//take_photo.cpp

#include<opencv2/opencv.hpp>

using namespace cv;

using namespace std;

void take_photo() {

    VideoCapture cap(); //打开摄像头

    if (!cap.isOpened())

        return;

    //加载级联检测器

    CascadeClassifier cascade;

    cascade.load("F:/opencv3.2/Release_x64/etc/haarcascades/haarcascade_frontalface_alt_tree.xml");

    Mat frame;

    vector<Rect>faces;

    int count = ;

    while (cap.read(frame))        //相当于cap >> frame

    {

        cascade.detectMultiScale(frame, faces, 1.1, , , Size(, ), Size(, ));//检测是否有人脸

        for (int i = ; i < faces.size(); i++)

        {

            if (count %  == ) {    //每10帧保存一次人脸图像

                Mat dst;

                resize(frame(faces[i]), dst, Size(, ));//设置人脸图像大小

                cvtColor(dst, dst, COLOR_BGR2GRAY);//转为灰度图节省计算

                imwrite(format("att_faces/s41/pic%d.jpg", count / ), dst);

            }

            rectangle(frame, faces[i], Scalar(, , ));

        }

        imshow("video", frame);

        //按下任意键退出摄像头（waitkey在本系统环境下默认为255）,或者是保存了20张人脸图片后,退出

        if (waitKey() !=  || count / >)

            break;

        count++;

    }

    cap.release();

    destroyAllWindows();//关闭所有窗口

}

//face_recognition.cpp

#include <opencv2/opencv.hpp>

#include <opencv2/face.hpp>

using namespace cv;

using namespace cv::face;

using namespace std;

double face_recognition() {

    //读取文件，转换为数据流

    string filename = string("at.txt");

    ifstream file(filename.c_str(), ifstream::in);

    if (!file)

        cout << "error" << endl;

    string line, path, classlabel;

    vector<Mat>image;

    vector<int>labels;

    char separator = ';';

    while (getline(file, line))

    {

        stringstream liness(line);

        getline(liness, path, separator);

        getline(liness, classlabel);

        if (!path.empty() && !classlabel.empty())

        {

            //cout << "path:" << path<< endl;

            image.push_back(imread(path, ));

            labels.push_back(atoi(classlabel.c_str()));

        }

    }

    if (image.size() <  || labels.size() < )

        cout << "invalid image path..." << endl;

    //最后一个人为测试样本

    Mat testSample = image[image.size() - ];

    int testLabel = labels[labels.size() - ];

    image.pop_back();

    labels.pop_back();

    //EigenFace算法的模型训练

    Ptr<BasicFaceRecognizer>model = createEigenFaceRecognizer();

    model->train(image, labels);

    //对样本进行识别

    int predictLabel = model->predict(testSample);

    cout << "actual label:" << testLabel << ",predict label:" << predictLabel << endl;

    //加载级联检测器

    CascadeClassifier cascade;

    cascade.load("haarcascade_frontalface_alt_tree.xml");//识别时用alt_tree分类器，宁可漏检也不误检

    //打开摄像头

    VideoCapture cap();

    if (!cap.isOpened())

        cout << "error...";

    Mat frame;

    vector<Rect>faces;

    int correct = , total = ;

    while (cap.read(frame))        //相当于cap >> frame，读取摄像头的每一帧

    {

        cascade.detectMultiScale(frame, faces, 1.1, , , Size(, ), Size(, ));//检测是否有人脸

        for (int i = ; i < faces.size(); i++)

        {

            Mat roi = frame(faces[i]);

            cvtColor(roi, roi, COLOR_BGR2GRAY);

            resize(roi, testSample, testSample.size());

            int label = model->predict(testSample);

            rectangle(frame, faces[i], Scalar(, , ));

            if (label == )

            {

                putText(frame, "ZhangChunFu", faces[i].tl(), FONT_HERSHEY_COMPLEX, 1.0, Scalar(, , ));

                correct++;

            }

            else

                putText(frame, format("%d", label), faces[i].tl(), CV_FONT_HERSHEY_SIMPLEX, 0.8, Scalar(, , ));

        }

        total++;

        imshow("人脸识别——MR.Zhang", frame);

        if (waitKey() == )

            break;

    }

    cap.release();

    destroyAllWindows();//关闭所有窗口

    waitKey();

    double rate = (1.0*correct) / total;

    return rate;//返回正确率

}

//main.cpp

#include <opencv2/opencv.hpp>

#include <opencv2/face.hpp>

#include <iostream>

using namespace cv;

using namespace cv::face;

using namespace std;

void take_photo();

double face_recognition();

void main() {

    int flag;

    double rate;

    cout << "欢迎使用人脸识别系统(1代表录入人脸，2代表识别人脸），请输入您的选择：" << endl;

    cin >> flag;

    cout << "请稍等片刻……"<<endl;

    switch (flag)

    {

    case :take_photo();

        return;

    case :

        rate=face_recognition();

        break;

    default:

        break;

    }

    cout << "识别率：" << rate << endl;

    system("pause");

}