opencv官方源码之人脸识别

首先，这里路径记得改一下，参考一下博客

 OpenCV3编程入门---人脸识别示例：objectDetection报错“Error loading face cascade”_Burette_Lee的博客-CSDN博客

#include "opencv2/objdetect.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/imgproc.hpp"

#include

using namespace std;
using namespace cv;

void detectAndDisplay(Mat frame);

CascadeClassifier face_cascade;
CascadeClassifier eyes_cascade;

int main(int argc, const char** argv)
{
    CommandLineParser parser(argc, argv,
        "{help h||}"
        "{face_cascade|C:/Users/离子键/opencv/sources/data/haarcascades/haarcascade_frontalface_alt.xml|Path to face cascade.}"
        "{eyes_cascade|C:/Users/离子键/opencv/sources/data/haarcascades/haarcascade_eye_tree_eyeglasses.xml|Path to eyes cascade.}"
        "{camera|0|Camera device number.}");

    parser.about("nThis program demonstrates using the cv::CascadeClassifier class to detect objects (Face + eyes) in a video stream.n"
        "You can use Haar or LBP features.nn");
    parser.printMessage();

    String face_cascade_name = parser.get("face_cascade");
    String eyes_cascade_name = parser.get("eyes_cascade");

    //-- 1. Load the cascades
    if (!face_cascade.load(face_cascade_name))
    {
        cout << "--(!)Error loading face cascaden";
        return -1;
    };
    if (!eyes_cascade.load(eyes_cascade_name))
    {
        cout << "--(!)Error loading eyes cascaden";
        return -1;
    };

    int camera_device = parser.get("camera");
    VideoCapture capture;
    //-- 2. Read the video stream
    capture.open(camera_device);
    if (!capture.isOpened())
    {
        cout << "--(!)Error opening video capturen";
        return -1;
    }

    Mat frame;
    while (capture.read(frame))
    {
        if (frame.empty())
        {
            cout << "--(!) No captured frame -- Break!n";
            break;
        }

        //-- 3. Apply the classifier to the frame
        detectAndDisplay(frame);

        if (waitKey(10) == 27)
        {
            break; // escape
        }
    }
    return 0;
}

void detectAndDisplay(Mat frame)
{
    Mat frame_gray;
    cvtColor(frame, frame_gray, COLOR_BGR2GRAY);
    equalizeHist(frame_gray, frame_gray);

    //-- Detect faces
    std::vector faces;
    face_cascade.detectMultiScale(frame_gray, faces);

    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);

        Mat faceROI = frame_gray(faces[i]);

        //-- In each face, detect eyes
        std::vector eyes;
        eyes_cascade.detectMultiScale(faceROI, eyes);

        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);
        }
    }

    //-- Show what you got
    imshow("Capture - Face detection", frame);
}