For loop adding notes to a midi file, toneJS

Question

I'm creating a midi file based on frequencies. I'm using ToneJS (in Node.js) to create the midi file with this code:

exports.createMidiFile = (req,res,next) => {
  // create a new midi file
var midi = new Midi()
// add a track
const track = midi.addTrack()
track.addNote({
  midi : Tone.Frequency(400).toMidi(),
  time : 0,
  duration: 10
})

// write the output
fs.writeFileSync("output.mid", new Buffer(midi.toArray()))
}

What im trying to do is a for loop to add notes to the same track. I tried:

for (var i = 0; i < length; i++){
track.addNote({
  midi : Tone.Frequency(i).toMidi(),
  time : 0,
  duration: 10
})
}

But when i try to open the file it says the file is damaged..

Thanks in advance friends.

What library are you using ? As far as I know, `new Midi()` is not native JavaScript — Mouradif, Jul 21 '20 at 14:18
I see in the documentation that the calls to `addNode()` ar chained. Try with `track = track.addNote()` — Mouradif, Jul 21 '20 at 15:07
i want to chain addNote() , so beside writing ```track.addNote().addNote().addNote()``` i want to have for loop to do it without adding it manualy — Elna Haim, Jul 21 '20 at 15:16

score 0 · Answer 1 · answered Jul 21 '20 at 16:13

0

Try writing your loop like this :

for (var i = 0; i < length; i++){
  track = track.addNote({
    midi : Tone.Frequency(i).toMidi(),
    time : 0,
    duration: 10
  })
}

Doing this makes it equivalent to chaining the calls to addNote()

answered Jul 21 '20 at 16:13

Mouradif

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ok i will give it a try and i will check if its working, thank you for answering. – Elna Haim Jul 21 '20 at 16:35
its not working :/ . i need to chain the addNote somehow... – Elna Haim Jul 21 '20 at 17:08

For loop adding notes to a midi file, toneJS

1 Answers1