import com.sun.image.codec.jpeg.*;

public void saveFrame(String filename) {
  BufferedImage img=new BufferedImage(width, height,
  BufferedImage.TYPE_INT_RGB);
  loadPixels();
  img.setRGB(0, 0, width, height, g.pixels, 0, width);

  String extn=filename.substring(filename.lastIndexOf('.')+1).toLowerCase();
  if (extn.equals("jpg")) {

    try{
      ByteArrayOutputStream out = new ByteArrayOutputStream();
      JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
      JPEGEncodeParam p = encoder.getDefaultJPEGEncodeParam(img);
      // set JPEG quality to 50% with baseline optimization
      p.setQuality(0.5,true);
      encoder.setJPEGEncodeParam(p);
      encoder.encode(img);

      File file = new File(savePath(filename));
      FileOutputStream fo = new FileOutputStream(file);
      out.writeTo(fo);
      println("saved "+filename);
    }
    catch(FileNotFoundException e){
      System.out.println(e);
    }
    catch(IOException ioe){
      System.out.println(ioe);
    }

  } else if (extn.equals("png")) { // add here as needed

    try {
      javax.imageio.ImageIO.write(img, extn, new File(savePath(filename)));
      println("saved "+filename);
    }
    catch(Exception e) {
      System.err.println("error while saving as "+extn);
      e.printStackTrace();
    }

  } else {
    super.saveFrame(filename);
  }
}