Reverberation-Time Prediction Method for Room Impulse Responses Simulated with the Image-Source Model

Abstract

The image-source method has become a ubiquitous tool in many fields of acoustics and signal processing. A technique was recently proposed to predict the energy decay (energy-time curve) in room impulse responses simulated using the image-source model. The present paper demonstrates how this technique can be efficiently used to determine the enclosure's absorption coefficients in order to achieve a desired reverberation level, even with a non-uniform distribution of the sound absorption in the room. As shown in this work, classical expressions for the prediction of an enclosure's reverberation time, such as Sabine and Eyring's formulae, do not provide accurate results when used in conjunction with the image method. The proposed approach hence ensures that the image-source model effectively generates impulse responses with a proper reverberation time, which is of particular importance, for instance, for the purpose of assessing the performance of audio signal processing algorithms operating in reverberant conditions.