[MPlayer-DOCS] CVS: main/DOCS/xml/en mencoder.xml,1.39,1.40

[Diego Biurrun]

On Fri, Apr 01, 2005 at 10:43:40AM +0200, Guillaume Poirier wrote:
> 
> On Apr 1, 2005 10:16 AM, Diego Biurrun <diego at biurrun.de> wrote:
> > On Fri, Apr 01, 2005 at 09:53:10AM +0200, Guillaume Poirier wrote:
> > >
> > > Would it be clearer if I had written:
> > > Please note that MEncoder currently can't currently mux Ogg Vorbis files
> > > into a video stream because it only supports AVI and MPEG containers.
> > 
> > No, not at all.  Again, don't confuse Ogg with Vorbis in the docs or the
> > distinction will never become clear.  You can mux different video and
> > audio streams into a container, but not a container into another (in
> > theory you can, but this is a VERY bad idea).  Thus you cannot mux Ogg
> > (a container) into AVI or MPEG (other containers).  It _is_ possible to
> > put Vorbis audio into AVI, but IIRC MEncoder does not support it out of
> > the box and IIRC AVI does not handle VBR audio well.  The sentence does
> > not make sense, please replace it completely.
> 
> Ok. Thanks for the explanation. I guess I never bothered to really
> understand the distinction between Ogg and Vorbis.
> 
> New sentence:
> Please note that MEncoder currently can't currently mux Vorbis audio
> tracks into the output video stream because it only supports AVI and
> MPEG containers, each of which leads to audio/video synchronization
> problems with VBR audio streams such as Vorbis.
> 
> Or:
> Please note that MEncoder currently can't currently mux Vorbis audio
> tracks into the output video stream because it only supports AVI and
> MPEG containers, which are incompatible with VBR audio streams such as
> Vorbis.

NO!

You have the concepts of streams and muxing wrong.  Audio and video
streams (possibly along with other data like subtitles or whatever)
get muxed (multiplexed) into container (file) formats.  The containers
are demuxed (demultiplexed) to extract their contents, namely audio,
video, subtitle, whatever streams.

So a Vorbis audio track cannot be muxed into an output video stream.
Instead, a Vorbis audio track can be muxed into e.g. a Matroska
container side by side with a video stream.

http://en.wikipedia.org/wiki/Multiplexer

> Ok. Thanks for checking. May I ask you to give me the the URL where
> you found that information? Is that just
> http://www.docbook.org/tdg/en/html/equation.html ?
> Are all the tags documented on that document available for MPlayer's
> XML docs, or should I limit myself to a certain subset of them?

I have the DocBook book from O'Reilly, which is available online from
the URL you mentioned.

Diego