Re: [linux-audio-user] Blue snoball USB mic

On Thu, 2006-03-16 at 12:25 -0500, Paul Davis wrote:
> On Thu, 2006-03-16 at 17:49 +0100, Lars Luthman wrote:
> > On Thu, 2006-03-16 at 11:45 -0500, Paul Davis wrote:
> > >
> > > jackd -d alsa -P hw:N -C hw:!N
> >
> > Ah, I thought I remembered something like that. That would work great
> > for me, the only thing I have plugged into the inputs on my soundcard is
> > the sound from my TV card, and I usually don't want to record from that
> > using JACK. How does it work internally? If one of the devices has a
> > clock that is slightly slower than the other, will jackd resample the
> > signal to make it as smooth as possible? Or will there be
> > discontinuities when jackd has to skip forward or backward in one of the
> > streams to catch up with the other?
>
> jackd never skips in this way. there will be xruns that will grow worse
> and more frequent as the two devices drift out of sync, and therefore
> are not "ready" at the same time. whichever is ready first won't be
> "serviced" by jackd until the other one is.

I knew that normal JACK clients work like that, but I wasn't sure what
was going on inside the ALSA driver. I guess this means that I need a
separate client that reads from the ALSA input device and outputs the
data to a JACK output, resampled to match the rate JACK is running at?
Are there any clients that do this? I've read about jack_diplomat, but
running a second jackd just to get the data from the input device seems
like overkill.

-- 
Lars Luthman
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