Video Capture Applet

Question

Hi all, I wanted to write a code that allows me to capture video from my webcam and show me in the applet window. But the I have seen the webcam being activated but I can't see anything on the screen when I terminate the applet the camera switches of (diactivated). Please tell me the problems with applets? Basically I used a processor to capture the video and used it to produce a data source. I then used a player to play the data source. I have used createrelizedplayer method. If you need the code I will post it.
Thank you.

Answer 1

Hi Talha thank you for your prompt response. BTW, I removed all calls to system.exit(0) method and the error code changed. Also I was using the file protocol (file: as FILE:) so after I change everything, the error chnaged. I will post it below. To answer your questions:
-- Which OS are you using? Vista? (then there are little chances that you would succeed) - XP (with SP3)
-- Have you tried running the applet in Applet Viewer? - I tried IE and Firefox (I will try Applet viewer)
-- Are you sure your program is foolproof, i.e. Is is working as Application? - I am sorry I don't get you.
-- You can post your effort at code ( enclose it in tags) - You mean I should post my code. If you mean that I will post it after the erro message.
Thank you again.
------- the error message ------
java.security.AccessControlException: access denied (java.io.FilePermission \foo.avi read)
     at java.security.AccessControlContext.checkPermission(Unknown Source)
     at java.security.AccessController.checkPermission(Unknown Source)
     at java.lang.SecurityManager.checkPermission(Unknown Source)
     at java.lang.SecurityManager.checkRead(Unknown Source)
     at java.io.File.exists(Unknown Source)
     at com.sun.media.datasink.file.Handler.open(Handler.java:263)
     at JMFAppletCapture5.init(JMFAppletCapture5.java:108)
     at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
     at java.lang.Thread.run(Unknown Source)
java.lang.NullPointerException
     at JMFAppletCapture5.start(JMFAppletCapture5.java:139)
     at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
     at java.lang.Thread.run(Unknown Source)
Exception: java.lang.NullPointerException
------ my code----- the following code in init() method:
     MediaLocator videoMediaLocator = new MediaLocator("vfw:Microsoft WDM Image Capture (Win32):0");
     try{
     processor = Manager.createProcessor(videoMediaLocator);
     }catch (Exception e) { Stdout.logAndAbortException(e);}
     processor.configure();
     try{
     Thread.sleep(4000);
     } catch( Exception e ) { System.out.println( "Error:" + e ); }
     processor.setContentDescriptor(new
                  FileTypeDescriptor(FileTypeDescriptor.MSVIDEO));
     processor.realize();
     try{
     Thread.sleep(4000);
     } catch( Exception e ) { System.out.println( "Error:" + e ); }
     MediaLocator dest = new MediaLocator("FILE://foo.avi");
      DataSink filewriter = null;
      try {
          filewriter = Manager.createDataSink(processor.getDataOutput(), dest);
          filewriter.open();
      } catch (NoDataSinkException e) {
          e.printStackTrace();
      } catch (IOException e) {
          e.printStackTrace();
      } catch (SecurityException e) {
          e.printStackTrace();
---- and the following in start() method-----
     try{
     processor.start();
     }      catch (Exception e) { Stdout.logAndAbortException(e);}
     try {
          filewriter.start();
      } catch (IOException e) {
          e.printStackTrace();
     try{
     Thread.sleep(10000);
     } catch( Exception e ) { System.out.println( "Error:" + e ); }
     processor.stop();
     processor.close();
     filewriter.close();
------- the exception  java.lang.NullPointerException   was raised  by      processor.start();  statement. I think I should start the processor after the datasink.
Edited by: Zelalem on Jan 24, 2009 8:17 AM