def __init__(
self,
arch: str = "resnet18",
pretrained: bool = True,
frozen: bool = True,
pooling: str = None,
pooling_kwargs: dict = None,
cut_layers: int = 2,
state_dict: Union[dict, str, Path] = None,
):
"""
Args:
arch: Name for resnet. Have to be one of
resnet18, resnet34, resnet50, resnet101, resnet152
pretrained: If True, returns a model pre-trained on ImageNet
frozen: If frozen, sets requires_grad to False
pooling: pooling
pooling_kwargs: params for pooling
state_dict (Union[dict, str, Path]): Path to ``torch.Model``
or a dict containing parameters and persistent buffers.
"""
super().__init__()
resnet = torchvision.models.__dict__[arch](pretrained=pretrained)
if state_dict is not None:
if isinstance(state_dict, (Path, str)):
state_dict = torch.load(str(state_dict))
resnet.load_state_dict(state_dict)
modules = list(resnet.children())[:-cut_layers] # delete last layers
if frozen:
for module in modules:
utils.set_requires_grad(module, requires_grad=False)
if pooling is not None:
pooling_kwargs = pooling_kwargs or {}
pooling_layer_fn = MODULE.get(pooling)
pooling_layer = (
pooling_layer_fn(
in_features=resnet.fc.in_features, **pooling_kwargs
)
if "attn" in pooling.lower()
else pooling_layer_fn(**pooling_kwargs)
)
modules += [pooling_layer]
if hasattr(pooling_layer, "out_features"):
out_features = pooling_layer.out_features(
in_features=resnet.fc.in_features
)
else:
out_features = None
else:
out_features = resnet.fc.in_features
modules += [Flatten()]
self.out_features = out_features
self.encoder = nn.Sequential(*modules)
class EncoderDecoderNet(nn.Module):
"""Generalized Encoder-Decoder network.
Args:
encoder: Encoder module, usually used for the extraction
of embeddings from input signals.
decoder: Decoder module, usually used for embeddings processing
e.g. generation of signal similar to the input one (in GANs).
"""
def __init__(self, encoder: nn.Module, decoder: nn.Module) -> None:
super().__init__()
self.encoder = encoder
self.decoder = decoder
def forward(self, x: torch.Tensor) -> torch.Tensor:
"""Forward pass method.
Args:
x: Batch of input signals e.g. images.
Returns:
Batch of generated signals e.g. images.
"""
x = self.encoder(x)
x = self.decoder(x)
x = torch.clamp(x, min=0.0, max=1.0)
return x
@classmethod
def get_from_params(
cls,
encoder_params: Optional[dict] = None,
decoder_params: Optional[dict] = None,
) -> "EncoderDecoderNet":
"""Create model based on it config.
Args:
encoder_params: Encoder module params.
decoder_params: Decoder module parameters.
Returns:
Model.
"""
encoder: nn.Module = nn.Identity()
if (encoder_params_ := copy.deepcopy(encoder_params)) is not None:
encoder_fn = MODULE.get(encoder_params_.pop("module"))
encoder = encoder_fn(**encoder_params_)
decoder: nn.Module = nn.Identity()
if (decoder_params_ := copy.deepcopy(decoder_params)) is not None:
decoder_fn = MODULE.get(decoder_params_.pop("module"))
decoder = decoder_fn(**decoder_params_)
def _process_fn_params(params: ModuleParams,
key: Optional[str] = None) -> Callable[..., nn.Module]:
module_fn: Callable[..., nn.Module]
if callable(params):
module_fn = params
elif isinstance(params, str):
name = params
module_fn = MODULE.get(name)
elif isinstance(params, dict) and key is not None:
params = copy.deepcopy(params)
name_or_fn = params.pop(key)
module_fn = _process_fn_params(name_or_fn)
module_fn = functools.partial(module_fn, **params)
else:
NotImplementedError()
return module_fn
def get_from_params(
cls,
encoder_params: Optional[dict] = None,
decoder_params: Optional[dict] = None,
) -> "EncoderDecoderNet":
"""Create model based on it config.
Args:
encoder_params: Encoder module params.
decoder_params: Decoder module parameters.
Returns:
Model.
"""
encoder: nn.Module = nn.Identity()
if (encoder_params_ := copy.deepcopy(encoder_params)) is not None:
encoder_fn = MODULE.get(encoder_params_.pop("module"))
encoder = encoder_fn(**encoder_params_)
def get_from_params(
cls,
encoder_params: Optional[dict] = None,
pooling_params: Optional[dict] = None,
head_params: Optional[dict] = None,
) -> "VGGConv":
"""Create model based on it config.
Args:
encoder_params: Params of encoder module.
pooling_params: Params of the pooling layer.
head_params: 'Head' module params.
Returns:
Model.
"""
encoder: nn.Module = nn.Identity()
if (encoder_params_ := copy.deepcopy(encoder_params)) is not None:
encoder_fn = MODULE.get(encoder_params_.pop("module"))
encoder = encoder_fn(**encoder_params_)
class VGGConv(nn.Module):
"""VGG-like neural network for image classification.
Args:
encoder: Image encoder module, usually used for the extraction
of embeddings from input signals.
pool: Pooling layer, used to reduce embeddings from the encoder.
head: Classification head, usually consists of Fully Connected layers.
"""
def __init__(
self, encoder: nn.Module, pool: nn.Module, head: nn.Module,
) -> None:
super().__init__()
self.encoder = encoder
self.pool = pool
self.head = head
def forward(self, x: torch.Tensor) -> torch.Tensor:
"""Forward call.
Args:
x: Batch of images.
Returns:
Batch of logits.
"""
x = self.pool(self.encoder(x))
x = x.view(x.shape[0], -1)
x = self.head(x)
return x
@classmethod
def get_from_params(
cls,
encoder_params: Optional[dict] = None,
pooling_params: Optional[dict] = None,
head_params: Optional[dict] = None,
) -> "VGGConv":
"""Create model based on it config.
Args:
encoder_params: Params of encoder module.
pooling_params: Params of the pooling layer.
head_params: 'Head' module params.
Returns:
Model.
"""
encoder: nn.Module = nn.Identity()
if (encoder_params_ := copy.deepcopy(encoder_params)) is not None:
encoder_fn = MODULE.get(encoder_params_.pop("module"))
encoder = encoder_fn(**encoder_params_)
pool: nn.Module = nn.Identity()
if (pooling_params_ := copy.deepcopy(pooling_params)) is not None:
pool_fn = MODULE.get(pooling_params_.pop("module"))
pool = pool_fn(**pooling_params_)
encoder_params: Params of encoder module.
pooling_params: Params of the pooling layer.
head_params: 'Head' module params.
Returns:
Model.
"""
encoder: nn.Module = nn.Identity()
if (encoder_params_ := copy.deepcopy(encoder_params)) is not None:
encoder_fn = MODULE.get(encoder_params_.pop("module"))
encoder = encoder_fn(**encoder_params_)
pool: nn.Module = nn.Identity()
if (pooling_params_ := copy.deepcopy(pooling_params)) is not None:
pool_fn = MODULE.get(pooling_params_.pop("module"))
pool = pool_fn(**pooling_params_)
head: nn.Module = nn.Identity()
if (head_params_ := copy.deepcopy(head_params)) is not None:
head_fn = MODULE.get(head_params_.pop("module"))
head = head_fn(**head_params_)
net = cls(encoder=encoder, pool=pool, head=head)
utils.net_init_(net)
return net
__all__ = ["VGGConv"]