qmediaplayer.cpp

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qmediaplayer_p.h"
 
#include <private/qmultimediautils_p.h>
#include <private/qplatformmediaintegration_p.h>
#include <private/qaudiobufferoutput_p.h>
#include <qvideosink.h>
#include <qaudiooutput.h>
 
#include <QtCore/qcoreevent.h>
#include <QtCore/qmetaobject.h>
#include <QtCore/qtimer.h>
#include <QtCore/qdebug.h>
#include <QtCore/qdir.h>
#include <QtCore/qpointer.h>
#include <QtCore/qfileinfo.h>
#include <QtCore/qtemporaryfile.h>
#include <QtCore/qcoreapplication.h>
 
#if defined(Q_OS_ANDROID)
#  include <QtCore/qjniobject.h>
#endif
 
QT_BEGIN_NAMESPACE
 
/*!
    \class QMediaPlayer
    \brief The QMediaPlayer class allows the playing of a media files.
    \inmodule QtMultimedia
    \ingroup multimedia
    \ingroup multimedia_playback
    \ingroup multimedia_video
 
    The QMediaPlayer class is a high level media playback class. It can be used
    to playback audio of video media files. The content
    to playback is specified as a QUrl object.
 
    \snippet multimedia-snippets/media.cpp Player
 
    QVideoWidget can be used with QMediaPlayer for video rendering.
 
    \sa QVideoWidget
*/
 
/*!
    \qmltype MediaPlayer
    \nativetype QMediaPlayer
    \brief Adds media playback to a scene.
 
    \inqmlmodule QtMultimedia
    \ingroup multimedia_qml
    \ingroup multimedia_audio_qml
    \ingroup multimedia_video_qml
 
    \qml
    Text {
        text: "Click Me!";
        font.pointSize: 24;
        width: 150; height: 50;
 
        MediaPlayer {
            id: playMusic
            source: "music.wav"
            audioOutput: AudioOutput {}
        }
        MouseArea {
            anchors.fill: parent
            onPressed:  { playMusic.play() }
        }
    }
    \endqml
 
    You can use MediaPlayer together with a MultiMedia::AudioOutput to play audio content, or you can use it
    in conjunction with a Multimedia::VideoOutput for rendering video.
 
    \qml
    Item {
        MediaPlayer {
            id: mediaplayer
            source: "groovy_video.mp4"
            audioOutput: AudioOutput {}
            videoOutput: videoOutput
        }
 
        VideoOutput {
            id: videoOutput
            anchors.fill: parent
        }
 
        MouseArea {
            anchors.fill: parent
            onPressed: mediaplayer.play();
        }
    }
    \endqml
 
    \sa AudioOutput, VideoOutput
*/
 
void QMediaPlayerPrivate::setState(QMediaPlayer::PlaybackState toState)
{
    Q_Q(QMediaPlayer);
 
    if (toState != state) {
        const auto fromState = std::exchange(state, toState);
        if (toState == QMediaPlayer::PlayingState || fromState == QMediaPlayer::PlayingState)
            emit q->playingChanged(toState == QMediaPlayer::PlayingState);
        emit q->playbackStateChanged(toState);
    }
}
 
void QMediaPlayerPrivate::setStatus(QMediaPlayer::MediaStatus s)
{
    Q_Q(QMediaPlayer);
 
    emit q->mediaStatusChanged(s);
}
 
void QMediaPlayerPrivate::setError(QMediaPlayer::Error error, const QString &errorString)
{
    Q_Q(QMediaPlayer);
 
    this->error.setAndNotify(error, errorString, *q);
}
 
void QMediaPlayerPrivate::setMedia(QUrl media, QIODevice *stream)
{
    setError(QMediaPlayer::NoError, {});
 
    if (!control)
        return;
 
    media = m_sourceResolver->resolve(media);
 
    auto setErrorFn = [&](
        QMediaPlayer::MediaStatus status,
        QMediaPlayer::Error err,
        const QString &errString)
    {
        control->setMedia(QUrl(), nullptr);
        control->mediaStatusChanged(status);
        control->error(err, errString);
    };
 
    std::unique_ptr<QFile> file;
 
    // Back ends can't play qrc files directly.
    // If the back end supports StreamPlayback, we pass a QFile for that resource.
    // If it doesn't, we copy the data to a temporary file and pass its path.
    if (!media.isEmpty() && !stream && media.scheme() == QLatin1String("qrc")
        && !control->canPlayQrc()) {
        qrcMedia = media;
 
        file.reset(new QFile(QLatin1Char(':') + media.path()));
        if (!file->open(QFile::ReadOnly)) {
            file.reset();
            setErrorFn(
                QMediaPlayer::InvalidMedia,
                QMediaPlayer::ResourceError,
                QMediaPlayer::tr("Attempting to play invalid Qt resource"));
 
        } else if (control->streamPlaybackSupported()) {
            control->setMedia(media, file.get());
        } else {
#if QT_CONFIG(temporaryfile)
#if defined(Q_OS_ANDROID)
            QString tempFileName = QDir::tempPath() + media.path();
            QDir().mkpath(QFileInfo(tempFileName).path());
            std::unique_ptr<QTemporaryFile> tempFile { QTemporaryFile::createNativeFile(*file) };
            if (tempFile.get() == nullptr) {
                setErrorFn(
                    QMediaPlayer::InvalidMedia,
                    QMediaPlayer::ResourceError,
                    QMediaPlayer::tr("Failed to establish temporary file during playback"));
                return;
            }
            if (!tempFile->rename(tempFileName)) {
                setErrorFn(
                    QMediaPlayer::InvalidMedia,
                    QMediaPlayer::ResourceError,
                    QStringLiteral("Could not rename temporary file to: %1").arg(tempFileName));
                return;
            }
#else
            std::unique_ptr<QTemporaryFile> tempFile = std::make_unique<QTemporaryFile>();
 
            // Preserve original file extension, some back ends might not load the file if it doesn't
            // have an extension.
            const QString suffix = QFileInfo(*file).suffix();
            if (!suffix.isEmpty())
                tempFile->setFileTemplate(tempFile->fileTemplate() + QLatin1Char('.') + suffix);
 
            // Copy the qrc data into the temporary file
            if (!tempFile->open()) {
                setErrorFn(
                    QMediaPlayer::InvalidMedia,
                    QMediaPlayer::ResourceError,
                    tempFile->errorString());
                qrcFile.reset();
                return;
            }
            char buffer[4096];
            while (true) {
                qint64 len = file->read(buffer, sizeof(buffer));
                if (len < 1)
                    break;
                tempFile->write(buffer, len);
            }
            tempFile->close();
#endif
            file = std::move(tempFile);
            control->setMedia(QUrl(QUrl::fromLocalFile(file->fileName())), nullptr);
#else
            qWarning("Qt was built with -no-feature-temporaryfile: playback from resource file is not supported!");
#endif
        }
    } else {
        qrcMedia = QUrl();
        QUrl url = qMediaFromUserInput(media);
        if (url.scheme() == QLatin1String("content") && !stream) {
            file.reset(new QFile(media.url()));
            stream = file.get();
        }
 
        control->setMedia(url, stream);
    }
 
    qrcFile.swap(file); // Cleans up any previous file
}
 
QList<QMediaMetaData> QMediaPlayerPrivate::trackMetaData(QPlatformMediaPlayer::TrackType s) const
{
    QList<QMediaMetaData> tracks;
    if (control) {
        int count = control->trackCount(s);
        for (int i = 0; i < count; ++i) {
            tracks.append(control->trackMetaData(s, i));
        }
    }
    return tracks;
}
 
/*!
    Constructs a QMediaPlayer instance as a child of \a{parent}.
*/
 
QMediaPlayer::QMediaPlayer(QObject *parent)
    : QObject(*new QMediaPlayerPrivate, parent)
{
    Q_D(QMediaPlayer);
 
    auto maybeControl = QPlatformMediaIntegration::instance()->createPlayer(this);
    if (maybeControl) {
        d->control = maybeControl.value();
        d->state = d->control->state();
    } else {
        qWarning() << "Failed to initialize QMediaPlayer" << maybeControl.error();
        d->setError(QMediaPlayer::ResourceError, maybeControl.error());
    }
}
 
 
/*!
    Destroys the player object.
*/
 
QMediaPlayer::~QMediaPlayer()
{
    Q_D(QMediaPlayer);
 
    // prevents emitting audioOutputChanged and videoOutputChanged.
    QSignalBlocker blocker(this);
 
    // Reset audio output and video sink to ensure proper unregistering of the source
    // To be investigated: registering of the source might be removed after switching on the ffmpeg
    // backend;
 
    // Workaround to prevent freeze in GStreamer when setting audioOutput while stopped
    if (d->control)
        d->control->qmediaplayerDestructorCalled = true;
    setAudioOutput(nullptr);
 
    d->setVideoSink(nullptr);
    delete d->control;
}
 
QUrl QMediaPlayer::source() const
{
    Q_D(const QMediaPlayer);
 
    return d->source;
}
 
/*!
    Returns the stream source of media data.
 
    This is only valid if a stream was passed to setSource().
 
    \sa setSource()
*/
 
const QIODevice *QMediaPlayer::sourceDevice() const
{
    Q_D(const QMediaPlayer);
 
    return d->stream;
}
 
/*!
    \property QMediaPlayer::playbackState
 
    Returns the \l{QMediaPlayer::}{PlaybackState}.
 
    \sa playing
*/
QMediaPlayer::PlaybackState QMediaPlayer::playbackState() const
{
    Q_D(const QMediaPlayer);
 
    // In case if EndOfMedia status is already received
    // but state is not.
    if (d->control
        && d->control->mediaStatus() == QMediaPlayer::EndOfMedia
        && d->state != d->control->state()) {
        return d->control->state();
    }
 
    return d->state;
}
 
QMediaPlayer::MediaStatus QMediaPlayer::mediaStatus() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->mediaStatus() : NoMedia;
}
 
/*!
    Returns the duration of the current media in ms.
 
    Returns 0 if the media player doesn't have a valid media file or stream.
    For live streams, the duration usually changes during playback as more
    data becomes available.
*/
qint64 QMediaPlayer::duration() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->duration() : 0;
}
 
/*!
    Returns the current position inside the media being played back in ms.
 
    Returns 0 if the media player doesn't have a valid media file or stream.
    For live streams, the duration usually changes during playback as more
    data becomes available.
*/
qint64 QMediaPlayer::position() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->position() : 0;
}
 
/*!
    Returns a number between 0 and 1 when buffering data.
 
    0 means that there is no buffered data available, playback is usually
    stalled in this case. Playback will resume once the buffer reaches 1,
    meaning enough data has been buffered to be able to resume playback.
 
    bufferProgress() will always return 1 for local files.
*/
float QMediaPlayer::bufferProgress() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->bufferProgress() : 0;
}
 
/*!
    Returns a QMediaTimeRange describing the currently buffered data.
 
    When streaming media from a remote source, different parts of the media
    file can be available locally. The returned QMediaTimeRange object describes
    the time ranges that are buffered and available for immediate playback.
 
    \sa QMediaTimeRange
*/
QMediaTimeRange QMediaPlayer::bufferedTimeRange() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->availablePlaybackRanges() : QMediaTimeRange{};
}
 
/*!
    \qmlproperty bool QtMultimedia::MediaPlayer::hasAudio
 
    This property holds whether the media contains audio.
*/
 
/*!
    \property QMediaPlayer::hasAudio
    \brief This property holds whether the media contains audio.
*/
bool QMediaPlayer::hasAudio() const
{
    Q_D(const QMediaPlayer);
    return d->control && d->control->isAudioAvailable();
}
 
/*!
    \qmlproperty bool QtMultimedia::MediaPlayer::hasVideo
 
    This property holds whether the media contains video.
*/
 
/*!
    \property QMediaPlayer::hasVideo
    \brief This property holds whether the media contains video.
*/
bool QMediaPlayer::hasVideo() const
{
    Q_D(const QMediaPlayer);
    return d->control && d->control->isVideoAvailable();
}
 
/*!
    Returns true if the media is seekable. Most file based media files are seekable,
    but live streams usually are not.
 
    \sa position
*/
bool QMediaPlayer::isSeekable() const
{
    Q_D(const QMediaPlayer);
    return d->control && d->control->isSeekable();
}
 
bool QMediaPlayer::isPlaying() const
{
    Q_D(const QMediaPlayer);
    return d->state == QMediaPlayer::PlayingState;
}
 
/*!
    Returns the current playback rate.
*/
qreal QMediaPlayer::playbackRate() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->playbackRate() : 0.;
}
 
/*!
    \enum QMediaPlayer::Loops
 
    Some predefined constants for the \l loops property.
 
    \value Infinite Loop forever.
    \value Once Play the media once (the default).
*/
 
/*!
    \property QMediaPlayer::loops
 
    Determines how often the media is played before the player stops.
    Set to QMediaPlayer::Infinite to loop the current media file forever.
 
    The default value is \c 1. Setting this property to \c 0 has no effect.
*/
 
/*!
    \qmlproperty int QtMultimedia::MediaPlayer::loops
 
    Determines how often the media is played before the player stops.
    Set to MediaPlayer::Infinite to loop the current media file forever.
 
    The default value is \c 1. Setting this property to \c 0 has no effect.
*/
int QMediaPlayer::loops() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->loops() : 1;
}
 
void QMediaPlayer::setLoops(int loops)
{
    Q_D(QMediaPlayer);
    if (loops == 0)
        return;
    if (d->control)
        d->control->setLoops(loops);
}
 
/*!
    Returns the current error state.
*/
QMediaPlayer::Error QMediaPlayer::error() const
{
    return d_func()->error.code();
}
 
/*!
    \qmlproperty string QtMultimedia::MediaPlayer::errorString
 
    This property holds a string describing the current error condition in more
    detail.
*/
 
/*!
    \property QMediaPlayer::errorString
    \brief This property holds a string describing the current error condition in
    more detail.
*/
QString QMediaPlayer::errorString() const
{
    return d_func()->error.description();
}
 
/*!
    \qmlmethod void QtMultimedia::MediaPlayer::play()
 
    Starts or resumes playback of the media.
 
    Sets the \l playbackState property to PlayingState, and changes
    \l playing to \c true.
*/
 
/*!
    Start or resume playing the current source.
 
    \sa pause(), stop()
*/
void QMediaPlayer::play()
{
    Q_D(QMediaPlayer);
 
    if (!d->control)
        return;
 
    d->control->play();
}
 
/*!
    \qmlmethod void QtMultimedia::MediaPlayer::pause()
 
    Pauses playback of the media.
 
    Sets the \l playbackState property to PausedState,
    and changes \l playing to \c false.
*/
 
/*!
    Pause playing the current source.
 
    \sa play(), stop()
*/
void QMediaPlayer::pause()
{
    Q_D(QMediaPlayer);
 
    if (d->control)
        d->control->pause();
}
 
/*!
    \qmlmethod void QtMultimedia::MediaPlayer::stop()
 
    Stops playback of the media.
 
    Sets the \l playbackState property to StoppedState,
    and changes \l playing to \c false.
*/
 
/*!
    Stop playing, and reset the play position to the beginning.
 
    \sa play(), pause()
*/
void QMediaPlayer::stop()
{
    Q_D(QMediaPlayer);
 
    if (d->control)
        d->control->stop();
}
 
void QMediaPlayer::setPosition(qint64 position)
{
    Q_D(QMediaPlayer);
 
    if (!d->control)
        return;
    if (!d->control->isSeekable())
        return;
    d->control->setPosition(qMax(position, 0ll));
}
 
void QMediaPlayer::setPlaybackRate(qreal rate)
{
    Q_D(QMediaPlayer);
 
    if (d->control)
        d->control->setPlaybackRate(rate);
}
 
/*!
    \qmlproperty url QtMultimedia::MediaPlayer::source
 
    This property holds the source URL of the media.
 
    \snippet multimedia-snippets/qtvideosink.qml complete
 
    \sa QMediaPlayer::setSource()
*/
 
/*!
    Sets the current \a source.
 
    Setting the media to a null QUrl will cause the player to discard all
    information relating to the current media source and to cease all I/O operations related
    to that media. Setting the media will stop the playback.
 
    \note This function returns immediately after recording the specified source of the media.
    It does not wait for the media to finish loading and does not check for errors. Listen for
    the mediaStatusChanged() and error() signals to be notified when the media is loaded and
    when an error occurs during loading.
 
    \note FFmpeg, used by the FFmpeg media backend, restricts use of nested protocols for
    security reasons. In controlled environments where all inputs are trusted, the list of
    approved protocols can be overridden using the QT_FFMPEG_PROTOCOL_WHITELIST environment
    variable. This environment variable is Qt's private API and can change between patch
    releases without notice.
*/
 
void QMediaPlayer::setSource(const QUrl &source)
{
    Q_D(QMediaPlayer);
    stop();
 
    if (d->source == source && d->stream == nullptr)
        return;
 
    d->source = source;
    d->stream = nullptr;
 
    d->setMedia(source, nullptr);
    emit sourceChanged(d->source);
}
 
/*!
    Sets the current source \a device.
 
    The media data will be read from \a device. The \a sourceUrl can be provided
    to resolve additional information about the media, mime type etc. The
    \a device must be open and readable.
 
    For macOS the \a device should also be seek-able.
 
    \note This function returns immediately after recording the specified source
    of the media. It does not wait for the media to finish loading and does not
    check for errors. Listen for the mediaStatusChanged() and error() signals to
    be notified when the media is loaded, and if an error occurs during loading.
*/
void QMediaPlayer::setSourceDevice(QIODevice *device, const QUrl &sourceUrl)
{
    Q_D(QMediaPlayer);
    stop();
 
    if (d->source == sourceUrl && d->stream == device)
        return;
 
    d->source = sourceUrl;
    d->stream = device;
 
    d->setMedia(d->source, device);
    emit sourceChanged(d->source);
}
 
/*!
    \qmlproperty QAudioBufferOutput QtMultimedia::MediaPlayer::audioBufferOutput
    \since 6.8
 
    This property holds the target audio buffer output.
 
    Normal usage of MediaPlayer from QML should not require using this property.
 
    \sa QMediaPlayer::audioBufferOutput()
*/
 
/*!
    \property QMediaPlayer::audioBufferOutput
    \since 6.8
    \brief The output audio buffer used by the media player.
 
    Sets an audio buffer \a output to the media player.
 
    If \l QAudioBufferOutput is specified and the media source
    contains an audio stream, the media player, it will emit
    the signal \l{QAudioBufferOutput::audioBufferReceived} with
    audio buffers containing decoded audio data. At the end of
    the audio stream, \c QMediaPlayer emits an empty \l QAudioBuffer.
 
    \c QMediaPlayer emits outputs audio buffers at the same time as it
    pushes the matching data to the audio output if it's specified.
    However, the sound can be played with a small delay due to
    audio bufferization.
 
    The format of emitted audio buffers is taken from the
    specified \a output or from the matching audio stream
    if the \a output returns an invalid format. Emitted
    audio data is not scaled depending on the current playback rate.
 
    Potential use cases of utilizing \c QAudioBufferOutput
    with \c QMediaPlayer might be:
    \list
    \li Audio visualization. If the playback rate of the media player
    is not \c 1, you may scale the output image dimensions,
    or image update interval according to the requirements
    of the visualizer.
    \li Any AI sound processing, e.g. voice recognition.
    \li Sending the data to external audio output.
    Playback rate changing, synchronization with video, and manual
    flushing on stoping and seeking should be considered.
    We don't recommend using the audio buffer output
    for this purpose unless you have a strong reason for this.
    \endlist
 
*/
void QMediaPlayer::setAudioBufferOutput(QAudioBufferOutput *output)
{
    Q_D(QMediaPlayer);
 
    QAudioBufferOutput *oldOutput = d->audioBufferOutput;
    if (oldOutput == output)
        return;
 
    d->audioBufferOutput = output;
 
    if (oldOutput) {
        auto oldPlayer = QAudioBufferOutputPrivate::exchangeMediaPlayer(*oldOutput, this);
        if (oldPlayer)
            oldPlayer->setAudioBufferOutput(nullptr);
    }
 
    if (d->control)
        d->control->setAudioBufferOutput(output);
 
    emit audioBufferOutputChanged();
}
 
QAudioBufferOutput *QMediaPlayer::audioBufferOutput() const
{
    Q_D(const QMediaPlayer);
    return d->audioBufferOutput;
}
 
/*!
    \qmlproperty AudioOutput QtMultimedia::MediaPlayer::audioOutput
 
    This property holds the target audio output.
    Accepts one AudioOutput elements.
 
    \sa QMediaPlayer::setAudioOutput()
*/
 
 
/*!
    \property QMediaPlayer::audioOutput
    \brief The audio output device used by the media player.
 
    The current audio output to be used when playing back media. Setting
    a new audio output will replace the currently used output.
 
    Setting this property to \c nullptr will disable any audio output.
*/
void QMediaPlayer::setAudioOutput(QAudioOutput *output)
{
    Q_D(QMediaPlayer);
    auto oldOutput = d->audioOutput;
    if (oldOutput == output)
        return;
    d->audioOutput = output;
    if (d->control)
        d->control->setAudioOutput(nullptr);
    if (oldOutput)
        oldOutput->setDisconnectFunction({});
    if (output) {
        output->setDisconnectFunction([this](){ setAudioOutput(nullptr); });
        if (d->control)
            d->control->setAudioOutput(output->handle());
    }
    emit audioOutputChanged();
}
 
QAudioOutput *QMediaPlayer::audioOutput() const
{
    Q_D(const QMediaPlayer);
    return d->audioOutput;
}
 
/*!
    \qmlproperty list<mediaMetaData> QtMultimedia::MediaPlayer::audioTracks
 
    This property holds a list of metadata.
    Each index refers to an audio track.
 
    The metadata holds properties describing the individual tracks. For
    audio tracks the \l{QMediaMetaData}{Language} is usually the most
    important property.
 
    \sa mediaMetaData
*/
 
/*!
    \property QMediaPlayer::audioTracks
 
    Lists the set of available audio tracks inside the media.
 
    The QMediaMetaData returned describes the properties of individual
    tracks.
 
    Different audio tracks can for example contain audio in different languages.
*/
QList<QMediaMetaData> QMediaPlayer::audioTracks() const
{
    Q_D(const QMediaPlayer);
    return d->trackMetaData(QPlatformMediaPlayer::AudioStream);
}
 
/*!
    \qmlproperty list<mediaMetaData> QtMultimedia::MediaPlayer::videoTracks
 
    This property holds a list of metadata.
    Each index refers to a video track.
 
    The metadata holds properties describing the individual tracks.
 
    \sa mediaMetaData
*/
 
/*!
    \property QMediaPlayer::videoTracks
 
    Lists the set of available video tracks inside the media.
 
    The QMediaMetaData returned describes the properties of individual
    tracks.
*/
QList<QMediaMetaData> QMediaPlayer::videoTracks() const
{
    Q_D(const QMediaPlayer);
    return d->trackMetaData(QPlatformMediaPlayer::VideoStream);
}
 
/*!
    \qmlproperty list<mediaMetaData> QtMultimedia::MediaPlayer::subtitleTracks
 
    This property holds a list of metadata.
    Each index refers to a subtitle track.
 
    The metadata holds properties describing the individual tracks. For
    subtitle tracks the \l{QMediaMetaData}{Language} is usually the most
    important property.
 
    \sa mediaMetaData
*/
 
/*!
    \property QMediaPlayer::subtitleTracks
 
    Lists the set of available subtitle tracks inside the media.
 
    The QMediaMetaData returned describes the properties of individual
    tracks.
*/
QList<QMediaMetaData> QMediaPlayer::subtitleTracks() const
{
    Q_D(const QMediaPlayer);
    return d->trackMetaData(QPlatformMediaPlayer::SubtitleStream);
}
 
/*!
    \qmlproperty int QtMultimedia::MediaPlayer::activeAudioTrack
 
    This property holds the track number of the currently active audio track.
    Set to \c{-1} to disable audio track.
 
    The default property value is \c{0}: the first audio track.
*/
 
/*!
    \property QMediaPlayer::activeAudioTrack
    \brief Returns the currently active audio track.
 
    By default, the first available audio track will be chosen.
 
    Set \a index to \c -1 to disable all audio tracks.
*/
int QMediaPlayer::activeAudioTrack() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->activeTrack(QPlatformMediaPlayer::AudioStream) : 0;
}
 
/*!
    \since 6.2
    \qmlproperty int QtMultimedia::MediaPlayer::activeVideoTrack
 
    This property holds the track number of the currently active video audio track.
    Set to \c{-1} to disable video track.
 
    The default property value is \c{0}: the first video track.
*/
 
/*!
    \property QMediaPlayer::activeVideoTrack
    \brief Returns the currently active video track.
 
    By default, the first available audio track will be chosen.
 
    Set \a index to \c -1 to disable all video tracks.
*/
int QMediaPlayer::activeVideoTrack() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->activeTrack(QPlatformMediaPlayer::VideoStream) : -1;
}
 
/*!
    \since 6.2
    \qmlproperty int QtMultimedia::MediaPlayer::activeSubtitleTrack
 
    This property holds the track number of the currently active subtitle track.
    Set to \c{-1} to disable subtitle track.
 
    The default property value is \c{-1}: no subtitles active.
*/
 
/*!
    \property QMediaPlayer::activeSubtitleTrack
    \brief Returns the currently active subtitle track.
 
    Set \a index to \c -1 to disable subtitles.
 
    Subtitles are disabled by default.
*/
int QMediaPlayer::activeSubtitleTrack() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->activeTrack(QPlatformMediaPlayer::SubtitleStream) : -1;
}
 
void QMediaPlayer::setActiveAudioTrack(int index)
{
    Q_D(QMediaPlayer);
    if (!d->control)
        return;
 
    if (activeAudioTrack() == index)
        return;
    d->control->setActiveTrack(QPlatformMediaPlayer::AudioStream, index);
}
 
void QMediaPlayer::setActiveVideoTrack(int index)
{
    Q_D(QMediaPlayer);
    if (!d->control)
        return;
 
    if (activeVideoTrack() == index)
        return;
    d->control->setActiveTrack(QPlatformMediaPlayer::VideoStream, index);
}
 
void QMediaPlayer::setActiveSubtitleTrack(int index)
{
    Q_D(QMediaPlayer);
    if (!d->control)
        return;
 
    if (activeSubtitleTrack() == index)
        return;
    d->control->setActiveTrack(QPlatformMediaPlayer::SubtitleStream, index);
}
 
/*!
    \qmlproperty VideoOutput QtMultimedia::MediaPlayer::videoOutput
 
    This property holds the target video output.
    Accepts one VideoOutput elements.
 
    \sa QMediaPlayer::setVideoOutput()
*/
 
/*!
    \property QMediaPlayer::videoOutput
    \brief The video output to be used by the media player.
 
    A media player can only have one video output attached, so
    setting this property will replace the previously connected
    video output.
 
    Setting this property to \c nullptr will disable video output.
*/
QObject *QMediaPlayer::videoOutput() const
{
    Q_D(const QMediaPlayer);
    return d->videoOutput;
}
 
void QMediaPlayer::setVideoOutput(QObject *output)
{
    Q_D(QMediaPlayer);
    if (d->videoOutput == output)
        return;
 
    auto *sink = qobject_cast<QVideoSink *>(output);
    if (!sink && output) {
        auto *mo = output->metaObject();
        mo->invokeMethod(output, "videoSink", Q_RETURN_ARG(QVideoSink *, sink));
    }
    d->videoOutput = output;
    d->setVideoSink(sink);
}
 
/*!
    Sets \a sink to be the QVideoSink instance to
    retrieve video data.
*/
void QMediaPlayer::setVideoSink(QVideoSink *sink)
{
    Q_D(QMediaPlayer);
    d->videoOutput = nullptr;
    d->setVideoSink(sink);
}
 
/*!
    Returns the QVideoSink instance.
*/
QVideoSink *QMediaPlayer::videoSink() const
{
    Q_D(const QMediaPlayer);
    return d->videoSink;
}
 
 
#if 0
/*
    \since 5.15
    Sets multiple video sinks as the video output of a media player.
    This allows the media player to render video frames on several outputs.
 
    If a video output has already been set on the media player the new surfaces
    will replace it.
*/
void QMediaPlayer::setVideoOutput(const QList<QVideoSink *> &sinks)
{
    // ### IMPLEMENT ME
    Q_UNUSED(sinks);
//    setVideoOutput(!surfaces.empty() ? new QVideoSurfaces(surfaces, this) : nullptr);
}
#endif
 
/*!
    Returns true if the media player is supported on this platform.
*/
bool QMediaPlayer::isAvailable() const
{
    Q_D(const QMediaPlayer);
    return bool(d->control);
}
 
/*!
    \qmlproperty mediaMetaData QtMultimedia::MediaPlayer::metaData
 
    Returns meta data for the current media used by the media player.
 
    Meta data can contain information such as the title of the video or its creation date.
 
    \note The Windows implementation provides metadata only for media located on the local file
    system.
*/
 
/*!
    \property QMediaPlayer::metaData
 
    Returns meta data for the current media used by the media player.
 
    Meta data can contain information such as the title of the video or its creation date.
 
    \note The Windows implementation provides metadata only for media located on the local file
    system.
*/
QMediaMetaData QMediaPlayer::metaData() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->metaData() : QMediaMetaData{};
}
 
/*!
    \qmlproperty bool QtMultimedia::MediaPlayer::pitchCompensation
    \since 6.10
 
    This property holds whether pitch compensation is enabled.
*/
 
/*!
    \property QMediaPlayer::pitchCompensation
    \brief The pitch compensation status of the media player.
    \since 6.10
 
    Indicates whether pitch compensation is enabled. When enabled, changing the playback rate
    will not affect the pitch of the audio signal.
 
    \note The pitch compensation will increase the CPU load of the QMediaPlayer.
 
    By default is \c{true} if pitch compensation, is available, else \c{false}.
*/
 
/*!
    Returns the state of pitch compensation.
    \since 6.10
*/
bool QMediaPlayer::pitchCompensation() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->pitchCompensation() : false;
}
 
/*!
    Sets the state (\a enabled or disabled) of pitch compensation. This only
    has an effect if the audio pitch compensation can be configured on the
    backend at runtime.
    \since 6.10
*/
void QMediaPlayer::setPitchCompensation(bool enabled) const
{
    Q_D(const QMediaPlayer);
    if (d->control)
        d->control->setPitchCompensation(enabled);
}
 
/*!
    \enum QMediaPlayer::PitchCompensationAvailability
    \since 6.10
 
    Availablility of pitch compensation.
 
    Different backends have different behavior regarding pitch compensation when changing
    playback rate.
 
    \value AlwaysOn The media player is always performing pitch compensation.
    \value Available The media player can be configured to use pitch compensation.
        If pitch compensation is available on the current platform, it will be enabled by default,
        but users can disable if needed.
    \value Unavailable The media player is not able to perform pitch compensation
        on the current platform.
*/
 
/*!
    \qmlproperty enumeration QtMultimedia::MediaPlayer::pitchCompensationAvailability
    \since 6.10
 
    Indicates the availability of pitch compensation of the \c MediaPlayer on the current backend.
    The enumeration \c PitchCompensationAvailability is scoped.
 
    \qmlenumeratorsfrom QMediaPlayer::PitchCompensationAvailability
*/
 
/*!
    \property QMediaPlayer::pitchCompensationAvailability
    \brief The pitch compensation availability of the current QtMultimedia backend.
    \since 6.10
 
    Indicates the availability of pitch compensation of the QMediaPlayer on the current backend.
 
    \note Different backends may have different behavior.
 
    For more information, see \l{QMediaPlayer::PitchCompensationAvailability}.
*/
 
/*!
    Returns availability of pitch compensation of the current backend.
    \since 6.10
*/
 
QMediaPlayer::PitchCompensationAvailability QMediaPlayer::pitchCompensationAvailability() const
{
    Q_D(const QMediaPlayer);
    return d->control ? d->control->pitchCompensationAvailability()
                      : PitchCompensationAvailability::Unavailable;
}
 
/*!
    \qmlproperty playbackOptions MediaPlayer::playbackOptions
    \since 6.10
 
    This property exposes the \l playbackOptions API that gives low-level control of media playback
    options. Although we strongly recommend to rely on the default settings of \l MediaPlayer,
    this API can be used to optimize media playback for specific use cases where the default
    options are not ideal.
 
    Playback options take effect the next time \l MediaPlayer::source is changed.
*/
 
/*!
    \property QMediaPlayer::playbackOptions
    \brief Advanced playback options used to configure media playback and decoding.
    \since 6.10
 
    This property exposes the \l QPlaybackOptions API that gives low-level control of media
    playback options. Although we strongly recommend to rely on the default settings of
    \l QMediaPlayer, this API can be used to optimize media playback for specific use cases where
    the default options are not ideal.
 
    Playback options take effect the next time \l QMediaPlayer::setSource() is called.
*/
 
QPlaybackOptions QMediaPlayer::playbackOptions() const
{
    Q_D(const QMediaPlayer);
    return d->playbackOptions;
}
 
void QMediaPlayer::setPlaybackOptions(const QPlaybackOptions &options)
{
    Q_D(QMediaPlayer);
    if (std::exchange(d->playbackOptions, options) != options)
        emit playbackOptionsChanged();
}
 
void QMediaPlayer::resetPlaybackOptions()
{
    Q_D(QMediaPlayer);
    QPlaybackOptions defaultOptions{ };
    if (std::exchange(d->playbackOptions, defaultOptions) != defaultOptions)
        emit playbackOptionsChanged();
}
 
// Enums
/*!
    \enum QMediaPlayer::PlaybackState
 
    Defines the current state of a media player.
 
    \value StoppedState The media player is not playing content, playback will begin from the start
    of the current track.
    \value PlayingState The media player is currently playing content. This indicates the same as the \l playing property.
    \value PausedState The media player has paused playback, playback of the current track will
    resume from the position the player was paused at.
*/
 
/*!
    \qmlproperty enumeration QtMultimedia::MediaPlayer::playbackState
 
    This property holds the state of media playback. It can be one of the following:
 
    \table
    \header \li Property value
            \li Description
    \row \li PlayingState
        \li The media is currently playing. This indicates the same as the \l playing property.
    \row \li PausedState
        \li Playback of the media has been suspended.
    \row \li StoppedState
        \li Playback of the media is yet to begin.
    \endtable
*/
 
/*!
    \qmlsignal QtMultimedia::MediaPlayer::playbackStateChanged()
 
    This signal is emitted when the \l playbackState property is altered.
*/
 
/*!
    \qmlsignal QtMultimedia::MediaPlayer::playingChanged()
 
    This signal is emitted when the \l playing property changes.
*/
 
/*!
    \enum QMediaPlayer::MediaStatus
 
    Defines the status of a media player's current media.
 
    \value NoMedia The is no current media.  The player is in the StoppedState.
    \value LoadingMedia The current media is being loaded. The player may be in any state.
    \value LoadedMedia The current media has been loaded. The player is in the StoppedState.
    \value StalledMedia Playback of the current media has stalled due to insufficient buffering or
    some other temporary interruption.  The player is in the PlayingState or PausedState.
    \value BufferingMedia The player is buffering data but has enough data buffered for playback to
    continue for the immediate future.  The player is in the PlayingState or PausedState.
    \value BufferedMedia The player has fully buffered the current media.  The player is in the
    PlayingState or PausedState.
    \value EndOfMedia Playback has reached the end of the current media.  The player is in the
    StoppedState.
    \value InvalidMedia The current media cannot be played.  The player is in the StoppedState.
*/
 
/*!
    \qmlproperty enumeration QtMultimedia::MediaPlayer::mediaStatus
 
    This property holds the status of media loading. It can be one of the following:
 
    \qmlenumeratorsfrom QMediaPlayer::MediaStatus
*/
 
/*!
    \qmlproperty enumeration QtMultimedia::MediaPlayer::error
 
    This property holds the error state of the audio. It can be one of the following.
 
    \qmlenumeratorsfrom QMediaPlayer::Error
*/
 
/*!
    \enum QMediaPlayer::Error
 
    Defines a media player error condition.
 
    \value NoError No error has occurred.
    \value ResourceError A media resource couldn't be resolved.
    \value FormatError The format of a media resource isn't (fully) supported.  Playback may still
    be possible, but without an audio or video component.
    \value NetworkError A network error occurred.
    \value AccessDeniedError There are not the appropriate permissions to play a media resource.
*/
 
/*!
    \qmlsignal QtMultimedia::MediaPlayer::errorOccurred(error, errorString)
 
    This signal is emitted when an \a error has occurred. The \a errorString
    parameter may contain more detailed information about the error.
 
    \sa QMediaPlayer::Error
*/
 
/*!
    \fn QMediaPlayer::errorOccurred(QMediaPlayer::Error error, const QString &errorString)
 
    Signals that an \a error condition has occurred, with \a errorString
    containing a description of the error.
 
    \sa errorString()
*/
 
/*!
    \fn QMediaPlayer::mediaStatusChanged(QMediaPlayer::MediaStatus status)
 
    Signals that the \a status of the current media has changed.
 
    \sa mediaStatus()
*/
 
/*!
    \fn void QMediaPlayer::sourceChanged(const QUrl &media);
 
    Signals that the media source has been changed to \a media.
*/
 
/*!
    \fn void QMediaPlayer::playbackRateChanged(qreal rate);
 
    Signals the playbackRate has changed to \a rate.
*/
 
/*!
    \fn void QMediaPlayer::seekableChanged(bool seekable);
 
    Signals the \a seekable status of the player object has changed.
*/
 
// Properties
/*!
    \property QMediaPlayer::error
    \brief a string describing the last error condition.
 
    \sa error()
*/
 
/*!
    \property QMediaPlayer::source
    \brief the active media source being used by the player object.
 
    The player object will use the QUrl for selection of the content to
    be played.
 
    By default this property has a null QUrl.
 
    Setting this property to a null QUrl will cause the player to discard all
    information relating to the current media source and to cease all I/O operations related
    to that media.
 
    \sa QUrl
*/
 
/*!
    \property QMediaPlayer::mediaStatus
    \brief the status of the current media stream.
 
    The stream status describes how the playback of the current stream is
    progressing.
 
    By default this property is QMediaPlayer::NoMedia
 
*/
 
/*!
    \qmlproperty int QtMultimedia::MediaPlayer::duration
 
    This property holds the duration of the media in milliseconds.
 
    If the media doesn't have a fixed duration (a live stream for example) this
    will be set to \c{0}.
*/
 
/*!
    \property QMediaPlayer::duration
    \brief the duration of the current media.
 
    The value is the total playback time in milliseconds of the current media.
    The value may change across the life time of the QMediaPlayer object and
    may not be available when initial playback begins, connect to the
    durationChanged() signal to receive status notifications.
*/
 
/*!
    \qmlproperty int QtMultimedia::MediaPlayer::position
 
    The value is the current playback position, expressed in milliseconds since
    the beginning of the media. Periodically changes in the position will be
    indicated with the positionChanged() signal.
 
    If the \l seekable property is true, this property can be set to milliseconds.
*/
 
/*!
    \property QMediaPlayer::position
    \brief the playback position of the current media.
 
    The value is the current playback position, expressed in milliseconds since
    the beginning of the media. Periodically changes in the position will be
    indicated with the positionChanged() signal.
 
    If the \l seekable property is true, this property can be set to milliseconds.
*/
 
/*!
    \qmlproperty real QtMultimedia::MediaPlayer::bufferProgress
 
    This property holds how much of the data buffer is currently filled,
    from \c 0.0 (empty) to \c 1.0 (full).
 
    Playback can start or resume only when the buffer is entirely filled.
    When the buffer is filled, \c MediaPlayer.Buffered is true.
    When buffer progress is between \c 0.0 and \c 1.0, \c MediaPlayer.Buffering
    is set to \c{true}.
 
    A value lower than \c 1.0 implies that the property \c MediaPlayer.StalledMedia
    is \c{true}.
 
    \sa mediaStatus
 */
 
/*!
    \property QMediaPlayer::bufferProgress
    \brief the percentage of the temporary buffer filled before playback begins or resumes, from
    \c 0. (empty) to \c 1. (full).
 
    When the player object is buffering; this property holds the percentage of
    the temporary buffer that is filled. The buffer will need to reach 100%
    filled before playback can start or resume, at which time mediaStatus() will return
    BufferedMedia or BufferingMedia. If the value is anything lower than \c 100, mediaStatus() will
    return StalledMedia.
 
    \sa mediaStatus()
*/
 
/*!
    \qmlproperty bool QtMultimedia::MediaPlayer::seekable
 
    This property holds whether the \l position of the media can be changed.
*/
 
/*!
    \property QMediaPlayer::seekable
    \brief the seek-able status of the current media
 
    If seeking is supported this property will be true; false otherwise. The
    status of this property may change across the life time of the QMediaPlayer
    object, use the seekableChanged signal to monitor changes.
*/
 
/*!
    \qmlproperty bool QtMultimedia::MediaPlayer::playing
    \since 6.5
 
    Indicates whether the media is currently playing.
 
    \sa playbackState
*/
 
/*!
    \property QMediaPlayer::playing
    \brief Whether the media is playing.
    \since 6.5
 
    \sa playbackState, PlayingState
*/
 
/*!
    \qmlproperty real QtMultimedia::MediaPlayer::playbackRate
 
    This property holds the rate at which media is played at as a multiple of
    the normal rate.
 
    For more information, see \l{QMediaPlayer::playbackRate}.
 
    Defaults to \c{1.0}.
*/
 
/*!
    \property QMediaPlayer::playbackRate
    \brief the playback rate of the current media.
 
    This value is a multiplier applied to the media's standard playback
    rate. By default this value is 1.0, indicating that the media is
    playing at the standard speed. Values higher than 1.0 will increase
    the playback speed, while values between 0.0 and 1.0 results in
    slower playback. Negative playback rates are not supported.
 
    Not all playback services support change of the playback rate. It is
    framework defined as to the status and quality of audio and video
    while fast forwarding or rewinding.
*/
 
/*!
    \fn void QMediaPlayer::durationChanged(qint64 duration)
 
    Signals the duration of the content has changed to \a duration, expressed in milliseconds.
*/
 
/*!
    \fn void QMediaPlayer::positionChanged(qint64 position)
 
    Signals the position of the content has changed to \a position, expressed in
    milliseconds.
*/
 
/*!
    \fn void QMediaPlayer::hasVideoChanged(bool videoAvailable)
 
    Signals the availability of visual content has changed to \a videoAvailable.
*/
 
/*!
    \fn void QMediaPlayer::hasAudioChanged(bool available)
 
    Signals the availability of audio content has changed to \a available.
*/
 
/*!
    \fn void QMediaPlayer::bufferProgressChanged(float filled)
 
    Signals the amount of the local buffer \a filled as a number between 0 and 1.
*/
 
QT_END_NAMESPACE
 
#include "moc_qmediaplayer.cpp"