MIDI Note On/Off

MIDI Note On/Off

Post by Andre » Tue, 21 Sep 2004 11:43:32


I have been looking at the internals of
a few monophonic MIDI files and have noticed a few
files that do not contain MIDI off events.
(they were just a series of MIDI on events only)

Does the specification require a MIDI off
event for each MIDI on?

If not, then the note just plays until it
receives another MIDI on?

Thanks,

Andrew
 
 
 

MIDI Note On/Off

Post by Barry Grah » Tue, 21 Sep 2004 13:56:15


The Note Off messages in your file are actually Note On messages with a
velocity of zero which turns the note off. This is common in the output from
many MIDI applications.

 
 
 

MIDI Note On/Off

Post by Jeffery S. » Wed, 22 Sep 2004 02:49:45

On Mon, 20 Sep 2004 14:56:15 +1000, "Barry Graham"





It is also possible that a purely monophonic synth file/controller
would omit the note-off events entirely. This isn't common, because
most MIDI synths are polyphonic, and also, it does no harm to have
note-off events (or note-on with velocity zero, the alternative way to
send a note-off message).

However, this sort of thing is unlikely, unless someone hand-edited
a file, entering only note-on events (and knowing that the synth would
not keep sounding the notes, since a new note-on in a mono channel
cancels the previous note).

--
*-__Jeffery Jones__________| *Starfire* |____________________-*
** Muskego WI Access Channel 14/25 < http://www.yqcomputer.com/ ~jeffsj/mach7/>
*Starfire Design Studio* < http://www.yqcomputer.com/ ;
 
 
 

MIDI Note On/Off

Post by Andre » Sat, 25 Sep 2004 00:01:51

Yes, so some of the files I've been looking
at have a note on with velocity of zero instead
of a note-off event.

Is there any program available to convert these
non-standard files to note-on/note-off files?

I need some consistancy in order to finish my project.

Thanks,

Andrew
 
 
 

MIDI Note On/Off

Post by Michael R. » Sat, 25 Sep 2004 01:55:51


There is nothing non-standard about using NOTE ON w/velocity=0 as a
synonym for NOTE OFF. It is explicitly included in the MIDI spec and
is a good idea because it allows greatly thinning the data stream
via running status when only NOTE ON/OFF events are occurring.

--
========================================================================
Michael Kesti | "And like, one and one don't make
| two, one and one make one."
XXXX@XXXXX.COM | - The Who, Bargain
 
 
 

MIDI Note On/Off

Post by Me » Thu, 30 Sep 2004 00:22:32


If (on a polyphonic synth) two overlapping note on's occur and a not off
arrives, how does the synth decide which one to turn off (they could have
different note on velocity...) ?
TK
 
 
 

MIDI Note On/Off

Post by Jeffery S. » Thu, 30 Sep 2004 02:01:44


Depends on how the synth is implementing it, but most likely, any
note off or zero velocity note on will end any notes playing on that
note number.

More likely, most poly synths implementation only allows one sound
at a time on a given note number, so the overlapping note on would
turn off the previous sounding note.
--
*-__Jeffery Jones__________| *Starfire* |____________________-*
** Muskego WI Access Channel 14/25 < http://www.yqcomputer.com/ ~jeffsj/mach7/>
*Starfire Design Studio* < http://www.yqcomputer.com/ ;
 
 
 

MIDI Note On/Off

Post by Guenter Na » Thu, 30 Sep 2004 15:20:39


Note on A
Note on A
Note off A
Note off A

for notes with different note number or channel number it is clear, it
surely only turns off the one with identical number and channel.

for notes with same number and channel this is system dependent and not
defined in midi how it must behave.
In practice it will probably only turn off the sound of this number note
on this channel and not continue till next note on with these parameters.

In this case even the behavior of second note is system depending, it
might play the note twice or restart this note or ignore second note on.

MIDI file author should avoid this case. They could use aftertouch
instead to change velocity within playing note (what is usually sent by
synth when player changes pressure of a playing note).

Gter
http://www.yqcomputer.com/