count the number of objects--物体计数

count the number of objects--物体计数

//Program to count the number of objects using morphology operations and the watershed transform

#include <opencv2/opencv.hpp>#include <opencv2/imgproc/imgproc.hpp>#include <opencv2/highgui/highgui.hpp>#include <iostream>using namespace std;using namespace cv;class objectCounter{private:Mat image,gray,markers,output;int count;public:objectCounter(Mat);   //constructorvoid get_markers();//function to get markers for watershed segmentationint count_objects();//function to implement watershed segmentation and count catchment basins};objectCounter::objectCounter(Mat _image){image=_image.clone();cvtColor(image,gray,CV_BGR2GRAY);imshow("image",image);}void objectCounter::get_markers(){//equalize histogram of image to improve contrastMat im_e;equalizeHist(gray,im_e);//imshow(im_e,im_e);//dilate to remove small black spotsMat strel=getStructuringElement(MORPH_ELLIPSE,Size(9,9));Mat im_d;dilate(im_e,im_d,strel);//imshow("im_d",im_d);//open and close to highlight objectsstrel=getStructuringElement(MORPH_ELLIPSE,Size(19,19));Mat im_oc;morphologyEx(im_d,im_oc,MORPH_OPEN,strel);morphologyEx(im_oc,im_oc,MORPH_CLOSE,strel);//imshow("im_oc",im_oc);//adaptive threshold to create binary imageMat th_a;adaptiveThreshold(im_oc,th_a,255,ADAPTIVE_THRESH_MEAN_C,THRESH_BINARY,105,0);//imshow("th_a",th_a);//erode binary image twice to separate regionsMat th_e;erode(th_a,th_e,strel,Point(-1,-1),2);//imshow("th_e",th_e);vector<vector<Point>> c,contours;vector<Vec4i> hierarchy;findContours(th_e,c,hierarchy,CV_RETR_CCOMP,CV_CHAIN_APPROX_NONE);//remove very small contoursfor(int idx=0;idx>=0;idx=hierarchy[idx][0])if(contourArea(c[idx])>20)contours.push_back(c[idx]);cout<<"Extracted:"<<contours.size()<<" contours"<<endl;count=contours.size();markers.create(image.rows,image.cols,CV_32SC1);for(int idx=0;idx<contours.size();idx++)drawContours(markers,contours,idx,Scalar::all(idx+1),-1,8);}int objectCounter::count_objects(){//colors generated randomly to make the output look prettyvector<Vec3b> colorTab;for (int i=0;i<count;i++){int b=theRNG().uniform(0,255);int g=theRNG().uniform(0,255);int r=theRNG().uniform(0,255);colorTab.push_back(Vec3b((uchar)b,(uchar)g,(uchar)r));}//watershed output imageMat wshed(markers.size(),CV_8UC3);//paint the watershed output imagefor (int i=0;i<markers.rows;i++){for (int j=0;j<markers.cols;j++){int index=markers.at<int>(i,j);if(index==-1)wshed.at<Vec3b>(i,j)=Vec3b(255,255,255);else if (index<=0 || index>count){wshed.at<Vec3b>(i,j)=Vec3b(0,0,0);}elsewshed.at<Vec3b>(i,j)=colorTab[index-1];}}//superimpose the watershed image with 50% transparence on the grayscale original imageMat imgGray;cvtColor(gray,imgGray,CV_GRAY2BGR);wshed=wshed*0.5+imgGray*0.5;imshow("Segmentation",wshed);return count;}int main(){Mat im=imread("E:\\图片\\YJ.jpg");objectCounter oc(im);oc.get_markers();int count=oc.count_objects();cout<<"Counted:"<<count<<" fruits"<<endl;while(char(waitKey(1))!='q')   { }return 0;}