[linux-audio-user] Audio interface full duplex

[Frank Barknecht]

Hallo,
Konrad Mathieu hat gesagt: // Konrad Mathieu wrote:

> We are planning to build a system that can send (serve) and receive
> mp3 streams at the same time using a multi channel interface such as
> an RME Hammerfall card.
> 
> As I have about ten boxes running different flavours of linux but
> never even touched a graphical interface, I have gotten as far as
> running mplayer to receive one stereo feed and send it to an M-Audio
> Delta 44 from command line. 
> 
> I wonder if a) you can run several instances of mplayer and send
> their signals to separate outputs of the same I/O card and 

It's possible to do this, either using ALSA's plugin configuration or,
which may be easier, using jack, or better yet ... see below.

> b) whether it's possible to run multiple shoutcast servers at the
> same time that get their audio from the inputs of that same card.

I don't know much about shoutcast, people tend to prefer icecast2
nowadays. An icecast server doesn't connect directly to the soundcard
itself, you use a seperate client software to send audio data to the
icecast server (called the "source client") or read an icecast stream
and play it on a soundcard (the "listening client"). You can use
multiple source and listening clients at the same time, that's most of
the fun with streaming.

See http://www.icecast.org/docs/icecast-2.3.1/icecast2_basicsetup.html
for more details.

You can use different clients for recording from different
combinations of the soundcard's channels as well, again either using
ALSA's plugins or jackd. 

Alternatively you can also use one source client, that can read from
all channels at once and generates different streams to send to the
icecast server.  One software, that can do this, is the almighty Pure
Data which you can use to read streams from an icecast2-server as
well, so it would be an all in one solution to your task (and you can
control it remotely using midi or networking as well, build custom
GUIs etc...)

Pd is, what I would use.

Ciao
-- 
 Frank Barknecht                 _ ______footils.org_ __goto10.org__