Using LibVLC compiled for android to display DVB subtitles from an MPEG2 stream

Question

Using the following code I was able to play back a udp stream (mpeg2 ts) which has 3 tracks (video, audio and dvb subtitles), but I am trying to retrieve the subtitle track and display it, i couldn't find any clear documentation on how to do it.

   // Create LibVLC
ArrayList<String> options = new ArrayList<String>();
        options.add("-vvv"); // verbosity
        options.add("--autoscale");

libvlc = new LibVLC(this, options);
        holder.setKeepScreenOn(true);

// Creating media player
mMediaPlayer = new MediaPlayer(libvlc);
        mMediaPlayer.setAspectRatio("16:9");
        mMediaPlayer.setEventListener(mPlayerListener);


// Seting up video output
final IVLCVout vout = mMediaPlayer.getVLCVout();
        vout.setVideoView(mSurface);

        if (mSubtitlesSurface != null)
        vout.setSubtitlesView(mSubtitlesSurface);
        vout.setWindowSize(1920,1080);
        vout.addCallback(this);
        vout.attachViews();
    Media m = new Media(libvlc, Uri.parse(media));
    mMediaPlayer.setMedia(m);
    mMediaPlayer.play();

I am trying to use mMediaPlayer.getMedia().getTrackCount() and mMediaPlayer.getSpuTracksCount() which are returning zero in all cases; even the basic audio and video tracks are not counted.

Any help on this?

Note: I compiled LibVLC from [https://wiki.videolan.org/AndroidCompile/] and got the .aar archive to my project.

Answer 1

An argument added to options will help show the subtitles:

// Create LibVLC
    ArrayList<String> options = new ArrayList<String>();
    options.add("-vvv"); // verbosity
    options.add("--autoscale");
    args.add("--sub-track=0");//this option is used to show the first subtitle track
    libvlc = new LibVLC(this, options);
    holder.setKeepScreenOn(true);

    // Creating media player
    mMediaPlayer = new MediaPlayer(libvlc);
    mMediaPlayer.setAspectRatio("16:9");
    mMediaPlayer.setEventListener(mPlayerListener);


    // Seting up video output
    final IVLCVout vout = mMediaPlayer.getVLCVout();
    vout.setVideoView(mSurface);

    if (mSubtitlesSurface != null)
        vout.setSubtitlesView(mSubtitlesSurface);
    vout.setWindowSize(1920,1080);
    vout.addCallback(this);
    vout.attachViews();
    Media m = new Media(libvlc, Uri.parse(media));
    mMediaPlayer.setMedia(m);
    mMediaPlayer.play();