Edge detection in Processing

edge_detect.java

import java.awt.image.BufferedImage;
import java.awt.image.WritableRaster;

PImage input, output;

void setup() {
  int width=400;
  int height=300;
  size(width,height);
  output = createImage(width,height,RGB);
  input = loadImage("car.jpg");
  loadPixels();

  // extract the BufferedImage
  BufferedImage bimage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
  bimage.getGraphics().drawImage(input.getImage(), 0, 0, null);

  // run edge detection
  CannyEdgeDetector detector = new CannyEdgeDetector();
  detector.setLowThreshold(0.5f);
  detector.setHighThreshold(6f);
  detector.setSourceImage(bimage);
  detector.process();
  BufferedImage edges = detector.getEdgesImage();

  // build the PImage from edges
  WritableRaster raster = edges.getRaster();
  raster.getDataElements(0, 0, width, height, output.pixels);

  output.save("/tmp/edges.png");
  noLoop();  // Makes draw() only run once
}

void draw() {
  image(output, 0, 0); 
}