Re: [Denemo-devel] Portaudio

[Richard Shann]

On Fri, 2009-02-13 at 13:17 +0100, Nils Gey wrote:
> > > Will it be replaced by a generic JACK-in some day?
> > I don't yet really understand what JACK-in is. What we have at the
> > moment in Denemo (I think) is jack-midi in, which would not perform the
> > same functions. I say, "I think" because it is not yet in my Debian
> > distribution, so I have not yet had a chance to try it.
> > 
> > Richard
> 
> Jack is not in the Distribution?
Jack is, no jack-midi though.
>  Its called the jack-audio-connection-kit sometimes. This is really a 
> standard package.
> 
> Basically Jack is for Audio what Jackmidi is for midi. You can route your 
> audio latency-free from any application to any.
Ah, right, I think I get that - so instead of saying "open me a port and
callback here when you want pcm samples of 16bit ints at 44000 samples
per second" as you do with portaudio, you would say the the same sort of
thing to jack & jack would send the audio on to anything that had
connected to jack and asked for it. Whereas Portaudio only connects to a
soundcard (I guess), albeit cross-platform. ok.

>  Jack is an audio-sever so the plus is you don't rely on drivers (portaudio, 
> alsa etc.) and your program, Denemo, has nothing to do with providing direct 
> audio-support, which is genereally a good thing.
> 
> In this particular case its: Denemo creates a Jack-port on startup, if it 
> finds JACK running, and then you can connect any audio-source (microfon, any 
> other programms) to Denemo and let it process the audio, like checking the 
> pitch.
> The other way around is that Denemo creates a Jack-output and can output its 
> audio-feedback to any destination, the hardware/speakers of course but also 
> recording programs or any other.
> 
> With Jack and Jackmidi Denemo would be completly independent from any driver 
> level and truly crossplatform and opens the way for fancy-future-stuff like 
> adding a sampler/syth right in denemo and distribute it with nice-sounding 
> soundfonts for the instrument (basically take the fluidsynth-lib or any other 
> and integrate it into Denemo)
Thank you, sorry to have been so slow on the uptake, difficult to make
out what is going on without seeing it.
Richard