JMF驱动问题

  下面是一段捕获摄像头数据的程序(运行成功),我想捕获显示器的数据应该怎么办,str2是摄像头驱动的名字,那显示器驱动的名字是什么?
  各位大侠请指教,小弟先谢谢了
  import javax.media.*;
  import java.awt.event.*;
  import java.awt.*;
  public class SpJieKou {
  public static Player player;
  private CaptureDeviceInfo di;
  private MediaLocator ml;
  String str2 = "vfw:Microsoft WDM Image Capture (Win32):0";
  public SpJieKou(){
   try{
   di = CaptureDeviceManager.getDevice(str2);
   ml = di.getLocator();
   player = Manager.createRealizedPlayer(ml);
   player.start();
   }catch(Exception e){
   e.printStackTrace();
   }
  }//end
  
  void go(){
   HqFrame fr = new HqFrame();
   Component comp;
   if ((comp = player.getVisualComponent()) != null)
   {
   fr.add(comp, BorderLayout.CENTER);
   fr.setVisible(true);
   }
  }//end
  
  public static void main(String[] args) {
  
   SpJieKou sss = new SpJieKou();
   sss.go();
  }//end
  }
  //YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
  class HqFrame extends Frame {
  
   public HqFrame() {
   MenuBar menuBar = new MenuBar();
   Menu menuFile = new Menu();
   MenuItem menuFileExit = new MenuItem();
  
   menuFile.setLabel("File");
   menuFileExit.setLabel("Exit");
  
   menuFileExit.addActionListener
   (
   new ActionListener() {
   public void actionPerformed(ActionEvent e) {
   HqFrame.this.windowClosed();
   }
   }
   );
  
   menuFile.add(menuFileExit);
   menuBar.add(menuFile);
   setTitle("Hq");
   setMenuBar(menuBar);
   setSize(new Dimension(450, 400));
  
  
   this.addWindowListener
   (
   new WindowAdapter() {
   public void windowClosing(WindowEvent e) {
   HqFrame.this.windowClosed();
   }
   }
   );
   }
   protected void windowClosed() {
  
   System.exit(0);
   }
  }