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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <div class="js-message message"></div>
<div class="recorder">
  <div class="waveform">
    <canvas class="js-canvas waveform__canvas"></canvas>
              $blue-light: #49F1D5;
$blue: #2E748F;
$blue-dark: #153A49;

$white: #ffffff;
$black: #000000;

$red: #ED6A5F;

html {
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, $blue, $blue-dark); 
  font-size: 10px;

.waveform {
  position: relative;
  padding: 4rem 0;
  &__canvas {
    width: 100%;
    height: 40rem;

.message {
  transtion: opacity .4s ease-in-out;
  padding: 1rem 2rem;
  background: $red;
  opacity: 0;
  font-size: 1.6rem;
  font-family: Helvetica, Arial, sans-serif;
  color: $white;
  line-height: 1.5;
  &--visible {
    opacity: 1;
              // We'll store the value of te bars we want to draw in here
const bars = []

// An instance of AudioContext
const audioContext = new AudioContext();

// This will become our input MediaStreamSourceNode
let input = null;

// This will become our AnalyserNode
let analyser = null;

// This will become our ScriptProcessorNode
let scriptProcessor = null;

// Canvas related variables
const barWidth = 2;
const barGutter = 2;
const barColor = "#49F1D5";

let canvas = null;
let canvasContext = null;
let width = 0;
let height = 0;
let halfHeight = 0;
let drawing = false;

 * Process the input of the ScriptProcessorNode.
 * @param {audioProcessingEvent}
const processInput = audioProcessingEvent => {  
    // Create a new Uint8Array to store the analyser's frequencyBinCount 
    const tempArray = new Uint8Array(analyser.frequencyBinCount);

    // Get the byte frequency data from our array
    // Calculate the average volume and store that value in our bars Array

    // Render the bars

 * Calculate the average value from the supplied array.
 * @param {Array<Int>}
const getAverageVolume = array => {    
    const length = array.length;
    let values = 0;
    let i = 0;

    // Loop over the values of the array, and count them
    for (; i < length; i++) {
        values += array[i];

    // Return the avarag
    return values / length;

 * Render the bars.
const renderBars = () => {  
    if (!drawing) {
        drawing = true;

        window.requestAnimationFrame(() => {
            canvasContext.clearRect(0, 0, width, height);

            bars.forEach((bar, index) => {
                canvasContext.fillStyle = barColor;
                // Top part of the bar
                canvasContext.fillRect((index * (barWidth + barGutter)), (halfHeight - (halfHeight * (bar / 100))), barWidth, (halfHeight * (bar / 100)));

                // Bottom part of the bars
                canvasContext.fillRect((index * (barWidth + barGutter)), halfHeight, barWidth, (halfHeight * (bar / 100)));

            drawing = false;

// Wait untill the page has loaded
(function() {
    // Get the canvas element and context
    canvas = document.querySelector('canvas');
    canvasContext = canvas.getContext('2d');

    // Set the dimensions
    width = canvas.offsetWidth;
    height = canvas.offsetHeight;
    halfHeight = height / 2;

    // Set the size of the canvas context to the size of the canvas element
    canvasContext.canvas.width = width;
    canvasContext.canvas.height = height;

    // Get the users microphone audio.
        audio: true
    }).then(stream => {
        // Create the audio nodes
        input = audioContext.createMediaStreamSource(stream);
        analyser = audioContext.createAnalyser();
        scriptProcessor = audioContext.createScriptProcessor();

        analyser.smoothingTimeConstant = 0.3;
        analyser.fftSize = 1024;

        // Connect the audio nodes

        // Add an event handler
        scriptProcessor.onaudioprocess = processInput;
    }, error => {
        // Something went wrong, or the browser does not support getUserMedia
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