title: Source and listener directivity for interactive wave-based sound propagation.
abstract: We present an approach to model dynamic, data-driven source and listener directivity for interactive wave-based sound propagation in virtual environments and computer games. Our directional source representation is expressed as a linear combination of elementary spherical harmonic (SH) sources. In the preprocessing stage, we precompute and encode the propagated sound fields due to each SH source. At runtime, we perform the SH decomposition of the varying source directivity interactively and compute the total sound field at the listener position as a weighted sum of precomputed SH sound fields. We propose a novel plane-wave decomposition approach based on higher-order derivatives of the sound field that enables dynamic HRTF-based listener directivity at runtime. We provide a generic framework to incorporate our source and listener directivity in any offline or online frequency-domain wave-based sound propagation algorithm. We have integrated our sound propagation system in Valve's Source game engine and use it to demonstrate realistic acoustic effects such as sound amplification, diffraction low-passing, scattering, localization, externalization, and spatial sound, generated by wave-based propagation of directional sources and listener in complex scenarios. We also present results from our preliminary user study.
authors.affiliation: UNC Chapel Hill.
authors.forename: Ravish
authors.initials: R
authors.lastname: Mehra
authors.affiliation: UNC Chapel Hill.
authors.forename: Lakulish
authors.initials: L
authors.lastname: Antani
authors.affiliation: UNC Chapel Hill.
authors.forename: Sujeong
authors.initials: S
authors.lastname: Kim
authors.affiliation: UNC Chapel Hill.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Manocha
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods*; D003198:Computer Simulation; D006801:Humans; D008962:Models, Theoretical; D012542:Scattering, Radiation; D013016:Sound; D013017:Sound Localization / Q000502:physiology*; D013018:Sound Spectrography / Q000379:methods*; D013647:Task Performance and Analysis; D014584:User-Computer Interface