videoplayer.cpp Example File | Qt Multimedia 5.9

Qt 5.9 | Qt Multimedia | Video Graphics Item Example | videoplayer.cpp Example File

Qt 5.9.4 Reference Documentation

# videoplayer.cpp Example File

multimediawidgets/videographicsitem/videoplayer.cpp

      /****************************************************************************
      **
      ** Copyright (C) 2017 The Qt Company Ltd.
      ** Contact: https://www.qt.io/licensing/
      **
      ** This file is part of the examples of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:BSD$
      ** Commercial License Usage
      ** Licensees holding valid commercial Qt licenses may use this file in
      ** accordance with the commercial license agreement provided with the
      ** Software or, alternatively, in accordance with the terms contained in
      ** a written agreement between you and The Qt Company. For licensing terms
      ** and conditions see https://www.qt.io/terms-conditions. For further
      ** information use the contact form at https://www.qt.io/contact-us.
      **
      ** BSD License Usage
      ** Alternatively, you may use this file under the terms of the BSD license
      ** as follows:
      **
      ** "Redistribution and use in source and binary forms, with or without
      ** modification, are permitted provided that the following conditions are
      ** met:
      **   * Redistributions of source code must retain the above copyright
      **     notice, this list of conditions and the following disclaimer.
      **   * Redistributions in binary form must reproduce the above copyright
      **     notice, this list of conditions and the following disclaimer in
      **     the documentation and/or other materials provided with the
      **     distribution.
      **   * Neither the name of The Qt Company Ltd nor the names of its
      **     contributors may be used to endorse or promote products derived
      **     from this software without specific prior written permission.
      **
      **
      ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
      ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
      ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
      ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
      ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
      ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
      ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
      ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
      **
      ** $QT_END_LICENSE$
      **
      ****************************************************************************/

      #include "videoplayer.h"

      #include <QtWidgets>
      #include <QVideoSurfaceFormat>
      #include <QGraphicsVideoItem>

      VideoPlayer::VideoPlayer(QWidget *parent)
          : QWidget(parent)
          , mediaPlayer(0, QMediaPlayer::VideoSurface)
          , videoItem(0)
          , playButton(0)
          , positionSlider(0)
      {
          const QRect screenGeometry = QApplication::desktop()->screenGeometry(this);
          videoItem = new QGraphicsVideoItem;
          videoItem->setSize(QSizeF(screenGeometry.width() / 3, screenGeometry.height() / 2));

          QGraphicsScene *scene = new QGraphicsScene(this);
          QGraphicsView *graphicsView = new QGraphicsView(scene);

          scene->addItem(videoItem);

          QSlider *rotateSlider = new QSlider(Qt::Horizontal);
          rotateSlider->setToolTip(tr("Rotate Video"));
          rotateSlider->setRange(-180,  180);
          rotateSlider->setValue(0);

          connect(rotateSlider, &QAbstractSlider::valueChanged,
                  this, &VideoPlayer::rotateVideo);

          QAbstractButton *openButton = new QPushButton(tr("Open..."));
          connect(openButton, &QAbstractButton::clicked, this, &VideoPlayer::openFile);

          playButton = new QPushButton;
          playButton->setEnabled(false);
          playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));

          connect(playButton, &QAbstractButton::clicked, this, &VideoPlayer::play);

          positionSlider = new QSlider(Qt::Horizontal);
          positionSlider->setRange(0, 0);

          connect(positionSlider, &QAbstractSlider::sliderMoved,
                  this, &VideoPlayer::setPosition);

          QBoxLayout *controlLayout = new QHBoxLayout;
          controlLayout->setMargin(0);
          controlLayout->addWidget(openButton);
          controlLayout->addWidget(playButton);
          controlLayout->addWidget(positionSlider);

          QBoxLayout *layout = new QVBoxLayout(this);
          layout->addWidget(graphicsView);
          layout->addWidget(rotateSlider);
          layout->addLayout(controlLayout);

          mediaPlayer.setVideoOutput(videoItem);
          connect(&mediaPlayer, &QMediaPlayer::stateChanged,
                  this, &VideoPlayer::mediaStateChanged);
          connect(&mediaPlayer, &QMediaPlayer::positionChanged, this, &VideoPlayer::positionChanged);
          connect(&mediaPlayer, &QMediaPlayer::durationChanged, this, &VideoPlayer::durationChanged);
      }

      VideoPlayer::~VideoPlayer()
      {
      }

      QSize VideoPlayer::sizeHint() const
      {
          return (videoItem->size() * qreal(3) / qreal(2)).toSize();
      }

      bool VideoPlayer::isPlayerAvailable() const
      {
          return mediaPlayer.isAvailable();
      }

      void VideoPlayer::openFile()
      {
          QFileDialog fileDialog(this);
          fileDialog.setAcceptMode(QFileDialog::AcceptOpen);
          fileDialog.setWindowTitle(tr("Open Movie"));
          const QStringList supportedMimeTypes = mediaPlayer.supportedMimeTypes();
          if (!supportedMimeTypes.isEmpty())
              fileDialog.setMimeTypeFilters(supportedMimeTypes);
          fileDialog.setDirectory(QStandardPaths::standardLocations(QStandardPaths::MoviesLocation).value(0, QDir::homePath()));
          if (fileDialog.exec() == QDialog::Accepted)
              load(fileDialog.selectedUrls().constFirst());
      }

      void VideoPlayer::load(const QUrl &url)
      {
          mediaPlayer.setMedia(url);
          playButton->setEnabled(true);
      }

      void VideoPlayer::play()
      {
          switch(mediaPlayer.state()) {
          case QMediaPlayer::PlayingState:
              mediaPlayer.pause();
              break;
          default:
              mediaPlayer.play();
              break;
          }
      }

      void VideoPlayer::mediaStateChanged(QMediaPlayer::State state)
      {
          switch(state) {
          case QMediaPlayer::PlayingState:
              playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPause));
              break;
          default:
              playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
              break;
          }
      }

      void VideoPlayer::positionChanged(qint64 position)
      {
          positionSlider->setValue(position);
      }

      void VideoPlayer::durationChanged(qint64 duration)
      {
          positionSlider->setRange(0, duration);
      }

      void VideoPlayer::setPosition(int position)
      {
          mediaPlayer.setPosition(position);
      }

      void VideoPlayer::rotateVideo(int angle)
      {
          //rotate around the center of video element
          qreal x = videoItem->boundingRect().width() / 2.0;
          qreal y = videoItem->boundingRect().height() / 2.0;
          videoItem->setTransform(QTransform().translate(x, y).rotate(angle).translate(-x, -y));
      }