opencv查找二值图像最大连通区域

【核心代码】

#include "cv.h"
#include "cxcore.h"
#include "highgui.h"

CvRect FindMaxContour(IplImage *pImg)
{

	IplImage* pContourImg = NULL;
	CvMemStorage * storage = cvCreateMemStorage(0);
	CvSeq * contour = 0;
	CvSeq *contmax = 0;
	int mode = CV_RETR_EXTERNAL;

	int area,maxArea = 10;//设面积最大值大于10Pixel
	CvRect aRect;

	cvFindContours( pImg, storage, &contour, sizeof(CvContour),mode, CV_CHAIN_APPROX_SIMPLE, cvPoint(0,0));


	for(;contour;contour = contour->h_next)
	{
		area = fabs(cvContourArea( contour, CV_WHOLE_SEQ )); //获取当前轮廓面积
		//printf("area == %d\n", area);
		if(area > maxArea)
		{
			contmax = contour;
			maxArea = area;
		}
	}

	aRect = cvBoundingRect( contmax, 0 );
	return aRect;

}



int main( int argc, char** argv )
{
	//声明IplImage指针
	IplImage* pImg = cvLoadImage("black.jpg",0);
	IplImage* pImg_tmp = cvLoadImage("black.jpg",0);
	pImg_tmp =cvCreateImage(cvGetSize(pImg),IPL_DEPTH_8U,1);
	cvCopy(pImg,pImg_tmp);
	CvRect aRect;

	aRect = FindMaxContour(pImg_tmp);

	

	CvPoint pt1; 
	CvPoint pt2;
	pt1.x = aRect.x;
	pt1.y = aRect.y;
	pt2.x = aRect.x   aRect.width;
	pt2.y = aRect.y   aRect.height;

	cvRectangle(pImg,pt1,pt2,CV_RGB(255,255,255));
	
	//显示图像
	cvShowImage( "contour", pImg );

	cvWaitKey(0);

	//销毁窗口
	cvDestroyWindow( "src" );
	cvDestroyWindow( "contour" );
	//释放图像
	cvReleaseImage( &pImg );

	return 0;
}