URGENT---Error regarding Cannot connect to Capture Device

Question

Hello Everyone, I am new to JMF and I am trying to build a project using JMF. In the project I need to capture images from webcam and display it on a window.
I have written the following class for this:
import java.awt.*;
import java.awt.image.*;
import javax.media.*;
import javax.media.control.*;
import javax.media.format.*;
import javax.media.protocol.*;
import javax.media.util.*;
public class CameraController
     private Player player;
     * Initialises the video capture device.
     * @param name the name of the device (e.g. <code>vfw:Microsoft WDM Image Capture (Win32):0</code>).
     * @param locator the location of the device (e.g. <code>vfw://0</code>).
     * @param size
     * @throws Exception if there was a problem accessing the camera.
     public CameraController(String name, String locator, Dimension size) throws Exception
          // Create capture device
          System.out.println("Initialising video capture device: "+name);
          try
               CaptureDeviceInfo captureDeviceInfo = CaptureDeviceManager.getDevice(name);
               VideoFormat videoFormat = null;
               Format[] formats = captureDeviceInfo.getFormats();
               for (int i=0; i<formats.length; i++)
                    if (((VideoFormat)formats).getSize().equals(size))
                         videoFormat = (VideoFormat)formats[i];
                         break;
               DataSource dataSource = Manager.createDataSource(new MediaLocator(locator));*
               FormatControl[] formatControls = ((CaptureDevice)dataSource).getFormatControls();
               for (int i=0; i<formatControls.length; i++)
                    if (formatControls[i]!=null)
                         Format supportedFormats[] = formatControls[i].getSupportedFormats();
                         if (supportedFormats!=null)     
                              for (int j=0; j<supportedFormats.length; j++)
                                   if (supportedFormats[j].matches(videoFormat))
                                        formatControls[i].setFormat(videoFormat);                              
               CaptureDeviceInfo deviceInfo = ((CaptureDevice)dataSource).getCaptureDeviceInfo();
               ((CaptureDevice)dataSource).disconnect();
               player = Manager.createRealizedPlayer(deviceInfo.getLocator());
               player.start();
               try { Thread.sleep(3000); }
               catch (InterruptedException e) {}
          catch (Exception e)
               System.out.println("Error Initialising video capture device!");
               throw e;
     public void shutdown()
          player.close();
          player.deallocate();
     public BufferedImage getFrame()
          FrameGrabbingControl frameGrabber = (FrameGrabbingControl)player.getControl("javax.media.control.FrameGrabbingControl");
          Buffer buf = frameGrabber.grabFrame();
          Image img = (new BufferToImage((VideoFormat)buf.getFormat()).createImage(buf));
          if (img==null)
               System.out.println("Error: Capture device doesnt appear to be initialised yet.");
               return null;          // happens if video device isn't properly initialised yet
          BufferedImage buffImg = new BufferedImage(img.getWidth(null), img.getHeight(null), BufferedImage.TYPE_INT_RGB);
          Graphics2D g = buffImg.createGraphics();          
          g.drawImage(img, null, null);
          return buffImg;
     public Component getVisualComponent()
          return player.getVisualComponent();
There is another class GUI which calls the shutdown() function on occurrence of WindowClosing event.
When I try to run this, It does run for the first time but after that, the following exception occurs:
java.io.IOException: Could not connect to capture device
javax.media.NoDataSourceException: Error instantiating class: com.sun.media.protocol.vfw.Datasource: java.io.IOException: Could noy connect to capture device
at javax.media.Manager.createDataSource(Manager.java.1012)
at CamerController.<init>(CameraController.java:57) ------ line where datasource is declared
It doesn't run until I restart my laptop and then again after restart it runs only for the first time..
I don't understand where is the problem. I am using Windows7, JMF 2.1.1, NetBeans 6.7.
Kindly help me to find out the problem in this. Its extremely URGENT..!!!!

Answer 1

Anjani_Bansal wrote:
2. I am not shouting at anyone.Actually, I think even 12-year old girls on MySpace understand that TYPING IN ALL CAPS IS TAKEN TO BE SHOUTING on the internetz... so when you say its URGENT, everyone who understands the internet is going to read that as you SHOUTING the word URGENT.
Which is simply impolite.
3. I didn't ask YOU to answer my query. I asked only those people who are there to help and who understand my situation.Actually, you said everyone. Andrew is a person. Therefore, you did ask him to answer your question...and further, you simply asked "Kindly help me to find out the problem in this". Apparently Andrew took "this" to mean forum etiquette, which he was quite kind to help you with.
For others[ Not You] :-
Sorry every one if you think I am shouting. I am kindly requesting you for help.
Thanks for understanding..Telling people on a forum that you need help URGENTLY isn't particularly asking kindly. Ignoring the whole rudeness of typing in all-caps, there's also the whole urgent thing. Do you think that people are going to read your post and then go "Eh, this kid doesn't sound like he's in a hurry. I think I'll come back and answer his question in a few days, let him sweat it out".
Seriously, people add urgent to their posts like somehow it's the emergency flag on a help desk.
This isn't a helpdesk, and telling us how urgently you need help isn't going to positively affect the speed at which you get help... in fact, it's far more likely to get you completely ignored by the people with the answer than it is to get you help any faster...
Speaking of being ignored, I'm pretty sure I "kindly" suggested something for you to try above, and you never reported back the results of my suggestion. Am I to take from the fact you decided to spend your time sparing with Andrew that (1) you don't really care about fixing your problem (2) you're not really paying attention to the people who're trying to help you (3) your problem isn't really all that URGENT to begin with? (4) you somehow think your time is more important than mine and I should ignore your thread entirely? [I'd seriously advise looking through a few threads on this forum to see where the help comes from before you think about answering this one... there are 2 people that regularly help people in here, and you've already pissed one of them off...]