Benchmarking Japanese Speech Recognition on ASR-LLM Setups with Multi-Pass Augmented Generative Error Correction
Yuka Ko, Sheng Li, Chao-Han Huck Yang, Tatsuya Kawahara
TL;DR
This work addresses improving Japanese ASR transcripts through generative error correction (GER) using large language models (LLMs). It introduces a multi-pass augmented GER (MPA GER) that combines multiple ASR hypotheses with outputs from several LLMs and merges them, leveraging ROVER-like voting to mitigate hallucinations. The approach is evaluated on SPREDS-U1-ja and CSJ using Elyza-7b and Qwen1.5-7b, demonstrating CER improvements over standard LLM GER and traditional combination methods, with notable gains for short utterances. The findings highlight the value of cross-model diversity in post-editing ASR outputs and point to broader applicability of LLM-based GER in low-cer, high-accuracy regimes for Japanese and potentially other languages.
Abstract
With the strong representational power of large language models (LLMs), generative error correction (GER) for automatic speech recognition (ASR) aims to provide semantic and phonetic refinements to address ASR errors. This work explores how LLM-based GER can enhance and expand the capabilities of Japanese language processing, presenting the first GER benchmark for Japanese ASR with 0.9-2.6k text utterances. We also introduce a new multi-pass augmented generative error correction (MPA GER) by integrating multiple system hypotheses on the input side with corrections from multiple LLMs on the output side and then merging them. To the best of our knowledge, this is the first investigation of the use of LLMs for Japanese GER, which involves second-pass language modeling on the output transcriptions generated by the ASR system (e.g., N-best hypotheses). Our experiments demonstrated performance improvement in the proposed methods of ASR quality and generalization both in SPREDS-U1-ja and CSJ data.
