Real-Time Auralisation of Outdoor Sound Propagation

Overview & Synopsis

Auralisation describes the process of generating and presenting audible sound using computer programs and audio hardware. Since the result is perceived naturally by the human's auditory system, a demonstration by means of auralisation is easily comprehensible and neither requires background knowledge nor expertise. Producing auralisation under real-time constraints increases the implementation demands significantly. Real-time auralisation is required in applications that respond to user interaction, for example, in interactive Virtual Reality (VR) environments. The realisation of a real-time auralisation application for outdoor environments represents a promising addition to current noise assessment procedures. It also delivers the foundation for the auditory modality in outdoor VR scenarios, which can serve as as an audio-video tool for perception-related scientific investigations. Traditional approaches often neglect the time-variant characteristic of dynamically moving sound sources and receivers, treating an acoustic environment as temporarily static on a frame-by-frame basis. Adaption to dynamic events is implemented by transition of sequences of time-invariant simulations, which is contradictory to the highly dynamic nature of outdoor scenarios. This book describes a system that attaches increased importance to fast geometric diffraction simulations and employs an audio rendering network that reflects the time-variant nature of dynamic outdoor sound propagation.