在OpenCV中保存检测到的面部图像

Question

我有一个代码可以检测面部并将它们的多个裁剪区域图像保存到文件路径中。在我实际关闭程序之前，我的代码不会停止保存检测到的面部图像。每隔一秒就会在网络摄像头上检测到一张脸，我的代码会保存6张脸部图像。

是否可以保存每张脸只检测到一张图像？例如，如果有一个面，只有一个图像，如果有两个面，则保存两个面的图像等。我的代码在下面。任何人都可以帮助我吗？

#include "opencv2/objdetect/objdetect.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
#include <stdio.h>

using namespace std;
using namespace cv;

void detectAndDisplay(Mat frame);

string face_cascade_name = "C:\\opencv\\sources\\data\\haarcascades\\haarcascade_frontalface_alt2.xml";
CascadeClassifier face_cascade;
string window_name = "Window";
int filenumber; 
string filename;


int main(void)
{
    VideoCapture capture(0);

    if (!capture.isOpened())  
        return -1;

    if (!face_cascade.load(face_cascade_name))
    {
        cout << "error" << endl;
        return (-1);
    };

    Mat frame;

    for (;;)
    {
        capture >> frame;

        if (!frame.empty())
        {
            detectAndDisplay(frame);
        }
        else
        {
            cout << "error2" << endl;
            break;
        }

        int c = waitKey(10);

        if (27 == char(c))
        {
            break;
        }
    }

    return 0;
}

void detectAndDisplay(Mat frame)
{
    std::vector<Rect> faces;
    Mat frame_gray;
    Mat crop;
    Mat res;
    Mat gray;
    string text;
    stringstream sstm;

    cvtColor(frame, frame_gray, COLOR_BGR2GRAY);
    equalizeHist(frame_gray, frame_gray);

    face_cascade.detectMultiScale(frame_gray, faces, 1.1, 2, 0 | CASCADE_SCALE_IMAGE, Size(30, 30));

    cv::Rect roi_b;
    cv::Rect roi_c;

    size_t ic = 0; 
    int ac = 0; 

    size_t ib = 0; 
    int ab = 0; 

    for (ic = 0; ic < faces.size(); ic++) 

    {
        roi_c.x = faces[ic].x;
        roi_c.y = faces[ic].y;
        roi_c.width = (faces[ic].width);
        roi_c.height = (faces[ic].height);

        ac = roi_c.width * roi_c.height; 

        roi_b.x = faces[ib].x;
        roi_b.y = faces[ib].y;
        roi_b.width = (faces[ib].width);
        roi_b.height = (faces[ib].height);


        crop = frame(roi_b);
        resize(crop, res, Size(128, 128), 0, 0, INTER_LINEAR); 
        cvtColor(crop, gray, CV_BGR2GRAY); 

        filename = "C:\\Users\\Desktop\\Faces\\face";
        stringstream ssfn;
        ssfn << filename.c_str() << filenumber << ".jpg";
        filename = ssfn.str();
        cv::imwrite(filename, res); 
        filenumber++;


        Point pt1(faces[ic].x, faces[ic].y); 
        Point pt2((faces[ic].x + faces[ic].height), (faces[ic].y + faces[ic].width));
        rectangle(frame, pt1, pt2, Scalar(0, 255, 0), 2, 8, 0);
    }


    sstm << "Crop area size: " << roi_b.width << "x" << roi_b.height << " Filename: " << filename;
    text = sstm.str();

    if (!crop.empty())
    {
        imshow("detected", crop);
    }
    else
        destroyWindow("detected");

}