使用套接字 fd 在手机之间传输实时视频

我是android编程的新手，发现自己陷入了困境。我一直在研究各种从手机到手机流式传输实时视频的方法，似乎它大部分功能都可用，当然除了最重要的部分：播放流。它似乎是从一部手机发送流，但第二部手机无法播放流。

这是游戏方的代码

public class VideoPlayback extends Activity implements Callback {
MediaPlayer mp;
private SurfaceView mPreview;
private SurfaceHolder holder;
private TextView mTextview;
public static final int SERVERPORT = 6775;
public static String SERVERIP="192.168.1.126";
Socket clientSocket;
private Handler handler = new Handler();
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    mPreview = (SurfaceView) findViewById(R.id.surfaceView1);
    mTextview = (TextView) findViewById(R.id.textView1);
    holder = mPreview.getHolder();
    holder.addCallback(this);
    holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    mTextview.setText("Attempting to connect");
    mp = new MediaPlayer();
    Thread t = new Thread(){
        public void run(){
            try {
                    clientSocket = new Socket(SERVERIP,SERVERPORT);
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        mTextview.setText("Connected to server");
                    }
                });
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        try {
                            ParcelFileDescriptor pfd = ParcelFileDescriptor.fromSocket(clientSocket);
                            pfd.getFileDescriptor().sync();
                            mp.setDataSource(pfd.getFileDescriptor());
                            pfd.close();
                            mp.setDisplay(holder);
                            mp.prepareAsync();
                            mp.start();
                        } catch (IOException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }

                    }
                });

            } catch (UnknownHostException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    };
    t.start();
}

这是流媒体端的代码

public class VideoStreaming extends Activity{
// User Interface Elements
VideoView mView;
TextView connectionStatus;
SurfaceHolder mHolder;
// Video variable
MediaRecorder recorder; 
// Networking variables
public static String SERVERIP="";
public static final int SERVERPORT = 6775;
private Handler handler = new Handler();
private ServerSocket serverSocket;  
/** Called when the activity is first created. */
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    // Define UI elements
    mView = (VideoView) findViewById(R.id.video_preview);
    connectionStatus = (TextView) findViewById(R.id.connection_status_textview);
    mHolder = mView.getHolder();
    mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    SERVERIP = "192.168.1.126";
    // Run new thread to handle socket communications
    Thread sendVideo = new Thread(new SendVideoThread());
    sendVideo.start();
}
 public class SendVideoThread implements Runnable{
    public void run(){
        // From Server.java
        try {
            if(SERVERIP!=null){
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        connectionStatus.setText("Listening on IP: " + SERVERIP);
                    }
                });
                serverSocket = new ServerSocket(SERVERPORT);
                while(true) {
                    //listen for incoming clients
                    Socket client = serverSocket.accept();
                    handler.post(new Runnable(){
                        @Override
                        public void run(){
                            connectionStatus.setText("Connected.");
                        }
                    });
                    try{
                            // Begin video communication
                            final ParcelFileDescriptor pfd = ParcelFileDescriptor.fromSocket(client);
                            handler.post(new Runnable(){
                                @Override
                                public void run(){
                                    recorder = new MediaRecorder();
                                    recorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
                                    recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);                 
                                    recorder.setOutputFile(pfd.getFileDescriptor());
                                    recorder.setVideoFrameRate(20);
                                    recorder.setVideoSize(176,144);
                                    recorder.setVideoEncoder(MediaRecorder.VideoEncoder.H263);
                                    recorder.setPreviewDisplay(mHolder.getSurface());
                                    try {
                                        recorder.prepare();
                                    } catch (IllegalStateException e) {
                                        // TODO Auto-generated catch block
                                        e.printStackTrace();
                                    } catch (IOException e) {
                                        // TODO Auto-generated catch block
                                        e.printStackTrace();
                                    }
                                    recorder.start();
                                }
                            });
                    } catch (Exception e) {
                        handler.post(new Runnable(){
                            @Override
                            public void run(){
                                connectionStatus.setText("Oops.Connection interrupted. Please reconnect your phones.");
                            }
                        });
                        e.printStackTrace();
                    }
                }
            } else {
                handler.post(new Runnable() {
                    @Override
                    public void run(){
                        connectionStatus.setText("Couldn't detect internet connection.");
                    }
                });
            }
        } catch (Exception e){
            handler.post(new Runnable() {
                @Override
                public void run() {
                    connectionStatus.setText("Error");
                }
            });
            e.printStackTrace();
        }
        // End from server.java
    }
}

尝试创建 MediaPLayer 时收到以下错误

05-24 16:25:39.360: ERROR/MediaPlayerService(88): offset error
05-24 16:25:39.360: ERROR/MediaPlayer(11895): Unable to to create media player
05-24 16:25:39.360: WARN/System.err(11895): java.io.IOException: setDataSourceFD failed.: status=0x80000000
05-24 16:25:39.360: WARN/System.err(11895):     at android.media.MediaPlayer.setDataSource(Native Method)
05-24 16:25:39.360: WARN/System.err(11895):     at android.media.MediaPlayer.setDataSource(MediaPlayer.java:811)
05-24 16:25:39.360: WARN/System.err(11895):     at com.conti.VideoPlayBack.VideoPlayback$1$2.run(VideoPlayback.java:63)
05-24 16:25:39.360: WARN/System.err(11895):     at android.os.Handler.handleCallback(Handler.java:587)
05-24 16:25:39.360: WARN/System.err(11895):     at android.os.Handler.dispatchMessage(Handler.java:92)
05-24 16:25:39.360: WARN/System.err(11895):     at android.os.Looper.loop(Looper.java:132)
05-24 16:25:39.360: WARN/System.err(11895):     at android.app.ActivityThread.main(ActivityThread.java:4025)
05-24 16:25:39.360: WARN/System.err(11895):     at java.lang.reflect.Method.invokeNative(Native Method)
05-24 16:25:39.360: WARN/System.err(11895):     at java.lang.reflect.Method.invoke(Method.java:491)
05-24 16:25:39.360: WARN/System.err(11895):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
05-24 16:25:39.360: WARN/System.err(11895):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
05-24 16:25:39.360: WARN/System.err(11895):     at dalvik.system.NativeStart.main(Native Method)

有人能解决这个问题吗？提前致谢！

我找到了一个开源项目来实现我正在尝试的事情。它通过 IP 摄像机处理带有元数据的视频。虽然它不直接将视频发送到手机，但它确实可以播放视频以供各种设备观看。源代码可以在以下项目页面找到http://code.google.com/p/ipcamera-for-android/ http://code.google.com/p/ipcamera-for-android/.

在 Android 4.4 中，还有另一种方式来播放实时 MJPEG 流。您正在播放的流应由其他设备通过 UDP 端口进行广播。假设我们有一个流在 192.168.0.101:8080 上广播。我们可以通过在布局中添加 WebView 来播放流。然后在我们的活动中我们执行以下操作：

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.mjpeg_activity);
    // Grab instance of WebView
    WebView webView = (WebView)findViewById(R.id.webViewStream);
    // Set page content for webview
    webView.loadData("<html><head><meta name='viewport' content='target-densitydpi=device-dpi,initial-scale=1,minimum-scale=1,user-scalable=yes'/></head><body><center><img src=\"http://192.168.0.101:8080/\" alt=\"Stream\" align=\"middle\"></center></body></html>", "text/html", null);
    webView.getSettings().setBuiltInZoomControls(true);
}

在内容中，我们告诉网页使用设备的 dpi。为了支持用户在网页上进行缩放，我添加了以下内容：initial-scale=1，minimum-scale=1，user-scalable=yes。最初图像是原始大小并且不能变小。用户现在可以缩放图像以放大或缩小到其原始大小。删除最小比例将使用户能够完全控制缩放，但可能会导致图像太小而无法找到它。