The 3D Tune-In Toolkit is a standard C++ library for audio spatialization and simulation of hearing loss and hearing aids.
The 3D Tune-In Toolkit has been developed by teams at the University of Malaga and at Imperial College London, and it has now been released open source with a GPLv3 license (royalty-free for non-commercial use) on the 3D Tune-In GitHub repository.
It includes the following functionalities:
Binaural spatialisation - integrates features such as:
- HRIR convolution based on a standard uniformly partitioned Overlap-Save algorithms.
- HRIR barycentric interpolation approach is used among the three closest available HRIRs.
- The acoustic parallax effect is taken into account; left and right HRIRs are selected independently according to the relative angle between each ear and the sound source.
- ITD is managed separatly from the HRIR, also calculated with barycentric interpolation or customized (computing them for a specific user-inputted head circumference).
- ILD simulation, adding an extra ‘shadow’ in the contralateral ear for near-field sound sources, according to the spherical head model.
- Far-field sources simulation, with a low-pass filter emulating frequency-dependent air absorption.
- Spatial reverberation is simulated in real time, using a uniformly partitioned convolution with BRIRs employing a virtual Ambisonic approach.
- The Toolkit supports different sampling rates and can work with different frame size.
- The Toolkit allows to move not only the sound sources, but also the listener, managing all the required geometric calculations.
Loudspeaker spatialisation - based on 2nd Order Ambisonic encoding and decoding, and it includes convolution-based Ambisonic reverberation.
Hearing loss simulator – integrates features such as:
- Multi-band dynamic range compressor/expander, to emulate the frequency- and level-dependent features of hearing loss.
- Automatic configurator of hearing loss emulation from the user-input audiogram.
- Frequency smearing algorithm, for emulating the broadening of the auditory filters.
- Temporal distortion (jitter), for emulating the decrease in the precision of neural synchronization in the midbrain.
Hearing aid simulator – integrates features such as:
- Dynamic equalization and dynamic range compression/expansion, to compensate for different hearing loss curves at different signal levels.
- Band-pass filtering and re-quantisation (i.e. bitrate reduction), in order to simulate the specific acoustic and AD/DA conversion features of a given hearing aid.
- Directional processing (e.g. omnidirectional, cardioid, etc.).
- Easy-to-access integrated controls for general compression rate and tone control (i.e. control of levels for low, mid and high frequency response).
More information about the 3D Tune-In Toolkit functionalities can be found here.
Online 3D Tune-In Toolkit
3D Tune-In Toolkit Test Apps
The 3D Tune-In Toolkit Test Apps, both for binaural and loudspeaker spatialisation, have now been released. You can now download and install the test apps on your Windows, Mac and Linux computer, and perform real-time binaural and loudspeaker spatialisation with multiple sources, simulating different virtual spaces, and adding in the signal path also the simulation of hearing loss and hearing aids. An updated list of the Test Applications can also be found in the 3D Tune-In GitHub account, in the Releases section.
Each zip package contains a list of features and a manual.
3D Tune-In Toolkit Test App binaural version (BiTA)
ATTENTION – the 3D Tune-In Toolkit Test App for Windows looks first for ASIO drivers, and only if no one is found, it looks for Direct Sound drivers (i.e. the integrated interface on your machine). Therefore if you have installed on your Windows machine an ASIO audio interface, the 3D Tune-In Test App will not be able to use any Direct Sound audio interface. You will therefore need to either remove every ASIO driver from your machine (and in this case the Test App will be able to see the on-board audio interface), or to just use the ASIO interface directly.
3D Tune-In Toolkit Test App binaural resources
Includes HRTFs, BRIRs, anechoic audiofiles, and other resources that could be useful for running the binaural Test App.
3D Tune-In Toolkit Test App loudspeaker version (LoTA)
3D Tune-In Resource Management Package
Includes SOFA files reader, and converter from SOFA to binary 3DTI format - Windows only.
If you are interested in using the 3D Tune-In for commercial purposes, please contact the project coordinator Dr. Lorenzo Picinali (firstname.lastname@example.org) and/or the leader of the development team Dr. Arcadio Reyes-Lecuona (email@example.com).
If you are interested in those, please contact the project coordinator Dr. Lorenzo Picinali (firstname.lastname@example.org) and/or the leader of the development team Dr. Arcadio Reyes-Lecuona (email@example.com).
3D Tune-In Toolkit binaural spatialisation demo.
This is a brief demo of the capabilities of the 3D Tune-In Toolkit in terms of binaural spatialisation, including environmental acoustic and distance simulations. The first audio is the original anechoic recording:
The second one is the actual audio spatialised using the 3D Tune-In Toolkit: