[Speex-dev] [Vorbis-dev] Vorbis-/Speex-Audio for Movie-Archiving

[xiphmont at xiph.org]

> I) Multi-channel
>
> Up until now I mostly encoded to stereo; now I am thinking of encoding more
> movies to 4.0 or 5.1. I heard that vorbis does not optimize for channels > 2,
> i.e. that 6 channels is just stereo*3. AAC is supposed to do this better...
> Now I really digg vorbis, because its patent-free and grass-roots-developed ;)
> so this doesnt mean I am switching to aac, but I'd like to know whether this
> true or if its just FUD.

Vorbis the format is able to efficiently encode multichannel.  The
current encoder does not-- mainly because we've never had access to
high quality surround source to do the tuning.  Starting from another
compressed source, especially a source that's not particularly high
quality to start with like a consumer DVD, is better than nothing, but
not a great solution.

Monty