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arXiv · 2005.03191

ContextNet: Improving Convolutional Neural Networks for Automatic Speech Recognition with Global Context

Wei Han·Zhengdong Zhang·Yu Zhang·Jiahui Yu·Chung-Cheng Chiu·James Qin·Anmol Gulati·Ruoming Pang·Yonghui Wu
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Abstract

Convolutional neural networks (CNN) have shown promising results for end-to-end speech recognition, albeit still behind other state-of-the-art methods in performance. In this paper, we study how to bridge this gap and go beyond with a novel CNN-RNN-transducer architecture, which we call ContextNet. ContextNet features a fully convolutional encoder that incorporates global context information into convolution layers by adding squeeze-and-excitation modules. In addition, we propose a simple scaling method that scales the widths of ContextNet that achieves good trade-off between computation and accuracy. We demonstrate that on the widely used LibriSpeech benchmark, ContextNet achieves a word error rate (WER) of 2.1%/4.6% without external language model (LM), 1.9%/4.1% with LM and 2.9%/7.0% with only 10M parameters on the clean/noisy LibriSpeech test sets. This compares to the previous best published system of 2.0%/4.6% with LM and 3.9%/11.3% with 20M parameters. The superiority of the proposed ContextNet model is also verified on a much larger internal dataset.

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BibTeXRIS

Wei Han, Zhengdong Zhang, Yu Zhang, Jiahui Yu, Chung-Cheng Chiu, James Qin, Anmol Gulati, Ruoming Pang, Yonghui Wu. 2020-05-16. ContextNet: Improving Convolutional Neural Networks for Automatic Speech Recognition with Global Context. https://arxiv.org/abs/2005.03191

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