[vorbis] Ogg Vorbis v1.1 suggestion

[Carsten Haese]

On Mon, 2003-11-17 at 15:58, Ross Levis wrote:
> My wish for 1.1 is to stream my station with VBR at bitrates averaging
> 28-32kb/s with a minimum 32khz sample rate.  Hopefully this will be
> achievable with the new low bitrate tuning that is planned.  This could
> put it on a par with Real Audio at 32kb/s.  Currently a quality of -1,
> 32khz sample rate produces an average around 34-38kb/s which is too high
> for modems.  I could currently use a managed bitrate but this doesn't
> sound the best and takes too much CPU.  Hopefully this will be addressed
> as well.

On the few files that I have in .wav here, I get quite respectable
results with oggenc --advanced-encode-option lowpass_frequency=12
--resample 32000 -b 40 -M 32. I have no idea how this stacks up against
Real Audio since I don't have that available. Of course, the CPU hit is
still there.

If CPU usage is critical, you could try piping the output of unmanaged
-q -1 into a "peeler" that will throw away the ends of packets that
would go above 32kbps. However, such a peeler does not exist, so you'd
have to try to adapt Segher's peeler to that task, and I have no idea
how feasible that is. Note also that this is roughly how RC3 attempted
to do bitrate management, and Monty said it sucked. However, there is a
chance that you are slightly less demanding than Monty :)

Monty has lots of ideas for Vorbis 1.1, so it's quite likely that it'll
make streaming of 32KHz stereo data at 32kbps easier, but Vorbis 1.1
won't come out for months.

Hope this helps,

Carsten.

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