Towards Bone-Conducted Vibration Speech Enhancement on Head-Mounted Wearables.

Head-mounted wearables are rapidly growing in popularity. However, a gap exists in providing robust voice-related applications like conversation or command control in complex environments, such as competing speakers and strong noises. The compact design of HMWs introduces non-trivial challenges to existing speech enhancement systems that use microphone recording only. In this paper, we handle this problem by using bone vibration conducted through the head skull. The principle is that the accelerometer is widely installed on head-mounted wearables and can capture the clean user's voice. Hence, we develop VibVoice , a lightweight multi-modal speech enhancement system for head-mounted wearables. We design a two-branch encoder-decoder deep neural network to fuse the high-level features of the two modalities and reconstruct clean speech. To address the issue of insufficient paired data for training, we extensively measure the bone conduction effect from a limited dataset to extract the physical impulse function for cross-modal data augmentation. We evaluate VibVoice on a dataset collected in real world and compare it with two state-of-the-art baselines. Results show that VibVoice yields up to 21% better performance in PESQ and up to 26% better performance in SNR compared with the baseline with 72 times less paired data required. We also conduct a user study with 35 participants, in which 87% participants prefer VibVoice compared with the baseline. In addition, VibVoice requires 4 to 31 times less execution time compared with baselines on mobile devices. The demo audio of VibVoice is available at https://www.youtube.com/watch?v=8_-s_C_NGRI.