#include <QtWidgets>
#include <Windows.h>

Q_GUI_EXPORT QImage qt_imageFromWinHBITMAP(HDC hdc, HBITMAP bitmap, int w, int h);
Q_GUI_EXPORT QPixmap qt_pixmapFromWinHBITMAP(HBITMAP bitmap, int hbitmapFormat = 0);

int main(int argc, char **argv)
{
    QApplication a(argc, argv);
    QWidget w;
    w.show();
    HDC display_dc = GetDC(0);
    HDC bitmap_dc = CreateCompatibleDC(display_dc);
    HBITMAP bitmap = (HBITMAP)LoadImage(NULL, L"test.bmp", IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);
    SelectObject(bitmap_dc, bitmap);
   {
        QImage image = qt_imageFromWinHBITMAP(display_dc, bitmap, 297, 475);
        image.save("test.png", "PNG");
        QPixmap pix = qt_pixmapFromWinHBITMAP(bitmap);
        pix.save("testPix.png", "PNG");
    }

    DeleteObject(SelectObject(bitmap_dc, bitmap));
#ifndef Q_OS_WINCE
    DeleteDC(bitmap_dc);
#endif
    ReleaseDC(0, display_dc);
    return a.exec();
}