[Vorbis-dev] Ambisonics in Vorbis

[Martin Leese]

On the Ambisonics mailing list
"Oliver Thuns" <oliver.thuns+ml08  gmail.com> wrote:

> I found this on the AES Amsterdam website:
>
> P9-2 Encoding Higher Order Ambisonics with AAC?Erik Hellerud,
> Norwegian University of Science and Technology - Trondheim, Norway;
> Ian Burnett, University of Wollongong - Wollongong, New South Wales,
> Australia; Audun Solvang, U. Peter Svensson, Norwegian University of
> Science and Technology - Trondheim, Norway
> In this paper we explore a simple method for reducing the bit rate
> needed for transmitting and storing Higher Order Ambisonics (HOA). The
> HOA B-format signals are simply encoded using Advanced Audio Coding
> (AAC) as if they were individual mono signals. Wave field simulations
> show that by allocating more bits to the lower order signals than the
> higher the resulting error is very low in the sweet spot but increases
> as function of distance from the center. Encoding the higher order
> signals with a low bit rate does not lead to a reduced audio quality.
> The spatial information is improved when higher-order channels are
> included, even if these are encoded with a low bit rate.
> Convention Paper 7366

This reminded me that Ambisonics support is
being developed for Vorbis.  It would be a
shame if the proprietary people got there first.

Regards,
Martin
-- 
Martin J Leese
E-mail: martin.leese stanfordalumni.org
Web: http://members.tripod.com/martin_leese/