OpenCV && C++ 02 - Create a Blank Image & Display

Posted 2022-11-14 zdfffg

Code

/*
作者：郑大峰
时间：2019年09月20日
环境：OpenCV 4.1.1 + VS2017
内容：Create a Blank Image & Display
*/

#include "pch.h"
#include <iostream>
#include <opencv2/opencv.hpp>

using namespace std;
using namespace cv;

int main()

    // Create a new image which consists of 
    // 800 x 600 of resolution (800 wide and 600 high)
    // image depth of 8 bits & 3 channels 
    // each pixels initialized to the value of (100, 250, 30) for Blue, Green and Red planes respectively
    Mat image(600, 800, CV_8UC3, Scalar(100, 250, 30));

    String windowName = "Window with Blank Image";
    namedWindow(windowName);
    imshow(windowName, image);

    waitKey(0);
    destroyWindow(windowName);

    return 0;

Result

Explanation

Mat::Mat(int rows, int cols, int type, const Scalar& s)

This constructor will create a Mat object with specified number of rows and number of cols and initialize each element with the value given in s.

@param rows Number of rows in a 2D array.
@param cols Number of columns in a 2D array.
@param type Array type. Use CV_8UC1, ..., CV_64FC4 to create 1-4 channel matrices, or CV_8UC(n), ..., CV_64FC(n) to create multi-channel (up to CV_CN_MAX channels) matrices.
@param s An optional value to initialize each matrix element with. To set all the matrix elements to the particular value after the construction, use the assignment operator Mat::operator=(const Scalar& value) .