[xiph-rtp] Codebook delivery and metadata

[Michael Smith]

On Thursday 28 October 2004 01:18, Tor-Einar Jarnbjo wrote:

> >Can the chaining module read-ahead (or use the track length) to
> >schedule sending the codebook change message at the right time?
>
> Can we
>
> >accurately pin the codebook change time?
>
> This depends greatly on the data source. The RTP transmitter running
> on j-ogg.de is e.g. only acting as a RTP proxy to a the HTTP stream
> from Virgin Radio. It is of course doable to cache 30 or 60 seconds
> of the HTTP stream to be able to send codebook-change messages in
> advance, but I can think of several reasons, why a radio broadcaster
> is not interested in such a delay for the transmission. Client-side
> buffering is also an issue, at least for mobile units without too
> much memory.

I suspect that, in practice, codebooks won't ever change midstream when doing 
'live streaming' - i.e. radio, etc. I might be wrong, though.

If that's the case, caching the stream isn't particularly troublesome at all - 
it doesn't need to be done for live streams, and for non-live material, a 
delay is unlikely to be a significant problem.

Mike