Bone-conduction Guided Multimodal Speech Enhancement with Conditional Diffusion Models
Sina Khanagha, Bunlong Lay, Timo Gerkmann
TL;DR
This work tackles robust speech enhancement under severe noise by fusing noise-immune bone-conduction data with air-conducted audio through a conditional diffusion framework. It introduces the Bone-conduction Conditional Diffusion Model (BCDM) with two conditioning strategies (Input Concatenation and Decoder Conditioning) built on a modified NCSN++ backbone, and formulates the forward SDE $dx_t = f(x_t, t) dt + g(t) dW_t$ with a score model $s_ heta(x_t, y, y_c, t)$ trained via score matching. Experiments on the ABCS/CHiME3 setup show BCDM outperforms recent multimodal baselines and a strong single-modal diffusion baseline across a wide range of SNRs, with IC offering superior efficiency and DC delivering higher instrumental metrics at higher cost. This demonstrates the viability of conditional diffusion for bone-conduction guided speech enhancement and suggests practical gains for robust hearing aids and communication systems. Overall, the work establishes a new multimodal, diffusion-based paradigm that exploits complementary bone-conduction signals to overcome noise in single-channel scenarios.
Abstract
Single-channel speech enhancement models face significant performance degradation in extremely noisy environments. While prior work has shown that complementary bone-conducted speech can guide enhancement, effective integration of this noise-immune modality remains a challenge. This paper introduces a novel multimodal speech enhancement framework that integrates bone-conduction sensors with air-conducted microphones using a conditional diffusion model. Our proposed model significantly outperforms previously established multimodal techniques and a powerful diffusion-based single-modal baseline across a wide range of acoustic conditions.
