Applications of 3-Dimensional Spherical Transforms to Acoustics and Personalization of Head-related Transfer Functions (HRTFs)

The spherical harmonic transform (SHT), which returns spatial frequency components of data or distributions determined on the unit sphere, has found many applications in acoustics, such as spatial sound capture and reproduction, beamforming with spherical arrays, analysis of transducer radiation patterns, interpolation of head-related transfer functions (HRTFs) and others. However the SHT is a 2-dimensional transform, not suited for 3-dimensional data that vary not only with angle but additionally across the radial dimension. This work examines two 3-dimensional spherical transforms, namely the spherical Fourier-Bessel transform (SFBT) and the spherical harmonic oscillator transform (SHOT), and considers their potential uses in acoustics. The study presents preliminary results on their application to personalization of HRTFs, avoiding the cumbersome task of measuring them directly. Assuming that head-shape similarity correlates to some extent with HRTF similarity, we employ the aforementioned transforms to get a spectral representation of the user’s head scan, and determine its distance from the spectra of head scans associated with the HRTF database.

Speaker Details

Archontis Politis obtained his M.Eng. degree in civil engineering at Aristotle’s University of Thessaloniki, Greece, and his M.Sc. degree in sound & vibration studies at ISVR, University of Southampton, UK, in 2006 and 2008 respectively. From 2008 to 2010 he worked as a graduate acoustic consultant at Arup Acoustics, Glasgow, UK, and as a researcher in a joint collaboration between Arup Acoustics and the Glasgow School of Arts, on interactive auralization of architectural spaces using 3D sound techniques. He is currently pursuing a doctoral degree at Aalto University, Finland, in the field of parametric spatial sound recording, analysis and reproduction.

Date:
Speakers:
Archontis Politis
Affiliation:
Aalto University

Series: Microsoft Research Talks