[MPlayer-users] 2 audio streams [-af export??]

[Mick]

On Tue, 2004-07-06 at 22:08, Jan Knutar wrote:
> > Only, mplayer does not seem to be able to play it.  my guess is this is some
> > kind of fifo??
> 
> The man pages says memory mapped file.
> 
> I don't see any mention ofany  synchronisation mechanism though, so playing
> from it would probably not work very well... :/
> 
> > Then, when I play play audio etc it gets picked up the the background
> > player, and that is then piped out to other sound card..  Does this sound to
> > rediculous??
> 
> You could try experimenting with creating a fifo for use with -ao pcm, and read
> from that. MPlayer will block until someone starts reading from it, afaik. Check
> man page for how to specify file to dump to, and whether you want wav headers
> or not... mkfifo for makinf a fifo.
> 

The problem I see with this is this it puts me in the same position i
was in beofre using a fifo..  From what I'm learning, mplayer is limited
to oe output device.  be its pcm (wave file..) or one sounds card..

So if I output to a pcm file, then i can't output to the sound device as
well.

To make this work for 2 sounds devices, i would need to output to a pcm
fifo, read the fifo to some kind of ring buffer, the have 2 such mplayer
daemons playing off the buffer..

Alls this, and i'd even say i pretty poor at bash scripting.. So it
sounds out of my reach..

> > Does anyone know how to use the export plugin correctly?  The docs tell you
> > how to export, but I can't find anything about importing that data (into
> > anything..)
> 
> You'd need to mmap it into some C program, then you'd basically have an ever
> updating area in memory with audio data, but no way to tell when it has changed
> or if you missed anything :) I think it's basically meant for visualisation apps, where
> audiostream integrity isn't important.
> 
>From the sounds of this trhead:
http://zebra.fh-weingarten.de/~maxi/html/mplayer-dev-eng/2003-11/msg00314.html

Some updates have been made to try to enforce a playable audio stream is
exported..  I guess I'm going a bit far assuming mplayer could read from
its own export stream..

Mick