Extending X3D Realism with Audio Graphs, Acoustic Properties and 3D Spatial Sound

A fundamental requirement for both realistic modeling and immersive presence is spatial audio, correctly rendering the presentation of each object with aural characteristics. Auditory attributes involve perceived directions, distances, and the propagation paths from complex sound sources to each listener in a potentially complex 3D scene. Many long-running efforts in both hardware and software have improved the ability to aurally render high-fidelity spatialized sound in real time. Motivated by current progress, this work proposes integrating acoustic properties associated with geometric shapes together with 3D spatial sound in the X3D Graphics standard. This combination is possible by exploiting the structure and functionality of Web Audio API, an effective framework for processing and synthesizing audio in Web applications. The paper describes design patterns and initial implement work for this spatial composition of audio graphs and scene graphs. Both specifications are device neutral, without dependencies on specific platforms or audio hardware. Examples for evaluation lead to useful conclusions and areas for future model development.