def __init__(self, cfg: DecoderConfig, tgt_dict: Dictionary) -> None:
self.tgt_dict = tgt_dict
self.vocab_size = len(tgt_dict)
self.nbest = cfg.nbest
self.unitlm = cfg.unitlm
if cfg.criterion == "ctc":
self.criterion_type = CriterionType.CTC
self.blank = (tgt_dict.index("<ctc_blank>") if "<ctc_blank>"
in tgt_dict.indices else tgt_dict.bos())
if "<sep>" in tgt_dict.indices:
self.silence = tgt_dict.index("<sep>")
elif "|" in tgt_dict.indices:
self.silence = tgt_dict.index("|")
else:
self.silence = tgt_dict.eos()
self.asgtransitions = None
elif cfg.criterion == "asg_loss":
self.criterion_type = CriterionType.ASG
self.blank = -1
self.silence = -1
self.asgtransitions = cfg.asgtransitions
self.maxreplabel = cfg.maxreplabel
assert len(self.asgtransitions) == self.vocab_size**2
else:
raise RuntimeError(f"unknown criterion: {cfg.criterion}")
def __init__(self,
args,
token_dictionary: Dictionary,
expansion_dictionary: Dictionary,
expansion_strategy: ExpansionStrategy,
device: Optional[Union[torch.device, str]] = None,
regenerate_tokens: bool = False,
temperature: float = 1.0):
self.temperature = temperature
self.inference = IterativeInference(token_dictionary,
expansion_dictionary,
expansion_strategy,
device,
mask_unk=True)
self.dependency_placeholder_ids = {
token_dictionary.index(t)
for t in expansion_strategy.get_dependency_placeholders()
}
def expand(e):
left_deps, right_deps = expansion_strategy.expand_deps(e)
left_dep_idxs = [token_dictionary.index(t) for t in left_deps]
right_dep_idxs = [token_dictionary.index(t) for t in right_deps]
return left_dep_idxs, right_dep_idxs
self.expansions = {
expansion_dictionary.index(e): expand(e)
for e in expansion_dictionary.symbols
}
self.regenerate_tokens = regenerate_tokens
def __init__(self, tgt_dict: Dictionary) -> None:
self.tgt_dict = tgt_dict
self.vocab_size = len(tgt_dict)
self.blank = (tgt_dict.index("<ctc_blank>")
if "<ctc_blank>" in tgt_dict.indices else tgt_dict.bos())
if "<sep>" in tgt_dict.indices:
self.silence = tgt_dict.index("<sep>")
elif "|" in tgt_dict.indices:
self.silence = tgt_dict.index("|")
else:
self.silence = tgt_dict.eos()
def __init__(self,
token_dictionary: Dictionary,
expansion_dictionary: Dictionary,
expansion_strategy: ExpansionStrategy,
device=None,
mask_unk: bool = True):
assert token_dictionary.pad_index == expansion_dictionary.pad_index
self.device = device or torch.device('cpu')
self.pad_idx = token_dictionary.pad_index
self.token_dictionary = token_dictionary
self.expansion_dictionary = expansion_dictionary
self.expansion_strategy = expansion_strategy
self.root_token_id = token_dictionary.index(expansion_strategy.root_node_token())
minus_inf = float('-inf')
# create mask to use in the token softmax later
token_prob_mask = np.zeros(shape=(len(token_dictionary)), dtype=np.float32)
for dep_placeholder in expansion_strategy.get_dependency_placeholders():
index_to_mask = token_dictionary.index(dep_placeholder)
if index_to_mask == token_dictionary.unk_index:
continue # symbol not found (e.g. [subword] if no subwords) ==> skip
token_prob_mask[index_to_mask] = minus_inf
special_token_idxs = [token_dictionary.pad_index, token_dictionary.eos_index]
if mask_unk:
special_token_idxs += [token_dictionary.unk_index]
for special_token_idx in special_token_idxs:
token_prob_mask[special_token_idx] = minus_inf
self.token_prob_mask = torch.from_numpy(token_prob_mask).to(device)
# create mask to use in the expansion softmax later
expansion_prob_mask = np.zeros(shape=(len(expansion_dictionary)), dtype=np.float32)
special_idxs = [expansion_dictionary.pad_index, expansion_dictionary.eos_index]
if mask_unk:
special_idxs = [expansion_dictionary.unk_index]
for special_idx in special_idxs:
expansion_prob_mask[special_idx] = minus_inf
self.expansion_prob_mask = torch.from_numpy(expansion_prob_mask).to(device)
def tok_ids(tokens: List[str], dictionary: Dictionary) -> List[int]:
return [dictionary.index(t) for t in tokens]
def __init__(self, cfg: DecoderConfig, tgt_dict: Dictionary) -> None:
super().__init__(cfg, tgt_dict)
self.lexicon = load_words(cfg.lexicon) if cfg.lexicon else None
self.idx_to_wrd = {}
checkpoint = torch.load(cfg.lmpath, map_location="cpu")
if "cfg" in checkpoint and checkpoint["cfg"] is not None:
lm_args = checkpoint["cfg"]
else:
lm_args = convert_namespace_to_omegaconf(checkpoint["args"])
with open_dict(lm_args.task):
lm_args.task.data = osp.dirname(cfg.lmpath)
task = tasks.setup_task(lm_args.task)
model = task.build_model(lm_args.model)
model.load_state_dict(checkpoint["model"], strict=False)
self.trie = Trie(self.vocab_size, self.silence)
self.word_dict = task.dictionary
self.unk_word = self.word_dict.unk()
self.lm = FairseqLM(self.word_dict, model)
if self.lexicon:
start_state = self.lm.start(False)
for i, (word, spellings) in enumerate(self.lexicon.items()):
if self.unitlm:
word_idx = i
self.idx_to_wrd[i] = word
score = 0
else:
word_idx = self.word_dict.index(word)
_, score = self.lm.score(start_state,
word_idx,
no_cache=True)
for spelling in spellings:
spelling_idxs = [
tgt_dict.index(token) for token in spelling
]
assert tgt_dict.unk() not in spelling_idxs, \
f"{spelling} {spelling_idxs}"
self.trie.insert(spelling_idxs, word_idx, score)
self.trie.smear(SmearingMode.MAX)
self.decoder_opts = LexiconDecoderOptions(
beam_size=cfg.beam,
beam_size_token=cfg.beamsizetoken or len(tgt_dict),
beam_threshold=cfg.beamthreshold,
lm_weight=cfg.lmweight,
word_score=cfg.wordscore,
unk_score=cfg.unkweight,
sil_score=cfg.silweight,
log_add=False,
criterion_type=self.criterion_type,
)
if self.asgtransitions is None:
self.asgtransitions = []
self.decoder = LexiconDecoder(
self.decoder_opts,
self.trie,
self.lm,
self.silence,
self.blank,
self.unk_word,
self.asgtransitions,
self.unitlm,
)
else:
assert self.unitlm, "Lexicon-free decoding requires unit LM"
d = {w: [[w]] for w in tgt_dict.symbols}
self.word_dict = create_word_dict(d)
self.lm = KenLM(cfg.lmpath, self.word_dict)
self.decoder_opts = LexiconFreeDecoderOptions(
beam_size=cfg.beam,
beam_size_token=cfg.beamsizetoken or len(tgt_dict),
beam_threshold=cfg.beamthreshold,
lm_weight=cfg.lmweight,
sil_score=cfg.silweight,
log_add=False,
criterion_type=self.criterion_type,
)
self.decoder = LexiconFreeDecoder(self.decoder_opts, self.lm,
self.silence, self.blank, [])
def __init__(self, cfg: DecoderConfig, tgt_dict: Dictionary) -> None:
super().__init__(cfg, tgt_dict)
if cfg.lexicon:
self.lexicon = load_words(cfg.lexicon)
self.word_dict = create_word_dict(self.lexicon)
self.unk_word = self.word_dict.get_index("<unk>")
self.lm = KenLM(cfg.lmpath, self.word_dict)
self.trie = Trie(self.vocab_size, self.silence)
start_state = self.lm.start(False)
for word, spellings in self.lexicon.items():
word_idx = self.word_dict.get_index(word)
_, score = self.lm.score(start_state, word_idx)
for spelling in spellings:
spelling_idxs = [
tgt_dict.index(token) for token in spelling
]
assert tgt_dict.unk() not in spelling_idxs, \
f"{spelling} {spelling_idxs}"
self.trie.insert(spelling_idxs, word_idx, score)
self.trie.smear(SmearingMode.MAX)
self.decoder_opts = LexiconDecoderOptions(
beam_size=cfg.beam,
beam_size_token=cfg.beamsizetoken or len(tgt_dict),
beam_threshold=cfg.beamthreshold,
lm_weight=cfg.lmweight,
word_score=cfg.wordscore,
unk_score=cfg.unkweight,
sil_score=cfg.silweight,
log_add=False,
criterion_type=self.criterion_type,
)
if self.asgtransitions is None:
self.asgtransitions = []
self.decoder = LexiconDecoder(
self.decoder_opts,
self.trie,
self.lm,
self.silence,
self.blank,
self.unk_word,
self.asgtransitions,
self.unitlm,
)
else:
assert self.unitlm, "Lexicon-free decoding requires unit LM"
d = {w: [[w]] for w in tgt_dict.symbols}
self.word_dict = create_word_dict(d)
self.lm = KenLM(cfg.lmpath, self.word_dict)
self.decoder_opts = LexiconFreeDecoderOptions(
beam_size=cfg.beam,
beam_size_token=cfg.beamsizetoken or len(tgt_dict),
beam_threshold=cfg.beamthreshold,
lm_weight=cfg.lmweight,
sil_score=cfg.silweight,
log_add=False,
criterion_type=self.criterion_type,
)
self.decoder = LexiconFreeDecoder(self.decoder_opts, self.lm,
self.silence, self.blank, [])
