ArtNetClient.pde

import java.net.SocketException;
import java.util.List;
import java.net.InetAddress;

import artnet4j.ArtNet;
import artnet4j.ArtNetException;
import artnet4j.ArtNetNode;
import artnet4j.events.ArtNetDiscoveryListener;
import artnet4j.packets.ArtDmxPacket;

public class ArtNetClient {
  private int sequenceId;
  private ArtNet artnet;
  private ArtNetNode receiver;

  public ArtNetClient()
  {
    artnet = new ArtNet();
  }

  public void open()
  {
    open(null, null);
  }

  public void open(InetAddress in, String address)
  {
    try
    {
      // sender
      artnet.start(in);
      setReceiver(address);
    } 
    catch (SocketException e) {
      e.printStackTrace();
    } 
    catch (ArtNetException e) {
      e.printStackTrace();
    }
  }

  public void setReceiver(String address)
  {
    if (null == address)
      receiver = null;

    try
    {
      receiver = new ArtNetNode();
      receiver.setIPAddress(InetAddress.getByName(address));
    }
    catch (Exception e) {
      e.printStackTrace();
    }
  }

  public void close()
  {
    artnet.stop();
  }

  public void send(int universe, byte[] data)
  {
    send(receiver, universe, data);
  }

  public void send(ArtNetNode node, int universe, byte[] data)
  {
    ArtDmxPacket dmx = new ArtDmxPacket();

    dmx.setUniverse(0, universe);
    dmx.setSequenceID(sequenceId % 256);
    dmx.setDMX(data, data.length);

    if (receiver != null) {
      artnet.unicastPacket(dmx, node);
    } else {
      artnet.broadcastPacket(dmx);
    }
    
    sequenceId++;
  }
}

ArtNetTest.pde

import ddf.minim.*;
import ddf.minim.analysis.*;
import ddf.minim.effects.*;
import ddf.minim.signals.*;
import ddf.minim.spi.*;
import ddf.minim.ugens.*;

import java.net.InetAddress;
import java.util.Enumeration;

ArtNetClient artnet;

Minim minim;
AudioInput lineIn;
FFT         fft;

int i = 0;

byte[] buffer = new byte[512];

void setup()
{
  frameRate(120);
  size(500, 500);  
  
  minim = new Minim(this);
  lineIn = minim.getLineIn(Minim.STEREO, 4096, 44100, 8);
  fft = new FFT(lineIn.bufferSize(), lineIn.sampleRate());

  try
  {
    artnet = new ArtNetClient();
    byte[] ipAddr = new byte[]{10, 20, (byte)255, (byte)255};

    InetAddress address = InetAddress.getByAddress(ipAddr);

    artnet.open(null, "10.20.255.255");
  } 
  catch (Exception e) {
    e.printStackTrace();
  }
}

void draw()
{
  fft.forward( lineIn.mix );
  float c = map(fft.calcAvg(50, 500), 0, 9, 0, 1);
  float d = map((fft.calcAvg(500, 3000)), 0, 1, 0, 1);
  float e = map((fft.calcAvg(500, 1000)), 0, 1, 0, 1);
  
  for(i=0; i<12; i++) {
    int[] rgb = Wheel(((i * 256 / 12) + (frameCount % 256)) & 255);
 
    buffer[i*5] = (byte)(rgb[0]); //r
    buffer[(i*5)+1] = (byte)(rgb[1]); //g
    buffer[(i*5)+2] = (byte)(rgb[2]); //b
    //buffer[(i*5)+3] = (byte)0; //ww
    //buffer[(i*5)+4] = (byte)0;//kw

  }

  artnet.send(3, buffer);

  //i = (i + 1) % 256;
}

void stop()
{
  artnet.close();
}

int[] Wheel(int pos) {
  pos = 255 - pos;
  if(pos < 85) {
    return new int[]{255 - pos * 3, 0, pos * 3};
  }
  if(pos < 170) {
    pos -= 85;
    return new int[]{0, pos * 3, 255 - pos * 3};
  }
  pos -= 170;
  return new int[]{pos * 3, 255 - pos * 3, 0};
}