The pressure you apply on the key is translated by the keyboard (not all
keyboards, mind you) into polyphonic aftertouch events, each encoding both key
number and key pressure.

Use of poly AT events may be one way to achieve what you want : transmit
duration information (or any other info for that matter) when the key is pressed.

One way to implement a MIDI sound generator capable to understand "instant"
note duration might be to store the velocity from the noteon event (for
amplitude control) and start generating the note only at the first poly AT
event referencing the same note number, using pressure as a duration control.
And ignore subsequent poly AT events as well as the noteoff event for said
note number until next noteon.

Or use velocity for duration and poly AT for amplitude : with some imagination
I am sure there are lots of things you can do with MIDI keyboards, and with
MIDI in general.

I have no idea whether such a contraption would be practical from a player's
point of view though (anybody ? I don't play keyboards myself :-).


Paul Barton-Davis wrote:
> 
> >> >> i don't see how any real-time event stream can even supply note
> >> >> duration ...
> >
> >well, one could use polyphonic aftertouch for example, with keyboards which
> >transmit this event.
> 
> i don't get it. i press a noteOn button of some sort. the noteOn is
> delivered to Csound. where's the duration information ?

-- 
Greetings,
Michel
.........................................................................
  Michel Jullian   Directeur General             email mj@exbang.com
  Exbang Industries S.A.
  Mas Chauvain   route de Villeneuve             tel +33(0) 499 529 878
  Maurin     34970 Lattes     France             fax +33(0) 499 529 879

Cquential Csounders:
	the problem is that would have to know the duration of the note
right at the beginning of the note. From the standpiont of real-time
(read that: human) performance, this seems pretty impractical, except
maybe for certain percussion voices.

Cheers,
Mark Vigorito
mtv@u.arizona.edu

On Wed, 28 Jul 1999, Michel Jullian wrote:

> [...]
> One way to implement a MIDI sound generator capable to understand "instant"
> note duration might be to store the velocity from the noteon event (for
> amplitude control) and start generating the note only at the first poly AT
> event referencing the same note number, using pressure as a duration control.
> And ignore subsequent poly AT events as well as the noteoff event for said
> note number until next noteon.
> [...]