[MPlayer-users] Re: Mplayer/ogm/ogg

[Christian HJ Wiesner]

gabor wrote:

> i'm just curious....
> what's the advantage of having 6channel-vorbis instead of ac3?
> smaller size for same quality?

It should be possible to use Vorbis 5.1 at bitrates of 140 - 180 kbps 
with decent quality. Its not to be seen as an alternative to AC3, but 
more like a good replacement of DPL/DPL2 encoded Stereo streams.


> and that 6channel-vorbis: it's encoded as 3 stereo channels, or does it
> encode intelligently? something like encode the basic info + the 6
> differences?  gabor

Unfortunately not yet :-(

Some Doom9 Forum members had provided Monty with a number of 5.1 FLAC 
samples with critical sound passages so he could start to develop a good 
5.1 channel coupling encoding profile, but he had no time as he was busy 
bringing Vorbis to 1.0 and now is working on Ogg Theora container 
implementation.

On Windows we had plans to make a DShow filter making real time encoding 
to AC3 640 kbps from the Vorbis 5.1 tracks, so we could use external 
Dolby surround receivers via SPDIF out ... i heard this is already 
avaialble for Linux, but cant remember if it was Mplayer or another 
project ...


ChristianHJW
http://matroska.org