QT6 Using QVideoSink with QCamera to process every frame

[svar]

I`m digging example qt6 6.2.2 camera.pro and found next line code:

m_captureSession.setVideoOutput(ui->viewfinder);

this is the way of outing frames to ui.

I know what QVideoSinc is used for grab every frame and process it.

I have replaced this line with

m_captureSession.setVideoSink(&videoSink);

where videoSinc defined as my class :

class MyVideoSinc : public QVideoSink
{
    Q_OBJECT
public:
    bool videoframeReady=false;
    MyVideoSinc()
    {
        connect(this, &QVideoSink::videoFrameChanged, this, &MyVideoSinc::hvideoFrameChanged);
    }
public Q_SLOTS:

    void hvideoFrameChanged(const QVideoFrame &frame)
    {
        videoframeReady=true;
    }
};

hvideoFrameChanged raised for every frame in Windows build, but only once in Android application.

What is wrong here. How to grab and process frames from QCamera in QT6 ? I don`t want show frames with ui->viewfinder. I need processing frames myself.