Considerations regarding individualization of head-related transfer functions

This paper provides some considerations regarding using individualized head-related transfer functions for rendering binaural spatial audio over headphones. It briefly considers the degree of benefit that individualization may provide. It then examines the degree of variation existing within the ear morphology across listeners within the Sydney-York Morphological and Recording of Ears (SYMARE) database using kernel principal component analysis and the large deformation diffeomorphic metric mapping framework. The degree of variation across listeners in the directivity patterns associated with head-related transfer functions is also analyzed as a function of frequency. The variation in ear morphology is related to the variation in the directivity patterns using simple linear regression.