Modular Room Simulation for the IVES 3D Engine

Abstract

IVES (Interactive Virtual Environment System) is a modular open-source 3D engine for creating virtual worlds in the Max programming environment. It is intended both for artists to create 3D audiovisual compositions and for researchers to use as a basis for prototyping new algorithms or experimental setups. IVES is based on Max's OpenGL implementation Jitter and IRCAM's spatial audio library Spat. This paper presents the latest development, a room simulation for IVES's parametric rendering. It consists of Spat's Feedback-Delay Network (FDN) for late reflections, accompanied by an Image-Source Model (ISM) module for early reflections and a generator for designing rooms. Here, the geometric parameters of the desired rooms are determined, and material properties are assigned to reflective surfaces. This results in parameters for reflective surfaces, filters, and attenuation for the ISM module and frequency band-specific RT 60 times for the reverberation module using the FDN. The mirror image sources generated by the ISM are fed into the subsequent parametric rendering chain as additional sound sources, and late reverberation from the FDN reverberation module is added to the encoded sound field as spherical harmonic coefficients. We describe the underlying concept and technical implementation, and the possibilities resulting from the open and modular implementation.