mirrors/icefall
1
0
Fork 0
mirror of https://github.com/k2-fsa/icefall.git synced 2025-08-09 01:52:41 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add fast_beam_search_nbest. (#420)

Browse Source 
* Add fast_beam_search_nbest.

* Fix CI errors.

* Fix CI errors.

* More fixes.

* Small fixes.

* Support using log_add in LG decoding with fast_beam_search.

* Support LG decoding in pruned_transducer_stateless

* Support LG for pruned_transducer_stateless2.

* Support LG for fast beam search.

* Minor fixes.
This commit is contained in:
Fangjun Kuang 2022-06-22 00:09:25 +08:00 committed by GitHub
parent 7100c33820
commit dc89b61b80
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
10 changed files with 1298 additions and 194 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
.github/scripts/run-librispeech-pruned-transducer-stateless5-2022-05-13.sh vendored
View File

@ -32,6 +32,12 @@ for sym in 1 2 3; do
--max-sym-per-frame $sym \
--checkpoint $repo/exp/pretrained.pt \
--bpe-model $repo/data/lang_bpe_500/bpe.model \
--num-encoder-layers 18 \
--dim-feedforward 2048 \
--nhead 8 \
--encoder-dim 512 \
--decoder-dim 512 \
--joiner-dim 512
$repo/test_wavs/1089-134686-0001.wav \
$repo/test_wavs/1221-135766-0001.wav \
$repo/test_wavs/1221-135766-0002.wav

12
.github/workflows/test.yml vendored
View File

@ -33,13 +33,13 @@ jobs:
# disable macOS test for now.
os: [ubuntu-18.04]
python-version: [3.7, 3.8]
torch: ["1.8.0", "1.10.0"]
torchaudio: ["0.8.0", "0.10.0"]
k2-version: ["1.9.dev20211101"]
torch: ["1.8.0", "1.11.0"]
torchaudio: ["0.8.0", "0.11.0"]
k2-version: ["1.15.1.dev20220427"]
exclude:
- torch: "1.8.0"
torchaudio: "0.10.0"
- torch: "1.10.0"
torchaudio: "0.11.0"
- torch: "1.11.0"
torchaudio: "0.8.0"
fail-fast: false
@ -67,7 +67,7 @@ jobs:
# numpy 1.20.x does not support python 3.6
pip install numpy==1.19
pip install torch==${{ matrix.torch }}+cpu -f https://download.pytorch.org/whl/cpu/torch_stable.html
if [[ ${{ matrix.torchaudio }} == "0.10.0" ]]; then
if [[ ${{ matrix.torchaudio }} == "0.11.0" ]]; then
pip install torchaudio==${{ matrix.torchaudio }}+cpu -f https://download.pytorch.org/whl/cpu/torch_stable.html
else
pip install torchaudio==${{ matrix.torchaudio }}

196
egs/librispeech/ASR/pruned_transducer_stateless/beam_search.py
View File

@ -75,6 +75,202 @@ def fast_beam_search_one_best(
return hyps
def fast_beam_search_nbest_LG(
model: Transducer,
decoding_graph: k2.Fsa,
encoder_out: torch.Tensor,
encoder_out_lens: torch.Tensor,
beam: float,
max_states: int,
max_contexts: int,
num_paths: int,
nbest_scale: float = 0.5,
use_double_scores: bool = True,
) -> List[List[int]]:
"""It limits the maximum number of symbols per frame to 1.
The process to get the results is:
- (1) Use fast beam search to get a lattice
- (2) Select `num_paths` paths from the lattice using k2.random_paths()
- (3) Unique the selected paths
- (4) Intersect the selected paths with the lattice and compute the
shortest path from the intersection result
- (5) The path with the largest score is used as the decoding output.
Args:
model:
An instance of `Transducer`.
decoding_graph:
Decoding graph used for decoding, may be a TrivialGraph or a HLG.
encoder_out:
A tensor of shape (N, T, C) from the encoder.
encoder_out_lens:
A tensor of shape (N,) containing the number of frames in `encoder_out`
before padding.
beam:
Beam value, similar to the beam used in Kaldi..
max_states:
Max states per stream per frame.
max_contexts:
Max contexts pre stream per frame.
num_paths:
Number of paths to extract from the decoded lattice.
nbest_scale:
It's the scale applied to the lattice.scores. A smaller value
yields more unique paths.
use_double_scores:
True to use double precision for computation. False to use
single precision.
Returns:
Return the decoded result.
"""
lattice = fast_beam_search(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=beam,
max_states=max_states,
max_contexts=max_contexts,
)
nbest = Nbest.from_lattice(
lattice=lattice,
num_paths=num_paths,
use_double_scores=use_double_scores,
nbest_scale=nbest_scale,
)
# The following code is modified from nbest.intersect()
word_fsa = k2.invert(nbest.fsa)
if hasattr(lattice, "aux_labels"):
# delete token IDs as it is not needed
del word_fsa.aux_labels
word_fsa.scores.zero_()
word_fsa_with_epsilon_loops = k2.linear_fsa_with_self_loops(word_fsa)
path_to_utt_map = nbest.shape.row_ids(1)
if hasattr(lattice, "aux_labels"):
# lattice has token IDs as labels and word IDs as aux_labels.
# inv_lattice has word IDs as labels and token IDs as aux_labels
inv_lattice = k2.invert(lattice)
inv_lattice = k2.arc_sort(inv_lattice)
else:
inv_lattice = k2.arc_sort(lattice)
if inv_lattice.shape[0] == 1:
path_lattice = k2.intersect_device(
inv_lattice,
word_fsa_with_epsilon_loops,
b_to_a_map=torch.zeros_like(path_to_utt_map),
sorted_match_a=True,
)
else:
path_lattice = k2.intersect_device(
inv_lattice,
word_fsa_with_epsilon_loops,
b_to_a_map=path_to_utt_map,
sorted_match_a=True,
)
# path_lattice has word IDs as labels and token IDs as aux_labels
path_lattice = k2.top_sort(k2.connect(path_lattice))
tot_scores = path_lattice.get_tot_scores(
use_double_scores=use_double_scores,
log_semiring=True, # Note: we always use True
)
# See https://github.com/k2-fsa/icefall/pull/420 for why
# we always use log_semiring=True
ragged_tot_scores = k2.RaggedTensor(nbest.shape, tot_scores)
best_hyp_indexes = ragged_tot_scores.argmax()
best_path = k2.index_fsa(nbest.fsa, best_hyp_indexes)
hyps = get_texts(best_path)
return hyps
def fast_beam_search_nbest(
model: Transducer,
decoding_graph: k2.Fsa,
encoder_out: torch.Tensor,
encoder_out_lens: torch.Tensor,
beam: float,
max_states: int,
max_contexts: int,
num_paths: int,
nbest_scale: float = 0.5,
use_double_scores: bool = True,
) -> List[List[int]]:
"""It limits the maximum number of symbols per frame to 1.
The process to get the results is:
- (1) Use fast beam search to get a lattice
- (2) Select `num_paths` paths from the lattice using k2.random_paths()
- (3) Unique the selected paths
- (4) Intersect the selected paths with the lattice and compute the
shortest path from the intersection result
- (5) The path with the largest score is used as the decoding output.
Args:
model:
An instance of `Transducer`.
decoding_graph:
Decoding graph used for decoding, may be a TrivialGraph or a HLG.
encoder_out:
A tensor of shape (N, T, C) from the encoder.
encoder_out_lens:
A tensor of shape (N,) containing the number of frames in `encoder_out`
before padding.
beam:
Beam value, similar to the beam used in Kaldi..
max_states:
Max states per stream per frame.
max_contexts:
Max contexts pre stream per frame.
num_paths:
Number of paths to extract from the decoded lattice.
nbest_scale:
It's the scale applied to the lattice.scores. A smaller value
yields more unique paths.
use_double_scores:
True to use double precision for computation. False to use
single precision.
Returns:
Return the decoded result.
"""
lattice = fast_beam_search(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=beam,
max_states=max_states,
max_contexts=max_contexts,
)
nbest = Nbest.from_lattice(
lattice=lattice,
num_paths=num_paths,
use_double_scores=use_double_scores,
nbest_scale=nbest_scale,
)
# at this point, nbest.fsa.scores are all zeros.
nbest = nbest.intersect(lattice)
# Now nbest.fsa.scores contains acoustic scores
max_indexes = nbest.tot_scores().argmax()
best_path = k2.index_fsa(nbest.fsa, max_indexes)
hyps = get_texts(best_path)
return hyps
def fast_beam_search_nbest_oracle(
model: Transducer,
decoding_graph: k2.Fsa,

204
egs/librispeech/ASR/pruned_transducer_stateless/decode.py
View File

@ -50,20 +50,44 @@ Usage:
--exp-dir ./pruned_transducer_stateless/exp \
--max-duration 600 \
--decoding-method fast_beam_search \
--beam 4 \
--max-contexts 4 \
--max-states 8
--beam 20.0 \
--max-contexts 8 \
--max-states 64
(5) fast beam search using LG
(5) fast beam search (nbest)
./pruned_transducer_stateless/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless/exp \
--use-LG True \
--use-max False \
--max-duration 600 \
--decoding-method fast_beam_search \
--beam 8 \
--decoding-method fast_beam_search_nbest \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(6) fast beam search (nbest oracle WER)
./pruned_transducer_stateless/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_oracle \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(7) fast beam search (with LG)
./pruned_transducer_stateless/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_LG \
--beam 20.0 \
--max-contexts 8 \
--max-states 64
"""
@ -82,6 +106,9 @@ import torch.nn as nn
from asr_datamodule import LibriSpeechAsrDataModule
from beam_search import (
beam_search,
fast_beam_search_nbest,
fast_beam_search_nbest_LG,
fast_beam_search_nbest_oracle,
fast_beam_search_one_best,
greedy_search,
greedy_search_batch,
@ -99,7 +126,6 @@ from icefall.utils import (
AttributeDict,
setup_logger,
store_transcripts,
str2bool,
write_error_stats,
)
@ -153,7 +179,7 @@ def get_parser():
parser.add_argument(
"--lang-dir",
type=str,
type=Path,
default="data/lang_bpe_500",
help="The lang dir containing word table and LG graph",
)
@ -167,6 +193,11 @@ def get_parser():
- beam_search
- modified_beam_search
- fast_beam_search
- fast_beam_search_nbest
- fast_beam_search_nbest_oracle
- fast_beam_search_nbest_LG
If you use fast_beam_search_nbest_LG, you have to specify
`--lang-dir`, which should contain `LG.pt`.
""",
)
@ -182,30 +213,13 @@ def get_parser():
parser.add_argument(
"--beam",
type=float,
default=4,
default=20.0,
help="""A floating point value to calculate the cutoff score during beam
search (i.e., `cutoff = max-score - beam`), which is the same as the
`beam` in Kaldi.
Used only when --decoding-method is fast_beam_search""",
)
parser.add_argument(
"--use-LG",
type=str2bool,
default=False,
help="""Whether to use an LG graph for FSA-based beam search.
Used only when --decoding_method is fast_beam_search. If setting true,
it assumes there is an LG.pt file in lang_dir.""",
)
parser.add_argument(
"--use-max",
type=str2bool,
default=False,
help="""If True, use max-op to select the hypothesis that have the
max log_prob in case of duplicate hypotheses.
If False, use log_add.
Used only for beam_search, modified_beam_search, and fast_beam_search
Used only when --decoding-method is fast_beam_search,
fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle
""",
)
@ -214,7 +228,7 @@ def get_parser():
type=float,
default=0.01,
help="""
Used only when --decoding_method is fast_beam_search.
Used only when --decoding_method is fast_beam_search_nbest_LG.
It specifies the scale for n-gram LM scores.
""",
)
@ -222,9 +236,10 @@ def get_parser():
parser.add_argument(
"--max-contexts",
type=int,
default=4,
default=8,
help="""Used only when --decoding-method is
fast_beam_search""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
@ -232,7 +247,8 @@ def get_parser():
type=int,
default=8,
help="""Used only when --decoding-method is
fast_beam_search""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
@ -250,6 +266,24 @@ def get_parser():
Used only when --decoding_method is greedy_search""",
)
parser.add_argument(
"--num-paths",
type=int,
default=200,
help="""Number of paths for nbest decoding.
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
"--nbest-scale",
type=float,
default=0.5,
help="""Scale applied to lattice scores when computing nbest paths.
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
return parser
@ -286,7 +320,8 @@ def decode_one_batch(
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is fast_beam_search.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return the decoding result. See above description for the format of
the returned dict.
@ -299,6 +334,7 @@ def decode_one_batch(
# at entry, feature is (N, T, C)
supervisions = batch["supervisions"]
feature_lens = supervisions["num_frames"].to(device)
encoder_out, encoder_out_lens = model.encoder(
@ -316,12 +352,51 @@ def decode_one_batch(
max_contexts=params.max_contexts,
max_states=params.max_states,
)
if params.use_LG:
for hyp in hyp_tokens:
hyps.append([word_table[i] for i in hyp])
else:
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_LG":
hyp_tokens = fast_beam_search_nbest_LG(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in hyp_tokens:
hyps.append([word_table[i] for i in hyp])
elif params.decoding_method == "fast_beam_search_nbest":
hyp_tokens = fast_beam_search_nbest(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_oracle":
hyp_tokens = fast_beam_search_nbest_oracle(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
ref_texts=sp.encode(supervisions["text"]),
nbest_scale=params.nbest_scale,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif (
params.decoding_method == "greedy_search"
and params.max_sym_per_frame == 1
@ -339,7 +414,6 @@ def decode_one_batch(
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam_size,
use_max=params.use_max,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
@ -361,7 +435,6 @@ def decode_one_batch(
model=model,
encoder_out=encoder_out_i,
beam=params.beam_size,
use_max=params.use_max,
)
else:
raise ValueError(
@ -371,14 +444,17 @@ def decode_one_batch(
if params.decoding_method == "greedy_search":
return {"greedy_search": hyps}
elif params.decoding_method == "fast_beam_search":
return {
(
f"beam_{params.beam}_"
f"max_contexts_{params.max_contexts}_"
f"max_states_{params.max_states}"
): hyps
}
elif "fast_beam_search" in params.decoding_method:
key = f"beam_{params.beam}_"
key += f"max_contexts_{params.max_contexts}_"
key += f"max_states_{params.max_states}"
if "nbest" in params.decoding_method:
key += f"_num_paths_{params.num_paths}_"
key += f"nbest_scale_{params.nbest_scale}"
if "LG" in params.decoding_method:
key += f"_ngram_lm_scale_{params.ngram_lm_scale}"
return {key: hyps}
else:
return {f"beam_size_{params.beam_size}": hyps}
@ -406,7 +482,8 @@ def decode_dataset(
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is fast_beam_search.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return a dict, whose key may be "greedy_search" if greedy search
is used, or it may be "beam_7" if beam size of 7 is used.
@ -424,7 +501,7 @@ def decode_dataset(
if params.decoding_method == "greedy_search":
log_interval = 50
else:
log_interval = 10
log_interval = 20
results = defaultdict(list)
for batch_idx, batch in enumerate(dl):
@ -517,6 +594,9 @@ def main():
"greedy_search",
"beam_search",
"fast_beam_search",
"fast_beam_search_nbest",
"fast_beam_search_nbest_LG",
"fast_beam_search_nbest_oracle",
"modified_beam_search",
)
params.res_dir = params.exp_dir / params.decoding_method
@ -527,16 +607,18 @@ def main():
params.suffix = f"epoch-{params.epoch}-avg-{params.avg}"
if "fast_beam_search" in params.decoding_method:
params.suffix += f"-use-LG-{params.use_LG}"
params.suffix += f"-beam-{params.beam}"
params.suffix += f"-max-contexts-{params.max_contexts}"
params.suffix += f"-max-states-{params.max_states}"
params.suffix += f"-use-max-{params.use_max}"
if "nbest" in params.decoding_method:
params.suffix += f"-nbest-scale-{params.nbest_scale}"
params.suffix += f"-num-paths-{params.num_paths}"
if "LG" in params.decoding_method:
params.suffix += f"-ngram-lm-scale-{params.ngram_lm_scale}"
elif "beam_search" in params.decoding_method:
params.suffix += (
f"-{params.decoding_method}-beam-size-{params.beam_size}"
)
params.suffix += f"-use-max-{params.use_max}"
else:
params.suffix += f"-context-{params.context_size}"
params.suffix += f"-max-sym-per-frame-{params.max_sym_per_frame}"
@ -596,12 +678,14 @@ def main():
model.eval()
model.device = device
if params.decoding_method == "fast_beam_search":
if params.use_LG:
if "fast_beam_search" in params.decoding_method:
if params.decoding_method == "fast_beam_search_nbest_LG":
lexicon = Lexicon(params.lang_dir)
word_table = lexicon.word_table
lg_filename = params.lang_dir / "LG.pt"
logging.info(f"Loading {lg_filename}")
decoding_graph = k2.Fsa.from_dict(
torch.load(f"{params.lang_dir}/LG.pt", map_location=device)
torch.load(lg_filename, map_location=device)
)
decoding_graph.scores *= params.ngram_lm_scale
else:

200
egs/librispeech/ASR/pruned_transducer_stateless2/beam_search.py
View File

@ -37,7 +37,7 @@ def fast_beam_search_one_best(
) -> List[List[int]]:
"""It limits the maximum number of symbols per frame to 1.
A lattice is first obtained using modified beam search, and then
A lattice is first obtained using fast beam search, and then
the shortest path within the lattice is used as the final output.
Args:
@ -74,6 +74,202 @@ def fast_beam_search_one_best(
return hyps
def fast_beam_search_nbest_LG(
model: Transducer,
decoding_graph: k2.Fsa,
encoder_out: torch.Tensor,
encoder_out_lens: torch.Tensor,
beam: float,
max_states: int,
max_contexts: int,
num_paths: int,
nbest_scale: float = 0.5,
use_double_scores: bool = True,
) -> List[List[int]]:
"""It limits the maximum number of symbols per frame to 1.
The process to get the results is:
- (1) Use fast beam search to get a lattice
- (2) Select `num_paths` paths from the lattice using k2.random_paths()
- (3) Unique the selected paths
- (4) Intersect the selected paths with the lattice and compute the
shortest path from the intersection result
- (5) The path with the largest score is used as the decoding output.
Args:
model:
An instance of `Transducer`.
decoding_graph:
Decoding graph used for decoding, may be a TrivialGraph or a HLG.
encoder_out:
A tensor of shape (N, T, C) from the encoder.
encoder_out_lens:
A tensor of shape (N,) containing the number of frames in `encoder_out`
before padding.
beam:
Beam value, similar to the beam used in Kaldi..
max_states:
Max states per stream per frame.
max_contexts:
Max contexts pre stream per frame.
num_paths:
Number of paths to extract from the decoded lattice.
nbest_scale:
It's the scale applied to the lattice.scores. A smaller value
yields more unique paths.
use_double_scores:
True to use double precision for computation. False to use
single precision.
Returns:
Return the decoded result.
"""
lattice = fast_beam_search(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=beam,
max_states=max_states,
max_contexts=max_contexts,
)
nbest = Nbest.from_lattice(
lattice=lattice,
num_paths=num_paths,
use_double_scores=use_double_scores,
nbest_scale=nbest_scale,
)
# The following code is modified from nbest.intersect()
word_fsa = k2.invert(nbest.fsa)
if hasattr(lattice, "aux_labels"):
# delete token IDs as it is not needed
del word_fsa.aux_labels
word_fsa.scores.zero_()
word_fsa_with_epsilon_loops = k2.linear_fsa_with_self_loops(word_fsa)
path_to_utt_map = nbest.shape.row_ids(1)
if hasattr(lattice, "aux_labels"):
# lattice has token IDs as labels and word IDs as aux_labels.
# inv_lattice has word IDs as labels and token IDs as aux_labels
inv_lattice = k2.invert(lattice)
inv_lattice = k2.arc_sort(inv_lattice)
else:
inv_lattice = k2.arc_sort(lattice)
if inv_lattice.shape[0] == 1:
path_lattice = k2.intersect_device(
inv_lattice,
word_fsa_with_epsilon_loops,
b_to_a_map=torch.zeros_like(path_to_utt_map),
sorted_match_a=True,
)
else:
path_lattice = k2.intersect_device(
inv_lattice,
word_fsa_with_epsilon_loops,
b_to_a_map=path_to_utt_map,
sorted_match_a=True,
)
# path_lattice has word IDs as labels and token IDs as aux_labels
path_lattice = k2.top_sort(k2.connect(path_lattice))
tot_scores = path_lattice.get_tot_scores(
use_double_scores=use_double_scores,
log_semiring=True, # Note: we always use True
)
# See https://github.com/k2-fsa/icefall/pull/420 for why
# we always use log_semiring=True
ragged_tot_scores = k2.RaggedTensor(nbest.shape, tot_scores)
best_hyp_indexes = ragged_tot_scores.argmax()
best_path = k2.index_fsa(nbest.fsa, best_hyp_indexes)
hyps = get_texts(best_path)
return hyps
def fast_beam_search_nbest(
model: Transducer,
decoding_graph: k2.Fsa,
encoder_out: torch.Tensor,
encoder_out_lens: torch.Tensor,
beam: float,
max_states: int,
max_contexts: int,
num_paths: int,
nbest_scale: float = 0.5,
use_double_scores: bool = True,
) -> List[List[int]]:
"""It limits the maximum number of symbols per frame to 1.
The process to get the results is:
- (1) Use fast beam search to get a lattice
- (2) Select `num_paths` paths from the lattice using k2.random_paths()
- (3) Unique the selected paths
- (4) Intersect the selected paths with the lattice and compute the
shortest path from the intersection result
- (5) The path with the largest score is used as the decoding output.
Args:
model:
An instance of `Transducer`.
decoding_graph:
Decoding graph used for decoding, may be a TrivialGraph or a HLG.
encoder_out:
A tensor of shape (N, T, C) from the encoder.
encoder_out_lens:
A tensor of shape (N,) containing the number of frames in `encoder_out`
before padding.
beam:
Beam value, similar to the beam used in Kaldi..
max_states:
Max states per stream per frame.
max_contexts:
Max contexts pre stream per frame.
num_paths:
Number of paths to extract from the decoded lattice.
nbest_scale:
It's the scale applied to the lattice.scores. A smaller value
yields more unique paths.
use_double_scores:
True to use double precision for computation. False to use
single precision.
Returns:
Return the decoded result.
"""
lattice = fast_beam_search(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=beam,
max_states=max_states,
max_contexts=max_contexts,
)
nbest = Nbest.from_lattice(
lattice=lattice,
num_paths=num_paths,
use_double_scores=use_double_scores,
nbest_scale=nbest_scale,
)
# at this point, nbest.fsa.scores are all zeros.
nbest = nbest.intersect(lattice)
# Now nbest.fsa.scores contains acoustic scores
max_indexes = nbest.tot_scores().argmax()
best_path = k2.index_fsa(nbest.fsa, max_indexes)
hyps = get_texts(best_path)
return hyps
def fast_beam_search_nbest_oracle(
model: Transducer,
decoding_graph: k2.Fsa,
@ -89,7 +285,7 @@ def fast_beam_search_nbest_oracle(
) -> List[List[int]]:
"""It limits the maximum number of symbols per frame to 1.
A lattice is first obtained using modified beam search, and then
A lattice is first obtained using fast beam search, and then
we select `num_paths` linear paths from the lattice. The path
that has the minimum edit distance with the given reference transcript
is used as the output.

202
egs/librispeech/ASR/pruned_transducer_stateless2/decode.py
View File

@ -43,16 +43,53 @@ Usage:
--decoding-method modified_beam_search \
--beam-size 4
(4) fast beam search
(4) fast beam search (one best)
./pruned_transducer_stateless2/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless2/exp \
--max-duration 600 \
--decoding-method fast_beam_search \
--beam 4 \
--max-contexts 4 \
--max-states 8
--beam 20.0 \
--max-contexts 8 \
--max-states 64
(5) fast beam search (nbest)
./pruned_transducer_stateless2/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless2/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(6) fast beam search (nbest oracle WER)
./pruned_transducer_stateless2/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless2/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_oracle \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(7) fast beam search (with LG)
./pruned_transducer_stateless2/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless2/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_LG \
--beam 20.0 \
--max-contexts 8 \
--max-states 64
"""
@ -69,6 +106,9 @@ import torch.nn as nn
from asr_datamodule import LibriSpeechAsrDataModule
from beam_search import (
beam_search,
fast_beam_search_nbest,
fast_beam_search_nbest_LG,
fast_beam_search_nbest_oracle,
fast_beam_search_one_best,
greedy_search,
greedy_search_batch,
@ -81,6 +121,7 @@ from icefall.checkpoint import (
find_checkpoints,
load_checkpoint,
)
from icefall.lexicon import Lexicon
from icefall.utils import (
AttributeDict,
setup_logger,
@ -136,6 +177,13 @@ def get_parser():
help="Path to the BPE model",
)
parser.add_argument(
"--lang-dir",
type=Path,
default="data/lang_bpe_500",
help="The lang dir containing word table and LG graph",
)
parser.add_argument(
"--decoding-method",
type=str,
@ -145,6 +193,11 @@ def get_parser():
- beam_search
- modified_beam_search
- fast_beam_search
- fast_beam_search_nbest
- fast_beam_search_nbest_oracle
- fast_beam_search_nbest_LG
If you use fast_beam_search_nbest_LG, you have to specify
`--lang-dir`, which should contain `LG.pt`.
""",
)
@ -160,27 +213,42 @@ def get_parser():
parser.add_argument(
"--beam",
type=float,
default=4,
default=20.0,
help="""A floating point value to calculate the cutoff score during beam
search (i.e., `cutoff = max-score - beam`), which is the same as the
`beam` in Kaldi.
Used only when --decoding-method is fast_beam_search""",
Used only when --decoding-method is fast_beam_search,
fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle
""",
)
parser.add_argument(
"--ngram-lm-scale",
type=float,
default=0.01,
help="""
Used only when --decoding_method is fast_beam_search_nbest_LG.
It specifies the scale for n-gram LM scores.
""",
)
parser.add_argument(
"--max-contexts",
type=int,
default=4,
default=8,
help="""Used only when --decoding-method is
fast_beam_search""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
"--max-states",
type=int,
default=8,
default=64,
help="""Used only when --decoding-method is
fast_beam_search""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
@ -198,6 +266,24 @@ def get_parser():
Used only when --decoding_method is greedy_search""",
)
parser.add_argument(
"--num-paths",
type=int,
default=200,
help="""Number of paths for nbest decoding.
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
"--nbest-scale",
type=float,
default=0.5,
help="""Scale applied to lattice scores when computing nbest paths.
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
return parser
@ -206,6 +292,7 @@ def decode_one_batch(
model: nn.Module,
sp: spm.SentencePieceProcessor,
batch: dict,
word_table: Optional[k2.SymbolTable] = None,
decoding_graph: Optional[k2.Fsa] = None,
) -> Dict[str, List[List[str]]]:
"""Decode one batch and return the result in a dict. The dict has the
@ -229,9 +316,12 @@ def decode_one_batch(
It is the return value from iterating
`lhotse.dataset.K2SpeechRecognitionDataset`. See its documentation
for the format of the `batch`.
word_table:
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is fast_beam_search.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return the decoding result. See above description for the format of
the returned dict.
@ -263,6 +353,49 @@ def decode_one_batch(
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_LG":
hyp_tokens = fast_beam_search_nbest_LG(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in hyp_tokens:
hyps.append([word_table[i] for i in hyp])
elif params.decoding_method == "fast_beam_search_nbest":
hyp_tokens = fast_beam_search_nbest(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_oracle":
hyp_tokens = fast_beam_search_nbest_oracle(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
ref_texts=sp.encode(supervisions["text"]),
nbest_scale=params.nbest_scale,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif (
params.decoding_method == "greedy_search"
and params.max_sym_per_frame == 1
@ -318,6 +451,17 @@ def decode_one_batch(
f"max_states_{params.max_states}"
): hyps
}
elif "fast_beam_search" in params.decoding_method:
key = f"beam_{params.beam}_"
key += f"max_contexts_{params.max_contexts}_"
key += f"max_states_{params.max_states}"
if "nbest" in params.decoding_method:
key += f"_num_paths_{params.num_paths}_"
key += f"nbest_scale_{params.nbest_scale}"
if "LG" in params.decoding_method:
key += f"_ngram_lm_scale_{params.ngram_lm_scale}"
return {key: hyps}
else:
return {f"beam_size_{params.beam_size}": hyps}
@ -327,6 +471,7 @@ def decode_dataset(
params: AttributeDict,
model: nn.Module,
sp: spm.SentencePieceProcessor,
word_table: Optional[k2.SymbolTable] = None,
decoding_graph: Optional[k2.Fsa] = None,
) -> Dict[str, List[Tuple[List[str], List[str]]]]:
"""Decode dataset.
@ -340,9 +485,12 @@ def decode_dataset(
The neural model.
sp:
The BPE model.
word_table:
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is fast_beam_search.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return a dict, whose key may be "greedy_search" if greedy search
is used, or it may be "beam_7" if beam size of 7 is used.
@ -360,7 +508,7 @@ def decode_dataset(
if params.decoding_method == "greedy_search":
log_interval = 50
else:
log_interval = 10
log_interval = 20
results = defaultdict(list)
for batch_idx, batch in enumerate(dl):
@ -370,6 +518,7 @@ def decode_dataset(
params=params,
model=model,
sp=sp,
word_table=word_table,
decoding_graph=decoding_graph,
batch=batch,
)
@ -452,6 +601,9 @@ def main():
"greedy_search",
"beam_search",
"fast_beam_search",
"fast_beam_search_nbest",
"fast_beam_search_nbest_LG",
"fast_beam_search_nbest_oracle",
"modified_beam_search",
)
params.res_dir = params.exp_dir / params.decoding_method
@ -465,6 +617,11 @@ def main():
params.suffix += f"-beam-{params.beam}"
params.suffix += f"-max-contexts-{params.max_contexts}"
params.suffix += f"-max-states-{params.max_states}"
if "nbest" in params.decoding_method:
params.suffix += f"-nbest-scale-{params.nbest_scale}"
params.suffix += f"-num-paths-{params.num_paths}"
if "LG" in params.decoding_method:
params.suffix += f"-ngram-lm-scale-{params.ngram_lm_scale}"
elif "beam_search" in params.decoding_method:
params.suffix += (
f"-{params.decoding_method}-beam-size-{params.beam_size}"
@ -528,10 +685,24 @@ def main():
model.eval()
model.device = device
if params.decoding_method == "fast_beam_search":
decoding_graph = k2.trivial_graph(params.vocab_size - 1, device=device)
if "fast_beam_search" in params.decoding_method:
if params.decoding_method == "fast_beam_search_nbest_LG":
lexicon = Lexicon(params.lang_dir)
word_table = lexicon.word_table
lg_filename = params.lang_dir / "LG.pt"
logging.info(f"Loading {lg_filename}")
decoding_graph = k2.Fsa.from_dict(
torch.load(lg_filename, map_location=device)
)
decoding_graph.scores *= params.ngram_lm_scale
else:
word_table = None
decoding_graph = k2.trivial_graph(
params.vocab_size - 1, device=device
)
else:
decoding_graph = None
word_table = None
num_param = sum([p.numel() for p in model.parameters()])
logging.info(f"Number of model parameters: {num_param}")
@ -553,6 +724,7 @@ def main():
params=params,
model=model,
sp=sp,
word_table=word_table,
decoding_graph=decoding_graph,
)

246
egs/librispeech/ASR/pruned_transducer_stateless3/decode.py
View File

@ -19,40 +19,77 @@
Usage:
(1) greedy search
./pruned_transducer_stateless3/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method greedy_search
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method greedy_search
(2) beam search (not recommended)
./pruned_transducer_stateless3/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method beam_search \
--beam-size 4
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method beam_search \
--beam-size 4
(3) modified beam search
./pruned_transducer_stateless3/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method modified_beam_search \
--beam-size 4
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method modified_beam_search \
--beam-size 4
(4) fast beam search
(4) fast beam search (one best)
./pruned_transducer_stateless3/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method fast_beam_search \
--beam 4 \
--max-contexts 4 \
--max-states 8
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method fast_beam_search \
--beam 20.0 \
--max-contexts 8 \
--max-states 64
(5) fast beam search (nbest)
./pruned_transducer_stateless3/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(6) fast beam search (nbest oracle WER)
./pruned_transducer_stateless3/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_oracle \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(7) fast beam search (with LG)
./pruned_transducer_stateless3/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_LG \
--beam 20.0 \
--max-contexts 8 \
--max-states 64
"""
@ -69,6 +106,8 @@ import torch.nn as nn
from asr_datamodule import AsrDataModule
from beam_search import (
beam_search,
fast_beam_search_nbest,
fast_beam_search_nbest_LG,
fast_beam_search_nbest_oracle,
fast_beam_search_one_best,
greedy_search,
@ -83,6 +122,7 @@ from icefall.checkpoint import (
find_checkpoints,
load_checkpoint,
)
from icefall.lexicon import Lexicon
from icefall.utils import (
AttributeDict,
setup_logger,
@ -138,6 +178,13 @@ def get_parser():
help="Path to the BPE model",
)
parser.add_argument(
"--lang-dir",
type=Path,
default="data/lang_bpe_500",
help="The lang dir containing word table and LG graph",
)
parser.add_argument(
"--decoding-method",
type=str,
@ -147,7 +194,11 @@ def get_parser():
- beam_search
- modified_beam_search
- fast_beam_search
- fast_beam_search_nbest
- fast_beam_search_nbest_oracle
- fast_beam_search_nbest_LG
If you use fast_beam_search_nbest_LG, you have to specify
`--lang-dir`, which should contain `LG.pt`.
""",
)
@ -163,28 +214,42 @@ def get_parser():
parser.add_argument(
"--beam",
type=float,
default=4,
default=20.0,
help="""A floating point value to calculate the cutoff score during beam
search (i.e., `cutoff = max-score - beam`), which is the same as the
`beam` in Kaldi.
Used only when --decoding-method is
fast_beam_search or fast_beam_search_nbest_oracle""",
Used only when --decoding-method is fast_beam_search,
fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle
""",
)
parser.add_argument(
"--ngram-lm-scale",
type=float,
default=0.01,
help="""
Used only when --decoding_method is fast_beam_search_nbest_LG.
It specifies the scale for n-gram LM scores.
""",
)
parser.add_argument(
"--max-contexts",
type=int,
default=4,
default=8,
help="""Used only when --decoding-method is
fast_beam_search or fast_beam_search_nbest_oracle""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
"--max-states",
type=int,
default=8,
default=64,
help="""Used only when --decoding-method is
fast_beam_search or fast_beam_search_nbest_oracle""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
@ -205,10 +270,10 @@ def get_parser():
parser.add_argument(
"--num-paths",
type=int,
default=100,
help="""Number of paths for computed nbest oracle WER
when the decoding method is fast_beam_search_nbest_oracle.
""",
default=200,
help="""Number of paths for nbest decoding.
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
@ -216,9 +281,10 @@ def get_parser():
type=float,
default=0.5,
help="""Scale applied to lattice scores when computing nbest paths.
Used only when the decoding_method is fast_beam_search_nbest_oracle.
""",
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
return parser
@ -227,6 +293,7 @@ def decode_one_batch(
model: nn.Module,
sp: spm.SentencePieceProcessor,
batch: dict,
word_table: Optional[k2.SymbolTable] = None,
decoding_graph: Optional[k2.Fsa] = None,
) -> Dict[str, List[List[str]]]:
"""Decode one batch and return the result in a dict. The dict has the
@ -250,10 +317,12 @@ def decode_one_batch(
It is the return value from iterating
`lhotse.dataset.K2SpeechRecognitionDataset`. See its documentation
for the format of the `batch`.
word_table:
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is
fast_beam_search or fast_beam_search_nbest_oracle.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return the decoding result. See above description for the format of
the returned dict.
@ -285,6 +354,34 @@ def decode_one_batch(
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_LG":
hyp_tokens = fast_beam_search_nbest_LG(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in hyp_tokens:
hyps.append([word_table[i] for i in hyp])
elif params.decoding_method == "fast_beam_search_nbest":
hyp_tokens = fast_beam_search_nbest(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_oracle":
hyp_tokens = fast_beam_search_nbest_oracle(
model=model,
@ -355,16 +452,25 @@ def decode_one_batch(
f"max_states_{params.max_states}"
): hyps
}
elif params.decoding_method == "fast_beam_search_nbest_oracle":
elif params.decoding_method == "fast_beam_search":
return {
(
f"beam_{params.beam}_"
f"max_contexts_{params.max_contexts}_"
f"max_states_{params.max_states}_"
f"num_paths_{params.num_paths}_"
f"nbest_scale_{params.nbest_scale}"
f"max_states_{params.max_states}"
): hyps
}
elif "fast_beam_search" in params.decoding_method:
key = f"beam_{params.beam}_"
key += f"max_contexts_{params.max_contexts}_"
key += f"max_states_{params.max_states}"
if "nbest" in params.decoding_method:
key += f"_num_paths_{params.num_paths}_"
key += f"nbest_scale_{params.nbest_scale}"
if "LG" in params.decoding_method:
key += f"_ngram_lm_scale_{params.ngram_lm_scale}"
return {key: hyps}
else:
return {f"beam_size_{params.beam_size}": hyps}
@ -374,6 +480,7 @@ def decode_dataset(
params: AttributeDict,
model: nn.Module,
sp: spm.SentencePieceProcessor,
word_table: Optional[k2.SymbolTable] = None,
decoding_graph: Optional[k2.Fsa] = None,
) -> Dict[str, List[Tuple[List[str], List[str]]]]:
"""Decode dataset.
@ -387,9 +494,12 @@ def decode_dataset(
The neural model.
sp:
The BPE model.
word_table:
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is fast_beam_search.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return a dict, whose key may be "greedy_search" if greedy search
is used, or it may be "beam_7" if beam size of 7 is used.
@ -407,7 +517,7 @@ def decode_dataset(
if params.decoding_method == "greedy_search":
log_interval = 50
else:
log_interval = 10
log_interval = 20
results = defaultdict(list)
for batch_idx, batch in enumerate(dl):
@ -417,6 +527,7 @@ def decode_dataset(
params=params,
model=model,
sp=sp,
word_table=word_table,
decoding_graph=decoding_graph,
batch=batch,
)
@ -499,6 +610,8 @@ def main():
"greedy_search",
"beam_search",
"fast_beam_search",
"fast_beam_search_nbest",
"fast_beam_search_nbest_LG",
"fast_beam_search_nbest_oracle",
"modified_beam_search",
)
@ -509,16 +622,15 @@ def main():
else:
params.suffix = f"epoch-{params.epoch}-avg-{params.avg}"
if params.decoding_method == "fast_beam_search":
if "fast_beam_search" in params.decoding_method:
params.suffix += f"-beam-{params.beam}"
params.suffix += f"-max-contexts-{params.max_contexts}"
params.suffix += f"-max-states-{params.max_states}"
elif params.decoding_method == "fast_beam_search_nbest_oracle":
params.suffix += f"-beam-{params.beam}"
params.suffix += f"-max-contexts-{params.max_contexts}"
params.suffix += f"-max-states-{params.max_states}"
params.suffix += f"-num-paths-{params.num_paths}"
params.suffix += f"-nbest-scale-{params.nbest_scale}"
if "nbest" in params.decoding_method:
params.suffix += f"-nbest-scale-{params.nbest_scale}"
params.suffix += f"-num-paths-{params.num_paths}"
if "LG" in params.decoding_method:
params.suffix += f"-ngram-lm-scale-{params.ngram_lm_scale}"
elif "beam_search" in params.decoding_method:
params.suffix += (
f"-{params.decoding_method}-beam-size-{params.beam_size}"
@ -539,9 +651,9 @@ def main():
sp = spm.SentencePieceProcessor()
sp.load(params.bpe_model)
# <blk> and <unk> is defined in local/train_bpe_model.py
# <blk> and <unk> are defined in local/train_bpe_model.py
params.blank_id = sp.piece_to_id("<blk>")
params.unk_id = sp.unk_id()
params.unk_id = sp.piece_to_id("<unk>")
params.vocab_size = sp.get_piece_size()
logging.info(params)
@ -583,13 +695,24 @@ def main():
model.device = device
model.unk_id = params.unk_id
if params.decoding_method in (
"fast_beam_search",
"fast_beam_search_nbest_oracle",
):
decoding_graph = k2.trivial_graph(params.vocab_size - 1, device=device)
if "fast_beam_search" in params.decoding_method:
if params.decoding_method == "fast_beam_search_nbest_LG":
lexicon = Lexicon(params.lang_dir)
word_table = lexicon.word_table
lg_filename = params.lang_dir / "LG.pt"
logging.info(f"Loading {lg_filename}")
decoding_graph = k2.Fsa.from_dict(
torch.load(lg_filename, map_location=device)
)
decoding_graph.scores *= params.ngram_lm_scale
else:
word_table = None
decoding_graph = k2.trivial_graph(
params.vocab_size - 1, device=device
)
else:
decoding_graph = None
word_table = None
num_param = sum([p.numel() for p in model.parameters()])
logging.info(f"Number of model parameters: {num_param}")
@ -612,6 +735,7 @@ def main():
params=params,
model=model,
sp=sp,
word_table=word_table,
decoding_graph=decoding_graph,
)

210
egs/librispeech/ASR/pruned_transducer_stateless4/decode.py
View File

@ -44,16 +44,53 @@ Usage:
--decoding-method modified_beam_search \
--beam-size 4
(4) fast beam search
(4) fast beam search (one best)
./pruned_transducer_stateless4/decode.py \
--epoch 30 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless4/exp \
--max-duration 600 \
--decoding-method fast_beam_search \
--beam 4 \
--max-contexts 4 \
--max-states 8
--beam 20.0 \
--max-contexts 8 \
--max-states 64
(5) fast beam search (nbest)
./pruned_transducer_stateless4/decode.py \
--epoch 30 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless3/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(6) fast beam search (nbest oracle WER)
./pruned_transducer_stateless4/decode.py \
--epoch 30 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless4/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_oracle \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(7) fast beam search (with LG)
./pruned_transducer_stateless4/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless4/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_LG \
--beam 20.0 \
--max-contexts 8 \
--max-states 64
"""
@ -70,6 +107,9 @@ import torch.nn as nn
from asr_datamodule import LibriSpeechAsrDataModule
from beam_search import (
beam_search,
fast_beam_search_nbest,
fast_beam_search_nbest_LG,
fast_beam_search_nbest_oracle,
fast_beam_search_one_best,
greedy_search,
greedy_search_batch,
@ -83,6 +123,7 @@ from icefall.checkpoint import (
find_checkpoints,
load_checkpoint,
)
from icefall.lexicon import Lexicon
from icefall.utils import (
AttributeDict,
setup_logger,
@ -150,6 +191,13 @@ def get_parser():
help="Path to the BPE model",
)
parser.add_argument(
"--lang-dir",
type=Path,
default="data/lang_bpe_500",
help="The lang dir containing word table and LG graph",
)
parser.add_argument(
"--decoding-method",
type=str,
@ -159,6 +207,11 @@ def get_parser():
- beam_search
- modified_beam_search
- fast_beam_search
- fast_beam_search_nbest
- fast_beam_search_nbest_oracle
- fast_beam_search_nbest_LG
If you use fast_beam_search_nbest_LG, you have to specify
`--lang-dir`, which should contain `LG.pt`.
""",
)
@ -174,27 +227,42 @@ def get_parser():
parser.add_argument(
"--beam",
type=float,
default=4,
default=20.0,
help="""A floating point value to calculate the cutoff score during beam
search (i.e., `cutoff = max-score - beam`), which is the same as the
`beam` in Kaldi.
Used only when --decoding-method is fast_beam_search""",
Used only when --decoding-method is fast_beam_search,
fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle
""",
)
parser.add_argument(
"--ngram-lm-scale",
type=float,
default=0.01,
help="""
Used only when --decoding_method is fast_beam_search_nbest_LG.
It specifies the scale for n-gram LM scores.
""",
)
parser.add_argument(
"--max-contexts",
type=int,
default=4,
default=8,
help="""Used only when --decoding-method is
fast_beam_search""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
"--max-states",
type=int,
default=8,
default=64,
help="""Used only when --decoding-method is
fast_beam_search""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
@ -212,6 +280,24 @@ def get_parser():
Used only when --decoding_method is greedy_search""",
)
parser.add_argument(
"--num-paths",
type=int,
default=200,
help="""Number of paths for nbest decoding.
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
"--nbest-scale",
type=float,
default=0.5,
help="""Scale applied to lattice scores when computing nbest paths.
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
return parser
@ -220,6 +306,7 @@ def decode_one_batch(
model: nn.Module,
sp: spm.SentencePieceProcessor,
batch: dict,
word_table: Optional[k2.SymbolTable] = None,
decoding_graph: Optional[k2.Fsa] = None,
) -> Dict[str, List[List[str]]]:
"""Decode one batch and return the result in a dict. The dict has the
@ -243,9 +330,12 @@ def decode_one_batch(
It is the return value from iterating
`lhotse.dataset.K2SpeechRecognitionDataset`. See its documentation
for the format of the `batch`.
word_table:
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is fast_beam_search.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return the decoding result. See above description for the format of
the returned dict.
@ -277,6 +367,49 @@ def decode_one_batch(
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_LG":
hyp_tokens = fast_beam_search_nbest_LG(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in hyp_tokens:
hyps.append([word_table[i] for i in hyp])
elif params.decoding_method == "fast_beam_search_nbest":
hyp_tokens = fast_beam_search_nbest(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_oracle":
hyp_tokens = fast_beam_search_nbest_oracle(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
ref_texts=sp.encode(supervisions["text"]),
nbest_scale=params.nbest_scale,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif (
params.decoding_method == "greedy_search"
and params.max_sym_per_frame == 1
@ -324,14 +457,17 @@ def decode_one_batch(
if params.decoding_method == "greedy_search":
return {"greedy_search": hyps}
elif params.decoding_method == "fast_beam_search":
return {
(
f"beam_{params.beam}_"
f"max_contexts_{params.max_contexts}_"
f"max_states_{params.max_states}"
): hyps
}
elif "fast_beam_search" in params.decoding_method:
key = f"beam_{params.beam}_"
key += f"max_contexts_{params.max_contexts}_"
key += f"max_states_{params.max_states}"
if "nbest" in params.decoding_method:
key += f"_num_paths_{params.num_paths}_"
key += f"nbest_scale_{params.nbest_scale}"
if "LG" in params.decoding_method:
key += f"_ngram_lm_scale_{params.ngram_lm_scale}"
return {key: hyps}
else:
return {f"beam_size_{params.beam_size}": hyps}
@ -341,6 +477,7 @@ def decode_dataset(
params: AttributeDict,
model: nn.Module,
sp: spm.SentencePieceProcessor,
word_table: Optional[k2.SymbolTable] = None,
decoding_graph: Optional[k2.Fsa] = None,
) -> Dict[str, List[Tuple[List[str], List[str]]]]:
"""Decode dataset.
@ -354,9 +491,12 @@ def decode_dataset(
The neural model.
sp:
The BPE model.
word_table:
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is fast_beam_search.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return a dict, whose key may be "greedy_search" if greedy search
is used, or it may be "beam_7" if beam size of 7 is used.
@ -374,7 +514,7 @@ def decode_dataset(
if params.decoding_method == "greedy_search":
log_interval = 50
else:
log_interval = 10
log_interval = 20
results = defaultdict(list)
for batch_idx, batch in enumerate(dl):
@ -385,6 +525,7 @@ def decode_dataset(
model=model,
sp=sp,
decoding_graph=decoding_graph,
word_table=word_table,
batch=batch,
)
@ -466,6 +607,9 @@ def main():
"greedy_search",
"beam_search",
"fast_beam_search",
"fast_beam_search_nbest",
"fast_beam_search_nbest_LG",
"fast_beam_search_nbest_oracle",
"modified_beam_search",
)
params.res_dir = params.exp_dir / params.decoding_method
@ -479,6 +623,11 @@ def main():
params.suffix += f"-beam-{params.beam}"
params.suffix += f"-max-contexts-{params.max_contexts}"
params.suffix += f"-max-states-{params.max_states}"
if "nbest" in params.decoding_method:
params.suffix += f"-nbest-scale-{params.nbest_scale}"
params.suffix += f"-num-paths-{params.num_paths}"
if "LG" in params.decoding_method:
params.suffix += f"-ngram-lm-scale-{params.ngram_lm_scale}"
elif "beam_search" in params.decoding_method:
params.suffix += (
f"-{params.decoding_method}-beam-size-{params.beam_size}"
@ -592,10 +741,24 @@ def main():
model.to(device)
model.eval()
if params.decoding_method == "fast_beam_search":
decoding_graph = k2.trivial_graph(params.vocab_size - 1, device=device)
if "fast_beam_search" in params.decoding_method:
if params.decoding_method == "fast_beam_search_nbest_LG":
lexicon = Lexicon(params.lang_dir)
word_table = lexicon.word_table
lg_filename = params.lang_dir / "LG.pt"
logging.info(f"Loading {lg_filename}")
decoding_graph = k2.Fsa.from_dict(
torch.load(lg_filename, map_location=device)
)
decoding_graph.scores *= params.ngram_lm_scale
else:
word_table = None
decoding_graph = k2.trivial_graph(
params.vocab_size - 1, device=device
)
else:
decoding_graph = None
word_table = None
num_param = sum([p.numel() for p in model.parameters()])
logging.info(f"Number of model parameters: {num_param}")
@ -617,6 +780,7 @@ def main():
params=params,
model=model,
sp=sp,
word_table=word_table,
decoding_graph=decoding_graph,
)

210
egs/librispeech/ASR/pruned_transducer_stateless5/decode.py
View File

@ -44,16 +44,53 @@ Usage:
--decoding-method modified_beam_search \
--beam-size 4
(4) fast beam search
(4) fast beam search (one best)
./pruned_transducer_stateless5/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless5/exp \
--max-duration 600 \
--decoding-method fast_beam_search \
--beam 4 \
--max-contexts 4 \
--max-states 8
--beam 20.0 \
--max-contexts 8 \
--max-states 64
(5) fast beam search (nbest)
./pruned_transducer_stateless5/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless5/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(6) fast beam search (nbest oracle WER)
./pruned_transducer_stateless5/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless5/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_oracle \
--beam 20.0 \
--max-contexts 8 \
--max-states 64 \
--num-paths 200 \
--nbest-scale 0.5
(7) fast beam search (with LG)
./pruned_transducer_stateless5/decode.py \
--epoch 28 \
--avg 15 \
--exp-dir ./pruned_transducer_stateless5/exp \
--max-duration 600 \
--decoding-method fast_beam_search_nbest_LG \
--beam 20.0 \
--max-contexts 8 \
--max-states 64
"""
@ -70,6 +107,9 @@ import torch.nn as nn
from asr_datamodule import LibriSpeechAsrDataModule
from beam_search import (
beam_search,
fast_beam_search_nbest,
fast_beam_search_nbest_LG,
fast_beam_search_nbest_oracle,
fast_beam_search_one_best,
greedy_search,
greedy_search_batch,
@ -83,6 +123,7 @@ from icefall.checkpoint import (
find_checkpoints,
load_checkpoint,
)
from icefall.lexicon import Lexicon
from icefall.utils import (
AttributeDict,
setup_logger,
@ -128,7 +169,7 @@ def get_parser():
parser.add_argument(
"--use-averaged-model",
type=str2bool,
default=False,
default=True,
help="Whether to load averaged model. Currently it only supports "
"using --epoch. If True, it would decode with the averaged model "
"over the epoch range from `epoch-avg` (excluded) to `epoch`."
@ -150,6 +191,13 @@ def get_parser():
help="Path to the BPE model",
)
parser.add_argument(
"--lang-dir",
type=Path,
default="data/lang_bpe_500",
help="The lang dir containing word table and LG graph",
)
parser.add_argument(
"--decoding-method",
type=str,
@ -159,6 +207,11 @@ def get_parser():
- beam_search
- modified_beam_search
- fast_beam_search
- fast_beam_search_nbest
- fast_beam_search_nbest_oracle
- fast_beam_search_nbest_LG
If you use fast_beam_search_nbest_LG, you have to specify
`--lang-dir`, which should contain `LG.pt`.
""",
)
@ -174,27 +227,42 @@ def get_parser():
parser.add_argument(
"--beam",
type=float,
default=4,
default=20.0,
help="""A floating point value to calculate the cutoff score during beam
search (i.e., `cutoff = max-score - beam`), which is the same as the
`beam` in Kaldi.
Used only when --decoding-method is fast_beam_search""",
Used only when --decoding-method is fast_beam_search,
fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle
""",
)
parser.add_argument(
"--ngram-lm-scale",
type=float,
default=0.01,
help="""
Used only when --decoding_method is fast_beam_search_nbest_LG.
It specifies the scale for n-gram LM scores.
""",
)
parser.add_argument(
"--max-contexts",
type=int,
default=4,
default=8,
help="""Used only when --decoding-method is
fast_beam_search""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
"--max-states",
type=int,
default=8,
default=64,
help="""Used only when --decoding-method is
fast_beam_search""",
fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG,
and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
@ -212,6 +280,24 @@ def get_parser():
Used only when --decoding_method is greedy_search""",
)
parser.add_argument(
"--num-paths",
type=int,
default=200,
help="""Number of paths for nbest decoding.
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
parser.add_argument(
"--nbest-scale",
type=float,
default=0.5,
help="""Scale applied to lattice scores when computing nbest paths.
Used only when the decoding method is fast_beam_search_nbest,
fast_beam_search_nbest_LG, and fast_beam_search_nbest_oracle""",
)
add_model_arguments(parser)
return parser
@ -222,6 +308,7 @@ def decode_one_batch(
model: nn.Module,
sp: spm.SentencePieceProcessor,
batch: dict,
word_table: Optional[k2.SymbolTable] = None,
decoding_graph: Optional[k2.Fsa] = None,
) -> Dict[str, List[List[str]]]:
"""Decode one batch and return the result in a dict. The dict has the
@ -245,9 +332,12 @@ def decode_one_batch(
It is the return value from iterating
`lhotse.dataset.K2SpeechRecognitionDataset`. See its documentation
for the format of the `batch`.
word_table:
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is fast_beam_search.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return the decoding result. See above description for the format of
the returned dict.
@ -279,6 +369,49 @@ def decode_one_batch(
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_LG":
hyp_tokens = fast_beam_search_nbest_LG(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in hyp_tokens:
hyps.append([word_table[i] for i in hyp])
elif params.decoding_method == "fast_beam_search_nbest":
hyp_tokens = fast_beam_search_nbest(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
nbest_scale=params.nbest_scale,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif params.decoding_method == "fast_beam_search_nbest_oracle":
hyp_tokens = fast_beam_search_nbest_oracle(
model=model,
decoding_graph=decoding_graph,
encoder_out=encoder_out,
encoder_out_lens=encoder_out_lens,
beam=params.beam,
max_contexts=params.max_contexts,
max_states=params.max_states,
num_paths=params.num_paths,
ref_texts=sp.encode(supervisions["text"]),
nbest_scale=params.nbest_scale,
)
for hyp in sp.decode(hyp_tokens):
hyps.append(hyp.split())
elif (
params.decoding_method == "greedy_search"
and params.max_sym_per_frame == 1
@ -326,14 +459,17 @@ def decode_one_batch(
if params.decoding_method == "greedy_search":
return {"greedy_search": hyps}
elif params.decoding_method == "fast_beam_search":
return {
(
f"beam_{params.beam}_"
f"max_contexts_{params.max_contexts}_"
f"max_states_{params.max_states}"
): hyps
}
elif "fast_beam_search" in params.decoding_method:
key = f"beam_{params.beam}_"
key += f"max_contexts_{params.max_contexts}_"
key += f"max_states_{params.max_states}"
if "nbest" in params.decoding_method:
key += f"_num_paths_{params.num_paths}_"
key += f"nbest_scale_{params.nbest_scale}"
if "LG" in params.decoding_method:
key += f"_ngram_lm_scale_{params.ngram_lm_scale}"
return {key: hyps}
else:
return {f"beam_size_{params.beam_size}": hyps}
@ -343,6 +479,7 @@ def decode_dataset(
params: AttributeDict,
model: nn.Module,
sp: spm.SentencePieceProcessor,
word_table: Optional[k2.SymbolTable] = None,
decoding_graph: Optional[k2.Fsa] = None,
) -> Dict[str, List[Tuple[List[str], List[str]]]]:
"""Decode dataset.
@ -356,9 +493,12 @@ def decode_dataset(
The neural model.
sp:
The BPE model.
word_table:
The word symbol table.
decoding_graph:
The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
only when --decoding_method is fast_beam_search.
only when --decoding_method is fast_beam_search, fast_beam_search_nbest,
fast_beam_search_nbest_oracle, and fast_beam_search_nbest_LG.
Returns:
Return a dict, whose key may be "greedy_search" if greedy search
is used, or it may be "beam_7" if beam size of 7 is used.
@ -387,6 +527,7 @@ def decode_dataset(
model=model,
sp=sp,
decoding_graph=decoding_graph,
word_table=word_table,
batch=batch,
)
@ -468,6 +609,9 @@ def main():
"greedy_search",
"beam_search",
"fast_beam_search",
"fast_beam_search_nbest",
"fast_beam_search_nbest_LG",
"fast_beam_search_nbest_oracle",
"modified_beam_search",
)
params.res_dir = params.exp_dir / params.decoding_method
@ -481,6 +625,11 @@ def main():
params.suffix += f"-beam-{params.beam}"
params.suffix += f"-max-contexts-{params.max_contexts}"
params.suffix += f"-max-states-{params.max_states}"
if "nbest" in params.decoding_method:
params.suffix += f"-nbest-scale-{params.nbest_scale}"
params.suffix += f"-num-paths-{params.num_paths}"
if "LG" in params.decoding_method:
params.suffix += f"-ngram-lm-scale-{params.ngram_lm_scale}"
elif "beam_search" in params.decoding_method:
params.suffix += (
f"-{params.decoding_method}-beam-size-{params.beam_size}"
@ -594,10 +743,24 @@ def main():
model.to(device)
model.eval()
if params.decoding_method == "fast_beam_search":
decoding_graph = k2.trivial_graph(params.vocab_size - 1, device=device)
if "fast_beam_search" in params.decoding_method:
if params.decoding_method == "fast_beam_search_nbest_LG":
lexicon = Lexicon(params.lang_dir)
word_table = lexicon.word_table
lg_filename = params.lang_dir / "LG.pt"
logging.info(f"Loading {lg_filename}")
decoding_graph = k2.Fsa.from_dict(
torch.load(lg_filename, map_location=device)
)
decoding_graph.scores *= params.ngram_lm_scale
else:
word_table = None
decoding_graph = k2.trivial_graph(
params.vocab_size - 1, device=device
)
else:
decoding_graph = None
word_table = None
num_param = sum([p.numel() for p in model.parameters()])
logging.info(f"Number of model parameters: {num_param}")
@ -619,6 +782,7 @@ def main():
params=params,
model=model,
sp=sp,
word_table=word_table,
decoding_graph=decoding_graph,
)

6
icefall/decode.py
View File

@ -308,9 +308,7 @@ class Nbest(object):
del word_fsa.aux_labels
word_fsa.scores.zero_()
word_fsa_with_epsilon_loops = k2.remove_epsilon_and_add_self_loops(
word_fsa
)
word_fsa_with_epsilon_loops = k2.linear_fsa_with_self_loops(word_fsa)
path_to_utt_map = self.shape.row_ids(1)
@ -609,7 +607,7 @@ def rescore_with_n_best_list(
num_paths:
Size of nbest list.
lm_scale_list:
A list of float representing LM score scales.
A list of floats representing LM score scales.
nbest_scale:
Scale to be applied to ``lattice.score`` when sampling paths
using ``k2.random_paths``.