File size: 19,694 Bytes
c578da5
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
---
tasks:
- auto-speech-recognition
domain:
- audio
model-type:
- Non-autoregressive
frameworks:
- pytorch
backbone:
- transformer/conformer
metrics:
- CER
license: Apache License 2.0
language: 
- cn
tags:
- FunASR
- Paraformer
- Alibaba
- INTERSPEECH 2022
datasets:
  train:
  - 60,000 hour industrial Mandarin task
  test:
  - AISHELL-1 dev/test
  - AISHELL-2 dev_android/dev_ios/dev_mic/test_android/test_ios/test_mic
  - WentSpeech dev/test_meeting/test_net
  - SpeechIO TIOBE
  - 60,000 hour industrial Mandarin task
indexing:
   results:
   - task:
       name: Automatic Speech Recognition
     dataset:
       name: 60,000 hour industrial Mandarin task
       type: audio    # optional
       args: 16k sampling rate, 8404 characters  # optional
     metrics:
       - type: CER
         value: 8.53%  # float
         description: greedy search, withou lm, avg.
         args: default
       - type: RTF
         value: 0.0251  # float
         description: GPU inference on V100
         args: batch_size=1
widgets:
  - task: auto-speech-recognition
    model_revision: v2.0.4
    inputs:
      - type: audio
        name: input
        title: 音频
    examples:
      - name: 1
        title: 示例1
        inputs:
          - name: input
            data: git://example/asr_example.wav
    inferencespec:
      cpu: 8 #CPU数量
      memory: 4096
finetune-support: True
---


# Highlights
- Paraformer-large长音频模型集成VAD、ASR、标点与时间戳功能,可直接对时长为数小时音频进行识别,并输出带标点文字与时间戳:
  - ASR模型:[Parformer-large模型](https://www.modelscope.cn/models/damo/speech_paraformer-large_asr_nat-zh-cn-16k-common-vocab8404-pytorch/summary)结构为非自回归语音识别模型,多个中文公开数据集上取得SOTA效果,可快速地基于ModelScope对模型进行微调定制和推理。
  - 热词版本:[Paraformer-large热词版模型](https://www.modelscope.cn/models/damo/speech_paraformer-large-contextual_asr_nat-zh-cn-16k-common-vocab8404/summary)支持热词定制功能,基于提供的热词列表进行激励增强,提升热词的召回率和准确率。


## <strong>[FunASR开源项目介绍](https://github.com/alibaba-damo-academy/FunASR)</strong>
<strong>[FunASR](https://github.com/alibaba-damo-academy/FunASR)</strong>希望在语音识别的学术研究和工业应用之间架起一座桥梁。通过发布工业级语音识别模型的训练和微调,研究人员和开发人员可以更方便地进行语音识别模型的研究和生产,并推动语音识别生态的发展。让语音识别更有趣!

[**github仓库**](https://github.com/alibaba-damo-academy/FunASR)
| [**最新动态**](https://github.com/alibaba-damo-academy/FunASR#whats-new) 
| [**环境安装**](https://github.com/alibaba-damo-academy/FunASR#installation)
| [**服务部署**](https://www.funasr.com)
| [**模型库**](https://github.com/alibaba-damo-academy/FunASR/tree/main/model_zoo)
| [**联系我们**](https://github.com/alibaba-damo-academy/FunASR#contact)


## 模型原理介绍

Paraformer是达摩院语音团队提出的一种高效的非自回归端到端语音识别框架。本项目为Paraformer中文通用语音识别模型,采用工业级数万小时的标注音频进行模型训练,保证了模型的通用识别效果。模型可以被应用于语音输入法、语音导航、智能会议纪要等场景。

<p align="center">
<img src="fig/struct.png" alt="Paraformer模型结构"  width="500" />


Paraformer模型结构如上图所示,由 Encoder、Predictor、Sampler、Decoder 与 Loss function 五部分组成。Encoder可以采用不同的网络结构,例如self-attention,conformer,SAN-M等。Predictor 为两层FFN,预测目标文字个数以及抽取目标文字对应的声学向量。Sampler 为无可学习参数模块,依据输入的声学向量和目标向量,生产含有语义的特征向量。Decoder 结构与自回归模型类似,为双向建模(自回归为单向建模)。Loss function 部分,除了交叉熵(CE)与 MWER 区分性优化目标,还包括了 Predictor 优化目标 MAE。


其核心点主要有:  
- Predictor 模块:基于 Continuous integrate-and-fire (CIF) 的 预测器 (Predictor) 来抽取目标文字对应的声学特征向量,可以更加准确的预测语音中目标文字个数。  
- Sampler:通过采样,将声学特征向量与目标文字向量变换成含有语义信息的特征向量,配合双向的 Decoder 来增强模型对于上下文的建模能力。  
- 基于负样本采样的 MWER 训练准则。  

更详细的细节见:
- 论文: [Paraformer: Fast and Accurate Parallel Transformer for Non-autoregressive End-to-End Speech Recognition](https://arxiv.org/abs/2206.08317)
- 论文解读:[Paraformer: 高识别率、高计算效率的单轮非自回归端到端语音识别模型](https://mp.weixin.qq.com/s/xQ87isj5_wxWiQs4qUXtVw)



#### 基于ModelScope进行推理

- 推理支持音频格式如下:
  - wav文件路径,例如:data/test/audios/asr_example.wav
  - pcm文件路径,例如:data/test/audios/asr_example.pcm
  - wav文件url,例如:https://isv-data.oss-cn-hangzhou.aliyuncs.com/ics/MaaS/ASR/test_audio/asr_example_zh.wav
  - wav二进制数据,格式bytes,例如:用户直接从文件里读出bytes数据或者是麦克风录出bytes数据。
  - 已解析的audio音频,例如:audio, rate = soundfile.read("asr_example_zh.wav"),类型为numpy.ndarray或者torch.Tensor。
  - wav.scp文件,需符合如下要求:

```sh
cat wav.scp
asr_example1  data/test/audios/asr_example1.wav
asr_example2  data/test/audios/asr_example2.wav
...
```

- 若输入格式wav文件url,api调用方式可参考如下范例:

```python
from modelscope.pipelines import pipeline
from modelscope.utils.constant import Tasks

inference_pipeline = pipeline(
    task=Tasks.auto_speech_recognition,
    model='iic/speech_paraformer-large-vad-punc_asr_nat-zh-cn-16k-common-vocab8404-pytorch',
    model_revision="v2.0.4")

rec_result = inference_pipeline('https://isv-data.oss-cn-hangzhou.aliyuncs.com/ics/MaaS/ASR/test_audio/asr_vad_punc_example.wav')
print(rec_result)
```

- 输入音频为pcm格式,调用api时需要传入音频采样率参数audio_fs,例如:

```python
rec_result = inference_pipeline('https://isv-data.oss-cn-hangzhou.aliyuncs.com/ics/MaaS/ASR/test_audio/asr_vad_punc_example.pcm', fs=16000)
```

- 输入音频为wav格式,api调用方式可参考如下范例:

```python
rec_result = inference_pipeline('asr_vad_punc_example.wav')
```

- 若输入格式为文件wav.scp(注:文件名需要以.scp结尾),可添加 output_dir 参数将识别结果写入文件中,api调用方式可参考如下范例:

```python
inference_pipeline("wav.scp", output_dir='./output_dir')
```
识别结果输出路径结构如下:

```sh
tree output_dir/
output_dir/
└── 1best_recog
    ├── score
    ├── text

1 directory, 4 files
```
score:识别路径得分

text:语音识别结果文件


- 若输入音频为已解析的audio音频,api调用方式可参考如下范例:

```python
import soundfile

waveform, sample_rate = soundfile.read("asr_vad_punc_example.wav")
rec_result = inference_pipeline(waveform)
```

- ASR、VAD、PUNC模型自由组合

可根据使用需求对VAD和PUNC标点模型进行自由组合,使用方式如下:
```python
inference_pipeline = pipeline(
    task=Tasks.auto_speech_recognition,
    model='iic/speech_paraformer-large-vad-punc_asr_nat-zh-cn-16k-common-vocab8404-pytorch', model_revision="v2.0.4",
    vad_model='iic/speech_fsmn_vad_zh-cn-16k-common-pytorch', vad_model_revision="v2.0.4",
    punc_model='iic/punc_ct-transformer_zh-cn-common-vocab272727-pytorch', punc_model_revision="v2.0.3",
    # spk_model="iic/speech_campplus_sv_zh-cn_16k-common",
    # spk_model_revision="v2.0.2",
)
```
若不使用PUNC模型,可配置punc_model="",或不传入punc_model参数,如需加入LM模型,可增加配置lm_model='damo/speech_transformer_lm_zh-cn-common-vocab8404-pytorch',并设置lm_weight和beam_size参数。

## 基于FunASR进行推理

下面为快速上手教程,测试音频([中文](https://isv-data.oss-cn-hangzhou.aliyuncs.com/ics/MaaS/ASR/test_audio/vad_example.wav),[英文](https://isv-data.oss-cn-hangzhou.aliyuncs.com/ics/MaaS/ASR/test_audio/asr_example_en.wav))

### 可执行命令行
在命令行终端执行:

```shell
funasr +model=paraformer-zh +vad_model="fsmn-vad" +punc_model="ct-punc" +input=vad_example.wav
```

注:支持单条音频文件识别,也支持文件列表,列表为kaldi风格wav.scp:`wav_id   wav_path`

### python示例
#### 非实时语音识别
```python
from funasr import AutoModel
# paraformer-zh is a multi-functional asr model
# use vad, punc, spk or not as you need
model = AutoModel(model="paraformer-zh", model_revision="v2.0.4",
                  vad_model="fsmn-vad", vad_model_revision="v2.0.4",
                  punc_model="ct-punc-c", punc_model_revision="v2.0.4",
                  # spk_model="cam++", spk_model_revision="v2.0.2",
                  )
res = model.generate(input=f"{model.model_path}/example/asr_example.wav", 
            batch_size_s=300, 
            hotword='魔搭')
print(res)
```
注:`model_hub`:表示模型仓库,`ms`为选择modelscope下载,`hf`为选择huggingface下载。

#### 实时语音识别

```python
from funasr import AutoModel

chunk_size = [0, 10, 5] #[0, 10, 5] 600ms, [0, 8, 4] 480ms
encoder_chunk_look_back = 4 #number of chunks to lookback for encoder self-attention
decoder_chunk_look_back = 1 #number of encoder chunks to lookback for decoder cross-attention

model = AutoModel(model="paraformer-zh-streaming", model_revision="v2.0.4")

import soundfile
import os

wav_file = os.path.join(model.model_path, "example/asr_example.wav")
speech, sample_rate = soundfile.read(wav_file)
chunk_stride = chunk_size[1] * 960 # 600ms

cache = {}
total_chunk_num = int(len((speech)-1)/chunk_stride+1)
for i in range(total_chunk_num):
    speech_chunk = speech[i*chunk_stride:(i+1)*chunk_stride]
    is_final = i == total_chunk_num - 1
    res = model.generate(input=speech_chunk, cache=cache, is_final=is_final, chunk_size=chunk_size, encoder_chunk_look_back=encoder_chunk_look_back, decoder_chunk_look_back=decoder_chunk_look_back)
    print(res)
```

注:`chunk_size`为流式延时配置,`[0,10,5]`表示上屏实时出字粒度为`10*60=600ms`,未来信息为`5*60=300ms`。每次推理输入为`600ms`(采样点数为`16000*0.6=960`),输出为对应文字,最后一个语音片段输入需要设置`is_final=True`来强制输出最后一个字。

#### 语音端点检测(非实时)
```python
from funasr import AutoModel

model = AutoModel(model="fsmn-vad", model_revision="v2.0.4")

wav_file = f"{model.model_path}/example/asr_example.wav"
res = model.generate(input=wav_file)
print(res)
```

#### 语音端点检测(实时)
```python
from funasr import AutoModel

chunk_size = 200 # ms
model = AutoModel(model="fsmn-vad", model_revision="v2.0.4")

import soundfile

wav_file = f"{model.model_path}/example/vad_example.wav"
speech, sample_rate = soundfile.read(wav_file)
chunk_stride = int(chunk_size * sample_rate / 1000)

cache = {}
total_chunk_num = int(len((speech)-1)/chunk_stride+1)
for i in range(total_chunk_num):
    speech_chunk = speech[i*chunk_stride:(i+1)*chunk_stride]
    is_final = i == total_chunk_num - 1
    res = model.generate(input=speech_chunk, cache=cache, is_final=is_final, chunk_size=chunk_size)
    if len(res[0]["value"]):
        print(res)
```

#### 标点恢复
```python
from funasr import AutoModel

model = AutoModel(model="ct-punc", model_revision="v2.0.4")

res = model.generate(input="那今天的会就到这里吧 happy new year 明年见")
print(res)
```

#### 时间戳预测
```python
from funasr import AutoModel

model = AutoModel(model="fa-zh", model_revision="v2.0.4")

wav_file = f"{model.model_path}/example/asr_example.wav"
text_file = f"{model.model_path}/example/text.txt"
res = model.generate(input=(wav_file, text_file), data_type=("sound", "text"))
print(res)
```

更多详细用法([示例](https://github.com/alibaba-damo-academy/FunASR/tree/main/examples/industrial_data_pretraining))


## 微调

详细用法([示例](https://github.com/alibaba-damo-academy/FunASR/tree/main/examples/industrial_data_pretraining))



## Benchmark
  结合大数据、大模型优化的Paraformer在一序列语音识别的benchmark上获得当前SOTA的效果,以下展示学术数据集AISHELL-1、AISHELL-2、WenetSpeech,公开评测项目SpeechIO TIOBE白盒测试场景的效果。在学术界常用的中文语音识别评测任务中,其表现远远超于目前公开发表论文中的结果,远好于单独封闭数据集上的模型。此结果为[Paraformer-large模型](https://www.modelscope.cn/models/damo/speech_paraformer-large_asr_nat-zh-cn-16k-aishell1-vocab8404-pytorch/summary)在无VAD和标点模型下的测试结果。

### AISHELL-1

| AISHELL-1 test                                   | w/o LM                                | w/ LM                                 |
|:------------------------------------------------:|:-------------------------------------:|:-------------------------------------:|
| <div style="width: 150pt">Espnet</div>           | <div style="width: 150pt">4.90</div>  | <div style="width: 150pt">4.70</div>  | 
| <div style="width: 150pt">Wenet</div>            | <div style="width: 150pt">4.61</div>  | <div style="width: 150pt">4.36</div>  | 
| <div style="width: 150pt">K2</div>               | <div style="width: 150pt">-</div>     | <div style="width: 150pt">4.26</div>  | 
| <div style="width: 150pt">Blockformer</div>      | <div style="width: 150pt">4.29</div>  | <div style="width: 150pt">4.05</div>  |
| <div style="width: 150pt">Paraformer-large</div> | <div style="width: 150pt">1.95</div>  | <div style="width: 150pt">1.68</div>     | 

### AISHELL-2

|           | dev_ios| test_android| test_ios|test_mic|
|:-------------------------------------------------:|:-------------------------------------:|:-------------------------------------:|:------------------------------------:|:------------------------------------:|
| <div style="width: 150pt">Espnet</div>            | <div style="width: 70pt">5.40</div>  |<div style="width: 70pt">6.10</div>  |<div style="width: 70pt">5.70</div>  |<div style="width: 70pt">6.10</div>  |
| <div style="width: 150pt">WeNet</div>             | <div style="width: 70pt">-</div>     |<div style="width: 70pt">-</div>     |<div style="width: 70pt">5.39</div>  |<div style="width: 70pt">-</div>    |
| <div style="width: 150pt">Paraformer-large</div>  | <div style="width: 70pt">2.80</div>  |<div style="width: 70pt">3.13</div>  |<div style="width: 70pt">2.85</div>  |<div style="width: 70pt">3.06</div>  |


### Wenetspeech

|           | dev| test_meeting| test_net|
|:-------------------------------------------------:|:-------------------------------------:|:-------------------------------------:|:------------------------------------:|
| <div style="width: 150pt">Espnet</div>            | <div style="width: 100pt">9.70</div>  |<div style="width: 100pt">15.90</div>  |<div style="width: 100pt">8.80</div>  |
| <div style="width: 150pt">WeNet</div>             | <div style="width: 100pt">8.60</div>  |<div style="width: 100pt">17.34</div>  |<div style="width: 100pt">9.26</div>  |
| <div style="width: 150pt">K2</div>                | <div style="width: 100pt">7.76</div>  |<div style="width: 100pt">13.41</div>  |<div style="width: 100pt">8.71</div>  |
| <div style="width: 150pt">Paraformer-large</div>  | <div style="width: 100pt">3.57</div>  |<div style="width: 100pt">6.97</div>   |<div style="width: 100pt">6.74</div>  |

### [SpeechIO TIOBE](https://github.com/SpeechColab/Leaderboard)

Paraformer-large模型结合Transformer-LM模型做shallow fusion,在公开评测项目SpeechIO TIOBE白盒测试场景上获得当前SOTA的效果,目前[Transformer-LM模型](https://modelscope.cn/models/damo/speech_transformer_lm_zh-cn-common-vocab8404-pytorch/summary)已在ModelScope上开源,以下展示SpeechIO TIOBE白盒测试场景without LM、with Transformer-LM的效果:

- Decode config w/o LM: 
  - Decode without LM
  - Beam size: 1
- Decode config w/ LM:
  - Decode with [Transformer-LM](https://modelscope.cn/models/damo/speech_transformer_lm_zh-cn-common-vocab8404-pytorch/summary)
  - Beam size: 10
  - LM weight: 0.15

| testset | w/o LM | w/ LM |
|:------------------:|:----:|:----:|
|<div style="width: 200pt">SPEECHIO_ASR_ZH00001</div>| <div style="width: 150pt">0.49</div> | <div style="width: 150pt">0.35</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH00002</div>| <div style="width: 150pt">3.23</div> | <div style="width: 150pt">2.86</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH00003</div>| <div style="width: 150pt">1.13</div> | <div style="width: 150pt">0.80</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH00004</div>| <div style="width: 150pt">1.33</div> | <div style="width: 150pt">1.10</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH00005</div>| <div style="width: 150pt">1.41</div> | <div style="width: 150pt">1.18</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH00006</div>| <div style="width: 150pt">5.25</div> | <div style="width: 150pt">4.85</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH00007</div>| <div style="width: 150pt">5.51</div> | <div style="width: 150pt">4.97</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH00008</div>| <div style="width: 150pt">3.69</div> | <div style="width: 150pt">3.18</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH00009</div>| <div style="width: 150pt">3.02</div> | <div style="width: 150pt">2.78</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH000010</div>| <div style="width: 150pt">3.35</div> | <div style="width: 150pt">2.99</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH000011</div>| <div style="width: 150pt">1.54</div> | <div style="width: 150pt">1.25</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH000012</div>| <div style="width: 150pt">2.06</div> | <div style="width: 150pt">1.68</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH000013</div>| <div style="width: 150pt">2.57</div> | <div style="width: 150pt">2.25</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH000014</div>| <div style="width: 150pt">3.86</div> | <div style="width: 150pt">3.08</div> |
|<div style="width: 200pt">SPEECHIO_ASR_ZH000015</div>| <div style="width: 150pt">3.34</div> | <div style="width: 150pt">2.67</div> |


## 使用方式以及适用范围

运行范围
- 支持Linux-x86_64、Mac和Windows运行。

使用方式
- 直接推理:可以直接对输入音频进行解码,输出目标文字。
- 微调:加载训练好的模型,采用私有或者开源数据进行模型训练。

使用范围与目标场景
- 适合与离线语音识别场景,如录音文件转写,配合GPU推理效果更加,输入音频时长不限制,可以为几个小时音频。


## 模型局限性以及可能的偏差

考虑到特征提取流程和工具以及训练工具差异,会对CER的数据带来一定的差异(<0.1%),推理GPU环境差异导致的RTF数值差异。



## 相关论文以及引用信息

```BibTeX
@inproceedings{gao2022paraformer,
  title={Paraformer: Fast and Accurate Parallel Transformer for Non-autoregressive End-to-End Speech Recognition},
  author={Gao, Zhifu and Zhang, Shiliang and McLoughlin, Ian and Yan, Zhijie},
  booktitle={INTERSPEECH},
  year={2022}
}
```