Perceptually-Guided Acoustic "Foveation"

Realistic spatial audio rendering improves immersion in virtual environments. However, the computational complexity of acoustic propagation increases linearly with the number of sources. Consequently, real-time accurate acoustic rendering becomes challenging in highly dynamic scenarios such as virtual and augmented reality (VR/AR). Exploiting the fact that human spatial sensitivity of acoustic sources is not equal at azimuth eccentricities in the horizontal plane, we introduce a perceptually-aware acoustic "foveation"guidance model to the audio rendering pipeline, which can integrate audio sources that are not spatially resolvable by human listeners. To this end, we first conduct a series of psychophysical studies to measure the minimum resolvable audible angular distance under various spatial and background conditions. We leverage this data to derive an azimuth-characterized real-time acoustic foveation algorithm. Numerical analysis and subjective user studies in VR environments demonstrate our method's effectiveness in significantly reducing acoustic rendering workload, without compromising users' spatial perception of audio sources. We believe that the presented research will motivate future investigation into the new frontier of modeling and leveraging human multimodal perceptual limitations - beyond the extensively studied visual acuity - for designing efficient VR/AR systems.