流桌面的VLCJ

Question

我试图写一个Java程序，它允许一个用户充当服务器和流自己的桌面（视频&音频），然后其他用户作为客户和观看他们的桌面的实时数据流（类似于Twitch，Webex，Skype屏幕共享等）。我正在使用VLCJ，尽管我没有使用它的承诺，所以如果有更好的解决方案，我全是耳朵。这是从我提供的链接复制的代码：

package test.java; 

import uk.co.caprica.vlcj.discovery.NativeDiscovery; 
import uk.co.caprica.vlcj.player.MediaPlayerFactory; 
import uk.co.caprica.vlcj.player.headless.HeadlessMediaPlayer; 
import test.java.VlcjTest; 

/** 
* An example of how to stream a media file over HTTP. 
* <p> 
* The client specifies an MRL of <code>http://127.0.0.1:5555</code> 
*/ 
public class StreamHttp extends VlcjTest { 

    //when running this it requires an MRL (Media Resource Locator) 
    //fancy term for saying the file you want to stream. This could be a url to another 
    //location that streams media or a filepath to a media file you want to stream 
    //on the system you are running this code on. 
    public static void main(String[] args) throws Exception { 
     new NativeDiscovery().discover(); 
     if(args.length != 1) { 
      System.out.println("Specify a single MRL to stream"); 
      System.exit(1); 
     } 

     //the media you are wanting to stream 
     String media = args[0]; 
     //this is the IP address and port you are wanting to stream at 
     //this means clients will connect to http://127.0.0.1:5555 
     //to watch the stream 
     String options = formatHttpStream("127.0.0.1", 5555); 

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

     //this creates a the actual media player that will make calls into the native 
     //vlc libraries to actually play the media you supplied. It does it in 
     //a headless fashion, as you are going to stream it over http to be watched 
     //instead of playing it locally to be watched.  
     MediaPlayerFactory mediaPlayerFactory = new MediaPlayerFactory(args); 
     HeadlessMediaPlayer mediaPlayer = mediaPlayerFactory.newHeadlessMediaPlayer(); 

     //this simply starts the player playing the media you gave it 
     mediaPlayer.playMedia(media, options); 

     // Don't exit 
     //basically you don't want the thread to end and kill the player, 
     //so it just hangs around and waits for it to end. 
     Thread.currentThread().join(); 
    } 

    private static String formatHttpStream(String serverAddress, int serverPort) { 
     StringBuilder sb = new StringBuilder(60); 
     sb.append(":sout=#duplicate{dst=std{access=http,mux=ts,"); 
     sb.append("dst="); 
     sb.append(serverAddress); 
     sb.append(':'); 
     sb.append(serverPort); 
     sb.append("}}"); 
     return sb.toString(); 
    } 
} 

我将“screen：//”作为参数传递给此程序。当我运行的代码，我得到这个错误信息：

[000000000038b250] access_output_http access out: Consider passing --http-host=IP on the command line instead. 
[000000001ccaa220] core mux error: cannot add this stream 
[000000001cc72100] core decoder error: cannot create packetizer output (RV32) 

我试图寻找一个解决方案，但所有我能找到的是这样的： Video Streaming in vlcj 虽然这个用户有同样的错误，我解决不了我的问题从这个链接，虽然我确实使用StreamHttp代码示例。我是一个相对缺乏经验的程序员，所以如果我错过了一个明显的解决方案，那么我很抱歉。我正在使用Java 1.8，Windows 7 64位。

Answer 1

你需要的东西是这样的：

String media = "screen://"; 
String[] options = { 
    ":sout=#transcode{vcodec=FLV1,vb=4096,scale=0.500000}:http{mux=ffmpeg{mux=flv},dst=:5000/" 
}; 

这里显示的关键的东西是一个“SOUT”字符串（通过http在这种情况下），以视频转码，然后又追加“SOUT”字符串流。

在这个例子中的字符串，HTTP流仅端口（5000，任意选择的）被指定。没有指定主机，所以它表示本地主机。你可以有像“dst = 127.0.0.1：8080 /”或任何你需要的东西。

你将不得不选择/实验所需的特定转码/流媒体选项。这些选项没有一个适合所有人的尺寸。

足注：

您实际上可以使用VLC本身产生此字符串为您服务。

开始VLC，然后选择要播放的媒体。

，而不用按“播放”的，使用小窗口以选择“流”来代替。这将打开Streaming向导，您可以在其中选择所有选项。

在向导的最后，你开始玩之前，它会显示你需要的字符串。