HRTF range extrapolation by spherical harmonics decomposition

Speaker: Lauréline Perotin

Date: June 22, 2017

Abstract:

In order to locate sound in space, to know from which direction it comes from but also from how far away, our brain analyses all the distortions applied the soundwave from its (estimated) origin to our eardrums. Those reflections, diffractions and other propagation-related transformations are contained in the Head-Related Transfer Functions (HRTFs). Even in an anechoic environment, those filters are different for each individual, each ear and each source position, because we all have different bodies and pinnae. It is thus very complex to measure them for every situation.

In my internship, I worked on a technique to get rid of the distance dependency. Knowing the HRTs of a listener for a given distance and using the wave propagation equations, it is possible to estimate them at another distance. I also evaluated the actual contribution of this method with a perceptual test.