Morphoacoustic perturbation analysis: principles and validation

Anthony Tew , Carl Hetherington , Jonathan Thorpe

This paper presents a frequency domain technique for investigating the relationship between acoustic properties of the human hearing system and the morphology responsible for creating them. Exploiting reciprocity, the boundary element method is applied to determine head-related transfer functions (HRTFs) for various directions and distances from a surface mesh model of a head and pinnae. Small orthogonal surface harmonic deformations are applied to the mesh one at a time and stored in a database together with the resulting, approximately linear, changes to the HRTFs (delta HRTFs). Once the computationally intensive process of constructing the database has been completed, identifying the morphological origins of arbitrary acoustic spectral features is very rapid. A weight for each database harmonic is determined according to how strongly its delta HRTF influences the acoustic feature of interest. The same weights are then used to sum the corresponding orthogonal deformations. Regions of high deformation are chiefly responsible for creating that acoustic feature. The method, which we term morphoacoustic perturbation analysis, will be described in greater detail and preliminary results which have been validated by direct acoustic measurement will be presented.

Mots clés: binaural; morphology; HRTF; perturbation

Domaines: Acoustique [physics.class-ph]

Anthony Tew, Carl Hetherington, Jonathan Thorpe. Morphoacoustic perturbation analysis: principles and validation. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00811131⟩