Capture system camera frames from thread

FalsinSoft

Hi all

I need to capture frames from a system camera using a separate thread. Follow my code from a derived QThread class:

void CameraMonitor::run()
{
	QScopedPointer<QCamera> camera(new QCamera(cameraDevice));
    QScopedPointer<QMediaCaptureSession> captureSession(new QMediaCaptureSession());
    QScopedPointer<QVideoSink> videoSink(new QVideoSink());

    camera->setFocusMode(QCamera::FocusModeAuto);

    connect(videoSink.data(), &QVideoSink::videoFrameChanged, this, &CameraMonitor::processVideoFrame);
    captureSession->setVideoSink(videoSink.data());
    captureSession->setCamera(camera.data());
    camera->start();

    exec();

    camera->stop();
    captureSession->setCamera(nullptr);
    captureSession->setVideoSink(nullptr);
}

void CameraMonitor::processVideoFrame(const QVideoFrame &videoFrame)
{
    //....
}

My problem is that the processVideoFrame slot is nevel called and I don't understand if I made some mystake in the code or simply this is not the correct way to get the result. I can see the camera led on that's mean the code activate the camera but I don't understand if it doesn't acquire or the signal/slot sistem doesn't work also calling exec() inside the thread.
Someone can help me?
Thank you

Ronel_qtmaster

@FalsinSoft first of all
void QCamera::setViewfinder(QAbstractVideoSurface *surface)

You have to create an abstract video surface and add it to the camera using the function setViewfinder.

Then, the video surface will notify you when a frame is present
Finally, call your thread class when the frame is present and give it as an argument the image(QVideoFrame converted to QImage)

FalsinSoft

@Ronel_qtmaster Thank you for your reply but I'm developing using Qt6 and there is no method setViewfinder in the "new" QCamera class...

Ronel_qtmaster

This post is deleted!

Ronel_qtmaster

@FalsinSoft SORRY I AM not using qt6