C++通过OpenCV打开摄像头Demo

#include "opencv2/core.hpp"
#include "opencv2/imgproc.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/videoio.hpp"
#include 
#include 
using namespace cv;
using namespace std;
void drawText(Mat & image);//声明标志
int main()
{
    cout << "开始调用OpenCV " << CV_VERSION << endl;
    Mat image;
    VideoCapture capture;
    capture.open(0);//打开默认的摄像头
                    //0号为默认摄像头
    if(capture.isOpened())//capture.isOpened()打开摄像头
    {
        cout << "打开摄像头" << endl;
        for(;;)
        {
            capture >> image;
            if(image.empty())
                break;
            drawText(image);//调用标志
            imshow("简单的摄像头调用", image);//图像显示页面的标题
            if(waitKey(10) >= 0)
                break;
        }
    }
    else
    {
        cout << "无捕获" << endl;
        image = Mat::zeros(480, 640, CV_8UC1);
        drawText(image);
        imshow("简单的摄像头调用", image);//图像显示页面的标题
        waitKey(0);
    }
    return 0;
}
void drawText(Mat & image)
{
    putText(image,"01123",//视频标志
            Point(20, 50),//标志在视频上的相对位置
            FONT_HERSHEY_COMPLEX, 1, // 字体和规模
            Scalar(5, 77, 25), // 字体颜色
            1, LINE_AA); // 线厚度和类型
}