#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
#include <fstream>
int g_slider_position = 0;
CvCapture* g_capture = NULL;
void onTrackbarSlide(int pos)
{
    cvSetCaptureProperty(
        g_capture,
        CV_CAP_PROP_POS_FRAMES,
        pos
    );
}
int main( int argc, char** argv )
{
    cvNamedWindow( "Example3", CV_WINDOW_AUTOSIZE );
    g_capture = cvCreateFileCapture( "ab.MP4" );
    int frames = (int) cvGetCaptureProperty(
                     g_capture,
                     CV_CAP_PROP_FRAME_COUNT
                 );
    if( frames!= 0 )
    {
        cvCreateTrackbar(
            "Position",
            "Example3",
            &g_slider_position,
            frames,
            onTrackbarSlide
        );
    }
    IplImage* frame;
// While loop (as in Example 2) capture & show video
while(1)
    {
        frame = cvQueryFrame( g_capture );
        if( !frame ) break;
        cvShowImage( "Example2", frame );
        char c = cvWaitKey(33);
        if( c == 27 ) break;
    }
// Release memory and destroy window
cvDestroyWindow( "Example3" );
    return(0);
}