Use a capture device twice at the same time?

Question

I have write a application using JMF. But I have a big question that how can I use a capture device several times at the same time????
For example:
I create a player to play video from my webcam on my PC ,and then I want to send the video stream from my webcam to another PC at the same time. But I failed--only one task can work.
For example:
1, I write a class Player and another class RTPTransmit. Then I send the same medialocator to two of them. Then there will be a exception said that capture device is in use. And only one task can work.
2, I write a class Player and another class RTPTransmit. Then I use :
dataSource1 = Manager.createDataSource( locator );
dataSource2 = Manager.createCloneableDataSource( dataSource1 );
then I send dataSource1 to Player object to play video on local PC and send dataSource2 to RTPTransmit to send video to another PC. But only one task will work too.
My question is that how can I use a capture device several times at the same time???
I have tried several ways and sill can not find a method. If anyone know how to do,could you tell me please? Thank you very much.

Answer 1

Yes ,I use Manager.createCloneableDataSource() method to create the clone of the datasource ,but it can not work too. The java doc illustration is :
Creates a cloneable DataSource. The returned DataSource implements the SourceCloneable interface and enables the creation of clones by the createClone method.
If the input DataSource implements SourceCloneable, it will be returned right away as the result. Otherwise, a "proxy" DataSource is created. It implements the SourceCloneable interface and can be used to generate other clones.
When createCloneableDataSource is called on a DataSource, the returned DataSource should be used in place of the original DataSource. Any attempt to use the original DataSource may generate unpredictable results.
It means that if I clone a datasoure from original datasource, then the createCloneableDataSource() method will return a datasuouce implements interface SourceCloneable, right ? I see that the intereface SourceCloneable has a abstract method createClone() , but when I use createCloneableDataSource() to get a source clone, I find that I can not use method createClone(), why??? For example: data1 is the
orginal datasource. Then:
DataSource data1 = Manager.createDateSource( locator );
DataSource data2 = Manager.createCloneableDataSource( data1 );
now data2 is the "proxy" datasource which implemnets the interface, right? But I can not use data2.cloneClone() ,why? Then I write the fllowing code:
DataSource data3 = Mangaer.createCloneableDataSource( data2 );
DataSource data4 = Manager.createCloneableDataSource( data2 );
playOnLocalPc = new PlayOnLocalPc( data3 );
playOnLocalPc.start();
rtpTransmit = new RTPTransmit( data4 );
rtpTransmit.start();
PlayOnLocalPc and RTPTransmit is my own class to play or transmit video stream. But they can not work at the same time. If I play video from webcam on local PC and then start to transmit stream to other PC , the play window will become black. Why?????It is too strange. Dose anyone know the reason ,please tell me, thank you very much. Giving some example code will be better:) Thank you again!