From 07b06f74631740cd63da642e3f0fda141c7a63e8 Mon Sep 17 00:00:00 2001 From: dohe0342 Date: Sat, 7 Jan 2023 13:53:05 +0900 Subject: [PATCH] from local --- .../ASR/incremental_transf/__init__.py | 0 .../ASR/incremental_transf/asr_datamodule.py | 453 ++++ .../ASR/incremental_transf/beam_search.py | 2342 +++++++++++++++++ .../ASR/incremental_transf/conformer.py | 1809 +++++++++++++ .../ASR/incremental_transf/decode.py | 972 +++++++ .../ASR/incremental_transf/decode_stream.py | 146 + .../ASR/incremental_transf/decoder.py | 123 + .../incremental_transf/encoder_interface.py | 43 + .../ASR/incremental_transf/export.py | 287 ++ .../ASR/incremental_transf/joiner.py | 69 + .../ASR/incremental_transf/lstmp.py | 102 + .../ASR/incremental_transf/model.py | 207 ++ .../ASR/incremental_transf/optim.py | 320 +++ .../ASR/incremental_transf/pretrained.py | 344 +++ .../ASR/incremental_transf/scaling.py | 1015 +++++++ .../incremental_transf/scaling_converter.py | 320 +++ .../streaming_beam_search.py | 282 ++ .../incremental_transf/streaming_decode.py | 653 +++++ .../ASR/incremental_transf/test_model.py | 65 + .../ASR/incremental_transf/train.py | 1195 +++++++++ 20 files changed, 10747 insertions(+) create mode 100644 egs/librispeech/ASR/incremental_transf/__init__.py create mode 100644 egs/librispeech/ASR/incremental_transf/asr_datamodule.py create mode 100644 egs/librispeech/ASR/incremental_transf/beam_search.py create mode 100644 egs/librispeech/ASR/incremental_transf/conformer.py create mode 100755 egs/librispeech/ASR/incremental_transf/decode.py create mode 100644 egs/librispeech/ASR/incremental_transf/decode_stream.py create mode 100644 egs/librispeech/ASR/incremental_transf/decoder.py create mode 100644 egs/librispeech/ASR/incremental_transf/encoder_interface.py create mode 100755 egs/librispeech/ASR/incremental_transf/export.py create mode 100644 egs/librispeech/ASR/incremental_transf/joiner.py create mode 100644 egs/librispeech/ASR/incremental_transf/lstmp.py create mode 100644 egs/librispeech/ASR/incremental_transf/model.py create mode 100644 egs/librispeech/ASR/incremental_transf/optim.py create mode 100755 egs/librispeech/ASR/incremental_transf/pretrained.py create mode 100644 egs/librispeech/ASR/incremental_transf/scaling.py create mode 100644 egs/librispeech/ASR/incremental_transf/scaling_converter.py create mode 100644 egs/librispeech/ASR/incremental_transf/streaming_beam_search.py create mode 100755 egs/librispeech/ASR/incremental_transf/streaming_decode.py create mode 100755 egs/librispeech/ASR/incremental_transf/test_model.py create mode 100755 egs/librispeech/ASR/incremental_transf/train.py diff --git a/egs/librispeech/ASR/incremental_transf/__init__.py b/egs/librispeech/ASR/incremental_transf/__init__.py new file mode 100644 index 000000000..e69de29bb diff --git a/egs/librispeech/ASR/incremental_transf/asr_datamodule.py b/egs/librispeech/ASR/incremental_transf/asr_datamodule.py new file mode 100644 index 000000000..c5787835d --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/asr_datamodule.py @@ -0,0 +1,453 @@ +# Copyright 2021 Piotr Żelasko +# Copyright 2022 Xiaomi Corporation (Author: Mingshuang Luo) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + + +import argparse +import inspect +import logging +from functools import lru_cache +from pathlib import Path +from typing import Any, Dict, Optional + +import torch +from lhotse import CutSet, Fbank, FbankConfig, load_manifest, load_manifest_lazy +from lhotse.dataset import ( # noqa F401 for PrecomputedFeatures + CutConcatenate, + CutMix, + DynamicBucketingSampler, + K2SpeechRecognitionDataset, + PrecomputedFeatures, + SingleCutSampler, + SpecAugment, +) +from lhotse.dataset.input_strategies import ( # noqa F401 For AudioSamples + AudioSamples, + OnTheFlyFeatures, +) +from lhotse.utils import fix_random_seed +from torch.utils.data import DataLoader + +from icefall.utils import str2bool + + +class _SeedWorkers: + def __init__(self, seed: int): + self.seed = seed + + def __call__(self, worker_id: int): + fix_random_seed(self.seed + worker_id) + + +class LibriSpeechAsrDataModule: + """ + DataModule for k2 ASR experiments. + It assumes there is always one train and valid dataloader, + but there can be multiple test dataloaders (e.g. LibriSpeech test-clean + and test-other). + + It contains all the common data pipeline modules used in ASR + experiments, e.g.: + - dynamic batch size, + - bucketing samplers, + - cut concatenation, + - augmentation, + - on-the-fly feature extraction + + This class should be derived for specific corpora used in ASR tasks. + """ + + def __init__(self, args: argparse.Namespace): + self.args = args + + @classmethod + def add_arguments(cls, parser: argparse.ArgumentParser): + group = parser.add_argument_group( + title="ASR data related options", + description="These options are used for the preparation of " + "PyTorch DataLoaders from Lhotse CutSet's -- they control the " + "effective batch sizes, sampling strategies, applied data " + "augmentations, etc.", + ) + group.add_argument( + "--full-libri", + type=str2bool, + default=True, + help="When enabled, use 960h LibriSpeech. Otherwise, use 100h subset.", + ) + group.add_argument( + "--manifest-dir", + type=Path, + default=Path("data/fbank"), + help="Path to directory with train/valid/test cuts.", + ) + group.add_argument( + "--max-duration", + type=int, + default=200.0, + help="Maximum pooled recordings duration (seconds) in a " + "single batch. You can reduce it if it causes CUDA OOM.", + ) + group.add_argument( + "--bucketing-sampler", + type=str2bool, + default=True, + help="When enabled, the batches will come from buckets of " + "similar duration (saves padding frames).", + ) + group.add_argument( + "--num-buckets", + type=int, + default=30, + help="The number of buckets for the DynamicBucketingSampler" + "(you might want to increase it for larger datasets).", + ) + group.add_argument( + "--concatenate-cuts", + type=str2bool, + default=False, + help="When enabled, utterances (cuts) will be concatenated " + "to minimize the amount of padding.", + ) + group.add_argument( + "--duration-factor", + type=float, + default=1.0, + help="Determines the maximum duration of a concatenated cut " + "relative to the duration of the longest cut in a batch.", + ) + group.add_argument( + "--gap", + type=float, + default=1.0, + help="The amount of padding (in seconds) inserted between " + "concatenated cuts. This padding is filled with noise when " + "noise augmentation is used.", + ) + group.add_argument( + "--on-the-fly-feats", + type=str2bool, + default=False, + help="When enabled, use on-the-fly cut mixing and feature " + "extraction. Will drop existing precomputed feature manifests " + "if available.", + ) + group.add_argument( + "--shuffle", + type=str2bool, + default=True, + help="When enabled (=default), the examples will be " + "shuffled for each epoch.", + ) + group.add_argument( + "--drop-last", + type=str2bool, + default=True, + help="Whether to drop last batch. Used by sampler.", + ) + group.add_argument( + "--return-cuts", + type=str2bool, + default=True, + help="When enabled, each batch will have the " + "field: batch['supervisions']['cut'] with the cuts that " + "were used to construct it.", + ) + + group.add_argument( + "--num-workers", + type=int, + default=2, + help="The number of training dataloader workers that " + "collect the batches.", + ) + + group.add_argument( + "--enable-spec-aug", + type=str2bool, + default=True, + help="When enabled, use SpecAugment for training dataset.", + ) + + group.add_argument( + "--spec-aug-time-warp-factor", + type=int, + default=80, + help="Used only when --enable-spec-aug is True. " + "It specifies the factor for time warping in SpecAugment. " + "Larger values mean more warping. " + "A value less than 1 means to disable time warp.", + ) + + group.add_argument( + "--enable-musan", + type=str2bool, + default=True, + help="When enabled, select noise from MUSAN and mix it" + "with training dataset. ", + ) + + group.add_argument( + "--input-strategy", + type=str, + default="PrecomputedFeatures", + help="AudioSamples or PrecomputedFeatures", + ) + + def train_dataloaders( + self, + cuts_train: CutSet, + sampler_state_dict: Optional[Dict[str, Any]] = None, + ) -> DataLoader: + """ + Args: + cuts_train: + CutSet for training. + sampler_state_dict: + The state dict for the training sampler. + """ + transforms = [] + if self.args.enable_musan: + logging.info("Enable MUSAN") + logging.info("About to get Musan cuts") + cuts_musan = load_manifest(self.args.manifest_dir / "musan_cuts.jsonl.gz") + transforms.append( + CutMix(cuts=cuts_musan, prob=0.5, snr=(10, 20), preserve_id=True) + ) + else: + logging.info("Disable MUSAN") + + if self.args.concatenate_cuts: + logging.info( + f"Using cut concatenation with duration factor " + f"{self.args.duration_factor} and gap {self.args.gap}." + ) + # Cut concatenation should be the first transform in the list, + # so that if we e.g. mix noise in, it will fill the gaps between + # different utterances. + transforms = [ + CutConcatenate( + duration_factor=self.args.duration_factor, gap=self.args.gap + ) + ] + transforms + + input_transforms = [] + if self.args.enable_spec_aug: + logging.info("Enable SpecAugment") + logging.info(f"Time warp factor: {self.args.spec_aug_time_warp_factor}") + # Set the value of num_frame_masks according to Lhotse's version. + # In different Lhotse's versions, the default of num_frame_masks is + # different. + num_frame_masks = 10 + num_frame_masks_parameter = inspect.signature( + SpecAugment.__init__ + ).parameters["num_frame_masks"] + if num_frame_masks_parameter.default == 1: + num_frame_masks = 2 + logging.info(f"Num frame mask: {num_frame_masks}") + input_transforms.append( + SpecAugment( + time_warp_factor=self.args.spec_aug_time_warp_factor, + num_frame_masks=num_frame_masks, + features_mask_size=27, + num_feature_masks=2, + frames_mask_size=100, + ) + ) + else: + logging.info("Disable SpecAugment") + + logging.info("About to create train dataset") + train = K2SpeechRecognitionDataset( + input_strategy=eval(self.args.input_strategy)(), + cut_transforms=transforms, + input_transforms=input_transforms, + return_cuts=self.args.return_cuts, + ) + + if self.args.on_the_fly_feats: + # NOTE: the PerturbSpeed transform should be added only if we + # remove it from data prep stage. + # Add on-the-fly speed perturbation; since originally it would + # have increased epoch size by 3, we will apply prob 2/3 and use + # 3x more epochs. + # Speed perturbation probably should come first before + # concatenation, but in principle the transforms order doesn't have + # to be strict (e.g. could be randomized) + # transforms = [PerturbSpeed(factors=[0.9, 1.1], p=2/3)] + transforms # noqa + # Drop feats to be on the safe side. + train = K2SpeechRecognitionDataset( + cut_transforms=transforms, + input_strategy=OnTheFlyFeatures(Fbank(FbankConfig(num_mel_bins=80))), + input_transforms=input_transforms, + return_cuts=self.args.return_cuts, + ) + + if self.args.bucketing_sampler: + logging.info("Using DynamicBucketingSampler.") + train_sampler = DynamicBucketingSampler( + cuts_train, + max_duration=self.args.max_duration, + shuffle=self.args.shuffle, + num_buckets=self.args.num_buckets, + drop_last=self.args.drop_last, + ) + else: + logging.info("Using SingleCutSampler.") + train_sampler = SingleCutSampler( + cuts_train, + max_duration=self.args.max_duration, + shuffle=self.args.shuffle, + ) + logging.info("About to create train dataloader") + + if sampler_state_dict is not None: + logging.info("Loading sampler state dict") + train_sampler.load_state_dict(sampler_state_dict) + + # 'seed' is derived from the current random state, which will have + # previously been set in the main process. + seed = torch.randint(0, 100000, ()).item() + worker_init_fn = _SeedWorkers(seed) + + train_dl = DataLoader( + train, + sampler=train_sampler, + batch_size=None, + num_workers=self.args.num_workers, + persistent_workers=False, + worker_init_fn=worker_init_fn, + ) + + return train_dl + + def valid_dataloaders(self, cuts_valid: CutSet) -> DataLoader: + transforms = [] + if self.args.concatenate_cuts: + transforms = [ + CutConcatenate( + duration_factor=self.args.duration_factor, gap=self.args.gap + ) + ] + transforms + + logging.info("About to create dev dataset") + if self.args.on_the_fly_feats: + validate = K2SpeechRecognitionDataset( + cut_transforms=transforms, + input_strategy=OnTheFlyFeatures(Fbank(FbankConfig(num_mel_bins=80))), + return_cuts=self.args.return_cuts, + ) + else: + validate = K2SpeechRecognitionDataset( + cut_transforms=transforms, + return_cuts=self.args.return_cuts, + ) + valid_sampler = DynamicBucketingSampler( + cuts_valid, + max_duration=self.args.max_duration, + shuffle=False, + ) + logging.info("About to create dev dataloader") + valid_dl = DataLoader( + validate, + sampler=valid_sampler, + batch_size=None, + num_workers=2, + persistent_workers=False, + ) + + return valid_dl + + def test_dataloaders(self, cuts: CutSet) -> DataLoader: + logging.debug("About to create test dataset") + test = K2SpeechRecognitionDataset( + input_strategy=OnTheFlyFeatures(Fbank(FbankConfig(num_mel_bins=80))) + if self.args.on_the_fly_feats + else eval(self.args.input_strategy)(), + return_cuts=self.args.return_cuts, + ) + sampler = DynamicBucketingSampler( + cuts, + max_duration=self.args.max_duration, + shuffle=False, + ) + logging.debug("About to create test dataloader") + test_dl = DataLoader( + test, + batch_size=None, + sampler=sampler, + num_workers=self.args.num_workers, + ) + return test_dl + + @lru_cache() + def train_clean_100_cuts(self) -> CutSet: + logging.info("About to get train-clean-100 cuts") + return load_manifest_lazy( + self.args.manifest_dir / "librispeech_cuts_train-clean-100.jsonl.gz" + ) + + @lru_cache() + def train_clean_360_cuts(self) -> CutSet: + logging.info("About to get train-clean-360 cuts") + return load_manifest_lazy( + self.args.manifest_dir / "librispeech_cuts_train-clean-360.jsonl.gz" + ) + + @lru_cache() + def train_other_500_cuts(self) -> CutSet: + logging.info("About to get train-other-500 cuts") + return load_manifest_lazy( + self.args.manifest_dir / "librispeech_cuts_train-other-500.jsonl.gz" + ) + + @lru_cache() + def train_all_shuf_cuts(self) -> CutSet: + logging.info( + "About to get the shuffled train-clean-100, \ + train-clean-360 and train-other-500 cuts" + ) + return load_manifest_lazy( + self.args.manifest_dir / "librispeech_cuts_train-all-shuf.jsonl.gz" + ) + + @lru_cache() + def dev_clean_cuts(self) -> CutSet: + logging.info("About to get dev-clean cuts") + return load_manifest_lazy( + self.args.manifest_dir / "librispeech_cuts_dev-clean.jsonl.gz" + ) + + @lru_cache() + def dev_other_cuts(self) -> CutSet: + logging.info("About to get dev-other cuts") + return load_manifest_lazy( + self.args.manifest_dir / "librispeech_cuts_dev-other.jsonl.gz" + ) + + @lru_cache() + def test_clean_cuts(self) -> CutSet: + logging.info("About to get test-clean cuts") + return load_manifest_lazy( + self.args.manifest_dir / "librispeech_cuts_test-clean.jsonl.gz" + ) + + @lru_cache() + def test_other_cuts(self) -> CutSet: + logging.info("About to get test-other cuts") + return load_manifest_lazy( + self.args.manifest_dir / "librispeech_cuts_test-other.jsonl.gz" + ) diff --git a/egs/librispeech/ASR/incremental_transf/beam_search.py b/egs/librispeech/ASR/incremental_transf/beam_search.py new file mode 100644 index 000000000..b324cc9b7 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/beam_search.py @@ -0,0 +1,2342 @@ +# Copyright 2021 Xiaomi Corp. (authors: Fangjun Kuang +# Xiaoyu Yang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import warnings +from dataclasses import dataclass, field +from typing import Dict, List, Optional, Tuple, Union + +import k2 +import sentencepiece as spm +import torch +from model import Transducer + +from icefall import NgramLm, NgramLmStateCost +from icefall.decode import Nbest, one_best_decoding +from icefall.rnn_lm.model import RnnLmModel +from icefall.utils import ( + DecodingResults, + add_eos, + add_sos, + get_texts, + get_texts_with_timestamp, +) + + +def fast_beam_search_one_best( + model: Transducer, + decoding_graph: k2.Fsa, + encoder_out: torch.Tensor, + encoder_out_lens: torch.Tensor, + beam: float, + max_states: int, + max_contexts: int, + temperature: float = 1.0, + return_timestamps: bool = False, +) -> Union[List[List[int]], DecodingResults]: + """It limits the maximum number of symbols per frame to 1. + + A lattice is first obtained using fast beam search, and then + the shortest path within the lattice is used as the final output. + + Args: + model: + An instance of `Transducer`. + decoding_graph: + Decoding graph used for decoding, may be a TrivialGraph or a LG. + 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. + temperature: + Softmax temperature. + return_timestamps: + Whether to return timestamps. + Returns: + If return_timestamps is False, return the decoded result. + Else, return a DecodingResults object containing + decoded result and corresponding timestamps. + """ + 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, + temperature=temperature, + ) + + best_path = one_best_decoding(lattice) + + if not return_timestamps: + return get_texts(best_path) + else: + return get_texts_with_timestamp(best_path) + + +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, + temperature: float = 1.0, + return_timestamps: bool = False, +) -> Union[List[List[int]], DecodingResults]: + """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 LG. + 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. + temperature: + Softmax temperature. + return_timestamps: + Whether to return timestamps. + Returns: + If return_timestamps is False, return the decoded result. + Else, return a DecodingResults object containing + decoded result and corresponding timestamps. + """ + 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, + temperature=temperature, + ) + + 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) + + if not return_timestamps: + return get_texts(best_path) + else: + return get_texts_with_timestamp(best_path) + + +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, + temperature: float = 1.0, + return_timestamps: bool = False, +) -> Union[List[List[int]], DecodingResults]: + """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 LG. + 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. + temperature: + Softmax temperature. + return_timestamps: + Whether to return timestamps. + Returns: + If return_timestamps is False, return the decoded result. + Else, return a DecodingResults object containing + decoded result and corresponding timestamps. + """ + 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, + temperature=temperature, + ) + + 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) + + if not return_timestamps: + return get_texts(best_path) + else: + return get_texts_with_timestamp(best_path) + + +def fast_beam_search_nbest_oracle( + 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, + ref_texts: List[List[int]], + use_double_scores: bool = True, + nbest_scale: float = 0.5, + temperature: float = 1.0, + return_timestamps: bool = False, +) -> Union[List[List[int]], DecodingResults]: + """It limits the maximum number of symbols per frame to 1. + + 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. + + This is the best result we can achieve for any nbest based rescoring + methods. + + Args: + model: + An instance of `Transducer`. + decoding_graph: + Decoding graph used for decoding, may be a TrivialGraph or a LG. + 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. + ref_texts: + A list-of-list of integers containing the reference transcripts. + If the decoding_graph is a trivial_graph, the integer ID is the + BPE token ID. + use_double_scores: + True to use double precision for computation. False to use + single precision. + nbest_scale: + It's the scale applied to the lattice.scores. A smaller value + yields more unique paths. + temperature: + Softmax temperature. + return_timestamps: + Whether to return timestamps. + Returns: + If return_timestamps is False, return the decoded result. + Else, return a DecodingResults object containing + decoded result and corresponding timestamps. + """ + 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, + temperature=temperature, + ) + + nbest = Nbest.from_lattice( + lattice=lattice, + num_paths=num_paths, + use_double_scores=use_double_scores, + nbest_scale=nbest_scale, + ) + + hyps = nbest.build_levenshtein_graphs() + refs = k2.levenshtein_graph(ref_texts, device=hyps.device) + + levenshtein_alignment = k2.levenshtein_alignment( + refs=refs, + hyps=hyps, + hyp_to_ref_map=nbest.shape.row_ids(1), + sorted_match_ref=True, + ) + + tot_scores = levenshtein_alignment.get_tot_scores( + use_double_scores=False, log_semiring=False + ) + ragged_tot_scores = k2.RaggedTensor(nbest.shape, tot_scores) + + max_indexes = ragged_tot_scores.argmax() + + best_path = k2.index_fsa(nbest.fsa, max_indexes) + + if not return_timestamps: + return get_texts(best_path) + else: + return get_texts_with_timestamp(best_path) + + +def fast_beam_search( + model: Transducer, + decoding_graph: k2.Fsa, + encoder_out: torch.Tensor, + encoder_out_lens: torch.Tensor, + beam: float, + max_states: int, + max_contexts: int, + temperature: float = 1.0, +) -> k2.Fsa: + """It limits the maximum number of symbols per frame to 1. + + Args: + model: + An instance of `Transducer`. + decoding_graph: + Decoding graph used for decoding, may be a TrivialGraph or a LG. + 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. + temperature: + Softmax temperature. + Returns: + Return an FsaVec with axes [utt][state][arc] containing the decoded + lattice. Note: When the input graph is a TrivialGraph, the returned + lattice is actually an acceptor. + """ + assert encoder_out.ndim == 3 + + context_size = model.decoder.context_size + vocab_size = model.decoder.vocab_size + + B, T, C = encoder_out.shape + + config = k2.RnntDecodingConfig( + vocab_size=vocab_size, + decoder_history_len=context_size, + beam=beam, + max_contexts=max_contexts, + max_states=max_states, + ) + individual_streams = [] + for i in range(B): + individual_streams.append(k2.RnntDecodingStream(decoding_graph)) + decoding_streams = k2.RnntDecodingStreams(individual_streams, config) + + encoder_out = model.joiner.encoder_proj(encoder_out) + + for t in range(T): + # shape is a RaggedShape of shape (B, context) + # contexts is a Tensor of shape (shape.NumElements(), context_size) + shape, contexts = decoding_streams.get_contexts() + # `nn.Embedding()` in torch below v1.7.1 supports only torch.int64 + contexts = contexts.to(torch.int64) + # decoder_out is of shape (shape.NumElements(), 1, decoder_out_dim) + decoder_out = model.decoder(contexts, need_pad=False) + decoder_out = model.joiner.decoder_proj(decoder_out) + # current_encoder_out is of shape + # (shape.NumElements(), 1, joiner_dim) + # fmt: off + current_encoder_out = torch.index_select( + encoder_out[:, t:t + 1, :], 0, shape.row_ids(1).to(torch.int64) + ) + # fmt: on + logits = model.joiner( + current_encoder_out.unsqueeze(2), + decoder_out.unsqueeze(1), + project_input=False, + ) + logits = logits.squeeze(1).squeeze(1) + log_probs = (logits / temperature).log_softmax(dim=-1) + decoding_streams.advance(log_probs) + decoding_streams.terminate_and_flush_to_streams() + lattice = decoding_streams.format_output(encoder_out_lens.tolist()) + + return lattice + + +def greedy_search( + model: Transducer, + encoder_out: torch.Tensor, + max_sym_per_frame: int, + return_timestamps: bool = False, +) -> Union[List[int], DecodingResults]: + """Greedy search for a single utterance. + Args: + model: + An instance of `Transducer`. + encoder_out: + A tensor of shape (N, T, C) from the encoder. Support only N==1 for now. + max_sym_per_frame: + Maximum number of symbols per frame. If it is set to 0, the WER + would be 100%. + return_timestamps: + Whether to return timestamps. + Returns: + If return_timestamps is False, return the decoded result. + Else, return a DecodingResults object containing + decoded result and corresponding timestamps. + """ + assert encoder_out.ndim == 3 + + # support only batch_size == 1 for now + assert encoder_out.size(0) == 1, encoder_out.size(0) + + blank_id = model.decoder.blank_id + context_size = model.decoder.context_size + unk_id = getattr(model, "unk_id", blank_id) + + device = next(model.parameters()).device + + decoder_input = torch.tensor( + [-1] * (context_size - 1) + [blank_id], device=device, dtype=torch.int64 + ).reshape(1, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False) + decoder_out = model.joiner.decoder_proj(decoder_out) + + encoder_out = model.joiner.encoder_proj(encoder_out) + + T = encoder_out.size(1) + t = 0 + hyp = [blank_id] * context_size + + # timestamp[i] is the frame index after subsampling + # on which hyp[i] is decoded + timestamp = [] + + # Maximum symbols per utterance. + max_sym_per_utt = 1000 + + # symbols per frame + sym_per_frame = 0 + + # symbols per utterance decoded so far + sym_per_utt = 0 + + while t < T and sym_per_utt < max_sym_per_utt: + if sym_per_frame >= max_sym_per_frame: + sym_per_frame = 0 + t += 1 + continue + + # fmt: off + current_encoder_out = encoder_out[:, t:t+1, :].unsqueeze(2) + # fmt: on + logits = model.joiner( + current_encoder_out, decoder_out.unsqueeze(1), project_input=False + ) + # logits is (1, 1, 1, vocab_size) + + y = logits.argmax().item() + if y not in (blank_id, unk_id): + hyp.append(y) + timestamp.append(t) + decoder_input = torch.tensor([hyp[-context_size:]], device=device).reshape( + 1, context_size + ) + + decoder_out = model.decoder(decoder_input, need_pad=False) + decoder_out = model.joiner.decoder_proj(decoder_out) + + sym_per_utt += 1 + sym_per_frame += 1 + else: + sym_per_frame = 0 + t += 1 + hyp = hyp[context_size:] # remove blanks + + if not return_timestamps: + return hyp + else: + return DecodingResults( + hyps=[hyp], + timestamps=[timestamp], + ) + + +def greedy_search_batch( + model: Transducer, + encoder_out: torch.Tensor, + encoder_out_lens: torch.Tensor, + return_timestamps: bool = False, +) -> Union[List[List[int]], DecodingResults]: + """Greedy search in batch mode. It hardcodes --max-sym-per-frame=1. + Args: + model: + The transducer model. + encoder_out: + Output from the encoder. Its shape is (N, T, C), where N >= 1. + encoder_out_lens: + A 1-D tensor of shape (N,), containing number of valid frames in + encoder_out before padding. + return_timestamps: + Whether to return timestamps. + Returns: + If return_timestamps is False, return the decoded result. + Else, return a DecodingResults object containing + decoded result and corresponding timestamps. + """ + assert encoder_out.ndim == 3 + assert encoder_out.size(0) >= 1, encoder_out.size(0) + + packed_encoder_out = torch.nn.utils.rnn.pack_padded_sequence( + input=encoder_out, + lengths=encoder_out_lens.cpu(), + batch_first=True, + enforce_sorted=False, + ) + + device = next(model.parameters()).device + + blank_id = model.decoder.blank_id + unk_id = getattr(model, "unk_id", blank_id) + context_size = model.decoder.context_size + + batch_size_list = packed_encoder_out.batch_sizes.tolist() + N = encoder_out.size(0) + assert torch.all(encoder_out_lens > 0), encoder_out_lens + assert N == batch_size_list[0], (N, batch_size_list) + + hyps = [[-1] * (context_size - 1) + [blank_id] for _ in range(N)] + + # timestamp[n][i] is the frame index after subsampling + # on which hyp[n][i] is decoded + timestamps = [[] for _ in range(N)] + + decoder_input = torch.tensor( + hyps, + device=device, + dtype=torch.int64, + ) # (N, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False) + decoder_out = model.joiner.decoder_proj(decoder_out) + # decoder_out: (N, 1, decoder_out_dim) + + encoder_out = model.joiner.encoder_proj(packed_encoder_out.data) + + offset = 0 + for (t, batch_size) in enumerate(batch_size_list): + start = offset + end = offset + batch_size + current_encoder_out = encoder_out.data[start:end] + current_encoder_out = current_encoder_out.unsqueeze(1).unsqueeze(1) + # current_encoder_out's shape: (batch_size, 1, 1, encoder_out_dim) + offset = end + + decoder_out = decoder_out[:batch_size] + + logits = model.joiner( + current_encoder_out, decoder_out.unsqueeze(1), project_input=False + ) + # logits'shape (batch_size, 1, 1, vocab_size) + + logits = logits.squeeze(1).squeeze(1) # (batch_size, vocab_size) + assert logits.ndim == 2, logits.shape + y = logits.argmax(dim=1).tolist() + emitted = False + for i, v in enumerate(y): + if v not in (blank_id, unk_id): + hyps[i].append(v) + timestamps[i].append(t) + emitted = True + if emitted: + # update decoder output + decoder_input = [h[-context_size:] for h in hyps[:batch_size]] + decoder_input = torch.tensor( + decoder_input, + device=device, + dtype=torch.int64, + ) + decoder_out = model.decoder(decoder_input, need_pad=False) + decoder_out = model.joiner.decoder_proj(decoder_out) + + sorted_ans = [h[context_size:] for h in hyps] + ans = [] + ans_timestamps = [] + unsorted_indices = packed_encoder_out.unsorted_indices.tolist() + for i in range(N): + ans.append(sorted_ans[unsorted_indices[i]]) + ans_timestamps.append(timestamps[unsorted_indices[i]]) + + if not return_timestamps: + return ans + else: + return DecodingResults( + hyps=ans, + timestamps=ans_timestamps, + ) + + +@dataclass +class Hypothesis: + # The predicted tokens so far. + # Newly predicted tokens are appended to `ys`. + ys: List[int] + + # The log prob of ys. + # It contains only one entry. + log_prob: torch.Tensor + + # timestamp[i] is the frame index after subsampling + # on which ys[i] is decoded + timestamp: List[int] = field(default_factory=list) + + # the lm score for next token given the current ys + lm_score: Optional[torch.Tensor] = None + + # the RNNLM states (h and c in LSTM) + state: Optional[Tuple[torch.Tensor, torch.Tensor]] = None + + # N-gram LM state + state_cost: Optional[NgramLmStateCost] = None + + @property + def key(self) -> str: + """Return a string representation of self.ys""" + return "_".join(map(str, self.ys)) + + +class HypothesisList(object): + def __init__(self, data: Optional[Dict[str, Hypothesis]] = None) -> None: + """ + Args: + data: + A dict of Hypotheses. Its key is its `value.key`. + """ + if data is None: + self._data = {} + else: + self._data = data + + @property + def data(self) -> Dict[str, Hypothesis]: + return self._data + + def add(self, hyp: Hypothesis) -> None: + """Add a Hypothesis to `self`. + + If `hyp` already exists in `self`, its probability is updated using + `log-sum-exp` with the existed one. + + Args: + hyp: + The hypothesis to be added. + """ + key = hyp.key + if key in self: + old_hyp = self._data[key] # shallow copy + torch.logaddexp(old_hyp.log_prob, hyp.log_prob, out=old_hyp.log_prob) + else: + self._data[key] = hyp + + def get_most_probable(self, length_norm: bool = False) -> Hypothesis: + """Get the most probable hypothesis, i.e., the one with + the largest `log_prob`. + + Args: + length_norm: + If True, the `log_prob` of a hypothesis is normalized by the + number of tokens in it. + Returns: + Return the hypothesis that has the largest `log_prob`. + """ + if length_norm: + return max(self._data.values(), key=lambda hyp: hyp.log_prob / len(hyp.ys)) + else: + return max(self._data.values(), key=lambda hyp: hyp.log_prob) + + def remove(self, hyp: Hypothesis) -> None: + """Remove a given hypothesis. + + Caution: + `self` is modified **in-place**. + + Args: + hyp: + The hypothesis to be removed from `self`. + Note: It must be contained in `self`. Otherwise, + an exception is raised. + """ + key = hyp.key + assert key in self, f"{key} does not exist" + del self._data[key] + + def filter(self, threshold: torch.Tensor) -> "HypothesisList": + """Remove all Hypotheses whose log_prob is less than threshold. + + Caution: + `self` is not modified. Instead, a new HypothesisList is returned. + + Returns: + Return a new HypothesisList containing all hypotheses from `self` + with `log_prob` being greater than the given `threshold`. + """ + ans = HypothesisList() + for _, hyp in self._data.items(): + if hyp.log_prob > threshold: + ans.add(hyp) # shallow copy + return ans + + def topk(self, k: int) -> "HypothesisList": + """Return the top-k hypothesis.""" + hyps = list(self._data.items()) + + hyps = sorted(hyps, key=lambda h: h[1].log_prob, reverse=True)[:k] + + ans = HypothesisList(dict(hyps)) + return ans + + def __contains__(self, key: str): + return key in self._data + + def __iter__(self): + return iter(self._data.values()) + + def __len__(self) -> int: + return len(self._data) + + def __str__(self) -> str: + s = [] + for key in self: + s.append(key) + return ", ".join(s) + + +def get_hyps_shape(hyps: List[HypothesisList]) -> k2.RaggedShape: + """Return a ragged shape with axes [utt][num_hyps]. + + Args: + hyps: + len(hyps) == batch_size. It contains the current hypothesis for + each utterance in the batch. + Returns: + Return a ragged shape with 2 axes [utt][num_hyps]. Note that + the shape is on CPU. + """ + num_hyps = [len(h) for h in hyps] + + # torch.cumsum() is inclusive sum, so we put a 0 at the beginning + # to get exclusive sum later. + num_hyps.insert(0, 0) + + num_hyps = torch.tensor(num_hyps) + row_splits = torch.cumsum(num_hyps, dim=0, dtype=torch.int32) + ans = k2.ragged.create_ragged_shape2( + row_splits=row_splits, cached_tot_size=row_splits[-1].item() + ) + return ans + + +def modified_beam_search( + model: Transducer, + encoder_out: torch.Tensor, + encoder_out_lens: torch.Tensor, + beam: int = 4, + temperature: float = 1.0, + return_timestamps: bool = False, +) -> Union[List[List[int]], DecodingResults]: + """Beam search in batch mode with --max-sym-per-frame=1 being hardcoded. + + Args: + model: + The transducer model. + encoder_out: + Output from the encoder. Its shape is (N, T, C). + encoder_out_lens: + A 1-D tensor of shape (N,), containing number of valid frames in + encoder_out before padding. + beam: + Number of active paths during the beam search. + temperature: + Softmax temperature. + return_timestamps: + Whether to return timestamps. + Returns: + If return_timestamps is False, return the decoded result. + Else, return a DecodingResults object containing + decoded result and corresponding timestamps. + """ + assert encoder_out.ndim == 3, encoder_out.shape + assert encoder_out.size(0) >= 1, encoder_out.size(0) + + packed_encoder_out = torch.nn.utils.rnn.pack_padded_sequence( + input=encoder_out, + lengths=encoder_out_lens.cpu(), + batch_first=True, + enforce_sorted=False, + ) + + blank_id = model.decoder.blank_id + unk_id = getattr(model, "unk_id", blank_id) + context_size = model.decoder.context_size + device = next(model.parameters()).device + + batch_size_list = packed_encoder_out.batch_sizes.tolist() + N = encoder_out.size(0) + assert torch.all(encoder_out_lens > 0), encoder_out_lens + assert N == batch_size_list[0], (N, batch_size_list) + + B = [HypothesisList() for _ in range(N)] + for i in range(N): + B[i].add( + Hypothesis( + ys=[blank_id] * context_size, + log_prob=torch.zeros(1, dtype=torch.float32, device=device), + timestamp=[], + ) + ) + + encoder_out = model.joiner.encoder_proj(packed_encoder_out.data) + + offset = 0 + finalized_B = [] + for (t, batch_size) in enumerate(batch_size_list): + start = offset + end = offset + batch_size + current_encoder_out = encoder_out.data[start:end] + current_encoder_out = current_encoder_out.unsqueeze(1).unsqueeze(1) + # current_encoder_out's shape is (batch_size, 1, 1, encoder_out_dim) + offset = end + + finalized_B = B[batch_size:] + finalized_B + B = B[:batch_size] + + hyps_shape = get_hyps_shape(B).to(device) + + A = [list(b) for b in B] + B = [HypothesisList() for _ in range(batch_size)] + + ys_log_probs = torch.cat( + [hyp.log_prob.reshape(1, 1) for hyps in A for hyp in hyps] + ) # (num_hyps, 1) + + decoder_input = torch.tensor( + [hyp.ys[-context_size:] for hyps in A for hyp in hyps], + device=device, + dtype=torch.int64, + ) # (num_hyps, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False).unsqueeze(1) + decoder_out = model.joiner.decoder_proj(decoder_out) + # decoder_out is of shape (num_hyps, 1, 1, joiner_dim) + + # Note: For torch 1.7.1 and below, it requires a torch.int64 tensor + # as index, so we use `to(torch.int64)` below. + current_encoder_out = torch.index_select( + current_encoder_out, + dim=0, + index=hyps_shape.row_ids(1).to(torch.int64), + ) # (num_hyps, 1, 1, encoder_out_dim) + + logits = model.joiner( + current_encoder_out, + decoder_out, + project_input=False, + ) # (num_hyps, 1, 1, vocab_size) + + logits = logits.squeeze(1).squeeze(1) # (num_hyps, vocab_size) + + log_probs = (logits / temperature).log_softmax(dim=-1) # (num_hyps, vocab_size) + + log_probs.add_(ys_log_probs) + + vocab_size = log_probs.size(-1) + + log_probs = log_probs.reshape(-1) + + row_splits = hyps_shape.row_splits(1) * vocab_size + log_probs_shape = k2.ragged.create_ragged_shape2( + row_splits=row_splits, cached_tot_size=log_probs.numel() + ) + ragged_log_probs = k2.RaggedTensor(shape=log_probs_shape, value=log_probs) + + for i in range(batch_size): + topk_log_probs, topk_indexes = ragged_log_probs[i].topk(beam) + + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + topk_hyp_indexes = (topk_indexes // vocab_size).tolist() + topk_token_indexes = (topk_indexes % vocab_size).tolist() + + for k in range(len(topk_hyp_indexes)): + hyp_idx = topk_hyp_indexes[k] + hyp = A[i][hyp_idx] + + new_ys = hyp.ys[:] + new_token = topk_token_indexes[k] + new_timestamp = hyp.timestamp[:] + if new_token not in (blank_id, unk_id): + new_ys.append(new_token) + new_timestamp.append(t) + + new_log_prob = topk_log_probs[k] + new_hyp = Hypothesis( + ys=new_ys, log_prob=new_log_prob, timestamp=new_timestamp + ) + B[i].add(new_hyp) + + B = B + finalized_B + best_hyps = [b.get_most_probable(length_norm=True) for b in B] + + sorted_ans = [h.ys[context_size:] for h in best_hyps] + sorted_timestamps = [h.timestamp for h in best_hyps] + ans = [] + ans_timestamps = [] + unsorted_indices = packed_encoder_out.unsorted_indices.tolist() + for i in range(N): + ans.append(sorted_ans[unsorted_indices[i]]) + ans_timestamps.append(sorted_timestamps[unsorted_indices[i]]) + + if not return_timestamps: + return ans + else: + return DecodingResults( + hyps=ans, + timestamps=ans_timestamps, + ) + + +def _deprecated_modified_beam_search( + model: Transducer, + encoder_out: torch.Tensor, + beam: int = 4, + return_timestamps: bool = False, +) -> Union[List[int], DecodingResults]: + """It limits the maximum number of symbols per frame to 1. + + It decodes only one utterance at a time. We keep it only for reference. + The function :func:`modified_beam_search` should be preferred as it + supports batch decoding. + + + Args: + model: + An instance of `Transducer`. + encoder_out: + A tensor of shape (N, T, C) from the encoder. Support only N==1 for now. + beam: + Beam size. + return_timestamps: + Whether to return timestamps. + + Returns: + If return_timestamps is False, return the decoded result. + Else, return a DecodingResults object containing + decoded result and corresponding timestamps. + """ + + assert encoder_out.ndim == 3 + + # support only batch_size == 1 for now + assert encoder_out.size(0) == 1, encoder_out.size(0) + blank_id = model.decoder.blank_id + unk_id = getattr(model, "unk_id", blank_id) + context_size = model.decoder.context_size + + device = next(model.parameters()).device + + T = encoder_out.size(1) + + B = HypothesisList() + B.add( + Hypothesis( + ys=[blank_id] * context_size, + log_prob=torch.zeros(1, dtype=torch.float32, device=device), + timestamp=[], + ) + ) + encoder_out = model.joiner.encoder_proj(encoder_out) + + for t in range(T): + # fmt: off + current_encoder_out = encoder_out[:, t:t+1, :].unsqueeze(2) + # current_encoder_out is of shape (1, 1, 1, encoder_out_dim) + # fmt: on + A = list(B) + B = HypothesisList() + + ys_log_probs = torch.cat([hyp.log_prob.reshape(1, 1) for hyp in A]) + # ys_log_probs is of shape (num_hyps, 1) + + decoder_input = torch.tensor( + [hyp.ys[-context_size:] for hyp in A], + device=device, + dtype=torch.int64, + ) + # decoder_input is of shape (num_hyps, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False).unsqueeze(1) + decoder_out = model.joiner.decoder_proj(decoder_out) + # decoder_output is of shape (num_hyps, 1, 1, joiner_dim) + + current_encoder_out = current_encoder_out.expand( + decoder_out.size(0), 1, 1, -1 + ) # (num_hyps, 1, 1, encoder_out_dim) + + logits = model.joiner( + current_encoder_out, + decoder_out, + project_input=False, + ) + # logits is of shape (num_hyps, 1, 1, vocab_size) + logits = logits.squeeze(1).squeeze(1) + + # now logits is of shape (num_hyps, vocab_size) + log_probs = logits.log_softmax(dim=-1) + + log_probs.add_(ys_log_probs) + + log_probs = log_probs.reshape(-1) + topk_log_probs, topk_indexes = log_probs.topk(beam) + + # topk_hyp_indexes are indexes into `A` + topk_hyp_indexes = topk_indexes // logits.size(-1) + topk_token_indexes = topk_indexes % logits.size(-1) + + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + topk_hyp_indexes = topk_hyp_indexes.tolist() + topk_token_indexes = topk_token_indexes.tolist() + + for i in range(len(topk_hyp_indexes)): + hyp = A[topk_hyp_indexes[i]] + new_ys = hyp.ys[:] + new_timestamp = hyp.timestamp[:] + new_token = topk_token_indexes[i] + if new_token not in (blank_id, unk_id): + new_ys.append(new_token) + new_timestamp.append(t) + new_log_prob = topk_log_probs[i] + new_hyp = Hypothesis( + ys=new_ys, log_prob=new_log_prob, timestamp=new_timestamp + ) + B.add(new_hyp) + + best_hyp = B.get_most_probable(length_norm=True) + ys = best_hyp.ys[context_size:] # [context_size:] to remove blanks + + if not return_timestamps: + return ys + else: + return DecodingResults(hyps=[ys], timestamps=[best_hyp.timestamp]) + + +def beam_search( + model: Transducer, + encoder_out: torch.Tensor, + beam: int = 4, + temperature: float = 1.0, + return_timestamps: bool = False, +) -> Union[List[int], DecodingResults]: + """ + It implements Algorithm 1 in https://arxiv.org/pdf/1211.3711.pdf + + espnet/nets/beam_search_transducer.py#L247 is used as a reference. + + Args: + model: + An instance of `Transducer`. + encoder_out: + A tensor of shape (N, T, C) from the encoder. Support only N==1 for now. + beam: + Beam size. + temperature: + Softmax temperature. + return_timestamps: + Whether to return timestamps. + + Returns: + If return_timestamps is False, return the decoded result. + Else, return a DecodingResults object containing + decoded result and corresponding timestamps. + """ + assert encoder_out.ndim == 3 + + # support only batch_size == 1 for now + assert encoder_out.size(0) == 1, encoder_out.size(0) + blank_id = model.decoder.blank_id + unk_id = getattr(model, "unk_id", blank_id) + context_size = model.decoder.context_size + + device = next(model.parameters()).device + + decoder_input = torch.tensor( + [blank_id] * context_size, + device=device, + dtype=torch.int64, + ).reshape(1, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False) + decoder_out = model.joiner.decoder_proj(decoder_out) + + encoder_out = model.joiner.encoder_proj(encoder_out) + + T = encoder_out.size(1) + t = 0 + + B = HypothesisList() + B.add(Hypothesis(ys=[blank_id] * context_size, log_prob=0.0, timestamp=[])) + + max_sym_per_utt = 20000 + + sym_per_utt = 0 + + decoder_cache: Dict[str, torch.Tensor] = {} + + while t < T and sym_per_utt < max_sym_per_utt: + # fmt: off + current_encoder_out = encoder_out[:, t:t+1, :].unsqueeze(2) + # fmt: on + A = B + B = HypothesisList() + + joint_cache: Dict[str, torch.Tensor] = {} + + # TODO(fangjun): Implement prefix search to update the `log_prob` + # of hypotheses in A + + while True: + y_star = A.get_most_probable() + A.remove(y_star) + + cached_key = y_star.key + + if cached_key not in decoder_cache: + decoder_input = torch.tensor( + [y_star.ys[-context_size:]], + device=device, + dtype=torch.int64, + ).reshape(1, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False) + decoder_out = model.joiner.decoder_proj(decoder_out) + decoder_cache[cached_key] = decoder_out + else: + decoder_out = decoder_cache[cached_key] + + cached_key += f"-t-{t}" + if cached_key not in joint_cache: + logits = model.joiner( + current_encoder_out, + decoder_out.unsqueeze(1), + project_input=False, + ) + + # TODO(fangjun): Scale the blank posterior + log_prob = (logits / temperature).log_softmax(dim=-1) + # log_prob is (1, 1, 1, vocab_size) + log_prob = log_prob.squeeze() + # Now log_prob is (vocab_size,) + joint_cache[cached_key] = log_prob + else: + log_prob = joint_cache[cached_key] + + # First, process the blank symbol + skip_log_prob = log_prob[blank_id] + new_y_star_log_prob = y_star.log_prob + skip_log_prob + + # ys[:] returns a copy of ys + B.add( + Hypothesis( + ys=y_star.ys[:], + log_prob=new_y_star_log_prob, + timestamp=y_star.timestamp[:], + ) + ) + + # Second, process other non-blank labels + values, indices = log_prob.topk(beam + 1) + for i, v in zip(indices.tolist(), values.tolist()): + if i in (blank_id, unk_id): + continue + new_ys = y_star.ys + [i] + new_log_prob = y_star.log_prob + v + new_timestamp = y_star.timestamp + [t] + A.add( + Hypothesis( + ys=new_ys, + log_prob=new_log_prob, + timestamp=new_timestamp, + ) + ) + + # Check whether B contains more than "beam" elements more probable + # than the most probable in A + A_most_probable = A.get_most_probable() + + kept_B = B.filter(A_most_probable.log_prob) + + if len(kept_B) >= beam: + B = kept_B.topk(beam) + break + + t += 1 + + best_hyp = B.get_most_probable(length_norm=True) + ys = best_hyp.ys[context_size:] # [context_size:] to remove blanks + + if not return_timestamps: + return ys + else: + return DecodingResults(hyps=[ys], timestamps=[best_hyp.timestamp]) + + +def fast_beam_search_with_nbest_rescoring( + model: Transducer, + decoding_graph: k2.Fsa, + encoder_out: torch.Tensor, + encoder_out_lens: torch.Tensor, + beam: float, + max_states: int, + max_contexts: int, + ngram_lm_scale_list: List[float], + num_paths: int, + G: k2.Fsa, + sp: spm.SentencePieceProcessor, + word_table: k2.SymbolTable, + oov_word: str = "", + use_double_scores: bool = True, + nbest_scale: float = 0.5, + temperature: float = 1.0, + return_timestamps: bool = False, +) -> Dict[str, Union[List[List[int]], DecodingResults]]: + """It limits the maximum number of symbols per frame to 1. + A lattice is first obtained using fast beam search, num_path are selected + and rescored using a given language model. The shortest path within the + lattice is used as the final output. + + Args: + model: + An instance of `Transducer`. + decoding_graph: + Decoding graph used for decoding, may be a TrivialGraph or a LG. + 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. + ngram_lm_scale_list: + A list of floats representing LM score scales. + num_paths: + Number of paths to extract from the decoded lattice. + G: + An FsaVec containing only a single FSA. It is an n-gram LM. + sp: + The BPE model. + word_table: + The word symbol table. + oov_word: + OOV words are replaced with this word. + use_double_scores: + True to use double precision for computation. False to use + single precision. + nbest_scale: + It's the scale applied to the lattice.scores. A smaller value + yields more unique paths. + temperature: + Softmax temperature. + return_timestamps: + Whether to return timestamps. + Returns: + Return the decoded result in a dict, where the key has the form + 'ngram_lm_scale_xx' and the value is the decoded results + optionally with timestamps. `xx` is the ngram LM scale value + used during decoding, i.e., 0.1. + """ + 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, + temperature=temperature, + ) + + 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 + + am_scores = nbest.tot_scores() + + # Now we need to compute the LM scores of each path. + # (1) Get the token IDs of each Path. We assume the decoding_graph + # is an acceptor, i.e., lattice is also an acceptor + tokens_shape = nbest.fsa.arcs.shape().remove_axis(1) # [path][arc] + + tokens = k2.RaggedTensor(tokens_shape, nbest.fsa.labels.contiguous()) + tokens = tokens.remove_values_leq(0) # remove -1 and 0 + + token_list: List[List[int]] = tokens.tolist() + word_list: List[List[str]] = sp.decode(token_list) + + assert isinstance(oov_word, str), oov_word + assert oov_word in word_table, oov_word + oov_word_id = word_table[oov_word] + + word_ids_list: List[List[int]] = [] + + for words in word_list: + this_word_ids = [] + for w in words.split(): + if w in word_table: + this_word_ids.append(word_table[w]) + else: + this_word_ids.append(oov_word_id) + word_ids_list.append(this_word_ids) + + word_fsas = k2.linear_fsa(word_ids_list, device=lattice.device) + word_fsas_with_self_loops = k2.add_epsilon_self_loops(word_fsas) + + num_unique_paths = len(word_ids_list) + + b_to_a_map = torch.zeros( + num_unique_paths, + dtype=torch.int32, + device=lattice.device, + ) + + rescored_word_fsas = k2.intersect_device( + a_fsas=G, + b_fsas=word_fsas_with_self_loops, + b_to_a_map=b_to_a_map, + sorted_match_a=True, + ret_arc_maps=False, + ) + + rescored_word_fsas = k2.remove_epsilon_self_loops(rescored_word_fsas) + rescored_word_fsas = k2.top_sort(k2.connect(rescored_word_fsas)) + ngram_lm_scores = rescored_word_fsas.get_tot_scores( + use_double_scores=True, + log_semiring=False, + ) + + ans: Dict[str, Union[List[List[int]], DecodingResults]] = {} + for s in ngram_lm_scale_list: + key = f"ngram_lm_scale_{s}" + tot_scores = am_scores.values + s * ngram_lm_scores + ragged_tot_scores = k2.RaggedTensor(nbest.shape, tot_scores) + max_indexes = ragged_tot_scores.argmax() + best_path = k2.index_fsa(nbest.fsa, max_indexes) + + if not return_timestamps: + ans[key] = get_texts(best_path) + else: + ans[key] = get_texts_with_timestamp(best_path) + + return ans + + +def fast_beam_search_with_nbest_rnn_rescoring( + model: Transducer, + decoding_graph: k2.Fsa, + encoder_out: torch.Tensor, + encoder_out_lens: torch.Tensor, + beam: float, + max_states: int, + max_contexts: int, + ngram_lm_scale_list: List[float], + num_paths: int, + G: k2.Fsa, + sp: spm.SentencePieceProcessor, + word_table: k2.SymbolTable, + rnn_lm_model: torch.nn.Module, + rnn_lm_scale_list: List[float], + oov_word: str = "", + use_double_scores: bool = True, + nbest_scale: float = 0.5, + temperature: float = 1.0, + return_timestamps: bool = False, +) -> Dict[str, Union[List[List[int]], DecodingResults]]: + """It limits the maximum number of symbols per frame to 1. + A lattice is first obtained using fast beam search, num_path are selected + and rescored using a given language model and a rnn-lm. + The shortest path within the lattice is used as the final output. + + Args: + model: + An instance of `Transducer`. + decoding_graph: + Decoding graph used for decoding, may be a TrivialGraph or a LG. + 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. + ngram_lm_scale_list: + A list of floats representing LM score scales. + num_paths: + Number of paths to extract from the decoded lattice. + G: + An FsaVec containing only a single FSA. It is an n-gram LM. + sp: + The BPE model. + word_table: + The word symbol table. + rnn_lm_model: + A rnn-lm model used for LM rescoring + rnn_lm_scale_list: + A list of floats representing RNN score scales. + oov_word: + OOV words are replaced with this word. + use_double_scores: + True to use double precision for computation. False to use + single precision. + nbest_scale: + It's the scale applied to the lattice.scores. A smaller value + yields more unique paths. + temperature: + Softmax temperature. + return_timestamps: + Whether to return timestamps. + Returns: + Return the decoded result in a dict, where the key has the form + 'ngram_lm_scale_xx' and the value is the decoded results + optionally with timestamps. `xx` is the ngram LM scale value + used during decoding, i.e., 0.1. + """ + 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, + temperature=temperature, + ) + + 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 + + am_scores = nbest.tot_scores() + + # Now we need to compute the LM scores of each path. + # (1) Get the token IDs of each Path. We assume the decoding_graph + # is an acceptor, i.e., lattice is also an acceptor + tokens_shape = nbest.fsa.arcs.shape().remove_axis(1) # [path][arc] + + tokens = k2.RaggedTensor(tokens_shape, nbest.fsa.labels.contiguous()) + tokens = tokens.remove_values_leq(0) # remove -1 and 0 + + token_list: List[List[int]] = tokens.tolist() + word_list: List[List[str]] = sp.decode(token_list) + + assert isinstance(oov_word, str), oov_word + assert oov_word in word_table, oov_word + oov_word_id = word_table[oov_word] + + word_ids_list: List[List[int]] = [] + + for words in word_list: + this_word_ids = [] + for w in words.split(): + if w in word_table: + this_word_ids.append(word_table[w]) + else: + this_word_ids.append(oov_word_id) + word_ids_list.append(this_word_ids) + + word_fsas = k2.linear_fsa(word_ids_list, device=lattice.device) + word_fsas_with_self_loops = k2.add_epsilon_self_loops(word_fsas) + + num_unique_paths = len(word_ids_list) + + b_to_a_map = torch.zeros( + num_unique_paths, + dtype=torch.int32, + device=lattice.device, + ) + + rescored_word_fsas = k2.intersect_device( + a_fsas=G, + b_fsas=word_fsas_with_self_loops, + b_to_a_map=b_to_a_map, + sorted_match_a=True, + ret_arc_maps=False, + ) + + rescored_word_fsas = k2.remove_epsilon_self_loops(rescored_word_fsas) + rescored_word_fsas = k2.top_sort(k2.connect(rescored_word_fsas)) + ngram_lm_scores = rescored_word_fsas.get_tot_scores( + use_double_scores=True, + log_semiring=False, + ) + + # Now RNN-LM + blank_id = model.decoder.blank_id + sos_id = sp.piece_to_id("sos_id") + eos_id = sp.piece_to_id("eos_id") + + sos_tokens = add_sos(tokens, sos_id) + tokens_eos = add_eos(tokens, eos_id) + sos_tokens_row_splits = sos_tokens.shape.row_splits(1) + sentence_lengths = sos_tokens_row_splits[1:] - sos_tokens_row_splits[:-1] + + x_tokens = sos_tokens.pad(mode="constant", padding_value=blank_id) + y_tokens = tokens_eos.pad(mode="constant", padding_value=blank_id) + + x_tokens = x_tokens.to(torch.int64) + y_tokens = y_tokens.to(torch.int64) + sentence_lengths = sentence_lengths.to(torch.int64) + + rnn_lm_nll = rnn_lm_model(x=x_tokens, y=y_tokens, lengths=sentence_lengths) + assert rnn_lm_nll.ndim == 2 + assert rnn_lm_nll.shape[0] == len(token_list) + rnn_lm_scores = -1 * rnn_lm_nll.sum(dim=1) + + ans: Dict[str, List[List[int]]] = {} + for n_scale in ngram_lm_scale_list: + for rnn_scale in rnn_lm_scale_list: + key = f"ngram_lm_scale_{n_scale}_rnn_lm_scale_{rnn_scale}" + tot_scores = ( + am_scores.values + n_scale * ngram_lm_scores + rnn_scale * rnn_lm_scores + ) + ragged_tot_scores = k2.RaggedTensor(nbest.shape, tot_scores) + max_indexes = ragged_tot_scores.argmax() + best_path = k2.index_fsa(nbest.fsa, max_indexes) + + if not return_timestamps: + ans[key] = get_texts(best_path) + else: + ans[key] = get_texts_with_timestamp(best_path) + + return ans + + +def modified_beam_search_ngram_rescoring( + model: Transducer, + encoder_out: torch.Tensor, + encoder_out_lens: torch.Tensor, + ngram_lm: NgramLm, + ngram_lm_scale: float, + beam: int = 4, + temperature: float = 1.0, +) -> List[List[int]]: + """Beam search in batch mode with --max-sym-per-frame=1 being hardcoded. + + Args: + model: + The transducer model. + encoder_out: + Output from the encoder. Its shape is (N, T, C). + encoder_out_lens: + A 1-D tensor of shape (N,), containing number of valid frames in + encoder_out before padding. + beam: + Number of active paths during the beam search. + temperature: + Softmax temperature. + Returns: + Return a list-of-list of token IDs. ans[i] is the decoding results + for the i-th utterance. + """ + assert encoder_out.ndim == 3, encoder_out.shape + assert encoder_out.size(0) >= 1, encoder_out.size(0) + + packed_encoder_out = torch.nn.utils.rnn.pack_padded_sequence( + input=encoder_out, + lengths=encoder_out_lens.cpu(), + batch_first=True, + enforce_sorted=False, + ) + + blank_id = model.decoder.blank_id + unk_id = getattr(model, "unk_id", blank_id) + context_size = model.decoder.context_size + device = next(model.parameters()).device + lm_scale = ngram_lm_scale + + batch_size_list = packed_encoder_out.batch_sizes.tolist() + N = encoder_out.size(0) + assert torch.all(encoder_out_lens > 0), encoder_out_lens + assert N == batch_size_list[0], (N, batch_size_list) + + B = [HypothesisList() for _ in range(N)] + for i in range(N): + B[i].add( + Hypothesis( + ys=[blank_id] * context_size, + log_prob=torch.zeros(1, dtype=torch.float32, device=device), + state_cost=NgramLmStateCost(ngram_lm), + ) + ) + + encoder_out = model.joiner.encoder_proj(packed_encoder_out.data) + + offset = 0 + finalized_B = [] + for batch_size in batch_size_list: + start = offset + end = offset + batch_size + current_encoder_out = encoder_out.data[start:end] + current_encoder_out = current_encoder_out.unsqueeze(1).unsqueeze(1) + # current_encoder_out's shape is (batch_size, 1, 1, encoder_out_dim) + offset = end + + finalized_B = B[batch_size:] + finalized_B + B = B[:batch_size] + + hyps_shape = get_hyps_shape(B).to(device) + + A = [list(b) for b in B] + B = [HypothesisList() for _ in range(batch_size)] + + ys_log_probs = torch.cat( + [ + hyp.log_prob.reshape(1, 1) + hyp.state_cost.lm_score * lm_scale + for hyps in A + for hyp in hyps + ] + ) # (num_hyps, 1) + + decoder_input = torch.tensor( + [hyp.ys[-context_size:] for hyps in A for hyp in hyps], + device=device, + dtype=torch.int64, + ) # (num_hyps, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False).unsqueeze(1) + decoder_out = model.joiner.decoder_proj(decoder_out) + # decoder_out is of shape (num_hyps, 1, 1, joiner_dim) + + # Note: For torch 1.7.1 and below, it requires a torch.int64 tensor + # as index, so we use `to(torch.int64)` below. + current_encoder_out = torch.index_select( + current_encoder_out, + dim=0, + index=hyps_shape.row_ids(1).to(torch.int64), + ) # (num_hyps, 1, 1, encoder_out_dim) + + logits = model.joiner( + current_encoder_out, + decoder_out, + project_input=False, + ) # (num_hyps, 1, 1, vocab_size) + + logits = logits.squeeze(1).squeeze(1) # (num_hyps, vocab_size) + + log_probs = (logits / temperature).log_softmax(dim=-1) # (num_hyps, vocab_size) + + log_probs.add_(ys_log_probs) + vocab_size = log_probs.size(-1) + log_probs = log_probs.reshape(-1) + + row_splits = hyps_shape.row_splits(1) * vocab_size + log_probs_shape = k2.ragged.create_ragged_shape2( + row_splits=row_splits, cached_tot_size=log_probs.numel() + ) + ragged_log_probs = k2.RaggedTensor(shape=log_probs_shape, value=log_probs) + + for i in range(batch_size): + topk_log_probs, topk_indexes = ragged_log_probs[i].topk(beam) + + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + topk_hyp_indexes = (topk_indexes // vocab_size).tolist() + topk_token_indexes = (topk_indexes % vocab_size).tolist() + + for k in range(len(topk_hyp_indexes)): + hyp_idx = topk_hyp_indexes[k] + hyp = A[i][hyp_idx] + + new_ys = hyp.ys[:] + new_token = topk_token_indexes[k] + if new_token not in (blank_id, unk_id): + new_ys.append(new_token) + state_cost = hyp.state_cost.forward_one_step(new_token) + else: + state_cost = hyp.state_cost + + # We only keep AM scores in new_hyp.log_prob + new_log_prob = topk_log_probs[k] - hyp.state_cost.lm_score * lm_scale + + new_hyp = Hypothesis( + ys=new_ys, log_prob=new_log_prob, state_cost=state_cost + ) + B[i].add(new_hyp) + + B = B + finalized_B + best_hyps = [b.get_most_probable(length_norm=True) for b in B] + + sorted_ans = [h.ys[context_size:] for h in best_hyps] + ans = [] + unsorted_indices = packed_encoder_out.unsorted_indices.tolist() + for i in range(N): + ans.append(sorted_ans[unsorted_indices[i]]) + + return ans + + +def modified_beam_search_rnnlm_shallow_fusion( + model: Transducer, + encoder_out: torch.Tensor, + encoder_out_lens: torch.Tensor, + sp: spm.SentencePieceProcessor, + rnnlm: RnnLmModel, + rnnlm_scale: float, + beam: int = 4, + return_timestamps: bool = False, +) -> List[List[int]]: + """Modified_beam_search + RNNLM shallow fusion + + Args: + model (Transducer): + The transducer model + encoder_out (torch.Tensor): + Encoder output in (N,T,C) + encoder_out_lens (torch.Tensor): + A 1-D tensor of shape (N,), containing the number of + valid frames in encoder_out before padding. + sp: + Sentence piece generator. + rnnlm (RnnLmModel): + RNNLM + rnnlm_scale (float): + scale of RNNLM in shallow fusion + beam (int, optional): + Beam size. Defaults to 4. + + Returns: + Return a list-of-list of token IDs. ans[i] is the decoding results + for the i-th utterance. + """ + assert encoder_out.ndim == 3, encoder_out.shape + assert encoder_out.size(0) >= 1, encoder_out.size(0) + assert rnnlm is not None + lm_scale = rnnlm_scale + vocab_size = rnnlm.vocab_size + + packed_encoder_out = torch.nn.utils.rnn.pack_padded_sequence( + input=encoder_out, + lengths=encoder_out_lens.cpu(), + batch_first=True, + enforce_sorted=False, + ) + + blank_id = model.decoder.blank_id + sos_id = sp.piece_to_id("") + unk_id = getattr(model, "unk_id", blank_id) + context_size = model.decoder.context_size + device = next(model.parameters()).device + + batch_size_list = packed_encoder_out.batch_sizes.tolist() + N = encoder_out.size(0) + assert torch.all(encoder_out_lens > 0), encoder_out_lens + assert N == batch_size_list[0], (N, batch_size_list) + + # get initial lm score and lm state by scoring the "sos" token + sos_token = torch.tensor([[sos_id]]).to(torch.int64).to(device) + init_score, init_states = rnnlm.score_token(sos_token) + + B = [HypothesisList() for _ in range(N)] + for i in range(N): + B[i].add( + Hypothesis( + ys=[blank_id] * context_size, + log_prob=torch.zeros(1, dtype=torch.float32, device=device), + state=init_states, + lm_score=init_score.reshape(-1), + timestamp=[], + ) + ) + + rnnlm.clean_cache() + encoder_out = model.joiner.encoder_proj(packed_encoder_out.data) + + offset = 0 + finalized_B = [] + for (t, batch_size) in enumerate(batch_size_list): + start = offset + end = offset + batch_size + current_encoder_out = encoder_out.data[start:end] # get batch + current_encoder_out = current_encoder_out.unsqueeze(1).unsqueeze(1) + # current_encoder_out's shape is (batch_size, 1, 1, encoder_out_dim) + offset = end + + finalized_B = B[batch_size:] + finalized_B + B = B[:batch_size] + + hyps_shape = get_hyps_shape(B).to(device) + + A = [list(b) for b in B] + B = [HypothesisList() for _ in range(batch_size)] + + ys_log_probs = torch.cat( + [hyp.log_prob.reshape(1, 1) for hyps in A for hyp in hyps] + ) + + decoder_input = torch.tensor( + [hyp.ys[-context_size:] for hyps in A for hyp in hyps], + device=device, + dtype=torch.int64, + ) # (num_hyps, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False).unsqueeze(1) + decoder_out = model.joiner.decoder_proj(decoder_out) + + current_encoder_out = torch.index_select( + current_encoder_out, + dim=0, + index=hyps_shape.row_ids(1).to(torch.int64), + ) # (num_hyps, 1, 1, encoder_out_dim) + + logits = model.joiner( + current_encoder_out, + decoder_out, + project_input=False, + ) # (num_hyps, 1, 1, vocab_size) + + logits = logits.squeeze(1).squeeze(1) # (num_hyps, vocab_size) + + log_probs = logits.log_softmax(dim=-1) # (num_hyps, vocab_size) + + log_probs.add_(ys_log_probs) + + vocab_size = log_probs.size(-1) + + log_probs = log_probs.reshape(-1) + + row_splits = hyps_shape.row_splits(1) * vocab_size + log_probs_shape = k2.ragged.create_ragged_shape2( + row_splits=row_splits, cached_tot_size=log_probs.numel() + ) + ragged_log_probs = k2.RaggedTensor(shape=log_probs_shape, value=log_probs) + """ + for all hyps with a non-blank new token, score this token. + It is a little confusing here because this for-loop + looks very similar to the one below. Here, we go through all + top-k tokens and only add the non-blanks ones to the token_list. + The RNNLM will score those tokens given the LM states. Note that + the variable `scores` is the LM score after seeing the new + non-blank token. + """ + token_list = [] + hs = [] + cs = [] + for i in range(batch_size): + topk_log_probs, topk_indexes = ragged_log_probs[i].topk(beam) + + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + topk_hyp_indexes = (topk_indexes // vocab_size).tolist() + topk_token_indexes = (topk_indexes % vocab_size).tolist() + for k in range(len(topk_hyp_indexes)): + hyp_idx = topk_hyp_indexes[k] + hyp = A[i][hyp_idx] + + new_token = topk_token_indexes[k] + if new_token not in (blank_id, unk_id): + assert new_token != 0, new_token + token_list.append([new_token]) + # store the LSTM states + hs.append(hyp.state[0]) + cs.append(hyp.state[1]) + + # forward RNNLM to get new states and scores + if len(token_list) != 0: + tokens_to_score = ( + torch.tensor(token_list).to(torch.int64).to(device).reshape(-1, 1) + ) + + hs = torch.cat(hs, dim=1).to(device) + cs = torch.cat(cs, dim=1).to(device) + scores, lm_states = rnnlm.score_token(tokens_to_score, (hs, cs)) + + count = 0 # index, used to locate score and lm states + for i in range(batch_size): + topk_log_probs, topk_indexes = ragged_log_probs[i].topk(beam) + + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + topk_hyp_indexes = (topk_indexes // vocab_size).tolist() + topk_token_indexes = (topk_indexes % vocab_size).tolist() + + for k in range(len(topk_hyp_indexes)): + hyp_idx = topk_hyp_indexes[k] + hyp = A[i][hyp_idx] + + ys = hyp.ys[:] + + lm_score = hyp.lm_score + state = hyp.state + + hyp_log_prob = topk_log_probs[k] # get score of current hyp + new_token = topk_token_indexes[k] + new_timestamp = hyp.timestamp[:] + if new_token not in (blank_id, unk_id): + + ys.append(new_token) + new_timestamp.append(t) + hyp_log_prob += lm_score[new_token] * lm_scale # add the lm score + + lm_score = scores[count] + state = ( + lm_states[0][:, count, :].unsqueeze(1), + lm_states[1][:, count, :].unsqueeze(1), + ) + count += 1 + + new_hyp = Hypothesis( + ys=ys, + log_prob=hyp_log_prob, + state=state, + lm_score=lm_score, + timestamp=new_timestamp, + ) + B[i].add(new_hyp) + + B = B + finalized_B + best_hyps = [b.get_most_probable(length_norm=True) for b in B] + + sorted_ans = [h.ys[context_size:] for h in best_hyps] + sorted_timestamps = [h.timestamp for h in best_hyps] + ans = [] + ans_timestamps = [] + unsorted_indices = packed_encoder_out.unsorted_indices.tolist() + for i in range(N): + ans.append(sorted_ans[unsorted_indices[i]]) + ans_timestamps.append(sorted_timestamps[unsorted_indices[i]]) + + if not return_timestamps: + return ans + else: + return DecodingResults( + tokens=ans, + timestamps=ans_timestamps, + ) + + +def modified_beam_search_rnnlm_LODR( + model: Transducer, + encoder_out: torch.Tensor, + encoder_out_lens: torch.Tensor, + sp: spm.SentencePieceProcessor, + LODR_lm: NgramLm, + LODR_lm_scale: float, + rnnlm: RnnLmModel, + rnnlm_scale: float, + beam: int = 4, +) -> List[List[int]]: + """This function implements LODR (https://arxiv.org/abs/2203.16776) with + `modified_beam_search`. It uses a bi-gram language model as the estimate + of the internal language model and subtracts its score during shallow fusion + with an external language model. This implementation uses a RNNLM as the + external language model. + + Args: + model (Transducer): + The transducer model + encoder_out (torch.Tensor): + Encoder output in (N,T,C) + encoder_out_lens (torch.Tensor): + A 1-D tensor of shape (N,), containing the number of + valid frames in encoder_out before padding. + sp: + Sentence piece generator. + LODR_lm: + A low order n-gram LM + LODR_lm_scale: + The scale of the LODR_lm + rnnlm (RnnLmModel): + RNNLM, the external language model + rnnlm_scale (float): + scale of RNNLM in shallow fusion + beam (int, optional): + Beam size. Defaults to 4. + + Returns: + Return a list-of-list of token IDs. ans[i] is the decoding results + for the i-th utterance. + + """ + assert encoder_out.ndim == 3, encoder_out.shape + assert encoder_out.size(0) >= 1, encoder_out.size(0) + assert rnnlm is not None + lm_scale = rnnlm_scale + vocab_size = rnnlm.vocab_size + + packed_encoder_out = torch.nn.utils.rnn.pack_padded_sequence( + input=encoder_out, + lengths=encoder_out_lens.cpu(), + batch_first=True, + enforce_sorted=False, + ) + + blank_id = model.decoder.blank_id + sos_id = sp.piece_to_id("") + unk_id = getattr(model, "unk_id", blank_id) + context_size = model.decoder.context_size + device = next(model.parameters()).device + + batch_size_list = packed_encoder_out.batch_sizes.tolist() + N = encoder_out.size(0) + assert torch.all(encoder_out_lens > 0), encoder_out_lens + assert N == batch_size_list[0], (N, batch_size_list) + + # get initial lm score and lm state by scoring the "sos" token + sos_token = torch.tensor([[sos_id]]).to(torch.int64).to(device) + init_score, init_states = rnnlm.score_token(sos_token) + + B = [HypothesisList() for _ in range(N)] + for i in range(N): + B[i].add( + Hypothesis( + ys=[blank_id] * context_size, + log_prob=torch.zeros(1, dtype=torch.float32, device=device), + state=init_states, # state of the RNNLM + lm_score=init_score.reshape(-1), + state_cost=NgramLmStateCost( + LODR_lm + ), # state of the source domain ngram + ) + ) + + rnnlm.clean_cache() + encoder_out = model.joiner.encoder_proj(packed_encoder_out.data) + + offset = 0 + finalized_B = [] + for batch_size in batch_size_list: + start = offset + end = offset + batch_size + current_encoder_out = encoder_out.data[start:end] # get batch + current_encoder_out = current_encoder_out.unsqueeze(1).unsqueeze(1) + # current_encoder_out's shape is (batch_size, 1, 1, encoder_out_dim) + offset = end + + finalized_B = B[batch_size:] + finalized_B + B = B[:batch_size] + + hyps_shape = get_hyps_shape(B).to(device) + + A = [list(b) for b in B] + B = [HypothesisList() for _ in range(batch_size)] + + ys_log_probs = torch.cat( + [hyp.log_prob.reshape(1, 1) for hyps in A for hyp in hyps] + ) + + decoder_input = torch.tensor( + [hyp.ys[-context_size:] for hyps in A for hyp in hyps], + device=device, + dtype=torch.int64, + ) # (num_hyps, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False).unsqueeze(1) + decoder_out = model.joiner.decoder_proj(decoder_out) + + current_encoder_out = torch.index_select( + current_encoder_out, + dim=0, + index=hyps_shape.row_ids(1).to(torch.int64), + ) # (num_hyps, 1, 1, encoder_out_dim) + + logits = model.joiner( + current_encoder_out, + decoder_out, + project_input=False, + ) # (num_hyps, 1, 1, vocab_size) + + logits = logits.squeeze(1).squeeze(1) # (num_hyps, vocab_size) + + log_probs = logits.log_softmax(dim=-1) # (num_hyps, vocab_size) + + log_probs.add_(ys_log_probs) + + vocab_size = log_probs.size(-1) + + log_probs = log_probs.reshape(-1) + + row_splits = hyps_shape.row_splits(1) * vocab_size + log_probs_shape = k2.ragged.create_ragged_shape2( + row_splits=row_splits, cached_tot_size=log_probs.numel() + ) + ragged_log_probs = k2.RaggedTensor(shape=log_probs_shape, value=log_probs) + """ + for all hyps with a non-blank new token, score this token. + It is a little confusing here because this for-loop + looks very similar to the one below. Here, we go through all + top-k tokens and only add the non-blanks ones to the token_list. + The RNNLM will score those tokens given the LM states. Note that + the variable `scores` is the LM score after seeing the new + non-blank token. + """ + token_list = [] + hs = [] + cs = [] + for i in range(batch_size): + topk_log_probs, topk_indexes = ragged_log_probs[i].topk(beam) + + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + topk_hyp_indexes = (topk_indexes // vocab_size).tolist() + topk_token_indexes = (topk_indexes % vocab_size).tolist() + for k in range(len(topk_hyp_indexes)): + hyp_idx = topk_hyp_indexes[k] + hyp = A[i][hyp_idx] + + new_token = topk_token_indexes[k] + if new_token not in (blank_id, unk_id): + assert new_token != 0, new_token + token_list.append([new_token]) + # store the LSTM states + hs.append(hyp.state[0]) + cs.append(hyp.state[1]) + + # forward RNNLM to get new states and scores + if len(token_list) != 0: + tokens_to_score = ( + torch.tensor(token_list).to(torch.int64).to(device).reshape(-1, 1) + ) + + hs = torch.cat(hs, dim=1).to(device) + cs = torch.cat(cs, dim=1).to(device) + scores, lm_states = rnnlm.score_token(tokens_to_score, (hs, cs)) + + count = 0 # index, used to locate score and lm states + for i in range(batch_size): + topk_log_probs, topk_indexes = ragged_log_probs[i].topk(beam) + + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + topk_hyp_indexes = (topk_indexes // vocab_size).tolist() + topk_token_indexes = (topk_indexes % vocab_size).tolist() + + for k in range(len(topk_hyp_indexes)): + hyp_idx = topk_hyp_indexes[k] + hyp = A[i][hyp_idx] + + ys = hyp.ys[:] + + # current score of hyp + lm_score = hyp.lm_score + state = hyp.state + + hyp_log_prob = topk_log_probs[k] # get score of current hyp + new_token = topk_token_indexes[k] + if new_token not in (blank_id, unk_id): + + ys.append(new_token) + state_cost = hyp.state_cost.forward_one_step(new_token) + + # calculate the score of the latest token + current_ngram_score = state_cost.lm_score - hyp.state_cost.lm_score + + assert current_ngram_score <= 0.0, ( + state_cost.lm_score, + hyp.state_cost.lm_score, + ) + # score = score + RNNLM_score - LODR_score + # LODR_LM_scale is a negative number here + hyp_log_prob += ( + lm_score[new_token] * lm_scale + + LODR_lm_scale * current_ngram_score + ) # add the lm score + + lm_score = scores[count] + state = ( + lm_states[0][:, count, :].unsqueeze(1), + lm_states[1][:, count, :].unsqueeze(1), + ) + count += 1 + else: + state_cost = hyp.state_cost + + new_hyp = Hypothesis( + ys=ys, + log_prob=hyp_log_prob, + state=state, + lm_score=lm_score, + state_cost=state_cost, + ) + B[i].add(new_hyp) + + B = B + finalized_B + best_hyps = [b.get_most_probable(length_norm=True) for b in B] + + sorted_ans = [h.ys[context_size:] for h in best_hyps] + ans = [] + unsorted_indices = packed_encoder_out.unsorted_indices.tolist() + for i in range(N): + ans.append(sorted_ans[unsorted_indices[i]]) + + return ans diff --git a/egs/librispeech/ASR/incremental_transf/conformer.py b/egs/librispeech/ASR/incremental_transf/conformer.py new file mode 100644 index 000000000..9e12bbeaa --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/conformer.py @@ -0,0 +1,1809 @@ +#!/usr/bin/env python3 +# Copyright (c) 2021 University of Chinese Academy of Sciences (author: Han Zhu) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import copy +import math +import warnings +from typing import List, Optional, Tuple + +import torch +from encoder_interface import EncoderInterface +from scaling import ( + ActivationBalancer, + BasicNorm, + DoubleSwish, + ScaledConv1d, + ScaledConv2d, + ScaledLinear, +) +from torch import Tensor, nn + +from icefall.utils import make_pad_mask, subsequent_chunk_mask + + +class Conformer(EncoderInterface): + """ + Args: + num_features (int): Number of input features + subsampling_factor (int): subsampling factor of encoder (the convolution layers before transformers) + d_model (int): attention dimension, also the output dimension + nhead (int): number of head + dim_feedforward (int): feedforward dimention + num_encoder_layers (int): number of encoder layers + dropout (float): dropout rate + layer_dropout (float): layer-dropout rate. + cnn_module_kernel (int): Kernel size of convolution module. + dynamic_chunk_training (bool): whether to use dynamic chunk training, if + you want to train a streaming model, this is expected to be True. + When setting True, it will use a masking strategy to make the attention + see only limited left and right context. + short_chunk_threshold (float): a threshold to determinize the chunk size + to be used in masking training, if the randomly generated chunk size + is greater than ``max_len * short_chunk_threshold`` (max_len is the + max sequence length of current batch) then it will use + full context in training (i.e. with chunk size equals to max_len). + This will be used only when dynamic_chunk_training is True. + short_chunk_size (int): see docs above, if the randomly generated chunk + size equals to or less than ``max_len * short_chunk_threshold``, the + chunk size will be sampled uniformly from 1 to short_chunk_size. + This also will be used only when dynamic_chunk_training is True. + num_left_chunks (int): the left context (in chunks) attention can see, the + chunk size is decided by short_chunk_threshold and short_chunk_size. + A minus value means seeing full left context. + This also will be used only when dynamic_chunk_training is True. + causal (bool): Whether to use causal convolution in conformer encoder + layer. This MUST be True when using dynamic_chunk_training. + """ + + def __init__( + self, + num_features: int, + subsampling_factor: int = 4, + d_model: int = 256, + nhead: int = 4, + dim_feedforward: int = 2048, + num_encoder_layers: int = 12, + dropout: float = 0.1, + layer_dropout: float = 0.075, + cnn_module_kernel: int = 31, + aux_layer_period: int = 3, + dynamic_chunk_training: bool = False, + short_chunk_threshold: float = 0.75, + short_chunk_size: int = 25, + num_left_chunks: int = -1, + causal: bool = False, + ) -> None: + super(Conformer, self).__init__() + + self.num_features = num_features + self.subsampling_factor = subsampling_factor + if subsampling_factor != 4: + raise NotImplementedError("Support only 'subsampling_factor=4'.") + + # self.encoder_embed converts the input of shape (N, T, num_features) + # to the shape (N, T//subsampling_factor, d_model). + # That is, it does two things simultaneously: + # (1) subsampling: T -> T//subsampling_factor + # (2) embedding: num_features -> d_model + self.encoder_embed = Conv2dSubsampling(num_features, d_model) + + self.encoder_pos = RelPositionalEncoding(d_model, dropout) + + self.encoder_layers = num_encoder_layers + self.d_model = d_model + self.cnn_module_kernel = cnn_module_kernel + self.causal = causal + self.dynamic_chunk_training = dynamic_chunk_training + self.short_chunk_threshold = short_chunk_threshold + self.short_chunk_size = short_chunk_size + self.num_left_chunks = num_left_chunks + + encoder_layer = ConformerEncoderLayer( + d_model=d_model, + nhead=nhead, + dim_feedforward=dim_feedforward, + dropout=dropout, + layer_dropout=layer_dropout, + cnn_module_kernel=cnn_module_kernel, + causal=causal, + ) + # aux_layers from 1/3 + self.encoder = ConformerEncoder( + encoder_layer=encoder_layer, + num_layers=num_encoder_layers, + aux_layers=list( + range( + num_encoder_layers // 3, + num_encoder_layers - 1, + aux_layer_period, + ) + ), + ) + self._init_state: List[torch.Tensor] = [torch.empty(0)] + + def forward( + self, x: torch.Tensor, x_lens: torch.Tensor, warmup: float = 1.0 + ) -> Tuple[torch.Tensor, torch.Tensor]: + """ + Args: + x: + The input tensor. Its shape is (batch_size, seq_len, feature_dim). + x_lens: + A tensor of shape (batch_size,) containing the number of frames in + `x` before padding. + warmup: + A floating point value that gradually increases from 0 throughout + training; when it is >= 1.0 we are "fully warmed up". It is used + to turn modules on sequentially. + Returns: + Return a tuple containing 2 tensors: + - embeddings: its shape is (batch_size, output_seq_len, d_model) + - lengths, a tensor of shape (batch_size,) containing the number + of frames in `embeddings` before padding. + """ + x = self.encoder_embed(x) + x, pos_emb = self.encoder_pos(x) + x = x.permute(1, 0, 2) # (N, T, C) -> (T, N, C) + + lengths = (((x_lens - 1) >> 1) - 1) >> 1 + assert x.size(0) == lengths.max().item() + src_key_padding_mask = make_pad_mask(lengths) + + if self.dynamic_chunk_training: + assert ( + self.causal + ), "Causal convolution is required for streaming conformer." + max_len = x.size(0) + chunk_size = torch.randint(1, max_len, (1,)).item() + if chunk_size > (max_len * self.short_chunk_threshold): + chunk_size = max_len + else: + chunk_size = chunk_size % self.short_chunk_size + 1 + + mask = ~subsequent_chunk_mask( + size=x.size(0), + chunk_size=chunk_size, + num_left_chunks=self.num_left_chunks, + device=x.device, + ) + x = self.encoder( + x, + pos_emb, + mask=mask, + src_key_padding_mask=src_key_padding_mask, + warmup=warmup, + ) # (T, N, C) + else: + x = self.encoder( + x, + pos_emb, + src_key_padding_mask=src_key_padding_mask, + warmup=warmup, + ) # (T, N, C) + + x = x.permute(1, 0, 2) # (T, N, C) ->(N, T, C) + + return x, lengths + + @torch.jit.export + def get_init_state( + self, left_context: int, device: torch.device + ) -> List[torch.Tensor]: + """Return the initial cache state of the model. + Args: + left_context: The left context size (in frames after subsampling). + Returns: + Return the initial state of the model, it is a list containing two + tensors, the first one is the cache for attentions which has a shape + of (num_encoder_layers, left_context, encoder_dim), the second one + is the cache of conv_modules which has a shape of + (num_encoder_layers, cnn_module_kernel - 1, encoder_dim). + NOTE: the returned tensors are on the given device. + """ + if len(self._init_state) == 2 and self._init_state[0].size(1) == left_context: + # Note: It is OK to share the init state as it is + # not going to be modified by the model + return self._init_state + + init_states: List[torch.Tensor] = [ + torch.zeros( + ( + self.encoder_layers, + left_context, + self.d_model, + ), + device=device, + ), + torch.zeros( + ( + self.encoder_layers, + self.cnn_module_kernel - 1, + self.d_model, + ), + device=device, + ), + ] + + self._init_state = init_states + + return init_states + + @torch.jit.export + def streaming_forward( + self, + x: torch.Tensor, + x_lens: torch.Tensor, + states: Optional[List[Tensor]] = None, + processed_lens: Optional[Tensor] = None, + left_context: int = 64, + right_context: int = 4, + chunk_size: int = 16, + simulate_streaming: bool = False, + warmup: float = 1.0, + ) -> Tuple[torch.Tensor, torch.Tensor, List[torch.Tensor]]: + """ + Args: + x: + The input tensor. Its shape is (batch_size, seq_len, feature_dim). + x_lens: + A tensor of shape (batch_size,) containing the number of frames in + `x` before padding. + states: + The decode states for previous frames which contains the cached data. + It has two elements, the first element is the attn_cache which has + a shape of (encoder_layers, left_context, batch, attention_dim), + the second element is the conv_cache which has a shape of + (encoder_layers, cnn_module_kernel-1, batch, conv_dim). + Note: states will be modified in this function. + processed_lens: + How many frames (after subsampling) have been processed for each sequence. + left_context: + How many previous frames the attention can see in current chunk. + Note: It's not that each individual frame has `left_context` frames + of left context, some have more. + right_context: + How many future frames the attention can see in current chunk. + Note: It's not that each individual frame has `right_context` frames + of right context, some have more. + chunk_size: + The chunk size for decoding, this will be used to simulate streaming + decoding using masking. + simulate_streaming: + If setting True, it will use a masking strategy to simulate streaming + fashion (i.e. every chunk data only see limited left context and + right context). The whole sequence is supposed to be send at a time + When using simulate_streaming. + warmup: + A floating point value that gradually increases from 0 throughout + training; when it is >= 1.0 we are "fully warmed up". It is used + to turn modules on sequentially. + Returns: + Return a tuple containing 2 tensors: + - logits, its shape is (batch_size, output_seq_len, output_dim) + - logit_lens, a tensor of shape (batch_size,) containing the number + of frames in `logits` before padding. + - decode_states, the updated states including the information + of current chunk. + """ + + # x: [N, T, C] + # Caution: We assume the subsampling factor is 4! + + # lengths = ((x_lens - 1) // 2 - 1) // 2 # issue an warning + # + # Note: rounding_mode in torch.div() is available only in torch >= 1.8.0 + lengths = (((x_lens - 1) >> 1) - 1) >> 1 + + if not simulate_streaming: + assert states is not None + assert processed_lens is not None + assert ( + len(states) == 2 + and states[0].shape + == (self.encoder_layers, left_context, x.size(0), self.d_model) + and states[1].shape + == ( + self.encoder_layers, + self.cnn_module_kernel - 1, + x.size(0), + self.d_model, + ) + ), f"""The length of states MUST be equal to 2, and the shape of + first element should be {(self.encoder_layers, left_context, x.size(0), self.d_model)}, + given {states[0].shape}. the shape of second element should be + {(self.encoder_layers, self.cnn_module_kernel - 1, x.size(0), self.d_model)}, + given {states[1].shape}.""" + + lengths -= 2 # we will cut off 1 frame on each side of encoder_embed output + + src_key_padding_mask = make_pad_mask(lengths) + + processed_mask = torch.arange(left_context, device=x.device).expand( + x.size(0), left_context + ) + processed_lens = processed_lens.view(x.size(0), 1) + processed_mask = (processed_lens <= processed_mask).flip(1) + + src_key_padding_mask = torch.cat( + [processed_mask, src_key_padding_mask], dim=1 + ) + + embed = self.encoder_embed(x) + + # cut off 1 frame on each size of embed as they see the padding + # value which causes a training and decoding mismatch. + embed = embed[:, 1:-1, :] + + embed, pos_enc = self.encoder_pos(embed, left_context) + embed = embed.permute(1, 0, 2) # (B, T, F) -> (T, B, F) + + x, states = self.encoder.chunk_forward( + embed, + pos_enc, + src_key_padding_mask=src_key_padding_mask, + warmup=warmup, + states=states, + left_context=left_context, + right_context=right_context, + ) # (T, B, F) + if right_context > 0: + x = x[0:-right_context, ...] + lengths -= right_context + else: + assert states is None + states = [] # just to make torch.script.jit happy + # this branch simulates streaming decoding using mask as we are + # using in training time. + src_key_padding_mask = make_pad_mask(lengths) + x = self.encoder_embed(x) + x, pos_emb = self.encoder_pos(x) + x = x.permute(1, 0, 2) # (N, T, C) -> (T, N, C) + + assert x.size(0) == lengths.max().item() + + num_left_chunks = -1 + if left_context >= 0: + assert left_context % chunk_size == 0 + num_left_chunks = left_context // chunk_size + + mask = ~subsequent_chunk_mask( + size=x.size(0), + chunk_size=chunk_size, + num_left_chunks=num_left_chunks, + device=x.device, + ) + x = self.encoder( + x, + pos_emb, + mask=mask, + src_key_padding_mask=src_key_padding_mask, + warmup=warmup, + ) # (T, N, C) + + x = x.permute(1, 0, 2) # (T, N, C) ->(N, T, C) + + return x, lengths, states + + +class ConformerEncoderLayer(nn.Module): + """ + ConformerEncoderLayer is made up of self-attn, feedforward and convolution networks. + See: "Conformer: Convolution-augmented Transformer for Speech Recognition" + + Args: + d_model: the number of expected features in the input (required). + nhead: the number of heads in the multiheadattention models (required). + dim_feedforward: the dimension of the feedforward network model (default=2048). + dropout: the dropout value (default=0.1). + cnn_module_kernel (int): Kernel size of convolution module. + causal (bool): Whether to use causal convolution in conformer encoder + layer. This MUST be True when using dynamic_chunk_training and streaming decoding. + + Examples:: + >>> encoder_layer = ConformerEncoderLayer(d_model=512, nhead=8) + >>> src = torch.rand(10, 32, 512) + >>> pos_emb = torch.rand(32, 19, 512) + >>> out = encoder_layer(src, pos_emb) + """ + + def __init__( + self, + d_model: int, + nhead: int, + dim_feedforward: int = 2048, + dropout: float = 0.1, + layer_dropout: float = 0.075, + cnn_module_kernel: int = 31, + causal: bool = False, + ) -> None: + super(ConformerEncoderLayer, self).__init__() + + self.layer_dropout = layer_dropout + + self.d_model = d_model + + self.self_attn = RelPositionMultiheadAttention(d_model, nhead, dropout=0.0) + + self.feed_forward = nn.Sequential( + ScaledLinear(d_model, dim_feedforward), + ActivationBalancer(channel_dim=-1), + DoubleSwish(), + nn.Dropout(dropout), + ScaledLinear(dim_feedforward, d_model, initial_scale=0.25), + ) + + self.feed_forward_macaron = nn.Sequential( + ScaledLinear(d_model, dim_feedforward), + ActivationBalancer(channel_dim=-1), + DoubleSwish(), + nn.Dropout(dropout), + ScaledLinear(dim_feedforward, d_model, initial_scale=0.25), + ) + + self.conv_module = ConvolutionModule(d_model, cnn_module_kernel, causal=causal) + + self.norm_final = BasicNorm(d_model) + + # try to ensure the output is close to zero-mean (or at least, zero-median). + self.balancer = ActivationBalancer( + channel_dim=-1, min_positive=0.45, max_positive=0.55, max_abs=6.0 + ) + + self.dropout = nn.Dropout(dropout) + + def forward( + self, + src: Tensor, + pos_emb: Tensor, + src_mask: Optional[Tensor] = None, + src_key_padding_mask: Optional[Tensor] = None, + warmup: float = 1.0, + ) -> Tensor: + """ + Pass the input through the encoder layer. + + Args: + src: the sequence to the encoder layer (required). + pos_emb: Positional embedding tensor (required). + src_mask: the mask for the src sequence (optional). + src_key_padding_mask: the mask for the src keys per batch (optional). + warmup: controls selective bypass of of layers; if < 1.0, we will + bypass layers more frequently. + + Shape: + src: (S, N, E). + pos_emb: (N, 2*S-1, E) + src_mask: (S, S). + src_key_padding_mask: (N, S). + S is the source sequence length, N is the batch size, E is the feature number + """ + src_orig = src + + warmup_scale = min(0.1 + warmup, 1.0) + # alpha = 1.0 means fully use this encoder layer, 0.0 would mean + # completely bypass it. + if self.training: + alpha = ( + warmup_scale + if torch.rand(()).item() <= (1.0 - self.layer_dropout) + else 0.1 + ) + else: + alpha = 1.0 + + # macaron style feed forward module + src = src + self.dropout(self.feed_forward_macaron(src)) + + # multi-headed self-attention module + src_att = self.self_attn( + src, + src, + src, + pos_emb=pos_emb, + attn_mask=src_mask, + key_padding_mask=src_key_padding_mask, + )[0] + src = src + self.dropout(src_att) + + # convolution module + conv, _ = self.conv_module(src, src_key_padding_mask=src_key_padding_mask) + src = src + self.dropout(conv) + + # feed forward module + src = src + self.dropout(self.feed_forward(src)) + + src = self.norm_final(self.balancer(src)) + + if alpha != 1.0: + src = alpha * src + (1 - alpha) * src_orig + + return src + + @torch.jit.export + def chunk_forward( + self, + src: Tensor, + pos_emb: Tensor, + states: List[Tensor], + src_mask: Optional[Tensor] = None, + src_key_padding_mask: Optional[Tensor] = None, + warmup: float = 1.0, + left_context: int = 0, + right_context: int = 0, + ) -> Tuple[Tensor, List[Tensor]]: + """ + Pass the input through the encoder layer. + Args: + src: the sequence to the encoder layer (required). + pos_emb: Positional embedding tensor (required). + states: + The decode states for previous frames which contains the cached data. + It has two elements, the first element is the attn_cache which has + a shape of (left_context, batch, attention_dim), + the second element is the conv_cache which has a shape of + (cnn_module_kernel-1, batch, conv_dim). + Note: states will be modified in this function. + src_mask: the mask for the src sequence (optional). + src_key_padding_mask: the mask for the src keys per batch (optional). + warmup: controls selective bypass of of layers; if < 1.0, we will + bypass layers more frequently. + left_context: + How many previous frames the attention can see in current chunk. + Note: It's not that each individual frame has `left_context` frames + of left context, some have more. + right_context: + How many future frames the attention can see in current chunk. + Note: It's not that each individual frame has `right_context` frames + of right context, some have more. + Shape: + src: (S, N, E). + pos_emb: (N, 2*(S+left_context)-1, E). + src_mask: (S, S). + src_key_padding_mask: (N, S). + S is the source sequence length, N is the batch size, E is the feature number + """ + + assert not self.training + assert len(states) == 2 + assert states[0].shape == (left_context, src.size(1), src.size(2)) + + # macaron style feed forward module + src = src + self.dropout(self.feed_forward_macaron(src)) + + # We put the attention cache this level (i.e. before linear transformation) + # to save memory consumption, when decoding in streaming fashion, the + # batch size would be thousands (for 32GB machine), if we cache key & val + # separately, it needs extra several GB memory. + # TODO(WeiKang): Move cache to self_attn level (i.e. cache key & val + # separately) if needed. + key = torch.cat([states[0], src], dim=0) + val = key + if right_context > 0: + states[0] = key[ + -(left_context + right_context) : -right_context, ... # noqa + ] + else: + states[0] = key[-left_context:, ...] + + # multi-headed self-attention module + src_att = self.self_attn( + src, + key, + val, + pos_emb=pos_emb, + attn_mask=src_mask, + key_padding_mask=src_key_padding_mask, + left_context=left_context, + )[0] + + src = src + self.dropout(src_att) + + # convolution module + conv, conv_cache = self.conv_module(src, states[1], right_context) + states[1] = conv_cache + + src = src + self.dropout(conv) + + # feed forward module + src = src + self.dropout(self.feed_forward(src)) + + src = self.norm_final(self.balancer(src)) + + return src, states + + +class ConformerEncoder(nn.Module): + r"""ConformerEncoder is a stack of N encoder layers + + Args: + encoder_layer: an instance of the ConformerEncoderLayer() class (required). + num_layers: the number of sub-encoder-layers in the encoder (required). + + Examples:: + >>> encoder_layer = ConformerEncoderLayer(d_model=512, nhead=8) + >>> conformer_encoder = ConformerEncoder(encoder_layer, num_layers=6) + >>> src = torch.rand(10, 32, 512) + >>> pos_emb = torch.rand(32, 19, 512) + >>> out = conformer_encoder(src, pos_emb) + """ + + def __init__( + self, + encoder_layer: nn.Module, + num_layers: int, + aux_layers: List[int], + ) -> None: + super().__init__() + self.layers = nn.ModuleList( + [copy.deepcopy(encoder_layer) for i in range(num_layers)] + ) + self.num_layers = num_layers + + assert len(set(aux_layers)) == len(aux_layers) + + assert num_layers - 1 not in aux_layers + self.aux_layers = aux_layers + [num_layers - 1] + + self.combiner = RandomCombine( + num_inputs=len(self.aux_layers), + final_weight=0.5, + pure_prob=0.333, + stddev=2.0, + ) + + def forward( + self, + src: Tensor, + pos_emb: Tensor, + mask: Optional[Tensor] = None, + src_key_padding_mask: Optional[Tensor] = None, + warmup: float = 1.0, + ) -> Tensor: + r"""Pass the input through the encoder layers in turn. + + Args: + src: the sequence to the encoder (required). + pos_emb: Positional embedding tensor (required). + mask: the mask for the src sequence (optional). + src_key_padding_mask: the mask for the src keys per batch (optional). + + Shape: + src: (S, N, E). + pos_emb: (N, 2*S-1, E) + mask: (S, S). + src_key_padding_mask: (N, S). + S is the source sequence length, T is the target sequence length, N is the batch size, E is the feature number + + """ + output = src + + outputs = [] + + for i, mod in enumerate(self.layers): + output = mod( + output, + pos_emb, + src_mask=mask, + src_key_padding_mask=src_key_padding_mask, + warmup=warmup, + ) + if i in self.aux_layers: + outputs.append(output) + + output = self.combiner(outputs) + + return output + + @torch.jit.export + def chunk_forward( + self, + src: Tensor, + pos_emb: Tensor, + states: List[Tensor], + mask: Optional[Tensor] = None, + src_key_padding_mask: Optional[Tensor] = None, + warmup: float = 1.0, + left_context: int = 0, + right_context: int = 0, + ) -> Tuple[Tensor, List[Tensor]]: + r"""Pass the input through the encoder layers in turn. + Args: + src: the sequence to the encoder (required). + pos_emb: Positional embedding tensor (required). + states: + The decode states for previous frames which contains the cached data. + It has two elements, the first element is the attn_cache which has + a shape of (encoder_layers, left_context, batch, attention_dim), + the second element is the conv_cache which has a shape of + (encoder_layers, cnn_module_kernel-1, batch, conv_dim). + Note: states will be modified in this function. + mask: the mask for the src sequence (optional). + src_key_padding_mask: the mask for the src keys per batch (optional). + warmup: controls selective bypass of of layers; if < 1.0, we will + bypass layers more frequently. + left_context: + How many previous frames the attention can see in current chunk. + Note: It's not that each individual frame has `left_context` frames + of left context, some have more. + right_context: + How many future frames the attention can see in current chunk. + Note: It's not that each individual frame has `right_context` frames + of right context, some have more. + Shape: + src: (S, N, E). + pos_emb: (N, 2*(S+left_context)-1, E). + mask: (S, S). + src_key_padding_mask: (N, S). + S is the source sequence length, T is the target sequence length, N is the batch size, E is the feature number + """ + assert not self.training + assert len(states) == 2 + assert states[0].shape == ( + self.num_layers, + left_context, + src.size(1), + src.size(2), + ) + assert states[1].size(0) == self.num_layers + + output = src + + for layer_index, mod in enumerate(self.layers): + cache = [states[0][layer_index], states[1][layer_index]] + output, cache = mod.chunk_forward( + output, + pos_emb, + states=cache, + src_mask=mask, + src_key_padding_mask=src_key_padding_mask, + warmup=warmup, + left_context=left_context, + right_context=right_context, + ) + states[0][layer_index] = cache[0] + states[1][layer_index] = cache[1] + + return output, states + + +class RelPositionalEncoding(torch.nn.Module): + """Relative positional encoding module. + + See : Appendix B in "Transformer-XL: Attentive Language Models Beyond a Fixed-Length Context" + Modified from https://github.com/espnet/espnet/blob/master/espnet/nets/pytorch_backend/transformer/embedding.py + + Args: + d_model: Embedding dimension. + dropout_rate: Dropout rate. + max_len: Maximum input length. + + """ + + def __init__(self, d_model: int, dropout_rate: float, max_len: int = 5000) -> None: + """Construct an PositionalEncoding object.""" + super(RelPositionalEncoding, self).__init__() + self.d_model = d_model + self.dropout = torch.nn.Dropout(p=dropout_rate) + self.pe = None + self.extend_pe(torch.tensor(0.0).expand(1, max_len)) + + def extend_pe(self, x: Tensor, left_context: int = 0) -> None: + """Reset the positional encodings.""" + x_size_1 = x.size(1) + left_context + if self.pe is not None: + # self.pe contains both positive and negative parts + # the length of self.pe is 2 * input_len - 1 + if self.pe.size(1) >= x_size_1 * 2 - 1: + # Note: TorchScript doesn't implement operator== for torch.Device + if self.pe.dtype != x.dtype or str(self.pe.device) != str(x.device): + self.pe = self.pe.to(dtype=x.dtype, device=x.device) + return + # Suppose `i` means to the position of query vector and `j` means the + # position of key vector. We use position relative positions when keys + # are to the left (i>j) and negative relative positions otherwise (i Tuple[Tensor, Tensor]: + """Add positional encoding. + + Args: + x (torch.Tensor): Input tensor (batch, time, `*`). + left_context (int): left context (in frames) used during streaming decoding. + this is used only in real streaming decoding, in other circumstances, + it MUST be 0. + + Returns: + torch.Tensor: Encoded tensor (batch, time, `*`). + torch.Tensor: Encoded tensor (batch, 2*time-1, `*`). + + """ + self.extend_pe(x, left_context) + x_size_1 = x.size(1) + left_context + pos_emb = self.pe[ + :, + self.pe.size(1) // 2 + - x_size_1 + + 1 : self.pe.size(1) // 2 # noqa E203 + + x.size(1), + ] + return self.dropout(x), self.dropout(pos_emb) + + +class RelPositionMultiheadAttention(nn.Module): + r"""Multi-Head Attention layer with relative position encoding + + See reference: "Transformer-XL: Attentive Language Models Beyond a Fixed-Length Context" + + Args: + embed_dim: total dimension of the model. + num_heads: parallel attention heads. + dropout: a Dropout layer on attn_output_weights. Default: 0.0. + + Examples:: + + >>> rel_pos_multihead_attn = RelPositionMultiheadAttention(embed_dim, num_heads) + >>> attn_output, attn_output_weights = multihead_attn(query, key, value, pos_emb) + """ + + def __init__( + self, + embed_dim: int, + num_heads: int, + dropout: float = 0.0, + ) -> None: + super(RelPositionMultiheadAttention, self).__init__() + self.embed_dim = embed_dim + self.num_heads = num_heads + self.dropout = dropout + self.head_dim = embed_dim // num_heads + assert ( + self.head_dim * num_heads == self.embed_dim + ), "embed_dim must be divisible by num_heads" + + self.in_proj = ScaledLinear(embed_dim, 3 * embed_dim, bias=True) + self.out_proj = ScaledLinear( + embed_dim, embed_dim, bias=True, initial_scale=0.25 + ) + + # linear transformation for positional encoding. + self.linear_pos = ScaledLinear(embed_dim, embed_dim, bias=False) + # these two learnable bias are used in matrix c and matrix d + # as described in "Transformer-XL: Attentive Language Models Beyond a Fixed-Length Context" Section 3.3 + self.pos_bias_u = nn.Parameter(torch.Tensor(num_heads, self.head_dim)) + self.pos_bias_v = nn.Parameter(torch.Tensor(num_heads, self.head_dim)) + self.pos_bias_u_scale = nn.Parameter(torch.zeros(()).detach()) + self.pos_bias_v_scale = nn.Parameter(torch.zeros(()).detach()) + self._reset_parameters() + + def _pos_bias_u(self): + return self.pos_bias_u * self.pos_bias_u_scale.exp() + + def _pos_bias_v(self): + return self.pos_bias_v * self.pos_bias_v_scale.exp() + + def _reset_parameters(self) -> None: + nn.init.normal_(self.pos_bias_u, std=0.01) + nn.init.normal_(self.pos_bias_v, std=0.01) + + def forward( + self, + query: Tensor, + key: Tensor, + value: Tensor, + pos_emb: Tensor, + key_padding_mask: Optional[Tensor] = None, + need_weights: bool = True, + attn_mask: Optional[Tensor] = None, + left_context: int = 0, + ) -> Tuple[Tensor, Optional[Tensor]]: + r""" + Args: + query, key, value: map a query and a set of key-value pairs to an output. + pos_emb: Positional embedding tensor + key_padding_mask: if provided, specified padding elements in the key will + be ignored by the attention. When given a binary mask and a value is True, + the corresponding value on the attention layer will be ignored. When given + a byte mask and a value is non-zero, the corresponding value on the attention + layer will be ignored + need_weights: output attn_output_weights. + attn_mask: 2D or 3D mask that prevents attention to certain positions. A 2D mask will be broadcasted for all + the batches while a 3D mask allows to specify a different mask for the entries of each batch. + left_context (int): left context (in frames) used during streaming decoding. + this is used only in real streaming decoding, in other circumstances, + it MUST be 0. + + Shape: + - Inputs: + - query: :math:`(L, N, E)` where L is the target sequence length, N is the batch size, E is + the embedding dimension. + - key: :math:`(S, N, E)`, where S is the source sequence length, N is the batch size, E is + the embedding dimension. + - value: :math:`(S, N, E)` where S is the source sequence length, N is the batch size, E is + the embedding dimension. + - pos_emb: :math:`(N, 2*L-1, E)` where L is the target sequence length, N is the batch size, E is + the embedding dimension. + - key_padding_mask: :math:`(N, S)` where N is the batch size, S is the source sequence length. + If a ByteTensor is provided, the non-zero positions will be ignored while the position + with the zero positions will be unchanged. If a BoolTensor is provided, the positions with the + value of ``True`` will be ignored while the position with the value of ``False`` will be unchanged. + - attn_mask: 2D mask :math:`(L, S)` where L is the target sequence length, S is the source sequence length. + 3D mask :math:`(N*num_heads, L, S)` where N is the batch size, L is the target sequence length, + S is the source sequence length. attn_mask ensure that position i is allowed to attend the unmasked + positions. If a ByteTensor is provided, the non-zero positions are not allowed to attend + while the zero positions will be unchanged. If a BoolTensor is provided, positions with ``True`` + is not allowed to attend while ``False`` values will be unchanged. If a FloatTensor + is provided, it will be added to the attention weight. + + - Outputs: + - attn_output: :math:`(L, N, E)` where L is the target sequence length, N is the batch size, + E is the embedding dimension. + - attn_output_weights: :math:`(N, L, S)` where N is the batch size, + L is the target sequence length, S is the source sequence length. + """ + return self.multi_head_attention_forward( + query, + key, + value, + pos_emb, + self.embed_dim, + self.num_heads, + self.in_proj.get_weight(), + self.in_proj.get_bias(), + self.dropout, + self.out_proj.get_weight(), + self.out_proj.get_bias(), + training=self.training, + key_padding_mask=key_padding_mask, + need_weights=need_weights, + attn_mask=attn_mask, + left_context=left_context, + ) + + def rel_shift(self, x: Tensor, left_context: int = 0) -> Tensor: + """Compute relative positional encoding. + + Args: + x: Input tensor (batch, head, time1, 2*time1-1). + time1 means the length of query vector. + left_context (int): left context (in frames) used during streaming decoding. + this is used only in real streaming decoding, in other circumstances, + it MUST be 0. + + Returns: + Tensor: tensor of shape (batch, head, time1, time2) + (note: time2 has the same value as time1, but it is for + the key, while time1 is for the query). + """ + (batch_size, num_heads, time1, n) = x.shape + time2 = time1 + left_context + assert ( + n == left_context + 2 * time1 - 1 + ), f"{n} == {left_context} + 2 * {time1} - 1" + # Note: TorchScript requires explicit arg for stride() + batch_stride = x.stride(0) + head_stride = x.stride(1) + time1_stride = x.stride(2) + n_stride = x.stride(3) + return x.as_strided( + (batch_size, num_heads, time1, time2), + (batch_stride, head_stride, time1_stride - n_stride, n_stride), + storage_offset=n_stride * (time1 - 1), + ) + + def multi_head_attention_forward( + self, + query: Tensor, + key: Tensor, + value: Tensor, + pos_emb: Tensor, + embed_dim_to_check: int, + num_heads: int, + in_proj_weight: Tensor, + in_proj_bias: Tensor, + dropout_p: float, + out_proj_weight: Tensor, + out_proj_bias: Tensor, + training: bool = True, + key_padding_mask: Optional[Tensor] = None, + need_weights: bool = True, + attn_mask: Optional[Tensor] = None, + left_context: int = 0, + ) -> Tuple[Tensor, Optional[Tensor]]: + r""" + Args: + query, key, value: map a query and a set of key-value pairs to an output. + pos_emb: Positional embedding tensor + embed_dim_to_check: total dimension of the model. + num_heads: parallel attention heads. + in_proj_weight, in_proj_bias: input projection weight and bias. + dropout_p: probability of an element to be zeroed. + out_proj_weight, out_proj_bias: the output projection weight and bias. + training: apply dropout if is ``True``. + key_padding_mask: if provided, specified padding elements in the key will + be ignored by the attention. This is an binary mask. When the value is True, + the corresponding value on the attention layer will be filled with -inf. + need_weights: output attn_output_weights. + attn_mask: 2D or 3D mask that prevents attention to certain positions. A 2D mask will be broadcasted for all + the batches while a 3D mask allows to specify a different mask for the entries of each batch. + left_context (int): left context (in frames) used during streaming decoding. + this is used only in real streaming decoding, in other circumstances, + it MUST be 0. + + Shape: + Inputs: + - query: :math:`(L, N, E)` where L is the target sequence length, N is the batch size, E is + the embedding dimension. + - key: :math:`(S, N, E)`, where S is the source sequence length, N is the batch size, E is + the embedding dimension. + - value: :math:`(S, N, E)` where S is the source sequence length, N is the batch size, E is + the embedding dimension. + - pos_emb: :math:`(N, 2*L-1, E)` or :math:`(1, 2*L-1, E)` where L is the target sequence + length, N is the batch size, E is the embedding dimension. + - key_padding_mask: :math:`(N, S)` where N is the batch size, S is the source sequence length. + If a ByteTensor is provided, the non-zero positions will be ignored while the zero positions + will be unchanged. If a BoolTensor is provided, the positions with the + value of ``True`` will be ignored while the position with the value of ``False`` will be unchanged. + - attn_mask: 2D mask :math:`(L, S)` where L is the target sequence length, S is the source sequence length. + 3D mask :math:`(N*num_heads, L, S)` where N is the batch size, L is the target sequence length, + S is the source sequence length. attn_mask ensures that position i is allowed to attend the unmasked + positions. If a ByteTensor is provided, the non-zero positions are not allowed to attend + while the zero positions will be unchanged. If a BoolTensor is provided, positions with ``True`` + are not allowed to attend while ``False`` values will be unchanged. If a FloatTensor + is provided, it will be added to the attention weight. + + Outputs: + - attn_output: :math:`(L, N, E)` where L is the target sequence length, N is the batch size, + E is the embedding dimension. + - attn_output_weights: :math:`(N, L, S)` where N is the batch size, + L is the target sequence length, S is the source sequence length. + """ + + tgt_len, bsz, embed_dim = query.size() + assert embed_dim == embed_dim_to_check + assert key.size(0) == value.size(0) and key.size(1) == value.size(1) + + head_dim = embed_dim // num_heads + assert ( + head_dim * num_heads == embed_dim + ), "embed_dim must be divisible by num_heads" + + scaling = float(head_dim) ** -0.5 + + if torch.equal(query, key) and torch.equal(key, value): + # self-attention + q, k, v = nn.functional.linear(query, in_proj_weight, in_proj_bias).chunk( + 3, dim=-1 + ) + + elif torch.equal(key, value): + # encoder-decoder attention + # This is inline in_proj function with in_proj_weight and in_proj_bias + _b = in_proj_bias + _start = 0 + _end = embed_dim + _w = in_proj_weight[_start:_end, :] + if _b is not None: + _b = _b[_start:_end] + q = nn.functional.linear(query, _w, _b) + + # This is inline in_proj function with in_proj_weight and in_proj_bias + _b = in_proj_bias + _start = embed_dim + _end = None + _w = in_proj_weight[_start:, :] + if _b is not None: + _b = _b[_start:] + k, v = nn.functional.linear(key, _w, _b).chunk(2, dim=-1) + + else: + # This is inline in_proj function with in_proj_weight and in_proj_bias + _b = in_proj_bias + _start = 0 + _end = embed_dim + _w = in_proj_weight[_start:_end, :] + if _b is not None: + _b = _b[_start:_end] + q = nn.functional.linear(query, _w, _b) + + # This is inline in_proj function with in_proj_weight and in_proj_bias + _b = in_proj_bias + _start = embed_dim + _end = embed_dim * 2 + _w = in_proj_weight[_start:_end, :] + if _b is not None: + _b = _b[_start:_end] + k = nn.functional.linear(key, _w, _b) + + # This is inline in_proj function with in_proj_weight and in_proj_bias + _b = in_proj_bias + _start = embed_dim * 2 + _end = None + _w = in_proj_weight[_start:, :] + if _b is not None: + _b = _b[_start:] + v = nn.functional.linear(value, _w, _b) + + if attn_mask is not None: + assert ( + attn_mask.dtype == torch.float32 + or attn_mask.dtype == torch.float64 + or attn_mask.dtype == torch.float16 + or attn_mask.dtype == torch.uint8 + or attn_mask.dtype == torch.bool + ), "Only float, byte, and bool types are supported for attn_mask, not {}".format( + attn_mask.dtype + ) + if attn_mask.dtype == torch.uint8: + warnings.warn( + "Byte tensor for attn_mask is deprecated. Use bool tensor instead." + ) + attn_mask = attn_mask.to(torch.bool) + + if attn_mask.dim() == 2: + attn_mask = attn_mask.unsqueeze(0) + if list(attn_mask.size()) != [1, query.size(0), key.size(0)]: + raise RuntimeError("The size of the 2D attn_mask is not correct.") + elif attn_mask.dim() == 3: + if list(attn_mask.size()) != [ + bsz * num_heads, + query.size(0), + key.size(0), + ]: + raise RuntimeError("The size of the 3D attn_mask is not correct.") + else: + raise RuntimeError( + "attn_mask's dimension {} is not supported".format(attn_mask.dim()) + ) + # attn_mask's dim is 3 now. + + # convert ByteTensor key_padding_mask to bool + if key_padding_mask is not None and key_padding_mask.dtype == torch.uint8: + warnings.warn( + "Byte tensor for key_padding_mask is deprecated. Use bool tensor instead." + ) + key_padding_mask = key_padding_mask.to(torch.bool) + + q = (q * scaling).contiguous().view(tgt_len, bsz, num_heads, head_dim) + k = k.contiguous().view(-1, bsz, num_heads, head_dim) + v = v.contiguous().view(-1, bsz * num_heads, head_dim).transpose(0, 1) + + src_len = k.size(0) + + if key_padding_mask is not None: + assert key_padding_mask.size(0) == bsz, "{} == {}".format( + key_padding_mask.size(0), bsz + ) + assert key_padding_mask.size(1) == src_len, "{} == {}".format( + key_padding_mask.size(1), src_len + ) + + q = q.transpose(0, 1) # (batch, time1, head, d_k) + + pos_emb_bsz = pos_emb.size(0) + assert pos_emb_bsz in (1, bsz) # actually it is 1 + p = self.linear_pos(pos_emb).view(pos_emb_bsz, -1, num_heads, head_dim) + # (batch, 2*time1, head, d_k) --> (batch, head, d_k, 2*time -1) + p = p.permute(0, 2, 3, 1) + + q_with_bias_u = (q + self._pos_bias_u()).transpose( + 1, 2 + ) # (batch, head, time1, d_k) + + q_with_bias_v = (q + self._pos_bias_v()).transpose( + 1, 2 + ) # (batch, head, time1, d_k) + + # compute attention score + # first compute matrix a and matrix c + # as described in "Transformer-XL: Attentive Language Models Beyond a Fixed-Length Context" Section 3.3 + k = k.permute(1, 2, 3, 0) # (batch, head, d_k, time2) + matrix_ac = torch.matmul(q_with_bias_u, k) # (batch, head, time1, time2) + + # compute matrix b and matrix d + matrix_bd = torch.matmul(q_with_bias_v, p) # (batch, head, time1, 2*time1-1) + matrix_bd = self.rel_shift(matrix_bd, left_context) + + attn_output_weights = matrix_ac + matrix_bd # (batch, head, time1, time2) + + attn_output_weights = attn_output_weights.view(bsz * num_heads, tgt_len, -1) + + assert list(attn_output_weights.size()) == [ + bsz * num_heads, + tgt_len, + src_len, + ] + + if attn_mask is not None: + if attn_mask.dtype == torch.bool: + attn_output_weights.masked_fill_(attn_mask, float("-inf")) + else: + attn_output_weights += attn_mask + + if key_padding_mask is not None: + attn_output_weights = attn_output_weights.view( + bsz, num_heads, tgt_len, src_len + ) + attn_output_weights = attn_output_weights.masked_fill( + key_padding_mask.unsqueeze(1).unsqueeze(2), + float("-inf"), + ) + attn_output_weights = attn_output_weights.view( + bsz * num_heads, tgt_len, src_len + ) + + attn_output_weights = nn.functional.softmax(attn_output_weights, dim=-1) + + # If we are using dynamic_chunk_training and setting a limited + # num_left_chunks, the attention may only see the padding values which + # will also be masked out by `key_padding_mask`, at this circumstances, + # the whole column of `attn_output_weights` will be `-inf` + # (i.e. be `nan` after softmax), so, we fill `0.0` at the masking + # positions to avoid invalid loss value below. + if ( + attn_mask is not None + and attn_mask.dtype == torch.bool + and key_padding_mask is not None + ): + if attn_mask.size(0) != 1: + attn_mask = attn_mask.view(bsz, num_heads, tgt_len, src_len) + combined_mask = attn_mask | key_padding_mask.unsqueeze(1).unsqueeze(2) + else: + # attn_mask.shape == (1, tgt_len, src_len) + combined_mask = attn_mask.unsqueeze(0) | key_padding_mask.unsqueeze( + 1 + ).unsqueeze(2) + + attn_output_weights = attn_output_weights.view( + bsz, num_heads, tgt_len, src_len + ) + attn_output_weights = attn_output_weights.masked_fill(combined_mask, 0.0) + attn_output_weights = attn_output_weights.view( + bsz * num_heads, tgt_len, src_len + ) + + attn_output_weights = nn.functional.dropout( + attn_output_weights, p=dropout_p, training=training + ) + + attn_output = torch.bmm(attn_output_weights, v) + assert list(attn_output.size()) == [bsz * num_heads, tgt_len, head_dim] + attn_output = ( + attn_output.transpose(0, 1).contiguous().view(tgt_len, bsz, embed_dim) + ) + attn_output = nn.functional.linear(attn_output, out_proj_weight, out_proj_bias) + + if need_weights: + # average attention weights over heads + attn_output_weights = attn_output_weights.view( + bsz, num_heads, tgt_len, src_len + ) + return attn_output, attn_output_weights.sum(dim=1) / num_heads + else: + return attn_output, None + + +class ConvolutionModule(nn.Module): + """ConvolutionModule in Conformer model. + Modified from https://github.com/espnet/espnet/blob/master/espnet/nets/pytorch_backend/conformer/convolution.py + + Args: + channels (int): The number of channels of conv layers. + kernel_size (int): Kernerl size of conv layers. + bias (bool): Whether to use bias in conv layers (default=True). + causal (bool): Whether to use causal convolution. + + """ + + def __init__( + self, + channels: int, + kernel_size: int, + bias: bool = True, + causal: bool = False, + ) -> None: + """Construct an ConvolutionModule object.""" + super(ConvolutionModule, self).__init__() + # kernerl_size should be a odd number for 'SAME' padding + assert (kernel_size - 1) % 2 == 0 + + self.causal = causal + + self.pointwise_conv1 = ScaledConv1d( + channels, + 2 * channels, + kernel_size=1, + stride=1, + padding=0, + bias=bias, + ) + + # after pointwise_conv1 we put x through a gated linear unit (nn.functional.glu). + # For most layers the normal rms value of channels of x seems to be in the range 1 to 4, + # but sometimes, for some reason, for layer 0 the rms ends up being very large, + # between 50 and 100 for different channels. This will cause very peaky and + # sparse derivatives for the sigmoid gating function, which will tend to make + # the loss function not learn effectively. (for most layers the average absolute values + # are in the range 0.5..9.0, and the average p(x>0), i.e. positive proportion, + # at the output of pointwise_conv1.output is around 0.35 to 0.45 for different + # layers, which likely breaks down as 0.5 for the "linear" half and + # 0.2 to 0.3 for the part that goes into the sigmoid. The idea is that if we + # constrain the rms values to a reasonable range via a constraint of max_abs=10.0, + # it will be in a better position to start learning something, i.e. to latch onto + # the correct range. + self.deriv_balancer1 = ActivationBalancer( + channel_dim=1, max_abs=10.0, min_positive=0.05, max_positive=1.0 + ) + + self.lorder = kernel_size - 1 + padding = (kernel_size - 1) // 2 + if self.causal: + padding = 0 + + self.depthwise_conv = ScaledConv1d( + channels, + channels, + kernel_size, + stride=1, + padding=padding, + groups=channels, + bias=bias, + ) + + self.deriv_balancer2 = ActivationBalancer( + channel_dim=1, min_positive=0.05, max_positive=1.0 + ) + + self.activation = DoubleSwish() + + self.pointwise_conv2 = ScaledConv1d( + channels, + channels, + kernel_size=1, + stride=1, + padding=0, + bias=bias, + initial_scale=0.25, + ) + + def forward( + self, + x: Tensor, + cache: Optional[Tensor] = None, + right_context: int = 0, + src_key_padding_mask: Optional[Tensor] = None, + ) -> Tuple[Tensor, Tensor]: + """Compute convolution module. + + Args: + x: Input tensor (#time, batch, channels). + cache: The cache of depthwise_conv, only used in real streaming + decoding. + right_context: + How many future frames the attention can see in current chunk. + Note: It's not that each individual frame has `right_context` frames + of right context, some have more. + src_key_padding_mask: the mask for the src keys per batch (optional). + + Returns: + Tensor: Output tensor (#time, batch, channels). + If cache is None return the output tensor (#time, batch, channels). + If cache is not None, return a tuple of Tensor, the first one is + the output tensor (#time, batch, channels), the second one is the + new cache for next chunk (#kernel_size - 1, batch, channels). + """ + # exchange the temporal dimension and the feature dimension + x = x.permute(1, 2, 0) # (#batch, channels, time). + + # GLU mechanism + x = self.pointwise_conv1(x) # (batch, 2*channels, time) + + x = self.deriv_balancer1(x) + x = nn.functional.glu(x, dim=1) # (batch, channels, time) + + # 1D Depthwise Conv + if src_key_padding_mask is not None: + x.masked_fill_(src_key_padding_mask.unsqueeze(1).expand_as(x), 0.0) + if self.causal and self.lorder > 0: + if cache is None: + # Make depthwise_conv causal by + # manualy padding self.lorder zeros to the left + x = nn.functional.pad(x, (self.lorder, 0), "constant", 0.0) + else: + assert not self.training, "Cache should be None in training time" + assert cache.size(0) == self.lorder + x = torch.cat([cache.permute(1, 2, 0), x], dim=2) + if right_context > 0: + cache = x.permute(2, 0, 1)[ + -(self.lorder + right_context) : (-right_context), # noqa + ..., + ] + else: + cache = x.permute(2, 0, 1)[-self.lorder :, ...] # noqa + + x = self.depthwise_conv(x) + + x = self.deriv_balancer2(x) + x = self.activation(x) + + x = self.pointwise_conv2(x) # (batch, channel, time) + + # torch.jit.script requires return types be the same as annotated above + if cache is None: + cache = torch.empty(0) + + return x.permute(2, 0, 1), cache + + +class Conv2dSubsampling(nn.Module): + """Convolutional 2D subsampling (to 1/4 length). + + Convert an input of shape (N, T, idim) to an output + with shape (N, T', odim), where + T' = ((T-1)//2 - 1)//2, which approximates T' == T//4 + + It is based on + https://github.com/espnet/espnet/blob/master/espnet/nets/pytorch_backend/transformer/subsampling.py # noqa + """ + + def __init__( + self, + in_channels: int, + out_channels: int, + layer1_channels: int = 8, + layer2_channels: int = 32, + layer3_channels: int = 128, + ) -> None: + """ + Args: + in_channels: + Number of channels in. The input shape is (N, T, in_channels). + Caution: It requires: T >=7, in_channels >=7 + out_channels + Output dim. The output shape is (N, ((T-1)//2 - 1)//2, out_channels) + layer1_channels: + Number of channels in layer1 + layer1_channels: + Number of channels in layer2 + """ + assert in_channels >= 7 + super().__init__() + + self.conv = nn.Sequential( + ScaledConv2d( + in_channels=1, + out_channels=layer1_channels, + kernel_size=3, + padding=1, + ), + ActivationBalancer(channel_dim=1), + DoubleSwish(), + ScaledConv2d( + in_channels=layer1_channels, + out_channels=layer2_channels, + kernel_size=3, + stride=2, + ), + ActivationBalancer(channel_dim=1), + DoubleSwish(), + ScaledConv2d( + in_channels=layer2_channels, + out_channels=layer3_channels, + kernel_size=3, + stride=2, + ), + ActivationBalancer(channel_dim=1), + DoubleSwish(), + ) + self.out = ScaledLinear( + layer3_channels * (((in_channels - 1) // 2 - 1) // 2), out_channels + ) + # set learn_eps=False because out_norm is preceded by `out`, and `out` + # itself has learned scale, so the extra degree of freedom is not + # needed. + self.out_norm = BasicNorm(out_channels, learn_eps=False) + # constrain median of output to be close to zero. + self.out_balancer = ActivationBalancer( + channel_dim=-1, min_positive=0.45, max_positive=0.55 + ) + + def forward(self, x: torch.Tensor) -> torch.Tensor: + """Subsample x. + + Args: + x: + Its shape is (N, T, idim). + + Returns: + Return a tensor of shape (N, ((T-1)//2 - 1)//2, odim) + """ + # On entry, x is (N, T, idim) + x = x.unsqueeze(1) # (N, T, idim) -> (N, 1, T, idim) i.e., (N, C, H, W) + x = self.conv(x) + # Now x is of shape (N, odim, ((T-1)//2 - 1)//2, ((idim-1)//2 - 1)//2) + b, c, t, f = x.size() + x = self.out(x.transpose(1, 2).contiguous().view(b, t, c * f)) + # Now x is of shape (N, ((T-1)//2 - 1))//2, odim) + x = self.out_norm(x) + x = self.out_balancer(x) + return x + + +class RandomCombine(nn.Module): + """ + This module combines a list of Tensors, all with the same shape, to + produce a single output of that same shape which, in training time, + is a random combination of all the inputs; but which in test time + will be just the last input. + + The idea is that the list of Tensors will be a list of outputs of multiple + conformer layers. This has a similar effect as iterated loss. (See: + DEJA-VU: DOUBLE FEATURE PRESENTATION AND ITERATED LOSS IN DEEP TRANSFORMER + NETWORKS). + """ + + def __init__( + self, + num_inputs: int, + final_weight: float = 0.5, + pure_prob: float = 0.5, + stddev: float = 2.0, + ) -> None: + """ + Args: + num_inputs: + The number of tensor inputs, which equals the number of layers' + outputs that are fed into this module. E.g. in an 18-layer neural + net if we output layers 16, 12, 18, num_inputs would be 3. + final_weight: + The amount of weight or probability we assign to the + final layer when randomly choosing layers or when choosing + continuous layer weights. + pure_prob: + The probability, on each frame, with which we choose + only a single layer to output (rather than an interpolation) + stddev: + A standard deviation that we add to log-probs for computing + randomized weights. + + The method of choosing which layers, or combinations of layers, to use, + is conceptually as follows:: + + With probability `pure_prob`:: + With probability `final_weight`: choose final layer, + Else: choose random non-final layer. + Else:: + Choose initial log-weights that correspond to assigning + weight `final_weight` to the final layer and equal + weights to other layers; then add Gaussian noise + with variance `stddev` to these log-weights, and normalize + to weights (note: the average weight assigned to the + final layer here will not be `final_weight` if stddev>0). + """ + super().__init__() + assert 0 <= pure_prob <= 1, pure_prob + assert 0 < final_weight < 1, final_weight + assert num_inputs >= 1 + + self.num_inputs = num_inputs + self.final_weight = final_weight + self.pure_prob = pure_prob + self.stddev = stddev + + self.final_log_weight = ( + torch.tensor((final_weight / (1 - final_weight)) * (self.num_inputs - 1)) + .log() + .item() + ) + + def forward(self, inputs: List[Tensor]) -> Tensor: + """Forward function. + Args: + inputs: + A list of Tensor, e.g. from various layers of a transformer. + All must be the same shape, of (*, num_channels) + Returns: + A Tensor of shape (*, num_channels). In test mode + this is just the final input. + """ + num_inputs = self.num_inputs + assert len(inputs) == num_inputs + if not self.training or torch.jit.is_scripting(): + return inputs[-1] + + # Shape of weights: (*, num_inputs) + num_channels = inputs[0].shape[-1] + num_frames = inputs[0].numel() // num_channels + + ndim = inputs[0].ndim + # stacked_inputs: (num_frames, num_channels, num_inputs) + stacked_inputs = torch.stack(inputs, dim=ndim).reshape( + (num_frames, num_channels, num_inputs) + ) + + # weights: (num_frames, num_inputs) + weights = self._get_random_weights( + inputs[0].dtype, inputs[0].device, num_frames + ) + + weights = weights.reshape(num_frames, num_inputs, 1) + # ans: (num_frames, num_channels, 1) + ans = torch.matmul(stacked_inputs, weights) + # ans: (*, num_channels) + + ans = ans.reshape(inputs[0].shape[:-1] + (num_channels,)) + + # The following if causes errors for torch script in torch 1.6.0 + # if __name__ == "__main__": + # # for testing only... + # print("Weights = ", weights.reshape(num_frames, num_inputs)) + return ans + + def _get_random_weights( + self, dtype: torch.dtype, device: torch.device, num_frames: int + ) -> Tensor: + """Return a tensor of random weights, of shape + `(num_frames, self.num_inputs)`, + Args: + dtype: + The data-type desired for the answer, e.g. float, double. + device: + The device needed for the answer. + num_frames: + The number of sets of weights desired + Returns: + A tensor of shape (num_frames, self.num_inputs), such that + `ans.sum(dim=1)` is all ones. + """ + pure_prob = self.pure_prob + if pure_prob == 0.0: + return self._get_random_mixed_weights(dtype, device, num_frames) + elif pure_prob == 1.0: + return self._get_random_pure_weights(dtype, device, num_frames) + else: + p = self._get_random_pure_weights(dtype, device, num_frames) + m = self._get_random_mixed_weights(dtype, device, num_frames) + return torch.where( + torch.rand(num_frames, 1, device=device) < self.pure_prob, p, m + ) + + def _get_random_pure_weights( + self, dtype: torch.dtype, device: torch.device, num_frames: int + ): + """Return a tensor of random one-hot weights, of shape + `(num_frames, self.num_inputs)`, + Args: + dtype: + The data-type desired for the answer, e.g. float, double. + device: + The device needed for the answer. + num_frames: + The number of sets of weights desired. + Returns: + A one-hot tensor of shape `(num_frames, self.num_inputs)`, with + exactly one weight equal to 1.0 on each frame. + """ + final_prob = self.final_weight + + # final contains self.num_inputs - 1 in all elements + final = torch.full((num_frames,), self.num_inputs - 1, device=device) + # nonfinal contains random integers in [0..num_inputs - 2], these are for non-final weights. + nonfinal = torch.randint(self.num_inputs - 1, (num_frames,), device=device) + + indexes = torch.where( + torch.rand(num_frames, device=device) < final_prob, final, nonfinal + ) + ans = torch.nn.functional.one_hot(indexes, num_classes=self.num_inputs).to( + dtype=dtype + ) + return ans + + def _get_random_mixed_weights( + self, dtype: torch.dtype, device: torch.device, num_frames: int + ): + """Return a tensor of random one-hot weights, of shape + `(num_frames, self.num_inputs)`, + Args: + dtype: + The data-type desired for the answer, e.g. float, double. + device: + The device needed for the answer. + num_frames: + The number of sets of weights desired. + Returns: + A tensor of shape (num_frames, self.num_inputs), which elements + in [0..1] that sum to one over the second axis, i.e. + `ans.sum(dim=1)` is all ones. + """ + logprobs = ( + torch.randn(num_frames, self.num_inputs, dtype=dtype, device=device) + * self.stddev + ) + logprobs[:, -1] += self.final_log_weight + return logprobs.softmax(dim=1) + + +def _test_random_combine(final_weight: float, pure_prob: float, stddev: float): + print( + f"_test_random_combine: final_weight={final_weight}, pure_prob={pure_prob}, stddev={stddev}" + ) + num_inputs = 3 + num_channels = 50 + m = RandomCombine( + num_inputs=num_inputs, + final_weight=final_weight, + pure_prob=pure_prob, + stddev=stddev, + ) + + x = [torch.ones(3, 4, num_channels) for _ in range(num_inputs)] + + y = m(x) + assert y.shape == x[0].shape + assert torch.allclose(y, x[0]) # .. since actually all ones. + + +def _test_random_combine_main(): + _test_random_combine(0.999, 0, 0.0) + _test_random_combine(0.5, 0, 0.0) + _test_random_combine(0.999, 0, 0.0) + _test_random_combine(0.5, 0, 0.3) + _test_random_combine(0.5, 1, 0.3) + _test_random_combine(0.5, 0.5, 0.3) + + feature_dim = 50 + c = Conformer(num_features=feature_dim, d_model=128, nhead=4) + batch_size = 5 + seq_len = 20 + # Just make sure the forward pass runs. + f = c( + torch.randn(batch_size, seq_len, feature_dim), + torch.full((batch_size,), seq_len, dtype=torch.int64), + ) + f # to remove flake8 warnings + + +if __name__ == "__main__": + feature_dim = 50 + c = Conformer(num_features=feature_dim, d_model=128, nhead=4) + batch_size = 5 + seq_len = 20 + # Just make sure the forward pass runs. + f = c( + torch.randn(batch_size, seq_len, feature_dim), + torch.full((batch_size,), seq_len, dtype=torch.int64), + warmup=0.5, + ) + + _test_random_combine_main() diff --git a/egs/librispeech/ASR/incremental_transf/decode.py b/egs/librispeech/ASR/incremental_transf/decode.py new file mode 100755 index 000000000..8b993f638 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/decode.py @@ -0,0 +1,972 @@ +#!/usr/bin/env python3 +# +# Copyright 2021-2022 Xiaomi Corporation (Author: Fangjun Kuang, +# Zengwei Yao, +# Xiaoyu Yang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +""" +Usage: +(1) greedy search +./pruned_transducer_stateless5/decode.py \ + --epoch 28 \ + --avg 15 \ + --exp-dir ./pruned_transducer_stateless5/exp \ + --max-duration 600 \ + --decoding-method greedy_search +(2) beam search (not recommended) +./pruned_transducer_stateless5/decode.py \ + --epoch 28 \ + --avg 15 \ + --exp-dir ./pruned_transducer_stateless5/exp \ + --max-duration 600 \ + --decoding-method beam_search \ + --beam-size 4 +(3) modified beam search +./pruned_transducer_stateless5/decode.py \ + --epoch 28 \ + --avg 15 \ + --exp-dir ./pruned_transducer_stateless5/exp \ + --max-duration 600 \ + --decoding-method modified_beam_search \ + --beam-size 4 +(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 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 + +(8) modified beam search with RNNLM shallow fusion (with LG) +./pruned_transducer_stateless5/decode.py \ + --epoch 35 \ + --avg 15 \ + --exp-dir ./pruned_transducer_stateless5/exp \ + --max-duration 600 \ + --decoding-method fast_beam_search_nbest_LG \ + --beam 4 \ + --max-contexts 4 \ + --rnn-lm-scale 0.4 \ + --rnn-lm-exp-dir /path/to/RNNLM/exp \ + --rnn-lm-epoch 99 \ + --rnn-lm-avg 1 \ + --rnn-lm-num-layers 3 \ + --rnn-lm-tie-weights 1 + + +""" + + +import argparse +import logging +import math +from collections import defaultdict +from pathlib import Path +from typing import Dict, List, Optional, Tuple + +import k2 +import sentencepiece as spm +import torch +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, + modified_beam_search, + modified_beam_search_rnnlm_shallow_fusion, +) +from train import add_model_arguments, get_params, get_transducer_model + +from icefall.checkpoint import ( + average_checkpoints, + average_checkpoints_with_averaged_model, + find_checkpoints, + load_checkpoint, +) +from icefall.lexicon import Lexicon +from icefall.rnn_lm.model import RnnLmModel +from icefall.utils import ( + AttributeDict, + setup_logger, + store_transcripts, + str2bool, + write_error_stats, +) + +LOG_EPS = math.log(1e-10) + + +def get_parser(): + parser = argparse.ArgumentParser( + formatter_class=argparse.ArgumentDefaultsHelpFormatter + ) + + parser.add_argument( + "--epoch", + type=int, + default=30, + help="""It specifies the checkpoint to use for decoding. + Note: Epoch counts from 1. + You can specify --avg to use more checkpoints for model averaging.""", + ) + + parser.add_argument( + "--iter", + type=int, + default=0, + help="""If positive, --epoch is ignored and it + will use the checkpoint exp_dir/checkpoint-iter.pt. + You can specify --avg to use more checkpoints for model averaging. + """, + ) + + parser.add_argument( + "--avg", + type=int, + default=15, + help="Number of checkpoints to average. Automatically select " + "consecutive checkpoints before the checkpoint specified by " + "'--epoch' and '--iter'", + ) + + parser.add_argument( + "--use-averaged-model", + type=str2bool, + 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`." + "Actually only the models with epoch number of `epoch-avg` and " + "`epoch` are loaded for averaging. ", + ) + + parser.add_argument( + "--exp-dir", + type=str, + default="pruned_transducer_stateless5/exp", + help="The experiment dir", + ) + + parser.add_argument( + "--bpe-model", + type=str, + default="data/lang_bpe_500/bpe.model", + 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, + default="greedy_search", + help="""Possible values are: + - greedy_search + - beam_search + - modified_beam_search + - fast_beam_search + - fast_beam_search_LG + - fast_beam_search_nbest + - fast_beam_search_nbest_oracle + - fast_beam_search_nbest_LG + - modified_beam_search_rnnlm_shallow_fusion # for rnn lm shallow fusion + If you use fast_beam_search_nbest_LG, you have to specify + `--lang-dir`, which should contain `LG.pt`. + """, + ) + + parser.add_argument( + "--beam-size", + type=int, + default=4, + help="""An integer indicating how many candidates we will keep for each + frame. Used only when --decoding-method is beam_search or + modified_beam_search.""", + ) + + parser.add_argument( + "--beam", + type=float, + 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, fast_beam_search_LG, + 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 and fast_beam_search_LG. + It specifies the scale for n-gram LM scores. + """, + ) + + parser.add_argument( + "--decode-chunk-size", + type=int, + default=16, + help="The chunk size for decoding (in frames after subsampling)", + ) + + parser.add_argument( + "--left-context", + type=int, + default=64, + help="left context can be seen during decoding (in frames after subsampling)", + ) + + parser.add_argument( + "--max-contexts", + type=int, + default=8, + help="""Used only when --decoding-method is fast_beam_search_LG, + 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=64, + help="""Used only when --decoding-method is fast_beam_search_LG, + fast_beam_search, fast_beam_search_nbest, fast_beam_search_nbest_LG, + and fast_beam_search_nbest_oracle""", + ) + + parser.add_argument( + "--context-size", + type=int, + default=2, + help="The context size in the decoder. 1 means bigram; 2 means tri-gram", + ) + + parser.add_argument( + "--max-sym-per-frame", + type=int, + default=1, + help="""Maximum number of symbols per frame. + 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""", + ) + + parser.add_argument( + "--simulate-streaming", + type=str2bool, + default=False, + help="""Whether to simulate streaming in decoding, this is a good way to + test a streaming model. + """, + ) + + parser.add_argument( + "--rnn-lm-scale", + type=float, + default=0.0, + help="""Used only when --method is modified_beam_search_rnnlm_shallow_fusion. + It specifies the path to RNN LM exp dir. + """, + ) + + parser.add_argument( + "--rnn-lm-exp-dir", + type=str, + default="rnn_lm/exp", + help="""Used only when --method is modified_beam_search_rnnlm_shallow_fusion. + It specifies the path to RNN LM exp dir. + """, + ) + + parser.add_argument( + "--rnn-lm-epoch", + type=int, + default=7, + help="""Used only when --method is modified_beam_search_rnnlm_shallow_fusion. + It specifies the checkpoint to use. + """, + ) + + parser.add_argument( + "--rnn-lm-avg", + type=int, + default=2, + help="""Used only when --method is modified_beam_search_rnnlm_shallow_fusion. + It specifies the number of checkpoints to average. + """, + ) + + parser.add_argument( + "--rnn-lm-embedding-dim", + type=int, + default=2048, + help="Embedding dim of the model", + ) + + parser.add_argument( + "--rnn-lm-hidden-dim", + type=int, + default=2048, + help="Hidden dim of the model", + ) + + parser.add_argument( + "--rnn-lm-num-layers", + type=int, + default=4, + help="Number of RNN layers the model", + ) + parser.add_argument( + "--rnn-lm-tie-weights", + type=str2bool, + default=False, + help="""True to share the weights between the input embedding layer and the + last output linear layer + """, + ) + add_model_arguments(parser) + + return parser + + +def decode_one_batch( + params: AttributeDict, + model: nn.Module, + sp: spm.SentencePieceProcessor, + batch: dict, + word_table: Optional[k2.SymbolTable] = None, + decoding_graph: Optional[k2.Fsa] = None, + rnnlm: Optional[RnnLmModel] = None, + rnnlm_scale: float = 1.0, +) -> Dict[str, List[List[str]]]: + """Decode one batch and return the result in a dict. The dict has the + following format: + + - key: It indicates the setting used for decoding. For example, + if greedy_search is used, it would be "greedy_search" + If beam search with a beam size of 7 is used, it would be + "beam_7" + - value: It contains the decoding result. `len(value)` equals to + batch size. `value[i]` is the decoding result for the i-th + utterance in the given batch. + Args: + params: + It's the return value of :func:`get_params`. + model: + The neural model. + sp: + The BPE model. + 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 LG, Used + only when --decoding_method is fast_beam_search, fast_beam_search_LG, 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. + """ + device = next(model.parameters()).device + feature = batch["inputs"] + assert feature.ndim == 3 + + feature = feature.to(device) + # at entry, feature is (N, T, C) + + supervisions = batch["supervisions"] + feature_lens = supervisions["num_frames"].to(device) + + if params.simulate_streaming: + feature_lens += params.left_context + feature = torch.nn.functional.pad( + feature, + pad=(0, 0, 0, params.left_context), + value=LOG_EPS, + ) + encoder_out, encoder_out_lens, _ = model.encoder.streaming_forward( + x=feature, + x_lens=feature_lens, + chunk_size=params.decode_chunk_size, + left_context=params.left_context, + simulate_streaming=True, + ) + else: + encoder_out, encoder_out_lens = model.encoder(x=feature, x_lens=feature_lens) + + hyps = [] + + if ( + params.decoding_method == "fast_beam_search" + or params.decoding_method == "fast_beam_search_LG" + ): + hyp_tokens = fast_beam_search_one_best( + 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, + ) + if params.decoding_method == "fast_beam_search": + for hyp in sp.decode(hyp_tokens): + hyps.append(hyp.split()) + else: + for hyp in hyp_tokens: + hyps.append([word_table[i] for i in hyp]) + 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: + hyp_tokens = greedy_search_batch( + model=model, + encoder_out=encoder_out, + encoder_out_lens=encoder_out_lens, + ) + for hyp in sp.decode(hyp_tokens): + hyps.append(hyp.split()) + elif params.decoding_method == "modified_beam_search": + hyp_tokens = modified_beam_search( + model=model, + encoder_out=encoder_out, + encoder_out_lens=encoder_out_lens, + beam=params.beam_size, + ) + for hyp in sp.decode(hyp_tokens): + hyps.append(hyp.split()) + elif params.decoding_method == "modified_beam_search_rnnlm_shallow_fusion": + hyp_tokens = modified_beam_search_rnnlm_shallow_fusion( + model=model, + encoder_out=encoder_out, + encoder_out_lens=encoder_out_lens, + beam=params.beam_size, + sp=sp, + rnnlm=rnnlm, + rnnlm_scale=rnnlm_scale, + ) + for hyp in sp.decode(hyp_tokens): + hyps.append(hyp.split()) + else: + batch_size = encoder_out.size(0) + + for i in range(batch_size): + # fmt: off + encoder_out_i = encoder_out[i:i+1, :encoder_out_lens[i]] + # fmt: on + if params.decoding_method == "greedy_search": + hyp = greedy_search( + model=model, + encoder_out=encoder_out_i, + max_sym_per_frame=params.max_sym_per_frame, + ) + elif params.decoding_method == "beam_search": + hyp = beam_search( + model=model, + encoder_out=encoder_out_i, + beam=params.beam_size, + ) + else: + raise ValueError( + f"Unsupported decoding method: {params.decoding_method}" + ) + hyps.append(sp.decode(hyp).split()) + + if params.decoding_method == "greedy_search": + return {"greedy_search": 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} + + +def decode_dataset( + dl: torch.utils.data.DataLoader, + params: AttributeDict, + model: nn.Module, + sp: spm.SentencePieceProcessor, + word_table: Optional[k2.SymbolTable] = None, + decoding_graph: Optional[k2.Fsa] = None, + rnnlm: Optional[RnnLmModel] = None, + rnnlm_scale: float = 1.0, +) -> Dict[str, List[Tuple[str, List[str], List[str]]]]: + """Decode dataset. + + Args: + dl: + PyTorch's dataloader containing the dataset to decode. + params: + It is returned by :func:`get_params`. + model: + 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 LG, Used + only when --decoding_method is fast_beam_search, fast_beam_search_LG, 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. + Its value is a list of tuples. Each tuple contains two elements: + The first is the reference transcript, and the second is the + predicted result. + """ + num_cuts = 0 + + try: + num_batches = len(dl) + except TypeError: + num_batches = "?" + + if params.decoding_method == "greedy_search": + log_interval = 50 + else: + log_interval = 20 + + results = defaultdict(list) + for batch_idx, batch in enumerate(dl): + texts = batch["supervisions"]["text"] + cut_ids = [cut.id for cut in batch["supervisions"]["cut"]] + logging.info(f"Decoding {batch_idx}-th batch") + + hyps_dict = decode_one_batch( + params=params, + model=model, + sp=sp, + decoding_graph=decoding_graph, + word_table=word_table, + batch=batch, + rnnlm=rnnlm, + rnnlm_scale=rnnlm_scale, + ) + + for name, hyps in hyps_dict.items(): + this_batch = [] + assert len(hyps) == len(texts) + for cut_id, hyp_words, ref_text in zip(cut_ids, hyps, texts): + ref_words = ref_text.split() + this_batch.append((cut_id, ref_words, hyp_words)) + + results[name].extend(this_batch) + + num_cuts += len(texts) + + if batch_idx % log_interval == 0: + batch_str = f"{batch_idx}/{num_batches}" + + logging.info(f"batch {batch_str}, cuts processed until now is {num_cuts}") + return results + + +def save_results( + params: AttributeDict, + test_set_name: str, + results_dict: Dict[str, List[Tuple[str, List[str], List[str]]]], +): + test_set_wers = dict() + for key, results in results_dict.items(): + recog_path = ( + params.res_dir / f"recogs-{test_set_name}-{key}-{params.suffix}.txt" + ) + results = sorted(results) + store_transcripts(filename=recog_path, texts=results) + logging.info(f"The transcripts are stored in {recog_path}") + + # The following prints out WERs, per-word error statistics and aligned + # ref/hyp pairs. + errs_filename = ( + params.res_dir / f"errs-{test_set_name}-{key}-{params.suffix}.txt" + ) + with open(errs_filename, "w") as f: + wer = write_error_stats( + f, f"{test_set_name}-{key}", results, enable_log=True + ) + test_set_wers[key] = wer + + logging.info("Wrote detailed error stats to {}".format(errs_filename)) + + test_set_wers = sorted(test_set_wers.items(), key=lambda x: x[1]) + errs_info = ( + params.res_dir / f"wer-summary-{test_set_name}-{key}-{params.suffix}.txt" + ) + with open(errs_info, "w") as f: + print("settings\tWER", file=f) + for key, val in test_set_wers: + print("{}\t{}".format(key, val), file=f) + + s = "\nFor {}, WER of different settings are:\n".format(test_set_name) + note = "\tbest for {}".format(test_set_name) + for key, val in test_set_wers: + s += "{}\t{}{}\n".format(key, val, note) + note = "" + logging.info(s) + + +@torch.no_grad() +def main(): + parser = get_parser() + LibriSpeechAsrDataModule.add_arguments(parser) + args = parser.parse_args() + args.exp_dir = Path(args.exp_dir) + + params = get_params() + params.update(vars(args)) + + assert params.decoding_method in ( + "greedy_search", + "beam_search", + "fast_beam_search", + "fast_beam_search_LG", + "fast_beam_search_nbest", + "fast_beam_search_nbest_LG", + "fast_beam_search_nbest_oracle", + "modified_beam_search", + "modified_beam_search_rnnlm_shallow_fusion", + ) + params.res_dir = params.exp_dir / params.decoding_method + + if params.iter > 0: + params.suffix = f"iter-{params.iter}-avg-{params.avg}" + else: + params.suffix = f"epoch-{params.epoch}-avg-{params.avg}" + if params.simulate_streaming: + params.suffix += f"-streaming-chunk-size-{params.decode_chunk_size}" + params.suffix += f"-left-context-{params.left_context}" + 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}" + 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}" + else: + params.suffix += f"-context-{params.context_size}" + params.suffix += f"-max-sym-per-frame-{params.max_sym_per_frame}" + + params.suffix += f"-rnnlm-lm-scale-{params.rnn_lm_scale}" + + if params.use_averaged_model: + params.suffix += "-use-averaged-model" + + setup_logger(f"{params.res_dir}/log-decode-{params.suffix}") + logging.info("Decoding started") + + device = torch.device("cpu") + if torch.cuda.is_available(): + device = torch.device("cuda", 0) + + logging.info(f"Device: {device}") + + sp = spm.SentencePieceProcessor() + sp.load(params.bpe_model) + + # and are defined in local/train_bpe_model.py + params.blank_id = sp.piece_to_id("") + params.unk_id = sp.piece_to_id("") + params.vocab_size = sp.get_piece_size() + + if params.simulate_streaming: + assert ( + params.causal_convolution + ), "Decoding in streaming requires causal convolution" + + logging.info(params) + + logging.info("About to create model") + model = get_transducer_model(params) + + if not params.use_averaged_model: + if params.iter > 0: + filenames = find_checkpoints(params.exp_dir, iteration=-params.iter)[ + : params.avg + ] + if len(filenames) == 0: + raise ValueError( + f"No checkpoints found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + elif len(filenames) < params.avg: + raise ValueError( + f"Not enough checkpoints ({len(filenames)}) found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + logging.info(f"averaging {filenames}") + model.to(device) + model.load_state_dict(average_checkpoints(filenames, device=device)) + elif params.avg == 1: + load_checkpoint(f"{params.exp_dir}/epoch-{params.epoch}.pt", model) + else: + start = params.epoch - params.avg + 1 + filenames = [] + for i in range(start, params.epoch + 1): + if i >= 1: + filenames.append(f"{params.exp_dir}/epoch-{i}.pt") + logging.info(f"averaging {filenames}") + model.to(device) + model.load_state_dict(average_checkpoints(filenames, device=device)) + else: + if params.iter > 0: + filenames = find_checkpoints(params.exp_dir, iteration=-params.iter)[ + : params.avg + 1 + ] + if len(filenames) == 0: + raise ValueError( + f"No checkpoints found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + elif len(filenames) < params.avg + 1: + raise ValueError( + f"Not enough checkpoints ({len(filenames)}) found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + filename_start = filenames[-1] + filename_end = filenames[0] + logging.info( + "Calculating the averaged model over iteration checkpoints" + f" from {filename_start} (excluded) to {filename_end}" + ) + model.to(device) + model.load_state_dict( + average_checkpoints_with_averaged_model( + filename_start=filename_start, + filename_end=filename_end, + device=device, + ) + ) + else: + assert params.avg > 0, params.avg + start = params.epoch - params.avg + assert start >= 1, start + filename_start = f"{params.exp_dir}/epoch-{start}.pt" + filename_end = f"{params.exp_dir}/epoch-{params.epoch}.pt" + logging.info( + f"Calculating the averaged model over epoch range from " + f"{start} (excluded) to {params.epoch}" + ) + model.to(device) + model.load_state_dict( + average_checkpoints_with_averaged_model( + filename_start=filename_start, + filename_end=filename_end, + device=device, + ) + ) + + model.to(device) + model.eval() + + rnn_lm_model = None + rnn_lm_scale = params.rnn_lm_scale + if params.decoding_method == "modified_beam_search_rnnlm_shallow_fusion": + rnn_lm_model = RnnLmModel( + vocab_size=params.vocab_size, + embedding_dim=params.rnn_lm_embedding_dim, + hidden_dim=params.rnn_lm_hidden_dim, + num_layers=params.rnn_lm_num_layers, + tie_weights=params.rnn_lm_tie_weights, + ) + assert params.rnn_lm_avg == 1 + + load_checkpoint( + f"{params.rnn_lm_exp_dir}/epoch-{params.rnn_lm_epoch}.pt", + rnn_lm_model, + ) + rnn_lm_model.to(device) + rnn_lm_model.eval() + + if "fast_beam_search" in params.decoding_method: + if "LG" in params.decoding_method: + 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}") + + # we need cut ids to display recognition results. + args.return_cuts = True + librispeech = LibriSpeechAsrDataModule(args) + + test_clean_cuts = librispeech.test_clean_cuts() + test_other_cuts = librispeech.test_other_cuts() + + test_clean_dl = librispeech.test_dataloaders(test_clean_cuts) + test_other_dl = librispeech.test_dataloaders(test_other_cuts) + + test_sets = ["test-clean", "test-other"] + test_dl = [test_clean_dl, test_other_dl] + + for test_set, test_dl in zip(test_sets, test_dl): + results_dict = decode_dataset( + dl=test_dl, + params=params, + model=model, + sp=sp, + word_table=word_table, + decoding_graph=decoding_graph, + rnnlm=rnn_lm_model, + rnnlm_scale=rnn_lm_scale, + ) + + save_results( + params=params, + test_set_name=test_set, + results_dict=results_dict, + ) + + logging.info("Done!") + + +if __name__ == "__main__": + main() diff --git a/egs/librispeech/ASR/incremental_transf/decode_stream.py b/egs/librispeech/ASR/incremental_transf/decode_stream.py new file mode 100644 index 000000000..e522943c0 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/decode_stream.py @@ -0,0 +1,146 @@ +# Copyright 2022 Xiaomi Corp. (authors: Wei Kang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import math +from typing import List, Optional, Tuple + +import k2 +import torch +from beam_search import Hypothesis, HypothesisList + +from icefall.utils import AttributeDict + + +class DecodeStream(object): + def __init__( + self, + params: AttributeDict, + cut_id: str, + initial_states: List[torch.Tensor], + decoding_graph: Optional[k2.Fsa] = None, + device: torch.device = torch.device("cpu"), + ) -> None: + """ + Args: + initial_states: + Initial decode states of the model, e.g. the return value of + `get_init_state` in conformer.py + decoding_graph: + Decoding graph used for decoding, may be a TrivialGraph or a HLG. + Used only when decoding_method is fast_beam_search. + device: + The device to run this stream. + """ + if params.decoding_method == "fast_beam_search": + assert decoding_graph is not None + assert device == decoding_graph.device + + self.params = params + self.cut_id = cut_id + self.LOG_EPS = math.log(1e-10) + + self.states = initial_states + + # It contains a 2-D tensors representing the feature frames. + self.features: torch.Tensor = None + + self.num_frames: int = 0 + # how many frames have been processed. (before subsampling). + # we only modify this value in `func:get_feature_frames`. + self.num_processed_frames: int = 0 + + self._done: bool = False + + # The transcript of current utterance. + self.ground_truth: str = "" + + # The decoding result (partial or final) of current utterance. + self.hyp: List = [] + + # how many frames have been processed, after subsampling (i.e. a + # cumulative sum of the second return value of + # encoder.streaming_forward + self.done_frames: int = 0 + + self.pad_length = (params.right_context + 2) * params.subsampling_factor + 3 + + if params.decoding_method == "greedy_search": + self.hyp = [params.blank_id] * params.context_size + elif params.decoding_method == "modified_beam_search": + self.hyps = HypothesisList() + self.hyps.add( + Hypothesis( + ys=[params.blank_id] * params.context_size, + log_prob=torch.zeros(1, dtype=torch.float32, device=device), + ) + ) + elif params.decoding_method == "fast_beam_search": + # The rnnt_decoding_stream for fast_beam_search. + self.rnnt_decoding_stream: k2.RnntDecodingStream = k2.RnntDecodingStream( + decoding_graph + ) + else: + raise ValueError(f"Unsupported decoding method: {params.decoding_method}") + + @property + def done(self) -> bool: + """Return True if all the features are processed.""" + return self._done + + @property + def id(self) -> str: + return self.cut_id + + def set_features( + self, + features: torch.Tensor, + ) -> None: + """Set features tensor of current utterance.""" + assert features.dim() == 2, features.dim() + self.features = torch.nn.functional.pad( + features, + (0, 0, 0, self.pad_length), + mode="constant", + value=self.LOG_EPS, + ) + self.num_frames = self.features.size(0) + + def get_feature_frames(self, chunk_size: int) -> Tuple[torch.Tensor, int]: + """Consume chunk_size frames of features""" + chunk_length = chunk_size + self.pad_length + + ret_length = min(self.num_frames - self.num_processed_frames, chunk_length) + + ret_features = self.features[ + self.num_processed_frames : self.num_processed_frames + ret_length # noqa + ] + + self.num_processed_frames += chunk_size + if self.num_processed_frames >= self.num_frames: + self._done = True + + return ret_features, ret_length + + def decoding_result(self) -> List[int]: + """Obtain current decoding result.""" + if self.params.decoding_method == "greedy_search": + return self.hyp[self.params.context_size :] # noqa + elif self.params.decoding_method == "modified_beam_search": + best_hyp = self.hyps.get_most_probable(length_norm=True) + return best_hyp.ys[self.params.context_size :] # noqa + else: + assert self.params.decoding_method == "fast_beam_search" + return self.hyp diff --git a/egs/librispeech/ASR/incremental_transf/decoder.py b/egs/librispeech/ASR/incremental_transf/decoder.py new file mode 100644 index 000000000..b59928103 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/decoder.py @@ -0,0 +1,123 @@ +# Copyright 2021 Xiaomi Corp. (authors: Fangjun Kuang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import torch +import torch.nn as nn +import torch.nn.functional as F +from scaling import ScaledConv1d, ScaledEmbedding + +from icefall.utils import is_jit_tracing + + +class Decoder(nn.Module): + """This class modifies the stateless decoder from the following paper: + + RNN-transducer with stateless prediction network + https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=9054419 + + It removes the recurrent connection from the decoder, i.e., the prediction + network. Different from the above paper, it adds an extra Conv1d + right after the embedding layer. + + TODO: Implement https://arxiv.org/pdf/2109.07513.pdf + """ + + def __init__( + self, + vocab_size: int, + decoder_dim: int, + blank_id: int, + context_size: int, + ): + """ + Args: + vocab_size: + Number of tokens of the modeling unit including blank. + decoder_dim: + Dimension of the input embedding, and of the decoder output. + blank_id: + The ID of the blank symbol. + context_size: + Number of previous words to use to predict the next word. + 1 means bigram; 2 means trigram. n means (n+1)-gram. + """ + super().__init__() + + self.embedding = ScaledEmbedding( + num_embeddings=vocab_size, + embedding_dim=decoder_dim, + padding_idx=blank_id, + ) + self.blank_id = blank_id + + assert context_size >= 1, context_size + self.context_size = context_size + self.vocab_size = vocab_size + if context_size > 1: + self.conv = ScaledConv1d( + in_channels=decoder_dim, + out_channels=decoder_dim, + kernel_size=context_size, + padding=0, + groups=decoder_dim, + bias=False, + ) + else: + # It is to support torch script + self.conv = nn.Identity() + + def forward( + self, + y: torch.Tensor, + need_pad: bool = True # Annotation should be Union[bool, torch.Tensor] + # but, torch.jit.script does not support Union. + ) -> torch.Tensor: + """ + Args: + y: + A 2-D tensor of shape (N, U). + need_pad: + True to left pad the input. Should be True during training. + False to not pad the input. Should be False during inference. + Returns: + Return a tensor of shape (N, U, decoder_dim). + """ + if isinstance(need_pad, torch.Tensor): + # This is for torch.jit.trace(), which cannot handle the case + # when the input argument is not a tensor. + need_pad = bool(need_pad) + + y = y.to(torch.int64) + # this stuff about clamp() is a temporary fix for a mismatch + # at utterance start, we use negative ids in beam_search.py + if torch.jit.is_tracing(): + # This is for exporting to PNNX via ONNX + embedding_out = self.embedding(y) + else: + embedding_out = self.embedding(y.clamp(min=0)) * (y >= 0).unsqueeze(-1) + if self.context_size > 1: + embedding_out = embedding_out.permute(0, 2, 1) + if need_pad: + embedding_out = F.pad(embedding_out, pad=(self.context_size - 1, 0)) + else: + # During inference time, there is no need to do extra padding + # as we only need one output + if not is_jit_tracing(): + assert embedding_out.size(-1) == self.context_size + embedding_out = self.conv(embedding_out) + embedding_out = embedding_out.permute(0, 2, 1) + embedding_out = F.relu(embedding_out) + return embedding_out diff --git a/egs/librispeech/ASR/incremental_transf/encoder_interface.py b/egs/librispeech/ASR/incremental_transf/encoder_interface.py new file mode 100644 index 000000000..257facce4 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/encoder_interface.py @@ -0,0 +1,43 @@ +# Copyright 2021 Xiaomi Corp. (authors: Fangjun Kuang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +from typing import Tuple + +import torch +import torch.nn as nn + + +class EncoderInterface(nn.Module): + def forward( + self, x: torch.Tensor, x_lens: torch.Tensor + ) -> Tuple[torch.Tensor, torch.Tensor]: + """ + Args: + x: + A tensor of shape (batch_size, input_seq_len, num_features) + containing the input features. + x_lens: + A tensor of shape (batch_size,) containing the number of frames + in `x` before padding. + Returns: + Return a tuple containing two tensors: + - encoder_out, a tensor of (batch_size, out_seq_len, output_dim) + containing unnormalized probabilities, i.e., the output of a + linear layer. + - encoder_out_lens, a tensor of shape (batch_size,) containing + the number of frames in `encoder_out` before padding. + """ + raise NotImplementedError("Please implement it in a subclass") diff --git a/egs/librispeech/ASR/incremental_transf/export.py b/egs/librispeech/ASR/incremental_transf/export.py new file mode 100755 index 000000000..54f656859 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/export.py @@ -0,0 +1,287 @@ +#!/usr/bin/env python3 +# +# Copyright 2021 Xiaomi Corporation (Author: Fangjun Kuang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +# This script converts several saved checkpoints +# to a single one using model averaging. +""" +Usage: +./pruned_transducer_stateless5/export.py \ + --exp-dir ./pruned_transducer_stateless5/exp \ + --bpe-model data/lang_bpe_500/bpe.model \ + --epoch 20 \ + --avg 10 + +It will generate a file exp_dir/pretrained.pt + +To use the generated file with `pruned_transducer_stateless5/decode.py`, +you can do: + + cd /path/to/exp_dir + ln -s pretrained.pt epoch-9999.pt + + cd /path/to/egs/librispeech/ASR + ./pruned_transducer_stateless5/decode.py \ + --exp-dir ./pruned_transducer_stateless5/exp \ + --epoch 9999 \ + --avg 1 \ + --max-duration 600 \ + --decoding-method greedy_search \ + --bpe-model data/lang_bpe_500/bpe.model +""" + +import argparse +import logging +from pathlib import Path + +import sentencepiece as spm +import torch +from scaling_converter import convert_scaled_to_non_scaled +from train import add_model_arguments, get_params, get_transducer_model + +from icefall.checkpoint import ( + average_checkpoints, + average_checkpoints_with_averaged_model, + find_checkpoints, + load_checkpoint, +) +from icefall.utils import str2bool + + +def get_parser(): + parser = argparse.ArgumentParser( + formatter_class=argparse.ArgumentDefaultsHelpFormatter + ) + + parser.add_argument( + "--epoch", + type=int, + default=28, + help="""It specifies the checkpoint to use for averaging. + Note: Epoch counts from 1. + You can specify --avg to use more checkpoints for model averaging.""", + ) + + parser.add_argument( + "--iter", + type=int, + default=0, + help="""If positive, --epoch is ignored and it + will use the checkpoint exp_dir/checkpoint-iter.pt. + You can specify --avg to use more checkpoints for model averaging. + """, + ) + + parser.add_argument( + "--avg", + type=int, + default=15, + help="Number of checkpoints to average. Automatically select " + "consecutive checkpoints before the checkpoint specified by " + "'--epoch' and '--iter'", + ) + + parser.add_argument( + "--use-averaged-model", + type=str2bool, + 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`." + "Actually only the models with epoch number of `epoch-avg` and " + "`epoch` are loaded for averaging. ", + ) + + parser.add_argument( + "--exp-dir", + type=str, + default="pruned_transducer_stateless5/exp", + help="""It specifies the directory where all training related + files, e.g., checkpoints, log, etc, are saved + """, + ) + + parser.add_argument( + "--bpe-model", + type=str, + default="data/lang_bpe_500/bpe.model", + help="Path to the BPE model", + ) + + parser.add_argument( + "--jit", + type=str2bool, + default=False, + help="""True to save a model after applying torch.jit.script. + """, + ) + + parser.add_argument( + "--context-size", + type=int, + default=2, + help="The context size in the decoder. 1 means bigram; 2 means tri-gram", + ) + + parser.add_argument( + "--streaming-model", + type=str2bool, + default=False, + help="""Whether to export a streaming model, if the models in exp-dir + are streaming model, this should be True. + """, + ) + + add_model_arguments(parser) + + return parser + + +def main(): + args = get_parser().parse_args() + args.exp_dir = Path(args.exp_dir) + + params = get_params() + params.update(vars(args)) + + device = torch.device("cpu") + if torch.cuda.is_available(): + device = torch.device("cuda", 0) + + logging.info(f"device: {device}") + + sp = spm.SentencePieceProcessor() + sp.load(params.bpe_model) + + # is defined in local/train_bpe_model.py + params.blank_id = sp.piece_to_id("") + params.vocab_size = sp.get_piece_size() + + if params.streaming_model: + assert params.causal_convolution + + logging.info(params) + + logging.info("About to create model") + model = get_transducer_model(params) + + if not params.use_averaged_model: + if params.iter > 0: + filenames = find_checkpoints(params.exp_dir, iteration=-params.iter)[ + : params.avg + ] + if len(filenames) == 0: + raise ValueError( + f"No checkpoints found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + elif len(filenames) < params.avg: + raise ValueError( + f"Not enough checkpoints ({len(filenames)}) found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + logging.info(f"averaging {filenames}") + model.to(device) + model.load_state_dict(average_checkpoints(filenames, device=device)) + elif params.avg == 1: + load_checkpoint(f"{params.exp_dir}/epoch-{params.epoch}.pt", model) + else: + start = params.epoch - params.avg + 1 + filenames = [] + for i in range(start, params.epoch + 1): + if i >= 1: + filenames.append(f"{params.exp_dir}/epoch-{i}.pt") + logging.info(f"averaging {filenames}") + model.to(device) + model.load_state_dict(average_checkpoints(filenames, device=device)) + else: + if params.iter > 0: + filenames = find_checkpoints(params.exp_dir, iteration=-params.iter)[ + : params.avg + 1 + ] + if len(filenames) == 0: + raise ValueError( + f"No checkpoints found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + elif len(filenames) < params.avg + 1: + raise ValueError( + f"Not enough checkpoints ({len(filenames)}) found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + filename_start = filenames[-1] + filename_end = filenames[0] + logging.info( + "Calculating the averaged model over iteration checkpoints" + f" from {filename_start} (excluded) to {filename_end}" + ) + model.to(device) + model.load_state_dict( + average_checkpoints_with_averaged_model( + filename_start=filename_start, + filename_end=filename_end, + device=device, + ) + ) + else: + assert params.avg > 0, params.avg + start = params.epoch - params.avg + assert start >= 1, start + filename_start = f"{params.exp_dir}/epoch-{start}.pt" + filename_end = f"{params.exp_dir}/epoch-{params.epoch}.pt" + logging.info( + f"Calculating the averaged model over epoch range from " + f"{start} (excluded) to {params.epoch}" + ) + model.to(device) + model.load_state_dict( + average_checkpoints_with_averaged_model( + filename_start=filename_start, + filename_end=filename_end, + device=device, + ) + ) + + model.to("cpu") + model.eval() + + if params.jit: + # We won't use the forward() method of the model in C++, so just ignore + # it here. + # Otherwise, one of its arguments is a ragged tensor and is not + # torch scriptabe. + convert_scaled_to_non_scaled(model, inplace=True) + model.__class__.forward = torch.jit.ignore(model.__class__.forward) + logging.info("Using torch.jit.script") + model = torch.jit.script(model) + filename = params.exp_dir / "cpu_jit.pt" + model.save(str(filename)) + logging.info(f"Saved to {filename}") + else: + logging.info("Not using torch.jit.script") + # Save it using a format so that it can be loaded + # by :func:`load_checkpoint` + filename = params.exp_dir / "pretrained.pt" + torch.save({"model": model.state_dict()}, str(filename)) + logging.info(f"Saved to {filename}") + + +if __name__ == "__main__": + formatter = "%(asctime)s %(levelname)s [%(filename)s:%(lineno)d] %(message)s" + + logging.basicConfig(format=formatter, level=logging.INFO) + main() diff --git a/egs/librispeech/ASR/incremental_transf/joiner.py b/egs/librispeech/ASR/incremental_transf/joiner.py new file mode 100644 index 000000000..1954f4724 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/joiner.py @@ -0,0 +1,69 @@ +# Copyright 2021 Xiaomi Corp. (authors: Fangjun Kuang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import torch +import torch.nn as nn +from scaling import ScaledLinear + +from icefall.utils import is_jit_tracing + + +class Joiner(nn.Module): + def __init__( + self, + encoder_dim: int, + decoder_dim: int, + joiner_dim: int, + vocab_size: int, + ): + super().__init__() + + self.encoder_proj = ScaledLinear(encoder_dim, joiner_dim) + self.decoder_proj = ScaledLinear(decoder_dim, joiner_dim) + self.output_linear = ScaledLinear(joiner_dim, vocab_size) + + def forward( + self, + encoder_out: torch.Tensor, + decoder_out: torch.Tensor, + project_input: bool = True, + ) -> torch.Tensor: + """ + Args: + encoder_out: + Output from the encoder. Its shape is (N, T, s_range, C). + decoder_out: + Output from the decoder. Its shape is (N, T, s_range, C). + project_input: + If true, apply input projections encoder_proj and decoder_proj. + If this is false, it is the user's responsibility to do this + manually. + Returns: + Return a tensor of shape (N, T, s_range, C). + """ + if not is_jit_tracing(): + assert encoder_out.ndim == decoder_out.ndim + assert encoder_out.ndim in (2, 4) + assert encoder_out.shape == decoder_out.shape + + if project_input: + logit = self.encoder_proj(encoder_out) + self.decoder_proj(decoder_out) + else: + logit = encoder_out + decoder_out + + logit = self.output_linear(torch.tanh(logit)) + + return logit diff --git a/egs/librispeech/ASR/incremental_transf/lstmp.py b/egs/librispeech/ASR/incremental_transf/lstmp.py new file mode 100644 index 000000000..dba6eb520 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/lstmp.py @@ -0,0 +1,102 @@ +from typing import Optional, Tuple + +import torch +import torch.nn as nn +import torch.nn.functional as F + + +class LSTMP(nn.Module): + """LSTM with projection. + + PyTorch does not support exporting LSTM with projection to ONNX. + This class reimplements LSTM with projection using basic matrix-matrix + and matrix-vector operations. It is not intended for training. + """ + + def __init__(self, lstm: nn.LSTM): + """ + Args: + lstm: + LSTM with proj_size. We support only uni-directional, + 1-layer LSTM with projection at present. + """ + super().__init__() + assert lstm.bidirectional is False, lstm.bidirectional + assert lstm.num_layers == 1, lstm.num_layers + assert 0 < lstm.proj_size < lstm.hidden_size, ( + lstm.proj_size, + lstm.hidden_size, + ) + + assert lstm.batch_first is False, lstm.batch_first + + state_dict = lstm.state_dict() + + w_ih = state_dict["weight_ih_l0"] + w_hh = state_dict["weight_hh_l0"] + + b_ih = state_dict["bias_ih_l0"] + b_hh = state_dict["bias_hh_l0"] + + w_hr = state_dict["weight_hr_l0"] + self.input_size = lstm.input_size + self.proj_size = lstm.proj_size + self.hidden_size = lstm.hidden_size + + self.w_ih = w_ih + self.w_hh = w_hh + self.b = b_ih + b_hh + self.w_hr = w_hr + + def forward( + self, + input: torch.Tensor, + hx: Optional[Tuple[torch.Tensor, torch.Tensor]] = None, + ) -> Tuple[torch.Tensor, Tuple[torch.Tensor, torch.Tensor]]: + """ + Args: + input: + A tensor of shape [T, N, hidden_size] + hx: + A tuple containing: + - h0: a tensor of shape (1, N, proj_size) + - c0: a tensor of shape (1, N, hidden_size) + Returns: + Return a tuple containing: + - output: a tensor of shape (T, N, proj_size). + - A tuple containing: + - h: a tensor of shape (1, N, proj_size) + - c: a tensor of shape (1, N, hidden_size) + + """ + x_list = input.unbind(dim=0) # We use batch_first=False + + if hx is not None: + h0, c0 = hx + else: + h0 = torch.zeros(1, input.size(1), self.proj_size) + c0 = torch.zeros(1, input.size(1), self.hidden_size) + h0 = h0.squeeze(0) + c0 = c0.squeeze(0) + y_list = [] + for x in x_list: + gates = F.linear(x, self.w_ih, self.b) + F.linear(h0, self.w_hh) + i, f, g, o = gates.chunk(4, dim=1) + + i = i.sigmoid() + f = f.sigmoid() + g = g.tanh() + o = o.sigmoid() + + c = f * c0 + i * g + h = o * c.tanh() + + h = F.linear(h, self.w_hr) + y_list.append(h) + + c0 = c + h0 = h + + y = torch.stack(y_list, dim=0) + + return y, (h0.unsqueeze(0), c0.unsqueeze(0)) diff --git a/egs/librispeech/ASR/incremental_transf/model.py b/egs/librispeech/ASR/incremental_transf/model.py new file mode 100644 index 000000000..272d06c37 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/model.py @@ -0,0 +1,207 @@ +# Copyright 2021 Xiaomi Corp. (authors: Fangjun Kuang, Wei Kang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + + +from typing import Tuple + +import k2 +import torch +import torch.nn as nn +from encoder_interface import EncoderInterface +from scaling import ScaledLinear + +from icefall.utils import add_sos + + +class Transducer(nn.Module): + """It implements https://arxiv.org/pdf/1211.3711.pdf + "Sequence Transduction with Recurrent Neural Networks" + """ + + def __init__( + self, + encoder: EncoderInterface, + decoder: nn.Module, + joiner: nn.Module, + encoder_dim: int, + decoder_dim: int, + joiner_dim: int, + vocab_size: int, + ): + """ + Args: + encoder: + It is the transcription network in the paper. Its accepts + two inputs: `x` of (N, T, encoder_dim) and `x_lens` of shape (N,). + It returns two tensors: `logits` of shape (N, T, encoder_dm) and + `logit_lens` of shape (N,). + decoder: + It is the prediction network in the paper. Its input shape + is (N, U) and its output shape is (N, U, decoder_dim). + It should contain one attribute: `blank_id`. + joiner: + It has two inputs with shapes: (N, T, encoder_dim) and + (N, U, decoder_dim). + Its output shape is (N, T, U, vocab_size). Note that its output + contains unnormalized probs, i.e., not processed by log-softmax. + """ + super().__init__() + assert isinstance(encoder, EncoderInterface), type(encoder) + assert hasattr(decoder, "blank_id") + + self.encoder = encoder + self.decoder = decoder + self.joiner = joiner + + self.simple_am_proj = ScaledLinear(encoder_dim, vocab_size, initial_speed=0.5) + self.simple_lm_proj = ScaledLinear(decoder_dim, vocab_size) + + def forward( + self, + x: torch.Tensor, + x_lens: torch.Tensor, + y: k2.RaggedTensor, + prune_range: int = 5, + am_scale: float = 0.0, + lm_scale: float = 0.0, + warmup: float = 1.0, + reduction: str = "sum", + delay_penalty: float = 0.0, + ) -> Tuple[torch.Tensor, torch.Tensor]: + """ + Args: + x: + A 3-D tensor of shape (N, T, C). + x_lens: + A 1-D tensor of shape (N,). It contains the number of frames in `x` + before padding. + y: + A ragged tensor with 2 axes [utt][label]. It contains labels of each + utterance. + prune_range: + The prune range for rnnt loss, it means how many symbols(context) + we are considering for each frame to compute the loss. + am_scale: + The scale to smooth the loss with am (output of encoder network) + part + lm_scale: + The scale to smooth the loss with lm (output of predictor network) + part + warmup: + A value warmup >= 0 that determines which modules are active, values + warmup > 1 "are fully warmed up" and all modules will be active. + reduction: + "sum" to sum the losses over all utterances in the batch. + "none" to return the loss in a 1-D tensor for each utterance + in the batch. + delay_penalty: + A constant value used to penalize symbol delay, to encourage + streaming models to emit symbols earlier. + See https://github.com/k2-fsa/k2/issues/955 and + https://arxiv.org/pdf/2211.00490.pdf for more details. + Returns: + Returns: + Return the transducer loss. + + Note: + Regarding am_scale & lm_scale, it will make the loss-function one of + the form: + lm_scale * lm_probs + am_scale * am_probs + + (1-lm_scale-am_scale) * combined_probs + """ + assert reduction in ("sum", "none"), reduction + assert x.ndim == 3, x.shape + assert x_lens.ndim == 1, x_lens.shape + assert y.num_axes == 2, y.num_axes + + assert x.size(0) == x_lens.size(0) == y.dim0 + + encoder_out, x_lens = self.encoder(x, x_lens, warmup=warmup) + assert torch.all(x_lens > 0) + + # Now for the decoder, i.e., the prediction network + row_splits = y.shape.row_splits(1) + y_lens = row_splits[1:] - row_splits[:-1] + + blank_id = self.decoder.blank_id + sos_y = add_sos(y, sos_id=blank_id) + + # sos_y_padded: [B, S + 1], start with SOS. + sos_y_padded = sos_y.pad(mode="constant", padding_value=blank_id) + + # decoder_out: [B, S + 1, decoder_dim] + decoder_out = self.decoder(sos_y_padded) + + # Note: y does not start with SOS + # y_padded : [B, S] + y_padded = y.pad(mode="constant", padding_value=0) + + y_padded = y_padded.to(torch.int64) + boundary = torch.zeros((x.size(0), 4), dtype=torch.int64, device=x.device) + boundary[:, 2] = y_lens + boundary[:, 3] = x_lens + + lm = self.simple_lm_proj(decoder_out) + am = self.simple_am_proj(encoder_out) + + with torch.cuda.amp.autocast(enabled=False): + simple_loss, (px_grad, py_grad) = k2.rnnt_loss_smoothed( + lm=lm.float(), + am=am.float(), + symbols=y_padded, + termination_symbol=blank_id, + lm_only_scale=lm_scale, + am_only_scale=am_scale, + boundary=boundary, + reduction=reduction, + delay_penalty=delay_penalty, + return_grad=True, + ) + + # ranges : [B, T, prune_range] + ranges = k2.get_rnnt_prune_ranges( + px_grad=px_grad, + py_grad=py_grad, + boundary=boundary, + s_range=prune_range, + ) + + # am_pruned : [B, T, prune_range, encoder_dim] + # lm_pruned : [B, T, prune_range, decoder_dim] + am_pruned, lm_pruned = k2.do_rnnt_pruning( + am=self.joiner.encoder_proj(encoder_out), + lm=self.joiner.decoder_proj(decoder_out), + ranges=ranges, + ) + + # logits : [B, T, prune_range, vocab_size] + + # project_input=False since we applied the decoder's input projections + # prior to do_rnnt_pruning (this is an optimization for speed). + logits = self.joiner(am_pruned, lm_pruned, project_input=False) + + with torch.cuda.amp.autocast(enabled=False): + pruned_loss = k2.rnnt_loss_pruned( + logits=logits.float(), + symbols=y_padded, + ranges=ranges, + termination_symbol=blank_id, + boundary=boundary, + delay_penalty=delay_penalty, + reduction=reduction, + ) + + return (simple_loss, pruned_loss) diff --git a/egs/librispeech/ASR/incremental_transf/optim.py b/egs/librispeech/ASR/incremental_transf/optim.py new file mode 100644 index 000000000..2d7f557ad --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/optim.py @@ -0,0 +1,320 @@ +# Copyright 2022 Xiaomi Corp. (authors: Daniel Povey) +# +# See ../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + + +from typing import List, Optional, Union + +import torch +from torch.optim import Optimizer + + +class Eve(Optimizer): + r""" + Implements Eve algorithm. This is a modified version of AdamW with a special + way of setting the weight-decay / shrinkage-factor, which is designed to make the + rms of the parameters approach a particular target_rms (default: 0.1). This is + for use with networks with 'scaled' versions of modules (see scaling.py), which + will be close to invariant to the absolute scale on the parameter matrix. + + The original Adam algorithm was proposed in `Adam: A Method for Stochastic Optimization`_. + The AdamW variant was proposed in `Decoupled Weight Decay Regularization`_. + Eve is unpublished so far. + + Arguments: + params (iterable): iterable of parameters to optimize or dicts defining + parameter groups + lr (float, optional): learning rate (default: 1e-3) + betas (Tuple[float, float], optional): coefficients used for computing + running averages of gradient and its square (default: (0.9, 0.999)) + eps (float, optional): term added to the denominator to improve + numerical stability (default: 1e-8) + weight_decay (float, optional): weight decay coefficient (default: 3e-4; + this value means that the weight would decay significantly after + about 3k minibatches. Is not multiplied by learning rate, but + is conditional on RMS-value of parameter being > target_rms. + target_rms (float, optional): target root-mean-square value of + parameters, if they fall below this we will stop applying weight decay. + + + .. _Adam\: A Method for Stochastic Optimization: + https://arxiv.org/abs/1412.6980 + .. _Decoupled Weight Decay Regularization: + https://arxiv.org/abs/1711.05101 + .. _On the Convergence of Adam and Beyond: + https://openreview.net/forum?id=ryQu7f-RZ + """ + + def __init__( + self, + params, + lr=1e-3, + betas=(0.9, 0.98), + eps=1e-8, + weight_decay=1e-3, + target_rms=0.1, + ): + + if not 0.0 <= lr: + raise ValueError("Invalid learning rate: {}".format(lr)) + if not 0.0 <= eps: + raise ValueError("Invalid epsilon value: {}".format(eps)) + if not 0.0 <= betas[0] < 1.0: + raise ValueError("Invalid beta parameter at index 0: {}".format(betas[0])) + if not 0.0 <= betas[1] < 1.0: + raise ValueError("Invalid beta parameter at index 1: {}".format(betas[1])) + if not 0 <= weight_decay <= 0.1: + raise ValueError("Invalid weight_decay value: {}".format(weight_decay)) + if not 0 < target_rms <= 10.0: + raise ValueError("Invalid target_rms value: {}".format(target_rms)) + defaults = dict( + lr=lr, + betas=betas, + eps=eps, + weight_decay=weight_decay, + target_rms=target_rms, + ) + super(Eve, self).__init__(params, defaults) + + def __setstate__(self, state): + super(Eve, self).__setstate__(state) + + @torch.no_grad() + def step(self, closure=None): + """Performs a single optimization step. + + Arguments: + closure (callable, optional): A closure that reevaluates the model + and returns the loss. + """ + loss = None + if closure is not None: + with torch.enable_grad(): + loss = closure() + + for group in self.param_groups: + for p in group["params"]: + if p.grad is None: + continue + + # Perform optimization step + grad = p.grad + if grad.is_sparse: + raise RuntimeError("AdamW does not support sparse gradients") + + state = self.state[p] + + # State initialization + if len(state) == 0: + state["step"] = 0 + # Exponential moving average of gradient values + state["exp_avg"] = torch.zeros_like( + p, memory_format=torch.preserve_format + ) + # Exponential moving average of squared gradient values + state["exp_avg_sq"] = torch.zeros_like( + p, memory_format=torch.preserve_format + ) + + exp_avg, exp_avg_sq = state["exp_avg"], state["exp_avg_sq"] + + beta1, beta2 = group["betas"] + + state["step"] += 1 + bias_correction1 = 1 - beta1 ** state["step"] + bias_correction2 = 1 - beta2 ** state["step"] + + # Decay the first and second moment running average coefficient + exp_avg.mul_(beta1).add_(grad, alpha=1 - beta1) + exp_avg_sq.mul_(beta2).addcmul_(grad, grad, value=1 - beta2) + denom = (exp_avg_sq.sqrt() * (bias_correction2**-0.5)).add_( + group["eps"] + ) + + step_size = group["lr"] / bias_correction1 + target_rms = group["target_rms"] + weight_decay = group["weight_decay"] + + if p.numel() > 1: + # avoid applying this weight-decay on "scaling factors" + # (which are scalar). + is_above_target_rms = p.norm() > (target_rms * (p.numel() ** 0.5)) + p.mul_(1 - (weight_decay * is_above_target_rms)) + p.addcdiv_(exp_avg, denom, value=-step_size) + + # Constrain the range of scalar weights + if p.numel() == 1: + p.clamp_(min=-10, max=2) + + return loss + + +class LRScheduler(object): + """ + Base-class for learning rate schedulers where the learning-rate depends on both the + batch and the epoch. + """ + + def __init__(self, optimizer: Optimizer, verbose: bool = False): + # Attach optimizer + if not isinstance(optimizer, Optimizer): + raise TypeError("{} is not an Optimizer".format(type(optimizer).__name__)) + self.optimizer = optimizer + self.verbose = verbose + + for group in optimizer.param_groups: + group.setdefault("initial_lr", group["lr"]) + + self.base_lrs = [group["initial_lr"] for group in optimizer.param_groups] + + self.epoch = 0 + self.batch = 0 + + def state_dict(self): + """Returns the state of the scheduler as a :class:`dict`. + + It contains an entry for every variable in self.__dict__ which + is not the optimizer. + """ + return { + "base_lrs": self.base_lrs, + "epoch": self.epoch, + "batch": self.batch, + } + + def load_state_dict(self, state_dict): + """Loads the schedulers state. + + Args: + state_dict (dict): scheduler state. Should be an object returned + from a call to :meth:`state_dict`. + """ + self.__dict__.update(state_dict) + + def get_last_lr(self) -> List[float]: + """Return last computed learning rate by current scheduler. Will be a list of float.""" + return self._last_lr + + def get_lr(self): + # Compute list of learning rates from self.epoch and self.batch and + # self.base_lrs; this must be overloaded by the user. + # e.g. return [some_formula(self.batch, self.epoch, base_lr) for base_lr in self.base_lrs ] + raise NotImplementedError + + def step_batch(self, batch: Optional[int] = None) -> None: + # Step the batch index, or just set it. If `batch` is specified, it + # must be the batch index from the start of training, i.e. summed over + # all epochs. + # You can call this in any order; if you don't provide 'batch', it should + # of course be called once per batch. + if batch is not None: + self.batch = batch + else: + self.batch = self.batch + 1 + self._set_lrs() + + def step_epoch(self, epoch: Optional[int] = None): + # Step the epoch index, or just set it. If you provide the 'epoch' arg, + # you should call this at the start of the epoch; if you don't provide the 'epoch' + # arg, you should call it at the end of the epoch. + if epoch is not None: + self.epoch = epoch + else: + self.epoch = self.epoch + 1 + self._set_lrs() + + def _set_lrs(self): + values = self.get_lr() + assert len(values) == len(self.optimizer.param_groups) + + for i, data in enumerate(zip(self.optimizer.param_groups, values)): + param_group, lr = data + param_group["lr"] = lr + self.print_lr(self.verbose, i, lr) + self._last_lr = [group["lr"] for group in self.optimizer.param_groups] + + def print_lr(self, is_verbose, group, lr): + """Display the current learning rate.""" + if is_verbose: + print( + f"Epoch={self.epoch}, batch={self.batch}: adjusting learning rate" + f" of group {group} to {lr:.4e}." + ) + + +class Eden(LRScheduler): + """ + Eden scheduler. + lr = initial_lr * (((batch**2 + lr_batches**2) / lr_batches**2) ** -0.25 * + (((epoch**2 + lr_epochs**2) / lr_epochs**2) ** -0.25)) + + E.g. suggest initial-lr = 0.003 (passed to optimizer). + + Args: + optimizer: the optimizer to change the learning rates on + lr_batches: the number of batches after which we start significantly + decreasing the learning rate, suggest 5000. + lr_epochs: the number of epochs after which we start significantly + decreasing the learning rate, suggest 6 if you plan to do e.g. + 20 to 40 epochs, but may need smaller number if dataset is huge + and you will do few epochs. + """ + + def __init__( + self, + optimizer: Optimizer, + lr_batches: Union[int, float], + lr_epochs: Union[int, float], + verbose: bool = False, + ): + super(Eden, self).__init__(optimizer, verbose) + self.lr_batches = lr_batches + self.lr_epochs = lr_epochs + + def get_lr(self): + factor = ( + (self.batch**2 + self.lr_batches**2) / self.lr_batches**2 + ) ** -0.25 * ( + ((self.epoch**2 + self.lr_epochs**2) / self.lr_epochs**2) ** -0.25 + ) + return [x * factor for x in self.base_lrs] + + +def _test_eden(): + m = torch.nn.Linear(100, 100) + optim = Eve(m.parameters(), lr=0.003) + + scheduler = Eden(optim, lr_batches=30, lr_epochs=2, verbose=True) + + for epoch in range(10): + scheduler.step_epoch(epoch) # sets epoch to `epoch` + + for step in range(20): + x = torch.randn(200, 100).detach() + x.requires_grad = True + y = m(x) + dy = torch.randn(200, 100).detach() + f = (y * dy).sum() + f.backward() + + optim.step() + scheduler.step_batch() + optim.zero_grad() + print("last lr = ", scheduler.get_last_lr()) + print("state dict = ", scheduler.state_dict()) + + +if __name__ == "__main__": + _test_eden() diff --git a/egs/librispeech/ASR/incremental_transf/pretrained.py b/egs/librispeech/ASR/incremental_transf/pretrained.py new file mode 100755 index 000000000..74a2210c3 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/pretrained.py @@ -0,0 +1,344 @@ +#!/usr/bin/env python3 +# Copyright 2021 Xiaomi Corp. (authors: Fangjun Kuang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +""" +Usage: + +(1) greedy search +./pruned_transducer_stateless5/pretrained.py \ + --checkpoint ./pruned_transducer_stateless5/exp/pretrained.pt \ + --bpe-model ./data/lang_bpe_500/bpe.model \ + --method greedy_search \ + /path/to/foo.wav \ + /path/to/bar.wav + +(2) beam search +./pruned_transducer_stateless5/pretrained.py \ + --checkpoint ./pruned_transducer_stateless5/exp/pretrained.pt \ + --bpe-model ./data/lang_bpe_500/bpe.model \ + --method beam_search \ + --beam-size 4 \ + /path/to/foo.wav \ + /path/to/bar.wav + +(3) modified beam search +./pruned_transducer_stateless5/pretrained.py \ + --checkpoint ./pruned_transducer_stateless5/exp/pretrained.pt \ + --bpe-model ./data/lang_bpe_500/bpe.model \ + --method modified_beam_search \ + --beam-size 4 \ + /path/to/foo.wav \ + /path/to/bar.wav + +(4) fast beam search +./pruned_transducer_stateless5/pretrained.py \ + --checkpoint ./pruned_transducer_stateless5/exp/pretrained.pt \ + --bpe-model ./data/lang_bpe_500/bpe.model \ + --method fast_beam_search \ + --beam-size 4 \ + /path/to/foo.wav \ + /path/to/bar.wav + +You can also use `./pruned_transducer_stateless5/exp/epoch-xx.pt`. + +Note: ./pruned_transducer_stateless5/exp/pretrained.pt is generated by +./pruned_transducer_stateless5/export.py +""" + + +import argparse +import logging +import math +from typing import List + +import k2 +import kaldifeat +import sentencepiece as spm +import torch +import torchaudio +from beam_search import ( + beam_search, + fast_beam_search_one_best, + greedy_search, + greedy_search_batch, + modified_beam_search, +) +from torch.nn.utils.rnn import pad_sequence +from train import add_model_arguments, get_params, get_transducer_model + + +def get_parser(): + parser = argparse.ArgumentParser( + formatter_class=argparse.ArgumentDefaultsHelpFormatter + ) + + parser.add_argument( + "--checkpoint", + type=str, + required=True, + help="Path to the checkpoint. " + "The checkpoint is assumed to be saved by " + "icefall.checkpoint.save_checkpoint().", + ) + + parser.add_argument( + "--bpe-model", + type=str, + help="""Path to bpe.model.""", + ) + + parser.add_argument( + "--method", + type=str, + default="greedy_search", + help="""Possible values are: + - greedy_search + - beam_search + - modified_beam_search + - fast_beam_search + """, + ) + + parser.add_argument( + "sound_files", + type=str, + nargs="+", + help="The input sound file(s) to transcribe. " + "Supported formats are those supported by torchaudio.load(). " + "For example, wav and flac are supported. " + "The sample rate has to be 16kHz.", + ) + + parser.add_argument( + "--sample-rate", + type=int, + default=16000, + help="The sample rate of the input sound file", + ) + + parser.add_argument( + "--beam-size", + type=int, + default=4, + help="""An integer indicating how many candidates we will keep for each + frame. Used only when --method is beam_search or + modified_beam_search.""", + ) + + parser.add_argument( + "--beam", + type=float, + default=4, + 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 --method is fast_beam_search""", + ) + + parser.add_argument( + "--max-contexts", + type=int, + default=4, + help="""Used only when --method is fast_beam_search""", + ) + + parser.add_argument( + "--max-states", + type=int, + default=8, + help="""Used only when --method is fast_beam_search""", + ) + + parser.add_argument( + "--context-size", + type=int, + default=2, + help="The context size in the decoder. 1 means bigram; 2 means tri-gram", + ) + parser.add_argument( + "--max-sym-per-frame", + type=int, + default=1, + help="""Maximum number of symbols per frame. Used only when + --method is greedy_search. + """, + ) + + add_model_arguments(parser) + + return parser + + +def read_sound_files( + filenames: List[str], expected_sample_rate: float +) -> List[torch.Tensor]: + """Read a list of sound files into a list 1-D float32 torch tensors. + Args: + filenames: + A list of sound filenames. + expected_sample_rate: + The expected sample rate of the sound files. + Returns: + Return a list of 1-D float32 torch tensors. + """ + ans = [] + for f in filenames: + wave, sample_rate = torchaudio.load(f) + assert ( + sample_rate == expected_sample_rate + ), f"expected sample rate: {expected_sample_rate}. Given: {sample_rate}" + # We use only the first channel + ans.append(wave[0]) + return ans + + +@torch.no_grad() +def main(): + parser = get_parser() + args = parser.parse_args() + + params = get_params() + + params.update(vars(args)) + + sp = spm.SentencePieceProcessor() + sp.load(params.bpe_model) + + # is defined in local/train_bpe_model.py + params.blank_id = sp.piece_to_id("") + params.unk_id = sp.piece_to_id("") + params.vocab_size = sp.get_piece_size() + + logging.info(f"{params}") + + device = torch.device("cpu") + if torch.cuda.is_available(): + device = torch.device("cuda", 0) + + logging.info(f"device: {device}") + + logging.info("Creating model") + model = get_transducer_model(params) + + num_param = sum([p.numel() for p in model.parameters()]) + logging.info(f"Number of model parameters: {num_param}") + + checkpoint = torch.load(args.checkpoint, map_location="cpu") + model.load_state_dict(checkpoint["model"], strict=False) + model.to(device) + model.eval() + model.device = device + + logging.info("Constructing Fbank computer") + opts = kaldifeat.FbankOptions() + opts.device = device + opts.frame_opts.dither = 0 + opts.frame_opts.snip_edges = False + opts.frame_opts.samp_freq = params.sample_rate + opts.mel_opts.num_bins = params.feature_dim + + fbank = kaldifeat.Fbank(opts) + + logging.info(f"Reading sound files: {params.sound_files}") + waves = read_sound_files( + filenames=params.sound_files, expected_sample_rate=params.sample_rate + ) + waves = [w.to(device) for w in waves] + + logging.info("Decoding started") + features = fbank(waves) + feature_lengths = [f.size(0) for f in features] + + features = pad_sequence(features, batch_first=True, padding_value=math.log(1e-10)) + + feature_lengths = torch.tensor(feature_lengths, device=device) + + encoder_out, encoder_out_lens = model.encoder(x=features, x_lens=feature_lengths) + + num_waves = encoder_out.size(0) + hyps = [] + msg = f"Using {params.method}" + if params.method == "beam_search": + msg += f" with beam size {params.beam_size}" + logging.info(msg) + + if params.method == "fast_beam_search": + decoding_graph = k2.trivial_graph(params.vocab_size - 1, device=device) + hyp_tokens = fast_beam_search_one_best( + 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, + ) + for hyp in sp.decode(hyp_tokens): + hyps.append(hyp.split()) + elif params.method == "modified_beam_search": + hyp_tokens = modified_beam_search( + model=model, + encoder_out=encoder_out, + encoder_out_lens=encoder_out_lens, + beam=params.beam_size, + ) + + for hyp in sp.decode(hyp_tokens): + hyps.append(hyp.split()) + elif params.method == "greedy_search" and params.max_sym_per_frame == 1: + hyp_tokens = greedy_search_batch( + model=model, + encoder_out=encoder_out, + encoder_out_lens=encoder_out_lens, + ) + for hyp in sp.decode(hyp_tokens): + hyps.append(hyp.split()) + else: + for i in range(num_waves): + # fmt: off + encoder_out_i = encoder_out[i:i+1, :encoder_out_lens[i]] + # fmt: on + if params.method == "greedy_search": + hyp = greedy_search( + model=model, + encoder_out=encoder_out_i, + max_sym_per_frame=params.max_sym_per_frame, + ) + elif params.method == "beam_search": + hyp = beam_search( + model=model, + encoder_out=encoder_out_i, + beam=params.beam_size, + ) + else: + raise ValueError(f"Unsupported method: {params.method}") + + hyps.append(sp.decode(hyp).split()) + + s = "\n" + for filename, hyp in zip(params.sound_files, hyps): + words = " ".join(hyp) + s += f"{filename}:\n{words}\n\n" + logging.info(s) + + logging.info("Decoding Done") + + +if __name__ == "__main__": + formatter = "%(asctime)s %(levelname)s [%(filename)s:%(lineno)d] %(message)s" + + logging.basicConfig(format=formatter, level=logging.INFO) + main() diff --git a/egs/librispeech/ASR/incremental_transf/scaling.py b/egs/librispeech/ASR/incremental_transf/scaling.py new file mode 100644 index 000000000..963ebdc2d --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/scaling.py @@ -0,0 +1,1015 @@ +# Copyright 2022 Xiaomi Corp. (authors: Daniel Povey, Zengwei Yao) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + + +import collections +import random +from itertools import repeat +from typing import Optional, Tuple + +import torch +import torch.backends.cudnn.rnn as rnn +import torch.nn as nn +from torch import _VF, Tensor + +from icefall.utils import is_jit_tracing + + +def _ntuple(n): + def parse(x): + if isinstance(x, collections.Iterable): + return x + return tuple(repeat(x, n)) + + return parse + + +_single = _ntuple(1) +_pair = _ntuple(2) + + +class ActivationBalancerFunction(torch.autograd.Function): + @staticmethod + def forward( + ctx, + x: Tensor, + channel_dim: int, + min_positive: float, # e.g. 0.05 + max_positive: float, # e.g. 0.95 + max_factor: float, # e.g. 0.01 + min_abs: float, # e.g. 0.2 + max_abs: float, # e.g. 100.0 + ) -> Tensor: + if x.requires_grad: + if channel_dim < 0: + channel_dim += x.ndim + + # sum_dims = [d for d in range(x.ndim) if d != channel_dim] + # The above line is not torch scriptable for torch 1.6.0 + # torch.jit.frontend.NotSupportedError: comprehension ifs not supported yet: # noqa + sum_dims = [] + for d in range(x.ndim): + if d != channel_dim: + sum_dims.append(d) + + xgt0 = x > 0 + proportion_positive = torch.mean( + xgt0.to(x.dtype), dim=sum_dims, keepdim=True + ) + factor1 = ( + (min_positive - proportion_positive).relu() + * (max_factor / min_positive) + if min_positive != 0.0 + else 0.0 + ) + factor2 = ( + (proportion_positive - max_positive).relu() + * (max_factor / (max_positive - 1.0)) + if max_positive != 1.0 + else 0.0 + ) + factor = factor1 + factor2 + if isinstance(factor, float): + factor = torch.zeros_like(proportion_positive) + + mean_abs = torch.mean(x.abs(), dim=sum_dims, keepdim=True) + below_threshold = mean_abs < min_abs + above_threshold = mean_abs > max_abs + + ctx.save_for_backward(factor, xgt0, below_threshold, above_threshold) + ctx.max_factor = max_factor + ctx.sum_dims = sum_dims + return x + + @staticmethod + def backward( + ctx, x_grad: Tensor + ) -> Tuple[Tensor, None, None, None, None, None, None]: + factor, xgt0, below_threshold, above_threshold = ctx.saved_tensors + dtype = x_grad.dtype + scale_factor = ( + (below_threshold.to(dtype) - above_threshold.to(dtype)) + * (xgt0.to(dtype) - 0.5) + * (ctx.max_factor * 2.0) + ) + + neg_delta_grad = x_grad.abs() * (factor + scale_factor) + return x_grad - neg_delta_grad, None, None, None, None, None, None + + +class GradientFilterFunction(torch.autograd.Function): + @staticmethod + def forward( + ctx, + x: Tensor, + batch_dim: int, # e.g., 1 + threshold: float, # e.g., 10.0 + *params: Tensor, # module parameters + ) -> Tuple[Tensor, ...]: + if x.requires_grad: + if batch_dim < 0: + batch_dim += x.ndim + ctx.batch_dim = batch_dim + ctx.threshold = threshold + return (x,) + params + + @staticmethod + def backward( + ctx, + x_grad: Tensor, + *param_grads: Tensor, + ) -> Tuple[Tensor, ...]: + eps = 1.0e-20 + dim = ctx.batch_dim + norm_dims = [d for d in range(x_grad.ndim) if d != dim] + norm_of_batch = (x_grad**2).mean(dim=norm_dims, keepdim=True).sqrt() + median_norm = norm_of_batch.median() + + cutoff = median_norm * ctx.threshold + inv_mask = (cutoff + norm_of_batch) / (cutoff + eps) + mask = 1.0 / (inv_mask + eps) + x_grad = x_grad * mask + + avg_mask = 1.0 / (inv_mask.mean() + eps) + param_grads = [avg_mask * g for g in param_grads] + + return (x_grad, None, None) + tuple(param_grads) + + +class GradientFilter(torch.nn.Module): + """This is used to filter out elements that have extremely large gradients + in batch and the module parameters with soft masks. + + Args: + batch_dim (int): + The batch dimension. + threshold (float): + For each element in batch, its gradient will be + filtered out if the gradient norm is larger than + `grad_norm_threshold * median`, where `median` is the median + value of gradient norms of all elememts in batch. + """ + + def __init__(self, batch_dim: int = 1, threshold: float = 10.0): + super(GradientFilter, self).__init__() + self.batch_dim = batch_dim + self.threshold = threshold + + def forward(self, x: Tensor, *params: Tensor) -> Tuple[Tensor, ...]: + if torch.jit.is_scripting() or is_jit_tracing(): + return (x,) + params + else: + return GradientFilterFunction.apply( + x, + self.batch_dim, + self.threshold, + *params, + ) + + +class BasicNorm(torch.nn.Module): + """ + This is intended to be a simpler, and hopefully cheaper, replacement for + LayerNorm. The observation this is based on, is that Transformer-type + networks, especially with pre-norm, sometimes seem to set one of the + feature dimensions to a large constant value (e.g. 50), which "defeats" + the LayerNorm because the output magnitude is then not strongly dependent + on the other (useful) features. Presumably the weight and bias of the + LayerNorm are required to allow it to do this. + + So the idea is to introduce this large constant value as an explicit + parameter, that takes the role of the "eps" in LayerNorm, so the network + doesn't have to do this trick. We make the "eps" learnable. + + Args: + num_channels: the number of channels, e.g. 512. + channel_dim: the axis/dimension corresponding to the channel, + interprted as an offset from the input's ndim if negative. + shis is NOT the num_channels; it should typically be one of + {-2, -1, 0, 1, 2, 3}. + eps: the initial "epsilon" that we add as ballast in: + scale = ((input_vec**2).mean() + epsilon)**-0.5 + Note: our epsilon is actually large, but we keep the name + to indicate the connection with conventional LayerNorm. + learn_eps: if true, we learn epsilon; if false, we keep it + at the initial value. + """ + + def __init__( + self, + num_channels: int, + channel_dim: int = -1, # CAUTION: see documentation. + eps: float = 0.25, + learn_eps: bool = True, + ) -> None: + super(BasicNorm, self).__init__() + self.num_channels = num_channels + self.channel_dim = channel_dim + if learn_eps: + self.eps = nn.Parameter(torch.tensor(eps).log().detach()) + else: + self.register_buffer("eps", torch.tensor(eps).log().detach()) + + def forward(self, x: Tensor) -> Tensor: + if not is_jit_tracing(): + assert x.shape[self.channel_dim] == self.num_channels + scales = ( + torch.mean(x**2, dim=self.channel_dim, keepdim=True) + self.eps.exp() + ) ** -0.5 + return x * scales + + +class ScaledLinear(nn.Linear): + """ + A modified version of nn.Linear where the parameters are scaled before + use, via: + weight = self.weight * self.weight_scale.exp() + bias = self.bias * self.bias_scale.exp() + + Args: + Accepts the standard args and kwargs that nn.Linear accepts + e.g. in_features, out_features, bias=False. + + initial_scale: you can override this if you want to increase + or decrease the initial magnitude of the module's output + (affects the initialization of weight_scale and bias_scale). + Another option, if you want to do something like this, is + to re-initialize the parameters. + initial_speed: this affects how fast the parameter will + learn near the start of training; you can set it to a + value less than one if you suspect that a module + is contributing to instability near the start of training. + Nnote: regardless of the use of this option, it's best to + use schedulers like Noam that have a warm-up period. + Alternatively you can set it to more than 1 if you want it to + initially train faster. Must be greater than 0. + """ + + def __init__( + self, + *args, + initial_scale: float = 1.0, + initial_speed: float = 1.0, + **kwargs, + ): + super(ScaledLinear, self).__init__(*args, **kwargs) + initial_scale = torch.tensor(initial_scale).log() + self.weight_scale = nn.Parameter(initial_scale.clone().detach()) + if self.bias is not None: + self.bias_scale = nn.Parameter(initial_scale.clone().detach()) + else: + self.register_parameter("bias_scale", None) + + self._reset_parameters( + initial_speed + ) # Overrides the reset_parameters in nn.Linear + + def _reset_parameters(self, initial_speed: float): + std = 0.1 / initial_speed + a = (3**0.5) * std + nn.init.uniform_(self.weight, -a, a) + if self.bias is not None: + nn.init.constant_(self.bias, 0.0) + fan_in = self.weight.shape[1] * self.weight[0][0].numel() + scale = fan_in**-0.5 # 1/sqrt(fan_in) + with torch.no_grad(): + self.weight_scale += torch.tensor(scale / std).log() + + def get_weight(self): + return self.weight * self.weight_scale.exp() + + def get_bias(self): + if self.bias is None or self.bias_scale is None: + return None + else: + return self.bias * self.bias_scale.exp() + + def forward(self, input: Tensor) -> Tensor: + return torch.nn.functional.linear(input, self.get_weight(), self.get_bias()) + + +class ScaledConv1d(nn.Conv1d): + # See docs for ScaledLinear + def __init__( + self, + *args, + initial_scale: float = 1.0, + initial_speed: float = 1.0, + **kwargs, + ): + super(ScaledConv1d, self).__init__(*args, **kwargs) + initial_scale = torch.tensor(initial_scale).log() + + self.bias_scale: Optional[nn.Parameter] # for torchscript + + self.weight_scale = nn.Parameter(initial_scale.clone().detach()) + if self.bias is not None: + self.bias_scale = nn.Parameter(initial_scale.clone().detach()) + else: + self.register_parameter("bias_scale", None) + self._reset_parameters( + initial_speed + ) # Overrides the reset_parameters in base class + + def _reset_parameters(self, initial_speed: float): + std = 0.1 / initial_speed + a = (3**0.5) * std + nn.init.uniform_(self.weight, -a, a) + if self.bias is not None: + nn.init.constant_(self.bias, 0.0) + fan_in = self.weight.shape[1] * self.weight[0][0].numel() + scale = fan_in**-0.5 # 1/sqrt(fan_in) + with torch.no_grad(): + self.weight_scale += torch.tensor(scale / std).log() + + def get_weight(self): + return self.weight * self.weight_scale.exp() + + def get_bias(self): + bias = self.bias + bias_scale = self.bias_scale + if bias is None or bias_scale is None: + return None + else: + return bias * bias_scale.exp() + + def forward(self, input: Tensor) -> Tensor: + F = torch.nn.functional + if self.padding_mode != "zeros": + return F.conv1d( + F.pad( + input, + self._reversed_padding_repeated_twice, + mode=self.padding_mode, + ), + self.get_weight(), + self.get_bias(), + self.stride, + (0,), + self.dilation, + self.groups, + ) + return F.conv1d( + input, + self.get_weight(), + self.get_bias(), + self.stride, + self.padding, + self.dilation, + self.groups, + ) + + +class ScaledConv2d(nn.Conv2d): + # See docs for ScaledLinear + def __init__( + self, + *args, + initial_scale: float = 1.0, + initial_speed: float = 1.0, + **kwargs, + ): + super(ScaledConv2d, self).__init__(*args, **kwargs) + initial_scale = torch.tensor(initial_scale).log() + self.weight_scale = nn.Parameter(initial_scale.clone().detach()) + if self.bias is not None: + self.bias_scale = nn.Parameter(initial_scale.clone().detach()) + else: + self.register_parameter("bias_scale", None) + self._reset_parameters( + initial_speed + ) # Overrides the reset_parameters in base class + + def _reset_parameters(self, initial_speed: float): + std = 0.1 / initial_speed + a = (3**0.5) * std + nn.init.uniform_(self.weight, -a, a) + if self.bias is not None: + nn.init.constant_(self.bias, 0.0) + fan_in = self.weight.shape[1] * self.weight[0][0].numel() + scale = fan_in**-0.5 # 1/sqrt(fan_in) + with torch.no_grad(): + self.weight_scale += torch.tensor(scale / std).log() + + def get_weight(self): + return self.weight * self.weight_scale.exp() + + def get_bias(self): + # see https://github.com/pytorch/pytorch/issues/24135 + bias = self.bias + bias_scale = self.bias_scale + if bias is None or bias_scale is None: + return None + else: + return bias * bias_scale.exp() + + def _conv_forward(self, input, weight): + F = torch.nn.functional + if self.padding_mode != "zeros": + return F.conv2d( + F.pad( + input, + self._reversed_padding_repeated_twice, + mode=self.padding_mode, + ), + weight, + self.get_bias(), + self.stride, + (0, 0), + self.dilation, + self.groups, + ) + return F.conv2d( + input, + weight, + self.get_bias(), + self.stride, + self.padding, + self.dilation, + self.groups, + ) + + def forward(self, input: Tensor) -> Tensor: + return self._conv_forward(input, self.get_weight()) + + +class ScaledLSTM(nn.LSTM): + # See docs for ScaledLinear. + # This class implements LSTM with scaling mechanism, using `torch._VF.lstm` + # Please refer to https://github.com/pytorch/pytorch/blob/master/torch/nn/modules/rnn.py + def __init__( + self, + *args, + initial_scale: float = 1.0, + initial_speed: float = 1.0, + grad_norm_threshold: float = 10.0, + **kwargs, + ): + if "bidirectional" in kwargs: + assert kwargs["bidirectional"] is False + super(ScaledLSTM, self).__init__(*args, **kwargs) + initial_scale = torch.tensor(initial_scale).log() + self._scales_names = [] + self._scales = [] + for name in self._flat_weights_names: + scale_name = name + "_scale" + self._scales_names.append(scale_name) + param = nn.Parameter(initial_scale.clone().detach()) + setattr(self, scale_name, param) + self._scales.append(param) + + self.grad_filter = GradientFilter(batch_dim=1, threshold=grad_norm_threshold) + + self._reset_parameters( + initial_speed + ) # Overrides the reset_parameters in base class + + def _reset_parameters(self, initial_speed: float): + std = 0.1 / initial_speed + a = (3**0.5) * std + scale = self.hidden_size**-0.5 + v = scale / std + for idx, name in enumerate(self._flat_weights_names): + if "weight" in name: + nn.init.uniform_(self._flat_weights[idx], -a, a) + with torch.no_grad(): + self._scales[idx] += torch.tensor(v).log() + elif "bias" in name: + nn.init.constant_(self._flat_weights[idx], 0.0) + + def _flatten_parameters(self, flat_weights) -> None: + """Resets parameter data pointer so that they can use faster code paths. + + Right now, this works only if the module is on the GPU and cuDNN is enabled. + Otherwise, it's a no-op. + + This function is modified from https://github.com/pytorch/pytorch/blob/master/torch/nn/modules/rnn.py # noqa + """ + # Short-circuits if _flat_weights is only partially instantiated + if len(flat_weights) != len(self._flat_weights_names): + return + + for w in flat_weights: + if not isinstance(w, Tensor): + return + # Short-circuits if any tensor in flat_weights is not acceptable to cuDNN + # or the tensors in flat_weights are of different dtypes + + first_fw = flat_weights[0] + dtype = first_fw.dtype + for fw in flat_weights: + if ( + not isinstance(fw.data, Tensor) + or not (fw.data.dtype == dtype) + or not fw.data.is_cuda + or not torch.backends.cudnn.is_acceptable(fw.data) + ): + return + + # If any parameters alias, we fall back to the slower, copying code path. This is + # a sufficient check, because overlapping parameter buffers that don't completely + # alias would break the assumptions of the uniqueness check in + # Module.named_parameters(). + unique_data_ptrs = set(p.data_ptr() for p in flat_weights) + if len(unique_data_ptrs) != len(flat_weights): + return + + with torch.cuda.device_of(first_fw): + + # Note: no_grad() is necessary since _cudnn_rnn_flatten_weight is + # an inplace operation on self._flat_weights + with torch.no_grad(): + if torch._use_cudnn_rnn_flatten_weight(): + num_weights = 4 if self.bias else 2 + if self.proj_size > 0: + num_weights += 1 + torch._cudnn_rnn_flatten_weight( + flat_weights, + num_weights, + self.input_size, + rnn.get_cudnn_mode(self.mode), + self.hidden_size, + self.proj_size, + self.num_layers, + self.batch_first, + bool(self.bidirectional), + ) + + def _get_flat_weights(self): + """Get scaled weights, and resets their data pointer.""" + flat_weights = [] + for idx in range(len(self._flat_weights_names)): + flat_weights.append(self._flat_weights[idx] * self._scales[idx].exp()) + self._flatten_parameters(flat_weights) + return flat_weights + + def forward(self, input: Tensor, hx: Optional[Tuple[Tensor, Tensor]] = None): + # This function is modified from https://github.com/pytorch/pytorch/blob/master/torch/nn/modules/rnn.py # noqa + # The change for calling `_VF.lstm()` is: + # self._flat_weights -> self._get_flat_weights() + if hx is None: + h_zeros = torch.zeros( + self.num_layers, + input.size(1), + self.proj_size if self.proj_size > 0 else self.hidden_size, + dtype=input.dtype, + device=input.device, + ) + c_zeros = torch.zeros( + self.num_layers, + input.size(1), + self.hidden_size, + dtype=input.dtype, + device=input.device, + ) + hx = (h_zeros, c_zeros) + + self.check_forward_args(input, hx, None) + + flat_weights = self._get_flat_weights() + input, *flat_weights = self.grad_filter(input, *flat_weights) + + result = _VF.lstm( + input, + hx, + flat_weights, + self.bias, + self.num_layers, + self.dropout, + self.training, + self.bidirectional, + self.batch_first, + ) + + output = result[0] + hidden = result[1:] + return output, hidden + + +class ActivationBalancer(torch.nn.Module): + """ + Modifies the backpropped derivatives of a function to try to encourage, for + each channel, that it is positive at least a proportion `threshold` of the + time. It does this by multiplying negative derivative values by up to + (1+max_factor), and positive derivative values by up to (1-max_factor), + interpolated from 1 at the threshold to those extremal values when none + of the inputs are positive. + + + Args: + channel_dim: the dimension/axis corresponding to the channel, e.g. + -1, 0, 1, 2; will be interpreted as an offset from x.ndim if negative. + min_positive: the minimum, per channel, of the proportion of the time + that (x > 0), below which we start to modify the derivatives. + max_positive: the maximum, per channel, of the proportion of the time + that (x > 0), above which we start to modify the derivatives. + max_factor: the maximum factor by which we modify the derivatives for + either the sign constraint or the magnitude constraint; + e.g. with max_factor=0.02, the the derivatives would be multiplied by + values in the range [0.98..1.02]. + min_abs: the minimum average-absolute-value per channel, which + we allow, before we start to modify the derivatives to prevent + this. + max_abs: the maximum average-absolute-value per channel, which + we allow, before we start to modify the derivatives to prevent + this. + balance_prob: the probability to apply the ActivationBalancer. + """ + + def __init__( + self, + channel_dim: int, + min_positive: float = 0.05, + max_positive: float = 0.95, + max_factor: float = 0.01, + min_abs: float = 0.2, + max_abs: float = 100.0, + balance_prob: float = 0.25, + ): + super(ActivationBalancer, self).__init__() + self.channel_dim = channel_dim + self.min_positive = min_positive + self.max_positive = max_positive + self.max_factor = max_factor + self.min_abs = min_abs + self.max_abs = max_abs + assert 0 < balance_prob <= 1, balance_prob + self.balance_prob = balance_prob + + def forward(self, x: Tensor) -> Tensor: + if random.random() >= self.balance_prob: + return x + + return ActivationBalancerFunction.apply( + x, + self.channel_dim, + self.min_positive, + self.max_positive, + self.max_factor / self.balance_prob, + self.min_abs, + self.max_abs, + ) + + +class DoubleSwishFunction(torch.autograd.Function): + """ + double_swish(x) = x * torch.sigmoid(x-1) + This is a definition, originally motivated by its close numerical + similarity to swish(swish(x)), where swish(x) = x * sigmoid(x). + + Memory-efficient derivative computation: + double_swish(x) = x * s, where s(x) = torch.sigmoid(x-1) + double_swish'(x) = d/dx double_swish(x) = x * s'(x) + x' * s(x) = x * s'(x) + s(x). + Now, s'(x) = s(x) * (1-s(x)). + double_swish'(x) = x * s'(x) + s(x). + = x * s(x) * (1-s(x)) + s(x). + = double_swish(x) * (1-s(x)) + s(x) + ... so we just need to remember s(x) but not x itself. + """ + + @staticmethod + def forward(ctx, x: Tensor) -> Tensor: + x = x.detach() + s = torch.sigmoid(x - 1.0) + y = x * s + ctx.save_for_backward(s, y) + return y + + @staticmethod + def backward(ctx, y_grad: Tensor) -> Tensor: + s, y = ctx.saved_tensors + return (y * (1 - s) + s) * y_grad + + +class DoubleSwish(torch.nn.Module): + def forward(self, x: Tensor) -> Tensor: + """Return double-swish activation function which is an approximation to Swish(Swish(x)), + that we approximate closely with x * sigmoid(x-1). + """ + if torch.jit.is_scripting() or is_jit_tracing(): + return x * torch.sigmoid(x - 1.0) + else: + return DoubleSwishFunction.apply(x) + + +class ScaledEmbedding(nn.Module): + r"""This is a modified version of nn.Embedding that introduces a learnable scale + on the parameters. Note: due to how we initialize it, it's best used with + schedulers like Noam that have a warmup period. + + It is a simple lookup table that stores embeddings of a fixed dictionary and size. + + This module is often used to store word embeddings and retrieve them using indices. + The input to the module is a list of indices, and the output is the corresponding + word embeddings. + + Args: + num_embeddings (int): size of the dictionary of embeddings + embedding_dim (int): the size of each embedding vector + padding_idx (int, optional): If given, pads the output with the embedding vector at :attr:`padding_idx` + (initialized to zeros) whenever it encounters the index. + scale_grad_by_freq (boolean, optional): If given, this will scale gradients by the inverse of frequency of + the words in the mini-batch. Default ``False``. + sparse (bool, optional): If ``True``, gradient w.r.t. :attr:`weight` matrix will be a sparse tensor. + See Notes for more details regarding sparse gradients. + + initial_speed (float, optional): This affects how fast the parameter will + learn near the start of training; you can set it to a value less than + one if you suspect that a module is contributing to instability near + the start of training. Note: regardless of the use of this option, + it's best to use schedulers like Noam that have a warm-up period. + Alternatively you can set it to more than 1 if you want it to + initially train faster. Must be greater than 0. + + + Attributes: + weight (Tensor): the learnable weights of the module of shape (num_embeddings, embedding_dim) + initialized from :math:`\mathcal{N}(0, 1)` + + Shape: + - Input: :math:`(*)`, LongTensor of arbitrary shape containing the indices to extract + - Output: :math:`(*, H)`, where `*` is the input shape and :math:`H=\text{embedding\_dim}` + + .. note:: + Keep in mind that only a limited number of optimizers support + sparse gradients: currently it's :class:`optim.SGD` (`CUDA` and `CPU`), + :class:`optim.SparseAdam` (`CUDA` and `CPU`) and :class:`optim.Adagrad` (`CPU`) + + .. note:: + With :attr:`padding_idx` set, the embedding vector at + :attr:`padding_idx` is initialized to all zeros. However, note that this + vector can be modified afterwards, e.g., using a customized + initialization method, and thus changing the vector used to pad the + output. The gradient for this vector from :class:`~torch.nn.Embedding` + is always zero. + + Examples:: + + >>> # an Embedding module containing 10 tensors of size 3 + >>> embedding = nn.Embedding(10, 3) + >>> # a batch of 2 samples of 4 indices each + >>> input = torch.LongTensor([[1,2,4,5],[4,3,2,9]]) + >>> embedding(input) + tensor([[[-0.0251, -1.6902, 0.7172], + [-0.6431, 0.0748, 0.6969], + [ 1.4970, 1.3448, -0.9685], + [-0.3677, -2.7265, -0.1685]], + + [[ 1.4970, 1.3448, -0.9685], + [ 0.4362, -0.4004, 0.9400], + [-0.6431, 0.0748, 0.6969], + [ 0.9124, -2.3616, 1.1151]]]) + + + >>> # example with padding_idx + >>> embedding = nn.Embedding(10, 3, padding_idx=0) + >>> input = torch.LongTensor([[0,2,0,5]]) + >>> embedding(input) + tensor([[[ 0.0000, 0.0000, 0.0000], + [ 0.1535, -2.0309, 0.9315], + [ 0.0000, 0.0000, 0.0000], + [-0.1655, 0.9897, 0.0635]]]) + + """ + __constants__ = [ + "num_embeddings", + "embedding_dim", + "padding_idx", + "scale_grad_by_freq", + "sparse", + ] + + num_embeddings: int + embedding_dim: int + padding_idx: int + scale_grad_by_freq: bool + weight: Tensor + sparse: bool + + def __init__( + self, + num_embeddings: int, + embedding_dim: int, + padding_idx: Optional[int] = None, + scale_grad_by_freq: bool = False, + sparse: bool = False, + initial_speed: float = 1.0, + ) -> None: + super(ScaledEmbedding, self).__init__() + self.num_embeddings = num_embeddings + self.embedding_dim = embedding_dim + if padding_idx is not None: + if padding_idx > 0: + assert ( + padding_idx < self.num_embeddings + ), "Padding_idx must be within num_embeddings" + elif padding_idx < 0: + assert ( + padding_idx >= -self.num_embeddings + ), "Padding_idx must be within num_embeddings" + padding_idx = self.num_embeddings + padding_idx + self.padding_idx = padding_idx + self.scale_grad_by_freq = scale_grad_by_freq + + self.scale = nn.Parameter(torch.zeros(())) # see reset_parameters() + self.sparse = sparse + + self.weight = nn.Parameter(torch.Tensor(num_embeddings, embedding_dim)) + self.reset_parameters(initial_speed) + + def reset_parameters(self, initial_speed: float = 1.0) -> None: + std = 0.1 / initial_speed + nn.init.normal_(self.weight, std=std) + nn.init.constant_(self.scale, torch.tensor(1.0 / std).log()) + + if self.padding_idx is not None: + with torch.no_grad(): + self.weight[self.padding_idx].fill_(0) + + def forward(self, input: Tensor) -> Tensor: + F = torch.nn.functional + scale = self.scale.exp() + if input.numel() < self.num_embeddings: + return ( + F.embedding( + input, + self.weight, + self.padding_idx, + None, + 2.0, # None, 2.0 relate to normalization + self.scale_grad_by_freq, + self.sparse, + ) + * scale + ) + else: + return F.embedding( + input, + self.weight * scale, + self.padding_idx, + None, + 2.0, # None, 2.0 relates to normalization + self.scale_grad_by_freq, + self.sparse, + ) + + def extra_repr(self) -> str: + # s = "{num_embeddings}, {embedding_dim}, scale={scale}" + s = "{num_embeddings}, {embedding_dim}" + if self.padding_idx is not None: + s += ", padding_idx={padding_idx}" + if self.scale_grad_by_freq is not False: + s += ", scale_grad_by_freq={scale_grad_by_freq}" + if self.sparse is not False: + s += ", sparse=True" + return s.format(**self.__dict__) + + +def _test_activation_balancer_sign(): + probs = torch.arange(0, 1, 0.01) + N = 1000 + x = 1.0 * (torch.rand(probs.numel(), N) < probs.unsqueeze(-1)) + x = x.detach() + x.requires_grad = True + m = ActivationBalancer( + channel_dim=0, + min_positive=0.05, + max_positive=0.95, + max_factor=0.2, + min_abs=0.0, + ) + + y_grad = torch.sign(torch.randn(probs.numel(), N)) + + y = m(x) + y.backward(gradient=y_grad) + print("_test_activation_balancer_sign: x = ", x) + print("_test_activation_balancer_sign: y grad = ", y_grad) + print("_test_activation_balancer_sign: x grad = ", x.grad) + + +def _test_activation_balancer_magnitude(): + magnitudes = torch.arange(0, 1, 0.01) + N = 1000 + x = torch.sign(torch.randn(magnitudes.numel(), N)) * magnitudes.unsqueeze(-1) + x = x.detach() + x.requires_grad = True + m = ActivationBalancer( + channel_dim=0, + min_positive=0.0, + max_positive=1.0, + max_factor=0.2, + min_abs=0.2, + max_abs=0.8, + ) + + y_grad = torch.sign(torch.randn(magnitudes.numel(), N)) + + y = m(x) + y.backward(gradient=y_grad) + print("_test_activation_balancer_magnitude: x = ", x) + print("_test_activation_balancer_magnitude: y grad = ", y_grad) + print("_test_activation_balancer_magnitude: x grad = ", x.grad) + + +def _test_basic_norm(): + num_channels = 128 + m = BasicNorm(num_channels=num_channels, channel_dim=1) + + x = torch.randn(500, num_channels) + + y = m(x) + + assert y.shape == x.shape + x_rms = (x**2).mean().sqrt() + y_rms = (y**2).mean().sqrt() + print("x rms = ", x_rms) + print("y rms = ", y_rms) + assert y_rms < x_rms + assert y_rms > 0.5 * x_rms + + +def _test_double_swish_deriv(): + x = torch.randn(10, 12, dtype=torch.double) * 0.5 + x.requires_grad = True + m = DoubleSwish() + torch.autograd.gradcheck(m, x) + + +def _test_scaled_lstm(): + N, L = 2, 30 + dim_in, dim_hidden = 10, 20 + m = ScaledLSTM(input_size=dim_in, hidden_size=dim_hidden, bias=True) + x = torch.randn(L, N, dim_in) + h0 = torch.randn(1, N, dim_hidden) + c0 = torch.randn(1, N, dim_hidden) + y, (h, c) = m(x, (h0, c0)) + assert y.shape == (L, N, dim_hidden) + assert h.shape == (1, N, dim_hidden) + assert c.shape == (1, N, dim_hidden) + + +def _test_grad_filter(): + threshold = 50.0 + time, batch, channel = 200, 5, 128 + grad_filter = GradientFilter(batch_dim=1, threshold=threshold) + + for i in range(2): + x = torch.randn(time, batch, channel, requires_grad=True) + w = nn.Parameter(torch.ones(5)) + b = nn.Parameter(torch.zeros(5)) + + x_out, w_out, b_out = grad_filter(x, w, b) + + w_out_grad = torch.randn_like(w) + b_out_grad = torch.randn_like(b) + x_out_grad = torch.rand_like(x) + if i % 2 == 1: + # The gradient norm of the first element must be larger than + # `threshold * median`, where `median` is the median value + # of gradient norms of all elements in batch. + x_out_grad[:, 0, :] = torch.full((time, channel), threshold) + + torch.autograd.backward( + [x_out, w_out, b_out], [x_out_grad, w_out_grad, b_out_grad] + ) + + print( + "_test_grad_filter: for gradient norms, the first element > median * threshold ", # noqa + i % 2 == 1, + ) + + print( + "_test_grad_filter: x_out_grad norm = ", + (x_out_grad**2).mean(dim=(0, 2)).sqrt(), + ) + print( + "_test_grad_filter: x.grad norm = ", + (x.grad**2).mean(dim=(0, 2)).sqrt(), + ) + print("_test_grad_filter: w_out_grad = ", w_out_grad) + print("_test_grad_filter: w.grad = ", w.grad) + print("_test_grad_filter: b_out_grad = ", b_out_grad) + print("_test_grad_filter: b.grad = ", b.grad) + + +if __name__ == "__main__": + _test_activation_balancer_sign() + _test_activation_balancer_magnitude() + _test_basic_norm() + _test_double_swish_deriv() + _test_scaled_lstm() + _test_grad_filter() diff --git a/egs/librispeech/ASR/incremental_transf/scaling_converter.py b/egs/librispeech/ASR/incremental_transf/scaling_converter.py new file mode 100644 index 000000000..a6540c584 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/scaling_converter.py @@ -0,0 +1,320 @@ +# Copyright 2022 Xiaomi Corp. (authors: Fangjun Kuang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +""" +This file provides functions to convert `ScaledLinear`, `ScaledConv1d`, +`ScaledConv2d`, and `ScaledEmbedding` to their non-scaled counterparts: +`nn.Linear`, `nn.Conv1d`, `nn.Conv2d`, and `nn.Embedding`. + +The scaled version are required only in the training time. It simplifies our +life by converting them to their non-scaled version during inference. +""" + +import copy +import re +from typing import List + +import torch +import torch.nn as nn +from lstmp import LSTMP +from scaling import ( + ActivationBalancer, + BasicNorm, + ScaledConv1d, + ScaledConv2d, + ScaledEmbedding, + ScaledLinear, + ScaledLSTM, +) + + +class NonScaledNorm(nn.Module): + """See BasicNorm for doc""" + + def __init__( + self, + num_channels: int, + eps_exp: float, + channel_dim: int = -1, # CAUTION: see documentation. + ): + super().__init__() + self.num_channels = num_channels + self.channel_dim = channel_dim + self.eps_exp = eps_exp + + def forward(self, x: torch.Tensor) -> torch.Tensor: + if not torch.jit.is_tracing(): + assert x.shape[self.channel_dim] == self.num_channels + scales = ( + torch.mean(x * x, dim=self.channel_dim, keepdim=True) + self.eps_exp + ).pow(-0.5) + return x * scales + + +def scaled_linear_to_linear(scaled_linear: ScaledLinear) -> nn.Linear: + """Convert an instance of ScaledLinear to nn.Linear. + + Args: + scaled_linear: + The layer to be converted. + Returns: + Return a linear layer. It satisfies: + + scaled_linear(x) == linear(x) + + for any given input tensor `x`. + """ + assert isinstance(scaled_linear, ScaledLinear), type(scaled_linear) + + weight = scaled_linear.get_weight() + bias = scaled_linear.get_bias() + has_bias = bias is not None + + linear = torch.nn.Linear( + in_features=scaled_linear.in_features, + out_features=scaled_linear.out_features, + bias=True, # otherwise, it throws errors when converting to PNNX format + # device=weight.device, # Pytorch version before v1.9.0 does not have + # this argument. Comment out for now, we will + # see if it will raise error for versions + # after v1.9.0 + ) + linear.weight.data.copy_(weight) + + if has_bias: + linear.bias.data.copy_(bias) + else: + linear.bias.data.zero_() + + return linear + + +def scaled_conv1d_to_conv1d(scaled_conv1d: ScaledConv1d) -> nn.Conv1d: + """Convert an instance of ScaledConv1d to nn.Conv1d. + + Args: + scaled_conv1d: + The layer to be converted. + Returns: + Return an instance of nn.Conv1d that has the same `forward()` behavior + of the given `scaled_conv1d`. + """ + assert isinstance(scaled_conv1d, ScaledConv1d), type(scaled_conv1d) + + weight = scaled_conv1d.get_weight() + bias = scaled_conv1d.get_bias() + has_bias = bias is not None + + conv1d = nn.Conv1d( + in_channels=scaled_conv1d.in_channels, + out_channels=scaled_conv1d.out_channels, + kernel_size=scaled_conv1d.kernel_size, + stride=scaled_conv1d.stride, + padding=scaled_conv1d.padding, + dilation=scaled_conv1d.dilation, + groups=scaled_conv1d.groups, + bias=scaled_conv1d.bias is not None, + padding_mode=scaled_conv1d.padding_mode, + ) + + conv1d.weight.data.copy_(weight) + if has_bias: + conv1d.bias.data.copy_(bias) + + return conv1d + + +def scaled_conv2d_to_conv2d(scaled_conv2d: ScaledConv2d) -> nn.Conv2d: + """Convert an instance of ScaledConv2d to nn.Conv2d. + + Args: + scaled_conv2d: + The layer to be converted. + Returns: + Return an instance of nn.Conv2d that has the same `forward()` behavior + of the given `scaled_conv2d`. + """ + assert isinstance(scaled_conv2d, ScaledConv2d), type(scaled_conv2d) + + weight = scaled_conv2d.get_weight() + bias = scaled_conv2d.get_bias() + has_bias = bias is not None + + conv2d = nn.Conv2d( + in_channels=scaled_conv2d.in_channels, + out_channels=scaled_conv2d.out_channels, + kernel_size=scaled_conv2d.kernel_size, + stride=scaled_conv2d.stride, + padding=scaled_conv2d.padding, + dilation=scaled_conv2d.dilation, + groups=scaled_conv2d.groups, + bias=scaled_conv2d.bias is not None, + padding_mode=scaled_conv2d.padding_mode, + ) + + conv2d.weight.data.copy_(weight) + if has_bias: + conv2d.bias.data.copy_(bias) + + return conv2d + + +def scaled_embedding_to_embedding( + scaled_embedding: ScaledEmbedding, +) -> nn.Embedding: + """Convert an instance of ScaledEmbedding to nn.Embedding. + + Args: + scaled_embedding: + The layer to be converted. + Returns: + Return an instance of nn.Embedding that has the same `forward()` behavior + of the given `scaled_embedding`. + """ + assert isinstance(scaled_embedding, ScaledEmbedding), type(scaled_embedding) + embedding = nn.Embedding( + num_embeddings=scaled_embedding.num_embeddings, + embedding_dim=scaled_embedding.embedding_dim, + padding_idx=scaled_embedding.padding_idx, + scale_grad_by_freq=scaled_embedding.scale_grad_by_freq, + sparse=scaled_embedding.sparse, + ) + weight = scaled_embedding.weight + scale = scaled_embedding.scale + + embedding.weight.data.copy_(weight * scale.exp()) + + return embedding + + +def convert_basic_norm(basic_norm: BasicNorm) -> NonScaledNorm: + assert isinstance(basic_norm, BasicNorm), type(BasicNorm) + norm = NonScaledNorm( + num_channels=basic_norm.num_channels, + eps_exp=basic_norm.eps.data.exp().item(), + channel_dim=basic_norm.channel_dim, + ) + return norm + + +def scaled_lstm_to_lstm(scaled_lstm: ScaledLSTM) -> nn.LSTM: + """Convert an instance of ScaledLSTM to nn.LSTM. + + Args: + scaled_lstm: + The layer to be converted. + Returns: + Return an instance of nn.LSTM that has the same `forward()` behavior + of the given `scaled_lstm`. + """ + assert isinstance(scaled_lstm, ScaledLSTM), type(scaled_lstm) + lstm = nn.LSTM( + input_size=scaled_lstm.input_size, + hidden_size=scaled_lstm.hidden_size, + num_layers=scaled_lstm.num_layers, + bias=scaled_lstm.bias, + batch_first=scaled_lstm.batch_first, + dropout=scaled_lstm.dropout, + bidirectional=scaled_lstm.bidirectional, + proj_size=scaled_lstm.proj_size, + ) + + assert lstm._flat_weights_names == scaled_lstm._flat_weights_names + for idx in range(len(scaled_lstm._flat_weights_names)): + scaled_weight = scaled_lstm._flat_weights[idx] * scaled_lstm._scales[idx].exp() + lstm._flat_weights[idx].data.copy_(scaled_weight) + + return lstm + + +# Copied from https://pytorch.org/docs/1.9.0/_modules/torch/nn/modules/module.html#Module.get_submodule # noqa +# get_submodule was added to nn.Module at v1.9.0 +def get_submodule(model, target): + if target == "": + return model + atoms: List[str] = target.split(".") + mod: torch.nn.Module = model + for item in atoms: + if not hasattr(mod, item): + raise AttributeError( + mod._get_name() + " has no " "attribute `" + item + "`" + ) + mod = getattr(mod, item) + if not isinstance(mod, torch.nn.Module): + raise AttributeError("`" + item + "` is not " "an nn.Module") + return mod + + +def convert_scaled_to_non_scaled( + model: nn.Module, + inplace: bool = False, + is_onnx: bool = False, +): + """Convert `ScaledLinear`, `ScaledConv1d`, and `ScaledConv2d` + in the given modle to their unscaled version `nn.Linear`, `nn.Conv1d`, + and `nn.Conv2d`. + + Args: + model: + The model to be converted. + inplace: + If True, the input model is modified inplace. + If False, the input model is copied and we modify the copied version. + is_onnx: + If True, we are going to export the model to ONNX. In this case, + we will convert nn.LSTM with proj_size to LSTMP. + Return: + Return a model without scaled layers. + """ + if not inplace: + model = copy.deepcopy(model) + + excluded_patterns = r"(self|src)_attn\.(in|out)_proj" + p = re.compile(excluded_patterns) + + d = {} + for name, m in model.named_modules(): + if isinstance(m, ScaledLinear): + if p.search(name) is not None: + continue + d[name] = scaled_linear_to_linear(m) + elif isinstance(m, ScaledConv1d): + d[name] = scaled_conv1d_to_conv1d(m) + elif isinstance(m, ScaledConv2d): + d[name] = scaled_conv2d_to_conv2d(m) + elif isinstance(m, ScaledEmbedding): + d[name] = scaled_embedding_to_embedding(m) + elif isinstance(m, BasicNorm): + d[name] = convert_basic_norm(m) + elif isinstance(m, ScaledLSTM): + if is_onnx: + d[name] = LSTMP(scaled_lstm_to_lstm(m)) + # See + # https://github.com/pytorch/pytorch/issues/47887 + # d[name] = torch.jit.script(LSTMP(scaled_lstm_to_lstm(m))) + else: + d[name] = scaled_lstm_to_lstm(m) + elif isinstance(m, ActivationBalancer): + d[name] = nn.Identity() + + for k, v in d.items(): + if "." in k: + parent, child = k.rsplit(".", maxsplit=1) + setattr(get_submodule(model, parent), child, v) + else: + setattr(model, k, v) + + return model diff --git a/egs/librispeech/ASR/incremental_transf/streaming_beam_search.py b/egs/librispeech/ASR/incremental_transf/streaming_beam_search.py new file mode 100644 index 000000000..e6e0fb1c8 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/streaming_beam_search.py @@ -0,0 +1,282 @@ +# Copyright 2022 Xiaomi Corp. (authors: Wei Kang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import warnings +from typing import List + +import k2 +import torch +import torch.nn as nn +from beam_search import Hypothesis, HypothesisList, get_hyps_shape +from decode_stream import DecodeStream + +from icefall.decode import one_best_decoding +from icefall.utils import get_texts + + +def greedy_search( + model: nn.Module, + encoder_out: torch.Tensor, + streams: List[DecodeStream], +) -> None: + """Greedy search in batch mode. It hardcodes --max-sym-per-frame=1. + + Args: + model: + The transducer model. + encoder_out: + Output from the encoder. Its shape is (N, T, C), where N >= 1. + streams: + A list of Stream objects. + """ + assert len(streams) == encoder_out.size(0) + assert encoder_out.ndim == 3 + + blank_id = model.decoder.blank_id + context_size = model.decoder.context_size + device = model.device + T = encoder_out.size(1) + + decoder_input = torch.tensor( + [stream.hyp[-context_size:] for stream in streams], + device=device, + dtype=torch.int64, + ) + # decoder_out is of shape (N, 1, decoder_out_dim) + decoder_out = model.decoder(decoder_input, need_pad=False) + decoder_out = model.joiner.decoder_proj(decoder_out) + + for t in range(T): + # current_encoder_out's shape: (batch_size, 1, encoder_out_dim) + current_encoder_out = encoder_out[:, t : t + 1, :] # noqa + + logits = model.joiner( + current_encoder_out.unsqueeze(2), + decoder_out.unsqueeze(1), + project_input=False, + ) + # logits'shape (batch_size, vocab_size) + logits = logits.squeeze(1).squeeze(1) + + assert logits.ndim == 2, logits.shape + y = logits.argmax(dim=1).tolist() + emitted = False + for i, v in enumerate(y): + if v != blank_id: + streams[i].hyp.append(v) + emitted = True + if emitted: + # update decoder output + decoder_input = torch.tensor( + [stream.hyp[-context_size:] for stream in streams], + device=device, + dtype=torch.int64, + ) + decoder_out = model.decoder( + decoder_input, + need_pad=False, + ) + decoder_out = model.joiner.decoder_proj(decoder_out) + + +def modified_beam_search( + model: nn.Module, + encoder_out: torch.Tensor, + streams: List[DecodeStream], + num_active_paths: int = 4, +) -> None: + """Beam search in batch mode with --max-sym-per-frame=1 being hardcoded. + + Args: + model: + The RNN-T model. + encoder_out: + A 3-D tensor of shape (N, T, encoder_out_dim) containing the output of + the encoder model. + streams: + A list of stream objects. + num_active_paths: + Number of active paths during the beam search. + """ + assert encoder_out.ndim == 3, encoder_out.shape + assert len(streams) == encoder_out.size(0) + + blank_id = model.decoder.blank_id + context_size = model.decoder.context_size + device = next(model.parameters()).device + batch_size = len(streams) + T = encoder_out.size(1) + + B = [stream.hyps for stream in streams] + + for t in range(T): + current_encoder_out = encoder_out[:, t].unsqueeze(1).unsqueeze(1) + # current_encoder_out's shape: (batch_size, 1, 1, encoder_out_dim) + + hyps_shape = get_hyps_shape(B).to(device) + + A = [list(b) for b in B] + B = [HypothesisList() for _ in range(batch_size)] + + ys_log_probs = torch.stack( + [hyp.log_prob.reshape(1) for hyps in A for hyp in hyps], dim=0 + ) # (num_hyps, 1) + + decoder_input = torch.tensor( + [hyp.ys[-context_size:] for hyps in A for hyp in hyps], + device=device, + dtype=torch.int64, + ) # (num_hyps, context_size) + + decoder_out = model.decoder(decoder_input, need_pad=False).unsqueeze(1) + decoder_out = model.joiner.decoder_proj(decoder_out) + # decoder_out is of shape (num_hyps, 1, 1, decoder_output_dim) + + # Note: For torch 1.7.1 and below, it requires a torch.int64 tensor + # as index, so we use `to(torch.int64)` below. + current_encoder_out = torch.index_select( + current_encoder_out, + dim=0, + index=hyps_shape.row_ids(1).to(torch.int64), + ) # (num_hyps, encoder_out_dim) + + logits = model.joiner(current_encoder_out, decoder_out, project_input=False) + # logits is of shape (num_hyps, 1, 1, vocab_size) + + logits = logits.squeeze(1).squeeze(1) + + log_probs = logits.log_softmax(dim=-1) # (num_hyps, vocab_size) + + log_probs.add_(ys_log_probs) + + vocab_size = log_probs.size(-1) + + log_probs = log_probs.reshape(-1) + + row_splits = hyps_shape.row_splits(1) * vocab_size + log_probs_shape = k2.ragged.create_ragged_shape2( + row_splits=row_splits, cached_tot_size=log_probs.numel() + ) + ragged_log_probs = k2.RaggedTensor(shape=log_probs_shape, value=log_probs) + + for i in range(batch_size): + topk_log_probs, topk_indexes = ragged_log_probs[i].topk(num_active_paths) + + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + topk_hyp_indexes = (topk_indexes // vocab_size).tolist() + topk_token_indexes = (topk_indexes % vocab_size).tolist() + + for k in range(len(topk_hyp_indexes)): + hyp_idx = topk_hyp_indexes[k] + hyp = A[i][hyp_idx] + + new_ys = hyp.ys[:] + new_token = topk_token_indexes[k] + if new_token != blank_id: + new_ys.append(new_token) + + new_log_prob = topk_log_probs[k] + new_hyp = Hypothesis(ys=new_ys, log_prob=new_log_prob) + B[i].add(new_hyp) + + for i in range(batch_size): + streams[i].hyps = B[i] + + +def fast_beam_search_one_best( + model: nn.Module, + encoder_out: torch.Tensor, + processed_lens: torch.Tensor, + streams: List[DecodeStream], + beam: float, + max_states: int, + max_contexts: int, +) -> None: + """It limits the maximum number of symbols per frame to 1. + + A lattice is first generated by Fsa-based beam search, then we get the + recognition by applying shortest path on the lattice. + + Args: + model: + An instance of `Transducer`. + encoder_out: + A tensor of shape (N, T, C) from the encoder. + processed_lens: + A tensor of shape (N,) containing the number of processed frames + in `encoder_out` before padding. + streams: + A list of stream objects. + 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. + """ + assert encoder_out.ndim == 3 + B, T, C = encoder_out.shape + assert B == len(streams) + + context_size = model.decoder.context_size + vocab_size = model.decoder.vocab_size + + config = k2.RnntDecodingConfig( + vocab_size=vocab_size, + decoder_history_len=context_size, + beam=beam, + max_contexts=max_contexts, + max_states=max_states, + ) + individual_streams = [] + for i in range(B): + individual_streams.append(streams[i].rnnt_decoding_stream) + decoding_streams = k2.RnntDecodingStreams(individual_streams, config) + + for t in range(T): + # shape is a RaggedShape of shape (B, context) + # contexts is a Tensor of shape (shape.NumElements(), context_size) + shape, contexts = decoding_streams.get_contexts() + # `nn.Embedding()` in torch below v1.7.1 supports only torch.int64 + contexts = contexts.to(torch.int64) + # decoder_out is of shape (shape.NumElements(), 1, decoder_out_dim) + decoder_out = model.decoder(contexts, need_pad=False) + decoder_out = model.joiner.decoder_proj(decoder_out) + # current_encoder_out is of shape + # (shape.NumElements(), 1, joiner_dim) + # fmt: off + current_encoder_out = torch.index_select( + encoder_out[:, t:t + 1, :], 0, shape.row_ids(1).to(torch.int64) + ) + # fmt: on + logits = model.joiner( + current_encoder_out.unsqueeze(2), + decoder_out.unsqueeze(1), + project_input=False, + ) + logits = logits.squeeze(1).squeeze(1) + log_probs = logits.log_softmax(dim=-1) + decoding_streams.advance(log_probs) + + decoding_streams.terminate_and_flush_to_streams() + + lattice = decoding_streams.format_output(processed_lens.tolist()) + best_path = one_best_decoding(lattice) + hyp_tokens = get_texts(best_path) + + for i in range(B): + streams[i].hyp = hyp_tokens[i] diff --git a/egs/librispeech/ASR/incremental_transf/streaming_decode.py b/egs/librispeech/ASR/incremental_transf/streaming_decode.py new file mode 100755 index 000000000..064811f1c --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/streaming_decode.py @@ -0,0 +1,653 @@ +#!/usr/bin/env python3 +# Copyright 2022 Xiaomi Corporation (Authors: Wei Kang, Fangjun Kuang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +""" +Usage: +./pruned_transducer_stateless5/streaming_decode.py \ + --epoch 28 \ + --avg 15 \ + --left-context 32 \ + --decode-chunk-size 8 \ + --right-context 0 \ + --exp-dir ./pruned_transducer_stateless5/exp \ + --decoding_method greedy_search \ + --num-decode-streams 200 +""" + +import argparse +import logging +import math +from pathlib import Path +from typing import Dict, List, Optional, Tuple + +import k2 +import numpy as np +import sentencepiece as spm +import torch +import torch.nn as nn +from asr_datamodule import LibriSpeechAsrDataModule +from decode_stream import DecodeStream +from kaldifeat import Fbank, FbankOptions +from lhotse import CutSet +from streaming_beam_search import ( + fast_beam_search_one_best, + greedy_search, + modified_beam_search, +) +from torch.nn.utils.rnn import pad_sequence +from train import add_model_arguments, get_params, get_transducer_model + +from icefall.checkpoint import ( + average_checkpoints, + average_checkpoints_with_averaged_model, + find_checkpoints, + load_checkpoint, +) +from icefall.utils import ( + AttributeDict, + setup_logger, + store_transcripts, + str2bool, + write_error_stats, +) + +LOG_EPS = math.log(1e-10) + + +def get_parser(): + parser = argparse.ArgumentParser( + formatter_class=argparse.ArgumentDefaultsHelpFormatter + ) + + parser.add_argument( + "--epoch", + type=int, + default=28, + help="""It specifies the checkpoint to use for decoding. + Note: Epoch counts from 0. + You can specify --avg to use more checkpoints for model averaging.""", + ) + + parser.add_argument( + "--iter", + type=int, + default=0, + help="""If positive, --epoch is ignored and it + will use the checkpoint exp_dir/checkpoint-iter.pt. + You can specify --avg to use more checkpoints for model averaging. + """, + ) + + parser.add_argument( + "--avg", + type=int, + default=15, + help="Number of checkpoints to average. Automatically select " + "consecutive checkpoints before the checkpoint specified by " + "'--epoch' and '--iter'", + ) + + parser.add_argument( + "--use-averaged-model", + type=str2bool, + 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`." + "Actually only the models with epoch number of `epoch-avg` and " + "`epoch` are loaded for averaging. ", + ) + + parser.add_argument( + "--exp-dir", + type=str, + default="pruned_transducer_stateless2/exp", + help="The experiment dir", + ) + + parser.add_argument( + "--bpe-model", + type=str, + default="data/lang_bpe_500/bpe.model", + help="Path to the BPE model", + ) + + parser.add_argument( + "--decoding-method", + type=str, + default="greedy_search", + help="""Supported decoding methods are: + greedy_search + modified_beam_search + fast_beam_search + """, + ) + + parser.add_argument( + "--num_active_paths", + type=int, + default=4, + help="""An interger indicating how many candidates we will keep for each + frame. Used only when --decoding-method is modified_beam_search.""", + ) + + parser.add_argument( + "--beam", + type=float, + default=4, + 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( + "--max-contexts", + type=int, + default=4, + help="""Used only when --decoding-method is + fast_beam_search""", + ) + + parser.add_argument( + "--max-states", + type=int, + default=32, + help="""Used only when --decoding-method is + fast_beam_search""", + ) + + parser.add_argument( + "--context-size", + type=int, + default=2, + help="The context size in the decoder. 1 means bigram; 2 means tri-gram", + ) + + parser.add_argument( + "--decode-chunk-size", + type=int, + default=16, + help="The chunk size for decoding (in frames after subsampling)", + ) + + parser.add_argument( + "--left-context", + type=int, + default=64, + help="left context can be seen during decoding (in frames after subsampling)", + ) + + parser.add_argument( + "--right-context", + type=int, + default=0, + help="right context can be seen during decoding (in frames after subsampling)", + ) + + parser.add_argument( + "--num-decode-streams", + type=int, + default=2000, + help="The number of streams that can be decoded parallel.", + ) + + add_model_arguments(parser) + + return parser + + +def decode_one_chunk( + params: AttributeDict, + model: nn.Module, + decode_streams: List[DecodeStream], +) -> List[int]: + """Decode one chunk frames of features for each decode_streams and + return the indexes of finished streams in a List. + + Args: + params: + It's the return value of :func:`get_params`. + model: + The neural model. + decode_streams: + A List of DecodeStream, each belonging to a utterance. + Returns: + Return a List containing which DecodeStreams are finished. + """ + device = model.device + + features = [] + feature_lens = [] + states = [] + + processed_lens = [] + + for stream in decode_streams: + feat, feat_len = stream.get_feature_frames( + params.decode_chunk_size * params.subsampling_factor + ) + features.append(feat) + feature_lens.append(feat_len) + states.append(stream.states) + processed_lens.append(stream.done_frames) + + feature_lens = torch.tensor(feature_lens, device=device) + features = pad_sequence(features, batch_first=True, padding_value=LOG_EPS) + + # if T is less than 7 there will be an error in time reduction layer, + # because we subsample features with ((x_len - 1) // 2 - 1) // 2 + # we plus 2 here because we will cut off one frame on each size of + # encoder_embed output as they see invalid paddings. so we need extra 2 + # frames. + tail_length = 7 + (2 + params.right_context) * params.subsampling_factor + if features.size(1) < tail_length: + pad_length = tail_length - features.size(1) + feature_lens += pad_length + features = torch.nn.functional.pad( + features, + (0, 0, 0, pad_length), + mode="constant", + value=LOG_EPS, + ) + + states = [ + torch.stack([x[0] for x in states], dim=2), + torch.stack([x[1] for x in states], dim=2), + ] + processed_lens = torch.tensor(processed_lens, device=device) + + encoder_out, encoder_out_lens, states = model.encoder.streaming_forward( + x=features, + x_lens=feature_lens, + states=states, + left_context=params.left_context, + right_context=params.right_context, + processed_lens=processed_lens, + ) + + encoder_out = model.joiner.encoder_proj(encoder_out) + + if params.decoding_method == "greedy_search": + greedy_search(model=model, encoder_out=encoder_out, streams=decode_streams) + elif params.decoding_method == "fast_beam_search": + processed_lens = processed_lens + encoder_out_lens + fast_beam_search_one_best( + model=model, + encoder_out=encoder_out, + processed_lens=processed_lens, + streams=decode_streams, + beam=params.beam, + max_states=params.max_states, + max_contexts=params.max_contexts, + ) + elif params.decoding_method == "modified_beam_search": + modified_beam_search( + model=model, + streams=decode_streams, + encoder_out=encoder_out, + num_active_paths=params.num_active_paths, + ) + else: + raise ValueError(f"Unsupported decoding method: {params.decoding_method}") + + states = [torch.unbind(states[0], dim=2), torch.unbind(states[1], dim=2)] + + finished_streams = [] + for i in range(len(decode_streams)): + decode_streams[i].states = [states[0][i], states[1][i]] + decode_streams[i].done_frames += encoder_out_lens[i] + if decode_streams[i].done: + finished_streams.append(i) + + return finished_streams + + +def decode_dataset( + cuts: CutSet, + params: AttributeDict, + model: nn.Module, + sp: spm.SentencePieceProcessor, + decoding_graph: Optional[k2.Fsa] = None, +) -> Dict[str, List[Tuple[List[str], List[str]]]]: + """Decode dataset. + + Args: + cuts: + Lhotse Cutset containing the dataset to decode. + params: + It is returned by :func:`get_params`. + model: + The neural model. + sp: + The BPE model. + decoding_graph: + The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used + only when --decoding_method is fast_beam_search. + 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. + Its value is a list of tuples. Each tuple contains two elements: + The first is the reference transcript, and the second is the + predicted result. + """ + device = model.device + + opts = FbankOptions() + opts.device = device + opts.frame_opts.dither = 0 + opts.frame_opts.snip_edges = False + opts.frame_opts.samp_freq = 16000 + opts.mel_opts.num_bins = 80 + + log_interval = 50 + + decode_results = [] + # Contain decode streams currently running. + decode_streams = [] + initial_states = model.encoder.get_init_state(params.left_context, device=device) + for num, cut in enumerate(cuts): + # each utterance has a DecodeStream. + decode_stream = DecodeStream( + params=params, + cut_id=cut.id, + initial_states=initial_states, + decoding_graph=decoding_graph, + device=device, + ) + + audio: np.ndarray = cut.load_audio() + # audio.shape: (1, num_samples) + assert len(audio.shape) == 2 + assert audio.shape[0] == 1, "Should be single channel" + assert audio.dtype == np.float32, audio.dtype + + # The trained model is using normalized samples + assert audio.max() <= 1, "Should be normalized to [-1, 1])" + + samples = torch.from_numpy(audio).squeeze(0) + + fbank = Fbank(opts) + feature = fbank(samples.to(device)) + decode_stream.set_features(feature) + decode_stream.ground_truth = cut.supervisions[0].text + + decode_streams.append(decode_stream) + + while len(decode_streams) >= params.num_decode_streams: + finished_streams = decode_one_chunk( + params=params, model=model, decode_streams=decode_streams + ) + for i in sorted(finished_streams, reverse=True): + decode_results.append( + ( + decode_streams[i].id, + decode_streams[i].ground_truth.split(), + sp.decode(decode_streams[i].decoding_result()).split(), + ) + ) + del decode_streams[i] + + if num % log_interval == 0: + logging.info(f"Cuts processed until now is {num}.") + + # decode final chunks of last sequences + while len(decode_streams): + finished_streams = decode_one_chunk( + params=params, model=model, decode_streams=decode_streams + ) + for i in sorted(finished_streams, reverse=True): + decode_results.append( + ( + decode_streams[i].id, + decode_streams[i].ground_truth.split(), + sp.decode(decode_streams[i].decoding_result()).split(), + ) + ) + del decode_streams[i] + + if params.decoding_method == "greedy_search": + key = "greedy_search" + elif params.decoding_method == "fast_beam_search": + key = ( + f"beam_{params.beam}_" + f"max_contexts_{params.max_contexts}_" + f"max_states_{params.max_states}" + ) + elif params.decoding_method == "modified_beam_search": + key = f"num_active_paths_{params.num_active_paths}" + else: + raise ValueError(f"Unsupported decoding method: {params.decoding_method}") + return {key: decode_results} + + +def save_results( + params: AttributeDict, + test_set_name: str, + results_dict: Dict[str, List[Tuple[List[str], List[str]]]], +): + test_set_wers = dict() + for key, results in results_dict.items(): + recog_path = ( + params.res_dir / f"recogs-{test_set_name}-{key}-{params.suffix}.txt" + ) + results = sorted(results) + store_transcripts(filename=recog_path, texts=results) + logging.info(f"The transcripts are stored in {recog_path}") + + # The following prints out WERs, per-word error statistics and aligned + # ref/hyp pairs. + errs_filename = ( + params.res_dir / f"errs-{test_set_name}-{key}-{params.suffix}.txt" + ) + with open(errs_filename, "w") as f: + wer = write_error_stats( + f, f"{test_set_name}-{key}", results, enable_log=True + ) + test_set_wers[key] = wer + + logging.info("Wrote detailed error stats to {}".format(errs_filename)) + + test_set_wers = sorted(test_set_wers.items(), key=lambda x: x[1]) + errs_info = ( + params.res_dir / f"wer-summary-{test_set_name}-{key}-{params.suffix}.txt" + ) + with open(errs_info, "w") as f: + print("settings\tWER", file=f) + for key, val in test_set_wers: + print("{}\t{}".format(key, val), file=f) + + s = "\nFor {}, WER of different settings are:\n".format(test_set_name) + note = "\tbest for {}".format(test_set_name) + for key, val in test_set_wers: + s += "{}\t{}{}\n".format(key, val, note) + note = "" + logging.info(s) + + +@torch.no_grad() +def main(): + parser = get_parser() + LibriSpeechAsrDataModule.add_arguments(parser) + args = parser.parse_args() + args.exp_dir = Path(args.exp_dir) + + params = get_params() + params.update(vars(args)) + + params.res_dir = params.exp_dir / "streaming" / params.decoding_method + + if params.iter > 0: + params.suffix = f"iter-{params.iter}-avg-{params.avg}" + else: + params.suffix = f"epoch-{params.epoch}-avg-{params.avg}" + + # for streaming + params.suffix += f"-streaming-chunk-size-{params.decode_chunk_size}" + params.suffix += f"-left-context-{params.left_context}" + params.suffix += f"-right-context-{params.right_context}" + + # for fast_beam_search + if params.decoding_method == "fast_beam_search": + params.suffix += f"-beam-{params.beam}" + params.suffix += f"-max-contexts-{params.max_contexts}" + params.suffix += f"-max-states-{params.max_states}" + + if params.use_averaged_model: + params.suffix += "-use-averaged-model" + + setup_logger(f"{params.res_dir}/log-decode-{params.suffix}") + logging.info("Decoding started") + + device = torch.device("cpu") + if torch.cuda.is_available(): + device = torch.device("cuda", 0) + + logging.info(f"Device: {device}") + + sp = spm.SentencePieceProcessor() + sp.load(params.bpe_model) + + # and is defined in local/train_bpe_model.py + params.blank_id = sp.piece_to_id("") + params.unk_id = sp.piece_to_id("") + params.vocab_size = sp.get_piece_size() + + # Decoding in streaming requires causal convolution + params.causal_convolution = True + + logging.info(params) + + logging.info("About to create model") + model = get_transducer_model(params) + + if not params.use_averaged_model: + if params.iter > 0: + filenames = find_checkpoints(params.exp_dir, iteration=-params.iter)[ + : params.avg + ] + if len(filenames) == 0: + raise ValueError( + f"No checkpoints found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + elif len(filenames) < params.avg: + raise ValueError( + f"Not enough checkpoints ({len(filenames)}) found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + logging.info(f"averaging {filenames}") + model.to(device) + model.load_state_dict(average_checkpoints(filenames, device=device)) + elif params.avg == 1: + load_checkpoint(f"{params.exp_dir}/epoch-{params.epoch}.pt", model) + else: + start = params.epoch - params.avg + 1 + filenames = [] + for i in range(start, params.epoch + 1): + if start >= 0: + filenames.append(f"{params.exp_dir}/epoch-{i}.pt") + logging.info(f"averaging {filenames}") + model.to(device) + model.load_state_dict(average_checkpoints(filenames, device=device)) + else: + if params.iter > 0: + filenames = find_checkpoints(params.exp_dir, iteration=-params.iter)[ + : params.avg + 1 + ] + if len(filenames) == 0: + raise ValueError( + f"No checkpoints found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + elif len(filenames) < params.avg + 1: + raise ValueError( + f"Not enough checkpoints ({len(filenames)}) found for" + f" --iter {params.iter}, --avg {params.avg}" + ) + filename_start = filenames[-1] + filename_end = filenames[0] + logging.info( + "Calculating the averaged model over iteration checkpoints" + f" from {filename_start} (excluded) to {filename_end}" + ) + model.to(device) + model.load_state_dict( + average_checkpoints_with_averaged_model( + filename_start=filename_start, + filename_end=filename_end, + device=device, + ) + ) + else: + assert params.avg > 0, params.avg + start = params.epoch - params.avg + assert start >= 1, start + filename_start = f"{params.exp_dir}/epoch-{start}.pt" + filename_end = f"{params.exp_dir}/epoch-{params.epoch}.pt" + logging.info( + f"Calculating the averaged model over epoch range from " + f"{start} (excluded) to {params.epoch}" + ) + model.to(device) + model.load_state_dict( + average_checkpoints_with_averaged_model( + filename_start=filename_start, + filename_end=filename_end, + device=device, + ) + ) + + model.to(device) + model.eval() + model.device = device + + decoding_graph = None + if params.decoding_method == "fast_beam_search": + decoding_graph = k2.trivial_graph(params.vocab_size - 1, device=device) + + num_param = sum([p.numel() for p in model.parameters()]) + logging.info(f"Number of model parameters: {num_param}") + + librispeech = LibriSpeechAsrDataModule(args) + + test_clean_cuts = librispeech.test_clean_cuts() + test_other_cuts = librispeech.test_other_cuts() + + test_sets = ["test-clean", "test-other"] + test_cuts = [test_clean_cuts, test_other_cuts] + + for test_set, test_cut in zip(test_sets, test_cuts): + results_dict = decode_dataset( + cuts=test_cut, + params=params, + model=model, + sp=sp, + decoding_graph=decoding_graph, + ) + + save_results( + params=params, + test_set_name=test_set, + results_dict=results_dict, + ) + + logging.info("Done!") + + +if __name__ == "__main__": + main() diff --git a/egs/librispeech/ASR/incremental_transf/test_model.py b/egs/librispeech/ASR/incremental_transf/test_model.py new file mode 100755 index 000000000..9aad32014 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/test_model.py @@ -0,0 +1,65 @@ +#!/usr/bin/env python3 +# Copyright 2022 Xiaomi Corp. (authors: Fangjun Kuang) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + + +""" +To run this file, do: + + cd icefall/egs/librispeech/ASR + python ./pruned_transducer_stateless4/test_model.py +""" + +from train import get_params, get_transducer_model + + +def test_model_1(): + params = get_params() + params.vocab_size = 500 + params.blank_id = 0 + params.context_size = 2 + params.num_encoder_layers = 24 + params.dim_feedforward = 1536 # 384 * 4 + params.encoder_dim = 384 + model = get_transducer_model(params) + num_param = sum([p.numel() for p in model.parameters()]) + print(f"Number of model parameters: {num_param}") + + +# See Table 1 from https://arxiv.org/pdf/2005.08100.pdf +def test_model_M(): + params = get_params() + params.vocab_size = 500 + params.blank_id = 0 + params.context_size = 2 + params.num_encoder_layers = 18 + params.dim_feedforward = 1024 + params.encoder_dim = 256 + params.nhead = 4 + params.decoder_dim = 512 + params.joiner_dim = 512 + model = get_transducer_model(params) + num_param = sum([p.numel() for p in model.parameters()]) + print(f"Number of model parameters: {num_param}") + + +def main(): + # test_model_1() + test_model_M() + + +if __name__ == "__main__": + main() diff --git a/egs/librispeech/ASR/incremental_transf/train.py b/egs/librispeech/ASR/incremental_transf/train.py new file mode 100755 index 000000000..567ceafa7 --- /dev/null +++ b/egs/librispeech/ASR/incremental_transf/train.py @@ -0,0 +1,1195 @@ +#!/usr/bin/env python3 +# Copyright 2021-2022 Xiaomi Corp. (authors: Fangjun Kuang, +# Wei Kang, +# Mingshuang Luo,) +# Zengwei Yao) +# +# See ../../../../LICENSE for clarification regarding multiple authors +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +""" +Usage: + +export CUDA_VISIBLE_DEVICES="0,1,2,3" + +./pruned_transducer_stateless5/train.py \ + --world-size 4 \ + --num-epochs 30 \ + --start-epoch 1 \ + --exp-dir pruned_transducer_stateless5/exp \ + --full-libri 1 \ + --max-duration 300 + +# For mix precision training: + +./pruned_transducer_stateless5/train.py \ + --world-size 4 \ + --num-epochs 30 \ + --start-epoch 1 \ + --use-fp16 1 \ + --exp-dir pruned_transducer_stateless5/exp \ + --full-libri 1 \ + --max-duration 550 + +""" + + +import argparse +import copy +import logging +import warnings +from pathlib import Path +from shutil import copyfile +from typing import Any, Dict, Optional, Tuple, Union + +import k2 +import optim +import sentencepiece as spm +import torch +import torch.multiprocessing as mp +import torch.nn as nn +from asr_datamodule import LibriSpeechAsrDataModule +from conformer import Conformer +from decoder import Decoder +from joiner import Joiner +from lhotse.cut import Cut +from lhotse.dataset.sampling.base import CutSampler +from lhotse.utils import fix_random_seed +from model import Transducer +from optim import Eden, Eve +from torch import Tensor +from torch.cuda.amp import GradScaler +from torch.nn.parallel import DistributedDataParallel as DDP +from torch.utils.tensorboard import SummaryWriter + +from icefall import diagnostics +from icefall.checkpoint import load_checkpoint, remove_checkpoints +from icefall.checkpoint import save_checkpoint as save_checkpoint_impl +from icefall.checkpoint import ( + save_checkpoint_with_global_batch_idx, + update_averaged_model, +) +from icefall.dist import cleanup_dist, setup_dist +from icefall.env import get_env_info +from icefall.utils import ( + AttributeDict, + MetricsTracker, + display_and_save_batch, + setup_logger, + str2bool, +) + +LRSchedulerType = Union[torch.optim.lr_scheduler._LRScheduler, optim.LRScheduler] + + +def add_model_arguments(parser: argparse.ArgumentParser): + parser.add_argument( + "--num-encoder-layers", + type=int, + default=24, + help="Number of conformer encoder layers..", + ) + + parser.add_argument( + "--dim-feedforward", + type=int, + default=1536, + help="Feedforward dimension of the conformer encoder layer.", + ) + + parser.add_argument( + "--nhead", + type=int, + default=8, + help="Number of attention heads in the conformer encoder layer.", + ) + + parser.add_argument( + "--encoder-dim", + type=int, + default=384, + help="Attention dimension in the conformer encoder layer.", + ) + + parser.add_argument( + "--decoder-dim", + type=int, + default=512, + help="Embedding dimension in the decoder model.", + ) + + parser.add_argument( + "--joiner-dim", + type=int, + default=512, + help="""Dimension used in the joiner model. + Outputs from the encoder and decoder model are projected + to this dimension before adding. + """, + ) + + parser.add_argument( + "--dynamic-chunk-training", + type=str2bool, + default=False, + help="""Whether to use dynamic_chunk_training, if you want a streaming + model, this requires to be True. + """, + ) + + parser.add_argument( + "--causal-convolution", + type=str2bool, + default=False, + help="""Whether to use causal convolution, this requires to be True when + using dynamic_chunk_training. + """, + ) + + parser.add_argument( + "--short-chunk-size", + type=int, + default=25, + help="""Chunk length of dynamic training, the chunk size would be either + max sequence length of current batch or uniformly sampled from (1, short_chunk_size). + """, + ) + + parser.add_argument( + "--num-left-chunks", + type=int, + default=4, + help="How many left context can be seen in chunks when calculating attention.", + ) + + +def get_parser(): + parser = argparse.ArgumentParser( + formatter_class=argparse.ArgumentDefaultsHelpFormatter + ) + + parser.add_argument( + "--world-size", + type=int, + default=1, + help="Number of GPUs for DDP training.", + ) + + parser.add_argument( + "--master-port", + type=int, + default=12354, + help="Master port to use for DDP training.", + ) + + parser.add_argument( + "--tensorboard", + type=str2bool, + default=True, + help="Should various information be logged in tensorboard.", + ) + + parser.add_argument( + "--num-epochs", + type=int, + default=30, + help="Number of epochs to train.", + ) + + parser.add_argument( + "--start-epoch", + type=int, + default=1, + help="""Resume training from this epoch. It should be positive. + If larger than 1, it will load checkpoint from + exp-dir/epoch-{start_epoch-1}.pt + """, + ) + + parser.add_argument( + "--start-batch", + type=int, + default=0, + help="""If positive, --start-epoch is ignored and + it loads the checkpoint from exp-dir/checkpoint-{start_batch}.pt + """, + ) + + parser.add_argument( + "--exp-dir", + type=str, + default="pruned_transducer_stateless5/exp", + help="""The experiment dir. + It specifies the directory where all training related + files, e.g., checkpoints, log, etc, are saved + """, + ) + + parser.add_argument( + "--bpe-model", + type=str, + default="data/lang_bpe_500/bpe.model", + help="Path to the BPE model", + ) + + parser.add_argument( + "--initial-lr", + type=float, + default=0.003, + help="The initial learning rate. This value should not need to be changed.", + ) + + parser.add_argument( + "--lr-batches", + type=float, + default=5000, + help="""Number of steps that affects how rapidly the learning rate + decreases. We suggest not to change this.""", + ) + + parser.add_argument( + "--lr-epochs", + type=float, + default=6, + help="""Number of epochs that affects how rapidly the learning rate decreases. + """, + ) + + parser.add_argument( + "--context-size", + type=int, + default=2, + help="The context size in the decoder. 1 means bigram; 2 means tri-gram", + ) + + parser.add_argument( + "--prune-range", + type=int, + default=5, + help="The prune range for rnnt loss, it means how many symbols(context)" + "we are using to compute the loss", + ) + + parser.add_argument( + "--lm-scale", + type=float, + default=0.25, + help="The scale to smooth the loss with lm " + "(output of prediction network) part.", + ) + + parser.add_argument( + "--am-scale", + type=float, + default=0.0, + help="The scale to smooth the loss with am (output of encoder network) part.", + ) + + parser.add_argument( + "--simple-loss-scale", + type=float, + default=0.5, + help="To get pruning ranges, we will calculate a simple version" + "loss(joiner is just addition), this simple loss also uses for" + "training (as a regularization item). We will scale the simple loss" + "with this parameter before adding to the final loss.", + ) + + parser.add_argument( + "--seed", + type=int, + default=42, + help="The seed for random generators intended for reproducibility", + ) + + parser.add_argument( + "--print-diagnostics", + type=str2bool, + default=False, + help="Accumulate stats on activations, print them and exit.", + ) + + parser.add_argument( + "--save-every-n", + type=int, + default=4000, + help="""Save checkpoint after processing this number of batches" + periodically. We save checkpoint to exp-dir/ whenever + params.batch_idx_train % save_every_n == 0. The checkpoint filename + has the form: f'exp-dir/checkpoint-{params.batch_idx_train}.pt' + Note: It also saves checkpoint to `exp-dir/epoch-xxx.pt` at the + end of each epoch where `xxx` is the epoch number counting from 0. + """, + ) + + parser.add_argument( + "--keep-last-k", + type=int, + default=30, + help="""Only keep this number of checkpoints on disk. + For instance, if it is 3, there are only 3 checkpoints + in the exp-dir with filenames `checkpoint-xxx.pt`. + It does not affect checkpoints with name `epoch-xxx.pt`. + """, + ) + + parser.add_argument( + "--average-period", + type=int, + default=100, + help="""Update the averaged model, namely `model_avg`, after processing + this number of batches. `model_avg` is a separate version of model, + in which each floating-point parameter is the average of all the + parameters from the start of training. Each time we take the average, + we do: `model_avg = model * (average_period / batch_idx_train) + + model_avg * ((batch_idx_train - average_period) / batch_idx_train)`. + """, + ) + + parser.add_argument( + "--use-fp16", + type=str2bool, + default=False, + help="Whether to use half precision training.", + ) + + parser.add_argument( + "--delay-penalty", + type=float, + default=0.0, + help="""A constant value used to penalize symbol delay, + to encourage streaming models to emit symbols earlier. + See https://github.com/k2-fsa/k2/issues/955 and + https://arxiv.org/pdf/2211.00490.pdf for more details.""", + ) + + add_model_arguments(parser) + + return parser + + +def get_params() -> AttributeDict: + """Return a dict containing training parameters. + + All training related parameters that are not passed from the commandline + are saved in the variable `params`. + + Commandline options are merged into `params` after they are parsed, so + you can also access them via `params`. + + Explanation of options saved in `params`: + + - best_train_loss: Best training loss so far. It is used to select + the model that has the lowest training loss. It is + updated during the training. + + - best_valid_loss: Best validation loss so far. It is used to select + the model that has the lowest validation loss. It is + updated during the training. + + - best_train_epoch: It is the epoch that has the best training loss. + + - best_valid_epoch: It is the epoch that has the best validation loss. + + - batch_idx_train: Used to writing statistics to tensorboard. It + contains number of batches trained so far across + epochs. + + - log_interval: Print training loss if batch_idx % log_interval` is 0 + + - reset_interval: Reset statistics if batch_idx % reset_interval is 0 + + - valid_interval: Run validation if batch_idx % valid_interval is 0 + + - feature_dim: The model input dim. It has to match the one used + in computing features. + + - subsampling_factor: The subsampling factor for the model. + + - encoder_dim: Hidden dim for multi-head attention model. + + - num_decoder_layers: Number of decoder layer of transformer decoder. + + - warm_step: The warm_step for Noam optimizer. + """ + params = AttributeDict( + { + "best_train_loss": float("inf"), + "best_valid_loss": float("inf"), + "best_train_epoch": -1, + "best_valid_epoch": -1, + "batch_idx_train": 0, + "log_interval": 50, + "reset_interval": 200, + "valid_interval": 3000, # For the 100h subset, use 800 + # parameters for conformer + "feature_dim": 80, + "subsampling_factor": 4, + # parameters for Noam + "model_warm_step": 3000, # arg given to model, not for lrate + "env_info": get_env_info(), + } + ) + + return params + + +def get_encoder_model(params: AttributeDict) -> nn.Module: + # TODO: We can add an option to switch between Conformer and Transformer + encoder = Conformer( + num_features=params.feature_dim, + subsampling_factor=params.subsampling_factor, + d_model=params.encoder_dim, + nhead=params.nhead, + dim_feedforward=params.dim_feedforward, + num_encoder_layers=params.num_encoder_layers, + dynamic_chunk_training=params.dynamic_chunk_training, + short_chunk_size=params.short_chunk_size, + num_left_chunks=params.num_left_chunks, + causal=params.causal_convolution, + ) + return encoder + + +def get_decoder_model(params: AttributeDict) -> nn.Module: + decoder = Decoder( + vocab_size=params.vocab_size, + decoder_dim=params.decoder_dim, + blank_id=params.blank_id, + context_size=params.context_size, + ) + return decoder + + +def get_joiner_model(params: AttributeDict) -> nn.Module: + joiner = Joiner( + encoder_dim=params.encoder_dim, + decoder_dim=params.decoder_dim, + joiner_dim=params.joiner_dim, + vocab_size=params.vocab_size, + ) + return joiner + + +def get_transducer_model(params: AttributeDict) -> nn.Module: + encoder = get_encoder_model(params) + decoder = get_decoder_model(params) + joiner = get_joiner_model(params) + + model = Transducer( + encoder=encoder, + decoder=decoder, + joiner=joiner, + encoder_dim=params.encoder_dim, + decoder_dim=params.decoder_dim, + joiner_dim=params.joiner_dim, + vocab_size=params.vocab_size, + ) + return model + + +def load_checkpoint_if_available( + params: AttributeDict, + model: nn.Module, + model_avg: nn.Module = None, + optimizer: Optional[torch.optim.Optimizer] = None, + scheduler: Optional[LRSchedulerType] = None, +) -> Optional[Dict[str, Any]]: + """Load checkpoint from file. + + If params.start_batch is positive, it will load the checkpoint from + `params.exp_dir/checkpoint-{params.start_batch}.pt`. Otherwise, if + params.start_epoch is larger than 1, it will load the checkpoint from + `params.start_epoch - 1`. + + Apart from loading state dict for `model` and `optimizer` it also updates + `best_train_epoch`, `best_train_loss`, `best_valid_epoch`, + and `best_valid_loss` in `params`. + + Args: + params: + The return value of :func:`get_params`. + model: + The training model. + model_avg: + The stored model averaged from the start of training. + optimizer: + The optimizer that we are using. + scheduler: + The scheduler that we are using. + Returns: + Return a dict containing previously saved training info. + """ + if params.start_batch > 0: + filename = params.exp_dir / f"checkpoint-{params.start_batch}.pt" + elif params.start_epoch > 1: + filename = params.exp_dir / f"epoch-{params.start_epoch-1}.pt" + else: + return None + + assert filename.is_file(), f"{filename} does not exist!" + + saved_params = load_checkpoint( + filename, + model=model, + model_avg=model_avg, + optimizer=optimizer, + scheduler=scheduler, + ) + + keys = [ + "best_train_epoch", + "best_valid_epoch", + "batch_idx_train", + "best_train_loss", + "best_valid_loss", + ] + for k in keys: + params[k] = saved_params[k] + + if params.start_batch > 0: + if "cur_epoch" in saved_params: + params["start_epoch"] = saved_params["cur_epoch"] + + return saved_params + + +def save_checkpoint( + params: AttributeDict, + model: Union[nn.Module, DDP], + model_avg: Optional[nn.Module] = None, + optimizer: Optional[torch.optim.Optimizer] = None, + scheduler: Optional[LRSchedulerType] = None, + sampler: Optional[CutSampler] = None, + scaler: Optional[GradScaler] = None, + rank: int = 0, +) -> None: + """Save model, optimizer, scheduler and training stats to file. + + Args: + params: + It is returned by :func:`get_params`. + model: + The training model. + model_avg: + The stored model averaged from the start of training. + optimizer: + The optimizer used in the training. + sampler: + The sampler for the training dataset. + scaler: + The scaler used for mix precision training. + """ + if rank != 0: + return + filename = params.exp_dir / f"epoch-{params.cur_epoch}.pt" + save_checkpoint_impl( + filename=filename, + model=model, + model_avg=model_avg, + params=params, + optimizer=optimizer, + scheduler=scheduler, + sampler=sampler, + scaler=scaler, + rank=rank, + ) + + if params.best_train_epoch == params.cur_epoch: + best_train_filename = params.exp_dir / "best-train-loss.pt" + copyfile(src=filename, dst=best_train_filename) + + if params.best_valid_epoch == params.cur_epoch: + best_valid_filename = params.exp_dir / "best-valid-loss.pt" + copyfile(src=filename, dst=best_valid_filename) + + +def compute_loss( + params: AttributeDict, + model: Union[nn.Module, DDP], + sp: spm.SentencePieceProcessor, + batch: dict, + is_training: bool, + warmup: float = 1.0, +) -> Tuple[Tensor, MetricsTracker]: + """ + Compute RNN-T loss given the model and its inputs. + + Args: + params: + Parameters for training. See :func:`get_params`. + model: + The model for training. It is an instance of Conformer in our case. + batch: + A batch of data. See `lhotse.dataset.K2SpeechRecognitionDataset()` + for the content in it. + is_training: + True for training. False for validation. When it is True, this + function enables autograd during computation; when it is False, it + disables autograd. + warmup: a floating point value which increases throughout training; + values >= 1.0 are fully warmed up and have all modules present. + """ + device = model.device if isinstance(model, DDP) else next(model.parameters()).device + feature = batch["inputs"] + # at entry, feature is (N, T, C) + assert feature.ndim == 3 + feature = feature.to(device) + + supervisions = batch["supervisions"] + feature_lens = supervisions["num_frames"].to(device) + + texts = batch["supervisions"]["text"] + y = sp.encode(texts, out_type=int) + y = k2.RaggedTensor(y).to(device) + + with torch.set_grad_enabled(is_training): + simple_loss, pruned_loss = model( + x=feature, + x_lens=feature_lens, + y=y, + prune_range=params.prune_range, + am_scale=params.am_scale, + lm_scale=params.lm_scale, + warmup=warmup, + reduction="none", + delay_penalty=params.delay_penalty if warmup >= 2.0 else 0, + ) + simple_loss_is_finite = torch.isfinite(simple_loss) + pruned_loss_is_finite = torch.isfinite(pruned_loss) + is_finite = simple_loss_is_finite & pruned_loss_is_finite + if not torch.all(is_finite): + logging.info( + "Not all losses are finite!\n" + f"simple_loss: {simple_loss}\n" + f"pruned_loss: {pruned_loss}" + ) + display_and_save_batch(batch, params=params, sp=sp) + simple_loss = simple_loss[simple_loss_is_finite] + pruned_loss = pruned_loss[pruned_loss_is_finite] + + # If the batch contains more than 10 utterances AND + # if either all simple_loss or pruned_loss is inf or nan, + # we stop the training process by raising an exception + if torch.all(~simple_loss_is_finite) or torch.all(~pruned_loss_is_finite): + raise ValueError( + "There are too many utterances in this batch " + "leading to inf or nan losses." + ) + + simple_loss = simple_loss.sum() + pruned_loss = pruned_loss.sum() + # after the main warmup step, we keep pruned_loss_scale small + # for the same amount of time (model_warm_step), to avoid + # overwhelming the simple_loss and causing it to diverge, + # in case it had not fully learned the alignment yet. + pruned_loss_scale = ( + 0.0 if warmup < 1.0 else (0.1 if warmup > 1.0 and warmup < 2.0 else 1.0) + ) + loss = params.simple_loss_scale * simple_loss + pruned_loss_scale * pruned_loss + + assert loss.requires_grad == is_training + + info = MetricsTracker() + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + # info["frames"] is an approximate number for two reasons: + # (1) The acutal subsampling factor is ((lens - 1) // 2 - 1) // 2 + # (2) If some utterances in the batch lead to inf/nan loss, they + # are filtered out. + info["frames"] = (feature_lens // params.subsampling_factor).sum().item() + + # `utt_duration` and `utt_pad_proportion` would be normalized by `utterances` # noqa + info["utterances"] = feature.size(0) + # averaged input duration in frames over utterances + info["utt_duration"] = feature_lens.sum().item() + # averaged padding proportion over utterances + info["utt_pad_proportion"] = ( + ((feature.size(1) - feature_lens) / feature.size(1)).sum().item() + ) + + # Note: We use reduction=sum while computing the loss. + info["loss"] = loss.detach().cpu().item() + info["simple_loss"] = simple_loss.detach().cpu().item() + info["pruned_loss"] = pruned_loss.detach().cpu().item() + + return loss, info + + +def compute_validation_loss( + params: AttributeDict, + model: Union[nn.Module, DDP], + sp: spm.SentencePieceProcessor, + valid_dl: torch.utils.data.DataLoader, + world_size: int = 1, +) -> MetricsTracker: + """Run the validation process.""" + model.eval() + + tot_loss = MetricsTracker() + + for batch_idx, batch in enumerate(valid_dl): + loss, loss_info = compute_loss( + params=params, + model=model, + sp=sp, + batch=batch, + is_training=False, + ) + assert loss.requires_grad is False + tot_loss = tot_loss + loss_info + + if world_size > 1: + tot_loss.reduce(loss.device) + + loss_value = tot_loss["loss"] / tot_loss["frames"] + if loss_value < params.best_valid_loss: + params.best_valid_epoch = params.cur_epoch + params.best_valid_loss = loss_value + + return tot_loss + + +def train_one_epoch( + params: AttributeDict, + model: Union[nn.Module, DDP], + optimizer: torch.optim.Optimizer, + scheduler: LRSchedulerType, + sp: spm.SentencePieceProcessor, + train_dl: torch.utils.data.DataLoader, + valid_dl: torch.utils.data.DataLoader, + scaler: GradScaler, + model_avg: Optional[nn.Module] = None, + tb_writer: Optional[SummaryWriter] = None, + world_size: int = 1, + rank: int = 0, +) -> None: + """Train the model for one epoch. + + The training loss from the mean of all frames is saved in + `params.train_loss`. It runs the validation process every + `params.valid_interval` batches. + + Args: + params: + It is returned by :func:`get_params`. + model: + The model for training. + optimizer: + The optimizer we are using. + scheduler: + The learning rate scheduler, we call step() every step. + train_dl: + Dataloader for the training dataset. + valid_dl: + Dataloader for the validation dataset. + scaler: + The scaler used for mix precision training. + model_avg: + The stored model averaged from the start of training. + tb_writer: + Writer to write log messages to tensorboard. + world_size: + Number of nodes in DDP training. If it is 1, DDP is disabled. + rank: + The rank of the node in DDP training. If no DDP is used, it should + be set to 0. + """ + model.train() + + tot_loss = MetricsTracker() + + for batch_idx, batch in enumerate(train_dl): + params.batch_idx_train += 1 + batch_size = len(batch["supervisions"]["text"]) + + try: + with torch.cuda.amp.autocast(enabled=params.use_fp16): + loss, loss_info = compute_loss( + params=params, + model=model, + sp=sp, + batch=batch, + is_training=True, + warmup=(params.batch_idx_train / params.model_warm_step), + ) + # summary stats + tot_loss = (tot_loss * (1 - 1 / params.reset_interval)) + loss_info + + # NOTE: We use reduction==sum and loss is computed over utterances + # in the batch and there is no normalization to it so far. + scaler.scale(loss).backward() + scheduler.step_batch(params.batch_idx_train) + scaler.step(optimizer) + scaler.update() + optimizer.zero_grad() + except: # noqa + display_and_save_batch(batch, params=params, sp=sp) + raise + + if params.print_diagnostics and batch_idx == 5: + return + + if ( + rank == 0 + and params.batch_idx_train > 0 + and params.batch_idx_train % params.average_period == 0 + ): + update_averaged_model( + params=params, + model_cur=model, + model_avg=model_avg, + ) + + if ( + params.batch_idx_train > 0 + and params.batch_idx_train % params.save_every_n == 0 + ): + save_checkpoint_with_global_batch_idx( + out_dir=params.exp_dir, + global_batch_idx=params.batch_idx_train, + model=model, + model_avg=model_avg, + params=params, + optimizer=optimizer, + scheduler=scheduler, + sampler=train_dl.sampler, + scaler=scaler, + rank=rank, + ) + remove_checkpoints( + out_dir=params.exp_dir, + topk=params.keep_last_k, + rank=rank, + ) + + if batch_idx % params.log_interval == 0: + cur_lr = scheduler.get_last_lr()[0] + logging.info( + f"Epoch {params.cur_epoch}, " + f"batch {batch_idx}, loss[{loss_info}], " + f"tot_loss[{tot_loss}], batch size: {batch_size}, " + f"lr: {cur_lr:.2e}" + ) + + if tb_writer is not None: + tb_writer.add_scalar( + "train/learning_rate", cur_lr, params.batch_idx_train + ) + + loss_info.write_summary( + tb_writer, "train/current_", params.batch_idx_train + ) + tot_loss.write_summary(tb_writer, "train/tot_", params.batch_idx_train) + + if batch_idx > 0 and batch_idx % params.valid_interval == 0: + logging.info("Computing validation loss") + valid_info = compute_validation_loss( + params=params, + model=model, + sp=sp, + valid_dl=valid_dl, + world_size=world_size, + ) + model.train() + logging.info(f"Epoch {params.cur_epoch}, validation: {valid_info}") + if tb_writer is not None: + valid_info.write_summary( + tb_writer, "train/valid_", params.batch_idx_train + ) + + loss_value = tot_loss["loss"] / tot_loss["frames"] + params.train_loss = loss_value + if params.train_loss < params.best_train_loss: + params.best_train_epoch = params.cur_epoch + params.best_train_loss = params.train_loss + + +def run(rank, world_size, args): + """ + Args: + rank: + It is a value between 0 and `world_size-1`, which is + passed automatically by `mp.spawn()` in :func:`main`. + The node with rank 0 is responsible for saving checkpoint. + world_size: + Number of GPUs for DDP training. + args: + The return value of get_parser().parse_args() + """ + params = get_params() + params.update(vars(args)) + if params.full_libri is False: + params.valid_interval = 1600 + + fix_random_seed(params.seed) + if world_size > 1: + setup_dist(rank, world_size, params.master_port) + + setup_logger(f"{params.exp_dir}/log/log-train") + logging.info("Training started") + + if args.tensorboard and rank == 0: + tb_writer = SummaryWriter(log_dir=f"{params.exp_dir}/tensorboard") + else: + tb_writer = None + + device = torch.device("cpu") + if torch.cuda.is_available(): + device = torch.device("cuda", rank) + logging.info(f"Device: {device}") + + sp = spm.SentencePieceProcessor() + sp.load(params.bpe_model) + + # is defined in local/train_bpe_model.py + params.blank_id = sp.piece_to_id("") + params.vocab_size = sp.get_piece_size() + + if params.dynamic_chunk_training: + assert ( + params.causal_convolution + ), "dynamic_chunk_training requires causal convolution" + + logging.info(params) + + logging.info("About to create model") + model = get_transducer_model(params) + + num_param = sum([p.numel() for p in model.parameters()]) + logging.info(f"Number of model parameters: {num_param}") + + assert params.save_every_n >= params.average_period + model_avg: Optional[nn.Module] = None + if rank == 0: + # model_avg is only used with rank 0 + model_avg = copy.deepcopy(model) + + assert params.start_epoch > 0, params.start_epoch + checkpoints = load_checkpoint_if_available( + params=params, model=model, model_avg=model_avg + ) + + model.to(device) + if world_size > 1: + logging.info("Using DDP") + model = DDP(model, device_ids=[rank]) + + optimizer = Eve(model.parameters(), lr=params.initial_lr) + + scheduler = Eden(optimizer, params.lr_batches, params.lr_epochs) + + if checkpoints and "optimizer" in checkpoints: + logging.info("Loading optimizer state dict") + optimizer.load_state_dict(checkpoints["optimizer"]) + + if ( + checkpoints + and "scheduler" in checkpoints + and checkpoints["scheduler"] is not None + ): + logging.info("Loading scheduler state dict") + scheduler.load_state_dict(checkpoints["scheduler"]) + + if params.print_diagnostics: + opts = diagnostics.TensorDiagnosticOptions( + 2**22 + ) # allow 4 megabytes per sub-module + diagnostic = diagnostics.attach_diagnostics(model, opts) + + librispeech = LibriSpeechAsrDataModule(args) + + if params.full_libri: + train_cuts = librispeech.train_all_shuf_cuts() + else: + train_cuts = librispeech.train_clean_100_cuts() + + def remove_short_and_long_utt(c: Cut): + # Keep only utterances with duration between 1 second and 20 seconds + # + # Caution: There is a reason to select 20.0 here. Please see + # ../local/display_manifest_statistics.py + # + # You should use ../local/display_manifest_statistics.py to get + # an utterance duration distribution for your dataset to select + # the threshold + if c.duration < 1.0 or c.duration > 20.0: + #logging.warning( + # f"Exclude cut with ID {c.id} from training. Duration: {c.duration}" + #) + return False + + # In pruned RNN-T, we require that T >= S + # where T is the number of feature frames after subsampling + # and S is the number of tokens in the utterance + + # In ./conformer.py, the conv module uses the following expression + # for subsampling + T = ((c.num_frames - 1) // 2 - 1) // 2 + tokens = sp.encode(c.supervisions[0].text, out_type=str) + + if T < len(tokens): + logging.warning( + f"Exclude cut with ID {c.id} from training. " + f"Number of frames (before subsampling): {c.num_frames}. " + f"Number of frames (after subsampling): {T}. " + f"Text: {c.supervisions[0].text}. " + f"Tokens: {tokens}. " + f"Number of tokens: {len(tokens)}" + ) + return False + + return True + + train_cuts = train_cuts.filter(remove_short_and_long_utt) + + if params.start_batch > 0 and checkpoints and "sampler" in checkpoints: + # We only load the sampler's state dict when it loads a checkpoint + # saved in the middle of an epoch + sampler_state_dict = checkpoints["sampler"] + else: + sampler_state_dict = None + + train_dl = librispeech.train_dataloaders( + train_cuts, sampler_state_dict=sampler_state_dict + ) + + valid_cuts = librispeech.dev_clean_cuts() + valid_cuts += librispeech.dev_other_cuts() + valid_dl = librispeech.valid_dataloaders(valid_cuts) + + ''' + if params.start_batch <= 0 and not params.print_diagnostics: + scan_pessimistic_batches_for_oom( + model=model, + train_dl=train_dl, + optimizer=optimizer, + sp=sp, + params=params, + warmup=0.0 if params.start_epoch == 1 else 1.0, + ) + ''' + + scaler = GradScaler(enabled=params.use_fp16) + if checkpoints and "grad_scaler" in checkpoints: + logging.info("Loading grad scaler state dict") + scaler.load_state_dict(checkpoints["grad_scaler"]) + + for epoch in range(params.start_epoch, params.num_epochs + 1): + scheduler.step_epoch(epoch - 1) + fix_random_seed(params.seed + epoch - 1) + train_dl.sampler.set_epoch(epoch - 1) + + if tb_writer is not None: + tb_writer.add_scalar("train/epoch", epoch, params.batch_idx_train) + + params.cur_epoch = epoch + + train_one_epoch( + params=params, + model=model, + model_avg=model_avg, + optimizer=optimizer, + scheduler=scheduler, + sp=sp, + train_dl=train_dl, + valid_dl=valid_dl, + scaler=scaler, + tb_writer=tb_writer, + world_size=world_size, + rank=rank, + ) + + if params.print_diagnostics: + diagnostic.print_diagnostics() + break + + save_checkpoint( + params=params, + model=model, + model_avg=model_avg, + optimizer=optimizer, + scheduler=scheduler, + sampler=train_dl.sampler, + scaler=scaler, + rank=rank, + ) + + logging.info("Done!") + + if world_size > 1: + torch.distributed.barrier() + cleanup_dist() + + +def scan_pessimistic_batches_for_oom( + model: Union[nn.Module, DDP], + train_dl: torch.utils.data.DataLoader, + optimizer: torch.optim.Optimizer, + sp: spm.SentencePieceProcessor, + params: AttributeDict, + warmup: float, +): + from lhotse.dataset import find_pessimistic_batches + + logging.info( + "Sanity check -- see if any of the batches in epoch 1 would cause OOM." + ) + batches, crit_values = find_pessimistic_batches(train_dl.sampler) + for criterion, cuts in batches.items(): + batch = train_dl.dataset[cuts] + try: + with torch.cuda.amp.autocast(enabled=params.use_fp16): + loss, _ = compute_loss( + params=params, + model=model, + sp=sp, + batch=batch, + is_training=True, + warmup=warmup, + ) + loss.backward() + optimizer.step() + optimizer.zero_grad() + except Exception as e: + if "CUDA out of memory" in str(e): + logging.error( + "Your GPU ran out of memory with the current " + "max_duration setting. We recommend decreasing " + "max_duration and trying again.\n" + f"Failing criterion: {criterion} " + f"(={crit_values[criterion]}) ..." + ) + display_and_save_batch(batch, params=params, sp=sp) + raise + + +def main(): + parser = get_parser() + LibriSpeechAsrDataModule.add_arguments(parser) + args = parser.parse_args() + args.exp_dir = Path(args.exp_dir) + + world_size = args.world_size + assert world_size >= 1 + if world_size > 1: + mp.spawn(run, args=(world_size, args), nprocs=world_size, join=True) + else: + run(rank=0, world_size=1, args=args) + + +torch.set_num_threads(1) +torch.set_num_interop_threads(1) + +if __name__ == "__main__": + main()