Modeling and Customization of Head-Related Impulse Responses Based on General Basis Functions in Time Domain

Abstract

This study deals with modeling and customization of head-related impulse responses (HRIRs) in the median plane based on general basis functions. To clarify whether the 12 principal components (PCs) obtained from principal components analysis of the median-plane HRIRs in the CIPIC HRTF database can be general basis functions to model arbitrary subject's median-plane HRIRs, which are not included in the process to obtain the basis functions, a series of subjective listening tests and an error analysis in the least-squares sense were carried out using the measured and modeled HRIRs. The results showed that the set of individual HRIRs, which were measured using different measurement conditions, techniques, and source positions from the CIPIC dataset, can be modeled with reasonable accuracy. All subjects reported accurate elevation perception in the median plane with the modeled HRIRs from the general basis functions. A novel HRIR customization method based on subjective tuning of the general basis functions was proposed. At each elevation, the only three weights of dominant basis functions corresponding to the three largest inter-subject variations were tuned by a subject and the weights of other basis functions were just mean values of all subjects in the CIPIC HRTF database. In the subjective listening test results, all subjects reported dramatically improved performances for the vertical perception and the front-back discrimination with the customized HRIRs than those with the non-individual HRIRs.