tool to add skeleton (was Re: [Vorbis-dev] Re: [ogg-dev] Peer review draft for the new)

[Aaron Colwell]

Ivo Emanuel Gonçalves wrote:
> On 10/3/07, Silvia Pfeiffer <silviapfeiffer1 at gmail.com> wrote:
>> There is actually an I-D that Luca is writing
>> for audio/vorbis at
>> http://www.ietf.org/internet-drafts/draft-ietf-avt-rtp-vorbis-07.txt
> 
> That document states that RTP Vorbis needs a special media type for
> configuration data.  What is this exactly?  Is it really necessary?  I
> never saw RTP payload formats using a configuration-only media type.
> Then again, I only read the draft briefly, so most likely there may be
> a reason to have it.  Doesn't hurt to ask, though.
>

I'm assuming your referring to the audio/vorbis-config type. This is 
used for the packed headers when they are retrieved by out-of-band means
like over HTTP. It is necessary. Other RTP payload formats don't tend to
do this because most(all?) of the existing codecs don't need to send
codebooks for playback. They also don't tend to allow codebook changes
in the middle of the stream. Xiph's philosophy of allowing unique
codebooks for every encode and Ogg's chaining feature make this necessary.

Hope this helps.

Aaron