Creating interactive virtual auditory environments - Computer Graphics and Applications, IEEE

IEEE Computer Graphics and Applications 49 Sound rendering 1 is analogous to graphics rendering when creating virtual auditory environments. In graphics, we can create images by calculating the distribution of light within a modeled environment. Illumination methods such as ray tracing and radiosity are based on the physics of light propagation and reflection. Similarly, sound rendering is based on physical laws of sound propagation and reflection. In this article, we aim to clarify real-time sound rendering techniques by comparing them to visual image rendering. We also describe how to perform sound rendering, based on the knowledge of sound source(s) and listener locations, radiation characteristics of sound sources, geometry of 3D models, and material absorption data—in other words, the congruent data used for graphics rendering. In several instances, we use the Digital Interactive Virtual Acoustics (DIVA) auralization system, which we’ve been developing since 1994 at the Helsinki University of Technology, as a practical example to illustrate a concept. (The sidebar “Practical Applications of the DIVA System” [next page] briefly describes two applications of our system.) In the context of sound rendering, the term auralization—making audible—corresponds to visualization. Applications of sound rendering vary from film effects, computer games, and other multimedia content to enhancing experiences in virtual reality (VR).