[vorbis] [new?] Streaming technique

[Aleksandar Dovnikovic]

"Alex Iribarren" <ogg at iribarren.com> wrote:

> The question is, does Ogg use perceptual coding, like mp3 does? And 

Yes Ogg Vorbis is a perceptual codec.

> if so, would it be possible to build an encoder in such a way as 
> to take one input stream and make it produce 2 different files? One 
> file encoded at 64kb, and the other file with the information dropped 
> from the stream that would have made the resulting encoded stream 
> 128kb? What I mean is a way to produce 2 64kb files which could be 
> somehow "added up" on the decoder to produce a 128kb stream. Is there 
> a name for this kind of thing, or have I just made it up?

Ogg Vorbis supports bitrate peeling - thist means that if you have,
for example a 256kbps file, you can create a 128kbps file *without*
re-encoding (decoding to WAV and then encoding again at
128kbps).
I think that this feature doesn't exist in any other codec. :-)

There is no point in having two 64kbps streams, because using
bitrate peeling you can quickly create one 64kbps from 128kbps.

Bitrate peeling should be fully functional in the next release
(I think it already is in the CVS).


---
Aleksandar @ Vorbis Xtreme | http://solair.eunet.yu/~aldov
Ogg Vorbis is the free, open source alternative to MP3

--- >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-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.