midi-writer-js/runkit.js

A library providing an API for generating MIDI files.

const rkmidi = require('runkit-midi');
const MidiWriter = require('midi-writer-js');
const track = new MidiWriter.Track();
track.addEvent([
  new MidiWriter.NoteEvent({pitch: ['E4','D4'], duration: '4'}),
  new MidiWriter.NoteEvent({pitch: ['C4'], duration: '2'}),
  new MidiWriter.NoteEvent({pitch: ['E4','D4'], duration: '4'}),
  new MidiWriter.NoteEvent({pitch: ['C4'], duration: '2'}),
  new MidiWriter.NoteEvent({pitch: ['C4', 'C4', 'C4', 'C4', 'D4', 'D4', 'D4', 'D4'], duration: '8'}),
  new MidiWriter.NoteEvent({pitch: ['E4','D4'], duration: '4'}),
  new MidiWriter.NoteEvent({pitch: ['C4'], duration: '2'})
], function(event, index) {
    return {sequential: true};
  }
);

const write = new MidiWriter.Writer(track);
rkmidi(write.buildFile());