Papers › Espresso: A Fast End-to-end Neural Speech Recognition Toolkit

Espresso: A Fast End-to-end Neural Speech Recognition Toolkit

18 Sep 2019arXiv:1909.08723archive 2025-07-28

Yiming Wang, Tongfei Chen, Hainan Xu, Shuoyang Ding, Hang Lv, Yiwen Shao, Nanyun Peng, Lei Xie, Shinji Watanabe, Sanjeev Khudanpur

We present Espresso, an open-source, modular, extensible end-to-end neural automatic speech recognition (ASR) toolkit based on the deep learning library PyTorch and the popular neural machine translation toolkit fairseq. Espresso supports distributed training across GPUs and computing nodes, and features various decoding approaches commonly employed in ASR, including look-ahead word-based language model fusion, for which a fast, parallelized decoder is implemented. Espresso achieves state-of-the-art ASR performance on the WSJ, LibriSpeech, and Switchboard data sets among other end-to-end systems without data augmentation, and is 4--11x faster for decoding than similar systems (e.g. ESPnet).

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Tasks

Automatic Speech RecognitionAutomatic Speech Recognition (ASR)Data AugmentationDecoderLanguage ModelingLanguage ModellingMachine TranslationSpeech RecognitionTranslationspeech-recognition

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Speech Recognition Hub5'00 CallHome Espresso Word Error Rate (WER) 19.1 #1 of 1 Archive leaderboard report
Speech Recognition Hub5'00 SwitchBoard Espresso Eval2000 9.2 #5 of 5 Archive leaderboard report
Speech Recognition LibriSpeech test-clean Espresso Word Error Rate (WER) 2.8 #44 of 64 Archive leaderboard report
Speech Recognition LibriSpeech test-other Espresso Word Error Rate (WER) 8.7 #44 of 53 Archive leaderboard report
Speech Recognition WSJ eval92 Espresso Word Error Rate (WER) 3.4 #10 of 17 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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