Re: MIDI NoteOff velocity

From: Eric Scheirer (eds@media.mit.edu)
Date: Wed Sep 01 1999 - 09:54:43 EDT


It is a common misconception that the note-off velocity is
a useful MIDI feature. This is not the case; to quote
directly from the MIDI specification:

   "Some keyboard instruments implement release velocity
    where a Note-Off code accompanied by a 'velocity off'
    byte is used. A receiver must be capable of recognizing
    either method of turning off a note, *and should
    treat them identically.*" (emphasis added)

The SAOL spec treats them identically; that is, as described
in 5.14.3.2.4. There is no way for a SAOL program to access
the noteoff velocities. Content authors who want some
special controller action on note-off should use a controller
just before or synchronous with the note-off; this is the
practice recommended by the authors of the MIDI spec, I
think.

Several of the authors of the MIDI spec helped us write the
MIDI parts of the SA spec. As a result, the spec generally
takes a "hard-line" approach to MIDI rather than a looser
"common practice" approach.

Even aside from this, it's a logical confusion of the roles
of control and note-duration to think of a "release velocity."
A release is a release, and if you want continuous control,
you should use a controller.

You can figure out when the note has been released by looking
at the "released" standard name:

// k-rate

if (released && !extended) {
  extended = 1;
  extend(0.5); // stay on for 1/2 second
  releaseval = MIDIctrl[10];
  ...
}

Best,

 -- Eric
+-----------------+
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-----Original Message-----
From: Michel Jullian <mj@exbang.com>
To: saol-dev list <saol-dev@media.mit.edu>; saol-users list
<saol-users@media.mit.edu>
Date: Wednesday, September 01, 1999 9:25 AM
Subject: MIDI NoteOff velocity

>How does one get the MIDI NoteOff velocity in a MIDI-controlled SAOL
>instrument ?
>
>I can see where to find the noteon velocity (in the second instrument
>parameter), but can't find the noteoff one.
>
>--
>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
>.........................................................................
>



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