🤖 AI Summary
This work addresses the limitation of existing self-supervised speech learning methods, which typically support only a single sampling rate and suffer performance degradation when trained on mixed-rate data due to temporal resolution mismatches. To overcome this, we propose MSR-HuBERT, the first framework enabling multi-sampling-rate self-supervised pretraining without resampling. MSR-HuBERT introduces a multi-sampling-rate adaptive downsampling CNN that maps raw waveforms of varying sampling rates—ranging from 16 kHz to 48 kHz—to a unified time resolution while preserving their original structure, thereby maintaining compatibility with HuBERT’s masked prediction objective and Transformer encoder. Experiments demonstrate that MSR-HuBERT outperforms standard HuBERT in both automatic speech recognition and full-band speech reconstruction tasks, effectively retaining high-frequency details and low-frequency semantic structures.
📝 Abstract
Self-supervised learning (SSL) has advanced speech processing. However, existing speech SSL methods typically assume a single sampling rate and struggle with mixed-rate data due to temporal resolution mismatch. To address this limitation, we propose MSRHuBERT, a multi-sampling-rate adaptive pre-training method. Building on HuBERT, we replace its single-rate downsampling CNN with a multi-sampling-rate adaptive downsampling CNN that maps raw waveforms from different sampling rates to a shared temporal resolution without resampling. This design enables unified mixed-rate pre-training and fine-tuning. In experiments spanning 16 to 48 kHz, MSRHuBERT outperforms HuBERT on speech recognition and full-band speech reconstruction, preserving high-frequency detail while modeling low-frequency semantic structure. Moreover, MSRHuBERT retains HuBERT's mask-prediction objective and Transformer encoder, so existing analyses and improvements that were developed for HuBERT can apply directly.