[MPlayer-users] Re: using mplayer as a surround decoder (not media player...)

[Amadeus W.M.]

On Fri, 11 Jun 2004 11:35:20 +0100, Darrell Berry wrote:

> Hi
> 
> I'm interested in building a 'blackbox' surround decoder -- s/PDIF in, and
> multichannel surround analog out. No interface, wapping plugs if I want to
> change source/destination...
> 
> I can see that its easy to get surround out when playing MEDIA via
> mplayer, but is there any way to simply use it as a decoder: for it to
> take what comes in on the S/PDIF input, and stream out decoded surround to
> an ALSA soundcard (or if not mplayer, can anyone point me at any other
> alsa-aware software or linux-friendly hardware that can work as a pipeline
> decoder for dts/dolby?)
> 
> And if so, what's the lowest latency I could reasonably expect
> mplayer/alsa/linux to introduce? I'm looking at high-end audiocard/DAC, so
> the card is unlikely to be the major source of signal delays...
> 
> I know there are all-in-one cards that will do all the above, but I'm
> trying to build something quite high-end, and want it modular so I can
> tweak/upgrade individual elements of the box to achieve best
> performance...
> 
> thanks!

You might be able to do it with mplayer, but as an alternative,
you may want to look into gstreamer. I'm not sure if it will do
precisely what you want (although there is a good chance it will),
but it was designed so that you could build pipelines at will, with
various encoders/decoders, plugins, etc. For instance, you can do

gst-launch filesrc location="music.mp3" ! ffdec_mp3 ! filesink
location=osssink

This has 3 elements in the pipe: a file source, an mp3 decoder and a 
sink (there is an alsa sink too).