Piano Heatmap Analysis (Part 1)

Published September 10, 2015 on Chandler Swift's Blog Source

I have always been curious about what the most-used key on my piano is. Songs like Billy Joel’s “Prelude” (C4) or Beethoven’s “Für Elise” (A2) must throw off averages significantly, especially when practiced repeatedly, right? Also, I thought it would be cool to figure out how many keys total have been played: they should add up quickly! There do exist programs that do this for computer keyboards (and here are my stats, if somewhat out of date), but as far as I could tell there wasn’t a good option for a piano keyboard.

This should, in theory, be relatively simple. Nearly all electronic pianos (and such things) have a MIDI output connection, which means all that has to be done is to plug this into a computer and record the keystrokes as they roll in. So how hard can it be? I figured I’d try making on my own.

To start, I based it off a wonderful piece of freeware called MIDI-OX. So far, I haven’t come up with anything MIDI-related that it can’t do. Well, it can’t produce a heatmap, but still, it’s pretty great! What it can do is save a log of all the MIDI keystrokes as they come in, which can be analyzed later to compare numbers of keystrokes. It’s pretty simple:

  • Plug in your MIDI device.
  • Start MIDI-OX.
  • If you press a key on your keyboard, you should see entries on the screen.
  • Go to File > Log, and check “Enable Logging”.
  • Check “Append to Log” if you want old entries saved rather than overwritten to give a cumulative log.

That will give you your output log. If you’re feeling particularly Regex-y, you can search the file yourself, otherwise experiments.chandlerswift.com/piano-heatmap/ has my (strongly beta) tester; just upload the log file and see your results, pretty graph coming soon! As a general rule, about 6000 keys per MB of log file is not unreasonable, depending on how extensively you use the pedal.

And for anyone who’s wondering, my first few days’ worth of logged keys in semi-readable form are available here, with D4 my most played key.

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