1 / 12

Creating True 3D Spatial Audio Systems with Consumer Hardware and Open-Source Software

This work demonstrates how inexpensive consumer-level hardware can be used, alongside open-source software for Linux, to establish a true 3D spatial audio system. Unlike typical planar configurations constrained to surround sound, our method allows for comprehensive audio experiences with sound perceived from all directions. Utilizing setups like the Mustajuuri API and ALSA drivers, we detail the necessary hardware and software configurations and present tests conducted in immersive virtual reality environments, illustrating significant improvements in audio localization and quality.

adelio
Télécharger la présentation

Creating True 3D Spatial Audio Systems with Consumer Hardware and Open-Source Software

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Abstract Current audio solutions for PCs provide sound panning only in a planar configuration. Therefore, drivers for these sound cards do not support non-planar configurations. Systems that are developed for 3D spatial audio are geared for the professional user market and are very expensive. Our work explains how to use inexpensive consumer-level hardware and open-source software for Linux to build a true 3D spatial audio system.

  2. Introduction • Typical speaker configurations: 4.1, 5.1, and 7.1 • It is not possible to have sound emitted from above or below the listener, it is only possible to simulate this effect • True 3D spatial audio allows sound sources to clearly be heard in all directions • Therefore, a sound source from the upper left can be differentiated from a source from the lower left

  3. Background • High-cost hardware packages available for high acoustic quality: • RME Hammerfall • High-end sound card • M-Audio Delta • High-end sound card • Lake Audio • Full sound system (software, speakers, etc.) • Mustajuuri • 3D spatial audio API built upon ALSA drivers • Developed by Tommi Ilmonen at Helsinki University of Technology (HUT) • Implements Vector Base Amplitude Panning (VBAP) as the underlying 3D spatial audio model

  4. Hardware Selection • Used eight speakers in a cubic configuration • Each speaker at a vertex of the cube • Requires a sound card capable of producing eight-channel audio • Such as Creative Labs Audigy 2 ZS card • Ideally, speakers should be able to amplify line-level inputs or separate amplifiers should be used between sound card and speakers • However, this can be done in software, albeit at a lesser quality

  5. Hardware Setup

  6. Software Selection • Primary development under Linux • ALSA driver provides audio and MIDI functionality to Linux OS • Mustajuuri API provides the features needed for 3D positional sound system and is easy to extend

  7. Software Setup • Task 1 – Configuring ALSA: • Necessary to define an “asymmetric” device • Number of input and output channels is not necessarily the same • An environment variable must be set to allow Mustajuuri to talk to the audio card through ALSA • Task 2 – Configuring Mustajuuri Mixer Panel • Configure a mixer-board style GUI • GUI has two mixer strips

  8. Software Setup • Task 3 – Specifying Speaker Placement • Set up the configuration file to specify azimuth and elevation angles for each speaker relative to position of listener • Task 4 – Configuring Sound File Loader • Set up configuration file to specify all sound files possibly used by Mustajuuri • Task 5 – Configuring Mustajuuri for Remote Control • Set up Mustajuuri to listen for control commands over a network • Task 6 – Interfacing with Mustajuuri API • In order to control Mustajuuri from an application, it is necessary to add code included with Mustajuuri API into the application

  9. Hardware Testing and Calibration • Tested hardware by integrating system with a 4-wall immersive virtual reality room • Speakers were arranged in cube array and placed in the corners of the immersive room 4-Wall Immersive Room

  10. Software Testing • Integrated sound in an existing simulation platform operating on a Linux visualization cluster • Tested the sound system by attaching audio effects to animated objects in our scenarios

  11. System Validation • Evaluated how the new sound system configuration compared with previous planar configurations • Used unbiased test subjects • Switched between each configuration and rated audio quality of each system • Every test subject preferred the sound from the new, non-planar system • Evaluated how well the listener is able to localize the source of the audio using the 8-speaker configuration • Presented subjects with several sounds, played one at a time, originating from different positions around the immersive room • Subjects were able to localize the direction of the sound source correctly in all three dimensions.

  12. Conclusions and Future Work • Future: • Directional Sound Cones • Additional Environmental Reverberation Effects • Enhanced Sound Attenuation Model

More Related