Google Announces Omnitone For Spatial Audio Rendering On Web

Google IO 2016 VR Cardboard AH NS

Virtual Reality is gaining popularity at an incredible pace, and soon along with dedicated apps and services, people would want Virtual Reality to work in day to day web surfing and web-apps. Google, as they do, has already started working on the future course of virtual reality, to be prepared when there is more consumer demand in the area. Google has recently announced Omnitone, an open-source software which can be used by integrated into website and web-apps by developers to deliver spatial audio in tandem with the experience of virtual reality.

Google was quick to realize that the current processing of audio, although suitable for surround sound experience with regular screens, is not enough to complement the audiovisual experience of virtual reality. Thus, Omnitone was born. The California-based tech behemoth made use of ambisonics to develop Omnitone. Ambisonics is the technique that allows sound to be simulated as a full sphere in three dimensions around the listener, covering not only the horizontal plane of the sound waves but also above and below the listener.

Google uses location data and other data from a host of sensors present in the Virtual Reality headset to determine the exact spatial coordinates of the listener to adjust the audio sphere with respect to the listener. Following this, the audio data is sent to an emulation of 8 virtual speakers and then mixed down to stereo by another binaural renderer, creating the perfect full sphere surround stereo sound which changes with the movement of the listener. As soon as the listener moves his head, the movement is automatically processed, and the perception of sound changes. All the rendering happens in real time, making it a very immersive experience for the user.


The developer team responsible for Omnitone was faced with a significant difficulty while integrating this feature into the browser without making it resource heavy and cluttered, and using the resources available with WebAudio. The usage of Omnitone helps create a near-perfect soundstage of the source music, depending on the spatial positioning of the listener. The source code is available on GitHub licensed under Apache. Google has also provided two videos featuring spatial audio processed by Omnitone to allow users with VR equipment to be able to experience the difference.

The videos feature musicians in different angles and distances, perfect to determine the soundstage keeping in mind the location of the listener. As the audience rotates and moves, various parts of the audio can be heard loudly or softly, depending on the distance and angle of the listener from the musicians. According to the blog post by Google, this feature will be coming to Chrome for mobiles soon.