Binaural rendering from microphone array signals of arbitrary geometry

TL;DR

A method based on harmonic analysis of infinite order, which allows the use of arbitrarily placed microphones for binaural rendering from microphone array signals of arbitrary geometry is proposed and is robust against change in listening position in the recording area.

Abstract

A method of binaural rendering from microphone array signals of arbitrary geometry is proposed. To reproduce binaural signals from microphone array recordings at a remote location, a spherical microphone array is generally used for capturing a soundfield. However, owing to the lack of flexibility in the microphone arrangement, the single spherical array is sometimes impractical for estimating a large region of a soundfield. We propose a method based on harmonic analysis of infinite order, which allows the use of arbitrarily placed microphones. In the synthesis of the estimated soundfield, a spherical-wave-decomposition-based binaural rendering is also formulated to take into consideration the distance in measuring head-related transfer functions. We develop and evaluate a composite microphone array consisting of multiple small arrays. Experimental results including those of listening tests indicate that our proposed method is robust against change in listening position in the recording area.

Figures (13)

• Figure 1: Geometry for HRTF measurement in spherical coordinates. The transfer functions from the loudspeaker on a spherical surface $\partial\Omega$ to the listener's left and right eardrums are obtained.
• Figure 2: NMSEs with respect to azimuth angle of point source at $r_{\mathrm{ps}}=2.0~\mathrm{m}$ and frequency.
• Figure 3: Amplitude response of binaural signal of left ear for point source at $(2.0~\mathrm{m},90^{\circ},-90^{\circ})$ with respect to frequency.
• Figure 4: SD with respect to azimuth angle of point source at $r_{\mathrm{ps}}=2.0~\mathrm{m}$.
• Figure 5: SD with respect to point source distance.