# -*- coding: utf-8 -*-
"""
easyocr.py - A wrapper for easyocr to convert pdf to images to text
"""
import logging
from pathlib import Path
logging.basicConfig(
level=logging.INFO,
format="%(asctime)s %(levelname)s %(message)s",
datefmt="%m/%d/%Y %I:%M:%S",
)
import os
import pprint as pp
import re
import shutil
import time
from datetime import date, datetime
from os.path import basename, dirname, join
from pathlib import Path
from cleantext import clean
from doctr.io import DocumentFile
from doctr.models import ocr_predictor
from libretranslatepy import LibreTranslateAPI
from natsort import natsorted
from spellchecker import SpellChecker
from tqdm.auto import tqdm
def simple_rename(filepath, target_ext=".txt"):
_fp = Path(filepath)
basename = _fp.stem
return f"OCR_{basename}_{target_ext}"
def rm_local_text_files(name_contains="RESULT_"):
"""
rm_local_text_files - remove local text files
Args:
name_contains (str, optional): [description]. Defaults to "OCR_".
"""
files = [
f
for f in Path.cwd().iterdir()
if f.is_file() and f.suffix == ".txt" and name_contains in f.name
]
logging.info(f"removing {len(files)} text files")
for f in files:
os.remove(f)
logging.info("done")
def corr(
s: str,
add_space_when_numerics=False,
exceptions=["e.g.", "i.e.", "etc.", "cf.", "vs.", "p."],
) -> str:
"""corrects spacing in a string
Args:
s (str): the string to correct
add_space_when_numerics (bool, optional): [add a space when a period is between two numbers, example 5.73]. Defaults to False.
exceptions (list, optional): [do not change these substrings]. Defaults to ['e.g.', 'i.e.', 'etc.', 'cf.', 'vs.', 'p.'].
Returns:
str: the corrected string
"""
if add_space_when_numerics:
s = re.sub(r"(\d)\.(\d)", r"\1. \2", s)
s = re.sub(r"\s+", " ", s)
s = re.sub(r'\s([?.!"](?:\s|$))', r"\1", s)
# fix space before apostrophe
s = re.sub(r"\s\'", r"'", s)
# fix space after apostrophe
s = re.sub(r"'\s", r"'", s)
# fix space before comma
s = re.sub(r"\s,", r",", s)
for e in exceptions:
expected_sub = re.sub(r"\s", "", e)
s = s.replace(expected_sub, e)
return s
def fix_punct_spaces(string):
"""
fix_punct_spaces - replace spaces around punctuation with punctuation. For example, "hello , there" -> "hello, there"
Parameters
----------
string : str, required, input string to be corrected
Returns
-------
str, corrected string
"""
fix_spaces = re.compile(r"\s*([?!.,]+(?:\s+[?!.,]+)*)\s*")
string = fix_spaces.sub(lambda x: "{} ".format(x.group(1).replace(" ", "")), string)
string = string.replace(" ' ", "'")
string = string.replace(' " ', '"')
return string.strip()
def clean_OCR(ugly_text: str):
"""
clean_OCR - clean the OCR text files.
Parameters
----------
ugly_text : str, required, input string to be cleaned
Returns
-------
str, cleaned string
"""
# Remove all the newlines.
cleaned_text = ugly_text.replace("\n", " ")
# Remove all the tabs.
cleaned_text = cleaned_text.replace("\t", " ")
# Remove all the double spaces.
cleaned_text = cleaned_text.replace(" ", " ")
# Remove all the spaces at the beginning of the text.
cleaned_text = cleaned_text.lstrip()
# remove all instances of "- " and " - "
cleaned_text = cleaned_text.replace("- ", "")
cleaned_text = cleaned_text.replace(" -", "")
return fix_punct_spaces(cleaned_text)
def move2completed(from_dir, filename, new_folder="completed", verbose=False):
# this is the better version
old_filepath = join(from_dir, filename)
new_filedirectory = join(from_dir, new_folder)
if not os.path.isdir(new_filedirectory):
os.mkdir(new_filedirectory)
if verbose:
print("created new directory for files at: \n", new_filedirectory)
new_filepath = join(new_filedirectory, filename)
try:
shutil.move(old_filepath, new_filepath)
logging.info("successfully moved the file {} to */completed.".format(filename))
except:
logging.info(
"ERROR! unable to move file to \n{}. Please investigate".format(
new_filepath
)
)
"""## pdf2text functions
"""
custom_replace_list = {
"t0": "to",
"'$": "'s",
",,": ", ",
"_ ": " ",
" '": "'",
}
replace_corr_exceptions = {
"i. e.": "i.e.",
"e. g.": "e.g.",
"e. g": "e.g.",
" ,": ",",
}
spell = SpellChecker()
def check_word_spelling(word: str) -> bool:
"""
check_word_spelling - check the spelling of a word
Args:
word (str): word to check
Returns:
bool: True if word is spelled correctly, False if not
"""
misspelled = spell.unknown([word])
return len(misspelled) == 0
def eval_and_replace(text: str, match_token: str = "- ") -> str:
"""
eval_and_replace - conditionally replace all instances of a substring in a string based on whether the eliminated substring results in a valid word
Args:
text (str): text to evaluate
match_token (str, optional): token to replace. Defaults to "- ".
Returns:
str: text with replaced tokens
"""
if match_token not in text:
return text
else:
while True:
full_before_text = text.split(match_token, maxsplit=1)[0]
before_text = [
char for char in full_before_text.split()[-1] if char.isalpha()
]
before_text = "".join(before_text)
full_after_text = text.split(match_token, maxsplit=1)[-1]
after_text = [char for char in full_after_text.split()[0] if char.isalpha()]
after_text = "".join(after_text)
full_text = before_text + after_text
if check_word_spelling(full_text):
text = full_before_text + full_after_text
else:
text = full_before_text + " " + full_after_text
if match_token not in text:
break
return text
def cleantxt_ocr(ugly_text, lower=False, lang: str = "en") -> str:
"""
cleantxt_ocr - clean text from OCR
Args:
ugly_text (str): text to clean
lower (bool, optional): _description_. Defaults to False.
lang (str, optional): _description_. Defaults to "en".
Returns:
str: cleaned text
"""
# a wrapper for clean text with options different than default
# https://pypi.org/project/clean-text/
cleaned_text = clean(
ugly_text,
fix_unicode=True, # fix various unicode errors
to_ascii=True, # transliterate to closest ASCII representation
lower=lower, # lowercase text
no_line_breaks=True, # fully strip line breaks as opposed to only normalizing them
no_urls=True, # replace all URLs with a special token
no_emails=True, # replace all email addresses with a special token
no_phone_numbers=False, # replace all phone numbers with a special token
no_numbers=False, # replace all numbers with a special token
no_digits=False, # replace all digits with a special token
no_currency_symbols=False, # replace all currency symbols with a special token
no_punct=False, # remove punctuations
replace_with_punct="", # instead of removing punctuations you may replace them
replace_with_url="<URL>",
replace_with_email="<EMAIL>",
replace_with_phone_number="<PHONE>",
replace_with_number="<NUM>",
replace_with_digit="0",
replace_with_currency_symbol="<CUR>",
lang=lang, # set to 'de' for German special handling
)
return cleaned_text
def format_ocr_out(OCR_data):
if isinstance(OCR_data, list):
text = " ".join(OCR_data)
else:
text = str(OCR_data)
_clean = cleantxt_ocr(text)
return corr(_clean)
def postprocess(text: str) -> str:
"""to be used after recombining the lines"""
proc = corr(cleantxt_ocr(text))
for k, v in custom_replace_list.items():
proc = proc.replace(str(k), str(v))
proc = corr(proc)
for k, v in replace_corr_exceptions.items():
proc = proc.replace(str(k), str(v))
return eval_and_replace(proc)
def result2text(result, as_text=False) -> str or list:
"""Convert OCR result to text"""
full_doc = []
for i, page in enumerate(result.pages, start=1):
text = ""
for block in page.blocks:
text += "\n\t"
for line in block.lines:
for word in line.words:
# print(dir(word))
text += word.value + " "
full_doc.append(text)
return "\n".join(full_doc) if as_text else full_doc
def convert_PDF_to_Text(
PDF_file,
ocr_model=None,
max_pages: int = 20,
):
st = time.perf_counter()
PDF_file = Path(PDF_file)
ocr_model = ocr_predictor(pretrained=True) if ocr_model is None else ocr_model
logging.info(f"starting OCR on {PDF_file.name}")
doc = DocumentFile.from_pdf(PDF_file)
truncated = False
if len(doc) > max_pages:
logging.warning(
f"PDF has {len(doc)} pages, which is more than {max_pages}.. truncating"
)
doc = doc[:max_pages]
truncated = True
# Analyze
logging.info(f"running OCR on {len(doc)} pages")
result = ocr_model(doc)
raw_text = result2text(result)
proc_text = [format_ocr_out(r) for r in raw_text]
fin_text = [postprocess(t) for t in proc_text]
ocr_results = "\n\n".join(fin_text)
fn_rt = time.perf_counter() - st
logging.info("OCR complete")
results_dict = {
"num_pages": len(doc),
"runtime": round(fn_rt, 2),
"date": str(date.today()),
"converted_text": ocr_results,
"truncated": truncated,
"length": len(ocr_results),
}
return results_dict
# @title translation functions
lt = LibreTranslateAPI("https://translate.astian.org/")
def translate_text(text, source_l, target_l="en"):
return str(lt.translate(text, source_l, target_l))
def translate_doc(filepath, lang_start, lang_end="en", verbose=False):
"""translate a document from lang_start to lang_end
{'code': 'en', 'name': 'English'},
{'code': 'fr', 'name': 'French'},
{'code': 'de', 'name': 'German'},
{'code': 'it', 'name': 'Italian'},"""
src_folder = dirname(filepath)
src_folder = Path(src_folder)
trgt_folder = src_folder / f"translated_{lang_end}"
trgt_folder.mkdir(exist_ok=True)
with open(filepath, "r", encoding="utf-8", errors="ignore") as f:
foreign_t = f.readlines()
in_name = basename(filepath)
translated_doc = []
for line in tqdm(
foreign_t, total=len(foreign_t), desc="translating {}...".format(in_name[:10])
):
translated_line = translate_text(line, lang_start, lang_end)
translated_doc.append(translated_line)
t_out_name = "[To {}]".format(lang_end) + simple_rename(in_name) + ".txt"
out_path = join(trgt_folder, t_out_name)
with open(out_path, "w", encoding="utf-8", errors="ignore") as f_o:
f_o.writelines(translated_doc)
if verbose:
print("finished translating the document! - ", datetime.now())
return out_path