[vorbis] Re: mp3PRO encoder/decoder demo available

[volsung at asu.edu]

On Thu, 14 Jun 2001, Paulo [iso-8859-1] Rebêlo wrote:

> 
> >Since Vorbis currently sounds better then MP3 at 128kbps even though
> >it's not using joint-stereo I think that with JS, Vorbis at 96kbps will
> >sound just as good as 128kbps MP3. I bet that the low-bitrate optimized
> >Vorbis will sound as good as mp3PRO at any bitrate (or damn near at
> -- xx --
> 
> Hi,
> 
> I tried to get in touch with Vorbis creators- without success. I'm writing 
> a piece about Vorbis and I know this is a dumb question but, please, could 
> anyone explain me:
> 
> What practical difference does joint-stereo in a music file?

The short version is this:  Most music has very similar audio in the left and
right channels.  Currently, Vorbis encodes the left channel and the right
channel independently.  Joint-stereo encoding (as done by MP3 and many other
compression formats) exploits the similarity between the left and right
channel to compress the audio more than would be possible if the left and
right channel were considered separately.  The result is a smaller file with
the same quality as before.  In practice, this means less bandwidth needed for
your audio or better quality audio given your bandwidth limitations.

Does someone here know how much savings on average you can get with
joint-stereo?


---
Stan Seibert

--- >8 ----
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