opencv 连通区域的最小外接矩形

#include "cv.h"
#include "highgui.h"
#include <stdio.h>
#include <math.h>
//#include "otsu.h"

int main(int argc,char** argv)
{
IplImage *src,*gray,*bw,*dst;
CvMemStorage* storage=cvCreateMemStorage(0);
CvSeq* contour=0;

char* filename=argc==2?argv[1]:"5.jpg";

if(!filename)
printf("can't open the file:%d\n",filename);

src=cvLoadImage("D:\\xsz\\Debug\\图片\\3.jpg",1);

cvNamedWindow("image",1);
cvShowImage("image",src);

gray=cvCreateImage(cvSize(src->width,src->height),src->depth,1);
cvCvtColor(src,gray,CV_BGR2GRAY);
int hei,wid;
hei=gray->height;//注意此处是gray，otsu中要用到hei,wid,已在otsu.h中全局定义；
wid=gray->width;
printf("图像的高为：%d,宽为：%d\n\n",hei,wid);

cvNamedWindow("image2",1);
cvShowImage("image2",gray);

bw=cvCreateImage(cvGetSize(src),IPL_DEPTH_8U,1);
cvThreshold(gray,bw,128,255,CV_THRESH_BINARY_INV);

cvNamedWindow("image4",1);
cvShowImage("image4",bw);

//	wb=cvCloneImage(bw);
//  cvNot(bw,wb);  只有当目标区域为黑色背景时候，才对其取反。

dst=cvCloneImage(src);
cvFindContours(bw,storage,&contour,sizeof(CvContour),CV_RETR_TREE,CV_CHAIN_APPROX_SIMPLE);
for(;contour!=0;contour=contour->h_next)

{	CvBox2D rect=cvMinAreaRect2(contour,storage);

CvPoint2D32f rect_pts0[4];
cvBoxPoints(rect, rect_pts0);

//因为cvPolyLine要求点集的输入类型是CvPoint**
//所以要把 CvPoint2D32f 型的 rect_pts0 转换为 CvPoint 型的 rect_pts
//并赋予一个对应的指针 *pt
int npts = 4,k=0;
int aaa=0,bbb=0;
CvPoint rect_pts[4], *pt = rect_pts;

printf("连通区域最小外接矩形顶点坐标分别为:\n");
for (int i=0; i<4; i++)
{
rect_pts[i]= cvPointFrom32f(rect_pts0[i]);
printf("%d %d\n",rect_pts[i].x,rect_pts[i].y);
aaa=(int)sqrt((pow((rect_pts[0].x-rect_pts[1].x),2)+pow((rect_pts[0].y-rect_pts[1].y),2)));
bbb=(int)sqrt((pow((rect_pts[0].x-rect_pts[3].x),2)+pow((rect_pts[0].y-rect_pts[3].y),2)));

if(aaa<bbb)
{
k=aaa;
aaa=bbb;
bbb=k;
}

}
printf("最小外接矩形的长为：%d，宽为：%d。\n\n",aaa,bbb);

//chang=rect_pts[0]-rect_pts[3];
//kuan=rect_pts[0]-rect_pts[1];
//printf("最小外接矩形的长为：%d,宽为：%d\n",chang,kuan);

//画出Box
cvPolyLine(dst, &pt, &npts, 1, 1, CV_RGB(255,0,0), 1);
}
cvNamedWindow("image5",1);
cvShowImage("image5",dst);

cvWaitKey(0);//注意此句放的位置，放的不对则。。。

cvDestroyWindow("image");
cvDestroyWindow("image2");
cvDestroyWindow("image4");
cvDestroyWindow("image5");

cvReleaseImage(&src);
cvReleaseImage(&gray);
cvReleaseImage(&bw);
cvReleaseImage(&dst);

return 0;
}