以下是將兩個視訊同時顯示在一個框內：

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <cv.h>
#include <highgui.h>
 


void Show_two_videos()
{
IplImage *newFrame = NULL;
IplImage *frame1 = NULL;
IplImage *frame2 = NULL;
CvCapture * pCapture1 = cvCaptureFromAVI("第一個視訊地址");
CvCapture * pCapture2 = cvCaptureFromAVI("第二個視訊地址");
CvRect rect;
CvVideoWriter *pWriter = NULL;
//get the frame number of two videos  
int frameNo1 = (int)cvGetCaptureProperty(pCapture1, CV_CAP_PROP_FRAME_COUNT);
int frameNo2 = (int)cvGetCaptureProperty(pCapture2, CV_CAP_PROP_FRAME_COUNT);
if (frameNo1 != frameNo2)
printf("video length 1 != video length 2\n");
else
printf("Total frame numbers: %d\n", frameNo1);
//get the frame width of two videos  
int frameWidth1 = (int)cvGetCaptureProperty(pCapture1, CV_CAP_PROP_FRAME_WIDTH);
int frameWidth2 = (int)cvGetCaptureProperty(pCapture2, CV_CAP_PROP_FRAME_WIDTH);
if (frameWidth1 != frameWidth2)
printf("video width 1 != video width 2\n");
else
printf("frame width: %d\n", frameWidth1);
//get the frame height of two videos  
int frameHeight1 = (int)cvGetCaptureProperty(pCapture1, CV_CAP_PROP_FRAME_HEIGHT);
int frameHeight2 = (int)cvGetCaptureProperty(pCapture2, CV_CAP_PROP_FRAME_HEIGHT);
if (frameHeight1 != frameHeight2)
printf("video height 1 != video height 2\n");
else
printf("frame height: %d\n", frameHeight1);
//get the video fps  
int fps1 = (int)cvGetCaptureProperty(pCapture1, CV_CAP_PROP_FPS);
int fps2 = (int)cvGetCaptureProperty(pCapture2, CV_CAP_PROP_FPS);
if (fps1 != fps2)
printf("video fps 1 != video fps 2\n");
else
printf("frame fps: %d\n", fps1);


int initFlag = 0;
int counter = 0;
while ((frame1 = cvQueryFrame(pCapture1)) != NULL && (frame2 = cvQueryFrame(pCapture2)) != NULL)
{
printf("%d\n", counter++);
if (initFlag == 0)
{
newFrame = cvCreateImage(cvSize(frame1->width * 2, frame1->height), frame1->depth, frame1->nChannels);
pWriter = cvCreateVideoWriter("合成後視訊的地址", CV_FOURCC('X', 'V', 'I', 'D'), fps1, cvSize(frame1->width * 2, frame1->height), 1);
initFlag = 1;
}
rect.x = 0;
rect.y = 0;
rect.height = frameHeight1;
rect.width = frameWidth1;
//use ROI to implement the video split joint  
cvSetImageROI(newFrame, rect);
cvCopyImage(frame1, newFrame);
cvResetImageROI(newFrame);
rect.x = frameWidth1;
rect.y = 0;
rect.height = frameHeight1;
rect.width = frameWidth1;
cvSetImageROI(newFrame, rect);
cvCopyImage(frame2, newFrame);
cvResetImageROI(newFrame);
cvWriteFrame(pWriter, newFrame);
}
cvReleaseImage(&frame1);
cvReleaseImage(&frame2);
cvReleaseImage(&newFrame);
cvReleaseVideoWriter(&pWriter);
}


int main(int argc, char *argv[])
{
Show_two_videos();    //同時顯示兩個視訊
return 0;
}