Title
Efficient Real Spherical Harmonic Representation of Head-Related Transfer Functions
Abstract
Several methods have recently been proposed for modeling spatially-continuous head-related transfer functions (HRTFs) using techniques based on finite-order spherical harmonic expansion. These techniques inherently impart some amount of spatial smoothing to the measured HRTFs. However, the effect this spatial smoothing has on the localization accuracy has not been analyzed. Consequently, the relationship between the order of a spherical harmonic representation for HRTFs and the maximum localization ability that can be achieved with that representation remains unknown. The present study investigates the effect that spatial smoothing has on virtual sound source localization by systematically reducing the order of a spherical-harmonic-based HRTF representation. Results of virtual localization tests indicate that accurate localization performance is retained with spherical harmonic representations as low as fourth-order, and several important physical HRTF cues are shown to be present even in a first-order representation. These results suggest that listeners do not rely on the fine details in an HRTF’s spatial structure and imply that some of the theoretically-derived bounds for HRTF sampling may be exceeding perceptual requirements.
Year
DOI
Venue
2015
10.1109/JSTSP.2015.2421876
Selected Topics in Signal Processing, IEEE Journal of  
Keywords
Field
DocType
head-related transfer functions,spatial hearing,spherical harmonic,acoustics,accuracy,harmonic analysis,interpolation,transfer functions
Computer vision,Computer science,Interpolation,Spherical harmonics,Harmonic analysis,Smoothing,Transfer function,Sampling (statistics),Artificial intelligence,Spatial structure,Acoustic source localization
Journal
Volume
Issue
ISSN
PP
99
1932-4553
Citations 
PageRank 
References 
5
0.64
4
Authors
4
Name
Order
Citations
PageRank
Griffin D. Romigh1103.40
Douglas S. Brungart250.64
Richard M. Stern31663406.79
Brian D. Simpson4398.77