Conformer-1: Robust ASR via Large-Scale Semisupervised Bootstrapping

Kevin Zhang; Luka Chkhetiani; Francis McCann Ramirez; Yash Khare; Andrea Vanzo; Michael Liang; Sergio Ramirez Martin; Gabriel Oexle; Ruben Bousbib; Taufiquzzaman Peyash; Michael Nguyen; Dillon Pulliam; Domenic Donato

arXiv · 2404.07341

Conformer-1: Robust ASR via Large-Scale Semisupervised Bootstrapping

Kevin Zhang·Luka Chkhetiani·Francis McCann Ramirez·Yash Khare·Andrea Vanzo·Michael Liang·Sergio Ramirez Martin·Gabriel Oexle·Ruben Bousbib·Taufiquzzaman Peyash·Michael Nguyen·Dillon Pulliam·Domenic Donato

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Abstract

This paper presents Conformer-1, an end-to-end Automatic Speech Recognition (ASR) model trained on an extensive dataset of 570k hours of speech audio data, 91% of which was acquired from publicly available sources. To achieve this, we perform Noisy Student Training after generating pseudo-labels for the unlabeled public data using a strong Conformer RNN-T baseline model. The addition of these pseudo-labeled data results in remarkable improvements in relative Word Error Rate (WER) by 11.5% and 24.3% for our asynchronous and realtime models, respectively. Additionally, the model is more robust to background noise owing to the addition of these data. The results obtained in this study demonstrate that the incorporation of pseudo-labeled publicly available data is a highly effective strategy for improving ASR accuracy and noise robustness.

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BibTeX RIS

Kevin Zhang, Luka Chkhetiani, Francis McCann Ramirez, Yash Khare, Andrea Vanzo, Michael Liang, Sergio Ramirez Martin, Gabriel Oexle, Ruben Bousbib, Taufiquzzaman Peyash, Michael Nguyen, Dillon Pulliam, Domenic Donato. 2024-04-10. Conformer-1: Robust ASR via Large-Scale Semisupervised Bootstrapping. https://arxiv.org/abs/2404.07341

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