IPDnet: A Universal Direct-Path IPD Estimation Network for Sound Source Localization

TL;DR

IPDnet is a neural network designed to accurately estimate direct-path inter-channel phase differences for sound source localization, adaptable to various microphone array configurations and effective in complex acoustic environments.

Contribution

The paper introduces a novel full-band and narrow-band fusion network with a multi-track learning target for flexible and robust sound source localization.

Findings

Achieves high localization accuracy in simulated and real-world tests.

Generalizes well to unseen microphone array configurations.

Effective in localizing multiple moving sound sources.

Abstract

Extracting direct-path spatial feature is crucial for sound source localization in adverse acoustic environments. This paper proposes the IPDnet, a neural network that estimates direct-path inter-channel phase difference (DP-IPD) of sound sources from microphone array signals. The estimated DP-IPD can be easily translated to source location based on the known microphone array geometry. First, a full-band and narrow-band fusion network is proposed for DP-IPD estimation, in which alternating narrow-band and full-band layers are responsible for estimating the rough DP-IPD information in one frequency band and capturing the frequency correlations of DP-IPD, respectively. Second, a new multi-track DP-IPD learning target is proposed for the localization of flexible number of sound sources. Third, the IPDnet is extend to handling variable microphone arrays, once trained which is able to process arbitrary microphone arrays with different number of channels and array topology. Experiments of multiple-moving-speaker localization are conducted on both simulated and real-world data, which show that the proposed full-band and narrow-band fusion network and the proposed multi-track DP-IPD learning target together achieves excellent sound source localization performance. Moreover, the proposed variable-array model generalizes well to unseen microphone arrays.