[vorbis-dev] Ogg Vorbis Framing

[Monty]

> Here are some thoughts on Vorbis framing, which may make it easier to
> stream Vorbis in real time.  The suggested changes also move more audio data
> closer to the beginning of each page.

You've confused 'pages' and 'packets' throughout your suggestion.  Your
understanding (or at least description) of how things work is too muddled to
really critique; the description is incorrect at most important points.

A few things to help you go back and look it over again:

a) pages and packets are *not* the same thing
b) you don't truncate *pages*; you truncate *packets* 
c) Ogg format is a frozen stream format meant for storage, local playback and
lossless, noninteractive tranmission.  It is not used for lossy net broadcast; 
we map to RTP/RTSP for that.
d) pages and headers are seperate abstractions; pages layer over formless 
packet data.  We do *not* mix the data.  KISS, thus the header is self contained, not shot throughout the page.
e) CRC is absolutely essential to page capture.  It's not something you can
take or leave.  You have to have a whole page to compute it regardless.
f)lacing-> packet is not 1 to 1, the same as pages do not necessarily hold integral packets, etc.  Pages are a capture and marking mechanism only.

> Is anyone else out there looking at a Vorbis ASIC?  I guess a response to this particular
> question really belongs in the 'user mailing list'.

Actually, a member of OSDN showed us a completed FPGA design yesterday at
linuxworld, which they're taking to custom VLSI.  He plans to post the complete
plans.

Monty

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