opencv之求各连通区域内目标的最小外接矩形及其长、宽.doc

10、 最小外接矩形及长宽的求法 #include cv.h#include highgui.h#include #include #include otsu.hint main(int argc,char* argv)IplImage *src,*gray,*bw,*dst; CvMemStorage* storage=cvCreateMemStorage(0);CvSeq* contour=0;char* filename=argc=2?argv1:5.jpg;if(!filename)printf(cant open the file:%dn,filename); src=cvLoadImage(filename,1);cvNamedWindow(image,1);cvShowImage(image,src); gray=cvCreateImage(cvSize(src-width,src-height),src-depth,1);cvCvtColor(src,gray,CV_BGR2GRAY); 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：%dnn,hei,wid);cvNamedWindow(image2,1); cvShowImage(image2,gray); bw=cvCreateImage(cvGetSize(src),IPL_DEPTH_8U,1); otsu(gray,bw); 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_CCOMP,CV_CHAIN_APPROX_SIMPLE); for(;contour!=0;contour=contour-h_next)CvBox2D rect=cvMinAreaRect2(contour,storage);CvPoint2D32f rect_pts04;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 *ptint npts = 4,k=0;int aaa=0,bbb=0;CvPoint rect_pts4, *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; i4; i+)rect_ptsi= cvPointFrom32f(rect_pts0i);printf(%d %dn,rect_ptsi.x,rect_ptsi.y);aaa=(int)sqrt(pow(rect_pts0.x-rect_pts1.x),2)+pow(rect_pts0.y-rect_pts1.y),2);bbb=(int)sqrt(pow(rect_pts0.x-rect_pts3.x),2)+pow(rect_pts0.y-rect_pts3.y),2);if(aaabbb)k=aaa;aaa=bbb;bbb=k;printf(最小外接矩形的长为：%d，宽为：%d。nn,aaa,bbb);/chang=rect_pts0-rect_pts3;/kuan=rect_pts0-rect_pts1;/printf(最小外接矩形的长为：%d,宽为：%dn,chang,kuan);/画出BoxcvPolyLine(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(im