Qt 5.6 | Qt Multimedia | QML Video Shader Effects Example | main.cpp Example File

Qt 5.6.3 Reference Documentation

# main.cpp Example File

multimedia/video/qmlvideofx/main.cpp

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      ** Contact: http://www.qt.io/licensing/
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      ** This file is part of the Qt Mobility Components.
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      ** $QT_BEGIN_LICENSE:LGPL21$
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      #include <QtCore/QStandardPaths>
      #include <QtCore/QStringList>
      #include <QtQml/QQmlContext>
      #include <QtGui/QGuiApplication>
      #include <QtQuick/QQuickItem>
      #include <QtQuick/QQuickView>
      #include "filereader.h"
      #include "trace.h"

      #ifdef PERFORMANCEMONITOR_SUPPORT
      #include "performancemonitordeclarative.h"
      #endif

      int main(int argc, char *argv[])
      {
          QGuiApplication app(argc, argv);

      #ifdef PERFORMANCEMONITOR_SUPPORT
          PerformanceMonitor::qmlRegisterTypes();
      #endif

          QUrl fileName;
          qreal volume = 0.5;
          QStringList args = app.arguments();
      #ifdef PERFORMANCEMONITOR_SUPPORT
          PerformanceMonitor::State performanceMonitorState;
      #endif
          for (int i = 1; i < args.size(); ++i) {
              const QByteArray arg = args.at(i).toUtf8();
              if (arg.startsWith('-')) {
                  if ("-volume" == arg) {
                      if (i + 1 < args.size())
                          volume = 0.01 * args.at(++i).toInt();
                      else
                          qtTrace() << "Option \"-volume\" takes a value";
                  }
      #ifdef PERFORMANCEMONITOR_SUPPORT
                  else if (performanceMonitorState.parseArgument(arg)) {
                      // Do nothing
                  }
      #endif
                  else {
                      qtTrace() << "Option" << arg << "ignored";
                  }
              } else {
                  if (fileName.isEmpty())
                      fileName = QUrl::fromLocalFile(arg);
                  else
                      qtTrace() << "Argument" << arg << "ignored";
              }
          }

          QQuickView viewer;

          viewer.setSource(QUrl(QLatin1String("qrc:///qml/qmlvideofx/Main.qml")));
          QQuickItem *rootObject = viewer.rootObject();
          rootObject->setProperty("fileName", fileName);
          viewer.rootObject()->setProperty("volume", volume);

      #ifdef PERFORMANCEMONITOR_SUPPORT
          if (performanceMonitorState.valid) {
              rootObject->setProperty("perfMonitorsLogging", performanceMonitorState.logging);
              rootObject->setProperty("perfMonitorsVisible", performanceMonitorState.visible);
          }
          QObject::connect(&viewer, SIGNAL(afterRendering()),
                           rootObject, SLOT(qmlFramePainted()));
      #endif

          FileReader fileReader;
          viewer.rootContext()->setContextProperty("fileReader", &fileReader);

          const QUrl appPath(QUrl::fromLocalFile(app.applicationDirPath()));
          const QStringList picturesLocation = QStandardPaths::standardLocations(QStandardPaths::PicturesLocation);
          const QUrl imagePath = picturesLocation.isEmpty() ? appPath : QUrl::fromLocalFile(picturesLocation.first());
          viewer.rootContext()->setContextProperty("imagePath", imagePath);

          const QStringList moviesLocation = QStandardPaths::standardLocations(QStandardPaths::MoviesLocation);
          const QUrl videoPath = moviesLocation.isEmpty() ? appPath : QUrl::fromLocalFile(moviesLocation.first());
          viewer.rootContext()->setContextProperty("videoPath", videoPath);

          viewer.setTitle("qmlvideofx");
          viewer.setFlags(Qt::Window | Qt::WindowSystemMenuHint | Qt::WindowTitleHint |
                                Qt::WindowMinMaxButtonsHint | Qt::WindowCloseButtonHint);
          viewer.setMinimumSize(QSize(1280, 720));
          viewer.setResizeMode(QQuickView::SizeRootObjectToView);

          viewer.show();

          // Delay invocation of init until the event loop has started, to work around
          // a GL context issue on Harmattan: without this, we get the following error
          // when the first ShaderEffectItem is created:
          // "QGLShaderProgram::addShader: Program and shader are not associated with same context"
          QMetaObject::invokeMethod(viewer.rootObject(), "init", Qt::QueuedConnection);

          return app.exec();
      }