Timeout when get image data from clipboard

// a.cpp
#include <QGuiApplication>
#include <QImage>
#include <QClipboard>
int main(int argc, char *argv[])

{ 
    QGuiApplication a(argc, argv);
    // If you load a more complex image, the size of the image pair can be reduced a lot. I tried using a jpg image with a size of 5613x3744, and I can get the same result.
    QImage image(20000, 20000, QImage::Format_ARGB32);
    image.fill(Qt::red);
    a.clipboard()->setImage(image);
    return a.exec();
 }

// b.cpp
#include <QGuiApplication> 
#include <QImage> 
#include <QClipboard>
#include <QMimeData>
#include <QtDebug>
#include <QElapsedTimer>
int main(int argc, char *argv[])
{
    QGuiApplication a(argc, argv);
    QClipboard *b = a.clipboard();
    QObject::connect(b, &QClipboard::dataChanged, [b] { 
        QElapsedTimer et; 
        et.start();
        const QMimeData *data = b->mimeData();
        if (data->hasFormat("image/png")) { 
             qint64 start = et.elapsed();
             qDebug() << data->data("image/png").length();
             qDebug() << et.elapsed() - start;
       }

   });
   return a.exec();
}

0
5012