AW: [vorbis-dev] PlusV algorithm -> CBR

[gtgbr at gmx.net]

Hannes wrote:
> >> 2) CBR encoding
> >window. An oggenc command line would look like `oggenc --managed -m
> ><bitrate> -b <bitrate> -M <bitrate> input.wav`. I'm not quite sure why
> >you'd want this, though - quality suffers and CBR is only required in
> >pretty exotic environments.

> If you consider a streaming application an exotic environment, OK.
> Personally, I don't.

I don't, and CBR is not necessary for streaming either. For broadband
listeners, quality mode works great (i sometimes stream stuff to my
friends, I have 128kbps upstream and -q 1.5 is just fine). If you need
more control, using the bitrate management engine without the -m and -M
limiters gives you a pretty constant stream already that is useable for
ISDN/56k modem users. If you have to go really low and every kbit too
much hurts, the -M limiter is alright. Every clientside buffer for such
low bitrates is big enough to hold much more than two seconds. And if
everything fails, use the advanced options.

> really be so bad considering the possibilities? And if, how big would the
> bandwidth adaptation window really have to be - 2 seconds? thats about 1.9
> seconds too long, if this adds on my streaming latency, sorry.

Vorbis is not designed for low latency. And as Dan Miller pointed out,
Vorbis simply doesn't work in truly exotic environments. Exotic from my
point of view, at least. Maybe it works on some with really harsh
settings, but who knows ...

<p>Moritz

P.S.: Have you checked out whether you prefer 22.5kHz or 32kHz over
44.1kHz/mono for your stream? Have you tried -M 56 to hard-limit the
stream? (The 2-seconds window really doesn't hurt, even if it exceeds
64kbps for a few milliseconds)
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