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

Rob D rddone at att.net
Thu Jan 30 05:17:00 PST 2003



Even if you want a buffer for less time, you may be out of luck.
In windows, the OS/sound card caches 2-3 seconds of music when you send WAV
data to the card.

The sound starts nearly immediately when you send it the first PCM packet,
but the OS/driver accepts several seconds worth of data before it waits to
return.

There may be a way to tell windows to use a smaller (.25 seconds or so)
buffer, and let the player buffer the data in a way to allow nearly
immediate EQ/volume control, but I am unaware.

Rob D

-----Original Message-----
From: owner-vorbis-dev at xiph.org [mailto:owner-vorbis-dev at xiph.org]On
Behalf Of Geoff Shang
Sent: Thursday, January 30, 2003 3:52 AM
To: vorbis-dev at xiph.org
Subject: Re: AW: [vorbis-dev] PlusV algorithm -> CBR

<p>On Wed, 29 Jan 2003, Hannes wrote:

> I know it would mean a great deal of damage to vorbis quality, but would
it
> 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.

Most players have a much bigger buffer than 2 seconds.  Even some testing
I've done with MP3 and mpg123 tends to produce latency of at least 1
second.  Vorbis is not a low-latency codec, like it or not.  I can't
remember the exact figure, but there's a delay that vorbis can not go
below.  that's just fact.  It's the nature of the beast.

Geoff.

<p>--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'vorbis-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.



More information about the Vorbis-dev mailing list