Software of Daniele Salvati

HybridRIR

HybridRIR is a MATLAB toolbox for generating controlled, model-based multichannel room impulse responses (RIRs). It implements a hybrid construction in which geometry-dependent early reflections are generated with the image source method (ISM), while late reverberation is synthesized as a bandwise decaying stochastic process with prescribed diffuse-field inter-channel coherence.

The toolbox is intended for controlled analysis and evaluation of microphone-array methods under explicit modeling assumptions. Its main features include:

• Geometry-consistent early reflections using a shoebox-room image source method
• Bandwise stochastic late reverberation with an isotropic diffuse-field coherence target
• Multichannel late-field synthesis through bandwise Cholesky coloring
• Automatic reverberation-time calibration by bracketed bisection on the assembled response
• Wall reflection coefficients initialized from the Eyring-Norris relation
• Broadband reverberation-time estimation from octave-band T30 values, with T20 fallback
• Multichannel receiver arrays with arbitrary microphone positions

Requirements: MATLAB R2025a or later, Audio Toolbox, and Signal Processing Toolbox. The toolbox is released under the MIT License.

The source code, documentation, and usage examples are available at:

• GitHub repository
• MATLAB Central File Exchange

HybridRIR is the companion code of the following paper:

D. Salvati, Hybrid multichannel room impulse response generation with joint reverberation-time and diffuse-field coherence control, IEEE Transactions on Audio, Speech and Language Processing, Volume 34, Pages 4173-4188, 2026.
DOI: 10.1109/TASLPRO.2026.3727932