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authorGustaf Rydholm <gustaf.rydholm@gmail.com>2021-03-31 21:55:10 +0200
committerGustaf Rydholm <gustaf.rydholm@gmail.com>2021-03-31 21:55:10 +0200
commit3196144ec99e803cef218295ddea592748931c57 (patch)
tree867d38ed08c78b8186fdd9a8abab4257f14d05c7 /text_recognizer/data/util.py
parentd21594211e29c40c135b753e33b248b0737cd76f (diff)
Removing legacy code
Diffstat (limited to 'text_recognizer/data/util.py')
-rw-r--r--text_recognizer/data/util.py209
1 files changed, 0 insertions, 209 deletions
diff --git a/text_recognizer/data/util.py b/text_recognizer/data/util.py
deleted file mode 100644
index da87756..0000000
--- a/text_recognizer/data/util.py
+++ /dev/null
@@ -1,209 +0,0 @@
-"""Util functions for datasets."""
-import hashlib
-import json
-import os
-from pathlib import Path
-import string
-from typing import Dict, List, Optional, Union
-from urllib.request import urlretrieve
-
-from loguru import logger
-import numpy as np
-import torch
-from torch import Tensor
-from torchvision.datasets import EMNIST
-from tqdm import tqdm
-
-DATA_DIRNAME = Path(__file__).resolve().parents[3] / "data"
-ESSENTIALS_FILENAME = Path(__file__).resolve().parents[0] / "emnist_essentials.json"
-
-
-def save_emnist_essentials(emnsit_dataset: EMNIST = EMNIST) -> None:
- """Extract and saves EMNIST essentials."""
- labels = emnsit_dataset.classes
- labels.sort()
- mapping = [(i, str(label)) for i, label in enumerate(labels)]
- essentials = {
- "mapping": mapping,
- "input_shape": tuple(np.array(emnsit_dataset[0][0]).shape[:]),
- }
- logger.info("Saving emnist essentials...")
- with open(ESSENTIALS_FILENAME, "w") as f:
- json.dump(essentials, f)
-
-
-def download_emnist() -> None:
- """Download the EMNIST dataset via the PyTorch class."""
- logger.info(f"Data directory is: {DATA_DIRNAME}")
- dataset = EMNIST(root=DATA_DIRNAME, split="byclass", download=True)
- save_emnist_essentials(dataset)
-
-
-class EmnistMapper:
- """Mapper between network output to Emnist character."""
-
- def __init__(
- self,
- pad_token: str,
- init_token: Optional[str] = None,
- eos_token: Optional[str] = None,
- lower: bool = False,
- ) -> None:
- """Loads the emnist essentials file with the mapping and input shape."""
- self.init_token = init_token
- self.pad_token = pad_token
- self.eos_token = eos_token
- self.lower = lower
-
- self.essentials = self._load_emnist_essentials()
- # Load dataset information.
- self._mapping = dict(self.essentials["mapping"])
- self._augment_emnist_mapping()
- self._inverse_mapping = {v: k for k, v in self.mapping.items()}
- self._num_classes = len(self.mapping)
- self._input_shape = self.essentials["input_shape"]
-
- def __call__(self, token: Union[str, int, np.uint8, Tensor]) -> Union[str, int]:
- """Maps the token to emnist character or character index.
-
- If the token is an integer (index), the method will return the Emnist character corresponding to that index.
- If the token is a str (Emnist character), the method will return the corresponding index for that character.
-
- Args:
- token (Union[str, int, np.uint8, Tensor]): Either a string or index (integer).
-
- Returns:
- Union[str, int]: The mapping result.
-
- Raises:
- KeyError: If the index or string does not exist in the mapping.
-
- """
- if (
- (isinstance(token, np.uint8) or isinstance(token, int))
- or torch.is_tensor(token)
- and int(token) in self.mapping
- ):
- return self.mapping[int(token)]
- elif isinstance(token, str) and token in self._inverse_mapping:
- return self._inverse_mapping[token]
- else:
- raise KeyError(f"Token {token} does not exist in the mappings.")
-
- @property
- def mapping(self) -> Dict:
- """Returns the mapping between index and character."""
- return self._mapping
-
- @property
- def inverse_mapping(self) -> Dict:
- """Returns the mapping between character and index."""
- return self._inverse_mapping
-
- @property
- def num_classes(self) -> int:
- """Returns the number of classes in the dataset."""
- return self._num_classes
-
- @property
- def input_shape(self) -> List[int]:
- """Returns the input shape of the Emnist characters."""
- return self._input_shape
-
- def _load_emnist_essentials(self) -> Dict:
- """Load the EMNIST mapping."""
- with open(str(ESSENTIALS_FILENAME)) as f:
- essentials = json.load(f)
- return essentials
-
- def _augment_emnist_mapping(self) -> None:
- """Augment the mapping with extra symbols."""
- # Extra symbols in IAM dataset
- if self.lower:
- self._mapping = {
- k: str(v)
- for k, v in enumerate(list(range(10)) + list(string.ascii_lowercase))
- }
-
- extra_symbols = [
- " ",
- "!",
- '"',
- "#",
- "&",
- "'",
- "(",
- ")",
- "*",
- "+",
- ",",
- "-",
- ".",
- "/",
- ":",
- ";",
- "?",
- ]
-
- # padding symbol, and acts as blank symbol as well.
- extra_symbols.append(self.pad_token)
-
- if self.init_token is not None:
- extra_symbols.append(self.init_token)
-
- if self.eos_token is not None:
- extra_symbols.append(self.eos_token)
-
- max_key = max(self.mapping.keys())
- extra_mapping = {}
- for i, symbol in enumerate(extra_symbols):
- extra_mapping[max_key + 1 + i] = symbol
-
- self._mapping = {**self.mapping, **extra_mapping}
-
-
-def compute_sha256(filename: Union[Path, str]) -> str:
- """Returns the SHA256 checksum of a file."""
- with open(filename, "rb") as f:
- return hashlib.sha256(f.read()).hexdigest()
-
-
-class TqdmUpTo(tqdm):
- """TQDM progress bar when downloading files.
-
- From https://github.com/tqdm/tqdm/blob/master/examples/tqdm_wget.py
-
- """
-
- def update_to(
- self, blocks: int = 1, block_size: int = 1, total_size: Optional[int] = None
- ) -> None:
- """Updates the progress bar.
-
- Args:
- blocks (int): Number of blocks transferred so far. Defaults to 1.
- block_size (int): Size of each block, in tqdm units. Defaults to 1.
- total_size (Optional[int]): Total size in tqdm units. Defaults to None.
- """
- if total_size is not None:
- self.total = total_size # pylint: disable=attribute-defined-outside-init
- self.update(blocks * block_size - self.n)
-
-
-def download_url(url: str, filename: str) -> None:
- """Downloads a file from url to filename, with a progress bar."""
- with TqdmUpTo(unit="B", unit_scale=True, unit_divisor=1024, miniters=1) as t:
- urlretrieve(url, filename, reporthook=t.update_to, data=None) # nosec
-
-
-def _download_raw_dataset(metadata: Dict) -> None:
- if os.path.exists(metadata["filename"]):
- return
- logger.info(f"Downloading raw dataset from {metadata['url']}...")
- download_url(metadata["url"], metadata["filename"])
- logger.info("Computing SHA-256...")
- sha256 = compute_sha256(metadata["filename"])
- if sha256 != metadata["sha256"]:
- raise ValueError(
- "Downloaded data file SHA-256 does not match that listed in metadata document."
- )