currently I want to show 4 videos on 4 different Displays. The videos should be synchronized. Therefore I created a QVideoWidget for every Display stored in

      QList<QVideoWidget*> vws = {}; 

Then I created the QVector with the QAbstractVideoSurfaces

QVector<QAbstractVideoSurface*> *surfaces = new QVector<QAbstractVideoSurface*>;

        for(int i = 0; i < qApp->screens().count(); i++){
            if( i != displayToUse_NotBlocking){
                VideoSurface *vs = new VideoSurface(vws.at(i)->videoSurface());

                QVideoSurfaceFormat format(qApp->screens().at(i)->geometry().size(), QVideoFrame::Format_RGB32);

                vws.at(i)->show();
                vws.at(i)->showFullScreen();
        
                vs->start(format);
                surfaces->append(vs);

                qDebug()<< vs->surfaceFormat();
            }
        }

Here VideoSurface is the class implementing the QAbstractVideoSurface

#ifndef VIDEOSURFACE_H
#define VIDEOSURFACE_H

#include <QtMultimedia>
#include <QAbstractVideoSurface>
#include <QVideoFrame>
#include <QAbstractVideoBuffer>
#include <QLabel>
#include <QApplication>
class VideoSurface : public QAbstractVideoSurface
{
public:

    VideoSurface(QObject *parent = nullptr): QAbstractVideoSurface(parent) {};

    QList<QVideoFrame::PixelFormat> supportedPixelFormats(
            QAbstractVideoBuffer::HandleType handleType) const
    {
        if (handleType == QAbstractVideoBuffer::NoHandle) {
            QList<QVideoFrame::PixelFormat> *list = new QList<QVideoFrame::PixelFormat>;
            list->append(QVideoFrame::Format_YUV420P);
            list->append(QVideoFrame::Format_RGB24);
            list->append(QVideoFrame::Format_BGR32);
            list->append(QVideoFrame::Format_BGR24);
            list->append(QVideoFrame::Format_RGB32);

            return *list;
        } else {
            return QList<QVideoFrame::PixelFormat>();
        }
    }

    // nothing is done with the image in here
    bool present(const QVideoFrame &frame)
    {
        qDebug() << frame.pixelFormat();



        return true;
        }

};





#endif // VIDEOSURFACE_H

Then I added the output to a previously created QMediaPlayer and started the video.

globalplayer->setVideoOutput(*surfaces);
        globalplayer->setMedia(QUrl::fromLocalFile("MyPath"));

        qDebug() << "isVideoAvailable: " << globalplayer->isVideoAvailable();
        qDebug() << ": " << globalplayer->mediaStatus();
        globalplayer->play();

Now I only see a black screen. But a frame is obviously grabbed in the present() function. (qDebug Output here: Format_RGB32)

Has anyone an idea what I#M doing wrong ? Do i have to process the frame ? If only use globalplayer->setVideoOutput(QVideoWidget) everything works fine.

Kind regards,

Kobe

PS: If there is a way to show 4 different videos in sync, pls let me know