1 files changed, 0 insertions, 165 deletions
diff --git a/text_recognizer/networks/image_transformer.py b/text_recognizer/networks/image_transformer.py
deleted file mode 100644
index a6aaca4..0000000
--- a/text_recognizer/networks/image_transformer.py
+++ /dev/null
@@ -1,165 +0,0 @@
-"""A Transformer with a cnn backbone.
-
-The network encodes a image with a convolutional backbone to a latent representation,
-i.e. feature maps. A 2d positional encoding is applied to the feature maps for
-spatial information. The resulting feature are then set to a transformer decoder
-together with the target tokens.
-
-TODO: Local attention for lower layer in attention.
-
-"""
-import importlib
-import math
-from typing import Dict, Optional, Union, Sequence, Type
-
-from einops import rearrange
-from omegaconf import DictConfig, OmegaConf
-import torch
-from torch import nn
-from torch import Tensor
-
-from text_recognizer.data.emnist import NUM_SPECIAL_TOKENS
-from text_recognizer.networks.transformer import (
-    Decoder,
-    DecoderLayer,
-    PositionalEncoding,
-    PositionalEncoding2D,
-    target_padding_mask,
-)
-
-NUM_WORD_PIECES = 1000
-
-
-class ImageTransformer(nn.Module):
-    def __init__(
-        self,
-        input_shape: Sequence[int],
-        output_shape: Sequence[int],
-        encoder: Union[DictConfig, Dict],
-        vocab_size: Optional[int] = None,
-        num_decoder_layers: int = 4,
-        hidden_dim: int = 256,
-        num_heads: int = 4,
-        expansion_dim: int = 1024,
-        dropout_rate: float = 0.1,
-        transformer_activation: str = "glu",
-    ) -> None:
-        self.vocab_size = (
-            NUM_WORD_PIECES + NUM_SPECIAL_TOKENS if vocab_size is None else vocab_size
-        )
-        self.hidden_dim = hidden_dim
-        self.max_output_length = output_shape[0]
-
-        # Image backbone
-        self.encoder = self._configure_encoder(encoder)
-        self.feature_map_encoding = PositionalEncoding2D(
-            hidden_dim=hidden_dim, max_h=input_shape[1], max_w=input_shape[2]
-        )
-
-        # Target token embedding
-        self.trg_embedding = nn.Embedding(self.vocab_size, hidden_dim)
-        self.trg_position_encoding = PositionalEncoding(hidden_dim, dropout_rate)
-
-        # Transformer decoder
-        self.decoder = Decoder(
-            decoder_layer=DecoderLayer(
-                hidden_dim=hidden_dim,
-                num_heads=num_heads,
-                expansion_dim=expansion_dim,
-                dropout_rate=dropout_rate,
-                activation=transformer_activation,
-            ),
-            num_layers=num_decoder_layers,
-            norm=nn.LayerNorm(hidden_dim),
-        )
-
-        # Classification head
-        self.head = nn.Linear(hidden_dim, self.vocab_size)
-
-        # Initialize weights
-        self._init_weights()
-
-    def _init_weights(self) -> None:
-        """Initialize network weights."""
-        self.trg_embedding.weight.data.uniform_(-0.1, 0.1)
-        self.head.bias.data.zero_()
-        self.head.weight.data.uniform_(-0.1, 0.1)
-
-        nn.init.kaiming_normal_(
-            self.feature_map_encoding.weight.data,
-            a=0,
-            mode="fan_out",
-            nonlinearity="relu",
-        )
-        if self.feature_map_encoding.bias is not None:
-            _, fan_out = nn.init._calculate_fan_in_and_fan_out(
-                self.feature_map_encoding.weight.data
-            )
-            bound = 1 / math.sqrt(fan_out)
-            nn.init.normal_(self.feature_map_encoding.bias, -bound, bound)
-
-    @staticmethod
-    def _configure_encoder(encoder: Union[DictConfig, Dict]) -> Type[nn.Module]:
-        encoder = OmegaConf.create(encoder)
-        network_module = importlib.import_module("text_recognizer.networks")
-        encoder_class = getattr(network_module, encoder.type)
-        return encoder_class(**encoder.args)
-
-    def encode(self, image: Tensor) -> Tensor:
-        """Extracts image features with backbone.
-
-        Args:
-            image (Tensor): Image(s) of handwritten text.
-
-        Retuns:
-            Tensor: Image features.
-
-        Shapes:
-            - image: :math: `(B, C, H, W)`
-            - latent: :math: `(B, T, C)`
-
-        """
-        # Extract image features.
-        image_features = self.encoder(image)
-
-        # Add 2d encoding to the feature maps.
-        image_features = self.feature_map_encoding(image_features)
-
-        # Collapse features maps height and width.
-        image_features = rearrange(image_features, "b c h w -> b (h w) c")
-        return image_features
-
-    def decode(self, memory: Tensor, trg: Tensor) -> Tensor:
-        """Decodes image features with transformer decoder."""
-        trg_mask = target_padding_mask(trg=trg, pad_index=self.pad_index)
-        trg = self.trg_embedding(trg) * math.sqrt(self.hidden_dim)
-        trg = self.trg_position_encoding(trg)
-        out = self.decoder(trg=trg, memory=memory, trg_mask=trg_mask, memory_mask=None)
-        logits = self.head(out)
-        return logits
-
-    def predict(self, image: Tensor) -> Tensor:
-        """Transcribes text in image(s)."""
-        bsz = image.shape[0]
-        image_features = self.encode(image)
-
-        output_tokens = (
-            (torch.ones((bsz, self.max_output_length)) * self.pad_index)
-            .type_as(image)
-            .long()
-        )
-        output_tokens[:, 0] = self.start_index
-        for i in range(1, self.max_output_length):
-            trg = output_tokens[:, :i]
-            output = self.decode(image_features, trg)
-            output = torch.argmax(output, dim=-1)
-            output_tokens[:, i] = output[-1:]
-
-        # Set all tokens after end token to be padding.
-        for i in range(1, self.max_output_length):
-            indices = output_tokens[:, i - 1] == self.end_index | (
-                output_tokens[:, i - 1] == self.pad_index
-            )
-            output_tokens[indices, i] = self.pad_index
-
-        return output_tokens