/******************************************************************
 * The following code will save all the frames.                   *
 * Make sure you stop looping after a certain number of           *
 * frames so as not to run out of your hard drive storage.        *
 * To make a movie, go to Tools -> Movie Maker.                   *
 ******************************************************************/
int c = 255;
void setup() {
  size(400, 400);
  background(0);
  frameRate(2);
  noStroke();
}
void draw() {
  fill(c, random(100));
  float sz = random(30,200);
  ellipse(random(width), random(height), sz, sz);
  if(frameCount % 20 == 0) {
    c = 255 - c; // 255 0 255 0 255 0 ..
  }
  saveFrame("frames/####.png");
  if(frameCount > 120) { 
    // 60 seconds * 2 fps = 120
    noLoop();
  }
}