OpenCV计算连通区域数目与最大连通区域并标示出

#include <stdio.h>  
#include <cv.h>  
#include <highgui.h>  
  
#pragma comment(lib, "cv.lib")  
#pragma comment(lib, "cxcore.lib")  
#pragma comment(lib, "highgui.lib")  
  
int main( int argc, char** argv )    
{  
    IplImage* src = cvLoadImage(".\\wind.png", CV_LOAD_IMAGE_GRAYSCALE);  
    IplImage* dst = cvCreateImage(cvGetSize(src), 8, 3);  
    CvMemStorage* storage = cvCreateMemStorage(0);  
    CvSeq* contour = 0;  
    cvThreshold(src, src,120, 255, CV_THRESH_BINARY);   // 二值化  
    cvNamedWindow("Source", 1);  
    cvShowImage("Source", src);  
    // 提取轮廓  
    int contour_num = cvFindContours(src, storage, &contour, sizeof(CvContour), CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE);  
    cvZero(dst);        // 清空数组  
    CvSeq *_contour = contour;   
    double maxarea = 0;  
    double minarea = 100;  
    int m = 0;  
    for( ; contour != 0; contour = contour->h_next )    
    {    
  
        double tmparea = fabs(cvContourArea(contour));  
        if(tmparea < minarea)     
        {    
            cvSeqRemove(contour, 0); // 删除面积小于设定值的轮廓  
            continue;  
        }    
        CvRect aRect = cvBoundingRect( contour, 0 );   
        if ((aRect.width/aRect.height)<1)    
        {    
            cvSeqRemove(contour, 0); //删除宽高比例小于设定值的轮廓  
            continue;  
        }    
        if(tmparea > maxarea)    
        {    
            maxarea = tmparea;  
        }    
        m++;  
        // 创建一个色彩值  
        CvScalar color = CV_RGB( 0, 255, 255 );  
  
        //max_level 绘制轮廓的最大等级。如果等级为0，绘制单独的轮廓。如果为1，绘制轮廓及在其后的相同的级别下轮廓  
        //如果值为2，所有的轮廓。如果等级为2，绘制所有同级轮廓及所有低一级轮廓，诸此种种  
        //如果值为负数，函数不绘制同级轮廓，但会升序绘制直到级别为abs(max_level)-1的子轮廓  
        cvDrawContours(dst, contour, color, color, -1, 1, 8);   //绘制外部和内部的轮廓  
    }    
    contour = _contour;  
    int count = 0;  
    for(; contour != 0; contour = contour->h_next)  
    {    
        count++;  
        double tmparea = fabs(cvContourArea(contour));  
        if (tmparea == maxarea)    
        {    
            CvScalar color = CV_RGB( 255, 0, 0);  
            cvDrawContours(dst, contour, color, color, -1, 1, 8);  
        }    
    }    
    printf("The total number of contours is:%d", count);  
    cvNamedWindow("Components", 1);  
    cvShowImage("Components", dst);  
    cvWaitKey(0);  
    cvDestroyWindow("Source");  
    cvReleaseImage(&src);  
    cvDestroyWindow("Components");  
    cvReleaseImage(&dst);  
  
    return 0;  
}  

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