The simplest way to record MIDI.

Also a nice simple live MIDI visualizer.

If you've got a MIDI keyboard, plug in and try it out.

Built with SimpleMidiInput.js and MidiFile.js

• Attempt to open MIDI port when device is connected but port is closed, so you don't need to refresh the page

• Fix track length (end time)

• Replace fork on github banner with a small link somewhere

• Improve layout on mobile / small viewport size

• Fade out overlay when playing (with a button to show info again)

• A way to clear/reset other than refreshing, with a confirmation prompt (unless you just saved?)

• Save progressively to local storage

  • This is the killer feature IMO, letting you record for long periods of time without fear of loss
  • Note: must handle multiple tabs without conflict
    • Could be separate recording slots per tab, but then there'd have to be a way to recover different sessions, vs having just one
    • Could use a scheme of saving chunks including notes since the last time of the last chunk (where the last write wins for a chunk) (and assume connected inputs are the same, which should be fine) - with potential complexity around trying not to duplicate or drop notes around chunk borders
    • Could use a scheme where one tab is somehow elected as the one to save MIDI to local storage, but this doesn't seem nice... it would probably have to be chunked anyways
  • Specifically stress test the length of recording
  • Make it clear it's continuing off a previous recording session / recording was recovered

• Show note velocity (already recorded)

• Record + show aftertouch pressure

• Record instrument changes, maybe show as horizontal line with text for instrument number/name

• Support Pitch Bend Range selection

• Record miscellaneous MIDI events, maybe even SysEx (optionally)?

• Maybe allow scrolling back (pausing automatically (not recording, just the view))

• Color notes by channel or instrument (doesn't matter much with a single keyboard)

• View options: horizontal mode, zooming, maybe themes

• Offline support with a service worker