Display current frame in applet.

Question

I am writing a Java applet that creates a media player. It plays a movie and I want to get the current frame. I have the code for this:
FramePositioningControl fpc = ( FramePositioningControl)  player.getControl("javax.media.control.FramePositioningControl");
int currentFrame = fpc.mapTimeToFrame(player.getMediaTime());I have created a text field and this is displayed on one of the panels of media player.
My problem is that I can only get the frame number for the first frame to appear in the text field and it doesn't change for each frame.
I have my code in the public synchronized void controllerUpdate(ControllerEvent evt) method as follows:
tf3.setText(""+currentFrame);Any ideas as to how I can get each frame number to appear?
I hope I have made myself clear enough.
Thanks in advance,
Wallace

Answer 1

I have my code in the public synchronized void
controllerUpdate(ControllerEvent evt) method as
follows:controllerUpdate() is not called every time a new frame is encountered. It is called, for example, when the Processor or Player becomes "Realized", or is started or stopped.
From your Processor or Player, you need to obtain the TrackControl that is an instance of VideoFormat.
(note p is a Processor created and in the "Configured" state at this point in the code)
          TrackControl tc[] = null;
          // Obtain the track controls.
          tc = p.getTrackControls();
          // Search for the track control for the video track.
          TrackControl videoTrack = null;
          for( int i = 0; i < tc.length; i++ )
               if( tc[ i ].getFormat() instanceof VideoFormat )
                    videoTrack = tc[ i ];
                    break;
          }You then need to create a custom Codec (or chain of Codecs) which you will insert into the data flow using p.setCodecChain( Codec[] codecs ) Override the process() method in your custom Codec to update your counter, as it will be called once for each frame.
For example:
public class PreAccessCodec implements Codec
     public final int process( Buffer in, Buffer out )
//UPDATE YOUR COUNTER HERE!
         // Swap the data between the input & output.
         Object data = in.getData();
         in.setData(out.getData());
         out.setData(data);
         // Copy the input attributes to the output
         out.setFormat(in.getFormat());
         out.setLength(in.getLength());
         out.setOffset(in.getOffset());
         return BUFFER_PROCESSED_OK;
}You will have to do a little searching through java.sun.com to find out about implementing a custom Codec, but I guarantee this will help you out... it is fundamental to the success of my application. I wish you luck!