由于项目需要,要对图像中的最大连通域进行标定,并且存储。首先需要使用cvFindCountour对边缘进行标定,其实它的原理就是连通域的边缘提取;其次就是对连通域进行大小判断找出最大的连通域;最后当然就是进行Rect并且ROI了。如果有需要可以进行存储。直接上源码吧。
#include "cv.h"#include "cxcore.h"#include "highgui.h" int main( int argc, char** argv ){ //声明IplImage指针 IplImage* pImg = cvLoadImage("black.bmp",0); IplImage* pContourImg = NULL; CvMemStorage * storage = cvCreateMemStorage(0); CvSeq * contour = 0; CvSeq *contmax = 0; int mode = CV_RETR_EXTERNAL; cvShowImage( "src", pImg ); //为轮廓显示图像申请空间 //3通道图像,以便用彩色显示 pContourImg = cvCreateImage(cvGetSize(pImg), IPL_DEPTH_8U, 3); //copy source image and convert it to BGR image cvCvtColor(pImg, pContourImg, CV_GRAY2BGR); //查找contour cvFindContours( pImg, storage, &contour, sizeof(CvContour), mode, CV_CHAIN_APPROX_SIMPLE, cvPoint(0,0)); //将轮廓画出 cvDrawContours(pContourImg, contour, CV_RGB(255,0,0), CV_RGB(255, 0, 0), 2, 2, 8, cvPoint(0,0)); int area,maxArea = 10;//设面积最大值大于10Pixel for(;contour;contour = contour->h_next) { area = fabs(cvContourArea( contour, CV_WHOLE_SEQ )); //获取当前轮廓面积 printf("area == %lf\n", area); if(area > maxArea) { contmax = contour; maxArea = area; } } CvRect aRect = cvBoundingRect( contmax, 0 ); cvSetImageROI( pContourImg,aRect); //显示图像 cvShowImage( "contour", pContourImg ); cvSaveImage("contour.bmp",pContourImg); cvWaitKey(0); //销毁窗口 cvDestroyWindow( "src" ); cvDestroyWindow( "contour" ); //释放图像 cvReleaseImage( &pImg ); cvReleaseImage( &pContourImg ); cvReleaseMemStorage(&storage); return 0;}
a. 二值化
b. 得到轮廓的个数
c. 将面积小于100的轮廓删除
d. 将宽、高 比例小于1的轮廓删除
e. 把面积最大的米粒用红色框框画出来
#include <stdio.h>#include <cv.h>#include <cxcore.h>#include <highgui.h>#pragma comment(lib, "ml.lib")#pragma comment(lib, "cv.lib")#pragma comment(lib, "cvaux.lib")#pragma comment(lib, "cvcam.lib")#pragma comment(lib, "cxcore.lib")#pragma comment(lib, "cxts.lib")#pragma comment(lib, "highgui.lib")#pragma comment(lib, "cvhaartraining.lib")int main( int argc, char** argv ) { IplImage* src; src=cvLoadImage("black.jpg",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 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 n=-1,m=0;//n为面积最大轮廓索引,m为迭代索引 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; n=m; } m++; // CvScalar color = CV_RGB( rand()&255, rand()&255, rand()&255 );//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 k=0;*/ int count=0; for( ; contour != 0; contour = contour->h_next ) { count++; double tmparea=fabs(cvContourArea(contour)); if (tmparea==maxarea /*k==n*/) { CvScalar color = CV_RGB( 255, 0, 0); cvDrawContours( dst, contour, color, color, -1, 1, 8 ); } /*k++;*/ } 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; } Opencv最大连通域进行标定并且存储:http://www.751com.cn/fanwen/lunwen_61912.html