​

function setup() {

  createCanvas(400, 400);

  noStroke();

​

// microphone input

  mic = new p5.AudioIn();

  mic.start();

​

  // initializes amplitude analyzer

  amp = new p5.Amplitude();

  amp.setInput(mic);

}

​

function draw() {

  background(0);

​

  // gets amplitude level and increases sensitivity

  let vol = amp.getLevel() * 3; // increase sensitivity by multiplying

​

  // map the amplitude to control the radius of the gradient

  let radius = map(vol, 0, 0.3, 100, width);

​

  // radial gradient

  drawRadialGradient(width / 2, height / 2, radius);

}

​

function drawRadialGradient(x, y, radius) {

  let innerColor = color(0, 77, 102); // green

  let outerColor = color(0, 229, 80); // blue

  for (let r = radius; r > 0; r--) {

    let inter = map(r, 0, radius, 0, 1);

    let c = lerpColor(outerColor, innerColor, inter);

    fill(c);

    ellipse(x, y, r * 2, r * 2);

  }

}