Pitch detection in audio from file

pitch.js

var audioContext = new (window.AudioContext || window.webkitAudioContext)();
function splitAudioArrayBuffer(buffer, segmentLength) {
  // Calculate the number of segments.
  const numberOfSegments = Math.ceil(buffer.length / segmentLength);

  // Create an array to store the segments.
  const segments = [];

  // Loop over the segments and create a new ArrayBuffer for each one.
  for (let i = 0; i < numberOfSegments; i++) {
    const start = i * segmentLength;
    const end = (i + 1) * segmentLength;
    const segment = buffer.slice(start, end);
    segments.push(segment);
  }

  // Return the array of segments.
  return segments;
}
document.getElementById('audio-form').addEventListener('submit', function(e) {
e.preventDefault();
const input = document.querySelector('id_content');
const reader = new FileReader();

reader.onload = function() {
 const arrayBuffer = reader.result;

 // Do something with the arrayBuffer here

// Create an AudioBuffer from the ArrayBuffer.
const audioBuffer = audioContext.decodeAudioData(arrayBuffer);
segments = splitAudioArrayBuffer(audioBuffer, parseInt(audioBuffer.duration * {{ pitches_per_second }}));
var upitches = [];
	var  uvolumes = [];
	var  unotes = [];
for(segment of segments) {
analyser = audioContext.createAnalyser();
	analyser.minDecibels = -100;
	analyser.maxDecibels = -10;
	analyser.smoothingTimeConstant = 0.85;
var source = audioContext.createBufferSource(segment);
	source.connect(analyser);
var bufferLength = analyser.fftSize;
	var buffer = new Float32Array(bufferLength);
	analyser.getFloatTimeDomainData(buffer);
	var autoCorrelateValue = autoCorrelate(buffer, buffer.sampleRate)
	var pitch = autoCorrelateValue;	
	bufferLength = analyser.frequencyBinCount;
	const dataArray = new Uint8Array(bufferLength);
	analyser.getByteFrequencyData(dataArray);
  	let sum = 0;
	for (const amplitude of dataArray) {
		sum += amplitude * amplitude
	}
	const volume = Math.sqrt(sum / dataArray.length)
	note = noteStrings[pitchToNote(pitch) % 12] + Math.floor(pitchToNote(pitch)/12 - 1);
	upitches.push(pitch.toFixed(2));
	unotes.push(note);
	uvolumes.push(volume);
}

// Ajax submit
  var form = document.getElementById("audio-form");
          let blob = new Blob(chunks, {"type": "audio/webm; codecs=opus" });
	  var formData = new FormData(form);
          formData.set("confirmation_id", String(Math.floor(Math.random() * 100000000)));
          formData.set("session", sessionBegan);
          var p = "";
          var v = "";
          var n = "";
	  for(pitch of upitches) {
		p = p + String(pitch) + ",";
	  }
	  for(volume of uvolumes) {
		v = v + String(volume) + ",";
	  }
	  for(note of unotes) {
		n = n + String(note) + ",";
	  }	  
	  formData.set("pitches", p.slice(0, -1));
          formData.set("volumes", v.slice(0, -1));
          formData.set("pitch_notes", n.slice(0, -1));
	  pitches = [];
	  volumes = [];
	  notes = [];
	  var id = formData.get("confirmation_id");
          $.ajax({
	    type: "POST",
	    url: window.location.href,
	    data: formData,
	    processData: false,
	    contentType: false,
	    timeout: 1000 * 60 * 10,
            tryCount: 0,
            retryLimit: 5,
            error: (xhr, textStatus, errorThrown) => {
			$(posted).addClass("fade-hidden");
			setTimeout(function() {
				$(posted).addClass("hide");
			}, 2000);
                    this.tryCount++;
                    if(this.tryCount >= this.retryLimit) return;
                    $.ajax(this);
            },
	    success: function(data) {
		$(posted).toggleClass("hide");
		setTimeout(function() {
                        $(posted).toggleClass("fade-hidden");
                        setTimeout(function() {
                                $(posted).toggleClass("hide");
                                $(posted).toggleClass("fade-hidden");
                        }, 2000);
                }, 2000);
                $.ajax({
                        url: "/audio/confirm/" + id + "/",
                        type: "POST",
                        success: function(data) {
                                if(data != "y") {
                                        $.ajax(this);
                                }
                        },
                });
	     },
	  });
};

reader.readAsArrayBuffer(input.files[0]);

}