analyze_sound.java

/**
  * This sketch demonstrates how to use an FFT to analyze
  * the audio being generated by an AudioPlayer.
  * <p>
  * FFT stands for Fast Fourier Transform, which is a 
  * method of analyzing audio that allows you to visualize 
  * the frequency content of a signal. You've seen 
  * visualizations like this before in music players 
  * and car stereos.
  * <p>
  * For more information about Minim and additional features, 
  * visit http://code.compartmental.net/minim/
  */

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

Minim       minim;
AudioPlayer jingle;
FFT         fft;

void setup()
{
  size(512, 200, P3D);
  
  minim = new Minim(this);
  
  // specify that we want the audio buffers of the AudioPlayer
  // to be 1024 samples long because our FFT needs to have 
  // a power-of-two buffer size and this is a good size.
  jingle = minim.loadFile("jingle.mp3", 1024);
  
  // loop the file indefinitely
  jingle.loop();
  
  // create an FFT object that has a time-domain buffer 
  // the same size as jingle's sample buffer
  // note that this needs to be a power of two 
  // and that it means the size of the spectrum will be half as large.
  fft = new FFT( jingle.bufferSize(), jingle.sampleRate() );
  
}

void draw()
{
  background(0);
  stroke(255);
  
  // perform a forward FFT on the samples in jingle's mix buffer,
  // which contains the mix of both the left and right channels of the file
  fft.forward( jingle.mix );
  
  for(int i = 0; i < fft.specSize(); i++)
  {
    // draw the line for frequency band i, scaling it up a bit so we can see it
    line( i, height, i, height - fft.getBand(i)*8 );
  }
}

core.clj

(ns squid.core
  (:use [quil.core])
  (:import [ddf.minim Minim]
           [ddf.minim.analysis.*]
           [ddf.minim.*])
  (:require [squid.dynamic :as dynamic]))

(defsketch example
  :title "Sample sketch"
  :setup dynamic/setup
  :draw dynamic/draw
  :size [600 600]
  )

dynamic.clj

(ns squid.dynamic
  (:import [ddf.minim Minim])
  (:require [quil.core :refer :all]))

(def max-diam 50)

(defn number-circles-across []
  (/ (width) (* 2 max-diam)))

(defn draw-circle [index diam]
  (let [x (* (+ 1 index) max-diam)
        y (/ (height) 2)]

    (ellipse x y diam diam)))

(defn setup []
  (smooth)
  (random-seed 1)
  (frame-rate 2)
  (background 140)
  (fill 250 200 0)
  (dotimes [n 25] (draw-circle n 5)))

(defn draw []
  (background 140)
  (dotimes [n 25] (draw-circle n (random 10 (- max-diam 5))))
)