qmovie.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
// Qt-Security score:critical reason:data-parser
 
/*!
    \class QMovie
 
    \inmodule QtGui
 
    \brief The QMovie class is a convenience class for playing movies
    with QImageReader.
 
    This class is used to show simple animations without sound.
 
    First, create a QMovie object by passing either the name of a file or a
    pointer to a QIODevice containing an animated image format to QMovie's
    constructor. You can call isValid() to check if the image data is valid,
    before starting the movie. To start the movie, call start(). QMovie will
    enter \l Running state, and emit started() and stateChanged(). To get the
    current state of the movie, call state().
 
    To display the movie in your application, you can pass your QMovie object
    to QLabel::setMovie(). Example:
 
    \snippet code/src_gui_image_qmovie.cpp 0
 
    Whenever a new frame is available in the movie, QMovie will emit
    updated(). If the size of the frame changes, resized() is emitted. You can
    call currentImage() or currentPixmap() to get a copy of the current
    frame. When the movie is done, QMovie emits finished(). If any error
    occurs during playback (i.e, the image file is corrupt), QMovie will emit
    error().
 
    You can control the speed of the movie playback by calling setSpeed(),
    which takes the percentage of the original speed as an argument. Pause the
    movie by calling setPaused(true). QMovie will then enter \l Paused state
    and emit stateChanged(). If you call setPaused(false), QMovie will reenter
    \l Running state and start the movie again. To stop the movie, call
    stop().
 
    Certain animation formats allow you to set the background color. You can
    call setBackgroundColor() to set the color, or backgroundColor() to
    retrieve the current background color.
 
    currentFrameNumber() returns the sequence number of the current frame. The
    first frame in the animation has the sequence number 0. frameCount()
    returns the total number of frames in the animation, if the image format
    supports this. You can call loopCount() to get the number of times the
    movie should loop before finishing. nextFrameDelay() returns the number of
    milliseconds the current frame should be displayed.
 
    QMovie can be instructed to cache frames of an animation by calling
    setCacheMode().
 
    Call supportedFormats() for a list of formats that QMovie supports.
 
    \sa QLabel, QImageReader
*/
 
/*! \enum QMovie::MovieState
 
    This enum describes the different states of QMovie.
 
    \value NotRunning The movie is not running. This is QMovie's initial
    state, and the state it enters after stop() has been called or the movie
    is finished.
 
    \value Paused The movie is paused, and QMovie stops emitting updated() or
    resized(). This state is entered after calling pause() or
    setPaused(true). The current frame number it kept, and the movie will
    continue with the next frame when unpause() or setPaused(false) is called.
 
    \value Running The movie is running.
*/
 
/*! \enum QMovie::CacheMode
 
    This enum describes the different cache modes of QMovie.
 
    \value CacheNone No frames are cached (the default).
 
    \value CacheAll All frames are cached.
*/
 
/*! \fn void QMovie::started()
 
    This signal is emitted after QMovie::start() has been called, and QMovie
    has entered QMovie::Running state.
*/
 
/*! \fn void QMovie::resized(const QSize &size)
 
    This signal is emitted when the current frame has been resized to \a
    size. This effect is sometimes used in animations as an alternative to
    replacing the frame. You can call currentImage() or currentPixmap() to get a
    copy of the updated frame.
*/
 
/*! \fn void QMovie::updated(const QRect &rect)
 
    This signal is emitted when the rect \a rect in the current frame has been
    updated. You can call currentImage() or currentPixmap() to get a copy of the
    updated frame.
*/
 
/*! \fn void QMovie::frameChanged(int frameNumber)
 
    This signal is emitted when the frame number has changed to
    \a frameNumber.  You can call currentImage() or currentPixmap() to get a
    copy of the frame.
*/
 
/*!
    \fn void QMovie::stateChanged(QMovie::MovieState state)
 
    This signal is emitted every time the state of the movie changes. The new
    state is specified by \a state.
 
    \sa QMovie::state()
*/
 
/*! \fn void QMovie::error(QImageReader::ImageReaderError error)
 
    This signal is emitted by QMovie when the error \a error occurred during
    playback.  QMovie will stop the movie, and enter QMovie::NotRunning state.
 
    \sa lastError(), lastErrorString()
*/
 
/*! \fn void QMovie::finished()
 
    This signal is emitted when the movie has finished.
 
    \sa QMovie::stop()
*/
 
#include "qmovie.h"
 
#include "qglobal.h"
#include "qelapsedtimer.h"
#include "qimage.h"
#include "qimagereader.h"
#include "qpixmap.h"
#include "qrect.h"
#include "qelapsedtimer.h"
#include "qtimer.h"
#include "qlist.h"
#include "qbuffer.h"
#include "qdir.h"
#include "qloggingcategory.h"
#include "private/qimage_p.h"
#include "private/qobject_p.h"
#include "private/qproperty_p.h"
 
#include <map>
#include <memory>
 
#define QMOVIE_INVALID_DELAY -1
 
QT_BEGIN_NAMESPACE
 
class QFrameInfo
{
public:
    QPixmap pixmap;
    int delay;
    bool endMark;
    inline QFrameInfo(bool endMark)
        : pixmap(QPixmap()), delay(QMOVIE_INVALID_DELAY), endMark(endMark)
    { }
 
    inline QFrameInfo()
        : pixmap(QPixmap()), delay(QMOVIE_INVALID_DELAY), endMark(false)
    { }
 
    inline QFrameInfo(QPixmap &&pixmap, int delay)
        : pixmap(std::move(pixmap)), delay(delay), endMark(false)
    { }
 
    inline bool isValid()
    {
        return endMark || !(pixmap.isNull() && (delay == QMOVIE_INVALID_DELAY));
    }
 
    inline bool isEndMarker()
    { return endMark; }
 
    static inline QFrameInfo endMarker()
    { return QFrameInfo(true); }
};
Q_DECLARE_TYPEINFO(QFrameInfo, Q_RELOCATABLE_TYPE);
 
class QMoviePrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QMovie)
 
public:
    QMoviePrivate();
 
    void init(QMovie *qq, std::unique_ptr<QImageReader> r);
 
    bool isDone();
    bool next();
    int speedAdjustedDelay(int delay) const;
    bool isValid() const;
    bool jumpToFrame(int frameNumber);
    int frameCount() const;
    bool jumpToNextFrame();
    QFrameInfo infoForFrame(int frameNumber);
    void reset();
 
    inline void enterState(QMovie::MovieState newState) {
        movieState = newState;
        emit q_func()->stateChanged(newState);
    }
 
    // private slots
    void _q_loadNextFrame();
    void _q_loadNextFrame(bool starting);
 
    std::unique_ptr<QImageReader> reader = nullptr;
 
    void setSpeed(int percentSpeed) { q_func()->setSpeed(percentSpeed); }
    Q_OBJECT_COMPAT_PROPERTY_WITH_ARGS(QMoviePrivate, int, speed, &QMoviePrivate::setSpeed, 100)
 
    QMovie::MovieState movieState = QMovie::NotRunning;
    QRect frameRect;
    QPixmap currentPixmap;
    int currentFrameNumber = -1;
    int nextFrameNumber = 0;
    int greatestFrameNumber = -1;
    int nextDelay = 0;
    int playCounter = -1;
    qint64 initialDevicePos = 0;
    Q_OBJECT_BINDABLE_PROPERTY_WITH_ARGS(QMoviePrivate, QMovie::CacheMode, cacheMode,
                                         QMovie::CacheNone)
    bool haveReadAll = false;
    bool isFirstIteration = true;
    std::map<int, QFrameInfo> frameMap;
    QString absoluteFilePath;
 
    QTimer *nextImageTimer = nullptr;
};
 
/*! \internal
 */
QMoviePrivate::QMoviePrivate()
{
}
 
void QMoviePrivate::init(QMovie *qq, std::unique_ptr<QImageReader> r)
{
    q_ptr = qq;
    reader = std::move(r);
    nextImageTimer = new QTimer(qq);
    nextImageTimer->setSingleShot(true);
    QObject::connect(nextImageTimer, SIGNAL(timeout()),
                     qq, SLOT(_q_loadNextFrame()));
}
 
/*! \internal
 */
void QMoviePrivate::reset()
{
    nextImageTimer->stop();
    if (reader->device())
        initialDevicePos = reader->device()->pos();
    currentFrameNumber = -1;
    nextFrameNumber = 0;
    greatestFrameNumber = -1;
    nextDelay = 0;
    playCounter = -1;
    haveReadAll = false;
    isFirstIteration = true;
    frameMap.clear();
}
 
/*! \internal
 */
bool QMoviePrivate::isDone()
{
    return (playCounter == 0);
}
 
/*!
    \internal
 
    Given the original \a delay, this function returns the
    actual number of milliseconds to delay according to
    the current speed. E.g. if the speed is 200%, the
    result will be half of the original delay.
*/
int QMoviePrivate::speedAdjustedDelay(int delay) const
{
    return int( (qint64(delay) * qint64(100) ) / qint64(speed) );
}
 
/*!
    \internal
 
    Returns the QFrameInfo for the given \a frameNumber.
 
    If the frame number is invalid, an invalid QFrameInfo is
    returned.
 
    If the end of the animation has been reached, a
    special end marker QFrameInfo is returned.
 
*/
QFrameInfo QMoviePrivate::infoForFrame(int frameNumber)
{
    Q_Q(QMovie);
 
    if (frameNumber < 0)
        return QFrameInfo(); // Invalid
 
    if (haveReadAll && (frameNumber > greatestFrameNumber)) {
        if (frameNumber == greatestFrameNumber+1)
            return QFrameInfo::endMarker();
        return QFrameInfo(); // Invalid
    }
 
    // For an animated image format, the tradition is that QMovie calls read()
    // until canRead() == false, because the number of frames may not be known
    // in advance; but if we're abusing a multi-frame format as an animation,
    // canRead() may remain true, and we need to stop after reading the maximum
    // number of frames that the image provides.
    const bool supportsAnimation = reader->supportsOption(QImageIOHandler::Animation);
    const int stopAtFrame = supportsAnimation ? -1 : frameCount();
 
    // For an animated image format, QImageIOHandler::nextImageDelay() should
    // provide the time to wait until showing the next frame; but multi-frame
    // formats are not expected to provide this value, so use 1000 ms by default.
    const auto nextFrameDelay = [&]() { return supportsAnimation ? reader->nextImageDelay() : 1000; };
 
    if (cacheMode == QMovie::CacheNone) {
        if (frameNumber != currentFrameNumber+1) {
            // Non-sequential frame access
            if (!reader->jumpToImage(frameNumber)) {
                if (frameNumber == 0) {
                    // Special case: Attempt to "rewind" so we can loop
                    // ### This could be implemented as QImageReader::rewind()
                    if (reader->device()->isSequential())
                        return QFrameInfo(); // Invalid
                    QString fileName = reader->fileName();
                    QByteArray format = reader->format();
                    QIODevice *device = reader->device();
                    QColor bgColor = reader->backgroundColor();
                    QSize scaledSize = reader->scaledSize();
                    if (fileName.isEmpty())
                        reader = std::make_unique<QImageReader>(device, format);
                    else
                        reader = std::make_unique<QImageReader>(absoluteFilePath, format);
                    if (!reader->canRead()) // Provoke a device->open() call
                        emit q->error(reader->error());
                    reader->device()->seek(initialDevicePos);
                    reader->setBackgroundColor(bgColor);
                    reader->setScaledSize(scaledSize);
                } else {
                    return QFrameInfo(); // Invalid
                }
            }
        }
        qCDebug(lcImageIo, "CacheNone: read frame %d of %d", frameNumber, stopAtFrame);
        if (stopAtFrame > 0 ? (frameNumber < stopAtFrame) : reader->canRead()) {
            // reader says we can read. Attempt to actually read image
            // But if it's a non-animated multi-frame format and we know the frame count, stop there.
            if (stopAtFrame > 0)
                reader->jumpToImage(frameNumber);
            QImage anImage = reader->read();
            if (anImage.isNull()) {
                // Reading image failed.
                return QFrameInfo(); // Invalid
            }
            if (frameNumber > greatestFrameNumber)
                greatestFrameNumber = frameNumber;
            return QFrameInfo(QPixmap::fromImage(std::move(anImage)), nextFrameDelay());
        } else if (frameNumber != 0) {
            // We've read all frames now. Return an end marker
            haveReadAll = true;
            return QFrameInfo::endMarker();
        } else {
            // No readable frames
            haveReadAll = true;
            return QFrameInfo();
        }
    }
 
    // CacheMode == CacheAll
    if (frameNumber > greatestFrameNumber) {
        // Frame hasn't been read from file yet. Try to do it
        for (int i = greatestFrameNumber + 1; i <= frameNumber; ++i) {
            qCDebug(lcImageIo, "CacheAll: read frame %d of %d", frameNumber, stopAtFrame);
            if (stopAtFrame > 0 ? (frameNumber < stopAtFrame) : reader->canRead()) {
                // reader says we can read. Attempt to actually read image
                // But if it's a non-animated multi-frame format and we know the frame count, stop there.
                if (stopAtFrame > 0)
                    reader->jumpToImage(frameNumber);
                QImage anImage = reader->read();
                if (anImage.isNull()) {
                    // Reading image failed.
                    return QFrameInfo(); // Invalid
                }
                greatestFrameNumber = i;
                QFrameInfo info(QPixmap::fromImage(std::move(anImage)), nextFrameDelay());
                // Cache it!
                auto &e = frameMap[i] = std::move(info);
                if (i == frameNumber) {
                    return e;
                }
            } else {
                // We've read all frames now. Return an end marker
                haveReadAll = true;
                return frameNumber == greatestFrameNumber + 1 ? QFrameInfo::endMarker() : QFrameInfo();
            }
        }
    }
    // Return info for requested (cached) frame
    const auto it = frameMap.find(frameNumber);
    return it == frameMap.cend() ? QFrameInfo() : it->second;
}
 
/*!
    \internal
 
    Attempts to advance the animation to the next frame.
    If successful, currentFrameNumber, currentPixmap and
    nextDelay are updated accordingly, and true is returned.
    Otherwise, false is returned.
    When false is returned, isDone() can be called to
    determine whether the animation ended gracefully or
    an error occurred when reading the frame.
*/
bool QMoviePrivate::next()
{
    QElapsedTimer time;
    time.start();
    QFrameInfo info = infoForFrame(nextFrameNumber);
    if (!info.isValid())
        return false;
    if (info.isEndMarker()) {
        // We reached the end of the animation.
        if (isFirstIteration) {
            if (nextFrameNumber == 0) {
                // No frames could be read at all (error).
                return false;
            }
            // End of first iteration. Initialize play counter
            playCounter = reader->loopCount();
            isFirstIteration = false;
        }
        // Loop as appropriate
        if (playCounter != 0) {
            if (playCounter != -1) // Infinite?
                playCounter--;     // Nope
            nextFrameNumber = 0;
            return next();
        }
        // Loop no more. Done
        return false;
    }
    // Image and delay OK, update internal state
    currentFrameNumber = nextFrameNumber++;
    currentPixmap = info.pixmap;
 
    if (!speed)
        return true;
 
    nextDelay = speedAdjustedDelay(info.delay);
    // Adjust delay according to the time it took to read the frame
    int processingTime = time.elapsed();
    if (processingTime > nextDelay)
        nextDelay = 0;
    else
        nextDelay = nextDelay - processingTime;
    return true;
}
 
/*! \internal
 */
void QMoviePrivate::_q_loadNextFrame()
{
    _q_loadNextFrame(false);
}
 
void QMoviePrivate::_q_loadNextFrame(bool starting)
{
    Q_Q(QMovie);
    if (next()) {
        if (starting && movieState == QMovie::NotRunning) {
            enterState(QMovie::Running);
            emit q->started();
        }
 
        if (frameRect.size() != currentPixmap.rect().size()) {
            frameRect = currentPixmap.rect();
            emit q->resized(frameRect.size());
        }
 
        emit q->updated(frameRect);
        emit q->frameChanged(currentFrameNumber);
 
        if (speed && movieState == QMovie::Running)
            nextImageTimer->start(nextDelay);
    } else {
        // Could not read another frame
        if (!isDone()) {
            emit q->error(reader->error());
        }
 
        // A paused movie keeps its state so it can resume later.
        if (movieState == QMovie::Paused)
            return;
 
        nextFrameNumber = 0;
        isFirstIteration = true;
        playCounter = -1;
 
        // Only report a graceful finish when the movie was actually running;
        // a failed start() played nothing and must not emit finished().
        if (movieState == QMovie::Running) {
            enterState(QMovie::NotRunning);
            emit q->finished();
        }
    }
}
 
/*!
    \internal
*/
bool QMoviePrivate::isValid() const
{
    Q_Q(const QMovie);
 
    if (greatestFrameNumber >= 0)
        return true; // have we seen valid data
    bool canRead = reader->canRead();
    if (!canRead) {
        // let the consumer know it's broken
        //
        // ### the const_cast here is ugly, but 'const' of this method is
        // technically wrong right now, since it may cause the underlying device
        // to open.
        emit const_cast<QMovie*>(q)->error(reader->error());
    }
    return canRead;
}
 
/*!
    \internal
*/
bool QMoviePrivate::jumpToFrame(int frameNumber)
{
    if (frameNumber < 0)
        return false;
    if (currentFrameNumber == frameNumber)
        return true;
    nextFrameNumber = frameNumber;
    if (movieState == QMovie::Running)
        nextImageTimer->stop();
    _q_loadNextFrame();
    return (nextFrameNumber == currentFrameNumber+1);
}
 
/*!
    \internal
*/
int QMoviePrivate::frameCount() const
{
    int result;
    if ((result = reader->imageCount()) != 0)
        return result;
    if (haveReadAll)
        return greatestFrameNumber+1;
    return 0; // Don't know
}
 
/*!
    \internal
*/
bool QMoviePrivate::jumpToNextFrame()
{
    return jumpToFrame(currentFrameNumber+1);
}
 
/*!
    Constructs a QMovie object, passing the \a parent object to QObject's
    constructor.
 
    \sa setFileName(), setDevice(), setFormat()
 */
QMovie::QMovie(QObject *parent)
    : QObject(*new QMoviePrivate, parent)
{
    Q_D(QMovie);
    d->init(this, std::make_unique<QImageReader>());
}
 
/*!
    Constructs a QMovie object. QMovie will use read image data from \a
    device, which it assumes is open and readable. If \a format is not empty,
    QMovie will use the image format \a format for decoding the image
    data. Otherwise, QMovie will attempt to guess the format.
 
    The \a parent object is passed to QObject's constructor.
 */
QMovie::QMovie(QIODevice *device, const QByteArray &format, QObject *parent)
    : QObject(*new QMoviePrivate, parent)
{
    Q_D(QMovie);
    d->init(this, std::make_unique<QImageReader>(device, format));
    d->initialDevicePos = device->pos();
}
 
/*!
    Constructs a QMovie object. QMovie will use read image data from \a
    fileName. If \a format is not empty, QMovie will use the image format \a
    format for decoding the image data. Otherwise, QMovie will attempt to
    guess the format.
 
    The \a parent object is passed to QObject's constructor.
 */
QMovie::QMovie(const QString &fileName, const QByteArray &format, QObject *parent)
    : QObject(*new QMoviePrivate, parent)
{
    Q_D(QMovie);
    d->init(this, std::make_unique<QImageReader>(fileName, format));
    d->absoluteFilePath = QDir(fileName).absolutePath();
    if (d->reader->device())
        d->initialDevicePos = d->reader->device()->pos();
}
 
/*!
    Destructs the QMovie object.
*/
QMovie::~QMovie()
{
    Q_D(QMovie);
    d->reader.reset();
}
 
/*!
    Sets the current device to \a device. QMovie will read image data from
    this device when the movie is running.
 
    \sa device(), setFormat()
*/
void QMovie::setDevice(QIODevice *device)
{
    Q_D(QMovie);
    d->reader->setDevice(device);
    d->reset();
}
 
/*!
    Returns the device QMovie reads image data from. If no device has
    currently been assigned, \nullptr is returned.
 
    \sa setDevice(), fileName()
*/
QIODevice *QMovie::device() const
{
    Q_D(const QMovie);
    return d->reader->device();
}
 
/*!
    Sets the name of the file that QMovie reads image data from, to \a
    fileName.
 
    \sa fileName(), setDevice(), setFormat()
*/
void QMovie::setFileName(const QString &fileName)
{
    Q_D(QMovie);
    d->absoluteFilePath = QDir(fileName).absolutePath();
    d->reader->setFileName(fileName);
    d->reset();
}
 
/*!
    Returns the name of the file that QMovie reads image data from. If no file
    name has been assigned, or if the assigned device is not a file, an empty
    QString is returned.
 
    \sa setFileName(), device()
*/
QString QMovie::fileName() const
{
    Q_D(const QMovie);
    return d->reader->fileName();
}
 
/*!
    Sets the format that QMovie will use when decoding image data, to \a
    format. By default, QMovie will attempt to guess the format of the image
    data.
 
    You can call supportedFormats() for the full list of formats
    QMovie supports.
 
    \sa QImageReader::supportedImageFormats()
*/
void QMovie::setFormat(const QByteArray &format)
{
    Q_D(QMovie);
    d->reader->setFormat(format);
}
 
/*!
    Returns the format that QMovie uses when decoding image data. If no format
    has been assigned, an empty QByteArray() is returned.
 
    \sa setFormat()
*/
QByteArray QMovie::format() const
{
    Q_D(const QMovie);
    return d->reader->format();
}
 
/*!
    For image formats that support it, this function sets the background color
    to \a color.
 
    \sa backgroundColor()
*/
void QMovie::setBackgroundColor(const QColor &color)
{
    Q_D(QMovie);
    d->reader->setBackgroundColor(color);
}
 
/*!
    Returns the background color of the movie. If no background color has been
    assigned, an invalid QColor is returned.
 
    \sa setBackgroundColor()
*/
QColor QMovie::backgroundColor() const
{
    Q_D(const QMovie);
    return d->reader->backgroundColor();
}
 
/*!
    Returns the current state of QMovie.
 
    \sa MovieState, stateChanged()
*/
QMovie::MovieState QMovie::state() const
{
    Q_D(const QMovie);
    return d->movieState;
}
 
/*!
    Returns the rect of the last frame. If no frame has yet been updated, an
    invalid QRect is returned.
 
    \sa currentImage(), currentPixmap()
*/
QRect QMovie::frameRect() const
{
    Q_D(const QMovie);
    return d->frameRect;
}
 
/*!
    Returns the current frame as a QPixmap.
 
    \sa currentImage(), updated()
*/
QPixmap QMovie::currentPixmap() const
{
    Q_D(const QMovie);
    return d->currentPixmap;
}
 
/*!
    Returns the current frame as a QImage.
 
    \sa currentPixmap(), updated()
*/
QImage QMovie::currentImage() const
{
    Q_D(const QMovie);
    return d->currentPixmap.toImage();
}
 
/*!
    Returns \c true if the movie is valid (e.g., the image data is readable and
    the image format is supported); otherwise returns \c false.
 
    For information about why the movie is not valid, see lastError().
*/
bool QMovie::isValid() const
{
    Q_D(const QMovie);
    return d->isValid();
}
 
/*!
    Returns the most recent error that occurred while attempting to read image data.
 
    \sa lastErrorString()
*/
QImageReader::ImageReaderError QMovie::lastError() const
{
    Q_D(const QMovie);
    return d->reader->error();
}
 
/*!
     Returns a human-readable representation of the most recent error that occurred
     while attempting to read image data.
 
    \sa lastError()
*/
QString QMovie::lastErrorString() const
{
    Q_D(const QMovie);
    return d->reader->errorString();
}
 
/*!
    Returns the number of frames in the movie.
 
    Certain animation formats do not support this feature, in which
    case 0 is returned.
*/
int QMovie::frameCount() const
{
    Q_D(const QMovie);
    return d->frameCount();
}
 
/*!
    Returns the number of milliseconds QMovie will wait before updating the
    next frame in the animation.
*/
int QMovie::nextFrameDelay() const
{
    Q_D(const QMovie);
    return d->nextDelay;
}
 
/*!
    Returns the sequence number of the current frame. The number of the first
    frame in the movie is 0.
*/
int QMovie::currentFrameNumber() const
{
    Q_D(const QMovie);
    return d->currentFrameNumber;
}
 
/*!
    Jumps to the next frame. Returns \c true on success; otherwise returns \c false.
*/
bool QMovie::jumpToNextFrame()
{
    Q_D(QMovie);
    return d->jumpToNextFrame();
}
 
/*!
    Jumps to frame number \a frameNumber. Returns \c true on success; otherwise
    returns \c false.
*/
bool QMovie::jumpToFrame(int frameNumber)
{
    Q_D(QMovie);
    return d->jumpToFrame(frameNumber);
}
 
/*!
    Returns the number of times the movie will loop before it finishes.
    If the movie will only play once (no looping), loopCount returns 0.
    If the movie loops forever, loopCount returns -1.
 
    Note that, if the image data comes from a sequential device (e.g. a
    socket), QMovie can only loop the movie if the cacheMode is set to
    QMovie::CacheAll.
*/
int QMovie::loopCount() const
{
    Q_D(const QMovie);
    return d->reader->loopCount();
}
 
/*!
    If \a paused is true, QMovie will enter \l Paused state and emit
    stateChanged(Paused); otherwise it will enter \l Running state and emit
    stateChanged(Running).
 
    \sa state()
*/
void QMovie::setPaused(bool paused)
{
    Q_D(QMovie);
    if (paused) {
        if (d->movieState == NotRunning)
            return;
        d->enterState(Paused);
        d->nextImageTimer->stop();
    } else {
        if (d->movieState == Running)
            return;
        d->enterState(Running);
        d->nextImageTimer->start(nextFrameDelay());
    }
}
 
/*!
    \property QMovie::speed
    \brief the movie's speed
 
    The speed is measured in percentage of the original movie speed.
    The default speed is 100%.
    Example:
 
    \snippet code/src_gui_image_qmovie.cpp 1
*/
void QMovie::setSpeed(int percentSpeed)
{
    Q_D(QMovie);
    if (!d->speed && d->movieState == Running)
        d->nextImageTimer->start(nextFrameDelay());
    if (percentSpeed != d->speed) {
        d->speed = percentSpeed;
        d->speed.notify();
    } else {
        d->speed.removeBindingUnlessInWrapper();
    }
}
 
int QMovie::speed() const
{
    Q_D(const QMovie);
    return d->speed;
}
 
QBindable<int> QMovie::bindableSpeed()
{
    Q_D(QMovie);
    return &d->speed;
}
 
/*!
    Starts the movie. QMovie will enter \l Running state, and start emitting
    updated() and resized() as the movie progresses.
 
    If QMovie is in the \l Paused state, this function is equivalent
    to calling setPaused(false). If QMovie is already in the \l
    Running state, this function does nothing.
 
    \sa stop(), setPaused()
*/
void QMovie::start()
{
    Q_D(QMovie);
    if (d->movieState == NotRunning) {
        d->_q_loadNextFrame(true);
    } else if (d->movieState == Paused) {
        setPaused(false);
    }
}
 
/*!
    Stops the movie. QMovie enters \l NotRunning state, and stops emitting
    updated() and resized(). If start() is called again, the movie will
    restart from the beginning.
 
    If QMovie is already in the \l NotRunning state, this function
    does nothing.
 
    \sa start(), setPaused()
*/
void QMovie::stop()
{
    Q_D(QMovie);
    if (d->movieState == NotRunning)
        return;
    d->enterState(NotRunning);
    d->nextImageTimer->stop();
    d->nextFrameNumber = 0;
}
 
/*!
    Returns the scaled size of frames.
 
    \sa QImageReader::scaledSize()
*/
QSize QMovie::scaledSize()
{
    Q_D(QMovie);
    return d->reader->scaledSize();
}
 
/*!
    Sets the scaled frame size to \a size.
 
    \sa QImageReader::setScaledSize()
*/
void QMovie::setScaledSize(const QSize &size)
{
    Q_D(QMovie);
    d->reader->setScaledSize(size);
}
 
/*!
    Returns the list of image formats supported by QMovie.
 
    \sa QImageReader::supportedImageFormats()
*/
QList<QByteArray> QMovie::supportedFormats()
{
    QList<QByteArray> list = QImageReader::supportedImageFormats();
 
    QBuffer buffer;
    buffer.open(QIODevice::ReadOnly);
 
    const auto doesntSupportAnimation =
            [&buffer](const QByteArray &format) {
                return !QImageReader(&buffer, format).supportsOption(QImageIOHandler::Animation);
            };
 
    list.removeIf(doesntSupportAnimation);
    return list;
}
 
/*!
    \property QMovie::cacheMode
    \brief the movie's cache mode
 
    Caching frames can be useful when the underlying animation format handler
    that QMovie relies on to decode the animation data does not support
    jumping to particular frames in the animation, or even "rewinding" the
    animation to the beginning (for looping). Furthermore, if the image data
    comes from a sequential device, it is not possible for the underlying
    animation handler to seek back to frames whose data has already been read
    (making looping altogether impossible).
 
    To aid in such situations, a QMovie object can be instructed to cache the
    frames, at the added memory cost of keeping the frames in memory for the
    lifetime of the object.
 
    By default, this property is set to \l CacheNone.
 
    \sa QMovie::CacheMode
*/
 
QMovie::CacheMode QMovie::cacheMode() const
{
    Q_D(const QMovie);
    return d->cacheMode;
}
 
void QMovie::setCacheMode(CacheMode cacheMode)
{
    Q_D(QMovie);
    d->cacheMode = cacheMode;
}
 
QBindable<QMovie::CacheMode> QMovie::bindableCacheMode()
{
    Q_D(QMovie);
    return &d->cacheMode;
}
 
QT_END_NAMESPACE
 
#include "moc_qmovie.cpp"