MIDI Compressor, anybody?

Can you "print" it to an Audio file? Then you can compress it as you usually would.

I've done MIDI compression using a combination of velocity scale and offset.
Your  compression ratio is simply the scaling.  For 2:1, just scale by 50%.  Then make-up gain is the velocity Gain you add back in. 
 
You'll find the Scale Velocity command in the Process menu.  Here I have it set for a 2:1

 
It will likely be too soft after that so dial in the Gain knob on the MIDI or Instrument track to taste (if using the inspector) or the Gain slider in the track strip.
 
For example if your input range was velocities 20 - 80 and you'd like to bring up the values that are too soft, a 50% scale gives you 10 - 40, so add 40 back in on gain to get 50 - 80.
 
If on the other hand your louds are too hot, like 60 - 127 and you want to keep the lows where they are, then 60 - 127 will scale to 30 - 63, so add 30 gain to get you to 60 - 93.
 
But you don't really have to worry about the numbers too much, just adjust the gain to taste.
 
<Update>  Just saw your 2nd post where you want a dynamic adjustment based on distance from a threshold.  For that you'd likely need an MFX.  Or I suppose a cal script could be modified to accomplish something interesting.
 
Keith
 
 

I do what Jimbo does too. Works for most stuff. 
Is this a piano part? I discovered it by accident one day while editing a snare drum that was part of a multi drum track. I noticed if I highlighted the snare only the snare velocity bars were highlighted. cool. 
 
Basically with midi velocity if a track has either some notes way to loud or way to low it's pretty easy to use velocity scaling to squish it into a smaller range. but once you discover the piano roll trick you'll never use that. 
 
What your asking for is not really a compression. 

Ultimate MIDI dynamic range manipulator:
http://www.azslow.com/index.php/topic,275.0.html
 
The curve for "MIDI Compressor" should look like the curve for audio compressors: https://en.wikipedia.org/wiki/Dynamic_range_compression
so:
* when the line is 45 degree from 0 to 127, there is no changes (1:1)
* other angle after some point means that point is "the threshold" and the ration depends from the angle
* the whole curve shifter up means then "gain" by that shift amount.
But in practice you can just draw what you want to make it sound "right" for you
 
 
MIDI has 127 possible values only, so that is not a big deal to draw exact required curve even pixel by pixel.
I can make a preset for my another (universal) MFX plug-in with threshold, ration and gain, but Velocity MFX is more intuitive and precise for the purpose (till you need multi-band MIDI compression...).
 
Do not forget to keep 0 (the very first point) as 0 to avoid side effects !

Sonar has one built in, under midi fx called Cakewalk FX Midi Event Filter. I used it a lot when one of my keyboard keys was stuck on 127 full velocity. It's very useful and full of control


Actually im sorry... I used velocity plugin and it worked very well

^^^ this this.. (lol)
 
volume is not equal to velocity.. compression is for volume