I know you can humanize notes within Reaper's MIDI editor, but where I can, I prefer to use Schwa's JSFX. Using the JSFX in lieu of the built in editor has a couple of features that I like:
1. I can leave my MIDI data pretty rigid in the editor (which makes it easier to read, filter, etc.) and still get a humanized effect.
2. I can automate the controls to create more variety in playback throughout the project.
3. I like the idea that my playback will never quite be the same (though some folks probably dislike that notion).
The problem I experienced with the native Reaper JSFX is that repeated notes would sometimes cut off earlier. The cause is that the randomized start times of notes would overlap the end times of previously played notes. The effect is that the note-off message for the first note might accidentally cutoff the second note if they were the same pitch.
You can see the impact of this in the rendered MIDI track below:
To demonstrate, I created a whole bunch of repeated 16th notes and quarter notes at C4 and A3 respectively. You can see in the arrange view that the repeating notes frequently get cutoff soon after they sound even though they look more or less fine in the MIDI editor.
My solution was to:
1: Include logic that sent a note-off message if a note of the same pitch was sent before the end of the prior pitch.
2: Sort the MIDI messages after they were randomized to ensure the process order matched the playback order.
You can see the result below:
You can still see some shifted start and end times due to humanize effect, but there is no overlap of notes of the same pitch. Thus, the MIDI in the arrange view looks very similar to the original (that is, no notes with abrupt note-off).
You can download my revision here:
https://stash.reaper.fm/29365/midi_humanizer_pcartwright
Feel free to leave comments or questions.
Revised MIDI Velocity and Timing Humanizer (repeat note fix)
Linear Mode
