基于opencv3的人脸检测

目前opencv3中已经有人脸检测的类了，只要调用函数库的类就行

该程序需要两个xml文件，分别是haarcascade_frontalface_alt.xml和haarcascade_eye_tree_eyeglasses.xml，它们分别是已经通过了大量训练且能检测出人脸和眼睛了，只要调用即可。

#include"opencv2/objdetect/objdetect.hpp"#include"opencv2/highgui/highgui.hpp"#include"opencv2/imgproc/imgproc.hpp"#include"opencv2/core/core.hpp"#include"iostream"using namespace std;using namespace cv;void detection(Mat frame);String face_cascade_name = "haarcascade_frontalface_alt.xml";String eyes_cascade_name = "haarcascade_eye_tree_eyeglasses.xml";CascadeClassifier face_cascade;CascadeClassifier eyes_cascade;int main(){    if (!face_cascade.load(face_cascade_name))        cerr << "Loading haarcascade_frontalface_alt.xml error"<<endl;    if (!eyes_cascade.load(eyes_cascade_name))        cerr << "Loading haarcascade_eye_tree_eyeglasses.xml error" << endl;    VideoCapture capture(0);    Mat frame;    while (1)    {        capture >> frame;        if (!frame.data)            cerr << "Opening capture error!" << endl;        detection(frame);        waitKey(15);    }    return 0;}void detection(Mat frame){    vector<Rect> faces;    Mat frame_gray;    cvtColor(frame, frame_gray, COLOR_BGR2GRAY);    equalizeHist(frame_gray, frame_gray);//直方图均匀化    face_cascade.detectMultiScale(frame_gray, faces, 1.1, 2, 0 | 0 | CV_HAAR_SCALE_IMAGE, Size(30, 30));//人脸检测    for (int i = 0; i < faces.size(); i++)    {        //用椭圆圈出脸        Point center(faces[i].x + faces[i].width / 2, faces[i].y + faces[i].height / 2);        ellipse(frame, center, Size(faces[i].width / 2, faces[i].height / 2), 0, 0, 360, Scalar(255, 0, 255), 2, 8, 0);        //用圆圈出眼睛        Mat face_roi = frame_gray(faces[i]);        vector<Rect> eyes;        eyes_cascade.detectMultiScale(face_roi, eyes, 1.1, 2, 0 | CV_HAAR_SCALE_IMAGE, Size(30, 30));//在脸中检测眼睛        for (int j = 0; j < eyes.size(); j++)        {            Point eye_center(faces[i].x + eyes[j].x + eyes[j].width / 2, faces[i].y + eyes[j].y + eyes[j].height / 2);            int radius = cvRound((eyes[j].width + eyes[j].height)*0.25);            circle(frame, eye_center, radius, Scalar(255, 0, 0), 3, 8, 0);        }    }    //-- 显示最终效果图    imshow("picture", frame);}