An Asynchronous WFST-Based Decoder for Automatic Speech Recognition

  title={An Asynchronous WFST-Based Decoder for Automatic Speech Recognition},
  author={Hang Lv and Zhehuai Chen and Hainan Xu and Daniel Povey and Lei Xie and Sanjeev Khudanpur},
  journal={ICASSP 2021 - 2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)},
  • Hang Lv, Zhehuai Chen, S. Khudanpur
  • Published 16 March 2021
  • Computer Science
  • ICASSP 2021 - 2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
We introduce asynchronous dynamic decoder, which adopts an efficient A* algorithm to incorporate big language models in the one-pass decoding for large vocabulary continuous speech recognition. Unlike standard one-pass decoding with on-the-fly composition decoder which might induce a significant computation overhead, the asynchronous dynamic decoder has a novel design where it has two fronts, with one performing "exploration" and the other "backfill". The computation of the two fronts… 

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