Qt AVPlayer

Free and open-source Qt Media Player library based on FFmpeg.

• Should be used to decode and fetch video/audio/subtitle frames.

• Could be used to synchronize frames based on pts or ignore any synchronization and decode frames as soon as possible.

• Supports FFmpeg Bitstream Filters and FFmpeg Filters including simplified filter_complex.

• Supports multiple parallel filters for one input, which generates multiple outputs.

• Based on Qt platform the video frames are sent in specific format:

  • VA-API for Linux: DRM with EGL or X11 with GLX.
  • VDPAU for Linux.
  • Video Toolbox for macOS and iOS.
  • D3D11 for Windows.
  • MediaCodec for Android.

  Note: Not all ffmpeg decoders or filters support HW acceleration. In this case software decoders are used.

• It is up to an application to decide how to process the frames.

  • But there is experimental support of converting video frames to QtMultimedia's QVideoFrame for copy-free rendering if possible. Note: Not all Qt's renders support copy-free rendering. Also QtMultimedia does not always provide public API to render the video frames. And, of course, for best performance both decoding and rendering should be accelerated.
  • Audio frames could be played by QAVAudioOutput which is a wrapper of QtMultimedia's QAudioSink

Features

1. QAVPlayer supports playing from an url or QIODevice or from avdevice:

   player.setSource("http://clips.vorwaerts-gmbh.de/big_buck_bunny.mp4");
   player.setSource("/home/lana/The Matrix Resurrections.mov");
   
   // Playing from qrc
   QFile file(QLatin1String(":/alarm.wav"));
   file.open(QIODevice::ReadOnly));
   player.setSource("alarm", &file);
   
   // Getting frames from the camera in Linux
   player.setSource("/dev/video0");
   // Or Windows
   player.setInputFormat("dshow");
   player.setSource("video=Integrated Camera");
   // Or MacOS
   player.setInputFormat("avfoundation");
   player.setSource("default");
   // Or Android
   player.setInputFormat("android_camera");
   player.setSource("0:0");
   
   player.setInputOptions({{"user_agent", "QAVPlayer"}});
   
   // Using various protocols
   player.setSource("subfile,,start,0,end,0,,:/root/Downloads/why-qtmm-must-die.mkv");
   

2. Easy getting video and audio frames:

   QObject::connect(&player, &QAVPlayer::videoFrame, [&](const QAVVideoFrame &frame) {
       // QAVVideoFrame is comppatible with QVideoFrame
       QVideoFrame videoFrame = frame;
       
       // QAVVideoFrame can be converted to various pixel formats
       auto convertedFrame = frame.convert(AV_PIX_FMT_YUV420P);
       
       // Easy getting data from video frame
       auto mapped = videoFrame.map(); // downloads data if it is in GPU
       qDebug() << mapped.format << mapped.size;
       
       // The frame might contain OpenGL or MTL textures, for copy-free rendering
       qDebug() << frame.handleType() << frame.handle();
   });
   
   // Audio frames could be played using QAVAudioOutput
   QAVAudioOutput audioOutput;
   QObject::connect(&player, &QAVPlayer::audioFrame, [&](const QAVAudioFrame &frame) { 
        // Access to the data
        qDebug() << autioFrame.format() << autioFrame.data().size();
        audioOutput.play(frame);
   });
   
   QObject::connect(&p, &QAVPlayer::subtitleFrame, &p, [](const QAVSubtitleFrame &frame) {
        for (unsigned i = 0; i < frame.subtitle()->num_rects; ++i) {
            if (frame.subtitle()->rects[i]->type == SUBTITLE_TEXT)
                qDebug() << "text:" << frame.subtitle()->rects[i]->text;
            else
                qDebug() << "ass:" << frame.subtitle()->rects[i]->ass;
       }
   });
   

3. Each action is confirmed by a signal:

   // All signals are added to a queue and guaranteed to be emitted in proper order.
   QObject::connect(&player, &QAVPlayer::played, [&](qint64 pos) { qDebug() << "Playing started from pos" << pos;  });
   QObject::connect(&player, &QAVPlayer::paused, [&](qint64 pos) { qDebug() << "Paused at pos" << pos; });
   QObject::connect(&player, &QAVPlayer::stopped, [&](qint64 pos) { qDebug() << "Stopped at pos" << pos; });
   QObject::connect(&player, &QAVPlayer::seeked, [&](qint64 pos) { qDebug() << "Seeked to pos" << pos; });
   QObject::connect(&player, &QAVPlayer::stepped, [&](qint64 pos) { qDebug() << "Made a step to pos" << pos; });
   QObject::connect(&player, &QAVPlayer::mediaStatusChanged, [&](QAVPlayer::MediaStatus status) { 
       switch (status) {
           case QAVplayer::EndOfMedia:
               qDebug() << "Finished to play, no frames in queue"; 
               break;
           case QAVplayer::NoMedia:
               qDebug() << "Demuxer threads are finished";
               break;
           default:
               break;
          }
    });
   

4. Accurate seek:

   QObject::connect(&p, &QAVPlayer::seeked, &p, [&](qint64 pos) { seekPosition = pos; });
   QObject::connect(&player, &QAVPlayer::videoFrame, [&](const QAVVideoFrame &frame) { seekFrame = frame; });
   player.seek(5000)
   QTRY_COMPARE(seekPosition, 5000);
   QTRY_COMPARE(seekFrame.pts(), 5.0);
   

   If there is a frame with needed pts, it will be returned as first frame.

5. FFmpeg filters:

   player.setFilter("crop=iw/2:ih:0:0,split[left][tmp];[tmp]hflip[right];[left][right] hstack");
   // Render bundled subtitles
   player.setFilter("subtitles=file.mkv");
   // Render subtitles from srt file
   player.setFilter("subtitles=file.srt");
   // Multiple filters
   player.setFilters({
        "drawtext=text=%{pts\\\\:hms}:x=(w-text_w)/2:y=(h-text_h)*(4/5):box=1:[email protected]:fontsize=36[drawtext]",
        "negate[negate]",
        "[0:v]split=3[in1][in2][in3];[in1]boxblur[out1];[in2]negate[out2];[in3]drawtext=text=%{pts\\\\:hms}:x=(w-text_w)/2:y=(h-text_h)*(4/5):box=1:[email protected]:fontsize=36[out3]"
   }); // Return frames from 3 filters with 5 outputs
   

6. Step by step:

   // Pausing will always emit one frame
   QObject::connect(&player, &QAVPlayer::videoFrame, [&](const QAVVideoFrame &frame) { receivedFrame = frame; });
   if (player.state() != QAVPlayer::PausedState) { // No frames if it is already paused
       player.pause();
       QTRY_VERIFY(receivedFrame);
   }
   
   // Always makes a step forward and emits only one frame
   player.stepForward();
   // the same here but backward
   player.stepBackward();
   

7. Multiple streams:

   qDebug() << "Audio streams" << player.availableAudioStreams().size();
   qDebug() << "Current audio stream" << player.currentAudioStreams().first().index() << player.currentAudioStreams().first().metadata();
   player.setAudioStreams(player.availableAudioStreams()); // Return all frames for all available audio streams      
   

8. HW accelerations:

   QT_AVPLAYER_NO_HWDEVICE can be used to force using software decoding. The video codec is negotiated automatically.

9. QtMultimedia could be used to render video frames to QML or Widgets. See examples.

10. Qt 5.12 - 6.x is supported

Build

Linux:

cmake:

cd build; /opt/cmake-3.19.2/bin/cmake .. -DCMAKE_PREFIX_PATH=/opt/dev/qtbase/lib/cmake/Qt5 -DCMAKE_INSTALL_PREFIX=/opt/QtAVPlayer/install -DCMAKE_LIBRARY_PATH="/opt/dev/qtbase/lib;/opt/ffmpeg/install/lib" -DCMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES=/opt/ffmpeg/install/include

qmake:

Install ffmpeg visible with pkg-config.

$ cd QtAVPlayer && qmake && make -j8

macOS and iOS:

$ export FFMPEG_ROOT=/usr/local/Cellar/ffmpeg/4.3_1
$ export LIBRARY_PATH=$FFMPEG_ROOT/lib:$LIBRARY_PATH
$ export CPLUS_INCLUDE_PATH=$FFMPEG_ROOT/include:$CPLUS_INCLUDE_PATH
$ cd QtAVPlayer && qmake && make -j8    

Android:

Set vars that point to libraries in armeabi-v7a, arm64-v8a, x86 and x86_64 target archs.

$ export AVPLAYER_ANDROID_LIB_ARMEABI_V7A=/opt/mobile-ffmpeg/prebuilt/android-arm/ffmpeg/lib
$ export AVPLAYER_ANDROID_LIB_ARMEABI_V8A=/opt/mobile-ffmpeg/prebuilt/android-arm64/ffmpeg/lib
$ export AVPLAYER_ANDROID_LIB_X86=/opt/mobile-ffmpeg/prebuilt/android-x86/ffmpeg/lib
$ export AVPLAYER_ANDROID_LIB_X86_64=/opt/mobile-ffmpeg/prebuilt/android-x86_64/ffmpeg/lib
$ export CPLUS_INCLUDE_PATH=/opt/mobile-ffmpeg/prebuilt/android-arm64/ffmpeg/include:$CPLUS_INCLUDE_PATH
$ cd QtAVPlayer && qmake && make -j8

Don't forget to set extra libs in pro file for your app:

ANDROID_EXTRA_LIBS += /opt/mobile-ffmpeg/prebuilt/android-arm/ffmpeg/lib/libavdevice.so /opt/mobile-ffmpeg/prebuilt/android-arm/ffmpeg/lib/libavformat.so /opt/mobile-ffmpeg/prebuilt/android-arm/ffmpeg/lib/libavutil.so /opt/mobile-ffmpeg/prebuilt/android-arm/ffmpeg/lib/libavcodec.so /opt/mobile-ffmpeg/prebuilt/android-arm/ffmpeg/lib/libavfilter.so /opt/mobile-ffmpeg/prebuilt/android-arm/ffmpeg/lib/libswscale.so /opt/mobile-ffmpeg/prebuilt/android-arm/ffmpeg/lib/libswresample.so

Windows and MSVC:

cmake:

cd build
cmake .. -DCMAKE_PREFIX_PATH=c:\dev\qtbase\lib\cmake\Qt5 -DCMAKE_LIBRARY_PATH="c:\dev\qtbase\lib;c:\ffmpeg\lib" -DCMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES=c:\ffmpeg\include -DCMAKE_INSTALL_PREFIX=c:\QtAVPlayer\install
msbuild QtAVPlayer.sln
cmake --build . --target install

qmake:

SET FFMPEG=C:\ffmpeg
SET PATH=%FFMPEG%\lib;%PATH%
SET INCLUDE=%FFMPEG%\include;%INCLUDE%
SET LIB=%FFMPEG%\lib;%LIB%
cd QtAVPlayer && qmake && nmake