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)
|
