import pynini
|
from fun_text_processing.text_normalization.zh.graph_utils import (
|
FUN_ALPHA,
|
FUN_DIGIT,
|
FUN_PUNCT,
|
FUN_SIGMA,
|
FUN_WHITE_SPACE,
|
GraphFst,
|
)
|
from fun_text_processing.text_normalization.zh.utils import get_abs_path
|
from pynini.lib import pynutil, utf8
|
|
|
class PostProcessor(GraphFst):
|
"""
|
Postprocessing of TN, now contains:
|
1. punctuation removal
|
2. letter case conversion
|
3. oov tagger
|
"""
|
|
def __init__(
|
self,
|
remove_puncts: bool = False,
|
to_upper: bool = False,
|
to_lower: bool = False,
|
tag_oov: bool = False,
|
):
|
super().__init__(name="PostProcessor", kind="processor")
|
|
graph = pynini.cdrewrite("", "", "", FUN_SIGMA)
|
if remove_puncts:
|
remove_puncts_graph = pynutil.delete(
|
pynini.union(
|
FUN_PUNCT, pynini.string_file(get_abs_path("data/char/punctuations_zh.tsv"))
|
)
|
)
|
graph @= pynini.cdrewrite(remove_puncts_graph, "", "", FUN_SIGMA).optimize()
|
|
if to_upper or to_lower:
|
if to_upper:
|
conv_cases_graph = pynini.inverse(
|
pynini.string_file(get_abs_path("data/char/upper_to_lower.tsv"))
|
)
|
else:
|
conv_cases_graph = pynini.string_file(get_abs_path("data/char/upper_to_lower.tsv"))
|
|
graph @= pynini.cdrewrite(conv_cases_graph, "", "", FUN_SIGMA).optimize()
|
|
if tag_oov:
|
zh_charset_std = pynini.string_file(
|
get_abs_path("data/char/charset_national_standard_2013_8105.tsv")
|
)
|
zh_charset_ext = pynini.string_file(get_abs_path("data/char/charset_extension.tsv"))
|
|
zh_charset = (
|
zh_charset_std
|
| zh_charset_ext
|
| pynini.string_file(get_abs_path("data/char/punctuations_zh.tsv"))
|
)
|
en_charset = FUN_DIGIT | FUN_ALPHA | FUN_PUNCT | FUN_WHITE_SPACE
|
charset = zh_charset | en_charset
|
|
with open(get_abs_path("data/char/oov_tags.tsv"), "r") as f:
|
tags = f.readline().strip().split("\t")
|
assert len(tags) == 2
|
ltag, rtag = tags
|
|
oov_charset = pynini.difference(utf8.VALID_UTF8_CHAR, charset)
|
tag_oov_graph = pynutil.insert(ltag) + oov_charset + pynutil.insert(rtag)
|
graph @= pynini.cdrewrite(tag_oov_graph, "", "", FUN_SIGMA).optimize()
|
|
self.fst = graph.optimize()
|
