#include "opencv2/video/video.hpp"

#include "opencv2/highgui/highgui.hpp"

#include <opencv2/imgproc/imgproc.hpp>

#include <stdio.h>

#include <iostream>

using namespace cv;

using namespace std;

int main(int argc, char* argv[])

{   /* Main function: */

    CvCapture* pCap = NULL;

    char* avi_name = argv[1];

    printf("Video name = %s\n", avi_name);

    /* Create source video: */

    if(avi_name)

        pCap = cvCaptureFromFile(avi_name);

    if(pCap==NULL)

    {

        printf("\nCan't open %s file\n",avi_name);

        return -1;

    }

    cvNamedWindow("gray");

    CvVideoWriter* pFGAvi = NULL;

    while(pCap)

    {   /* Main loop: */

        IplImage*   pImg  = NULL;

        pImg = cvQueryFrame(pCap);

        if(pImg == NULL) break;

        if (pFGAvi == NULL)

           pFGAvi=cvCreateVideoWriter(

            argv[2],

            CV_FOURCC_DEFAULT,

            25,

            cvSize(pImg->width, pImg->height),1);

        IplImage* gray = cvCreateImage(cvSize(pImg->width, pImg->height),pImg->depth,1);

        cvCvtColor(pImg, gray, CV_BGR2GRAY);

        IplImage* gray3 = cvCreateImage(cvSize(pImg->width, pImg->height),pImg->depth,3);

        cvCvtColor(gray, gray3, CV_GRAY2BGR);

        cvWriteFrame(pFGAvi, gray3);

        cvShowImage("gray", gray);

        cvWaitKey(1);

        if (gray)

            cvReleaseImage(&gray);

        if (gray3)

            cvReleaseImage(&gray3);

    }

    if (pFGAvi)

        cvReleaseVideoWriter(&pFGAvi);

    if(pCap)

        cvReleaseCapture(&pCap);

    pCap = cvCaptureFromFile(argv[2]);

    if(pCap==NULL)

    {

        printf("\nCan't open %s file\n",avi_name);

        return -1;

    }

    while(pCap)

    {   /* Main loop: */

        IplImage*   pImg  = NULL;

        pImg = cvQueryFrame(pCap);

        if(pImg == NULL) break;

        cvShowImage("gray", pImg);

        cvWaitKey(1);

    }

    if(pCap)

        cvReleaseCapture(&pCap);

    return 0;

}   /* main() */