[ogg-dev] OggPCM proposal feedback

Arc arc at Xiph.org
Thu Nov 10 08:42:22 PST 2005

On Thu, Nov 10, 2005 at 05:30:10PM +0100, oliver oli wrote:
> John Koleszar wrote:
> >I hadn't even heard 
> >of ambisonics until your post, to be honest.
> because people don't know how to distribute ambisonics. no way to play 
> it in a DVD player. there are no easy to use software players that 
> decode ambisonic files and there are no widely used audio file formats 
> that support ambisonics (you can store 4 channel in many audio file 
> formats, but it's not tagged as ambisonics). Apple's CAF is the only 
> format I know of that supports ambisonics (4channel B-Format only).

That is a reason for us to proactivly support it.  Especially if this is true:

 "The Ogg Vorbis project has shown interest in implementing ambisonics as a 
  means for including surround sound in their project."

>From the wiki, it seems to be only 4 channels, not more, even though you may 
have many more speakers.  I don't know how this "WXYZ" data is setup, if XYZ are 
just other audio channels which can be handled the same way or if they need to 
be treated special..

Big question I have is: Is it patent-clear?  Trademark-clear?  There is a patent 
by Michael Gerzon on the tetrahedral array (soundfield) microphone, but which 
software patents exist for the system itself needs to be investigated further.


The recognition of individual possibility,
 to allow each to be what she and he can be,
  rests inherently upon the availability of knowledge;
 The perpetuation of ignorance is the beginning of slavery.

from "Die Gedanken Sind Frei": Free Software and the Struggle for Free Thought
 by Eben Moglen, General council of the Free Software Foundation

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