[LAD] making sense of Jack MIDI; or, is this an appropriate use for Jack?

M Donalies ingeniousnebbish at cox.net
Fri Feb 15 20:45:02 UTC 2013

On Friday 15 February 2013 13:19:57 J. Liles wrote:
> It means that you have to do that tricky 'sequencing' part, which consists
> of scheduling (MIDI) events and only placing them onto the JACK buffer at
> the appropriate instant. ALSA MIDI does this for you, as well as providing
> a nice API for generating the MIDI events. That's not the trickiest part
> though, the real mess begins when you want to deal with the JACK
> Transport/Timebase API to follow or generate tempo changes.

So there's no way to tell Jack to deliver the event at time t? You have to 
wait for the right frame and then put on the buffer (presumably to appear on 
the buffer for the receiver to use the next frame)?

Unless you mean something other than conversions to/from nanoseconds (or 
whatever), the tempo stuff doesn't much concern me. That's a straight-forward 
number-crunching algorithm. That kind of thing I can do.


More information about the Linux-audio-dev mailing list