A local representation of the head-related transfer function

Abstract

Spatial descriptions of the head-related transfer function (HRTF) using spherical harmonics, which is commonly used for the purpose, consider all directions simultaneously. However, in perceptual studies, it is necessary to model HRTFs with different angular resolutions at different directions. To this end, an alternative spatial representation of the HRTF, based on local analysis functions, is introduced. The proposal is shown to have the potential to describe the local features of the HRTF. This is verified by comparing the reconstruction error achieved by the proposal to that of the spherical harmonic decomposition when reconstructing the HRTF inside a spherical cap.

Efficient Representation of Head-Related Transfer Functions With Combination of Spherical Harmonics and Spherical Wavelets

“…An assumption may also be made that the low order spherical harmonics modeling for the coarse structure correspond to the head shadow effect, while this interpretation becomes difficult for the modeling of HRTF local features which always requires complex combination of high order spherical harmonics. It has been shown there is a correspondence between the HRTF local features and higher level expansion coefficients of the spherical wavelets [29], [30]. The residual finer detail modeled by the spherical wavelet expansion may be more related to the pinna effect filtering.…”

“…The spatial patterns of HRTFs consist of different spatial variations and shapes in different local regions that are called local features on the sphere. Recently, a new method is proposed to model the HRTFs with spherical wavelets, which shows a better performance of capturing the HRTF local features than the spherical harmonic method [29], [30]. Besides, locally modeling HRTF spatial patterns further allows for controlling the spatial resolutions in space with the expansion coefficients.…”

Super-Resolution in Near-Field Acoustic Time Reversal Using Reverberated Elastic Waves in Skull-Shaped Antenna

“…It is well known [1] that anatomy contributes to the 27 task of auditory source localization, as its effects on an 28 acoustic signal, described by the head-related transfer 29 function (HRTF) [37,21], can be seen as a spectral fil-30 ter and depend on the location of the signal's source. 31 Human auditory source localization mostly relies on Building on the work of Catheline et al [7], we ex-38 plore here the specific role of elastic waves mediated 39 in a skull-shaped object mimicking bone-conducted 40 sound.…”