Processing onSet detection with Minim

import ddf.minim.*;
import ddf.minim.analysis.BeatDetect;

Minim minim;
AudioInput in;

BeatDetect bd;

void setup() {
  size(512, 200, P3D);

  minim = new Minim(this);

  in = minim.getLineIn();

  // Read the docs at
  // http://code.compartmental.net/minim/javadoc/index.html?ddf/minim/analysis/BeatDetect.html
  bd = new BeatDetect();
  //bd.setSensitivity(20);
}

void draw() {
  background(0);
  stroke(255);

  for (int i = 0; i < in.bufferSize () - 1; i++) {
    line( i, 50 + in.left.get(i)*50, i+1, 50 + in.left.get(i+1)*50 );
    line( i, 150 + in.right.get(i)*50, i+1, 150 + in.right.get(i+1)*50 );
  }

  bd.detect(in.left);

  if(bd.isOnset()) {
    background(255);
  }
}