Reverberant Sound Localization with a Robot Head Based on Direct-Path Relative Transfer Function

Abstract

This paper addresses the problem of sound-source localization (SSL) with a robot head, which remains a challenge in real-world environments. In particular we are interested in locating speech sources, as they are of high interest for human-robot interaction. The microphone-pair response corresponding to the direct-path sound propagation is a function of the source direction. In practice, this response is contaminated by noise and reverberations. The direct-path relative transfer function (DP-RTF) is defined as the ratio between the direct-path acoustic transfer function (ATF) of the two microphones, and it is an important feature for SSL. We propose a method to estimate the DP-RTF from noisy and reverberant signals in the short-time Fourier transform (STFT) domain. First, the convolutive transfer function (CTF) approximation is adopted to accurately represent the impulse response of the microphone array, and the first coefficient of the CTF is mainly composed of the direct-path ATF. At each frequency, the frame-wise speech auto- and cross-power spectral density (PSD) are obtained by spectral subtraction. Then a set of linear equations is constructed by the speech auto- and cross-PSD of multiple frames, in which the DP-RTF is an unknown variable, and is estimated by solving the equations. Finally, the estimated DP-RTFs are concatenated across frequencies and used as a feature vector for SSL. Experiments with a robot, placed in various reverberant environments, show that the proposed method outperforms two state-of-the-art methods.

IEEE/RSJ International Conference on Intelligent Robots and Systems,

References in corpus (5)

• Robust Localization and Tracking of Simultaneous Moving Sound Sources Using Beamforming and Particle Filtering
• Localization of Simultaneous Moving Sound Sources for Mobile Robot Using a Frequency-Domain Steered Beamformer Approach
• A Geometric Approach to Sound Source Localization from Time-Delay Estimates
• Acoustic Space Learning for Sound Source Separation and Localization on Binaural Manifolds
• Co-Localization of Audio Sources in Images Using Binaural Features and Locally-Linear Regression

Cited by in corpus (5)

• A Survey of Sound Source Localization with Deep Learning Methods
• Online Localization and Tracking of Multiple Moving Speakers in Reverberant Environments
• Multiple-Speaker Localization Based on Direct-Path Features and Likelihood Maximization with Spatial Sparsity Regularization
• A Review on Sound Source Localization in Robotics: Focusing on Deep Learning Methods
• BERP: A Blind Estimator of Room Parameters for Single-Channel Noisy Speech Signals