Interpolation of scheduled simulation results for real-time auralization

Abstract

The approach of auralization allows rendering plausible audio signals based on purely synthesized data. One key aspect for this is the simulation of sound propagation. Using sophisticated physics-based models, even complex situations—like sound propagation through an inhomogeneous, moving atmosphere—can be considered. However, even with fast approaches based on geometrical acoustics such simulations might not be real-time capable when being integrated in the auralization processing chain. This is because the update rate of the simulations is significantly lower than the audio block rate which can lead to artifacts, especially when considering effects like the Doppler shift. In this contribution, we propose a method aiming to run an artifact-free auralization despite a relatively low and potentially irregular simulation update rate. For this purpose, the simulations are run in a thread separate from the main processing chain and the respective outputs are interpolated. The method is applied to an aircraft flyover scenario considering curved sound propagation in a stratified, moving atmosphere.