Application of head-related transfer functions for binaural synthesis

Abstract

Binaural synthesis offers a method for creating a truly immersive three-dimensional auditory environment. The sound output is produced by convolving a sound input with sets of head-related transfer functions (HRTFs). The result is a set of two signals typically reproduced by means of headphones, and the technique is therefore well suited for systems with limited hardware for sound reproduction, such as most multimedia systems. In the present paper, HRTFs are presented in the time and frequency domains, and are commented upon in relation to their application for binaural synthesis using digital signal processing. Results obtained from experiments conducted at the Acoustics Laboratory at Aalborg University in Denmark are reviewed, giving hints for the selection of filter lengths, update rate, and spatial resolution for dynamic environments.