SoundScape Renderer

SSR logo

The SoundScape Renderer (SSR) is a tool for real-time spatial audio reproduction providing a variety of rendering algorithms, e.g. Wave Field Synthesis, Higher-Order Ambisonics and binaural techniques. The SSR is currently available for Linux and Mac OS X and has been released as open source software under the GNU General Public License (GPL). It was developed at the Quality and Usability Lab at TU Berlin (http://qu.tu-berlin.de/) and is now further developed at the Institut für Nachrichtentechnik at Universität Rostock (http://www.int.uni-rostock.de/).

You can get the SSR at the Download Page.

If you have questions/comments/suggestions/praise/etc. you can post to the Mailing List or contact us directly via ssr@spatialaudio.net.

Rendering Modules

Several rendering modules are currently available:

  • Wave Field Synthesis (WFS)
  • Vector Base Amplitude Panning (VBAP)
  • Ambisonics Amplitude Panning
  • Near-field-corrected Higher-Order Ambisonics (NFC-HOA – still quite experimental!)
  • (Dynamic) Binaural Synthesis
  • (Dynamic) Binaural Room Synthesis (BRS)
  • … and others

New rendering algorithms can be implemented quite easily using the SSR framework.

Interfaces

Interaction with the SSR can happen either using its Graphical User Interface (written in Qt4) or its network interface (based on TCP/IP sockets). The latter allows for connecting any interface of your choice to SSR. An example for such interfaces is our Android Client (watch the video: http://vimeo.com/17159650).

mozart_full_muted_wfs

The Qt GUI of the SSR in “WFS” mode

mozart_full_muted_binaural

The Qt GUI of the SSR in “binaural” mode

Software Architecture

The SSR is written in C++ under massive use of the Standard Template Library (STL). It can be compiled with g++ (the GNU C++ compiler) or clang++ (the LLVM C++ compiler) and runs under Linux and Mac OS X. For Mac OS X, we also provide a pre-compiled Application Bundle. The JACK Audio Connection Kit is used to handle audio data which makes it very easy to connect several audio processing programs to each other and to the hardware. This way any program that produces audio data (and supports the JACK) and any live input from the audio hardware can be connected to the SSR and can serve as source input.

Since version 0.4.0, the SSR can use multiple threads for audio processing and therefore better utilize multi-processor and multi-core computers. The signal processing core of the SSR was factored out into a separate project called Audio Processing Framework (APF). More information is available in a paper presented at the Linux Audio Conference 2012.

Head Tracking

Binaural resynthesis works best with head tracking. Therefore, the binaural renderers of the SSR have built-in support for the following tracking devices:

  • Razor AHRS, a high-quality, low-cost, do-it-yourself tracker solution with USB and/or Bluetooth support. Open Source firmware and documentation is available at https://github.com/ptrbrtz/razor-9dof-ahrs/.
  • Polhemus Fastrak, which works out-of-the-box (but is not so cheap).
  • InterSense InertiaCube3 (and maybe other InterSense trackers), which needs a proprietary library from their website (and is also not so cheap). Due to licensing terms, we cannot provide InterSense support in the MacOSX AppBundle, you have to compile it on your own.
  • Any tracker which is supported by the Virtual Reality Peripheral Network (VRPN).

Literature

There are a few papers about the SSR available, if you use the SSR in a scientific context, please consider citing one of them.

This ist the most recent paper about the SSR in general:

Matthias Geier, Sascha Spors:
Spatial Audio Reproduction with the SoundScape Renderer
27th Tonmeistertagung – VDT International Convention, 2012
PDF

This paper is about the signal processing core of the SSR and how multi-threading is achieved:

Matthias Geier, Torben Hohn, Sascha Spors:
An Open Source C++ Framework for Multithreaded Realtime Multichannel Audio Applications
Linux Audio Conference, 2012
PDF video

Here we show how the SSR can be used in the background with a custom GUI for psychoacoustic experiments:

Matthias Geier, Sascha Spors:
Conducting Psychoacoustic Experiments with the SoundScape Renderer
9. ITG Fachtagung Sprachkommunikation, 2010
PDF

One of the first papers about the SSR:

Matthias Geier, Jens Ahrens, Sascha Spors:
The SoundScape Renderer: A Unified Spatial Audio Reproduction Framework for Arbitrary Rendering Methods
124th Convention of the Audio Engineering Society, 2008
PDF

Links

Downloads: http://spatialaudio.net/ssr/download/

Development pages: http://github.com/SoundScapeRenderer/ssr/

Wiki: http://github.com/SoundScapeRenderer/ssr/wiki/

Mailing List: https://groups.google.com/forum/#!forum/SoundScapeRenderer

SSR Remote for Android: https://github.com/SoundScapeRenderer/android-remote/

Blog: http://spatialaudio.net/

Old Links

These are links to old versions of the SSR:

http://tu-berlin.de/?id=ssr
https://dev.qu.tu-berlin.de/projects/ssr/wiki/
https://dev.qu.tu-berlin.de/projects/ssr/files/

License

GNU General Public License (GPL) version 3 or higher.

Copyright (c) 2014 Institut für Nachrichtentechnik, Universität Rostock
Copyright (c) 2012 Quality & Usability Lab, Deutsche Telekom Laboratories, TU Berlin