Processing Sound experiment #1

sound_experiment_1.pde

  
import processing.sound.*;

FFT fft;
AudioIn in;
Amplitude amp;

int bands = 512;
float[] spectrum = new float[bands];

void stop() {
  in.stop();
  super.stop();
}

void setup() {
  size(512, 360);
  //fullScreen();
  background(255);
    
  // Create an Input stream which is routed into the Amplitude analyzer
  fft = new FFT(this, bands);
  in = new AudioIn(this, 0);
  
  // start the Audio Input
  in.start();
  
  // patch the AudioIn
  fft.input(in);
  
  strokeWeight(2);
}      

void draw() { 
  fft.analyze(spectrum);

  float max = 0;
  int max_idx = 0;
  
  int[] circles = new int[bands];

  for(int i = 0; i < bands; i++){
    if (spectrum[i] > 0.005) {
      circles[i] = Math.round(spectrum[i] * 1000);
    }
  }
  
  background(0);
  
  stroke(255 - max_idx/3);
  for(int i = 0; i < bands; i++){
    if (circles[i] > 0) {
      fill(circles[i] / 2, circles[i] / 3, i/2);
      ellipse(i, height/3, circles[i], circles[i] );
    }
  }
   
  for(int i = 0; i < bands; i++){
    // The result of the FFT is normalized
    // draw the line for frequency band i scaling it up by 5 to get more amplitude.
    
    line( i, (height/2) - (spectrum[i]*height*5)/2, i, (height/2) + (spectrum[i]*height*5)/2 );
  } 
}