基于Opencv的人脸识别

人脸识别

1. 当在阅读书籍opencv3时，偶遇人脸识别这一概念，通过网上查阅得知人脸识别是生物特征识别的最新应用。
2. 在此书籍引导下，写了一个最基本的人脸识别
3. 期间有一个问题需要注意，再往工程目录导入xml文件是注意不要导错，应该是这两个haarcascade_frontalface_alt.xml和haarcascade_eye.xml

#include<opencv2/objdetect.hpp>#include<opencv2/videoio.hpp>#include<opencv2/highgui.hpp>#include<opencv2/imgproc.hpp>#include<iostream>#include<stdio.h>using namespace cv;using namespace std;String face_cascade_name = "haarcascade_frontalface_alt.xml";              String eyes_cascade_name = "haarcascade_eye.xml";                CascadeClassifier face_cascade;CascadeClassifier eyes_cascade;String window_name = "Capture - Face detection";void detectAndDisplay(Mat frame){    std::vector<Rect> faces;    Mat frame_gray;    cvtColor(frame, frame_gray, COLOR_BGR2GRAY);    equalizeHist(frame_gray, frame_gray);    //-- Detect faces    face_cascade.detectMultiScale(frame_gray, faces, 1.1, 2, 0 | CASCADE_SCALE_IMAGE, Size(30, 30));    for (size_t i = 0; i < faces.size(); i++)    {        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), 4, 8, 0);//椭圆形        Mat faceROI = frame_gray(faces[i]);        std::vector<Rect> eyes;        //-- In each face, detect eyes        eyes_cascade.detectMultiScale(faceROI, eyes, 1.1, 2, 0 | CASCADE_SCALE_IMAGE, Size(30, 30));        for (size_t 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), 4, 8, 0);        }    }    //-- Show what you got    imshow(window_name, frame);}int main(){    VideoCapture capture(0);    Mat frame;    //-- 1. Load the cascades    if (!face_cascade.load(face_cascade_name)){ printf("--(!)Error loading face cascade\n"); return -1; };    if (!eyes_cascade.load(eyes_cascade_name)){ printf("--(!)Error loading eyes cascade\n"); return -1; };    //-- 2. Read the video stream    if (!capture.isOpened()) { printf("--(!)Error opening video capture\n"); return -1; }    while (capture.read(frame))    {        if (frame.empty())        {            printf(" --(!) No captured frame -- Break!");            break;        }        detectAndDisplay(frame);        int c = waitKey(10);        if ((char)c == 27) break;    }    return 0;}

效果图