[opencv]识别人脸和眼睛

本文的目标是实现本地打开一张图片并对其中的人脸和眼睛进行识别。

代码如下：

#include "stdafx.h"
#include 
#include 
#include "opencv2/objdetect/objdetect.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
using namespace std;
using namespace cv;

/** Function Headers */
void detectAndDisplay(Mat frame);

/** Global variables */
String face_cascade_name = "haarcascade_frontalface_alt.xml";
String eyes_cascade_name = "haarcascade_eye_tree_eyeglasses.xml";
CascadeClassifier face_cascade;
CascadeClassifier eyes_cascade;
string window_name = "Face detection";

/** @function main */
int main(int argc, const char** argv)
{
    CvCapture* capture;
    Mat frame;

    //1. Load the cascades
    if (!face_cascade.load(face_cascade_name)){ printf("--(!)Error loading\n"); return -1; };
    if (!eyes_cascade.load(eyes_cascade_name)){ printf("--(!)Error loading\n"); return -1; };
    //2. read image for detection
    Mat img= imread("pic.png",CV_LOAD_IMAGE_UNCHANGED);
    if (img.empty())  // 3. handle exception
    {
        cout << "Cannot open the img" << endl;
        return -1;
    }
    cout << " open the img successfully" << endl;
    detectAndDisplay(img);
    waitKey(60000);
    return 0;
}

/** @function detectAndDisplay */
void detectAndDisplay(Mat frame)
{
    std::vector faces;
    Mat frame_gray;

    cvtColor(frame, frame_gray, CV_BGR2GRAY);
    equalizeHist(frame_gray, frame_gray);

    //-- Detect faces
    face_cascade.detectMultiScale(frame_gray, faces, 1.1, 2, 0 | CV_HAAR_SCALE_IMAGE, Size(30, 30));

    for (size_t i = 0; i < faces.size(); i++)
    {
        Point center(faces[i].x + faces[i].width*0.5, faces[i].y + faces[i].height*0.5);
        ellipse(frame, center, Size(faces[i].width*0.5, faces[i].height*0.5), 0, 0, 360, Scalar(255, 0, 255), 4, 8, 0);

        Mat faceROI = frame_gray(faces[i]);
        std::vector eyes;

        //-- In each face, detect eyes
        eyes_cascade.detectMultiScale(faceROI, eyes, 1.1, 2, 0 | CV_HAAR_SCALE_IMAGE, Size(30, 30));

        for (size_t j = 0; j < eyes.size(); j++)
        {
            Point center(faces[i].x + eyes[j].x + eyes[j].width*0.5, faces[i].y + eyes[j].y + eyes[j].height*0.5);
            int radius = cvRound((eyes[j].width + eyes[j].height)*0.25);
            circle(frame, center, radius, Scalar(255, 0, 0), 4, 8, 0);
        }
    }
    //-- Show what you got
    imshow(window_name, frame);
}

实现效果如下：
1。原始图片：

2。处理后图片：