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-rw-r--r--text_recognizer/networks/__init__.py43
-rw-r--r--text_recognizer/networks/beam.py83
-rw-r--r--text_recognizer/networks/cnn.py101
-rw-r--r--text_recognizer/networks/crnn.py110
-rw-r--r--text_recognizer/networks/ctc.py58
-rw-r--r--text_recognizer/networks/densenet.py225
-rw-r--r--text_recognizer/networks/lenet.py68
-rw-r--r--text_recognizer/networks/metrics.py123
-rw-r--r--text_recognizer/networks/mlp.py73
-rw-r--r--text_recognizer/networks/stn.py44
-rw-r--r--text_recognizer/networks/unet.py255
-rw-r--r--text_recognizer/networks/vit.py150
12 files changed, 0 insertions, 1333 deletions
diff --git a/text_recognizer/networks/__init__.py b/text_recognizer/networks/__init__.py
index 1521355..e69de29 100644
--- a/text_recognizer/networks/__init__.py
+++ b/text_recognizer/networks/__init__.py
@@ -1,43 +0,0 @@
-"""Network modules."""
-from .cnn import CNN
-from .cnn_transformer import CNNTransformer
-from .crnn import ConvolutionalRecurrentNetwork
-from .ctc import greedy_decoder
-from .densenet import DenseNet
-from .lenet import LeNet
-from .metrics import accuracy, cer, wer
-from .mlp import MLP
-from .residual_network import ResidualNetwork, ResidualNetworkEncoder
-from .transducer import load_transducer_loss, TDS2d
-from .transformer import Transformer
-from .unet import UNet
-from .util import sliding_window
-from .vit import ViT
-from .vq_transformer import VQTransformer
-from .vqvae import VQVAE
-from .wide_resnet import WideResidualNetwork
-
-__all__ = [
- "accuracy",
- "cer",
- "CNN",
- "CNNTransformer",
- "ConvolutionalRecurrentNetwork",
- "DenseNet",
- "FCN",
- "greedy_decoder",
- "MLP",
- "LeNet",
- "load_transducer_loss",
- "ResidualNetwork",
- "ResidualNetworkEncoder",
- "sliding_window",
- "UNet",
- "TDS2d",
- "Transformer",
- "ViT",
- "VQTransformer",
- "VQVAE",
- "wer",
- "WideResidualNetwork",
-]
diff --git a/text_recognizer/networks/beam.py b/text_recognizer/networks/beam.py
deleted file mode 100644
index dccccdb..0000000
--- a/text_recognizer/networks/beam.py
+++ /dev/null
@@ -1,83 +0,0 @@
-"""Implementation of beam search decoder for a sequence to sequence network.
-
-Stolen from: https://github.com/budzianowski/PyTorch-Beam-Search-Decoding/blob/master/decode_beam.py
-
-"""
-# from typing import List
-# from Queue import PriorityQueue
-
-# from loguru import logger
-# import torch
-# from torch import nn
-# from torch import Tensor
-# import torch.nn.functional as F
-
-
-# class Node:
-# def __init__(
-# self, parent: Node, target_index: int, log_prob: Tensor, length: int
-# ) -> None:
-# self.parent = parent
-# self.target_index = target_index
-# self.log_prob = log_prob
-# self.length = length
-# self.reward = 0.0
-
-# def eval(self, alpha: float = 1.0) -> Tensor:
-# return self.log_prob / (self.length - 1 + 1e-6) + alpha * self.reward
-
-
-# @torch.no_grad()
-# def beam_decoder(
-# network, mapper, device, memory: Tensor = None, max_len: int = 97,
-# ) -> Tensor:
-# beam_width = 10
-# topk = 1 # How many sentences to generate.
-
-# trg_indices = [mapper(mapper.init_token)]
-
-# end_nodes = []
-
-# node = Node(None, trg_indices, 0, 1)
-# nodes = PriorityQueue()
-
-# nodes.put((node.eval(), node))
-# q_size = 1
-
-# # Beam search
-# for _ in range(max_len):
-# if q_size > 2000:
-# logger.warning("Could not decoder input")
-# break
-
-# # Fetch the best node.
-# score, n = nodes.get()
-# decoder_input = n.target_index
-
-# if n.target_index == mapper(mapper.eos_token) and n.parent is not None:
-# end_nodes.append((score, n))
-
-# # If we reached the maximum number of sentences required.
-# if len(end_nodes) >= 1:
-# break
-# else:
-# continue
-
-# # Forward pass with transformer.
-# trg = torch.tensor(trg_indices, device=device)[None, :].long()
-# trg = network.target_embedding(trg)
-# logits = network.decoder(trg=trg, memory=memory, trg_mask=None)
-# log_prob = F.log_softmax(logits, dim=2)
-
-# log_prob, indices = torch.topk(log_prob, beam_width)
-
-# for new_k in range(beam_width):
-# # TODO: continue from here
-# token_index = indices[0][new_k].view(1, -1)
-# log_p = log_prob[0][new_k].item()
-
-# node = Node()
-
-# pass
-
-# pass
diff --git a/text_recognizer/networks/cnn.py b/text_recognizer/networks/cnn.py
deleted file mode 100644
index 1807bb9..0000000
--- a/text_recognizer/networks/cnn.py
+++ /dev/null
@@ -1,101 +0,0 @@
-"""Implementation of a simple backbone cnn network."""
-from typing import Callable, Dict, Optional, Tuple
-
-from einops.layers.torch import Rearrange
-import torch
-from torch import nn
-
-from text_recognizer.networks.util import activation_function
-
-
-class CNN(nn.Module):
- """LeNet network for character prediction."""
-
- def __init__(
- self,
- channels: Tuple[int, ...] = (1, 32, 64, 128),
- kernel_sizes: Tuple[int, ...] = (4, 4, 4),
- strides: Tuple[int, ...] = (2, 2, 2),
- max_pool_kernel: int = 2,
- dropout_rate: float = 0.2,
- activation: Optional[str] = "relu",
- ) -> None:
- """Initialization of the LeNet network.
-
- Args:
- channels (Tuple[int, ...]): Channels in the convolutional layers. Defaults to (1, 32, 64).
- kernel_sizes (Tuple[int, ...]): Kernel sizes in the convolutional layers. Defaults to (3, 3, 2).
- strides (Tuple[int, ...]): Stride length of the convolutional filter. Defaults to (2, 2, 2).
- max_pool_kernel (int): 2D max pooling kernel. Defaults to 2.
- dropout_rate (float): The dropout rate. Defaults to 0.2.
- activation (Optional[str]): The name of non-linear activation function. Defaults to relu.
-
- Raises:
- RuntimeError: if the number of hyperparameters does not match in length.
-
- """
- super().__init__()
-
- if len(channels) - 1 != len(kernel_sizes) and len(kernel_sizes) != len(strides):
- raise RuntimeError("The number of the hyperparameters does not match.")
-
- self.cnn = self._build_network(
- channels, kernel_sizes, strides, max_pool_kernel, dropout_rate, activation,
- )
-
- def _build_network(
- self,
- channels: Tuple[int, ...],
- kernel_sizes: Tuple[int, ...],
- strides: Tuple[int, ...],
- max_pool_kernel: int,
- dropout_rate: float,
- activation: str,
- ) -> nn.Sequential:
- # Load activation function.
- activation_fn = activation_function(activation)
-
- channels = list(channels)
- in_channels = channels.pop(0)
- configuration = zip(channels, kernel_sizes, strides)
-
- modules = nn.ModuleList([])
-
- for i, (out_channels, kernel_size, stride) in enumerate(configuration):
- # Add max pool to reduce output size.
- if i == len(channels) // 2:
- modules.append(nn.MaxPool2d(max_pool_kernel))
- if i == 0:
- modules.append(
- nn.Conv2d(
- in_channels, out_channels, kernel_size, stride=stride, padding=1
- )
- )
- else:
- modules.append(
- nn.Sequential(
- activation_fn,
- nn.BatchNorm2d(in_channels),
- nn.Conv2d(
- in_channels,
- out_channels,
- kernel_size,
- stride=stride,
- padding=1,
- ),
- )
- )
-
- if dropout_rate:
- modules.append(nn.Dropout2d(p=dropout_rate))
-
- in_channels = out_channels
-
- return nn.Sequential(*modules)
-
- def forward(self, x: torch.Tensor) -> torch.Tensor:
- """The feedforward pass."""
- # If batch dimenstion is missing, it needs to be added.
- if len(x.shape) < 4:
- x = x[(None,) * (4 - len(x.shape))]
- return self.cnn(x)
diff --git a/text_recognizer/networks/crnn.py b/text_recognizer/networks/crnn.py
deleted file mode 100644
index 778e232..0000000
--- a/text_recognizer/networks/crnn.py
+++ /dev/null
@@ -1,110 +0,0 @@
-"""CRNN for handwritten text recognition."""
-from typing import Dict, Tuple
-
-from einops import rearrange, reduce
-from einops.layers.torch import Rearrange
-from loguru import logger
-from torch import nn
-from torch import Tensor
-
-from text_recognizer.networks.util import configure_backbone
-
-
-class ConvolutionalRecurrentNetwork(nn.Module):
- """Network that takes a image of a text line and predicts tokens that are in the image."""
-
- def __init__(
- self,
- backbone: str,
- backbone_args: Dict = None,
- input_size: int = 128,
- hidden_size: int = 128,
- bidirectional: bool = False,
- num_layers: int = 1,
- num_classes: int = 80,
- patch_size: Tuple[int, int] = (28, 28),
- stride: Tuple[int, int] = (1, 14),
- recurrent_cell: str = "lstm",
- avg_pool: bool = False,
- use_sliding_window: bool = True,
- ) -> None:
- super().__init__()
- self.backbone_args = backbone_args or {}
- self.patch_size = patch_size
- self.stride = stride
- self.sliding_window = (
- self._configure_sliding_window() if use_sliding_window else None
- )
- self.input_size = input_size
- self.hidden_size = hidden_size
- self.backbone = configure_backbone(backbone, backbone_args)
- self.bidirectional = bidirectional
- self.avg_pool = avg_pool
-
- if recurrent_cell.upper() in ["LSTM", "GRU"]:
- recurrent_cell = getattr(nn, recurrent_cell)
- else:
- logger.warning(
- f"Option {recurrent_cell} not valid, defaulting to LSTM cell."
- )
- recurrent_cell = nn.LSTM
-
- self.rnn = recurrent_cell(
- input_size=self.input_size,
- hidden_size=self.hidden_size,
- bidirectional=bidirectional,
- num_layers=num_layers,
- )
-
- decoder_size = self.hidden_size * 2 if self.bidirectional else self.hidden_size
-
- self.decoder = nn.Sequential(
- nn.Linear(in_features=decoder_size, out_features=num_classes),
- nn.LogSoftmax(dim=2),
- )
-
- def _configure_sliding_window(self) -> nn.Sequential:
- return nn.Sequential(
- nn.Unfold(kernel_size=self.patch_size, stride=self.stride),
- Rearrange(
- "b (c h w) t -> b t c h w",
- h=self.patch_size[0],
- w=self.patch_size[1],
- c=1,
- ),
- )
-
- def forward(self, x: Tensor) -> Tensor:
- """Converts images to sequence of patches, feeds them to a CNN, then predictions are made with an LSTM."""
- if len(x.shape) < 4:
- x = x[(None,) * (4 - len(x.shape))]
-
- if self.sliding_window is not None:
- # Create image patches with a sliding window kernel.
- x = self.sliding_window(x)
-
- # Rearrange from a sequence of patches for feedforward network.
- b, t = x.shape[:2]
- x = rearrange(x, "b t c h w -> (b t) c h w", b=b, t=t)
-
- x = self.backbone(x)
-
- # Average pooling.
- if self.avg_pool:
- x = reduce(x, "(b t) c h w -> t b c", "mean", b=b, t=t)
- else:
- x = rearrange(x, "(b t) h -> t b h", b=b, t=t)
- else:
- # Encode the entire image with a CNN, and use the channels as temporal dimension.
- x = self.backbone(x)
- x = rearrange(x, "b c h w -> b w c h")
- if self.adaptive_pool is not None:
- x = self.adaptive_pool(x)
- x = x.squeeze(3)
-
- # Sequence predictions.
- x, _ = self.rnn(x)
-
- # Sequence to classification layer.
- x = self.decoder(x)
- return x
diff --git a/text_recognizer/networks/ctc.py b/text_recognizer/networks/ctc.py
deleted file mode 100644
index af9b700..0000000
--- a/text_recognizer/networks/ctc.py
+++ /dev/null
@@ -1,58 +0,0 @@
-"""Decodes the CTC output."""
-from typing import Callable, List, Optional, Tuple
-
-from einops import rearrange
-import torch
-from torch import Tensor
-
-from text_recognizer.datasets.util import EmnistMapper
-
-
-def greedy_decoder(
- predictions: Tensor,
- targets: Optional[Tensor] = None,
- target_lengths: Optional[Tensor] = None,
- character_mapper: Optional[Callable] = None,
- blank_label: int = 79,
- collapse_repeated: bool = True,
-) -> Tuple[List[str], List[str]]:
- """Greedy CTC decoder.
-
- Args:
- predictions (Tensor): Tenor of network predictions, shape [time, batch, classes].
- targets (Optional[Tensor]): Target tensor, shape is [batch, targets]. Defaults to None.
- target_lengths (Optional[Tensor]): Length of each target tensor. Defaults to None.
- character_mapper (Optional[Callable]): A emnist/character mapper for mapping integers to characters. Defaults
- to None.
- blank_label (int): The blank character to be ignored. Defaults to 80.
- collapse_repeated (bool): Collapase consecutive predictions of the same character. Defaults to True.
-
- Returns:
- Tuple[List[str], List[str]]: Tuple of decoded predictions and decoded targets.
-
- """
-
- if character_mapper is None:
- character_mapper = EmnistMapper(pad_token="_") # noqa: S106
-
- predictions = rearrange(torch.argmax(predictions, dim=2), "t b -> b t")
- decoded_predictions = []
- decoded_targets = []
- for i, prediction in enumerate(predictions):
- decoded_prediction = []
- decoded_target = []
- if targets is not None and target_lengths is not None:
- for target_index in targets[i][: target_lengths[i]]:
- if target_index == blank_label:
- continue
- decoded_target.append(character_mapper(int(target_index)))
- decoded_targets.append(decoded_target)
- for j, index in enumerate(prediction):
- if index != blank_label:
- if collapse_repeated and j != 0 and index == prediction[j - 1]:
- continue
- decoded_prediction.append(index.item())
- decoded_predictions.append(
- [character_mapper(int(pred_index)) for pred_index in decoded_prediction]
- )
- return decoded_predictions, decoded_targets
diff --git a/text_recognizer/networks/densenet.py b/text_recognizer/networks/densenet.py
deleted file mode 100644
index 7dc58d9..0000000
--- a/text_recognizer/networks/densenet.py
+++ /dev/null
@@ -1,225 +0,0 @@
-"""Defines a Densely Connected Convolutional Networks in PyTorch.
-
-Sources:
-https://arxiv.org/abs/1608.06993
-https://github.com/pytorch/vision/blob/master/torchvision/models/densenet.py
-
-"""
-from typing import List, Optional, Union
-
-from einops.layers.torch import Rearrange
-import torch
-from torch import nn
-from torch import Tensor
-
-from text_recognizer.networks.util import activation_function
-
-
-class _DenseLayer(nn.Module):
- """A dense layer with pre-batch norm -> activation function -> Conv-layer x 2."""
-
- def __init__(
- self,
- in_channels: int,
- growth_rate: int,
- bn_size: int,
- dropout_rate: float,
- activation: str = "relu",
- ) -> None:
- super().__init__()
- activation_fn = activation_function(activation)
- self.dense_layer = [
- nn.BatchNorm2d(in_channels),
- activation_fn,
- nn.Conv2d(
- in_channels=in_channels,
- out_channels=bn_size * growth_rate,
- kernel_size=1,
- stride=1,
- bias=False,
- ),
- nn.BatchNorm2d(bn_size * growth_rate),
- activation_fn,
- nn.Conv2d(
- in_channels=bn_size * growth_rate,
- out_channels=growth_rate,
- kernel_size=3,
- stride=1,
- padding=1,
- bias=False,
- ),
- ]
- if dropout_rate:
- self.dense_layer.append(nn.Dropout(p=dropout_rate))
-
- self.dense_layer = nn.Sequential(*self.dense_layer)
-
- def forward(self, x: Union[Tensor, List[Tensor]]) -> Tensor:
- if isinstance(x, list):
- x = torch.cat(x, 1)
- return self.dense_layer(x)
-
-
-class _DenseBlock(nn.Module):
- def __init__(
- self,
- num_layers: int,
- in_channels: int,
- bn_size: int,
- growth_rate: int,
- dropout_rate: float,
- activation: str = "relu",
- ) -> None:
- super().__init__()
- self.dense_block = self._build_dense_blocks(
- num_layers, in_channels, bn_size, growth_rate, dropout_rate, activation,
- )
-
- def _build_dense_blocks(
- self,
- num_layers: int,
- in_channels: int,
- bn_size: int,
- growth_rate: int,
- dropout_rate: float,
- activation: str = "relu",
- ) -> nn.ModuleList:
- dense_block = []
- for i in range(num_layers):
- dense_block.append(
- _DenseLayer(
- in_channels=in_channels + i * growth_rate,
- growth_rate=growth_rate,
- bn_size=bn_size,
- dropout_rate=dropout_rate,
- activation=activation,
- )
- )
- return nn.ModuleList(dense_block)
-
- def forward(self, x: Tensor) -> Tensor:
- feature_maps = [x]
- for layer in self.dense_block:
- x = layer(feature_maps)
- feature_maps.append(x)
- return torch.cat(feature_maps, 1)
-
-
-class _Transition(nn.Module):
- def __init__(
- self, in_channels: int, out_channels: int, activation: str = "relu",
- ) -> None:
- super().__init__()
- activation_fn = activation_function(activation)
- self.transition = nn.Sequential(
- nn.BatchNorm2d(in_channels),
- activation_fn,
- nn.Conv2d(
- in_channels=in_channels,
- out_channels=out_channels,
- kernel_size=1,
- stride=1,
- bias=False,
- ),
- nn.AvgPool2d(kernel_size=2, stride=2),
- )
-
- def forward(self, x: Tensor) -> Tensor:
- return self.transition(x)
-
-
-class DenseNet(nn.Module):
- """Implementation of Densenet, a network archtecture that concats previous layers for maximum infomation flow."""
-
- def __init__(
- self,
- growth_rate: int = 32,
- block_config: List[int] = (6, 12, 24, 16),
- in_channels: int = 1,
- base_channels: int = 64,
- num_classes: int = 80,
- bn_size: int = 4,
- dropout_rate: float = 0,
- classifier: bool = True,
- activation: str = "relu",
- ) -> None:
- super().__init__()
- self.densenet = self._configure_densenet(
- in_channels,
- base_channels,
- num_classes,
- growth_rate,
- block_config,
- bn_size,
- dropout_rate,
- classifier,
- activation,
- )
-
- def _configure_densenet(
- self,
- in_channels: int,
- base_channels: int,
- num_classes: int,
- growth_rate: int,
- block_config: List[int],
- bn_size: int,
- dropout_rate: float,
- classifier: bool,
- activation: str,
- ) -> nn.Sequential:
- activation_fn = activation_function(activation)
- densenet = [
- nn.Conv2d(
- in_channels=in_channels,
- out_channels=base_channels,
- kernel_size=3,
- stride=1,
- padding=1,
- bias=False,
- ),
- nn.BatchNorm2d(base_channels),
- activation_fn,
- ]
-
- num_features = base_channels
-
- for i, num_layers in enumerate(block_config):
- densenet.append(
- _DenseBlock(
- num_layers=num_layers,
- in_channels=num_features,
- bn_size=bn_size,
- growth_rate=growth_rate,
- dropout_rate=dropout_rate,
- activation=activation,
- )
- )
- num_features = num_features + num_layers * growth_rate
- if i != len(block_config) - 1:
- densenet.append(
- _Transition(
- in_channels=num_features,
- out_channels=num_features // 2,
- activation=activation,
- )
- )
- num_features = num_features // 2
-
- densenet.append(activation_fn)
-
- if classifier:
- densenet.append(nn.AdaptiveAvgPool2d((1, 1)))
- densenet.append(Rearrange("b c h w -> b (c h w)"))
- densenet.append(
- nn.Linear(in_features=num_features, out_features=num_classes)
- )
-
- return nn.Sequential(*densenet)
-
- def forward(self, x: Tensor) -> Tensor:
- """Forward pass of Densenet."""
- # If batch dimenstion is missing, it will be added.
- if len(x.shape) < 4:
- x = x[(None,) * (4 - len(x.shape))]
- return self.densenet(x)
diff --git a/text_recognizer/networks/lenet.py b/text_recognizer/networks/lenet.py
deleted file mode 100644
index 527e1a0..0000000
--- a/text_recognizer/networks/lenet.py
+++ /dev/null
@@ -1,68 +0,0 @@
-"""Implementation of the LeNet network."""
-from typing import Callable, Dict, Optional, Tuple
-
-from einops.layers.torch import Rearrange
-import torch
-from torch import nn
-
-from text_recognizer.networks.util import activation_function
-
-
-class LeNet(nn.Module):
- """LeNet network for character prediction."""
-
- def __init__(
- self,
- channels: Tuple[int, ...] = (1, 32, 64),
- kernel_sizes: Tuple[int, ...] = (3, 3, 2),
- hidden_size: Tuple[int, ...] = (9216, 128),
- dropout_rate: float = 0.2,
- num_classes: int = 10,
- activation_fn: Optional[str] = "relu",
- ) -> None:
- """Initialization of the LeNet network.
-
- Args:
- channels (Tuple[int, ...]): Channels in the convolutional layers. Defaults to (1, 32, 64).
- kernel_sizes (Tuple[int, ...]): Kernel sizes in the convolutional layers. Defaults to (3, 3, 2).
- hidden_size (Tuple[int, ...]): Size of the flattend output form the convolutional layers.
- Defaults to (9216, 128).
- dropout_rate (float): The dropout rate. Defaults to 0.2.
- num_classes (int): Number of classes. Defaults to 10.
- activation_fn (Optional[str]): The name of non-linear activation function. Defaults to relu.
-
- """
- super().__init__()
-
- activation_fn = activation_function(activation_fn)
-
- self.layers = [
- nn.Conv2d(
- in_channels=channels[0],
- out_channels=channels[1],
- kernel_size=kernel_sizes[0],
- ),
- activation_fn,
- nn.Conv2d(
- in_channels=channels[1],
- out_channels=channels[2],
- kernel_size=kernel_sizes[1],
- ),
- activation_fn,
- nn.MaxPool2d(kernel_sizes[2]),
- nn.Dropout(p=dropout_rate),
- Rearrange("b c h w -> b (c h w)"),
- nn.Linear(in_features=hidden_size[0], out_features=hidden_size[1]),
- activation_fn,
- nn.Dropout(p=dropout_rate),
- nn.Linear(in_features=hidden_size[1], out_features=num_classes),
- ]
-
- self.layers = nn.Sequential(*self.layers)
-
- def forward(self, x: torch.Tensor) -> torch.Tensor:
- """The feedforward pass."""
- # If batch dimenstion is missing, it needs to be added.
- if len(x.shape) < 4:
- x = x[(None,) * (4 - len(x.shape))]
- return self.layers(x)
diff --git a/text_recognizer/networks/metrics.py b/text_recognizer/networks/metrics.py
deleted file mode 100644
index 2605731..0000000
--- a/text_recognizer/networks/metrics.py
+++ /dev/null
@@ -1,123 +0,0 @@
-"""Utility functions for models."""
-from typing import Optional
-
-from einops import rearrange
-import Levenshtein as Lev
-import torch
-from torch import Tensor
-
-from text_recognizer.networks import greedy_decoder
-
-
-def accuracy(outputs: Tensor, labels: Tensor, pad_index: int = 53) -> float:
- """Computes the accuracy.
-
- Args:
- outputs (Tensor): The output from the network.
- labels (Tensor): Ground truth labels.
- pad_index (int): Padding index.
-
- Returns:
- float: The accuracy for the batch.
-
- """
-
- _, predicted = torch.max(outputs, dim=-1)
-
- # Mask out the pad tokens
- mask = labels != pad_index
-
- predicted *= mask
- labels *= mask
-
- acc = (predicted == labels).sum().float() / labels.shape[0]
- acc = acc.item()
- return acc
-
-
-def cer(
- outputs: Tensor,
- targets: Tensor,
- batch_size: Optional[int] = None,
- blank_label: Optional[int] = int,
-) -> float:
- """Computes the character error rate.
-
- Args:
- outputs (Tensor): The output from the network.
- targets (Tensor): Ground truth labels.
- batch_size (Optional[int]): Batch size if target and output has been flattend.
- blank_label (Optional[int]): The blank character to be ignored. Defaults to 79.
-
- Returns:
- float: The cer for the batch.
-
- """
- if len(outputs.shape) == 2 and len(targets.shape) == 1 and batch_size is not None:
- targets = rearrange(targets, "(b t) -> b t", b=batch_size)
- outputs = rearrange(outputs, "(b t) v -> t b v", b=batch_size)
-
- target_lengths = torch.full(
- size=(outputs.shape[1],), fill_value=targets.shape[1], dtype=torch.long,
- )
- decoded_predictions, decoded_targets = greedy_decoder(
- outputs, targets, target_lengths, blank_label=blank_label,
- )
-
- lev_dist = 0
-
- for prediction, target in zip(decoded_predictions, decoded_targets):
- prediction = "".join(prediction)
- target = "".join(target)
- prediction, target = (
- prediction.replace(" ", ""),
- target.replace(" ", ""),
- )
- lev_dist += Lev.distance(prediction, target)
- return lev_dist / len(decoded_predictions)
-
-
-def wer(
- outputs: Tensor,
- targets: Tensor,
- batch_size: Optional[int] = None,
- blank_label: Optional[int] = int,
-) -> float:
- """Computes the Word error rate.
-
- Args:
- outputs (Tensor): The output from the network.
- targets (Tensor): Ground truth labels.
- batch_size (optional[int]): Batch size if target and output has been flattend.
- blank_label (Optional[int]): The blank character to be ignored. Defaults to 79.
-
- Returns:
- float: The wer for the batch.
-
- """
- if len(outputs.shape) == 2 and len(targets.shape) == 1 and batch_size is not None:
- targets = rearrange(targets, "(b t) -> b t", b=batch_size)
- outputs = rearrange(outputs, "(b t) v -> t b v", b=batch_size)
-
- target_lengths = torch.full(
- size=(outputs.shape[1],), fill_value=targets.shape[1], dtype=torch.long,
- )
- decoded_predictions, decoded_targets = greedy_decoder(
- outputs, targets, target_lengths, blank_label=blank_label,
- )
-
- lev_dist = 0
-
- for prediction, target in zip(decoded_predictions, decoded_targets):
- prediction = "".join(prediction)
- target = "".join(target)
-
- b = set(prediction.split() + target.split())
- word2char = dict(zip(b, range(len(b))))
-
- w1 = [chr(word2char[w]) for w in prediction.split()]
- w2 = [chr(word2char[w]) for w in target.split()]
-
- lev_dist += Lev.distance("".join(w1), "".join(w2))
-
- return lev_dist / len(decoded_predictions)
diff --git a/text_recognizer/networks/mlp.py b/text_recognizer/networks/mlp.py
deleted file mode 100644
index 1101912..0000000
--- a/text_recognizer/networks/mlp.py
+++ /dev/null
@@ -1,73 +0,0 @@
-"""Defines the MLP network."""
-from typing import Callable, Dict, List, Optional, Union
-
-from einops.layers.torch import Rearrange
-import torch
-from torch import nn
-
-from text_recognizer.networks.util import activation_function
-
-
-class MLP(nn.Module):
- """Multi layered perceptron network."""
-
- def __init__(
- self,
- input_size: int = 784,
- num_classes: int = 10,
- hidden_size: Union[int, List] = 128,
- num_layers: int = 3,
- dropout_rate: float = 0.2,
- activation_fn: str = "relu",
- ) -> None:
- """Initialization of the MLP network.
-
- Args:
- input_size (int): The input shape of the network. Defaults to 784.
- num_classes (int): Number of classes in the dataset. Defaults to 10.
- hidden_size (Union[int, List]): The number of `neurons` in each hidden layer. Defaults to 128.
- num_layers (int): The number of hidden layers. Defaults to 3.
- dropout_rate (float): The dropout rate at each layer. Defaults to 0.2.
- activation_fn (str): Name of the activation function in the hidden layers. Defaults to
- relu.
-
- """
- super().__init__()
-
- activation_fn = activation_function(activation_fn)
-
- if isinstance(hidden_size, int):
- hidden_size = [hidden_size] * num_layers
-
- self.layers = [
- Rearrange("b c h w -> b (c h w)"),
- nn.Linear(in_features=input_size, out_features=hidden_size[0]),
- activation_fn,
- ]
-
- for i in range(num_layers - 1):
- self.layers += [
- nn.Linear(in_features=hidden_size[i], out_features=hidden_size[i + 1]),
- activation_fn,
- ]
-
- if dropout_rate:
- self.layers.append(nn.Dropout(p=dropout_rate))
-
- self.layers.append(
- nn.Linear(in_features=hidden_size[-1], out_features=num_classes)
- )
-
- self.layers = nn.Sequential(*self.layers)
-
- def forward(self, x: torch.Tensor) -> torch.Tensor:
- """The feedforward pass."""
- # If batch dimenstion is missing, it needs to be added.
- if len(x.shape) < 4:
- x = x[(None,) * (4 - len(x.shape))]
- return self.layers(x)
-
- @property
- def __name__(self) -> str:
- """Returns the name of the network."""
- return "mlp"
diff --git a/text_recognizer/networks/stn.py b/text_recognizer/networks/stn.py
deleted file mode 100644
index e9d216f..0000000
--- a/text_recognizer/networks/stn.py
+++ /dev/null
@@ -1,44 +0,0 @@
-"""Spatial Transformer Network."""
-
-from einops.layers.torch import Rearrange
-import torch
-from torch import nn
-from torch import Tensor
-import torch.nn.functional as F
-
-
-class SpatialTransformerNetwork(nn.Module):
- """A network with differentiable attention.
-
- Network that learns how to perform spatial transformations on the input image in order to enhance the
- geometric invariance of the model.
-
- # TODO: add arguments to make it more general.
-
- """
-
- def __init__(self) -> None:
- super().__init__()
- # Initialize the identity transformation and its weights and biases.
- linear = nn.Linear(32, 3 * 2)
- linear.weight.data.zero_()
- linear.bias.data.copy_(torch.tensor([1, 0, 0, 0, 1, 0], dtype=torch.float))
-
- self.theta = nn.Sequential(
- nn.Conv2d(in_channels=1, out_channels=8, kernel_size=7),
- nn.MaxPool2d(kernel_size=2, stride=2),
- nn.ReLU(inplace=True),
- nn.Conv2d(in_channels=8, out_channels=10, kernel_size=5),
- nn.MaxPool2d(kernel_size=2, stride=2),
- nn.ReLU(inplace=True),
- Rearrange("b c h w -> b (c h w)", h=3, w=3),
- nn.Linear(in_features=10 * 3 * 3, out_features=32),
- nn.ReLU(inplace=True),
- linear,
- Rearrange("b (row col) -> b row col", row=2, col=3),
- )
-
- def forward(self, x: Tensor) -> Tensor:
- """The spatial transformation."""
- grid = F.affine_grid(self.theta(x), x.shape)
- return F.grid_sample(x, grid, align_corners=False)
diff --git a/text_recognizer/networks/unet.py b/text_recognizer/networks/unet.py
deleted file mode 100644
index 510910f..0000000
--- a/text_recognizer/networks/unet.py
+++ /dev/null
@@ -1,255 +0,0 @@
-"""UNet for segmentation."""
-from typing import List, Optional, Tuple, Union
-
-import torch
-from torch import nn
-from torch import Tensor
-
-from text_recognizer.networks.util import activation_function
-
-
-class _ConvBlock(nn.Module):
- """Modified UNet convolutional block with dilation."""
-
- def __init__(
- self,
- channels: List[int],
- activation: str,
- num_groups: int,
- dropout_rate: float = 0.1,
- kernel_size: int = 3,
- dilation: int = 1,
- padding: int = 0,
- ) -> None:
- super().__init__()
- self.channels = channels
- self.dropout_rate = dropout_rate
- self.kernel_size = kernel_size
- self.dilation = dilation
- self.padding = padding
- self.num_groups = num_groups
- self.activation = activation_function(activation)
- self.block = self._configure_block()
- self.residual_conv = nn.Sequential(
- nn.Conv2d(
- self.channels[0], self.channels[-1], kernel_size=3, stride=1, padding=1
- ),
- self.activation,
- )
-
- def _configure_block(self) -> nn.Sequential:
- block = []
- for i in range(len(self.channels) - 1):
- block += [
- nn.Dropout(p=self.dropout_rate),
- nn.GroupNorm(self.num_groups, self.channels[i]),
- self.activation,
- nn.Conv2d(
- self.channels[i],
- self.channels[i + 1],
- kernel_size=self.kernel_size,
- padding=self.padding,
- stride=1,
- dilation=self.dilation,
- ),
- ]
-
- return nn.Sequential(*block)
-
- def forward(self, x: Tensor) -> Tensor:
- """Apply the convolutional block."""
- residual = self.residual_conv(x)
- return self.block(x) + residual
-
-
-class _DownSamplingBlock(nn.Module):
- """Basic down sampling block."""
-
- def __init__(
- self,
- channels: List[int],
- activation: str,
- num_groups: int,
- pooling_kernel: Union[int, bool] = 2,
- dropout_rate: float = 0.1,
- kernel_size: int = 3,
- dilation: int = 1,
- padding: int = 0,
- ) -> None:
- super().__init__()
- self.conv_block = _ConvBlock(
- channels,
- activation,
- num_groups,
- dropout_rate,
- kernel_size,
- dilation,
- padding,
- )
- self.down_sampling = nn.MaxPool2d(pooling_kernel) if pooling_kernel else None
-
- def forward(self, x: Tensor) -> Tuple[Tensor, Tensor]:
- """Return the convolutional block output and a down sampled tensor."""
- x = self.conv_block(x)
- x_down = self.down_sampling(x) if self.down_sampling is not None else x
-
- return x_down, x
-
-
-class _UpSamplingBlock(nn.Module):
- """The upsampling block of the UNet."""
-
- def __init__(
- self,
- channels: List[int],
- activation: str,
- num_groups: int,
- scale_factor: int = 2,
- dropout_rate: float = 0.1,
- kernel_size: int = 3,
- dilation: int = 1,
- padding: int = 0,
- ) -> None:
- super().__init__()
- self.conv_block = _ConvBlock(
- channels,
- activation,
- num_groups,
- dropout_rate,
- kernel_size,
- dilation,
- padding,
- )
- self.up_sampling = nn.Upsample(
- scale_factor=scale_factor, mode="bilinear", align_corners=True
- )
-
- def forward(self, x: Tensor, x_skip: Optional[Tensor] = None) -> Tensor:
- """Apply the up sampling and convolutional block."""
- x = self.up_sampling(x)
- if x_skip is not None:
- x = torch.cat((x, x_skip), dim=1)
- return self.conv_block(x)
-
-
-class UNet(nn.Module):
- """UNet architecture."""
-
- def __init__(
- self,
- in_channels: int = 1,
- base_channels: int = 64,
- num_classes: int = 3,
- depth: int = 4,
- activation: str = "relu",
- num_groups: int = 8,
- dropout_rate: float = 0.1,
- pooling_kernel: int = 2,
- scale_factor: int = 2,
- kernel_size: Optional[List[int]] = None,
- dilation: Optional[List[int]] = None,
- padding: Optional[List[int]] = None,
- ) -> None:
- super().__init__()
- self.depth = depth
- self.num_groups = num_groups
-
- if kernel_size is not None and dilation is not None and padding is not None:
- if (
- len(kernel_size) != depth
- and len(dilation) != depth
- and len(padding) != depth
- ):
- raise RuntimeError(
- "Length of convolutional parameters does not match the depth."
- )
- self.kernel_size = kernel_size
- self.padding = padding
- self.dilation = dilation
-
- else:
- self.kernel_size = [3] * depth
- self.padding = [1] * depth
- self.dilation = [1] * depth
-
- self.dropout_rate = dropout_rate
- self.conv = nn.Conv2d(
- in_channels, base_channels, kernel_size=3, stride=1, padding=1
- )
-
- channels = [base_channels] + [base_channels * 2 ** i for i in range(depth)]
- self.encoder_blocks = self._configure_down_sampling_blocks(
- channels, activation, pooling_kernel
- )
- self.decoder_blocks = self._configure_up_sampling_blocks(
- channels, activation, scale_factor
- )
-
- self.head = nn.Conv2d(base_channels, num_classes, kernel_size=1)
-
- def _configure_down_sampling_blocks(
- self, channels: List[int], activation: str, pooling_kernel: int
- ) -> nn.ModuleList:
- blocks = nn.ModuleList([])
- for i in range(len(channels) - 1):
- pooling_kernel = pooling_kernel if i < self.depth - 1 else False
- dropout_rate = self.dropout_rate if i < 0 else 0
- blocks += [
- _DownSamplingBlock(
- [channels[i], channels[i + 1], channels[i + 1]],
- activation,
- self.num_groups,
- pooling_kernel,
- dropout_rate,
- self.kernel_size[i],
- self.dilation[i],
- self.padding[i],
- )
- ]
-
- return blocks
-
- def _configure_up_sampling_blocks(
- self, channels: List[int], activation: str, scale_factor: int,
- ) -> nn.ModuleList:
- channels.reverse()
- self.kernel_size.reverse()
- self.dilation.reverse()
- self.padding.reverse()
- return nn.ModuleList(
- [
- _UpSamplingBlock(
- [channels[i] + channels[i + 1], channels[i + 1], channels[i + 1]],
- activation,
- self.num_groups,
- scale_factor,
- self.dropout_rate,
- self.kernel_size[i],
- self.dilation[i],
- self.padding[i],
- )
- for i in range(len(channels) - 2)
- ]
- )
-
- def _encode(self, x: Tensor) -> List[Tensor]:
- x_skips = []
- for block in self.encoder_blocks:
- x, x_skip = block(x)
- x_skips.append(x_skip)
- return x_skips
-
- def _decode(self, x_skips: List[Tensor]) -> Tensor:
- x = x_skips[-1]
- for i, block in enumerate(self.decoder_blocks):
- x = block(x, x_skips[-(i + 2)])
- return x
-
- def forward(self, x: Tensor) -> Tensor:
- """Forward pass with the UNet model."""
- if len(x.shape) < 4:
- x = x[(None,) * (4 - len(x.shape))]
- x = self.conv(x)
- x_skips = self._encode(x)
- x = self._decode(x_skips)
- return self.head(x)
diff --git a/text_recognizer/networks/vit.py b/text_recognizer/networks/vit.py
deleted file mode 100644
index efb3701..0000000
--- a/text_recognizer/networks/vit.py
+++ /dev/null
@@ -1,150 +0,0 @@
-"""A Vision Transformer.
-
-Inspired by:
-https://openreview.net/pdf?id=YicbFdNTTy
-
-"""
-from typing import Optional, Tuple
-
-from einops import rearrange, repeat
-import torch
-from torch import nn
-from torch import Tensor
-
-from text_recognizer.networks.transformer import Transformer
-
-
-class ViT(nn.Module):
- """Transfomer for image to sequence prediction."""
-
- def __init__(
- self,
- num_encoder_layers: int,
- num_decoder_layers: int,
- hidden_dim: int,
- vocab_size: int,
- num_heads: int,
- expansion_dim: int,
- patch_dim: Tuple[int, int],
- image_size: Tuple[int, int],
- dropout_rate: float,
- trg_pad_index: int,
- max_len: int,
- activation: str = "gelu",
- ) -> None:
- super().__init__()
-
- self.trg_pad_index = trg_pad_index
- self.patch_dim = patch_dim
- self.num_patches = image_size[-1] // self.patch_dim[1]
-
- # Encoder
- self.patch_to_embedding = nn.Linear(
- self.patch_dim[0] * self.patch_dim[1], hidden_dim
- )
- self.cls_token = nn.Parameter(torch.randn(1, 1, hidden_dim))
- self.character_embedding = nn.Embedding(vocab_size, hidden_dim)
- self.pos_embedding = nn.Parameter(torch.randn(1, max_len, hidden_dim))
- self.dropout = nn.Dropout(dropout_rate)
- self._init()
-
- self.transformer = Transformer(
- num_encoder_layers,
- num_decoder_layers,
- hidden_dim,
- num_heads,
- expansion_dim,
- dropout_rate,
- activation,
- )
-
- self.head = nn.Sequential(nn.Linear(hidden_dim, vocab_size),)
-
- def _init(self) -> None:
- nn.init.normal_(self.character_embedding.weight, std=0.02)
- # nn.init.normal_(self.pos_embedding.weight, std=0.02)
-
- def _create_trg_mask(self, trg: Tensor) -> Tensor:
- # Move this outside the transformer.
- trg_pad_mask = (trg != self.trg_pad_index)[:, None, None]
- trg_len = trg.shape[1]
- trg_sub_mask = torch.tril(
- torch.ones((trg_len, trg_len), device=trg.device)
- ).bool()
- trg_mask = trg_pad_mask & trg_sub_mask
- return trg_mask
-
- def encoder(self, src: Tensor) -> Tensor:
- """Forward pass with the encoder of the transformer."""
- return self.transformer.encoder(src)
-
- def decoder(self, trg: Tensor, memory: Tensor, trg_mask: Tensor) -> Tensor:
- """Forward pass with the decoder of the transformer + classification head."""
- return self.head(
- self.transformer.decoder(trg=trg, memory=memory, trg_mask=trg_mask)
- )
-
- def extract_image_features(self, src: Tensor) -> Tensor:
- """Extracts image features with a backbone neural network.
-
- It seem like the winning idea was to swap channels and width dimension and collapse
- the height dimension. The transformer is learning like a baby with this implementation!!! :D
- Ohhhh, the joy I am experiencing right now!! Bring in the beers! :D :D :D
-
- Args:
- src (Tensor): Input tensor.
-
- Returns:
- Tensor: A input src to the transformer.
-
- """
- # If batch dimension is missing, it needs to be added.
- if len(src.shape) < 4:
- src = src[(None,) * (4 - len(src.shape))]
-
- patches = rearrange(
- src,
- "b c (h p1) (w p2) -> b (h w) (p1 p2 c)",
- p1=self.patch_dim[0],
- p2=self.patch_dim[1],
- )
-
- # From patches to encoded sequence.
- x = self.patch_to_embedding(patches)
- b, n, _ = x.shape
- cls_tokens = repeat(self.cls_token, "() n d -> b n d", b=b)
- x = torch.cat((cls_tokens, x), dim=1)
- x += self.pos_embedding[:, : (n + 1)]
- x = self.dropout(x)
-
- return x
-
- def target_embedding(self, trg: Tensor) -> Tuple[Tensor, Tensor]:
- """Encodes target tensor with embedding and postion.
-
- Args:
- trg (Tensor): Target tensor.
-
- Returns:
- Tuple[Tensor, Tensor]: Encoded target tensor and target mask.
-
- """
- _, n = trg.shape
- trg = self.character_embedding(trg.long())
- trg += self.pos_embedding[:, :n]
- return trg
-
- def decode_image_features(self, h: Tensor, trg: Optional[Tensor] = None) -> Tensor:
- """Takes images features from the backbone and decodes them with the transformer."""
- trg_mask = self._create_trg_mask(trg)
- trg = self.target_embedding(trg)
- out = self.transformer(h, trg, trg_mask=trg_mask)
-
- logits = self.head(out)
- return logits
-
- def forward(self, x: Tensor, trg: Optional[Tensor] = None) -> Tensor:
- """Forward pass with CNN transfomer."""
- h = self.extract_image_features(x)
- logits = self.decode_image_features(h, trg)
- return logits