multiple exposure video sequence

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Hi, everyone, I want to know is it possible to get image sequence like this?

Frame0 (exposure A) -> Frame1 (exposure B) -> Frame2 (exposure A) -> Frame3 (exposure B)

As following was the way I tried, I expected that the “exposure 0” window showing the loner exposure image, and “exposure 1” showing the shorter one, but the result was both windows blink at the same time.

VideoCapture vc(0);

Mat src;

while( true )
{
    vc.set(CV_CAP_PROP_EXPOSURE, 0);
    vc >> src;
    imshow("exposure 0", src);

    vc.set(CV_CAP_PROP_EXPOSURE, -2);
    vc >> src;
    imshow("exposure 1", src);

    waitKey(1);
}

I guess there are some sync problem, because longer exposure makes longer response time, is there any solution?