[vorbis] VBR vs ABR

Graham Mitchell graham at grahammitchell.com
Tue Apr 29 12:19:18 PDT 2003



> It seems I have the choice between 
> VBR and ABR formatted oggs.  I am familiar with VBR (variable bit 
> rate) but not sure what ABR stands for?

ABR stands for "average bit rate", which is essentially a constant bit rate,
but using a bit reservoir.

> Is it possible/desirable to specify a bit rate when encoding oggs, 
> or does the nature of the ogg format make use of varying bit rates?

Ogg is inherently VBR, but it has an ABR-like mode.  ABR *always* has worse
sound quality for a given file size than VBR, but the bit rate is a little
more consistent, which is important for streaming folks.

Unless you're planning on streaming, use VBR.

For more details, you can read my intro to vorbis, especially the section
about halfway down called "CBR? VBR? ABR?"
    http://grahammitchell.com/writings/vorbis_intro.html


-- 
Graham Mitchell - computer science teacher, Leander High School

--- >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.




More information about the Vorbis mailing list