Efficient acoustic radiance transfer method with time-dependent reflections

Abstract

Modern desktop computers are equipped with graphics cards that provide massive parallel computation power that was previously available only in supercomputers. On the other hand, there are several room acoustics modeling methods, but only some of them scale well to hundreds or thousands of parallel processors. The scalability of the acoustic radiance transfer method is examined. It is shown that it can almost fully utilize the available computing power. In simple cases, this technique achieves real-time performance. While taking into account the limitations of the energy-based acoustic modeling approach, the presented system can model arbitrary reflections. The directionally-dependent reflections are presented as bi-directional reflectance distribution functions which depend on the incoming and outgoing directions of acoustic energy. It is also possible to add time-dimension to such a reflection model. Some measurements are presented to show that spreading in time dimension occurs at reflections. Most of the previous room acoustic modeling techniques have ignored that phenomenon, but the acoustic radiance transfer technique can be easily modified to take it into account. © 2011 Acoustical Society of America.