/*
 * LibCV example: analyzing difference frames
 *
 * Here we compute an avarage change factor using the autogenerated difference frames
 * the window will flash red if there's at least 5% change between 2 consecutive frames
 *
 * Make sure you edit the CAPTURE_DEVICE string and frame sizes to match your camera/input
 * LibCV currently requires the Sun Java Media Framework installed
 *
 * If your device description is correct but you're receiving an error message, please
 * re-run the JMFRegistry application and choose "Detect Capture devices" to revalidate
 *
 * If you're unsure where to get the device descriptor from, uncomment the line containing
 * listDevices() in the setup() method to print out information about all currently
 * recognized capture devices. 
 *
 * Please consult the javadoc of this library for more information
 * http://toxi.co.uk/p5/libcv/
 *
 * @author: Karsten Schmidt < i n f o -[ a t ]- t o x i . c o . u k >
 */ 

import toxi.video.capture.*;

String CAPTURE_DEVICE = "vfw:Microsoft WDM Image Capture (Win32):1";
int CAPTURE_WIDTH = 160;
int CAPTURE_HEIGHT = 120;

SimpleCapture capture;
LibCV libcv;

float indicator;

void setup() {
  size(100,100);
  capture = new JMFSimpleCapture();
  //JMFSimpleCapture.listDevices(System.out,true);
  if (!capture
    .initVideo(CAPTURE_DEVICE, CAPTURE_WIDTH, CAPTURE_HEIGHT, 0)) {
    println(capture.getError());
    // you might have to (re-)run the JMFRegistry application
    // devices sometimes are unrecognized
    System.exit(0);
  }
  libcv = new LibCV(this, capture);
}

void draw() {
  try {
    libcv.processFrame(libcv.getFrame());
    PImage dbuf=libcv.getDeltaBuffer();
    // compute an average change factor of the current delta buffer
    float sum=0;
    for(int i=0; i<dbuf.pixels.length; i++) sum+=dbuf.pixels[i] & 0xff;
    // flash red, if there's more than 5% change
    if (sum/dbuf.pixels.length/256 > 0.05) {
      indicator=255;
    } 
    else {
      indicator*=0.995;
    }
    fill(indicator,0,0);
    rect(0,0,width,height);
  }
  catch (IncompatibleSizeException e) {
    e.printStackTrace();
  }
}


public void stop() {
  libcv.stop(); // automatically takes care of capture object too
  super.stop();
}