opencv打开摄像头

#include "opencv2/opencv.hpp"
#include <string>
#include <iostream>

using namespace cv;
using namespace std;

int main()
{
    VideoCapture inputVideo(0);
    if (!inputVideo.isOpened())
    {
        cout << "Could not open the input video " << endl;
        return -1;
    }
    Mat frame;
    string imgname;
    int f = 1;
    while (1) //Show the image captured in the window and repeat
    {
        inputVideo >> frame;              // read
        if (frame.empty()) break;         // check if at end
        imshow("Camera", frame);
        char key = waitKey(1);
        if (key == 27)break;
        if (key == 'q' || key == 'Q')
        {
            imgname = to_string(f++) + ".jpg";
            imwrite(imgname, frame);
        }
    }
    cout << "Finished writing" << endl;
    return 0;
}

cmakelist.txt

project(fan)
CMAKE_MINIMUM_REQUIRED(VERSION 3.10)

find_package(OpenCV REQUIRED)
find_package(OpenCV QUIET COMPONENTS core highgui imgproc imgcodecs videoio)

AUX_SOURCE_DIRECTORY(./ DIR_SRCS)

include_directories(${OpenCV_INCLUDE_DIRS})
include_directories(/home/dji/文档/RM2021/capture/MVS/inlude)
link_directories(${OpenCV_LIBRARY_DIRS})
link_directories("/home/dji/文档/RM2021/capture/MVS/lib/aarch64")
link_libraries("/home/dji/文档/RM2021/capture/MVS/lib/aarch64/libMvCameraControl.so")
SET(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/bin)
add_compile_options(-std=c++11)
#-Wall -Werror
ADD_EXECUTABLE(fan ${DIR_SRCS})
target_link_libraries(fan ${OpenCV_LIBS})
target_link_libraries(fan -lpthread -luuid -lMvCameraControl -lX11 )
target_link_libraries(fan libMvCameraControl.so)

延时：

#include <stdio.h>

int main()
{
    printf("hello\n");

        sleep(1);  //延迟1秒

    printf("world\n");

    return 0;
}