int main(int argc, char * argv[])
{
    CvCapture* pCapture = cvCreateCameraCapture(0);
    IplImage * pFrame;
    IplImage *psrc;
    IplImage *src = cvCreateImage(cvSize(700,700), IPL_DEPTH_8U,3);
    IplImage *gsrc = cvCreateImage(cvGetSize(src), IPL_DEPTH_8U,1);
     
    IplImage *dsw ;
    IplImage *dst;
    CvMemStorage *storage;
    CvSeq *first_contour;
     
    while(1)
    {
        psrc=cvQueryFrame(pCapture ); 
         
        cvResize(psrc,src,1);
        cvCvtColor(src,gsrc,CV_BGR2GRAY);
 
        dsw = cvCreateImage(cvGetSize(src), 8, 1);  
        dst = cvCreateImage(cvGetSize(src), 8, 3);
 
        storage = cvCreateMemStorage(0);  
        first_contour = NULL;  
 
        //turn the src image to a binary image  
        //cvThreshold(src, dsw, 125, 255, CV_THRESH_BINARY_INV);  
        cvThreshold(gsrc, dsw, 100, 255, CV_THRESH_BINARY);  
 
        cvFindContours(dsw, storage, &first_contour, sizeof(CvContour), CV_RETR_LIST, CV_CHAIN_APPROX_SIMPLE);  
        cvZero(dst);  
        int cnt = 0;  
        for(; first_contour != 0; first_contour = first_contour->h_next)  
        {  
            cnt++;  
            CvScalar color = CV_RGB(rand()&255, rand()&255, rand()&255);  
            cvDrawContours(dst, first_contour, color, color, 0, 2, CV_FILLED, cvPoint(0, 0));  
            CvRect rect = cvBoundingRect(first_contour,0);
            cvRectangle(dst, cvPoint(rect.x, rect.y), cvPoint(rect.x + rect.width, rect.y + rect.height),CV_RGB(255, 0, 0), 1, 8, 0);
        }  
 
        printf("the num of contours : %d\n", cnt);  
 
        cvNamedWindow( "Source", 1 );  
        cvShowImage( "Source", src );  
 
        cvNamedWindow( "dsw", 1 );  
        cvShowImage( "dsw", dsw );  
 
        cvNamedWindow( "Components", 1 );  
        cvShowImage( "Components", dst );  
 
		cvReleaseMemStorage(&storage);

		cvReleaseImage(&dsw);  // 应移至此处
		cvReleaseImage(&dst); // 应移至此处
 
        char c=cvWaitKey(10);
        if(c==27)
            break;   
    }
 
    cvDestroyWindow("Source");
    cvDestroyWindow("dsw");
    cvDestroyWindow("Components");
 
    //~ cvReleaseImage(&pFrame); //cvReleaseCapture会释放，千万别自己处理
    cvReleaseImage(&gsrc);
    cvReleaseImage(&src);
    
 
    //cvReleaseMemStorage(&storage);
    cvReleaseCapture(&pCapture);
 
    return 0;  
}