Problem with JMF to capture video from webcam

I have been trying to capture a video from my webcam for about 2 months now and i found that JMF could that and i got many codes but nothing works.The JMF studio and JMF Registry are working correctly and i can know the devices and the formats .The code below gives a null pointer exception in returning the video and audio devices although the devices are detected by the jmf registry.Could anyone please help me about that? I`d really appreciate it.Thanks in advance.

    package JMF;import java.awt.*;import java.awt.event.*;import java.util.Vector;import javax.media.*;import javax.media.format.*;import javax.media.protocol.DataSource;
    public class CaptureDeviceDialog extends Dialog implements ActionListener, ItemListener {
      boolean configurationChanged = false;Vector devices;Vector audioDevices;VectorvideoDevices;Vector audioFormats;Vector videoFormats;Choice audioDeviceCombo;Choice videoDeviceCombo;Choice audioFormatCombo;Choice videoFormatCombo;
      public CaptureDeviceDialog(Frame parent, String title, boolean mode) {
        super(parent, title, mode);
        init();
      }

      private void init() {
        setSize(450, 180);
        Panel p = new Panel();
        p.setLayout(null);

    Label l1 = new Label("Audio Device(s)");
    Label l2 = new Label("Video Device(s)");
    Label l3 = new Label("Audio Format(s)");
    Label l4 = new Label("Video Format(s)");
    audioDeviceCombo = new Choice();
    videoDeviceCombo = new Choice();
    audioFormatCombo = new Choice();
    videoFormatCombo = new Choice();

    Button OKbutton = new Button("OK");
    Button cancelButton = new Button("Cancel");


    p.add(l1);
    l1.setBounds(5, 5, 100, 20);
    p.add(audioDeviceCombo);
    audioDeviceCombo.setBounds(115, 5, 300, 20);
    p.add(l3);
    l3.setBounds(5, 30, 100,20);
    p.add(audioFormatCombo);
    audioFormatCombo.setBounds(115, 30, 300,20);
    p.add(l2);
    l2.setBounds(5, 55, 100, 20);
    p.add(videoDeviceCombo);
    videoDeviceCombo.setBounds(1开发者_如何学C15, 55, 300, 20);
    p.add(l4);
    l4.setBounds(5, 80, 100, 20);
    p.add(videoFormatCombo);
    videoFormatCombo.setBounds(115, 80, 300, 20);
    p.add(OKbutton);
    OKbutton.setBounds(280, 115, 60, 25);
    p.add(cancelButton);
    cancelButton.setBounds(355, 115, 60, 25);

    add(p, "Center");
    audioDeviceCombo.addItemListener(this);
    videoDeviceCombo.addItemListener(this);
    OKbutton.addActionListener(this);
    cancelButton.addActionListener(this);

    //get all the capture devices
    devices = CaptureDeviceManager.getDeviceList ( null );
    CaptureDeviceInfo cdi;
    if (devices!=null && devices.size()>0) {
      int deviceCount = devices.size();
      audioDevices = new Vector();
      videoDevices = new Vector();

      Format[] formats;
      for ( int i = 0;  i < deviceCount;  i++ ) {
        cdi = (CaptureDeviceInfo) devices.elementAt ( i );
        formats = cdi.getFormats();
        for ( int j=0;  j<formats.length; j++ ) {
          if ( formats[j] instanceof AudioFormat ) {
            audioDevices.addElement(cdi);
            break;
          }
          else if (formats[j] instanceof VideoFormat ) {
            videoDevices.addElement(cdi);
            break;
          }
        }
      }

      //populate the choices for audio
      for (int i=0; i<audioDevices.size(); i++) {
        cdi  = (CaptureDeviceInfo) audioDevices.elementAt(i);
        audioDeviceCombo.addItem(cdi.getName());
      }

      //populate the choices for video
      for (int i=0; i<videoDevices.size(); i++) {
        cdi  = (CaptureDeviceInfo) videoDevices.elementAt(i);
        videoDeviceCombo.addItem(cdi.getName());
      }

      displayAudioFormats();
      displayVideoFormats();

    } // end if devices!=null && devices.size>0
    else {
      //no devices found or something bad happened.
    }
  }

  void displayAudioFormats() {
    //get audio formats of the selected audio device and repopulate the audio format combo
    CaptureDeviceInfo cdi;
    audioFormatCombo.removeAll();

    int i = audioDeviceCombo.getSelectedIndex();
    //i = -1 --> no selected index

    if (i!=-1) {
      cdi = (CaptureDeviceInfo) audioDevices.elementAt(i);
      if (cdi!=null) {
        Format[] formats = cdi.getFormats();
        audioFormats = new Vector();
        for (int j=0; j<formats.length; j++) {
          audioFormatCombo.add(formats[j].toString());
          audioFormats.addElement(formats[j]);
        }
      }
    }
  }

  void displayVideoFormats() {
    //get audio formats of the selected audio device and repopulate the audio format combo
    CaptureDeviceInfo cdi;
    videoFormatCombo.removeAll();

    int i = videoDeviceCombo.getSelectedIndex();
    //i = -1 --> no selected index

    if (i!=-1) {
      cdi = (CaptureDeviceInfo) videoDevices.elementAt(i);
      if (cdi!=null) {
        Format[] formats = cdi.getFormats();
        videoFormats = new Vector();
        for (int j=0; j<formats.length; j++) {
          videoFormatCombo.add(formats[j].toString());
          videoFormats.addElement(formats[j]);
        }
      }
    }
  }


  public CaptureDeviceInfo getVideoDevice() {
    CaptureDeviceInfo cdi = null;
    if (videoDeviceCombo!=null) {
      int i = videoDeviceCombo.getSelectedIndex();
      cdi = (CaptureDeviceInfo) videoDevices.elementAt(i);
      System.out.println("videoDeviceCombo!=null");
      if(videoDevices.elementAt(i)!=null)
        System.out.println("element at videoDeviceCombo!=null");
    }
    return cdi;
  }

  public CaptureDeviceInfo getAudioDevice() {
    CaptureDeviceInfo cdi = null;
    //System.out.println("audioDeviceCombo!=null");
    if (audioDeviceCombo!=null) {
      int i = audioDeviceCombo.getSelectedIndex();
      cdi = (CaptureDeviceInfo) audioDevices.elementAt(i);
    if(audioDevices.elementAt(i)!=null)
      System.out.println("eleme");

    }
    return cdi;
  }


  public Format getAudioFormat() {
    Format format = null;
    if (audioFormatCombo!=null) {
      int i = audioFormatCombo.getSelectedIndex();
      format = (Format) audioFormats.elementAt(i);
    }
    return format;
  }

  public Format getVideoFormat() {
    Format format = null;
    if (videoFormatCombo!=null) {
      int i = videoFormatCombo.getSelectedIndex();
      format = (Format) videoFormats.elementAt(i);
    }
    return format;
  }

  public boolean hasConfigurationChanged() {
    return configurationChanged;
  }

  public void actionPerformed(ActionEvent ae) {
    String command = ae.getActionCommand().toString();
    if (command.equals("OK")) {
      configurationChanged = true;
    }
    dispose();
  }public void itemStateChanged(ItemEvent ie) {
    System.out.println(ie.getSource().toString());
    if (ie.getSource().equals(audioDeviceCombo))
      displayAudioFormats();
    else
      displayVideoFormats();

  }
}

`

package JMF;

import java.awt.*;
import java.awt.event.*;
import java.io.*;

import javax.media.*;
import javax.media.format.*;
import javax.media.protocol.*;

import java.awt.*;
import java.awt.event.*;
import java.util.Vector;
import javax.media.*;
import javax.media.format.*;
import javax.media.protocol.DataSource;


public class JMF extends Frame implements ActionListener, ItemListener, WindowListener,
  ControllerListener {

  CaptureDeviceInfo audioCDI = null;
  CaptureDeviceInfo videoCDI = null;
  String audioDeviceName = null;
  String videoDeviceName = null;
  Player videoPlayer;
  Player audioPlayer;
  Format videoFormat;
  Format audioFormat;
  Player dualPlayer;  //for merging audio and video data sources

  DataSource dataSource; //of the capture devices

  public JMF(String title) {
    super(title);
    addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent we) {
        dispose();
      }
    });
    MenuBar mb = new MenuBar();
    setMenuBar(mb);
    Menu menuConfigure = new Menu("Configure");
    mb.add(menuConfigure);

    Menu menuAction = new Menu("Action");
    mb.add(menuAction);

    /* menu items for Configure */
    MenuItem menuItemSetting = new MenuItem("Capture Device");
    menuItemSetting.addActionListener(this);
    menuConfigure.add(menuItemSetting);

    /* menu items for Action */

    MenuItem a1 = new MenuItem("Capture");
    a1.addActionListener(this);
    menuAction.add(a1);
    MenuItem a2 = new MenuItem("Play");
    a2.addActionListener(this);
    menuAction.add(a2);
    MenuItem a3 = new MenuItem("Stop");
    a3.addActionListener(this);
    menuAction.add(a3);

  }

  public void actionPerformed(ActionEvent ae) {
    String command = ae.getActionCommand().toString();
    if (command.equals("Capture Device")) {
      registerDevices();
    }
    else if (command.equals("Play")) {
      play();
    }
    else if (command.equals("Capture")) {
      capture();
    }
    else if (command.equals("Stop")) {
      stop();
    }
  }

  void registerDevices() {
    CaptureDeviceDialog cdDialog = new 
      CaptureDeviceDialog(this, "Capture Device", true);
    cdDialog.show();
    if (!cdDialog.hasConfigurationChanged())
      return;

    //configuration has changed, update variables.
    audioCDI = cdDialog.getAudioDevice();
    if (audioCDI!=null) {
      audioDeviceName = audioCDI.getName();
      System.out.println("Audio Device Name: " + audioDeviceName);
    }

    videoCDI = cdDialog.getVideoDevice();
    if (videoCDI!=null) {
      videoDeviceName = videoCDI.getName();
      System.out.println("Video Device Name: " + videoDeviceName);
    }

    //Get formats selected, to be used for creating DataSource
    videoFormat = cdDialog.getVideoFormat();
    audioFormat = cdDialog.getAudioFormat();
  }

  void capture() {
    if (audioCDI==null && videoCDI==null)
      registerDevices();

    try {
      if (!(audioCDI==null && videoCDI==null)) {

     /* This works, but now we end up having 2 players

        videoPlayer = Manager.createPlayer(videoCDI.getLocator());
        audioPlayer = Manager.createPlayer(audioCDI.getLocator());
        videoPlayer.addControllerListener(this);
        videoPlayer.start();
        audioPlayer.start();
     */
        DataSource[] dataSources = new DataSource[2];
        System.out.println("Creating data sources.");

        dataSources[0] = Manager.createDataSource(new MediaLocator("dsound://"));
        dataSources[1] = Manager.createDataSource(new MediaLocator("vfw://0"));
        DataSource ds = Manager.createMergingDataSource(dataSources);
        dualPlayer = Manager.createPlayer(ds);
        dualPlayer.addControllerListener(this);
        dualPlayer.start();
      }
      else
        System.out.println("CDI not found.");
    }
    catch (Exception e) {
      System.out.println(e.toString());
    }
  }

  void play() {
    try {
      FileDialog fd = new FileDialog(this, "Select File", FileDialog.LOAD);
      fd.show();
      String filename = fd.getDirectory() + fd.getFile();
      dualPlayer = Manager.createPlayer(new MediaLocator("file:///" + filename));

      System.out.println("Adding controller listener");
      dualPlayer.addControllerListener(this);

      System.out.println("Starting player ...");
      dualPlayer.start();
    }
    catch (Exception e) {
      System.out.println(e.toString());
    }
  }

  void stop() {
    if (dualPlayer!=null) {
      dualPlayer.stop();
      dualPlayer.deallocate();
    }
  }

public synchronized void controllerUpdate(ControllerEvent event) {
    System.out.println(event.toString());

    if (event instanceof RealizeCompleteEvent) {
      Component comp;

      System.out.println("Adding visual component");
      if ((comp = dualPlayer.getVisualComponent()) != null)
        add ("Center", comp);
      System.out.println("Adding control panel");
      if ((comp = dualPlayer.getControlPanelComponent()) != null)
        add("South", comp);
      validate();
    }
  }

  public void itemStateChanged(ItemEvent ie) {}
  public void windowActivated(WindowEvent we) {}
  public void windowClosed(WindowEvent we) {}
  public void windowClosing(WindowEvent we) {}
  public void windowDeactivated(WindowEvent we) {}
  public void windowDeiconified(WindowEvent we) {}
  public void windowIconified(WindowEvent we) {}
  public void windowOpened(WindowEvent we) {}



  public static void main(String[] args) {
    JMF myFrame = new JMF("Java Media Framework Project");
    myFrame.show();
    myFrame.setSize(300, 300);
  }

}

This is because your code is not detecting the webcam

you must copy the jmf.properties file to the same directory as your executable jar

you will find the jmf.properties file int the lib folder of your jmf installation.

For me it was C:\Program Files\JMF2.1.1e\lib\jmf.properties

I think I had a similar problem. JMStudio was finding my webcam but my java code was not. The issue for me was with device format. the CaptureDeviceManager.getDeviceList( VideoFormat ) requires a VideoFormat as a parameter. the two I know of are rgb and yuv.

Try calling one of:

• CaptureDeviceManager.getDeviceList(new VideoFormat("rgb"))
• CaptureDeviceManager.getDeviceList(new VideoFormat("yuv")).

Your webcam should show up in one list or the other.

If you are using a 64 bit processor, uninstall the jmf. Reinstall the jmf but this time to the drive C: and not to program files: eg. C:/jmf 2.1.1e.

If you have a problem with the video format, I think you should give the format like this:

CaptureDeviceManager.getDeviceList(new YUVFormat());

It's working for me.