# Copyright 2022 The OpenAI team and The HuggingFace Team. All rights reserved.
# Most of the code is copy pasted from the original whisper repository
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import re
import unicodedata
from fractions import Fraction
from typing import Iterator, List, Match, Optional, Union
import regex
# non-ASCII letters that are not separated by "NFKD" normalization
ADDITIONAL_DIACRITICS = {
"œ": "oe",
"Œ": "OE",
"ø": "o",
"Ø": "O",
"æ": "ae",
"Æ": "AE",
"ß": "ss",
"ẞ": "SS",
"đ": "d",
"Đ": "D",
"ð": "d",
"Ð": "D",
"þ": "th",
"Þ": "th",
"ł": "l",
"Ł": "L",
}
def remove_symbols_and_diacritics(s: str, keep=""):
"""
Replace any other markers, symbols, and punctuations with a space, and drop any diacritics (category 'Mn' and some
manual mappings)
"""
def replace_character(char):
if char in keep:
return char
elif char in ADDITIONAL_DIACRITICS:
return ADDITIONAL_DIACRITICS[char]
elif unicodedata.category(char) == "Mn":
return ""
elif unicodedata.category(char)[0] in "MSP":
return " "
return char
return "".join(replace_character(c) for c in unicodedata.normalize("NFKD", s))
def remove_symbols(s: str):
"""
Replace any other markers, symbols, punctuations with a space, keeping diacritics
"""
return "".join(" " if unicodedata.category(c)[0] in "MSP" else c for c in unicodedata.normalize("NFKC", s))
class BasicTextNormalizer:
def __init__(self, remove_diacritics: bool = False, split_letters: bool = False):
self.clean = remove_symbols_and_diacritics if remove_diacritics else remove_symbols
self.split_letters = split_letters
def __call__(self, s: str):
s = s.lower()
s = re.sub(r"[<\[][^>\]]*[>\]]", "", s) # remove words between brackets
s = re.sub(r"\(([^)]+?)\)", "", s) # remove words between parenthesis
s = self.clean(s).lower()
if self.split_letters:
s = " ".join(regex.findall(r"\X", s, regex.U))
s = re.sub(r"\s+", " ", s) # replace any successive whitespace characters with a space
return s
class EnglishNumberNormalizer:
"""
Convert any spelled-out numbers into arabic numbers, while handling:
- remove any commas
- keep the suffixes such as: `1960s`, `274th`, `32nd`, etc.
- spell out currency symbols after the number. e.g. `$20 million` -> `20000000 dollars`
- spell out `one` and `ones`
- interpret successive single-digit numbers as nominal: `one oh one` -> `101`
"""
def __init__(self):
super().__init__()
self.zeros = {"o", "oh", "zero"}
# fmt: off
self.ones = {
name: i
for i, name in enumerate(
["one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten", "eleven", "twelve", "thirteen", "fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen"],
start=1,
)
}
# fmt: on
self.ones_plural = {
"sixes" if name == "six" else name + "s": (value, "s") for name, value in self.ones.items()
}
self.ones_ordinal = {
"zeroth": (0, "th"),
"first": (1, "st"),
"second": (2, "nd"),
"third": (3, "rd"),
"fifth": (5, "th"),
"twelfth": (12, "th"),
**{
name + ("h" if name.endswith("t") else "th"): (value, "th")
for name, value in self.ones.items()
if value > 3 and value != 5 and value != 12
},
}
self.ones_suffixed = {**self.ones_plural, **self.ones_ordinal}
self.tens = {
"twenty": 20,
"thirty": 30,
"forty": 40,
"fifty": 50,
"sixty": 60,
"seventy": 70,
"eighty": 80,
"ninety": 90,
}
self.tens_plural = {name.replace("y", "ies"): (value, "s") for name, value in self.tens.items()}
self.tens_ordinal = {name.replace("y", "ieth"): (value, "th") for name, value in self.tens.items()}
self.tens_suffixed = {**self.tens_plural, **self.tens_ordinal}
self.multipliers = {
"hundred": 100,
"thousand": 1_000,
"million": 1_000_000,
"billion": 1_000_000_000,
"trillion": 1_000_000_000_000,
"quadrillion": 1_000_000_000_000_000,
"quintillion": 1_000_000_000_000_000_000,
"sextillion": 1_000_000_000_000_000_000_000,
"septillion": 1_000_000_000_000_000_000_000_000,
"octillion": 1_000_000_000_000_000_000_000_000_000,
"nonillion": 1_000_000_000_000_000_000_000_000_000_000,
"decillion": 1_000_000_000_000_000_000_000_000_000_000_000,
}
self.multipliers_plural = {name + "s": (value, "s") for name, value in self.multipliers.items()}
self.multipliers_ordinal = {name + "th": (value, "th") for name, value in self.multipliers.items()}
self.multipliers_suffixed = {**self.multipliers_plural, **self.multipliers_ordinal}
self.decimals = {*self.ones, *self.tens, *self.zeros}
self.preceding_prefixers = {
"minus": "-",
"negative": "-",
"plus": "+",
"positive": "+",
}
self.following_prefixers = {
"pound": "£",
"pounds": "£",
"euro": "€",
"euros": "€",
"dollar": "$",
"dollars": "$",
"cent": "¢",
"cents": "¢",
}
self.prefixes = set(list(self.preceding_prefixers.values()) + list(self.following_prefixers.values()))
self.suffixers = {
"per": {"cent": "%"},
"percent": "%",
}
self.specials = {"and", "double", "triple", "point"}
self.words = {
key
for mapping in [
self.zeros,
self.ones,
self.ones_suffixed,
self.tens,
self.tens_suffixed,
self.multipliers,
self.multipliers_suffixed,
self.preceding_prefixers,
self.following_prefixers,
self.suffixers,
self.specials,
]
for key in mapping
}
self.literal_words = {"one", "ones"}
def process_words(self, words: List[str]) -> Iterator[str]:
prefix: Optional[str] = None
value: Optional[Union[str, int]] = None
skip = False
def to_fraction(s: str):
try:
return Fraction(s)
except ValueError:
return None
def output(result: Union[str, int]):
nonlocal prefix, value
result = str(result)
if prefix is not None:
result = prefix + result
value = None
prefix = None
return result
if len(words) == 0:
return
for i, current in enumerate(words):
prev = words[i - 1] if i != 0 else None
next = words[i + 1] if i != len(words) - 1 else None
if skip:
skip = False
continue
next_is_numeric = next is not None and re.match(r"^\d+(\.\d+)?$", next)
has_prefix = current[0] in self.prefixes
current_without_prefix = current[1:] if has_prefix else current
if re.match(r"^\d+(\.\d+)?$", current_without_prefix):
# arabic numbers (potentially with signs and fractions)
f = to_fraction(current_without_prefix)
if f is None:
raise ValueError("Converting the fraction failed")
if value is not None:
if isinstance(value, str) and value.endswith("."):
# concatenate decimals / ip address components
value = str(value) + str(current)
continue
else:
yield output(value)
prefix = current[0] if has_prefix else prefix
if f.denominator == 1:
value = f.numerator # store integers as int
else:
value = current_without_prefix
elif current not in self.words:
# non-numeric words
if value is not None:
yield output(value)
yield output(current)
elif current in self.zeros:
value = str(value or "") + "0"
elif current in self.ones:
ones = self.ones[current]
if value is None:
value = ones
elif isinstance(value, str) or prev in self.ones:
if prev in self.tens and ones < 10: # replace the last zero with the digit
value = value[:-1] + str(ones)
else:
value = str(value) + str(ones)
elif ones < 10:
if value % 10 == 0:
value += ones
else:
value = str(value) + str(ones)
else: # eleven to nineteen
if value % 100 == 0:
value += ones
else:
value = str(value) + str(ones)
elif current in self.ones_suffixed:
# ordinal or cardinal; yield the number right away
ones, suffix = self.ones_suffixed[current]
if value is None:
yield output(str(ones) + suffix)
elif isinstance(value, str) or prev in self.ones:
if prev in self.tens and ones < 10:
yield output(value[:-1] + str(ones) + suffix)
else:
yield output(str(value) + str(ones) + suffix)
elif ones < 10:
if value % 10 == 0:
yield output(str(value + ones) + suffix)
else:
yield output(str(value) + str(ones) + suffix)
else: # eleven to nineteen
if value % 100 == 0:
yield output(str(value + ones) + suffix)
else:
yield output(str(value) + str(ones) + suffix)
value = None
elif current in self.tens:
tens = self.tens[current]
if value is None:
value = tens
elif isinstance(value, str):
value = str(value) + str(tens)
else:
if value % 100 == 0:
value += tens
else:
value = str(value) + str(tens)
elif current in self.tens_suffixed:
# ordinal or cardinal; yield the number right away
tens, suffix = self.tens_suffixed[current]
if value is None:
yield output(str(tens) + suffix)
elif isinstance(value, str):
yield output(str(value) + str(tens) + suffix)
else:
if value % 100 == 0:
yield output(str(value + tens) + suffix)
else:
yield output(str(value) + str(tens) + suffix)
elif current in self.multipliers:
multiplier = self.multipliers[current]
if value is None:
value = multiplier
elif isinstance(value, str) or value == 0:
f = to_fraction(value)
p = f * multiplier if f is not None else None
if f is not None and p.denominator == 1:
value = p.numerator
else:
yield output(value)
value = multiplier
else:
before = value // 1000 * 1000
residual = value % 1000
value = before + residual * multiplier
elif current in self.multipliers_suffixed:
multiplier, suffix = self.multipliers_suffixed[current]
if value is None:
yield output(str(multiplier) + suffix)
elif isinstance(value, str):
f = to_fraction(value)
p = f * multiplier if f is not None else None
if f is not None and p.denominator == 1:
yield output(str(p.numerator) + suffix)
else:
yield output(value)
yield output(str(multiplier) + suffix)
else: # int
before = value // 1000 * 1000
residual = value % 1000
value = before + residual * multiplier
yield output(str(value) + suffix)
value = None
elif current in self.preceding_prefixers:
# apply prefix (positive, minus, etc.) if it precedes a number
if value is not None:
yield output(value)
if next in self.words or next_is_numeric:
prefix = self.preceding_prefixers[current]
else:
yield output(current)
elif current in self.following_prefixers:
# apply prefix (dollars, cents, etc.) only after a number
if value is not None:
prefix = self.following_prefixers[current]
yield output(value)
else:
yield output(current)
elif current in self.suffixers:
# apply suffix symbols (percent -> '%')
if value is not None:
suffix = self.suffixers[current]
if isinstance(suffix, dict):
if next in suffix:
yield output(str(value) + suffix[next])
skip = True
else:
yield output(value)
yield output(current)
else:
yield output(str(value) + suffix)
else:
yield output(current)
elif current in self.specials:
if next not in self.words and not next_is_numeric:
# apply special handling only if the next word can be numeric
if value is not None:
yield output(value)
yield output(current)
elif current == "and":
# ignore "and" after hundreds, thousands, etc.
if prev not in self.multipliers:
if value is not None:
yield output(value)
yield output(current)
elif current == "double" or current == "triple":
if next in self.ones or next in self.zeros:
repeats = 2 if current == "double" else 3
ones = self.ones.get(next, 0)
value = str(value or "") + str(ones) * repeats
skip = True
else:
if value is not None:
yield output(value)
yield output(current)
elif current == "point":
if next in self.decimals or next_is_numeric:
value = str(value or "") + "."
else:
# should all have been covered at this point
raise ValueError(f"Unexpected token: {current}")
else:
# all should have been covered at this point
raise ValueError(f"Unexpected token: {current}")
if value is not None:
yield output(value)
def preprocess(self, s: str):
# replace "<number> and a half" with "<number> point five"
results = []
segments = re.split(r"\band\s+a\s+half\b", s)
for i, segment in enumerate(segments):
if len(segment.strip()) == 0:
continue
if i == len(segments) - 1:
results.append(segment)
else:
results.append(segment)
last_word = segment.rsplit(maxsplit=2)[-1]
if last_word in self.decimals or last_word in self.multipliers:
results.append("point five")
else:
results.append("and a half")
s = " ".join(results)
# put a space at number/letter boundary
s = re.sub(r"([a-z])([0-9])", r"\1 \2", s)
s = re.sub(r"([0-9])([a-z])", r"\1 \2", s)
# but remove spaces which could be a suffix
s = re.sub(r"([0-9])\s+(st|nd|rd|th|s)\b", r"\1\2", s)
return s
def postprocess(self, s: str):
def combine_cents(m: Match):
try:
currency = m.group(1)
integer = m.group(2)
cents = int(m.group(3))
return f"{currency}{integer}.{cents:02d}"
except ValueError:
return m.string
def extract_cents(m: Match):
try:
return f"¢{int(m.group(1))}"
except ValueError:
return m.string
# apply currency postprocessing; "$2 and ¢7" -> "$2.07"
s = re.sub(r"([€£$])([0-9]+) (?:and )?¢([0-9]{1,2})\b", combine_cents, s)
s = re.sub(r"[€£$]0.([0-9]{1,2})\b", extract_cents, s)
# write "one(s)" instead of "1(s)", just for the readability
s = re.sub(r"\b1(s?)\b", r"one\1", s)
return s
def __call__(self, s: str):
s = self.preprocess(s)
s = " ".join(word for word in self.process_words(s.split()) if word is not None)
s = self.postprocess(s)
return s
class EnglishSpellingNormalizer:
"""
Applies British-American spelling mappings as listed in [1].
[1] https://www.tysto.com/uk-us-spelling-list.html
"""
def __init__(self, english_spelling_mapping):
self.mapping = english_spelling_mapping
def __call__(self, s: str):
return " ".join(self.mapping.get(word, word) for word in s.split())
class EnglishTextNormalizer:
def __init__(self, english_spelling_mapping):
self.ignore_patterns = r"\b(hmm|mm|mhm|mmm|uh|um)\b"
self.replacers = {
# common contractions
r"\bwon't\b": "will not",
r"\bcan't\b": "can not",
r"\blet's\b": "let us",
r"\bain't\b": "aint",
r"\by'all\b": "you all",
r"\bwanna\b": "want to",
r"\bgotta\b": "got to",
r"\bgonna\b": "going to",
r"\bi'ma\b": "i am going to",
r"\bimma\b": "i am going to",
r"\bwoulda\b": "would have",
r"\bcoulda\b": "could have",
r"\bshoulda\b": "should have",
r"\bma'am\b": "madam",
# contractions in titles/prefixes
r"\bmr\b": "mister ",
r"\bmrs\b": "missus ",
r"\bst\b": "saint ",
r"\bdr\b": "doctor ",
r"\bprof\b": "professor ",
r"\bcapt\b": "captain ",
r"\bgov\b": "governor ",
r"\bald\b": "alderman ",
r"\bgen\b": "general ",
r"\bsen\b": "senator ",
r"\brep\b": "representative ",
r"\bpres\b": "president ",
r"\brev\b": "reverend ",
r"\bhon\b": "honorable ",
r"\basst\b": "assistant ",
r"\bassoc\b": "associate ",
r"\blt\b": "lieutenant ",
r"\bcol\b": "colonel ",
r"\bjr\b": "junior ",
r"\bsr\b": "senior ",
r"\besq\b": "esquire ",
# prefect tenses, ideally it should be any past participles, but it's harder..
r"'d been\b": " had been",
r"'s been\b": " has been",
r"'d gone\b": " had gone",
r"'s gone\b": " has gone",
r"'d done\b": " had done", # "'s done" is ambiguous
r"'s got\b": " has got",
# general contractions
r"n't\b": " not",
r"'re\b": " are",
r"'s\b": " is",
r"'d\b": " would",
r"'ll\b": " will",
r"'t\b": " not",
r"'ve\b": " have",
r"'m\b": " am",
}
self.standardize_numbers = EnglishNumberNormalizer()
self.standardize_spellings = EnglishSpellingNormalizer(english_spelling_mapping)
def __call__(self, s: str):
s = s.lower()
s = re.sub(r"[<\[][^>\]]*[>\]]", "", s) # remove words between brackets
s = re.sub(r"\(([^)]+?)\)", "", s) # remove words between parenthesis
s = re.sub(self.ignore_patterns, "", s)
s = re.sub(r"\s+'", "'", s) # standardize when there's a space before an apostrophe
for pattern, replacement in self.replacers.items():
s = re.sub(pattern, replacement, s)
s = re.sub(r"(\d),(\d)", r"\1\2", s) # remove commas between digits
s = re.sub(r"\.([^0-9]|$)", r" \1", s) # remove periods not followed by numbers
s = remove_symbols_and_diacritics(s, keep=".%$¢€£") # keep some symbols for numerics
s = self.standardize_numbers(s)
s = self.standardize_spellings(s)
# now remove prefix/suffix symbols that are not preceded/followed by numbers
s = re.sub(r"[.$¢€£]([^0-9])", r" \1", s)
s = re.sub(r"([^0-9])%", r"\1 ", s)
s = re.sub(r"\s+", " ", s) # replace any successive whitespace characters with a space
return s