Audio2.java

package ie.dit;

import ddf.minim.AudioInput;
import ddf.minim.Minim;
import ddf.minim.analysis.FFT;
import processing.core.PApplet;

public class Audio2 extends PApplet
{
    public static int SAMPLE_RATE = 44100;
    public static int RESOLUTION = 16;
    public static int FRAME_SIZE = 1024;

    Minim minim;
    AudioInput ai;
    FFT fft;
    
    public void settings()
    {
        size(FRAME_SIZE, 800);
        minim = new Minim(this);
        ai = minim.getLineIn(Minim.MONO, FRAME_SIZE, SAMPLE_RATE, RESOLUTION);
        fft = new FFT(FRAME_SIZE, SAMPLE_RATE);
    }

    float lerpedAverage = 0;

    public void draw()
    {
        background(0);
        colorMode(HSB);
        float halfH = height / 2;
        float total = 0;
        for(int i = 0 ; i < ai.bufferSize() ; i ++)
        {
            stroke(map(i, 0, FRAME_SIZE, 0, 255), 255, 255);
            line(i, halfH, i, halfH + ai.left.get(i) * halfH);
            total += (float) Math.abs(ai.left.get(i));
        }
        float average = total / (float) FRAME_SIZE;
        // Move lerped average 10% closer to average every frame
        // Smooths out sudden changes
        lerpedAverage = lerp(lerpedAverage, average, 0.1f);
        noStroke();
        fill(map(lerpedAverage, 0, 1, 0, 255), 255, 255);
        ellipse(width / 2, 100, lerpedAverage * 400, lerpedAverage * 400);

        fft.forward(ai.left);
        
        int maxIndex = -1;
        float max = Float.MIN_VALUE;

        for(int i = 0 ; i < fft.specSize() ; i ++)
        {
            stroke(map(i, 0, fft.specSize(), 0, 255), 255, 255);
            line(i, 0, i, fft.getBand(i) * 50);
            if (fft.getBand(i) > max)
            {
                maxIndex = i;
                max = fft.getBand(i);
            }
        }
        float freq = fft.indexToFreq(maxIndex);
        text("Frequency: " + freq, 100, 50);
    }
}