swin", "SwinBackbone"),
+        ("timm_backbone", "TimmBackbone"),
     ]
 )
 
@@ -1330,7 +1332,7 @@ class AutoModelForAudioXVector(_BaseAutoModelClass):
     _model_mapping = MODEL_FOR_AUDIO_XVECTOR_MAPPING
 
 
-class AutoBackbone(_BaseAutoModelClass):
+class AutoBackbone(_BaseAutoBackboneClass):
     _model_mapping = MODEL_FOR_BACKBONE_MAPPING
 
 

src/transformers/models/bit/modeling_bit.py

@@ -39,7 +39,7 @@ from ...utils import (
     logging,
     replace_return_docstrings,
 )
-from ...utils.backbone_utils import BackboneMixin, get_aligned_output_features_output_indices
+from ...utils.backbone_utils import BackboneMixin
 from .configuration_bit import BitConfig
 
 
@@ -845,14 +845,10 @@ class BitForImageClassification(BitPreTrainedModel):
 class BitBackbone(BitPreTrainedModel, BackboneMixin):
     def __init__(self, config):
         super().__init__(config)
+        super()._init_backbone(config)
 
-        self.stage_names = config.stage_names
         self.bit = BitModel(config)
-
         self.num_features = [config.embedding_size] + config.hidden_sizes
-        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
-            config.out_features, config.out_indices, self.stage_names
-        )
 
         # initialize weights and apply final processing
         self.post_init()

src/transformers/models/convnext/modeling_convnext.py

@@ -37,7 +37,7 @@ from ...utils import (
     logging,
     replace_return_docstrings,
 )
-from ...utils.backbone_utils import BackboneMixin, get_aligned_output_features_output_indices
+from ...utils.backbone_utils import BackboneMixin
 from .configuration_convnext import ConvNextConfig
 
 
@@ -481,15 +481,11 @@ class ConvNextForImageClassification(ConvNextPreTrainedModel):
 class ConvNextBackbone(ConvNextPreTrainedModel, BackboneMixin):
     def __init__(self, config):
         super().__init__(config)
+        super()._init_backbone(config)
 
-        self.stage_names = config.stage_names
         self.embeddings = ConvNextEmbeddings(config)
         self.encoder = ConvNextEncoder(config)
-
         self.num_features = [config.hidden_sizes[0]] + config.hidden_sizes
-        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
-            config.out_features, config.out_indices, self.stage_names
-        )
 
         # Add layer norms to hidden states of out_features
         hidden_states_norms = {}

src/transformers/models/convnextv2/modeling_convnextv2.py

@@ -37,7 +37,7 @@ from ...utils import (
     logging,
     replace_return_docstrings,
 )
-from ...utils.backbone_utils import BackboneMixin, get_aligned_output_features_output_indices
+from ...utils.backbone_utils import BackboneMixin
 from .configuration_convnextv2 import ConvNextV2Config
 
 
@@ -504,15 +504,11 @@ class ConvNextV2ForImageClassification(ConvNextV2PreTrainedModel):
 class ConvNextV2Backbone(ConvNextV2PreTrainedModel, BackboneMixin):
     def __init__(self, config):
         super().__init__(config)
+        super()._init_backbone(config)
 
-        self.stage_names = config.stage_names
         self.embeddings = ConvNextV2Embeddings(config)
         self.encoder = ConvNextV2Encoder(config)
-
         self.num_features = [config.hidden_sizes[0]] + config.hidden_sizes
-        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
-            config.out_features, config.out_indices, self.stage_names
-        )
 
         # Add layer norms to hidden states of out_features
         hidden_states_norms = {}

src/transformers/models/dinat/modeling_dinat.py

@@ -39,7 +39,7 @@ from ...utils import (
     replace_return_docstrings,
     requires_backends,
 )
-from ...utils.backbone_utils import BackboneMixin, get_aligned_output_features_output_indices
+from ...utils.backbone_utils import BackboneMixin
 from .configuration_dinat import DinatConfig
 
 
@@ -883,17 +883,12 @@ class DinatForImageClassification(DinatPreTrainedModel):
 class DinatBackbone(DinatPreTrainedModel, BackboneMixin):
     def __init__(self, config):
         super().__init__(config)
+        super()._init_backbone(config)
 
         requires_backends(self, ["natten"])
 
-        self.stage_names = config.stage_names
-
         self.embeddings = DinatEmbeddings(config)
         self.encoder = DinatEncoder(config)
-
-        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
-            config.out_features, config.out_indices, self.stage_names
-        )
         self.num_features = [config.embed_dim] + [int(config.embed_dim * 2**i) for i in range(len(config.depths))]
 
         # Add layer norms to hidden states of out_features

src/transformers/models/focalnet/modeling_focalnet.py

@@ -36,7 +36,7 @@ from ...utils import (
     logging,
     replace_return_docstrings,
 )
-from ...utils.backbone_utils import BackboneMixin, get_aligned_output_features_output_indices
+from ...utils.backbone_utils import BackboneMixin
 from .configuration_focalnet import FocalNetConfig
 
 
@@ -981,16 +981,12 @@ class FocalNetForImageClassification(FocalNetPreTrainedModel):
     FOCALNET_START_DOCSTRING,
 )
 class FocalNetBackbone(FocalNetPreTrainedModel, BackboneMixin):
-    def __init__(self, config):
+    def __init__(self, config: FocalNetConfig):
         super().__init__(config)
-
-        self.stage_names = config.stage_names
-        self.focalnet = FocalNetModel(config)
+        super()._init_backbone(config)
 
         self.num_features = [config.embed_dim] + config.hidden_sizes
-        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
-            config.out_features, config.out_indices, self.stage_names
-        )
+        self.focalnet = FocalNetModel(config)
 
         # initialize weights and apply final processing
         self.post_init()

src/transformers/models/maskformer/modeling_maskformer_swin.py

@@ -29,7 +29,7 @@ from ...file_utils import ModelOutput
 from ...modeling_outputs import BackboneOutput
 from ...modeling_utils import PreTrainedModel
 from ...pytorch_utils import find_pruneable_heads_and_indices, meshgrid, prune_linear_layer
-from ...utils.backbone_utils import BackboneMixin, get_aligned_output_features_output_indices
+from ...utils.backbone_utils import BackboneMixin
 from .configuration_maskformer_swin import MaskFormerSwinConfig
 
 
@@ -852,17 +852,11 @@ class MaskFormerSwinBackbone(MaskFormerSwinPreTrainedModel, BackboneMixin):
 
     def __init__(self, config: MaskFormerSwinConfig):
         super().__init__(config)
+        super()._init_backbone(config)
 
-        self.stage_names = config.stage_names
         self.model = MaskFormerSwinModel(config)
-
-        self._out_features = config.out_features if config.out_features is not None else [self.stage_names[-1]]
         if "stem" in self.out_features:
             raise ValueError("This backbone does not support 'stem' in the `out_features`.")
-
-        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
-            config.out_features, config.out_indices, self.stage_names
-        )
         self.num_features = [config.embed_dim] + [int(config.embed_dim * 2**i) for i in range(len(config.depths))]
         self.hidden_states_norms = nn.ModuleList(
             [nn.LayerNorm(num_channels) for num_channels in self.num_features[1:]]

src/transformers/models/nat/modeling_nat.py

@@ -39,7 +39,7 @@ from ...utils import (
     replace_return_docstrings,
     requires_backends,
 )
-from ...utils.backbone_utils import BackboneMixin, get_aligned_output_features_output_indices
+from ...utils.backbone_utils import BackboneMixin
 from .configuration_nat import NatConfig
 
 
@@ -861,17 +861,12 @@ class NatForImageClassification(NatPreTrainedModel):
 class NatBackbone(NatPreTrainedModel, BackboneMixin):
     def __init__(self, config):
         super().__init__(config)
+        super()._init_backbone(config)
 
         requires_backends(self, ["natten"])
 
-        self.stage_names = config.stage_names
-
         self.embeddings = NatEmbeddings(config)
         self.encoder = NatEncoder(config)
-
-        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
-            config.out_features, config.out_indices, self.stage_names
-        )
         self.num_features = [config.embed_dim] + [int(config.embed_dim * 2**i) for i in range(len(config.depths))]
 
         # Add layer norms to hidden states of out_features

src/transformers/models/resnet/modeling_resnet.py

@@ -36,7 +36,7 @@ from ...utils import (
     logging,
     replace_return_docstrings,
 )
-from ...utils.backbone_utils import BackboneMixin, get_aligned_output_features_output_indices
+from ...utils.backbone_utils import BackboneMixin
 from .configuration_resnet import ResNetConfig
 
 
@@ -432,16 +432,12 @@ class ResNetForImageClassification(ResNetPreTrainedModel):
 class ResNetBackbone(ResNetPreTrainedModel, BackboneMixin):
     def __init__(self, config):
         super().__init__(config)
+        super()._init_backbone(config)
 
-        self.stage_names = config.stage_names
+        self.num_features = [config.embedding_size] + config.hidden_sizes
         self.embedder = ResNetEmbeddings(config)
         self.encoder = ResNetEncoder(config)
 
-        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
-            config.out_features, config.out_indices, self.stage_names
-        )
-        self.num_features = [config.embedding_size] + config.hidden_sizes
-
         # initialize weights and apply final processing
         self.post_init()
 

src/transformers/models/swin/modeling_swin.py

@@ -38,7 +38,7 @@ from ...utils import (
     logging,
     replace_return_docstrings,
 )
-from ...utils.backbone_utils import BackboneMixin, get_aligned_output_features_output_indices
+from ...utils.backbone_utils import BackboneMixin
 from .configuration_swin import SwinConfig
 
 
@@ -1259,17 +1259,12 @@ class SwinForImageClassification(SwinPreTrainedModel):
 class SwinBackbone(SwinPreTrainedModel, BackboneMixin):
     def __init__(self, config: SwinConfig):
         super().__init__(config)
+        super()._init_backbone(config)
 
-        self.stage_names = config.stage_names
-
+        self.num_features = [config.embed_dim] + [int(config.embed_dim * 2**i) for i in range(len(config.depths))]
         self.embeddings = SwinEmbeddings(config)
         self.encoder = SwinEncoder(config, self.embeddings.patch_grid)
 
-        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
-            config.out_features, config.out_indices, self.stage_names
-        )
-        self.num_features = [config.embed_dim] + [int(config.embed_dim * 2**i) for i in range(len(config.depths))]
-
         # Add layer norms to hidden states of out_features
         hidden_states_norms = {}
         for stage, num_channels in zip(self._out_features, self.channels):

src/transformers/models/timm_backbone/__init__.py

@@ -0,0 +1,49 @@
+# flake8: noqa
+# There's no way to ignore "F401 '...' imported but unused" warnings in this
+# module, but to preserve other warnings. So, don't check this module at all.
+
+# Copyright 2023 The HuggingFace Team. All rights reserved.
+#
+# 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.
+from typing import TYPE_CHECKING
+
+from ...utils import OptionalDependencyNotAvailable, _LazyModule, is_torch_available
+
+
+_import_structure = {"configuration_timm_backbone": ["TimmBackboneConfig"]}
+
+
+try:
+    if not is_torch_available():
+        raise OptionalDependencyNotAvailable()
+except OptionalDependencyNotAvailable:
+    pass
+else:
+    _import_structure["modeling_timm_backbone"] = ["TimmBackbone"]
+
+
+if TYPE_CHECKING:
+    from .configuration_timm_backbone import TimmBackboneConfig
+
+    try:
+        if not is_torch_available():
+            raise OptionalDependencyNotAvailable()
+    except OptionalDependencyNotAvailable:
+        pass
+    else:
+        from .modeling_timm_backbone import TimmBackbone
+
+else:
+    import sys
+
+    sys.modules[__name__] = _LazyModule(__name__, globals()["__file__"], _import_structure, module_spec=__spec__)

src/transformers/models/timm_backbone/configuration_timm_backbone.py

@@ -0,0 +1,78 @@
+# coding=utf-8
+# Copyright 2023 The HuggingFace Inc. team. All rights reserved.
+#
+# 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.
+
+""" Configuration for Backbone models"""
+
+from ...configuration_utils import PretrainedConfig
+from ...utils import logging
+
+
+logger = logging.get_logger(__name__)
+
+
+class TimmBackboneConfig(PretrainedConfig):
+    r"""
+    This is the configuration class to store the configuration for a timm backbone [`TimmBackbone`].
+
+    It is used to instantiate a timm backbone model according to the specified arguments, defining the model.
+
+    Configuration objects inherit from [`PretrainedConfig`] and can be used to control the model outputs. Read the
+    documentation from [`PretrainedConfig`] for more information.
+
+    Args:
+        backbone (`str`, *optional*):
+            The timm checkpoint to load.
+        num_channels (`int`, *optional*, defaults to 3):
+            The number of input channels.
+        features_only (`bool`, *optional*, defaults to `True`):
+            Whether to output only the features or also the logits.
+        use_pretrained_backbone (`bool`, *optional*, defaults to `True`):
+            Whether to use a pretrained backbone.
+        out_indices (`List[int]`, *optional*):
+            If used as backbone, list of indices of features to output. Can be any of 0, 1, 2, etc. (depending on how
+            many stages the model has). Will default to the last stage if unset.
+
+    Example:
+    ```python
+    >>> from transformers import TimmBackboneConfig, TimmBackbone
+
+    >>> # Initializing a timm backbone
+    >>> configuration = TimmBackboneConfig("resnet50")
+
+    >>> # Initializing a model from the configuration
+    >>> model = TimmBackbone(configuration)
+
+    >>> # Accessing the model configuration
+    >>> configuration = model.config
+    ```
+    """
+    model_type = "timm_backbone"
+
+    def __init__(
+        self,
+        backbone=None,
+        num_channels=3,
+        features_only=True,
+        use_pretrained_backbone=True,
+        out_indices=None,
+        **kwargs,
+    ):
+        super().__init__(**kwargs)
+        self.backbone = backbone
+        self.num_channels = num_channels
+        self.features_only = features_only
+        self.use_pretrained_backbone = use_pretrained_backbone
+        self.use_timm_backbone = True
+        self.out_indices = out_indices if out_indices is not None else (-1,)

src/transformers/models/timm_backbone/modeling_timm_backbone.py

@@ -0,0 +1,140 @@
+# coding=utf-8
+# Copyright 2023 The HuggingFace Inc. team. All rights reserved.
+#
+# 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.
+
+from typing import Tuple, Union
+
+from ...modeling_outputs import BackboneOutput
+from ...modeling_utils import PreTrainedModel
+from ...utils import is_timm_available, is_torch_available, requires_backends
+from ...utils.backbone_utils import BackboneMixin
+from .configuration_timm_backbone import TimmBackboneConfig
+
+
+if is_timm_available():
+    import timm
+
+
+if is_torch_available():
+    from torch import Tensor
+
+
+class TimmBackbone(PreTrainedModel, BackboneMixin):
+    """
+    Wrapper class for timm models to be used as backbones. This enables using the timm models interchangeably with the
+    other models in the library keeping the same API.
+    """
+
+    main_input_name = "pixel_values"
+    supports_gradient_checkpointing = False
+    config_class = TimmBackboneConfig
+
+    def __init__(self, config, **kwargs):
+        requires_backends(self, "timm")
+        super().__init__(config)
+        self.config = config
+
+        if config.backbone is None:
+            raise ValueError("backbone is not set in the config. Please set it to a timm model name.")
+
+        if config.backbone not in timm.list_models():
+            raise ValueError(f"backbone {config.backbone} is not supported by timm.")
+
+        if hasattr(config, "out_features") and config.out_features is not None:
+            raise ValueError("out_features is not supported by TimmBackbone. Please use out_indices instead.")
+
+        pretrained = getattr(config, "use_pretrained_backbone", None)
+        if pretrained is None:
+            raise ValueError("use_pretrained_backbone is not set in the config. Please set it to True or False.")
+
+        # We just take the final layer by default. This matches the default for the transformers models.
+        out_indices = config.out_indices if getattr(config, "out_indices", None) is not None else (-1,)
+
+        self._backbone = timm.create_model(
+            config.backbone,
+            pretrained=pretrained,
+            # This is currently not possible for transformer architectures.
+            features_only=config.features_only,
+            in_chans=config.num_channels,
+            out_indices=out_indices,
+            **kwargs,
+        )
+        # These are used to control the output of the model when called. If output_hidden_states is True, then
+        # return_layers is modified to include all layers.
+        self._return_layers = self._backbone.return_layers
+        self._all_layers = {layer["module"]: str(i) for i, layer in enumerate(self._backbone.feature_info.info)}
+        super()._init_backbone(config)
+
+    @classmethod
+    def from_pretrained(cls, pretrained_model_name_or_path, *model_args, **kwargs):
+        requires_backends(cls, ["vision", "timm"])
+        from ...models.timm_backbone import TimmBackboneConfig
+
+        config = kwargs.pop("config", TimmBackboneConfig())
+
+        use_timm = kwargs.pop("use_timm_backbone", True)
+        if not use_timm:
+            raise ValueError("use_timm_backbone must be True for timm backbones")
+
+        num_channels = kwargs.pop("num_channels", config.num_channels)
+        features_only = kwargs.pop("features_only", config.features_only)
+        use_pretrained_backbone = kwargs.pop("use_pretrained_backbone", config.use_pretrained_backbone)
+        out_indices = kwargs.pop("out_indices", config.out_indices)
+        config = TimmBackboneConfig(
+            backbone=pretrained_model_name_or_path,
+            num_channels=num_channels,
+            features_only=features_only,
+            use_pretrained_backbone=use_pretrained_backbone,
+            out_indices=out_indices,
+        )
+        return super()._from_config(config, **kwargs)
+
+    def _init_weights(self, module):
+        """
+        Empty init weights function to ensure compatibility of the class in the library.
+        """
+        pass
+
+    def forward(
+        self, pixel_values, output_attentions=None, output_hidden_states=None, return_dict=None, **kwargs
+    ) -> Union[BackboneOutput, Tuple[Tensor, ...]]:
+        return_dict = return_dict if return_dict is not None else self.config.use_return_dict
+        output_hidden_states = (
+            output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
+        )
+        output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
+
+        if output_attentions:
+            raise ValueError("Cannot output attentions for timm backbones at the moment")
+
+        if output_hidden_states:
+            # We modify the return layers to include all the stages of the backbone
+            self._backbone.return_layers = self._all_layers
+            hidden_states = self._backbone(pixel_values, **kwargs)
+            self._backbone.return_layers = self._return_layers
+            feature_maps = tuple(hidden_states[i] for i in self.out_indices)
+        else:
+            feature_maps = self._backbone(pixel_values, **kwargs)
+            hidden_states = None
+
+        feature_maps = tuple(feature_maps)
+        hidden_states = tuple(hidden_states) if hidden_states is not None else None
+
+        if not return_dict:
+            output = (feature_maps,)
+            if output_hidden_states:
+                output = output + (hidden_states,)
+            return output
+
+        return BackboneOutput(feature_maps=feature_maps, hidden_states=hidden_states, attentions=None)

src/transformers/utils/backbone_utils.py

@@ -15,10 +15,16 @@
 
 """ Collection of utils to be used by backbones and their components."""
 
+import enum
 import inspect
 from typing import Iterable, List, Optional, Tuple, Union
 
 
+class BackboneType(enum.Enum):
+    TIMM = "timm"
+    TRANSFORMERS = "transformers"
+
+
 def verify_out_features_out_indices(
     out_features: Optional[Iterable[str]], out_indices: Optional[Iterable[int]], stage_names: Optional[Iterable[str]]
 ):
@@ -72,7 +78,7 @@ def _align_output_features_output_indices(
         out_indices = [len(stage_names) - 1]
         out_features = [stage_names[-1]]
     elif out_indices is None and out_features is not None:
-        out_indices = [stage_names.index(layer) for layer in stage_names if layer in out_features]
+        out_indices = [stage_names.index(layer) for layer in out_features]
     elif out_features is None and out_indices is not None:
         out_features = [stage_names[idx] for idx in out_indices]
     return out_features, out_indices
@@ -110,29 +116,57 @@ def get_aligned_output_features_output_indices(
 
 
 class BackboneMixin:
-    @property
-    def out_feature_channels(self):
-        # the current backbones will output the number of channels for each stage
-        # even if that stage is not in the out_features list.
-        return {stage: self.num_features[i] for i, stage in enumerate(self.stage_names)}
+    backbone_type: Optional[BackboneType] = None
 
-    @property
-    def channels(self):
-        return [self.out_feature_channels[name] for name in self.out_features]
+    def _init_timm_backbone(self, config) -> None:
+        """
+        Initialize the backbone model from timm The backbone must already be loaded to self._backbone
+        """
+        if getattr(self, "_backbone", None) is None:
+            raise ValueError("self._backbone must be set before calling _init_timm_backbone")
 
-    def forward_with_filtered_kwargs(self, *args, **kwargs):
-        signature = dict(inspect.signature(self.forward).parameters)
-        filtered_kwargs = {k: v for k, v in kwargs.items() if k in signature}
-        return self(*args, **filtered_kwargs)
+        # These will diagree with the defaults for the transformers models e.g. for resnet50
+        # the transformer model has out_features = ['stem', 'stage1', 'stage2', 'stage3', 'stage4']
+        # the timm model has out_features = ['act', 'layer1', 'layer2', 'layer3', 'layer4']
+        self.stage_names = [stage["module"] for stage in self._backbone.feature_info.info]
+        self.num_features = [stage["num_chs"] for stage in self._backbone.feature_info.info]
+        out_indices = self._backbone.feature_info.out_indices
+        out_features = self._backbone.feature_info.module_name()
 
-    def forward(
-        self,
-        pixel_values,
-        output_hidden_states: Optional[bool] = None,
-        output_attentions: Optional[bool] = None,
-        return_dict: Optional[bool] = None,
-    ):
-        raise NotImplementedError("This method should be implemented by the derived class.")
+        # We verify the out indices and out features are valid
+        verify_out_features_out_indices(
+            out_features=out_features, out_indices=out_indices, stage_names=self.stage_names
+        )
+        self._out_features, self._out_indices = out_features, out_indices
+
+    def _init_transformers_backbone(self, config) -> None:
+        stage_names = getattr(config, "stage_names")
+        out_features = getattr(config, "out_features", None)
+        out_indices = getattr(config, "out_indices", None)
+
+        self.stage_names = stage_names
+        self._out_features, self._out_indices = get_aligned_output_features_output_indices(
+            out_features=out_features, out_indices=out_indices, stage_names=stage_names
+        )
+        # Number of channels for each stage. This is set in the transformer backbone model init
+        self.num_features = None
+
+    def _init_backbone(self, config) -> None:
+        """
+        Method to initialize the backbone. This method is called by the constructor of the base class after the
+        pretrained model weights have been loaded.
+        """
+        self.config = config
+
+        self.use_timm_backbone = getattr(config, "use_timm_backbone", False)
+        self.backbone_type = BackboneType.TIMM if self.use_timm_backbone else BackboneType.TRANSFORMERS
+
+        if self.backbone_type == BackboneType.TIMM:
+            self._init_timm_backbone(config)
+        elif self.backbone_type == BackboneType.TRANSFORMERS:
+            self._init_transformers_backbone(config)
+        else:
+            raise ValueError(f"backbone_type {self.backbone_type} not supported.")
 
     @property
     def out_features(self):
@@ -160,6 +194,40 @@ class BackboneMixin:
             out_features=None, out_indices=out_indices, stage_names=self.stage_names
         )
 
+    @property
+    def out_feature_channels(self):
+        # the current backbones will output the number of channels for each stage
+        # even if that stage is not in the out_features list.
+        return {stage: self.num_features[i] for i, stage in enumerate(self.stage_names)}
+
+    @property
+    def channels(self):
+        return [self.out_feature_channels[name] for name in self.out_features]
+
+    def forward_with_filtered_kwargs(self, *args, **kwargs):
+        signature = dict(inspect.signature(self.forward).parameters)
+        filtered_kwargs = {k: v for k, v in kwargs.items() if k in signature}
+        return self(*args, **filtered_kwargs)
+
+    def forward(
+        self,
+        pixel_values,
+        output_hidden_states: Optional[bool] = None,
+        output_attentions: Optional[bool] = None,
+        return_dict: Optional[bool] = None,
+    ):
+        raise NotImplementedError("This method should be implemented by the derived class.")
+
+    def to_dict(self):
+        """
+        Serializes this instance to a Python dictionary. Override the default `to_dict()` from `PretrainedConfig` to
+        include the `out_features` and `out_indices` attributes.
+        """
+        output = super().to_dict()
+        output["out_features"] = output.pop("_out_features")
+        output["out_indices"] = output.pop("_out_indices")
+        return output
+
 
 class BackboneConfigMixin:
     """

src/transformers/utils/dummy_pt_objects.py

@@ -6806,6 +6806,13 @@ class TimesformerPreTrainedModel(metaclass=DummyObject):
         requires_backends(self, ["torch"])
 
 
+class TimmBackbone(metaclass=DummyObject):
+    _backends = ["torch"]
+
+    def __init__(self, *args, **kwargs):
+        requires_backends(self, ["torch"])
+
+
 TRAJECTORY_TRANSFORMER_PRETRAINED_MODEL_ARCHIVE_LIST = None
 
 

tests/models/auto/test_modeling_auto.py

@@ -45,6 +45,7 @@ if is_torch_available():
     from test_module.custom_modeling import CustomModel
 
     from transformers import (
+        AutoBackbone,
         AutoConfig,
         AutoModel,
         AutoModelForCausalLM,
@@ -66,11 +67,13 @@ if is_torch_available():
         FunnelModel,
         GPT2Config,
         GPT2LMHeadModel,
+        ResNetBackbone,
         RobertaForMaskedLM,
         T5Config,
         T5ForConditionalGeneration,
         TapasConfig,
         TapasForQuestionAnswering,
+        TimmBackbone,
     )
     from transformers.models.auto.modeling_auto import (
         MODEL_FOR_CAUSAL_LM_MAPPING,
@@ -224,6 +227,42 @@ class AutoModelTest(unittest.TestCase):
             self.assertIsNotNone(model)
             self.assertIsInstance(model, BertForTokenClassification)
 
+    @slow
+    def test_auto_backbone_timm_model_from_pretrained(self):
+        # Configs can't be loaded for timm models
+        model = AutoBackbone.from_pretrained("resnet18", use_timm_backbone=True)
+
+        with pytest.raises(ValueError):
+            # We can't pass output_loading_info=True as we're loading from timm
+            AutoBackbone.from_pretrained("resnet18", use_timm_backbone=True, output_loading_info=True)
+
+        self.assertIsNotNone(model)
+        self.assertIsInstance(model, TimmBackbone)
+
+        # Check kwargs are correctly passed to the backbone
+        model = AutoBackbone.from_pretrained("resnet18", use_timm_backbone=True, out_indices=(-1, -2))
+        self.assertEqual(model.out_indices, (-1, -2))
+
+        # Check out_features cannot be passed to Timm backbones
+        with self.assertRaises(ValueError):
+            _ = AutoBackbone.from_pretrained("resnet18", use_timm_backbone=True, out_features=["stage1"])
+
+    @slow
+    def test_auto_backbone_from_pretrained(self):
+        model = AutoBackbone.from_pretrained("microsoft/resnet-18")
+        model, loading_info = AutoBackbone.from_pretrained("microsoft/resnet-18", output_loading_info=True)
+        self.assertIsNotNone(model)
+        self.assertIsInstance(model, ResNetBackbone)
+
+        # Check kwargs are correctly passed to the backbone
+        model = AutoBackbone.from_pretrained("microsoft/resnet-18", out_indices=[-1, -2])
+        self.assertEqual(model.out_indices, [-1, -2])
+        self.assertEqual(model.out_features, ["stage4", "stage3"])
+
+        model = AutoBackbone.from_pretrained("microsoft/resnet-18", out_features=["stage2", "stage4"])
+        self.assertEqual(model.out_indices, [2, 4])
+        self.assertEqual(model.out_features, ["stage2", "stage4"])
+
     def test_from_pretrained_identifier(self):
         model = AutoModelWithLMHead.from_pretrained(SMALL_MODEL_IDENTIFIER)
         self.assertIsInstance(model, BertForMaskedLM)

tests/models/timm_backbone/test_modeling_timm_backbone.py

@@ -0,0 +1,259 @@
+# coding=utf-8
+# Copyright 2023 The HuggingFace Inc. team. All rights reserved.
+#
+# 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 copy
+import inspect
+import unittest
+
+from transformers import AutoBackbone
+from transformers.configuration_utils import PretrainedConfig
+from transformers.testing_utils import require_timm, require_torch, torch_device
+from transformers.utils.import_utils import is_torch_available
+
+from ...test_backbone_common import BackboneTesterMixin
+from ...test_configuration_common import ConfigTester
+from ...test_modeling_common import ModelTesterMixin, floats_tensor
+
+
+if is_torch_available():
+    import torch
+
+    from transformers import TimmBackbone, TimmBackboneConfig
+
+
+class TimmBackboneModelTester:
+    def __init__(
+        self,
+        parent,
+        out_indices=None,
+        out_features=None,
+        stage_names=None,
+        backbone="resnet50",
+        batch_size=3,
+        image_size=32,
+        num_channels=3,
+        is_training=True,
+        use_pretrained_backbone=True,
+    ):
+        self.parent = parent
+        self.out_indices = out_indices if out_indices is not None else [4]
+        self.stage_names = stage_names
+        self.out_features = out_features
+        self.backbone = backbone
+        self.batch_size = batch_size
+        self.image_size = image_size
+        self.num_channels = num_channels
+        self.use_pretrained_backbone = use_pretrained_backbone
+        self.is_training = is_training
+
+    def prepare_config_and_inputs(self):
+        pixel_values = floats_tensor([self.batch_size, self.num_channels, self.image_size, self.image_size])
+        config = self.get_config()
+
+        return config, pixel_values
+
+    def get_config(self):
+        return TimmBackboneConfig(
+            image_size=self.image_size,
+            num_channels=self.num_channels,
+            out_features=self.out_features,
+            out_indices=self.out_indices,
+            stage_names=self.stage_names,
+            use_pretrained_backbone=self.use_pretrained_backbone,
+            backbone=self.backbone,
+        )
+
+    def create_and_check_model(self, config, pixel_values):
+        model = TimmBackbone(config=config)
+        model.to(torch_device)
+        model.eval()
+        with torch.no_grad():
+            result = model(pixel_values)
+        self.parent.assertEqual(
+            result.feature_map[-1].shape,
+            (self.batch_size, model.channels[-1], 14, 14),
+        )
+
+    def prepare_config_and_inputs_for_common(self):
+        config_and_inputs = self.prepare_config_and_inputs()
+        config, pixel_values = config_and_inputs
+        inputs_dict = {"pixel_values": pixel_values}
+        return config, inputs_dict
+
+
+@require_torch
+@require_timm
+class TimmBackboneModelTest(ModelTesterMixin, BackboneTesterMixin, unittest.TestCase):
+    all_model_classes = (TimmBackbone,) if is_torch_available() else ()
+    test_resize_embeddings = False
+    test_head_masking = False
+    test_pruning = False
+    has_attentions = False
+
+    def setUp(self):
+        self.model_tester = TimmBackboneModelTester(self)
+        self.config_tester = ConfigTester(self, config_class=PretrainedConfig, has_text_modality=False)
+
+    def test_config(self):
+        self.config_tester.create_and_test_config_to_json_string()
+        self.config_tester.create_and_test_config_to_json_file()
+        self.config_tester.create_and_test_config_from_and_save_pretrained()
+        self.config_tester.create_and_test_config_with_num_labels()
+        self.config_tester.check_config_can_be_init_without_params()
+        self.config_tester.check_config_arguments_init()
+
+    def test_timm_transformer_backbone_equivalence(self):
+        timm_checkpoint = "resnet18"
+        transformers_checkpoint = "microsoft/resnet-18"
+
+        timm_model = AutoBackbone.from_pretrained(timm_checkpoint, use_timm_backbone=True)
+        transformers_model = AutoBackbone.from_pretrained(transformers_checkpoint)
+
+        self.assertEqual(len(timm_model.out_features), len(transformers_model.out_features))
+        self.assertEqual(len(timm_model.stage_names), len(transformers_model.stage_names))
+        self.assertEqual(timm_model.channels, transformers_model.channels)
+        # Out indices are set to the last layer by default. For timm models, we don't know
+        # the number of layers in advance, so we set it to (-1,), whereas for transformers
+        # models, we set it to [len(stage_names) - 1] (kept for backward compatibility).
+        self.assertEqual(timm_model.out_indices, (-1,))
+        self.assertEqual(transformers_model.out_indices, [len(timm_model.stage_names) - 1])
+
+        timm_model = AutoBackbone.from_pretrained(timm_checkpoint, use_timm_backbone=True, out_indices=[1, 2, 3])
+        transformers_model = AutoBackbone.from_pretrained(transformers_checkpoint, out_indices=[1, 2, 3])
+
+        self.assertEqual(timm_model.out_indices, transformers_model.out_indices)
+        self.assertEqual(len(timm_model.out_features), len(transformers_model.out_features))
+        self.assertEqual(timm_model.channels, transformers_model.channels)
+
+    @unittest.skip("TimmBackbone doesn't support feed forward chunking")
+    def test_feed_forward_chunking(self):
+        pass
+
+    @unittest.skip("TimmBackbone doesn't have num_hidden_layers attribute")
+    def test_hidden_states_output(self):
+        pass
+
+    @unittest.skip("TimmBackbone initialization is managed on the timm side")
+    def test_initialization(self):
+        pass
+
+    @unittest.skip("TimmBackbone models doesn't have inputs_embeds")
+    def test_inputs_embeds(self):
+        pass
+
+    @unittest.skip("TimmBackbone models doesn't have inputs_embeds")
+    def test_model_common_attributes(self):
+        pass
+
+    @unittest.skip("TimmBackbone model cannot be created without specifying a backbone checkpoint")
+    def test_from_pretrained_no_checkpoint(self):
+        pass
+
+    @unittest.skip("Only checkpoints on timm can be loaded into TimmBackbone")
+    def test_save_load(self):
+        pass
+
+    @unittest.skip("model weights aren't tied in TimmBackbone.")
+    def test_tie_model_weights(self):
+        pass
+
+    @unittest.skip("model weights aren't tied in TimmBackbone.")
+    def test_tied_model_weights_key_ignore(self):
+        pass
+
+    @unittest.skip("TimmBackbone doesn't have hidden size info in its configuration.")
+    def test_channels(self):
+        pass
+
+    @unittest.skip("TimmBackbone doesn't support output_attentions.")
+    def test_torchscript_output_attentions(self):
+        pass
+
+    @unittest.skip("Safetensors is not supported by timm.")
+    def test_can_use_safetensors(self):
+        pass
+
+    def test_forward_signature(self):
+        config, _ = self.model_tester.prepare_config_and_inputs_for_common()
+
+        for model_class in self.all_model_classes:
+            model = model_class(config)
+            signature = inspect.signature(model.forward)
+            # signature.parameters is an OrderedDict => so arg_names order is deterministic
+            arg_names = [*signature.parameters.keys()]
+
+            expected_arg_names = ["pixel_values"]
+            self.assertListEqual(arg_names[:1], expected_arg_names)
+
+    def test_retain_grad_hidden_states_attentions(self):
+        config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
+        config.output_hidden_states = True
+        config.output_attentions = self.has_attentions
+
+        # no need to test all models as different heads yield the same functionality
+        model_class = self.all_model_classes[0]
+        model = model_class(config)
+        model.to(torch_device)
+
+        inputs = self._prepare_for_class(inputs_dict, model_class)
+        outputs = model(**inputs)
+        output = outputs[0][-1]
+
+        # Encoder-/Decoder-only models
+        hidden_states = outputs.hidden_states[0]
+        hidden_states.retain_grad()
+
+        if self.has_attentions:
+            attentions = outputs.attentions[0]
+            attentions.retain_grad()
+
+        output.flatten()[0].backward(retain_graph=True)
+
+        self.assertIsNotNone(hidden_states.grad)
+
+        if self.has_attentions:
+            self.assertIsNotNone(attentions.grad)
+
+    # TimmBackbone config doesn't have out_features attribute
+    def test_create_from_modified_config(self):
+        config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
+
+        for model_class in self.all_model_classes:
+            model = model_class(config)
+            model.to(torch_device)
+            model.eval()
+            result = model(**inputs_dict)
+
+            self.assertEqual(len(result.feature_maps), len(config.out_indices))
+            self.assertEqual(len(model.channels), len(config.out_indices))
+
+            # Check output of last stage is taken if out_features=None, out_indices=None
+            modified_config = copy.deepcopy(config)
+            modified_config.out_indices = None
+            model = model_class(modified_config)
+            model.to(torch_device)
+            model.eval()
+            result = model(**inputs_dict)
+
+            self.assertEqual(len(result.feature_maps), 1)
+            self.assertEqual(len(model.channels), 1)
+
+            # Check backbone can be initialized with fresh weights
+            modified_config = copy.deepcopy(config)
+            modified_config.use_pretrained_backbone = False
+            model = model_class(modified_config)
+            model.to(torch_device)
+            model.eval()
+            result = model(**inputs_dict)

tests/test_backbone_common.py

@@ -17,6 +17,7 @@ import copy
 import inspect
 
 from transformers.testing_utils import require_torch, torch_device
+from transformers.utils.backbone_utils import BackboneType
 
 
 @require_torch
@@ -104,6 +105,8 @@ class BackboneTesterMixin:
 
             self.assertEqual(len(result.feature_maps), len(config.out_features))
             self.assertEqual(len(model.channels), len(config.out_features))
+            self.assertEqual(len(result.feature_maps), len(config.out_indices))
+            self.assertEqual(len(model.channels), len(config.out_indices))
 
             # Check output of last stage is taken if out_features=None, out_indices=None
             modified_config = copy.deepcopy(config)
@@ -140,6 +143,7 @@ class BackboneTesterMixin:
         for backbone_class in self.all_model_classes:
             backbone = backbone_class(config)
 
+            self.assertTrue(hasattr(backbone, "backbone_type"))
             self.assertTrue(hasattr(backbone, "stage_names"))
             self.assertTrue(hasattr(backbone, "num_features"))
             self.assertTrue(hasattr(backbone, "out_indices"))
@@ -147,6 +151,7 @@ class BackboneTesterMixin:
             self.assertTrue(hasattr(backbone, "out_feature_channels"))
             self.assertTrue(hasattr(backbone, "channels"))
 
+            self.assertIsInstance(backbone.backbone_type, BackboneType)
             # Verify num_features has been initialized in the backbone init
             self.assertIsNotNone(backbone.num_features)
             self.assertTrue(len(backbone.channels) == len(backbone.out_indices))

utils/check_config_attributes.py

@@ -77,6 +77,7 @@ SPECIAL_CASES_TO_ALLOW = {
     "AutoformerConfig": ["num_static_real_features", "num_time_features"],
 }
 
+
 # TODO (ydshieh): Check the failing cases, try to fix them or move some cases to the above block once we are sure
 SPECIAL_CASES_TO_ALLOW.update(
     {
@@ -172,6 +173,8 @@ def check_attribute_being_used(config_class, attributes, default_value, source_s
         "mask_index",
         "image_size",
         "use_cache",
+        "out_features",
+        "out_indices",
     ]
     attributes_used_in_generation = ["encoder_no_repeat_ngram_size"]
 

utils/check_config_docstrings.py

@@ -39,6 +39,7 @@ CONFIG_CLASSES_TO_IGNORE_FOR_DOCSTRING_CHECKPOINT_CHECK = {
     "EncoderDecoderConfig",
     "RagConfig",
     "SpeechEncoderDecoderConfig",
+    "TimmBackboneConfig",
     "VisionEncoderDecoderConfig",
     "VisionTextDualEncoderConfig",
     "LlamaConfig",

utils/check_copies.py

@@ -517,6 +517,7 @@ MODELS_NOT_IN_README = [
     "Speech Encoder decoder",
     "Speech2Text",
     "Speech2Text2",
+    "TimmBackbone",
     "Vision Encoder decoder",
     "VisionTextDualEncoder",
 ]

utils/check_repo.py

@@ -408,6 +408,7 @@ def get_model_modules():
         "modeling_speech_encoder_decoder",
         "modeling_flax_speech_encoder_decoder",
         "modeling_flax_vision_encoder_decoder",
+        "modeling_timm_backbone",
         "modeling_transfo_xl_utilities",
         "modeling_tf_auto",
         "modeling_tf_encoder_decoder",
@@ -846,6 +847,8 @@ SHOULD_HAVE_THEIR_OWN_PAGE = [
     "NatBackbone",
     "ResNetBackbone",
     "SwinBackbone",
+    "TimmBackbone",
+    "TimmBackboneConfig",
 ]