FunASR/fun_text_processing/text_normalization/zh/graph_utils.py

118 lines
3.3 KiB
Python

import os
import string
from pathlib import Path
from typing import Dict
import pynini
from pynini import Far
from pynini.export import export
from pynini.lib import byte, pynutil, utf8
FUN_CHAR = utf8.VALID_UTF8_CHAR
FUN_DIGIT = byte.DIGIT
FUN_LOWER = pynini.union(*string.ascii_lowercase).optimize()
FUN_UPPER = pynini.union(*string.ascii_uppercase).optimize()
FUN_ALPHA = pynini.union(FUN_LOWER, FUN_UPPER).optimize()
FUN_SPACE = " "
FUN_WHITE_SPACE = pynini.union(" ", "\t", "\n", "\r", "\u00A0").optimize()
FUN_NOT_SPACE = pynini.difference(FUN_CHAR, FUN_WHITE_SPACE).optimize()
FUN_NOT_QUOTE = pynini.difference(FUN_CHAR, r'"').optimize()
FUN_PUNCT = pynini.union(*map(pynini.escape, string.punctuation)).optimize()
FUN_SIGMA = pynini.closure(FUN_CHAR)
delete_space = pynutil.delete(pynini.closure(FUN_WHITE_SPACE))
delete_zero_or_one_space = pynutil.delete(pynini.closure(FUN_WHITE_SPACE, 0, 1))
insert_space = pynutil.insert(" ")
delete_extra_space = pynini.cross(pynini.closure(FUN_WHITE_SPACE, 1), " ")
def generator_main(file_name: str, graphs: Dict[str, "pynini.FstLike"]):
"""
Exports graph as OpenFst finite state archive (FAR) file with given file name and rule name.
Args:
file_name: exported file name
graphs: Mapping of a rule name and Pynini WFST graph to be exported
"""
exporter = export.Exporter(file_name)
for rule, graph in graphs.items():
exporter[rule] = graph.optimize()
exporter.close()
print(f"Created {file_name}")
class GraphFst:
"""
Base class for all grammar fsts.
Args:
name: name of grammar class
kind: either 'classify' or 'verbalize'
deterministic: if True will provide a single transduction option,
for False multiple transduction are generated (used for audio-based normalization)
"""
def __init__(self, name: str, kind: str, deterministic: bool = True):
self.name = name
self.kind = kind
self._fst = None
self.deterministic = deterministic
self.far_path = Path(os.path.dirname(__file__) + "/grammars/" + kind + "/" + name + ".far")
if self.far_exist():
self._fst = Far(
self.far_path, mode="r", arc_type="standard", far_type="default"
).get_fst()
def far_exist(self) -> bool:
"""
Returns true if FAR can be loaded
"""
return self.far_path.exists()
@property
def fst(self) -> "pynini.FstLike":
return self._fst
@fst.setter
def fst(self, fst):
self._fst = fst
def add_tokens(self, fst) -> "pynini.FstLike":
"""
Wraps class name around to given fst
Args:
fst: input fst
Returns:
Fst: fst
"""
return pynutil.insert(f"{self.name} {{ ") + fst + pynutil.insert(" }")
def delete_tokens(self, fst) -> "pynini.FstLike":
"""
Deletes class name wrap around output of given fst
Args:
fst: input fst
Returns:
Fst: fst
"""
res = (
pynutil.delete(f"{self.name}")
+ delete_space
+ pynutil.delete("{")
+ delete_space
+ fst
+ delete_space
+ pynutil.delete("}")
)
return res @ pynini.cdrewrite(pynini.cross("\u00A0", " "), "", "", FUN_SIGMA)