Copy on right for blue channel mucking everything up.

copy_on_reference.pde

import gab.opencv.*;
import processing.video.*;
import java.awt.*;
 
Capture webcam_frame;
OpenCV opencv;

// Capture resolution of webcam.
int capture_x = 960;
int capture_y = 720;
 
void setup() {
  // Dump list of webcams capabilities.
  get_webcam_capabilities();

  // Make viewport size.
  size(capture_x * 2, capture_y);

  // Resolution + fps requested from webcam.
  webcam_frame = new Capture(this, capture_x, capture_y, 15);

  // Opencv wrapper.
  opencv = new OpenCV(this, capture_x, capture_y);
  opencv.useColor(HSB);

  // Send the request for webcam to start dumping frames.
  webcam_frame.start();

  // Disable looping in draw.
  noLoop();
}

// Dumps the webcam frames.
void draw() {
  // Get the next frame.
  webcam_frame.read();
  
  // Display the video image on the processing window.
  set(0, 0, webcam_frame);
  
  // Store the current frame.
  opencv.loadImage(webcam_frame);

  // Get only blue stuff;
  opencv.getB();
  
  // Save the b channel informaiton.
  PImage b_channel = opencv.getSnapshot();
  
  // Load that again but as input.
  opencv.loadImage(b_channel);
  // opencv.useGray();
  // opencv.threshold(80);
  
  
  // Do a diff between the old and new image frames.
  // opencv.diff(webcam_frame);
  image(b_channel, capture_x, 0);
}
 
// Dump list of webcams capabilities.
void get_webcam_capabilities(){
  // Read all camera params.
  String[] cameras = Capture.list();
  
  // Dump all params to terminal.
  println("Available cameras:");
  for (int i = 0; i < cameras.length; i++)
    println(cameras[i]);
}
 
// Called everytime a new camera frame is avalible.
void captureEvent(Capture webcam) {
  println("Capture event fired");
  
  // Redraw the GUI.
  redraw();
}

Line 52 being uncommented makes the value b_channel on line 58 gray, pah.