Binaural Rendering From Distributed Microphone Signals Considering Loudspeaker Distance in Measurements

A method of binaural rendering from distributed microphone recordings that takes loudspeaker distance for measuring head-related transfer function (HRTF) into consideration is proposed. In general, to reproduce the binaural signals from the signals captured by multiple microphones in the recording area, the captured sound field is represented by plane-wave decomposition. Thus, HRTF is approximated as a transfer function from a plane-wave source in binaural rendering. To incorporate the distance in HRTF measurements, we propose a method based on the spherical-wave decomposition of a sound field, in which the HRTF is assumed to be measured from a point source. Result of experiments using HRTFs calculated by the boundary element method indicated that the accuracy of binaural signal reproduction by the proposed method based on the spherical-wave decomposition was higher than that by the plane-wave-decomposition-based method. We also evaluate the performance of signal conversion from distributed microphone measurements into binaural signals.