How can I code a server/client video and audio streaming application?

Question

I have to create a client/server system to stream video and audio. It would be very simple. Like youtube style. The server should attend clients providing a list of medias first and waiting the choice of each client to start streaming the media. Until create a socket and showing a simple list I'm on it ;) But I don't know which class could I use to stream. The example is basically youtube style. How can I start streaming, How can client pause reproduction, how can? I know how to stream text but what about video? Do you know any tutorial page? It's very different from this simple server client example?

import java.io.*; 
import java.io.*;
import java.net.*;

public class ThreadedEchoServer {

   public static void main(String[] args) {
      try {
         int i = 1;
         ServerSocket s = new ServerSocket(8189);

         while(true) {
            Runnable r = new ThreadedEchoHandler(incoming, i);
            Thread t = new Thread(r);
            t.start();
            i++;
         }
      } catch (IOException e) {
         e.printStackTrace();
      }
   }
}

class ThreadedEchoHandler implements Runnable {
   private Socket incoming;
   private int counter;

   public ThreadedEchoHandler(Socket i, int c) {
      incoming = i;
      counter = c;
   }

   public void run() {
      try {
         try {
            InputStream inStream = incoming.getInputStream();
            OutputStream outStream = incoming.getOutputStream();

            Scanner in = new Scanner(inStream);
            PrintWriter out = new PrintWriter(outStream);

            out.println("BYE to exit");
            boolean done = false;

            while (!done && in.hasNextLine()) {

               String line = in.nextLine()) {
               out.println("Echo: " + line);

               if (line.trim().equals("BYE"))
                  done = true;
               out.println("BYE to exit");
            }
         } finally {
            incoming.close();
         }
      } catch (IOException e) {
         e.printStackTrace();
      }
}

Hope you could clarify my ideas. Kind regards.

Answer 1

For streaming and talking to your clients, you need to define a protocol: Search the web for RTP and RTSP. It should give you a pretty good idea of what you need to implement these protocols or even create your own one.

As for implementing, take a look at the red5 project: http://red5.org/

Take a look at Xuggler as well: http://www.xuggle.com/xuggler/ This project will help you saving lots of lines of code. Note that its development has gone stale.

Cheers.

Answer 2

Check out the Java Media Framework (it has tutorials): http://java.sun.com/javase/technologies/desktop/media/jmf/

Does this even work?

     while(true) {
        Runnable r = new ThreadedEchoHandler(incoming, i);
        Thread t = new Thread(r);
        t.start();
        i++;
     }

I think your code would produce a bunch of threads with incoming socket connections... what you probably want to do is this:

     while(true) {
        Runnable r = new ThreadedEchoHandler(incoming.accept(), i);
        Thread t = new Thread(r);
        t.start();
        i++;
     }

The ThreadedEchoHandler should take a Socket instead of a ServerSocket. Accept blocks until a client connects, otherwise you'll be spawning an infinite number of threads without a connection... I don't think you have anything that will stop you from doing that at the moment.