var mic;

​

function setup() {

  createCanvas(500, 500);

​

  // Create an Audio input

  mic = new p5.AudioIn();

​

  // start the Audio Input.

  // By default, it does not .connect() (to the computer speakers)

  mic.start();

}

​

function draw() {

  background(200);

​

  // Get the overall volume (between 0 and 1.0)

  var vol = mic.getLevel();

  fill(255,0,255);

  stroke(0);

​

  // Draw an ellipse with height based on volume

  var h = map(vol, 0, 1, 0, height/2);

  ellipse(width/2,height/2, 25+h ,25 +h);

}

​