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<div bgcolor="#FFFFFF" text="#000000">What I want to do,
is to use the resources I have to run multiple signal
generation and processing chains asynchronously, in
parallel, and then use the final
audio-hardware-synchronized chain to resample them all
into one, perhaps using the Zita tools. Anyone know if
this is possible? I saw this flow structure work very
well in the video domain, quite a few years ago.<br>
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<div>That's not what you want to do at all.<br>
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<div>JACK is designed to be a *synchronous* system. All
clients process audio corresponding to the same period of
time, precisely in sync with each other. You do not want
to "resample them all into one", and certainly not with
the zita tools. <br>
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<div>A "correct" digital audio processing and/or synthesis
environment consists of a single audio interface (or at
least, a single digital sample ("word") clock). You can
run any number of JACK clients, connected in arbitrary
ways. But using multiple audio interfaces (which is what
the zita tools are related to) is not the right thing to
do unless you are forced to by lack of funds or
inappropriate hardware.<br>
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I do understand that JACK is designed to be completely synchronous.
But a good pipelined architecture, can take multiple synchronous
processing chains running independently (asynchronously to each
other), and then merge them at the output end. What I want to do is
the equivalent using JACK at the synchronous level, so that I take
advantage of more of my computing power. Eventually I will want to
do exactly the same using four or five RPi-compatibles, with just
one of them having the audio output; but right now I have about 75%
of my CPU and 6+ gigabytes of RAM not being touched, so clearly the
testbed is waiting :-). The video processing pipeline I saw a while
ago used a proprietary bus (it was a while ago), I am thinking IP is
probably the simplest now, over localhost within this box, and
through a good switch whenever I start work on RPis (which is
probably not soon but is worth contemplating).<br>
<br>
And to use the Zita tools, I was going to see if there was an
audio-over-IP transport which delivered ALSA ports :-) I don't
quite remember, it has been about eight months since I looked. If
there is, I would expect the existing Zita tools would do
wonderfully for the resampling connectors. If not, I wonder what
best to use for JACK-to-JACK resampling?<br>
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