#include <opencv2/opencv.hpp>
#include <opencv2/xfeatures2d.hpp>
#include<opencv2/face.hpp>
#include<iostream>
#include<math.h>
#include <string> 
#include<fstream> 

using namespace cv::face;
using namespace cv;
using namespace std;
using namespace cv::xfeatures2d;

int
 
 main() {
    VideoCapture capture;
    capture.open("C:/Users/Administrator/Desktop/pic/3.avi");
    Ptr<BackgroundSubtractor>pMOG2 = createBackgroundSubtractorMOG2();
    Mat kernel = getStructuringElement(MORPH_RECT, Size(3, 3));
    vector<vector<Point>>contours;
    vector<Vec4i>
 
 hireachy;
    Mat frame, gray, mogmask;
    while (capture.read(frame)) {
        imshow("src", frame);
        pMOG2->apply(frame, mogmask);
        threshold(mogmask, mogmask, 100, 255, THRESH_BINARY);//二值化
        morphologyEx(mogmask, mogmask, MORPH_OPEN, kernel);
        findContours(mogmask, contours, hireachy, RETR_EXTERNAL, CHAIN_APPROX_SIMPLE, Point(0
 
, 0));
        cvtColor(mogmask, mogmask, COLOR_GRAY2BGR);
        int count = 0;
        char numText[8];
        for (size_t t = 0; t < contours.size(); t++) {
            double area = contourArea(contours[t]);//獲取輪廓的面積
            if (area < 100) continue;//忽略面積小的
            Rect selection = boundingRect(contours[t]);
            if (selection.width < 10 || selection.height < 10) contours;
            count++;
            rectangle(mogmask, selection, Scalar(0, 0, 255), 2);
            sprintf_s(numText, "%d", count);
            putText(mogmask, numText, Point(selection.x, selection.y), CV_FONT_NORMAL, FONT_HERSHEY_PLAIN, Scalar(255, 0, 0));
        }
        cout << "nini";
        imshow("mogmask", mogmask);
    }
    capture.release();
    waitKey(0);
}

結果：