[MPlayer-dev-eng] [PATCH] Online audio stream switching

[Michael Behrisch]

On Sun, Feb 27, 2005 at 02:27:50PM -0500, D Richard Felker III wrote:
> On Sun, Feb 27, 2005 at 08:03:16PM +0100, Michael Behrisch wrote:
> > On Thu, Feb 24, 2005 at 07:01:14PM +0100, Michael Behrisch wrote:
> > > The attached patch enables audio stream switching
> > > in the mpg demuxer using the #-key. It is not complete yet,
> > > because manpage is not updated, but I wanted to get some
> > > opinions before doing the really hard work ;-)
> > 
> > OK here we go. This patch lets you instantly switch from german to english
> > on your favorite dvd to hear the original version of that four letter word.
> > 
> > A single keypress instead of stopping, looking for the right aid and 
> > restarting and searching over and over again. (It works only if both audio 
> > streams have the same format, but it works.) And it can also walk your dog.
> 
> A single keypress will make it horribly crash unless the new audio
> track has exactly the same codec and format as the old one. This is
> very bad. Consider DVDs that have some tracks as 2.0 AC3 and others as
> 5.1 AC3, or a mix of AC3, PCM, and DTS. Unless you work out all the
> mess to close down and reinitialize the audio layer for the newly
> selected audio track, a patch like this (which only works on a very
> limited number of files and crashes on all the rest) is not
> acceptable. I know it's very hard to do this right (that's why no one
> has done it yet..) but that's the way it is. Sorry..
> 

Well, the patch already knows about the difference between AC3, PCM and DTS
and switches only between streams of the same format. Switching
between 2.0 AC3 and 5.1 AC3 did not make problems here but please
send me a sample where it does.

Michael