diff options
Diffstat (limited to 'text_recognizer/networks')
| -rw-r--r-- | text_recognizer/networks/encoders/residual_network.py | 310 |
1 files changed, 0 insertions, 310 deletions
diff --git a/text_recognizer/networks/encoders/residual_network.py b/text_recognizer/networks/encoders/residual_network.py deleted file mode 100644 index c33f419..0000000 --- a/text_recognizer/networks/encoders/residual_network.py +++ /dev/null @@ -1,310 +0,0 @@ -"""Residual CNN.""" -from functools import partial -from typing import Callable, Dict, List, Optional, Type, Union - -from einops.layers.torch import Rearrange, Reduce -import torch -from torch import nn -from torch import Tensor - -from text_recognizer.networks.util import activation_function - - -class Conv2dAuto(nn.Conv2d): - """Convolution with auto padding based on kernel size.""" - - def __init__(self, *args, **kwargs) -> None: - super().__init__(*args, **kwargs) - self.padding = (self.kernel_size[0] // 2, self.kernel_size[1] // 2) - - -def conv_bn(in_channels: int, out_channels: int, *args, **kwargs) -> nn.Sequential: - """3x3 convolution with batch norm.""" - conv3x3 = partial(Conv2dAuto, kernel_size=3, bias=False,) - return nn.Sequential( - conv3x3(in_channels, out_channels, *args, **kwargs), - nn.BatchNorm2d(out_channels), - ) - - -class IdentityBlock(nn.Module): - """Residual with identity block.""" - - def __init__( - self, in_channels: int, out_channels: int, activation: str = "relu" - ) -> None: - super().__init__() - self.in_channels = in_channels - self.out_channels = out_channels - self.blocks = nn.Identity() - self.activation_fn = activation_function(activation) - self.shortcut = nn.Identity() - - def forward(self, x: Tensor) -> Tensor: - """Forward pass.""" - residual = x - if self.apply_shortcut: - residual = self.shortcut(x) - x = self.blocks(x) - x += residual - x = self.activation_fn(x) - return x - - @property - def apply_shortcut(self) -> bool: - """Check if shortcut should be applied.""" - return self.in_channels != self.out_channels - - -class ResidualBlock(IdentityBlock): - """Residual with nonlinear shortcut.""" - - def __init__( - self, - in_channels: int, - out_channels: int, - expansion: int = 1, - downsampling: int = 1, - *args, - **kwargs - ) -> None: - """Short summary. - - Args: - in_channels (int): Number of in channels. - out_channels (int): umber of out channels. - expansion (int): Expansion factor of the out channels. Defaults to 1. - downsampling (int): Downsampling factor used in stride. Defaults to 1. - *args (type): Extra arguments. - **kwargs (type): Extra key value arguments. - - """ - super().__init__(in_channels, out_channels, *args, **kwargs) - self.expansion = expansion - self.downsampling = downsampling - - self.shortcut = ( - nn.Sequential( - nn.Conv2d( - in_channels=self.in_channels, - out_channels=self.expanded_channels, - kernel_size=1, - stride=self.downsampling, - bias=False, - ), - nn.BatchNorm2d(self.expanded_channels), - ) - if self.apply_shortcut - else None - ) - - @property - def expanded_channels(self) -> int: - """Computes the expanded output channels.""" - return self.out_channels * self.expansion - - @property - def apply_shortcut(self) -> bool: - """Check if shortcut should be applied.""" - return self.in_channels != self.expanded_channels - - -class BasicBlock(ResidualBlock): - """Basic ResNet block.""" - - expansion = 1 - - def __init__(self, in_channels: int, out_channels: int, *args, **kwargs) -> None: - super().__init__(in_channels, out_channels, *args, **kwargs) - self.blocks = nn.Sequential( - conv_bn( - in_channels=self.in_channels, - out_channels=self.out_channels, - bias=False, - stride=self.downsampling, - ), - self.activation_fn, - conv_bn( - in_channels=self.out_channels, - out_channels=self.expanded_channels, - bias=False, - ), - ) - - -class BottleNeckBlock(ResidualBlock): - """Bottleneck block to increase depth while minimizing parameter size.""" - - expansion = 4 - - def __init__(self, in_channels: int, out_channels: int, *args, **kwargs) -> None: - super().__init__(in_channels, out_channels, *args, **kwargs) - self.blocks = nn.Sequential( - conv_bn( - in_channels=self.in_channels, - out_channels=self.out_channels, - kernel_size=1, - ), - self.activation_fn, - conv_bn( - in_channels=self.out_channels, - out_channels=self.out_channels, - kernel_size=3, - stride=self.downsampling, - ), - self.activation_fn, - conv_bn( - in_channels=self.out_channels, - out_channels=self.expanded_channels, - kernel_size=1, - ), - ) - - -class ResidualLayer(nn.Module): - """ResNet layer.""" - - def __init__( - self, - in_channels: int, - out_channels: int, - block: BasicBlock = BasicBlock, - num_blocks: int = 1, - *args, - **kwargs - ) -> None: - super().__init__() - downsampling = 2 if in_channels != out_channels else 1 - self.blocks = nn.Sequential( - block( - in_channels, out_channels, *args, **kwargs, downsampling=downsampling - ), - *[ - block( - out_channels * block.expansion, - out_channels, - downsampling=1, - *args, - **kwargs - ) - for _ in range(num_blocks - 1) - ] - ) - - def forward(self, x: Tensor) -> Tensor: - """Forward pass.""" - x = self.blocks(x) - return x - - -class ResidualNetworkEncoder(nn.Module): - """Encoder network.""" - - def __init__( - self, - in_channels: int = 1, - block_sizes: Union[int, List[int]] = (32, 64), - depths: Union[int, List[int]] = (2, 2), - activation: str = "relu", - block: Type[nn.Module] = BasicBlock, - levels: int = 1, - *args, - **kwargs - ) -> None: - super().__init__() - self.block_sizes = ( - block_sizes if isinstance(block_sizes, list) else [block_sizes] * levels - ) - self.depths = depths if isinstance(depths, list) else [depths] * levels - self.activation = activation - self.gate = nn.Sequential( - nn.Conv2d( - in_channels=in_channels, - out_channels=self.block_sizes[0], - kernel_size=7, - stride=2, - padding=1, - bias=False, - ), - nn.BatchNorm2d(self.block_sizes[0]), - activation_function(self.activation), - # nn.MaxPool2d(kernel_size=2, stride=2, padding=1), - ) - - self.blocks = self._configure_blocks(block) - - def _configure_blocks( - self, block: Type[nn.Module], *args, **kwargs - ) -> nn.Sequential: - channels = [self.block_sizes[0]] + list( - zip(self.block_sizes, self.block_sizes[1:]) - ) - blocks = [ - ResidualLayer( - in_channels=channels[0], - out_channels=channels[0], - num_blocks=self.depths[0], - block=block, - activation=self.activation, - *args, - **kwargs - ) - ] - blocks += [ - ResidualLayer( - in_channels=in_channels * block.expansion, - out_channels=out_channels, - num_blocks=num_blocks, - block=block, - activation=self.activation, - *args, - **kwargs - ) - for (in_channels, out_channels), num_blocks in zip( - channels[1:], self.depths[1:] - ) - ] - - return nn.Sequential(*blocks) - - def forward(self, x: Tensor) -> Tensor: - """Forward pass.""" - # If batch dimenstion is missing, it needs to be added. - if len(x.shape) == 3: - x = x.unsqueeze(0) - x = self.gate(x) - x = self.blocks(x) - return x - - -class ResidualNetworkDecoder(nn.Module): - """Classification head.""" - - def __init__(self, in_features: int, num_classes: int = 80) -> None: - super().__init__() - self.decoder = nn.Sequential( - Reduce("b c h w -> b c", "mean"), - nn.Linear(in_features=in_features, out_features=num_classes), - ) - - def forward(self, x: Tensor) -> Tensor: - """Forward pass.""" - return self.decoder(x) - - -class ResidualNetwork(nn.Module): - """Full residual network.""" - - def __init__(self, in_channels: int, num_classes: int, *args, **kwargs) -> None: - super().__init__() - self.encoder = ResidualNetworkEncoder(in_channels, *args, **kwargs) - self.decoder = ResidualNetworkDecoder( - in_features=self.encoder.blocks[-1].blocks[-1].expanded_channels, - num_classes=num_classes, - ) - - def forward(self, x: Tensor) -> Tensor: - """Forward pass.""" - x = self.encoder(x) - x = self.decoder(x) - return x |