From 116d0cf26dd323a257c5785f213500c0dc13cb8c Mon Sep 17 00:00:00 2001 From: Quandwang Date: Fri, 22 Jul 2022 15:31:25 +0800 Subject: [PATCH] CTC attention model with reworked Conformer encoder and reworked Transformer decoder (#462) * ctc attention model with reworked conformer encoder and reworked transformer decoder * remove unnecessary func * resolve flake8 conflicts * fix typos and modify the expr of ScaledEmbedding * use original beam size * minor changes to the scripts * add rnn lm decoding * minor changes * check whether q k v weight is None * check whether q k v weight is None * check whether q k v weight is None * style correction * update results * update results * upload the decoding results of rnn-lm to the RESULTS * upload the decoding results of rnn-lm to the RESULTS * Update egs/librispeech/ASR/RESULTS.md Co-authored-by: Fangjun Kuang * Update egs/librispeech/ASR/RESULTS.md Co-authored-by: Fangjun Kuang * Update egs/librispeech/ASR/RESULTS.md Co-authored-by: Fangjun Kuang Co-authored-by: Fangjun Kuang --- .flake8 | 6 +- egs/librispeech/ASR/RESULTS.md | 114 +- .../ASR/conformer_ctc2/__init__.py | 1 + .../ASR/conformer_ctc2/asr_datamodule.py | 1 + .../ASR/conformer_ctc2/attention.py | 252 ++++ .../ASR/conformer_ctc2/conformer.py | 964 ++++++++++++++ egs/librispeech/ASR/conformer_ctc2/decode.py | 996 +++++++++++++++ egs/librispeech/ASR/conformer_ctc2/export.py | 281 +++++ .../ASR/conformer_ctc2/label_smoothing.py | 1 + egs/librispeech/ASR/conformer_ctc2/optim.py | 1 + egs/librispeech/ASR/conformer_ctc2/scaling.py | 1 + .../ASR/conformer_ctc2/subsampling.py | 121 ++ egs/librispeech/ASR/conformer_ctc2/train.py | 1119 +++++++++++++++++ .../ASR/conformer_ctc2/transformer.py | 1092 ++++++++++++++++ .../pruned_transducer_stateless2/scaling.py | 3 +- 15 files changed, 4949 insertions(+), 4 deletions(-) create mode 120000 egs/librispeech/ASR/conformer_ctc2/__init__.py create mode 120000 egs/librispeech/ASR/conformer_ctc2/asr_datamodule.py create mode 100644 egs/librispeech/ASR/conformer_ctc2/attention.py create mode 100644 egs/librispeech/ASR/conformer_ctc2/conformer.py create mode 100755 egs/librispeech/ASR/conformer_ctc2/decode.py create mode 100755 egs/librispeech/ASR/conformer_ctc2/export.py create mode 120000 egs/librispeech/ASR/conformer_ctc2/label_smoothing.py create mode 120000 egs/librispeech/ASR/conformer_ctc2/optim.py create mode 120000 egs/librispeech/ASR/conformer_ctc2/scaling.py create mode 100644 egs/librispeech/ASR/conformer_ctc2/subsampling.py create mode 100755 egs/librispeech/ASR/conformer_ctc2/train.py create mode 100644 egs/librispeech/ASR/conformer_ctc2/transformer.py diff --git a/.flake8 b/.flake8 index b2eb2e943..cbf0d8484 100644 --- a/.flake8 +++ b/.flake8 @@ -4,12 +4,14 @@ statistics=true max-line-length = 80 per-file-ignores = # line too long - icefall/diagnostics.py: E501 + icefall/diagnostics.py: E501, egs/*/ASR/*/conformer.py: E501, egs/*/ASR/pruned_transducer_stateless*/*.py: E501, egs/*/ASR/*/optim.py: E501, egs/*/ASR/*/scaling.py: E501, - egs/librispeech/ASR/conv_emformer_transducer_stateless*/*.py: E501, E203 + egs/librispeech/ASR/conv_emformer_transducer_stateless*/*.py: E501, E203, + egs/librispeech/ASR/conformer_ctc2/*py: E501, + egs/librispeech/ASR/RESULTS.md: E999, # invalid escape sequence (cause by tex formular), W605 icefall/utils.py: E501, W605 diff --git a/egs/librispeech/ASR/RESULTS.md b/egs/librispeech/ASR/RESULTS.md index d4096884b..b10ae98e6 100644 --- a/egs/librispeech/ASR/RESULTS.md +++ b/egs/librispeech/ASR/RESULTS.md @@ -1,6 +1,6 @@ ## Results -### LibriSpeech BPE training results (Pruned Stateless Conv-Emformer RNN-T 2) +#### LibriSpeech BPE training results (Pruned Stateless Conv-Emformer RNN-T 2) [conv_emformer_transducer_stateless2](./conv_emformer_transducer_stateless2) @@ -1998,6 +1998,118 @@ avg=11 You can find the tensorboard log at: +### LibriSpeech BPE training results (Conformer-CTC 2) + +#### [conformer_ctc2](./conformer_ctc2) + +#### 2022-07-21 + +It implements a 'reworked' version of CTC attention model. +As demenstrated by pruned_transducer_stateless2, reworked Conformer model has superior performance compared to the original Conformer. +So in this modified version of CTC attention model, it has the reworked Conformer as the encoder and the reworked Transformer as the decoder. +conformer_ctc2 also integrates with the idea of the 'averaging models' in pruned_transducer_stateless4. + +The WERs on comparisons with a baseline model, for the librispeech test dataset, are listed as below. + +The baseline model is the original conformer CTC attention model trained with icefall/egs/librispeech/ASR/conformer_ctc. +The model is downloaded from . +This model has 12 layers of Conformer encoder layers and 6 Transformer decoder layers. +Number of model parameters is 109,226,120. +It has been trained with 90 epochs with full Librispeech dataset. + +For this reworked CTC attention model, it has 12 layers of reworked Conformer encoder layers and 6 reworked Transformer decoder layers. +Number of model parameters is 103,071,035. +With full Librispeech data set, it was trained for **only** 30 epochs because the reworked model would converge much faster. +Please refer to to see the loss convergence curve. +Please find the above trained model at in huggingface. + +The decoding configuration for the reworked model is --epoch 30, --avg 8, --use-averaged-model True, which is the best after searching. + +| WER | reworked ctc attention | with --epoch 30 --avg 8 --use-averaged-model True | | ctc attention| with --epoch 77 --avg 55 | | +|------------------------|-------|------|------|------|------|-----| +| test sets | test-clean | test-other | Avg | test-clean | test-other | Avg | +| ctc-greedy-search | 2.98% | 7.14%| 5.06%| 2.90%| 7.47%| 5.19%| +| ctc-decoding | 2.98% | 7.14%| 5.06%| 2.90%| 7.47%| 5.19%| +| 1best | 2.93% | 6.37%| 4.65%| 2.70%| 6.49%| 4.60%| +| nbest | 2.94% | 6.39%| 4.67%| 2.70%| 6.48%| 4.59%| +| nbest-rescoring | 2.68% | 5.77%| 4.23%| 2.55%| 6.07%| 4.31%| +| whole-lattice-rescoring| 2.66% | 5.76%| 4.21%| 2.56%| 6.04%| 4.30%| +| attention-decoder | 2.59% | 5.54%| 4.07%| 2.41%| 5.77%| 4.09%| +| nbest-oracle | 1.53% | 3.47%| 2.50%| 1.69%| 4.02%| 2.86%| +| rnn-lm | 2.37% | 4.98%| 3.68%| 2.31%| 5.35%| 3.83%| + + + +conformer_ctc2 also implements the CTC greedy search decoding, it has the identical WERs with the CTC-decoding method. +For other decoding methods, the average WER of the two test sets with the two models is similar. +Except for the 1best and nbest methods, the overall performance of reworked model is better than the baseline model. + + +To reproduce the above result, use the following commands. + +The training commands are: + +```bash + WORLD_SIZE=8 + export CUDA_VISIBLE_DEVICES="0,1,2,3,4,5,6,7" + ./conformer_ctc2/train.py \ + --manifest-dir data/fbank \ + --exp-dir conformer_ctc2/exp \ + --full-libri 1 \ + --spec-aug-time-warp-factor 80 \ + --max-duration 300 \ + --world-size ${WORLD_SIZE} \ + --start-epoch 1 \ + --num-epochs 30 \ + --att-rate 0.7 \ + --num-decoder-layers 6 +``` + + +And the following commands are for decoding: + +```bash + + +for method in ctc-greedy-search ctc-decoding 1best nbest-oracle; do + python3 ./conformer_ctc2/decode.py \ + --exp-dir conformer_ctc2/exp \ + --use-averaged-model True --epoch 30 --avg 8 --max-duration 200 --method $method +done + +for method in nbest nbest-rescoring whole-lattice-rescoring attention-decoder ; do + python3 ./conformer_ctc2/decode.py \ + --exp-dir conformer_ctc2/exp \ + --use-averaged-model True --epoch 30 --avg 8 --max-duration 20 --method $method +done + +rnn_dir=$(git rev-parse --show-toplevel)/icefall/rnn_lm +./conformer_ctc2/decode.py \ + --exp-dir conformer_ctc2/exp \ + --lang-dir data/lang_bpe_500 \ + --lm-dir data/lm \ + --max-duration 30 \ + --concatenate-cuts 0 \ + --bucketing-sampler 1 \ + --num-paths 1000 \ + --use-averaged-model True \ + --epoch 30 \ + --avg 8 \ + --nbest-scale 0.5 \ + --rnn-lm-exp-dir ${rnn_dir}/exp \ + --rnn-lm-epoch 29 \ + --rnn-lm-avg 3 \ + --rnn-lm-embedding-dim 2048 \ + --rnn-lm-hidden-dim 2048 \ + --rnn-lm-num-layers 3 \ + --rnn-lm-tie-weights true \ + --method rnn-lm +``` + +You can find the RNN-LM pre-trained model at + + + ### LibriSpeech BPE training results (Conformer-CTC) #### 2021-11-09 diff --git a/egs/librispeech/ASR/conformer_ctc2/__init__.py b/egs/librispeech/ASR/conformer_ctc2/__init__.py new file mode 120000 index 000000000..b24e5e357 --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/__init__.py @@ -0,0 +1 @@ +../pruned_transducer_stateless2/__init__.py \ No newline at end of file diff --git a/egs/librispeech/ASR/conformer_ctc2/asr_datamodule.py b/egs/librispeech/ASR/conformer_ctc2/asr_datamodule.py new file mode 120000 index 000000000..a074d6085 --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/asr_datamodule.py @@ -0,0 +1 @@ +../pruned_transducer_stateless2/asr_datamodule.py \ No newline at end of file diff --git a/egs/librispeech/ASR/conformer_ctc2/attention.py b/egs/librispeech/ASR/conformer_ctc2/attention.py new file mode 100644 index 000000000..1375d7245 --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/attention.py @@ -0,0 +1,252 @@ +# Copyright 2022 Xiaomi Corp. (author: Quandong Wang) +# +# 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 Optional, Tuple + +import torch +import torch.nn as nn +from torch import Tensor +from torch.nn.init import xavier_normal_ + +from scaling import ScaledLinear + + +class MultiheadAttention(nn.Module): + r"""Allows the model to jointly attend to information + from different representation subspaces. + See `Attention Is All You Need `_. + + .. math:: + \text{MultiHead}(Q, K, V) = \text{Concat}(head_1,\dots,head_h)W^O + + where :math:`head_i = \text{Attention}(QW_i^Q, KW_i^K, VW_i^V)`. + + Args: + embed_dim: Total dimension of the model. + num_heads: Number of parallel attention heads. Note that ``embed_dim`` will be split + across ``num_heads`` (i.e. each head will have dimension ``embed_dim // num_heads``). + dropout: Dropout probability on ``attn_output_weights``. Default: ``0.0`` (no dropout). + bias: If specified, adds bias to input / output projection layers. Default: ``True``. + add_bias_kv: If specified, adds bias to the key and value sequences at dim=0. Default: ``False``. + add_zero_attn: If specified, adds a new batch of zeros to the key and value sequences at dim=1. + Default: ``False``. + kdim: Total number of features for keys. Default: ``None`` (uses ``kdim=embed_dim``). + vdim: Total number of features for values. Default: ``None`` (uses ``vdim=embed_dim``). + batch_first: If ``True``, then the input and output tensors are provided + as (batch, seq, feature). Default: ``False`` (seq, batch, feature). + + Examples:: + + >>> multihead_attn = nn.MultiheadAttention(embed_dim, num_heads) + >>> attn_output, attn_output_weights = multihead_attn(query, key, value) + """ + __constants__ = ["batch_first"] + bias_k: Optional[torch.Tensor] + bias_v: Optional[torch.Tensor] + + def __init__( + self, + embed_dim, + num_heads, + dropout=0.0, + bias=True, + add_bias_kv=False, + add_zero_attn=False, + kdim=None, + vdim=None, + batch_first=False, + device=None, + dtype=None, + ) -> None: + factory_kwargs = {"device": device, "dtype": dtype} + super(MultiheadAttention, self).__init__() + self.embed_dim = embed_dim + self.kdim = kdim if kdim is not None else embed_dim + self.vdim = vdim if vdim is not None else embed_dim + self._qkv_same_embed_dim = ( + self.kdim == embed_dim and self.vdim == embed_dim + ) + + self.num_heads = num_heads + self.dropout = dropout + self.batch_first = batch_first + self.head_dim = embed_dim // num_heads + assert ( + self.head_dim * num_heads == self.embed_dim + ), "embed_dim must be divisible by num_heads" + + if self._qkv_same_embed_dim is False: + self.q_proj_weight = ScaledLinear(embed_dim, embed_dim, bias=bias) + self.k_proj_weight = ScaledLinear(self.kdim, embed_dim, bias=bias) + self.v_proj_weight = ScaledLinear(self.vdim, embed_dim, bias=bias) + self.register_parameter("in_proj_weight", None) + else: + self.in_proj_weight = ScaledLinear( + embed_dim, 3 * embed_dim, bias=bias + ) + self.register_parameter("q_proj_weight", None) + self.register_parameter("k_proj_weight", None) + self.register_parameter("v_proj_weight", None) + + if not bias: + self.register_parameter("in_proj_bias", None) + + self.out_proj = ScaledLinear(embed_dim, embed_dim, bias=bias) + + if add_bias_kv: + self.bias_k = nn.Parameter( + torch.empty((1, 1, embed_dim), **factory_kwargs) + ) + self.bias_v = nn.Parameter( + torch.empty((1, 1, embed_dim), **factory_kwargs) + ) + else: + self.bias_k = self.bias_v = None + + self.add_zero_attn = add_zero_attn + + self._reset_parameters() + + def _reset_parameters(self): + if self.bias_k is not None: + xavier_normal_(self.bias_k) + if self.bias_v is not None: + xavier_normal_(self.bias_v) + + def __setstate__(self, state): + # Support loading old MultiheadAttention checkpoints generated by v1.1.0 + if "_qkv_same_embed_dim" not in state: + state["_qkv_same_embed_dim"] = True + + super(MultiheadAttention, self).__setstate__(state) + + def forward( + self, + query: Tensor, + key: Tensor, + value: Tensor, + key_padding_mask: Optional[Tensor] = None, + need_weights: bool = True, + attn_mask: Optional[Tensor] = None, + ) -> Tuple[Tensor, Optional[Tensor]]: + r""" + Args: + query: Query embeddings of shape :math:`(L, N, E_q)` when ``batch_first=False`` or :math:`(N, L, E_q)` + when ``batch_first=True``, where :math:`L` is the target sequence length, :math:`N` is the batch size, + and :math:`E_q` is the query embedding dimension ``embed_dim``. Queries are compared against + key-value pairs to produce the output. See "Attention Is All You Need" for more details. + key: Key embeddings of shape :math:`(S, N, E_k)` when ``batch_first=False`` or :math:`(N, S, E_k)` when + ``batch_first=True``, where :math:`S` is the source sequence length, :math:`N` is the batch size, and + :math:`E_k` is the key embedding dimension ``kdim``. See "Attention Is All You Need" for more details. + value: Value embeddings of shape :math:`(S, N, E_v)` when ``batch_first=False`` or :math:`(N, S, E_v)` when + ``batch_first=True``, where :math:`S` is the source sequence length, :math:`N` is the batch size, and + :math:`E_v` is the value embedding dimension ``vdim``. See "Attention Is All You Need" for more details. + key_padding_mask: If specified, a mask of shape :math:`(N, S)` indicating which elements within ``key`` + to ignore for the purpose of attention (i.e. treat as "padding"). Binary and byte masks are supported. + For a binary mask, a ``True`` value indicates that the corresponding ``key`` value will be ignored for + the purpose of attention. For a byte mask, a non-zero value indicates that the corresponding ``key`` + value will be ignored. + need_weights: If specified, returns ``attn_output_weights`` in addition to ``attn_outputs``. + Default: ``True``. + attn_mask: If specified, a 2D or 3D mask preventing attention to certain positions. Must be of shape + :math:`(L, S)` or :math:`(N\cdot\text{num\_heads}, L, S)`, where :math:`N` is the batch size, + :math:`L` is the target sequence length, and :math:`S` is the source sequence length. A 2D mask will be + broadcasted across the batch while a 3D mask allows for a different mask for each entry in the batch. + Binary, byte, and float masks are supported. For a binary mask, a ``True`` value indicates that the + corresponding position is not allowed to attend. For a byte mask, a non-zero value indicates that the + corresponding position is not allowed to attend. For a float mask, the mask values will be added to + the attention weight. + + Outputs: + - **attn_output** - Attention outputs of shape :math:`(L, N, E)` when ``batch_first=False`` or + :math:`(N, L, E)` when ``batch_first=True``, where :math:`L` is the target sequence length, :math:`N` is + the batch size, and :math:`E` is the embedding dimension ``embed_dim``. + - **attn_output_weights** - Attention output weights of shape :math:`(N, L, S)`, where :math:`N` is the batch + size, :math:`L` is the target sequence length, and :math:`S` is the source sequence length. Only returned + when ``need_weights=True``. + """ + if self.batch_first: + query, key, value = [x.transpose(1, 0) for x in (query, key, value)] + + if not self._qkv_same_embed_dim: + q_proj_weight = ( + self.q_proj_weight.get_weight() + if self.q_proj_weight is not None + else None + ) + k_proj_weight = ( + self.k_proj_weight.get_weight() + if self.k_proj_weight is not None + else None + ) + v_proj_weight = ( + self.v_proj_weight.get_weight() + if self.v_proj_weight is not None + else None + ) + ( + attn_output, + attn_output_weights, + ) = nn.functional.multi_head_attention_forward( + query, + key, + value, + self.embed_dim, + self.num_heads, + self.in_proj_weight.get_weight(), + self.in_proj_weight.get_bias(), + self.bias_k, + self.bias_v, + self.add_zero_attn, + 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, + use_separate_proj_weight=True, + q_proj_weight=q_proj_weight, + k_proj_weight=k_proj_weight, + v_proj_weight=v_proj_weight, + ) + else: + ( + attn_output, + attn_output_weights, + ) = nn.functional.multi_head_attention_forward( + query, + key, + value, + self.embed_dim, + self.num_heads, + self.in_proj_weight.get_weight(), + self.in_proj_weight.get_bias(), + self.bias_k, + self.bias_v, + self.add_zero_attn, + 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, + ) + if self.batch_first: + return attn_output.transpose(1, 0), attn_output_weights + else: + return attn_output, attn_output_weights diff --git a/egs/librispeech/ASR/conformer_ctc2/conformer.py b/egs/librispeech/ASR/conformer_ctc2/conformer.py new file mode 100644 index 000000000..fb11a5fc8 --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/conformer.py @@ -0,0 +1,964 @@ +#!/usr/bin/env python3 +# Copyright (c) 2021 University of Chinese Academy of Sciences (author: Han Zhu) +# 2022 Xiaomi Corp. (author: Quandong Wang) +# +# 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 Optional, Tuple + +import torch +from scaling import ( + ActivationBalancer, + BasicNorm, + DoubleSwish, + ScaledConv1d, + ScaledLinear, +) +from torch import Tensor, nn +from subsampling import Conv2dSubsampling + +from transformer import Supervisions, Transformer, encoder_padding_mask + + +class Conformer(Transformer): + """ + Args: + num_features (int): Number of input features + num_classes (int): Number of output classes + 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 + num_decoder_layers (int): number of decoder layers + dropout (float): dropout rate + layer_dropout (float): layer-dropout rate. + cnn_module_kernel (int): Kernel size of convolution module + vgg_frontend (bool): whether to use vgg frontend. + """ + + def __init__( + self, + num_features: int, + num_classes: int, + subsampling_factor: int = 4, + d_model: int = 256, + nhead: int = 4, + dim_feedforward: int = 2048, + num_encoder_layers: int = 12, + num_decoder_layers: int = 6, + dropout: float = 0.1, + layer_dropout: float = 0.075, + cnn_module_kernel: int = 31, + ) -> None: + super(Conformer, self).__init__( + num_features=num_features, + num_classes=num_classes, + subsampling_factor=subsampling_factor, + d_model=d_model, + nhead=nhead, + dim_feedforward=dim_feedforward, + num_encoder_layers=num_encoder_layers, + num_decoder_layers=num_decoder_layers, + dropout=dropout, + layer_dropout=layer_dropout, + ) + + 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) + + encoder_layer = ConformerEncoderLayer( + d_model, + nhead, + dim_feedforward, + dropout, + layer_dropout, + cnn_module_kernel, + ) + self.encoder = ConformerEncoder(encoder_layer, num_encoder_layers) + + def run_encoder( + self, + x: torch.Tensor, + supervisions: Optional[Supervisions] = None, + warmup: float = 1.0, + ) -> Tuple[torch.Tensor, Optional[torch.Tensor]]: + """ + Args: + x: + The input tensor. Its shape is (batch_size, seq_len, feature_dim). + supervisions: + Supervision in lhotse format. + See https://github.com/lhotse-speech/lhotse/blob/master/lhotse/dataset/speech_recognition.py#L32 # noqa + CAUTION: It contains length information, i.e., start and number of + frames, before subsampling + It is read directly from the batch, without any sorting. It is used + to compute encoder padding mask, which is used as memory key padding + mask for the decoder. + 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: + Tensor: Predictor tensor of dimension (input_length, batch_size, d_model). + Tensor: Mask tensor of dimension (batch_size, input_length) + """ + x = self.encoder_embed(x) + x, pos_emb = self.encoder_pos(x) + x = x.permute(1, 0, 2) # (N, T, C) -> (T, N, C) + mask = encoder_padding_mask(x.size(0), supervisions) + if mask is not None: + mask = mask.to(x.device) + + # Caution: We assume the subsampling factor is 4! + + x = self.encoder( + x, pos_emb, src_key_padding_mask=mask, warmup=warmup + ) # (T, N, C) + + # x = x.permute(1, 0, 2) # (T, N, C) ->(N, T, C) + + # return x, lengths + return x, mask + + +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. + + 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, + ) -> 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) + + 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 + src = src + self.dropout(self.conv_module(src)) + + # 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 + + +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) -> None: + super().__init__() + self.layers = nn.ModuleList( + [copy.deepcopy(encoder_layer) for i in range(num_layers)] + ) + self.num_layers = num_layers + + 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 + + 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, + ) + + return output + + +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) -> None: + """Reset the positional encodings.""" + 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 vecotr 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, `*`). + + Returns: + torch.Tensor: Encoded tensor (batch, time, `*`). + torch.Tensor: Encoded tensor (batch, 2*time-1, `*`). + + """ + self.extend_pe(x) + 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, + ) -> 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. + + 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, + ) + + def rel_shift(self, x: Tensor) -> Tensor: + """Compute relative positional encoding. + + Args: + x: Input tensor (batch, head, time1, 2*time1-1). + time1 means the length of query vector. + + 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 + assert n == 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, time1), + (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, + ) -> 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. + + 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) + p = p.transpose(1, 2) # (batch, head, 2*time1-1, d_k) + + 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.transpose(-2, -1) + ) # (batch, head, time1, 2*time1-1) + matrix_bd = self.rel_shift(matrix_bd) + + 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) + 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). + + """ + + def __init__( + self, channels: int, kernel_size: int, bias: bool = True + ) -> 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.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.depthwise_conv = ScaledConv1d( + channels, + channels, + kernel_size, + stride=1, + padding=(kernel_size - 1) // 2, + 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) -> Tensor: + """Compute convolution module. + + Args: + x: Input tensor (#time, batch, channels). + + Returns: + Tensor: Output tensor (#time, 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 + x = self.depthwise_conv(x) + + x = self.deriv_balancer2(x) + x = self.activation(x) + + x = self.pointwise_conv2(x) # (batch, channel, time) + + return x.permute(2, 0, 1) + + +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, + ) diff --git a/egs/librispeech/ASR/conformer_ctc2/decode.py b/egs/librispeech/ASR/conformer_ctc2/decode.py new file mode 100755 index 000000000..8a4cad1ad --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/decode.py @@ -0,0 +1,996 @@ +#!/usr/bin/env python3 +# Copyright 2021 Xiaomi Corporation (Author: Liyong Guo, +# Fangjun Kuang, +# Quandong Wang) +# +# 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 logging +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 conformer import Conformer + +from icefall.checkpoint import ( + average_checkpoints, + average_checkpoints_with_averaged_model, + find_checkpoints, + load_checkpoint, +) + +from icefall.bpe_graph_compiler import BpeCtcTrainingGraphCompiler +from icefall.decode import ( + get_lattice, + nbest_decoding, + nbest_oracle, + one_best_decoding, + rescore_with_attention_decoder, + rescore_with_n_best_list, + rescore_with_rnn_lm, + rescore_with_whole_lattice, +) +from icefall.env import get_env_info +from icefall.lexicon import Lexicon +from icefall.rnn_lm.model import RnnLmModel +from icefall.utils import ( + AttributeDict, + get_texts, + load_averaged_model, + setup_logger, + store_transcripts, + str2bool, + write_error_stats, +) + + +def get_parser(): + parser = argparse.ArgumentParser( + formatter_class=argparse.ArgumentDefaultsHelpFormatter + ) + + parser.add_argument( + "--epoch", + type=int, + default=77, + 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( + "--method", + type=str, + default="attention-decoder", + help="""Decoding method. + Supported values are: + - (0) ctc-decoding. Use CTC decoding. It uses a sentence piece + model, i.e., lang_dir/bpe.model, to convert word pieces to words. + It needs neither a lexicon nor an n-gram LM. + - (1) ctc-greedy-search. It only use CTC output and a sentence piece + model for decoding. It produces the same results with ctc-decoding. + - (2) 1best. Extract the best path from the decoding lattice as the + decoding result. + - (3) nbest. Extract n paths from the decoding lattice; the path + with the highest score is the decoding result. + - (4) nbest-rescoring. Extract n paths from the decoding lattice, + rescore them with an n-gram LM (e.g., a 4-gram LM), the path with + the highest score is the decoding result. + - (5) whole-lattice-rescoring. Rescore the decoding lattice with an + n-gram LM (e.g., a 4-gram LM), the best path of rescored lattice + is the decoding result. + - (6) attention-decoder. Extract n paths from the LM rescored + lattice, the path with the highest score is the decoding result. + - (7) rnn-lm. Rescoring with attention-decoder and RNN LM. We assume + you have trained an RNN LM using ./rnn_lm/train.py + - (8) nbest-oracle. Its WER is the lower bound of any n-best + rescoring method can achieve. Useful for debugging n-best + rescoring method. + """, + ) + + 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( + "--num-decoder-layers", + type=int, + default=6, + help="""Number of decoder layer of transformer decoder. + Setting this to 0 will not create the decoder at all (pure CTC model) + """, + ) + + parser.add_argument( + "--num-paths", + type=int, + default=100, + help="""Number of paths for n-best based decoding method. + Used only when "method" is one of the following values: + nbest, nbest-rescoring, attention-decoder, rnn-lm, and nbest-oracle + """, + ) + + parser.add_argument( + "--nbest-scale", + type=float, + default=0.5, + help="""The scale to be applied to `lattice.scores`. + It's needed if you use any kinds of n-best based rescoring. + Used only when "method" is one of the following values: + nbest, nbest-rescoring, attention-decoder, rnn-lm, and nbest-oracle + A smaller value results in more unique paths. + """, + ) + + parser.add_argument( + "--exp-dir", + type=str, + default="conformer_ctc2/exp", + help="The experiment dir", + ) + + parser.add_argument( + "--lang-dir", + type=str, + default="data/lang_bpe_500", + help="The lang dir", + ) + + parser.add_argument( + "--lm-dir", + type=str, + default="data/lm", + help="""The n-gram LM dir. + It should contain either G_4_gram.pt or G_4_gram.fst.txt + """, + ) + + parser.add_argument( + "--rnn-lm-exp-dir", + type=str, + default="rnn_lm/exp", + help="""Used only when --method is rnn-lm. + 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 rnn-lm. + It specifies the checkpoint to use. + """, + ) + + parser.add_argument( + "--rnn-lm-avg", + type=int, + default=2, + help="""Used only when --method is rnn-lm. + 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 + """, + ) + + return parser + + +def get_params() -> AttributeDict: + params = AttributeDict( + { + # parameters for conformer + "subsampling_factor": 4, + "feature_dim": 80, + "nhead": 8, + "dim_feedforward": 2048, + "encoder_dim": 512, + "num_encoder_layers": 12, + # parameters for decoding + "search_beam": 20, + "output_beam": 8, + "min_active_states": 30, + "max_active_states": 10000, + "use_double_scores": True, + "env_info": get_env_info(), + } + ) + return params + + +def ctc_greedy_search( + nnet_output: torch.Tensor, + memory: torch.Tensor, + memory_key_padding_mask: torch.Tensor, +) -> List[List[int]]: + """Apply CTC greedy search + + Args: + speech (torch.Tensor): (batch, max_len, feat_dim) + speech_length (torch.Tensor): (batch, ) + Returns: + List[List[int]]: best path result + """ + batch_size = memory.shape[1] + # Let's assume B = batch_size + encoder_out = memory + encoder_mask = memory_key_padding_mask + maxlen = encoder_out.size(0) + + ctc_probs = nnet_output # (B, maxlen, vocab_size) + topk_prob, topk_index = ctc_probs.topk(1, dim=2) # (B, maxlen, 1) + topk_index = topk_index.view(batch_size, maxlen) # (B, maxlen) + topk_index = topk_index.masked_fill_(encoder_mask, 0) # (B, maxlen) + hyps = [hyp.tolist() for hyp in topk_index] + scores = topk_prob.max(1) + hyps = [remove_duplicates_and_blank(hyp) for hyp in hyps] + return hyps, scores + + +def remove_duplicates_and_blank(hyp: List[int]) -> List[int]: + # from https://github.com/wenet-e2e/wenet/blob/main/wenet/utils/common.py + new_hyp: List[int] = [] + cur = 0 + while cur < len(hyp): + if hyp[cur] != 0: + new_hyp.append(hyp[cur]) + prev = cur + while cur < len(hyp) and hyp[cur] == hyp[prev]: + cur += 1 + return new_hyp + + +def decode_one_batch( + params: AttributeDict, + model: nn.Module, + rnn_lm_model: Optional[nn.Module], + HLG: Optional[k2.Fsa], + H: Optional[k2.Fsa], + bpe_model: Optional[spm.SentencePieceProcessor], + batch: dict, + word_table: k2.SymbolTable, + sos_id: int, + eos_id: int, + G: Optional[k2.Fsa] = None, +) -> 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 no rescoring is used, the key is the string `no_rescore`. + If LM rescoring is used, the key is the string `lm_scale_xxx`, + where `xxx` is the value of `lm_scale`. An example key is + `lm_scale_0.7` + - 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`. + + - params.method is "1best", it uses 1best decoding without LM rescoring. + - params.method is "nbest", it uses nbest decoding without LM rescoring. + - params.method is "nbest-rescoring", it uses nbest LM rescoring. + - params.method is "whole-lattice-rescoring", it uses whole lattice LM + rescoring. + + model: + The neural model. + rnn_lm_model: + The neural model for RNN LM. + HLG: + The decoding graph. Used only when params.method is NOT ctc-decoding. + H: + The ctc topo. Used only when params.method is ctc-decoding. + bpe_model: + The BPE model. Used only when params.method is ctc-decoding. + 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. + sos_id: + The token ID of the SOS. + eos_id: + The token ID of the EOS. + G: + An LM. It is not None when params.method is "nbest-rescoring" + or "whole-lattice-rescoring". In general, the G in HLG + is a 3-gram LM, while this G is a 4-gram LM. + Returns: + Return the decoding result. See above description for the format of + the returned dict. Note: If it decodes to nothing, then return None. + """ + if HLG is not None: + device = HLG.device + else: + device = H.device + feature = batch["inputs"] + assert feature.ndim == 3 + feature = feature.to(device) + # at entry, feature is (N, T, C) + + supervisions = batch["supervisions"] + + nnet_output, memory, memory_key_padding_mask = model(feature, supervisions) + # nnet_output is (N, T, C) + + supervision_segments = torch.stack( + ( + supervisions["sequence_idx"], + torch.div( + supervisions["start_frame"], + params.subsampling_factor, + rounding_mode="trunc", + ), + torch.div( + supervisions["num_frames"], + params.subsampling_factor, + rounding_mode="trunc", + ), + ), + 1, + ).to(torch.int32) + + if H is None: + assert HLG is not None + decoding_graph = HLG + else: + assert HLG is None + assert bpe_model is not None + decoding_graph = H + + lattice = get_lattice( + nnet_output=nnet_output, + decoding_graph=decoding_graph, + supervision_segments=supervision_segments, + search_beam=params.search_beam, + output_beam=params.output_beam, + min_active_states=params.min_active_states, + max_active_states=params.max_active_states, + subsampling_factor=params.subsampling_factor, + ) + + if params.method == "ctc-decoding": + best_path = one_best_decoding( + lattice=lattice, use_double_scores=params.use_double_scores + ) + # Note: `best_path.aux_labels` contains token IDs, not word IDs + # since we are using H, not HLG here. + # + # token_ids is a lit-of-list of IDs + token_ids = get_texts(best_path) + + # hyps is a list of str, e.g., ['xxx yyy zzz', ...] + hyps = bpe_model.decode(token_ids) + + # hyps is a list of list of str, e.g., [['xxx', 'yyy', 'zzz'], ... ] + hyps = [s.split() for s in hyps] + key = "ctc-decoding" + return {key: hyps} + + if params.method == "ctc-greedy-search": + hyps, _ = ctc_greedy_search( + nnet_output, + memory, + memory_key_padding_mask, + ) + + # hyps is a list of str, e.g., ['xxx yyy zzz', ...] + hyps = bpe_model.decode(hyps) + + # hyps is a list of list of str, e.g., [['xxx', 'yyy', 'zzz'], ... ] + hyps = [s.split() for s in hyps] + key = "ctc-greedy-search" + return {key: hyps} + + if params.method == "nbest-oracle": + # Note: You can also pass rescored lattices to it. + # We choose the HLG decoded lattice for speed reasons + # as HLG decoding is faster and the oracle WER + # is only slightly worse than that of rescored lattices. + best_path = nbest_oracle( + lattice=lattice, + num_paths=params.num_paths, + ref_texts=supervisions["text"], + word_table=word_table, + nbest_scale=params.nbest_scale, + oov="", + ) + hyps = get_texts(best_path) + hyps = [[word_table[i] for i in ids] for ids in hyps] + key = f"oracle_{params.num_paths}_nbest_scale_{params.nbest_scale}" # noqa + return {key: hyps} + + if params.method in ["1best", "nbest"]: + if params.method == "1best": + best_path = one_best_decoding( + lattice=lattice, use_double_scores=params.use_double_scores + ) + key = "no_rescore" + else: + best_path = nbest_decoding( + lattice=lattice, + num_paths=params.num_paths, + use_double_scores=params.use_double_scores, + nbest_scale=params.nbest_scale, + ) + key = f"no_rescore-nbest-scale-{params.nbest_scale}-{params.num_paths}" # noqa + + hyps = get_texts(best_path) + hyps = [[word_table[i] for i in ids] for ids in hyps] + return {key: hyps} + + assert params.method in [ + "nbest-rescoring", + "whole-lattice-rescoring", + "attention-decoder", + "rnn-lm", + ] + + lm_scale_list = [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7] + lm_scale_list += [0.8, 0.9, 1.0, 1.1, 1.2, 1.3] + lm_scale_list += [1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0] + + if params.method == "nbest-rescoring": + best_path_dict = rescore_with_n_best_list( + lattice=lattice, + G=G, + num_paths=params.num_paths, + lm_scale_list=lm_scale_list, + nbest_scale=params.nbest_scale, + ) + elif params.method == "whole-lattice-rescoring": + best_path_dict = rescore_with_whole_lattice( + lattice=lattice, + G_with_epsilon_loops=G, + lm_scale_list=lm_scale_list, + ) + elif params.method == "attention-decoder": + # lattice uses a 3-gram Lm. We rescore it with a 4-gram LM. + rescored_lattice = rescore_with_whole_lattice( + lattice=lattice, + G_with_epsilon_loops=G, + lm_scale_list=None, + ) + # TODO: pass `lattice` instead of `rescored_lattice` to + # `rescore_with_attention_decoder` + + best_path_dict = rescore_with_attention_decoder( + lattice=rescored_lattice, + num_paths=params.num_paths, + model=model, + memory=memory, + memory_key_padding_mask=memory_key_padding_mask, + sos_id=sos_id, + eos_id=eos_id, + nbest_scale=params.nbest_scale, + ) + elif params.method == "rnn-lm": + # lattice uses a 3-gram Lm. We rescore it with a 4-gram LM. + rescored_lattice = rescore_with_whole_lattice( + lattice=lattice, + G_with_epsilon_loops=G, + lm_scale_list=None, + ) + + best_path_dict = rescore_with_rnn_lm( + lattice=rescored_lattice, + num_paths=params.num_paths, + rnn_lm_model=rnn_lm_model, + model=model, + memory=memory, + memory_key_padding_mask=memory_key_padding_mask, + sos_id=sos_id, + eos_id=eos_id, + blank_id=0, + nbest_scale=params.nbest_scale, + ) + else: + assert False, f"Unsupported decoding method: {params.method}" + + ans = dict() + if best_path_dict is not None: + for lm_scale_str, best_path in best_path_dict.items(): + hyps = get_texts(best_path) + hyps = [[word_table[i] for i in ids] for ids in hyps] + ans[lm_scale_str] = hyps + else: + ans = None + return ans + + +def decode_dataset( + dl: torch.utils.data.DataLoader, + params: AttributeDict, + model: nn.Module, + rnn_lm_model: Optional[nn.Module], + HLG: Optional[k2.Fsa], + H: Optional[k2.Fsa], + bpe_model: Optional[spm.SentencePieceProcessor], + word_table: k2.SymbolTable, + sos_id: int, + eos_id: int, + G: Optional[k2.Fsa] = None, +) -> Dict[str, List[Tuple[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. + rnn_lm_model: + The neural model for RNN LM. + HLG: + The decoding graph. Used only when params.method is NOT ctc-decoding. + H: + The ctc topo. Used only when params.method is ctc-decoding. + bpe_model: + The BPE model. Used only when params.method is ctc-decoding. + word_table: + It is the word symbol table. + sos_id: + The token ID for SOS. + eos_id: + The token ID for EOS. + G: + An LM. It is not None when params.method is "nbest-rescoring" + or "whole-lattice-rescoring". In general, the G in HLG + is a 3-gram LM, while this G is a 4-gram LM. + Returns: + Return a dict, whose key may be "no-rescore" if no LM rescoring + is used, or it may be "lm_scale_0.7" if LM rescoring 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 = "?" + + results = defaultdict(list) + for batch_idx, batch in enumerate(dl): + texts = batch["supervisions"]["text"] + + hyps_dict = decode_one_batch( + params=params, + model=model, + rnn_lm_model=rnn_lm_model, + HLG=HLG, + H=H, + bpe_model=bpe_model, + batch=batch, + word_table=word_table, + G=G, + sos_id=sos_id, + eos_id=eos_id, + ) + + if hyps_dict is not None: + for lm_scale, hyps in hyps_dict.items(): + this_batch = [] + assert len(hyps) == len(texts) + for hyp_words, ref_text in zip(hyps, texts): + ref_words = ref_text.split() + this_batch.append((ref_words, hyp_words)) + + results[lm_scale].extend(this_batch) + else: + assert ( + len(results) > 0 + ), "It should not decode to empty in the first batch!" + this_batch = [] + hyp_words = [] + for ref_text in texts: + ref_words = ref_text.split() + this_batch.append((ref_words, hyp_words)) + + for lm_scale in results.keys(): + results[lm_scale].extend(this_batch) + + num_cuts += len(texts) + + if batch_idx % 100 == 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[List[int], List[int]]]], +): + if params.method in ("attention-decoder", "rnn-lm"): + # Set it to False since there are too many logs. + enable_log = False + else: + enable_log = True + test_set_wers = dict() + for key, results in results_dict.items(): + recog_path = params.exp_dir / f"recogs-{test_set_name}-{key}.txt" + store_transcripts(filename=recog_path, texts=results) + if enable_log: + 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.exp_dir / f"errs-{test_set_name}-{key}.txt" + with open(errs_filename, "w") as f: + wer = write_error_stats( + f, f"{test_set_name}-{key}", results, enable_log=enable_log + ) + test_set_wers[key] = wer + + if enable_log: + 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.exp_dir / f"wer-summary-{test_set_name}.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) + args.lang_dir = Path(args.lang_dir) + args.lm_dir = Path(args.lm_dir) + + params = get_params() + params.update(vars(args)) + + setup_logger(f"{params.exp_dir}/log-{params.method}/log-decode") + logging.info("Decoding started") + logging.info(params) + + lexicon = Lexicon(params.lang_dir) + max_token_id = max(lexicon.tokens) + num_classes = max_token_id + 1 # +1 for the blank + + device = torch.device("cpu") + if torch.cuda.is_available(): + device = torch.device("cuda", 0) + + logging.info(f"device: {device}") + + graph_compiler = BpeCtcTrainingGraphCompiler( + params.lang_dir, + device=device, + sos_token="", + eos_token="", + ) + sos_id = graph_compiler.sos_id + eos_id = graph_compiler.eos_id + + params.num_classes = num_classes + params.sos_id = sos_id + params.eos_id = eos_id + + if params.method == "ctc-decoding" or params.method == "ctc-greedy-search": + HLG = None + H = k2.ctc_topo( + max_token=max_token_id, + modified=False, + device=device, + ) + bpe_model = spm.SentencePieceProcessor() + bpe_model.load(str(params.lang_dir / "bpe.model")) + else: + H = None + bpe_model = None + HLG = k2.Fsa.from_dict( + torch.load(f"{params.lang_dir}/HLG.pt", map_location=device) + ) + assert HLG.requires_grad is False + + if not hasattr(HLG, "lm_scores"): + HLG.lm_scores = HLG.scores.clone() + + if params.method in ( + "nbest-rescoring", + "whole-lattice-rescoring", + "attention-decoder", + "rnn-lm", + ): + if not (params.lm_dir / "G_4_gram.pt").is_file(): + logging.info("Loading G_4_gram.fst.txt") + logging.warning("It may take 8 minutes.") + with open(params.lm_dir / "G_4_gram.fst.txt") as f: + first_word_disambig_id = lexicon.word_table["#0"] + + G = k2.Fsa.from_openfst(f.read(), acceptor=False) + # G.aux_labels is not needed in later computations, so + # remove it here. + del G.aux_labels + # CAUTION: The following line is crucial. + # Arcs entering the back-off state have label equal to #0. + # We have to change it to 0 here. + G.labels[G.labels >= first_word_disambig_id] = 0 + # See https://github.com/k2-fsa/k2/issues/874 + # for why we need to set G.properties to None + G.__dict__["_properties"] = None + G = k2.Fsa.from_fsas([G]).to(device) + G = k2.arc_sort(G) + # Save a dummy value so that it can be loaded in C++. + # See https://github.com/pytorch/pytorch/issues/67902 + # for why we need to do this. + G.dummy = 1 + + torch.save(G.as_dict(), params.lm_dir / "G_4_gram.pt") + else: + logging.info("Loading pre-compiled G_4_gram.pt") + d = torch.load(params.lm_dir / "G_4_gram.pt", map_location=device) + G = k2.Fsa.from_dict(d) + + if params.method in [ + "whole-lattice-rescoring", + "attention-decoder", + "rnn-lm", + ]: + # Add epsilon self-loops to G as we will compose + # it with the whole lattice later + G = k2.add_epsilon_self_loops(G) + G = k2.arc_sort(G) + G = G.to(device) + + # G.lm_scores is used to replace HLG.lm_scores during + # LM rescoring. + G.lm_scores = G.scores.clone() + else: + G = None + + model = Conformer( + num_features=params.feature_dim, + nhead=params.nhead, + d_model=params.encoder_dim, + num_classes=num_classes, + subsampling_factor=params.subsampling_factor, + num_encoder_layers=params.num_encoder_layers, + num_decoder_layers=params.num_decoder_layers, + ) + + 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() + num_param = sum([p.numel() for p in model.parameters()]) + logging.info(f"Number of model parameters: {num_param}") + + rnn_lm_model = None + if params.method == "rnn-lm": + rnn_lm_model = RnnLmModel( + vocab_size=params.num_classes, + 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, + ) + if 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) + else: + rnn_lm_model = load_averaged_model( + params.rnn_lm_exp_dir, + rnn_lm_model, + params.rnn_lm_epoch, + params.rnn_lm_avg, + device, + ) + rnn_lm_model.eval() + + 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, + rnn_lm_model=rnn_lm_model, + HLG=HLG, + H=H, + bpe_model=bpe_model, + word_table=lexicon.word_table, + G=G, + sos_id=sos_id, + eos_id=eos_id, + ) + + save_results( + params=params, test_set_name=test_set, results_dict=results_dict + ) + + logging.info("Done!") + + +torch.set_num_threads(1) +torch.set_num_interop_threads(1) + +if __name__ == "__main__": + main() diff --git a/egs/librispeech/ASR/conformer_ctc2/export.py b/egs/librispeech/ASR/conformer_ctc2/export.py new file mode 100755 index 000000000..584b3c3fc --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/export.py @@ -0,0 +1,281 @@ +#!/usr/bin/env python3 +# +# Copyright 2021 Xiaomi Corporation (Author: Fangjun Kuang, +# Quandong Wang) +# +# 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: +./conformer_ctc2/export.py \ + --exp-dir ./conformer_ctc2/exp \ + --epoch 20 \ + --avg 10 + +It will generate a file exp_dir/pretrained.pt + +To use the generated file with `conformer_ctc2/decode.py`, +you can do: + + cd /path/to/exp_dir + ln -s pretrained.pt epoch-9999.pt + + cd /path/to/egs/librispeech/ASR + ./conformer_ctc2/decode.py \ + --exp-dir ./conformer_ctc2/exp \ + --epoch 9999 \ + --avg 1 \ + --max-duration 100 +""" + +import argparse +import logging +from pathlib import Path + +import torch +from decode import get_params + +from icefall.checkpoint import ( + average_checkpoints, + average_checkpoints_with_averaged_model, + find_checkpoints, + load_checkpoint, +) +from conformer import Conformer + +from icefall.utils import str2bool +from icefall.lexicon import Lexicon + + +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 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( + "--num-decoder-layers", + type=int, + default=6, + help="""Number of decoder layer of transformer decoder. + Setting this to 0 will not create the decoder at all (pure CTC model) + """, + ) + + parser.add_argument( + "--exp-dir", + type=str, + default="conformer_ctc2/exp", + help="""It specifies the directory where all training related + files, e.g., checkpoints, log, etc, are saved + """, + ) + + parser.add_argument( + "--lang-dir", + type=str, + default="data/lang_bpe_500", + help="The lang dir", + ) + + parser.add_argument( + "--jit", + type=str2bool, + default=True, + help="""True to save a model after applying torch.jit.script. + """, + ) + + return parser + + +def main(): + args = get_parser().parse_args() + args.exp_dir = Path(args.exp_dir) + args.lang_dir = Path(args.lang_dir) + + params = get_params() + params.update(vars(args)) + + lexicon = Lexicon(params.lang_dir) + max_token_id = max(lexicon.tokens) + num_classes = max_token_id + 1 # +1 for the blank + + device = torch.device("cpu") + if torch.cuda.is_available(): + device = torch.device("cuda", 0) + + logging.info(f"device: {device}") + + logging.info(params) + + logging.info("About to create model") + + model = Conformer( + num_features=params.feature_dim, + nhead=params.nhead, + d_model=params.encoder_dim, + num_classes=num_classes, + subsampling_factor=params.subsampling_factor, + num_encoder_layers=params.num_encoder_layers, + num_decoder_layers=params.num_decoder_layers, + ) + + model.to(device) + + 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.eval() + + model.to("cpu") + model.eval() + + if params.jit: + 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/conformer_ctc2/label_smoothing.py b/egs/librispeech/ASR/conformer_ctc2/label_smoothing.py new file mode 120000 index 000000000..08734abd7 --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/label_smoothing.py @@ -0,0 +1 @@ +../conformer_ctc/label_smoothing.py \ No newline at end of file diff --git a/egs/librispeech/ASR/conformer_ctc2/optim.py b/egs/librispeech/ASR/conformer_ctc2/optim.py new file mode 120000 index 000000000..e2deb4492 --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/optim.py @@ -0,0 +1 @@ +../pruned_transducer_stateless2/optim.py \ No newline at end of file diff --git a/egs/librispeech/ASR/conformer_ctc2/scaling.py b/egs/librispeech/ASR/conformer_ctc2/scaling.py new file mode 120000 index 000000000..09d802cc4 --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/scaling.py @@ -0,0 +1 @@ +../pruned_transducer_stateless2/scaling.py \ No newline at end of file diff --git a/egs/librispeech/ASR/conformer_ctc2/subsampling.py b/egs/librispeech/ASR/conformer_ctc2/subsampling.py new file mode 100644 index 000000000..3fcb4196f --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/subsampling.py @@ -0,0 +1,121 @@ +#!/usr/bin/env python3 +# Copyright (c) 2021 University of Chinese Academy of Sciences (author: Han Zhu) +# 2022 Xiaomi Corporation (author: Quandong Wang) +# +# 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 +from scaling import ( + ActivationBalancer, + BasicNorm, + DoubleSwish, + ScaledConv2d, + ScaledLinear, +) +from torch import nn + + +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 diff --git a/egs/librispeech/ASR/conformer_ctc2/train.py b/egs/librispeech/ASR/conformer_ctc2/train.py new file mode 100755 index 000000000..d7baa229f --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/train.py @@ -0,0 +1,1119 @@ +#!/usr/bin/env python3 +# Copyright 2021 Xiaomi Corp. (authors: Fangjun Kuang, +# Wei Kang, +# Mingshuang Luo, +# Zengwei Yao, +# Quandong Wang) +# +# 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" + +./conformer_ctc2/train.py \ + --world-size 4 \ + --num-epochs 30 \ + --start-epoch 1 \ + --exp-dir conformer_ctc2/exp \ + --full-libri 1 \ + --max-duration 300 + +# For mix precision training: + +./conformer_ctc2/train.py \ + --world-size 4 \ + --num-epochs 30 \ + --start-epoch 1 \ + --use-fp16 1 \ + --exp-dir conformer_ctc2/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 torch +import torch.multiprocessing as mp +import torch.nn as nn +from asr_datamodule import LibriSpeechAsrDataModule +from conformer import Conformer +from lhotse.cut import Cut +from lhotse.dataset.sampling.base import CutSampler +from lhotse.utils import fix_random_seed +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.bpe_graph_compiler import BpeCtcTrainingGraphCompiler +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.graph_compiler import CtcTrainingGraphCompiler +from icefall.lexicon import Lexicon +from icefall.utils import ( + AttributeDict, + MetricsTracker, + encode_supervisions, + setup_logger, + str2bool, +) + +LRSchedulerType = Union[ + torch.optim.lr_scheduler._LRScheduler, optim.LRScheduler +] + + +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="conformer_ctc2/exp", + help="""The experiment dir. + It specifies the directory where all training related + files, e.g., checkpoints, log, etc, are saved + """, + ) + + parser.add_argument( + "--lang-dir", + type=str, + default="data/lang_bpe_500", + help="""The lang dir + It contains language related input files such as + "lexicon.txt" + """, + ) + + 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( + "--att-rate", + type=float, + default=0.8, + help="""The attention rate. + The total loss is (1 - att_rate) * ctc_loss + att_rate * att_loss + """, + ) + + parser.add_argument( + "--num-decoder-layers", + type=int, + default=6, + help="""Number of decoder layer of transformer decoder. + Setting this to 0 will not create the decoder at all (pure CTC model) + """, + ) + + 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=8000, + 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=20, + 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.", + ) + + 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. + + - beam_size: It is used in k2.ctc_loss + + - reduction: It is used in k2.ctc_loss + + - use_double_scores: It is used in k2.ctc_loss + + - 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": 1, + "reset_interval": 200, + "valid_interval": 3000, # For the 100h subset, use 800 + # parameters for conformer + "feature_dim": 80, + "subsampling_factor": 4, + "encoder_dim": 512, + "nhead": 8, + "dim_feedforward": 2048, + "num_encoder_layers": 12, + # parameters for ctc loss + "beam_size": 10, + "reduction": "sum", + "use_double_scores": True, + # parameters for Noam + "model_warm_step": 3000, # arg given to model, not for lrate + "env_info": get_env_info(), + } + ) + + return params + + +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"] + + if "cur_batch_idx" in saved_params: + params["cur_batch_idx"] = saved_params["cur_batch_idx"] + + 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], + batch: dict, + graph_compiler: BpeCtcTrainingGraphCompiler, + is_training: bool, + warmup: float = 1.0, +) -> Tuple[Tensor, MetricsTracker]: + """ + Compute CTC 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. + graph_compiler: + It is used to build a decoding graph from a ctc topo and training + transcript. The training transcript is contained in the given `batch`, + while the ctc topo is built when this compiler is instantiated. + 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) + + with torch.set_grad_enabled(is_training): + nnet_output, encoder_memory, memory_mask = model( + feature, supervisions, warmup=warmup + ) + # logging.info('feature shape: {}'.format(feature.shape)) + # logging.info('nnet_output shape: {}'.format(nnet_output.shape)) + # logging.info('encoder_memory shape: {}'.format(encoder_memory.shape)) + # logging.info('memory_mask shape: {}'.format(memory_mask.shape)) + # 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. + + # NOTE: We need `encode_supervisions` to sort sequences with + # different duration in decreasing order, required by + # `k2.intersect_dense` called in `k2.ctc_loss` + supervision_segments, texts = encode_supervisions( + supervisions, subsampling_factor=params.subsampling_factor + ) + + if isinstance(graph_compiler, BpeCtcTrainingGraphCompiler): + # Works with a BPE model + token_ids = graph_compiler.texts_to_ids(texts) + decoding_graph = graph_compiler.compile(token_ids) + elif isinstance(graph_compiler, CtcTrainingGraphCompiler): + # Works with a phone lexicon + decoding_graph = graph_compiler.compile(texts) + else: + raise ValueError( + f"Unsupported type of graph compiler: {type(graph_compiler)}" + ) + + dense_fsa_vec = k2.DenseFsaVec( + nnet_output, + supervision_segments, + allow_truncate=params.subsampling_factor - 1, + ) + + ctc_loss = k2.ctc_loss( + decoding_graph=decoding_graph, + dense_fsa_vec=dense_fsa_vec, + output_beam=params.beam_size, + reduction=params.reduction, + use_double_scores=params.use_double_scores, + ) + + if params.att_rate != 0.0: + with torch.set_grad_enabled(is_training): + mmodel = model.module if hasattr(model, "module") else model + # Note: We need to generate an unsorted version of token_ids + # `encode_supervisions()` called above sorts text, but + # encoder_memory and memory_mask are not sorted, so we + # use an unsorted version `supervisions["text"]` to regenerate + # the token_ids + # + # See https://github.com/k2-fsa/icefall/issues/97 + # for more details + unsorted_token_ids = graph_compiler.texts_to_ids( + supervisions["text"] + ) + att_loss = mmodel.decoder_forward( + encoder_memory, + memory_mask, + token_ids=unsorted_token_ids, + sos_id=graph_compiler.sos_id, + eos_id=graph_compiler.eos_id, + ) + loss = (1.0 - params.att_rate) * ctc_loss + params.att_rate * att_loss + else: + loss = ctc_loss + att_loss = torch.tensor([0]) + + assert loss.requires_grad == is_training + + info = MetricsTracker() + with warnings.catch_warnings(): + warnings.simplefilter("ignore") + info["frames"] = ( + (feature_lens // params.subsampling_factor).sum().item() + ) + info["ctc_loss"] = ctc_loss.detach().cpu().item() + if params.att_rate != 0.0: + info["att_loss"] = att_loss.detach().cpu().item() + + # Note: We use reduction=sum while computing the loss. + info["loss"] = loss.detach().cpu().item() + + return loss, info + + +def compute_validation_loss( + params: AttributeDict, + model: Union[nn.Module, DDP], + graph_compiler: BpeCtcTrainingGraphCompiler, + 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, + batch=batch, + graph_compiler=graph_compiler, + 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, + graph_compiler: BpeCtcTrainingGraphCompiler, + scheduler: LRSchedulerType, + 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. + graph_compiler: + It is used to convert transcripts to FSAs. + 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() + + cur_batch_idx = params.get("cur_batch_idx", 0) + + for batch_idx, batch in enumerate(train_dl): + if batch_idx < cur_batch_idx: + continue + cur_batch_idx = batch_idx + + params.batch_idx_train += 1 + batch_size = len(batch["supervisions"]["text"]) + batch_name = batch["supervisions"]["uttid"] + + with torch.cuda.amp.autocast(enabled=params.use_fp16): + loss, loss_info = compute_loss( + params=params, + model=model, + batch=batch, + graph_compiler=graph_compiler, + 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() + + try: + # loss.backward() + scaler.scale(loss).backward() + except RuntimeError as e: + if "CUDA out of memory" in str(e): + logging.error( + f"failing batch size:{batch_size} " + f"failing batch names {batch_name}" + ) + raise + + scheduler.step_batch(params.batch_idx_train) + scaler.step(optimizer) + scaler.update() + optimizer.zero_grad() + + if params.print_diagnostics and batch_idx == 30: + 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 + ): + params.cur_batch_idx = batch_idx + 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, + ) + del params.cur_batch_idx + 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 loss_info["ctc_loss"] == float("inf") or loss_info[ + "att_loss" + ] == float("inf"): + logging.error( + "Your loss contains inf, something goes wrong" + f"failing batch names {batch_name}" + ) + 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, + graph_compiler=graph_compiler, + 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") + logging.info(params) + + if args.tensorboard and rank == 0: + tb_writer = SummaryWriter(log_dir=f"{params.exp_dir}/tensorboard") + else: + tb_writer = None + + lexicon = Lexicon(params.lang_dir) + max_token_id = max(lexicon.tokens) + num_classes = max_token_id + 1 # +1 for the blank + + device = torch.device("cpu") + if torch.cuda.is_available(): + device = torch.device("cuda", rank) + + if "lang_bpe" in str(params.lang_dir): + graph_compiler = BpeCtcTrainingGraphCompiler( + params.lang_dir, + device=device, + sos_token="", + eos_token="", + ) + elif "lang_phone" in str(params.lang_dir): + assert params.att_rate == 0, ( + "Attention decoder training does not support phone lang dirs " + "at this time due to a missing symbol. Set --att-rate=0 " + "for pure CTC training when using a phone-based lang dir." + ) + assert params.num_decoder_layers == 0, ( + "Attention decoder training does not support phone lang dirs " + "at this time due to a missing symbol. " + "Set --num-decoder-layers=0 for pure CTC training when using " + "a phone-based lang dir." + ) + graph_compiler = CtcTrainingGraphCompiler( + lexicon, + device=device, + ) + # Manually add the sos/eos ID with their default values + # from the BPE recipe which we're adapting here. + graph_compiler.sos_id = 1 + graph_compiler.eos_id = 1 + else: + raise ValueError( + f"Unsupported type of lang dir (we expected it to have " + f"'lang_bpe' or 'lang_phone' in its name): {params.lang_dir}" + ) + + logging.info("About to create model") + model = Conformer( + num_features=params.feature_dim, + nhead=params.nhead, + d_model=params.encoder_dim, + num_classes=num_classes, + subsampling_factor=params.subsampling_factor, + num_encoder_layers=params.num_encoder_layers, + num_decoder_layers=params.num_decoder_layers, + ) + + print(model) + + 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: + diagnostic = diagnostics.attach_diagnostics(model) + + librispeech = LibriSpeechAsrDataModule(args) + + train_cuts = librispeech.train_clean_100_cuts() + if params.full_libri: + train_cuts += librispeech.train_clean_360_cuts() + train_cuts += librispeech.train_other_500_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 + return 1.0 <= c.duration <= 20.0 + + def remove_invalid_utt_ctc(c: Cut): + # Caution: We assume the subsampling factor is 4! + # num_tokens = len(sp.encode(c.supervisions[0].text, out_type=int)) + num_tokens = len(graph_compiler.texts_to_ids(c.supervisions[0].text)) + min_output_input_ratio = 0.0005 + max_output_input_ratio = 0.1 + return ( + min_output_input_ratio + < num_tokens / float(c.features.num_frames) + < max_output_input_ratio + ) + + train_cuts = train_cuts.filter(remove_short_and_long_utt) + train_cuts = train_cuts.filter(remove_invalid_utt_ctc) + + 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.print_diagnostics: + scan_pessimistic_batches_for_oom( + model=model, + train_dl=train_dl, + optimizer=optimizer, + graph_compiler=graph_compiler, + params=params, + ) + + 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, + graph_compiler=graph_compiler, + scheduler=scheduler, + 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, + graph_compiler: BpeCtcTrainingGraphCompiler, + params: AttributeDict, +): + 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: + # warmup = 0.0 is so that the derivs for the pruned loss stay zero + # (i.e. are not remembered by the decaying-average in adam), because + # we want to avoid these params being subject to shrinkage in adam. + with torch.cuda.amp.autocast(enabled=params.use_fp16): + loss, _ = compute_loss( + params=params, + model=model, + batch=batch, + graph_compiler=graph_compiler, + is_training=True, + warmup=0.0, + ) + loss.backward() + optimizer.step() + optimizer.zero_grad() + except RuntimeError 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]}) ..." + ) + 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() diff --git a/egs/librispeech/ASR/conformer_ctc2/transformer.py b/egs/librispeech/ASR/conformer_ctc2/transformer.py new file mode 100644 index 000000000..fa179acc0 --- /dev/null +++ b/egs/librispeech/ASR/conformer_ctc2/transformer.py @@ -0,0 +1,1092 @@ +# Copyright 2021 University of Chinese Academy of Sciences (author: Han Zhu) +# Copyright 2022 Xiaomi Corp. (author: Quandong Wang) +# +# 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 +from typing import Dict, List, Optional, Tuple + +import torch +import torch.nn as nn +from label_smoothing import LabelSmoothingLoss +from subsampling import Conv2dSubsampling +from attention import MultiheadAttention +from torch.nn.utils.rnn import pad_sequence + +from scaling import ( + ActivationBalancer, + BasicNorm, + DoubleSwish, + ScaledLinear, + ScaledEmbedding, +) + + +# Note: TorchScript requires Dict/List/etc. to be fully typed. +Supervisions = Dict[str, torch.Tensor] + + +class Transformer(nn.Module): + def __init__( + self, + num_features: int, + num_classes: int, + subsampling_factor: int = 4, + d_model: int = 256, + nhead: int = 4, + dim_feedforward: int = 2048, + num_encoder_layers: int = 12, + num_decoder_layers: int = 6, + dropout: float = 0.1, + layer_dropout: float = 0.075, + ) -> None: + """ + Args: + num_features: + The input dimension of the model. + num_classes: + The output dimension of the model. + subsampling_factor: + Number of output frames is num_in_frames // subsampling_factor. + Currently, subsampling_factor MUST be 4. + d_model: + Attention dimension. + nhead: + Number of heads in multi-head attention. + Must satisfy d_model // nhead == 0. + dim_feedforward: + The output dimension of the feedforward layers in encoder/decoder. + num_encoder_layers: + Number of encoder layers. + num_decoder_layers: + Number of decoder layers. + dropout: + Dropout in encoder/decoder. + layer_dropout (float): layer-dropout rate. + """ + super().__init__() + + self.num_features = num_features + self.num_classes = num_classes + 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_classes) + # 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_classes -> d_model + self.encoder_embed = Conv2dSubsampling(num_features, d_model) + + self.encoder_pos = PositionalEncoding(d_model, dropout) + + encoder_layer = TransformerEncoderLayer( + d_model=d_model, + nhead=nhead, + dim_feedforward=dim_feedforward, + dropout=dropout, + layer_dropout=layer_dropout, + ) + + self.encoder = TransformerEncoder( + encoder_layer=encoder_layer, + num_layers=num_encoder_layers, + ) + + # TODO(fangjun): remove dropout + self.encoder_output_layer = nn.Sequential( + nn.Dropout(p=dropout), ScaledLinear(d_model, num_classes, bias=True) + ) + + if num_decoder_layers > 0: + self.decoder_num_class = ( + self.num_classes + ) # bpe model already has sos/eos symbol + + self.decoder_embed = ScaledEmbedding( + num_embeddings=self.decoder_num_class, embedding_dim=d_model + ) + self.decoder_pos = PositionalEncoding(d_model, dropout) + + decoder_layer = TransformerDecoderLayer( + d_model=d_model, + nhead=nhead, + dim_feedforward=dim_feedforward, + dropout=dropout, + ) + + self.decoder = TransformerDecoder( + decoder_layer=decoder_layer, + num_layers=num_decoder_layers, + ) + + self.decoder_output_layer = ScaledLinear( + d_model, self.decoder_num_class, bias=True + ) + + self.decoder_criterion = LabelSmoothingLoss() + else: + self.decoder_criterion = None + + def forward( + self, + x: torch.Tensor, + supervision: Optional[Supervisions] = None, + warmup: float = 1.0, + ) -> Tuple[torch.Tensor, torch.Tensor, Optional[torch.Tensor]]: + """ + Args: + x: + The input tensor. Its shape is (N, T, C). + supervision: + Supervision in lhotse format. + See https://github.com/lhotse-speech/lhotse/blob/master/lhotse/dataset/speech_recognition.py#L32 # noqa + (CAUTION: It contains length information, i.e., start and number of + frames, before subsampling) + 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 3 tensors: + - CTC output for ctc decoding. Its shape is (N, T, C) + - Encoder output with shape (T, N, C). It can be used as key and + value for the decoder. + - Encoder output padding mask. It can be used as + memory_key_padding_mask for the decoder. Its shape is (N, T). + It is None if `supervision` is None. + """ + + encoder_memory, memory_key_padding_mask = self.run_encoder( + x, supervision, warmup + ) + + x = self.ctc_output(encoder_memory) + return x, encoder_memory, memory_key_padding_mask + + def run_encoder( + self, + x: torch.Tensor, + supervisions: Optional[Supervisions] = None, + warmup: float = 1.0, + ) -> Tuple[torch.Tensor, Optional[torch.Tensor]]: + """Run the transformer encoder. + + Args: + x: + The model input. Its shape is (N, T, C). + supervisions: + Supervision in lhotse format. + See https://github.com/lhotse-speech/lhotse/blob/master/lhotse/dataset/speech_recognition.py#L32 # noqa + CAUTION: It contains length information, i.e., start and number of + frames, before subsampling + It is read directly from the batch, without any sorting. It is used + to compute the encoder padding mask, which is used as memory key + padding mask for the decoder. + Returns: + Return a tuple with two tensors: + - The encoder output, with shape (T, N, C) + - encoder padding mask, with shape (N, T). + The mask is None if `supervisions` is None. + It is used as memory key padding mask in the decoder. + """ + x = self.encoder_embed(x) + x = self.encoder_pos(x) + x = x.permute(1, 0, 2) # (N, T, C) -> (T, N, C) + mask = encoder_padding_mask(x.size(0), supervisions) + mask = mask.to(x.device) if mask is not None else None + x = self.encoder( + x, src_key_padding_mask=mask, warmup=warmup + ) # (T, N, C) + + return x, mask + + def ctc_output(self, x: torch.Tensor) -> torch.Tensor: + """ + Args: + x: + The output tensor from the transformer encoder. + Its shape is (T, N, C) + + Returns: + Return a tensor that can be used for CTC decoding. + Its shape is (N, T, C) + """ + x = self.encoder_output_layer(x) + x = x.permute(1, 0, 2) # (T, N, C) ->(N, T, C) + x = nn.functional.log_softmax(x, dim=-1) # (N, T, C) + return x + + @torch.jit.export + def decoder_forward( + self, + memory: torch.Tensor, + memory_key_padding_mask: torch.Tensor, + token_ids: List[List[int]], + sos_id: int, + eos_id: int, + ) -> torch.Tensor: + """ + Args: + memory: + It's the output of the encoder with shape (T, N, C) + memory_key_padding_mask: + The padding mask from the encoder. + token_ids: + A list-of-list IDs. Each sublist contains IDs for an utterance. + The IDs can be either phone IDs or word piece IDs. + sos_id: + sos token id + eos_id: + eos token id + + Returns: + A scalar, the **sum** of label smoothing loss over utterances + in the batch without any normalization. + """ + ys_in = add_sos(token_ids, sos_id=sos_id) + ys_in = [torch.tensor(y) for y in ys_in] + ys_in_pad = pad_sequence( + ys_in, batch_first=True, padding_value=float(eos_id) + ) + + ys_out = add_eos(token_ids, eos_id=eos_id) + ys_out = [torch.tensor(y) for y in ys_out] + ys_out_pad = pad_sequence( + ys_out, batch_first=True, padding_value=float(-1) + ) + + device = memory.device + ys_in_pad = ys_in_pad.to(device) + ys_out_pad = ys_out_pad.to(device) + + tgt_mask = generate_square_subsequent_mask(ys_in_pad.shape[-1]).to( + device + ) + + tgt_key_padding_mask = decoder_padding_mask(ys_in_pad, ignore_id=eos_id) + # TODO: Use length information to create the decoder padding mask + # We set the first column to False since the first column in ys_in_pad + # contains sos_id, which is the same as eos_id in our current setting. + tgt_key_padding_mask[:, 0] = False + + tgt = self.decoder_embed(ys_in_pad) # (N, T) -> (N, T, C) + tgt = self.decoder_pos(tgt) + tgt = tgt.permute(1, 0, 2) # (N, T, C) -> (T, N, C) + pred_pad = self.decoder( + tgt=tgt, + memory=memory, + tgt_mask=tgt_mask, + tgt_key_padding_mask=tgt_key_padding_mask, + memory_key_padding_mask=memory_key_padding_mask, + ) # (T, N, C) + pred_pad = pred_pad.permute(1, 0, 2) # (T, N, C) -> (N, T, C) + pred_pad = self.decoder_output_layer(pred_pad) # (N, T, C) + + decoder_loss = self.decoder_criterion(pred_pad, ys_out_pad) + + return decoder_loss + + @torch.jit.export + def decoder_nll( + self, + memory: torch.Tensor, + memory_key_padding_mask: torch.Tensor, + token_ids: List[torch.Tensor], + sos_id: int, + eos_id: int, + ) -> torch.Tensor: + """ + Args: + memory: + It's the output of the encoder with shape (T, N, C) + memory_key_padding_mask: + The padding mask from the encoder. + token_ids: + A list-of-list IDs (e.g., word piece IDs). + Each sublist represents an utterance. + sos_id: + The token ID for SOS. + eos_id: + The token ID for EOS. + Returns: + A 2-D tensor of shape (len(token_ids), max_token_length) + representing the cross entropy loss (i.e., negative log-likelihood). + """ + # The common part between this function and decoder_forward could be + # extracted as a separate function. + if isinstance(token_ids[0], torch.Tensor): + # This branch is executed by torchscript in C++. + # See https://github.com/k2-fsa/k2/pull/870 + # https://github.com/k2-fsa/k2/blob/3c1c18400060415b141ccea0115fd4bf0ad6234e/k2/torch/bin/attention_rescore.cu#L286 + token_ids = [tolist(t) for t in token_ids] + + ys_in = add_sos(token_ids, sos_id=sos_id) + ys_in = [torch.tensor(y) for y in ys_in] + ys_in_pad = pad_sequence( + ys_in, batch_first=True, padding_value=float(eos_id) + ) + + ys_out = add_eos(token_ids, eos_id=eos_id) + ys_out = [torch.tensor(y) for y in ys_out] + ys_out_pad = pad_sequence( + ys_out, batch_first=True, padding_value=float(-1) + ) + + device = memory.device + ys_in_pad = ys_in_pad.to(device, dtype=torch.int64) + ys_out_pad = ys_out_pad.to(device, dtype=torch.int64) + + tgt_mask = generate_square_subsequent_mask(ys_in_pad.shape[-1]).to( + device + ) + + tgt_key_padding_mask = decoder_padding_mask(ys_in_pad, ignore_id=eos_id) + # TODO: Use length information to create the decoder padding mask + # We set the first column to False since the first column in ys_in_pad + # contains sos_id, which is the same as eos_id in our current setting. + tgt_key_padding_mask[:, 0] = False + + tgt = self.decoder_embed(ys_in_pad) # (B, T) -> (B, T, F) + tgt = self.decoder_pos(tgt) + tgt = tgt.permute(1, 0, 2) # (B, T, F) -> (T, B, F) + pred_pad = self.decoder( + tgt=tgt, + memory=memory, + tgt_mask=tgt_mask, + tgt_key_padding_mask=tgt_key_padding_mask, + memory_key_padding_mask=memory_key_padding_mask, + ) # (T, B, F) + pred_pad = pred_pad.permute(1, 0, 2) # (T, B, F) -> (B, T, F) + pred_pad = self.decoder_output_layer(pred_pad) # (B, T, F) + # nll: negative log-likelihood + nll = torch.nn.functional.cross_entropy( + pred_pad.view(-1, self.decoder_num_class), + ys_out_pad.view(-1), + ignore_index=-1, + reduction="none", + ) + + nll = nll.view(pred_pad.shape[0], -1) + + return nll + + +class TransformerEncoderLayer(nn.Module): + """ + Modified from torch.nn.TransformerEncoderLayer. + + 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). + activation: + the activation function of intermediate layer, relu or + gelu (default=relu). + + Examples:: + >>> encoder_layer = TransformerEncoderLayer(d_model=512, nhead=8) + >>> src = torch.rand(10, 32, 512) + >>> out = encoder_layer(src) + """ + + def __init__( + self, + d_model: int, + nhead: int, + dim_feedforward: int = 2048, + dropout: float = 0.1, + layer_dropout: float = 0.075, + activation: str = "relu", + ) -> None: + super(TransformerEncoderLayer, self).__init__() + + self.layer_dropout = layer_dropout + + self.self_attn = MultiheadAttention(d_model, nhead, dropout=0.0) + # Implementation of Feedforward model + + 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.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 __setstate__(self, state): + # if "activation" not in state: + # state["activation"] = nn.functional.relu + # super(TransformerEncoderLayer, self).__setstate__(state) + + def forward( + self, + src: torch.Tensor, + src_mask: Optional[torch.Tensor] = None, + src_key_padding_mask: Optional[torch.Tensor] = None, + warmup: float = 1.0, + ) -> torch.Tensor: + """ + Pass the input through the encoder layer. + + Args: + src: the sequence to the encoder layer (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). + src_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 + """ + 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 + + # src_att = self.self_attn(src, src, src, src_mask) + src_att = self.self_attn( + src, + src, + src, + attn_mask=src_mask, + key_padding_mask=src_key_padding_mask, + )[0] + src = src + self.dropout(src_att) + + 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 + + +class TransformerDecoderLayer(nn.Module): + """ + Modified from torch.nn.TransformerDecoderLayer. + Add support of normalize_before, + i.e., use layer_norm before the first block. + + 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). + activation: + the activation function of intermediate layer, relu or + gelu (default=relu). + + Examples:: + >>> decoder_layer = nn.TransformerDecoderLayer(d_model=512, nhead=8) + >>> memory = torch.rand(10, 32, 512) + >>> tgt = torch.rand(20, 32, 512) + >>> out = decoder_layer(tgt, memory) + """ + + def __init__( + self, + d_model: int, + nhead: int, + dim_feedforward: int = 2048, + dropout: float = 0.1, + layer_dropout: float = 0.075, + # activation: str = "relu", + normalize_before: bool = True, + ) -> None: + super(TransformerDecoderLayer, self).__init__() + self.layer_dropout = layer_dropout + self.self_attn = MultiheadAttention(d_model, nhead, dropout=0.0) + self.src_attn = MultiheadAttention(d_model, nhead, dropout=0.0) + # Implementation of Feedforward model + 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.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 __setstate__(self, state): + # if "activation" not in state: + # state["activation"] = nn.functional.relu + # super(TransformerDecoderLayer, self).__setstate__(state) + + def forward( + self, + tgt: torch.Tensor, + memory: torch.Tensor, + tgt_mask: Optional[torch.Tensor] = None, + memory_mask: Optional[torch.Tensor] = None, + tgt_key_padding_mask: Optional[torch.Tensor] = None, + memory_key_padding_mask: Optional[torch.Tensor] = None, + warmup: float = 1.0, + ) -> torch.Tensor: + """Pass the inputs (and mask) through the decoder layer. + + Args: + tgt: + the sequence to the decoder layer (required). + memory: + the sequence from the last layer of the encoder (required). + tgt_mask: + the mask for the tgt sequence (optional). + memory_mask: + the mask for the memory sequence (optional). + tgt_key_padding_mask: + the mask for the tgt keys per batch (optional). + memory_key_padding_mask: + the mask for the memory keys per batch (optional). + warmup: controls selective bypass of of layers; if < 1.0, we will + bypass layers more frequently. + + + + Shape: + tgt: (T, N, E). + memory: (S, N, E). + tgt_mask: (T, T). + memory_mask: (T, S). + tgt_key_padding_mask: (N, T). + memory_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 + """ + tgt_orig = tgt + + 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 + + # tgt_att = self.self_attn(tgt, tgt, tgt, tgt_mask) + tgt_att = self.self_attn( + tgt, + tgt, + tgt, + attn_mask=tgt_mask, + key_padding_mask=tgt_key_padding_mask, + )[0] + tgt = tgt + self.dropout(tgt_att) + + # src_att = self.src_attn(tgt, memory, memory, memory_mask) + src_att = self.src_attn( + tgt, + memory, + memory, + attn_mask=memory_mask, + key_padding_mask=memory_key_padding_mask, + )[0] + tgt = tgt + self.dropout(src_att) + + tgt = tgt + self.dropout(self.feed_forward(tgt)) + + tgt = self.norm_final(self.balancer(tgt)) + + if alpha != 1.0: + tgt = alpha * tgt + (1 - alpha) * tgt_orig + + return tgt + + +def _get_activation_fn(activation: str): + if activation == "relu": + return nn.functional.relu + elif activation == "gelu": + return nn.functional.gelu + + raise RuntimeError( + "activation should be relu/gelu, not {}".format(activation) + ) + + +class TransformerEncoder(nn.Module): + r"""TransformerEncoder is a stack of N encoder layers + + Args: + encoder_layer: an instance of the TransformerEncoderLayer() class (required). + num_layers: the number of sub-encoder-layers in the encoder (required). + + Examples:: + >>> encoder_layer = TransformerEncoderLayer(d_model=512, nhead=8) + >>> transformer_encoder = TransformerEncoder(encoder_layer, num_layers=6) + >>> src = torch.rand(10, 32, 512) + >>> out = transformer_encoder(src) + """ + + def __init__(self, encoder_layer: nn.Module, num_layers: int) -> None: + super().__init__() + self.layers = nn.ModuleList( + [copy.deepcopy(encoder_layer) for i in range(num_layers)] + ) + self.num_layers = num_layers + + def forward( + self, + src: torch.Tensor, + mask: Optional[torch.Tensor] = None, + src_key_padding_mask: Optional[torch.Tensor] = None, + warmup: float = 1.0, + ) -> torch.Tensor: + r"""Pass the input through the encoder layers in turn. + + Args: + src: the sequence to the encoder (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). + 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 + + for i, mod in enumerate(self.layers): + output = mod( + output, + src_mask=mask, + src_key_padding_mask=src_key_padding_mask, + warmup=warmup, + ) + + return output + + +class TransformerDecoder(nn.Module): + r"""TransformerDecoder is a stack of N decoder layers + + Args: + decoder_layer: an instance of the TransformerDecoderLayer() class (required). + num_layers: the number of sub-decoder-layers in the decoder (required). + + Examples:: + >>> decoder_layer = TransformerDecoderLayer(d_model=512, nhead=8) + >>> transformer_decoder = TransformerDecoder(decoder_layer, num_layers=6) + >>> memory = torch.rand(10, 32, 512) + >>> tgt = torch.rand(10, 32, 512) + >>> out = transformer_decoder(tgt, memory) + """ + + def __init__(self, decoder_layer: nn.Module, num_layers: int) -> None: + super().__init__() + self.layers = nn.ModuleList( + [copy.deepcopy(decoder_layer) for i in range(num_layers)] + ) + self.num_layers = num_layers + + def forward( + self, + tgt: torch.Tensor, + memory: torch.Tensor, + tgt_mask: Optional[torch.Tensor] = None, + memory_mask: Optional[torch.Tensor] = None, + tgt_key_padding_mask: Optional[torch.Tensor] = None, + memory_key_padding_mask: Optional[torch.Tensor] = None, + warmup: float = 1.0, + ) -> torch.Tensor: + r"""Pass the input through the decoder layers in turn. + + Args: + tgt: the sequence to the decoder (required). + memory: the sequence from the last layer of the encoder (required). + tgt_mask: the mask for the tgt sequence (optional). + memory_mask: the mask for the memory sequence (optional). + tgt_key_padding_mask: the mask for the tgt keys per batch (optional). + memory_key_padding_mask: the mask for the memory keys per batch (optional). + + Shape: + tgt: (S, N, E). + tgt_mask: (S, S). + tgt_key_padding_mask: (N, S). + + """ + output = tgt + + for i, mod in enumerate(self.layers): + output = mod( + output, + memory, + tgt_mask=tgt_mask, + memory_mask=memory_mask, + tgt_key_padding_mask=tgt_key_padding_mask, + memory_key_padding_mask=memory_key_padding_mask, + warmup=warmup, + ) + + return output + + +class PositionalEncoding(nn.Module): + """This class implements the positional encoding + proposed in the following paper: + + - Attention Is All You Need: https://arxiv.org/pdf/1706.03762.pdf + + PE(pos, 2i) = sin(pos / (10000^(2i/d_modle)) + PE(pos, 2i+1) = cos(pos / (10000^(2i/d_modle)) + + Note:: + + 1 / (10000^(2i/d_model)) = exp(-log(10000^(2i/d_model))) + = exp(-1* 2i / d_model * log(100000)) + = exp(2i * -(log(10000) / d_model)) + """ + + def __init__(self, d_model: int, dropout: float = 0.1) -> None: + """ + Args: + d_model: + Embedding dimension. + dropout: + Dropout probability to be applied to the output of this module. + """ + super().__init__() + self.d_model = d_model + self.xscale = math.sqrt(self.d_model) + self.dropout = nn.Dropout(p=dropout) + # not doing: self.pe = None because of errors thrown by torchscript + self.pe = torch.zeros(1, 0, self.d_model, dtype=torch.float32) + + def extend_pe(self, x: torch.Tensor) -> None: + """Extend the time t in the positional encoding if required. + + The shape of `self.pe` is (1, T1, d_model). The shape of the input x + is (N, T, d_model). If T > T1, then we change the shape of self.pe + to (N, T, d_model). Otherwise, nothing is done. + + Args: + x: + It is a tensor of shape (N, T, C). + Returns: + Return None. + """ + if self.pe is not None: + if self.pe.size(1) >= x.size(1): + self.pe = self.pe.to(dtype=x.dtype, device=x.device) + return + pe = torch.zeros(x.size(1), self.d_model, dtype=torch.float32) + position = torch.arange(0, x.size(1), dtype=torch.float32).unsqueeze(1) + div_term = torch.exp( + torch.arange(0, self.d_model, 2, dtype=torch.float32) + * -(math.log(10000.0) / self.d_model) + ) + pe[:, 0::2] = torch.sin(position * div_term) + pe[:, 1::2] = torch.cos(position * div_term) + pe = pe.unsqueeze(0) + # Now pe is of shape (1, T, d_model), where T is x.size(1) + self.pe = pe.to(device=x.device, dtype=x.dtype) + + def forward(self, x: torch.Tensor) -> torch.Tensor: + """ + Add positional encoding. + + Args: + x: + Its shape is (N, T, C) + + Returns: + Return a tensor of shape (N, T, C) + """ + self.extend_pe(x) + x = x * self.xscale + self.pe[:, : x.size(1), :] + return self.dropout(x) + + +class Noam(object): + """ + Implements Noam optimizer. + + Proposed in + "Attention Is All You Need", https://arxiv.org/pdf/1706.03762.pdf + + Modified from + https://github.com/espnet/espnet/blob/master/espnet/nets/pytorch_backend/transformer/optimizer.py # noqa + + Args: + params: + iterable of parameters to optimize or dicts defining parameter groups + model_size: + attention dimension of the transformer model + factor: + learning rate factor + warm_step: + warmup steps + """ + + def __init__( + self, + params, + model_size: int = 256, + factor: float = 10.0, + warm_step: int = 25000, + weight_decay=0, + ) -> None: + """Construct an Noam object.""" + self.optimizer = torch.optim.Adam( + params, lr=0, betas=(0.9, 0.98), eps=1e-9, weight_decay=weight_decay + ) + self._step = 0 + self.warmup = warm_step + self.factor = factor + self.model_size = model_size + self._rate = 0 + + @property + def param_groups(self): + """Return param_groups.""" + return self.optimizer.param_groups + + def step(self): + """Update parameters and rate.""" + self._step += 1 + rate = self.rate() + for p in self.optimizer.param_groups: + p["lr"] = rate + self._rate = rate + self.optimizer.step() + + def rate(self, step=None): + """Implement `lrate` above.""" + if step is None: + step = self._step + return ( + self.factor + * self.model_size ** (-0.5) + * min(step ** (-0.5), step * self.warmup ** (-1.5)) + ) + + def zero_grad(self): + """Reset gradient.""" + self.optimizer.zero_grad() + + def state_dict(self): + """Return state_dict.""" + return { + "_step": self._step, + "warmup": self.warmup, + "factor": self.factor, + "model_size": self.model_size, + "_rate": self._rate, + "optimizer": self.optimizer.state_dict(), + } + + def load_state_dict(self, state_dict): + """Load state_dict.""" + for key, value in state_dict.items(): + if key == "optimizer": + self.optimizer.load_state_dict(state_dict["optimizer"]) + else: + setattr(self, key, value) + + +def encoder_padding_mask( + max_len: int, supervisions: Optional[Supervisions] = None +) -> Optional[torch.Tensor]: + """Make mask tensor containing indexes of padded part. + + TODO:: + This function **assumes** that the model uses + a subsampling factor of 4. We should remove that + assumption later. + + Args: + max_len: + Maximum length of input features. + CAUTION: It is the length after subsampling. + supervisions: + Supervision in lhotse format. + See https://github.com/lhotse-speech/lhotse/blob/master/lhotse/dataset/speech_recognition.py#L32 # noqa + (CAUTION: It contains length information, i.e., start and number of + frames, before subsampling) + + Returns: + Tensor: Mask tensor of dimension (batch_size, input_length), + True denote the masked indices. + """ + if supervisions is None: + return None + + supervision_segments = torch.stack( + ( + supervisions["sequence_idx"], + supervisions["start_frame"], + supervisions["num_frames"], + ), + 1, + ).to(torch.int32) + + lengths = [ + 0 for _ in range(int(supervision_segments[:, 0].max().item()) + 1) + ] + for idx in range(supervision_segments.size(0)): + # Note: TorchScript doesn't allow to unpack tensors as tuples + sequence_idx = supervision_segments[idx, 0].item() + start_frame = supervision_segments[idx, 1].item() + num_frames = supervision_segments[idx, 2].item() + lengths[sequence_idx] = start_frame + num_frames + + lengths = [((i - 1) // 2 - 1) // 2 for i in lengths] + bs = int(len(lengths)) + seq_range = torch.arange(0, max_len, dtype=torch.int64) + seq_range_expand = seq_range.unsqueeze(0).expand(bs, max_len) + # Note: TorchScript doesn't implement Tensor.new() + seq_length_expand = torch.tensor( + lengths, device=seq_range_expand.device, dtype=seq_range_expand.dtype + ).unsqueeze(-1) + mask = seq_range_expand >= seq_length_expand + + return mask + + +def decoder_padding_mask( + ys_pad: torch.Tensor, ignore_id: int = -1 +) -> torch.Tensor: + """Generate a length mask for input. + + The masked position are filled with True, + Unmasked positions are filled with False. + + Args: + ys_pad: + padded tensor of dimension (batch_size, input_length). + ignore_id: + the ignored number (the padding number) in ys_pad + + Returns: + Tensor: + a bool tensor of the same shape as the input tensor. + """ + ys_mask = ys_pad == ignore_id + return ys_mask + + +def generate_square_subsequent_mask(sz: int) -> torch.Tensor: + """Generate a square mask for the sequence. The masked positions are + filled with float('-inf'). Unmasked positions are filled with float(0.0). + The mask can be used for masked self-attention. + + For instance, if sz is 3, it returns:: + + tensor([[0., -inf, -inf], + [0., 0., -inf], + [0., 0., 0]]) + + Args: + sz: mask size + + Returns: + A square mask of dimension (sz, sz) + """ + mask = (torch.triu(torch.ones(sz, sz)) == 1).transpose(0, 1) + mask = ( + mask.float() + .masked_fill(mask == 0, float("-inf")) + .masked_fill(mask == 1, float(0.0)) + ) + return mask + + +def add_sos(token_ids: List[List[int]], sos_id: int) -> List[List[int]]: + """Prepend sos_id to each utterance. + + Args: + token_ids: + A list-of-list of token IDs. Each sublist contains + token IDs (e.g., word piece IDs) of an utterance. + sos_id: + The ID of the SOS token. + + Return: + Return a new list-of-list, where each sublist starts + with SOS ID. + """ + return [[sos_id] + utt for utt in token_ids] + + +def add_eos(token_ids: List[List[int]], eos_id: int) -> List[List[int]]: + """Append eos_id to each utterance. + + Args: + token_ids: + A list-of-list of token IDs. Each sublist contains + token IDs (e.g., word piece IDs) of an utterance. + eos_id: + The ID of the EOS token. + + Return: + Return a new list-of-list, where each sublist ends + with EOS ID. + """ + return [utt + [eos_id] for utt in token_ids] + + +def tolist(t: torch.Tensor) -> List[int]: + """Used by jit""" + return torch.jit.annotate(List[int], t.tolist()) diff --git a/egs/librispeech/ASR/pruned_transducer_stateless2/scaling.py b/egs/librispeech/ASR/pruned_transducer_stateless2/scaling.py index c190be626..26a8cca44 100644 --- a/egs/librispeech/ASR/pruned_transducer_stateless2/scaling.py +++ b/egs/librispeech/ASR/pruned_transducer_stateless2/scaling.py @@ -643,7 +643,8 @@ class ScaledEmbedding(nn.Module): ) def extra_repr(self) -> str: - s = "{num_embeddings}, {embedding_dim}, scale={scale}" + # 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: