Exploiting deep neural networks and head movements for binaural localisation of multiple speakers in reverberant conditions

This paper presents a novel machine-hearing system that ex- ploits deep neural networks (DNNs) and head movements for binaural localisation of multiple speakers in reverberant conditions. DNNs are used to map binaural features, consisting of the complete cross-correlation function (CCF) and interaural level differences (ILDs), to the source azimuth. Our approach was evaluated using a localisation task in which sources were located in a full 360-degree azimuth range. As a result, front- back confusions often occurred due to the similarity of binaural features in the front and rear hemifields. To address this, a head movement strategy was incorporated in the DNN-based model to help reduce the front-back errors. Our experiments show that, compared to a system based on a Gaussian mixture model (GMM) classifier, the proposed DNN system substantially re- duces localisation errors under challenging acoustic scenarios in which multiple speakers and room reverberation are present.