Search code examples
javavlcmulticastlive-streamingvlcj

Best way to live stream video from java server to android client?

I've been searching the best way to live stream PC's screen from Java server to Android client since few days now but I can't find an other way to TCP socket. I want to stream from PC to Android client.

For now I just send images (frames) through TCP sockets. It works fine but here are the cons:

  • large bandwidth consumption (unicast through multiple clients)
  • serveral seconds shift between server and client
  • low frame rate

I tried with UDP socket but how to deal with maximum size packet of 64Ko ? The best solution will be UDP with multicast but I read some problems about it on Android, that is device dependent.

Thanks in advance for your answers !

Solution

  • I finally succeed to stream my PC's screen through RTP on Java server

    Code:

    public static void main(String[] args) throws Exception {
    boolean found = new NativeDiscovery().discover();
    System.out.println(found);
    System.out.println(LibVlc.INSTANCE.libvlc_get_version()); 

    String media = "screen://";
    String options = formatRtpStream("230.0.0.1", 5555);

    System.out.println("Streaming '" + media + "' to '" + options + "'");

    MediaPlayerFactory mediaPlayerFactory = new MediaPlayerFactory(args);
    EmbeddedMediaPlayer mediaPlayer = mediaPlayerFactory.newEmbeddedMediaPlayer();

    Canvas canvas = new Canvas();
    canvas.setBackground(Color.black);
    CanvasVideoSurface videoSurface = mediaPlayerFactory.newVideoSurface(canvas);
    mediaPlayer.setVideoSurface(videoSurface);

    // Creating a JFrame to display stream (duplicate)
    JFrame f = new JFrame("vlcj duplicate output test");
    f.add(canvas);
    f.setSize(800, 600);
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.setVisible(true);

    mediaPlayer.playMedia(media,
        options,
        ":no-sout-rtp-sap",
        ":no-sout-standard-sap",
        ":sout-all",
        ":sout-keep"
    );

    // Don't exit
    Thread.currentThread().join();
}

private static String formatRtpStream(String serverAddress, int serverPort) {
    StringBuilder sb = new StringBuilder(60);
    sb.append(":sout=");
    // Transcode with codec (mp4v here), 30 FPS, not resized (scale 1), audio disabled (only video).
    sb.append("#transcode{vcodec=mp4v,fps=30,scale=1,noaudio}");
    // Creating RTP address
    sb.append(":rtp{dst=");
    sb.append(serverAddress);
    sb.append(",port=");
    sb.append(serverPort);
    // Encapsulation method used for the resulting stream, this option has to be set.
    sb.append(",mux=ts}");
    return sb.toString();
}

    Display resulting stream in a window:

    You can replace this:

    sb.append(":rtp{dst=");
sb.append(",mux=ts}");

    By this:

    sb.append(":duplicate{dst=display,dst=rtp{dst=");
sb.append(",mux=ts}}");

    This way you will be able to see the resulting stream.

    Some interesting links: