用ffmpeg将低延迟RTSP视频流到android

Question

我正试图用KitKat将Ubuntu12.04个人电脑上的摄像头实时视频传输到安卓设备上。到目前为止，我已经编写了ffserver配置文件来接收ffm提要并通过rtsp协议广播它。我可以在同一局域网中的另一台计算机上观看流的播放。

如何在android设备上观看流？下面的代码可以很好地工作时，当网络摄像头的图像是用vlc，但它没有与ffmpeg：

public class MainActivity extends Activity implements MediaPlayer.OnPreparedListener,
        SurfaceHolder.Callback {

    final static String RTSP_URL = "rtsp://192.168.1.54:4424/test.sdp";

    private MediaPlayer _mediaPlayer;
    private SurfaceHolder _surfaceHolder;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // Set up a full-screen black window.
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        Window window = getWindow();
        window.setFlags(
                WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        window.setBackgroundDrawableResource(android.R.color.black);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
        setContentView(R.layout.activity_main);

        // Configure the view that renders live video.
        SurfaceView videoView =
                (SurfaceView) findViewById(R.id.videoView); //where R.id.videoView is a simple SurfaceView element in the layout xml file
        _surfaceHolder = videoView.getHolder();
        _surfaceHolder.addCallback(this);
        _surfaceHolder.setFixedSize(320, 240);
    }
    @Override
    public void surfaceCreated(SurfaceHolder surfaceHolder) {
        _mediaPlayer = new MediaPlayer();
        _mediaPlayer.setDisplay(_surfaceHolder);
        Context context = getApplicationContext();
        Uri source = Uri.parse(RTSP_URL);
        try {
            // Specify the IP camera's URL and auth headers.
            _mediaPlayer.setDataSource(context, source);

            // Begin the process of setting up a video stream.
            _mediaPlayer.setOnPreparedListener(this);
            _mediaPlayer.prepareAsync();
        }
        catch (Exception e) {}
    }
    @Override
    public void onPrepared(MediaPlayer mediaPlayer) {
        _mediaPlayer.start();
    }
}

我的ffserver.config文件：

HTTPPort 8090
RTSPBindAddress 0.0.0.0
RTSPPort 4424
MaxBandwidth 10000
CustomLog -

<Feed feed1.ffm>
        File /tmp/feed1.ffm
        FileMaxSize 20M
        ACL allow 127.0.0.1
</Feed>
<Stream test1.sdp>
    Feed feed1.ffm
    Format rtp  
    VideoCodec libx264
    VideoSize 640x480
    AVOptionVideo flags +global_header
    AVOptionVideo me_range 16
    AVOptionVideo qdiff 4
    AVOptionVideo qmin 10
    AVOptionVideo qmax 51
    Noaudio
    ACL allow localhost
        ACL allow 192.168.0.0 192.168.255.255
</Stream>

我使用以下命令启动流：ffmpeg -f v4l2 -i /dev/video0 -c:v libx264 -b:v 600k http://localhost:8090/feed1.ffm

Answer 1

这一错误很可能是由VLC的不同编码参数引起的，而FFmpeg - VLC可以使用Android能够支持的编码参数，但是FFmpeg可以使用不支持的参数(很可能是AVC配置文件和级别)。尝试通过FFmpeg命令行选项和ffserver.config强制使用基线或主配置文件和YUV 4:2:0像素格式。