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author | aktersnurra <gustaf.rydholm@gmail.com> | 2020-11-12 23:42:03 +0100 |
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committer | aktersnurra <gustaf.rydholm@gmail.com> | 2020-11-12 23:42:03 +0100 |
commit | 8fdb6435e15703fa5b76df19728d905650ee1aef (patch) | |
tree | be3bec9e5cab4ef7f9d94528d102e57ce9b16c3f /src/text_recognizer/networks/neural_machine_reader.py | |
parent | dc28cbe2b4ed77be92ee8b2b69a20689c3bf02a4 (diff) | |
parent | 6cb08a110620ee09fe9d8a5d008197a801d025df (diff) |
Working cnn transformer.
Diffstat (limited to 'src/text_recognizer/networks/neural_machine_reader.py')
-rw-r--r-- | src/text_recognizer/networks/neural_machine_reader.py | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/src/text_recognizer/networks/neural_machine_reader.py b/src/text_recognizer/networks/neural_machine_reader.py new file mode 100644 index 0000000..7f8c49b --- /dev/null +++ b/src/text_recognizer/networks/neural_machine_reader.py @@ -0,0 +1,201 @@ +"""Sequence to sequence network with RNN cells.""" +# from typing import Dict, Optional, Tuple + +# from einops import rearrange +# from einops.layers.torch import Rearrange +# import torch +# from torch import nn +# from torch import Tensor + +# from text_recognizer.networks.util import configure_backbone + + +# class Encoder(nn.Module): +# def __init__( +# self, +# embedding_dim: int, +# encoder_dim: int, +# decoder_dim: int, +# dropout_rate: float = 0.1, +# ) -> None: +# super().__init__() +# self.rnn = nn.GRU( +# input_size=embedding_dim, hidden_size=encoder_dim, bidirectional=True +# ) +# self.fc = nn.Sequential( +# nn.Linear(in_features=2 * encoder_dim, out_features=decoder_dim), nn.Tanh() +# ) +# self.dropout = nn.Dropout(p=dropout_rate) + +# def forward(self, x: Tensor) -> Tuple[Tensor, Tensor]: +# """Encodes a sequence of tensors with a bidirectional GRU. + +# Args: +# x (Tensor): A input sequence. + +# Shape: +# - x: :math:`(T, N, E)`. +# - output[0]: :math:`(T, N, 2 * E)`. +# - output[1]: :math:`(T, N, D)`. + +# where T is the sequence length, N is the batch size, E is the +# embedding/encoder dimension, and D is the decoder dimension. + +# Returns: +# Tuple[Tensor, Tensor]: The encoder output and the hidden state of the +# encoder. + +# """ + +# output, hidden = self.rnn(x) + +# # Get the hidden state from the forward and backward rnn. +# hidden_state = torch.cat((hidden[-2, :, :], hidden[-1, :, :]), dim=1) + +# # Apply fully connected layer and tanh activation. +# hidden_state = self.fc(hidden_state) + +# return output, hidden_state + + +# class Attention(nn.Module): +# def __init__(self, encoder_dim: int, decoder_dim: int) -> None: +# super().__init__() +# self.atten = nn.Linear( +# in_features=2 * encoder_dim + decoder_dim, out_features=decoder_dim +# ) +# self.value = nn.Linear(in_features=decoder_dim, out_features=1, bias=False) + +# def forward(self, hidden_state: Tensor, encoder_outputs: Tensor) -> Tensor: +# """Short summary. + +# Args: +# hidden_state (Tensor): Description of parameter `h`. +# encoder_outputs (Tensor): Description of parameter `enc_out`. + +# Shape: +# - x: :math:`(T, N, E)`. +# - output[0]: :math:`(T, N, 2 * E)`. +# - output[1]: :math:`(T, N, D)`. + +# where T is the sequence length, N is the batch size, E is the +# embedding/encoder dimension, and D is the decoder dimension. + +# Returns: +# Tensor: Description of returned object. + +# """ +# t, b = enc_out.shape[:2] +# # repeat decoder hidden state src_len times +# hidden_state = hidden_state.unsqueeze(1).repeat(1, t, 1) + +# encoder_outputs = rearrange(encoder_outputs, "t b e2 -> b t e2") + +# # Calculate the energy between the decoders previous hidden state and the +# # encoders hidden states. +# energy = torch.tanh( +# self.attn(torch.cat((hidden_state, encoder_outputs), dim=2)) +# ) + +# attention = self.value(energy).squeeze(2) + +# # Apply softmax on the attention to squeeze it between 0 and 1. +# attention = F.softmax(attention, dim=1) + +# return attention + + +# class Decoder(nn.Module): +# def __init__( +# self, +# embedding_dim: int, +# encoder_dim: int, +# decoder_dim: int, +# output_dim: int, +# dropout_rate: float = 0.1, +# ) -> None: +# super().__init__() +# self.output_dim = output_dim +# self.embedding = nn.Embedding(output_dim, embedding_dim) +# self.attention = Attention(encoder_dim, decoder_dim) +# self.rnn = nn.GRU( +# input_size=2 * encoder_dim + embedding_dim, hidden_size=decoder_dim +# ) + +# self.head = nn.Linear( +# in_features=2 * encoder_dim + embedding_dim + decoder_dim, +# out_features=output_dim, +# ) +# self.dropout = nn.Dropout(p=dropout_rate) + +# def forward( +# self, trg: Tensor, hidden_state: Tensor, encoder_outputs: Tensor +# ) -> Tensor: +# # input = [batch size] +# # hidden = [batch size, dec hid dim] +# # encoder_outputs = [src len, batch size, enc hid dim * 2] +# trg = trg.unsqueeze(0) +# trg_embedded = self.dropout(self.embedding(trg)) + +# a = self.attention(hidden_state, encoder_outputs) + +# weighted = torch.bmm(a, encoder_outputs) + +# # Permutate the tensor. +# weighted = rearrange(weighted, "b a e2 -> a b e2") + +# rnn_input = torch.cat((trg_embedded, weighted), dim=2) + +# output, hidden = self.rnn(rnn_input, hidden.unsqueeze(0)) + +# # seq len, n layers and n directions will always be 1 in this decoder, therefore: +# # output = [1, batch size, dec hid dim] +# # hidden = [1, batch size, dec hid dim] +# # this also means that output == hidden +# assert (output == hidden).all() + +# trg_embedded = trg_embedded.squeeze(0) +# output = output.squeeze(0) +# weighted = weighted.squeeze(0) + +# logits = self.fc_out(torch.cat((output, weighted, trg_embedded), dim=1)) + +# # prediction = [batch size, output dim] + +# return logits, hidden.squeeze(0) + + +# class NeuralMachineReader(nn.Module): +# def __init__( +# self, +# embedding_dim: int, +# encoder_dim: int, +# decoder_dim: int, +# output_dim: int, +# backbone: Optional[str] = None, +# backbone_args: Optional[Dict] = None, +# adaptive_pool_dim: Tuple = (None, 1), +# dropout_rate: float = 0.1, +# teacher_forcing_ratio: float = 0.5, +# ) -> None: +# super().__init__() + +# self.backbone = configure_backbone(backbone, backbone_args) +# self.adaptive_pool = nn.AdaptiveAvgPool2d((adaptive_pool_dim)) + +# self.encoder = Encoder(embedding_dim, encoder_dim, decoder_dim, dropout_rate) +# self.decoder = Decoder( +# embedding_dim, encoder_dim, decoder_dim, output_dim, dropout_rate +# ) +# self.teacher_forcing_ratio = teacher_forcing_ratio + +# def extract_image_features(self, x: Tensor) -> Tensor: +# x = self.backbone(x) +# x = rearrange(x, "b c h w -> b w c h") +# x = self.adaptive_pool(x) +# x = x.squeeze(3) + +# def forward(self, x: Tensor, trg: Tensor) -> Tensor: +# # x = [batch size, height, width] +# # trg = [trg len, batch size] +# z = self.extract_image_features(x) |