OpenCV C++ Program to create a single colored blank image

The following is the explanation to the C++ code to create a single colored blank image in C++ using the tool OpenCV. Things to know: 

(1) The code will only compile in Linux environment.

(2) To run in windows, please use the file: 'blank.o' and run it in cmd. However if it does not run (problem in system architecture) then compile it in windows by making suitable and obvious changes to the code like: Use <iostream.h> in place of <iostream>.

(3) Compile command: g++ -w blank.cpp -o blank `pkg-config --libs opencv` (4) Run command: ./article Before you run the code, please make sure that you have OpenCV installed on your system. Code Snippet:

// Title: Create a coloured image in C++ using OpenCV.

// highgui - an easy-to-use interface to 
// video capturing, image and video codecs,
// as well as simple UI capabilities.
#include "opencv2/highgui/highgui.hpp"

// Namespace where all the C++ OpenCV 
// functionality resides. 
using namespace cv;

// For basic input / output operations. 
// Else use macro 'std::' everywhere.
using namespace std;

int main()
{
 // To create an image
 // CV_8UC3 depicts : (3 channels,8 bit image depth
 // Height = 500 pixels, Width = 1000 pixels
 // (0, 0, 100) assigned for Blue, Green and Red 
 // plane respectively. 
 // So the image will appear red as the red 
 // component is set to 100.
 Mat img(500, 1000, CV_8UC3, Scalar(0,0, 100));
 
 // check whether the image is loaded or not
 if (img.empty()) 
 {
 cout << "\n Image not created. You"
 " have done something wrong. \n";
 return -1; // Unsuccessful.
 }

 // first argument: name of the window
 // second argument: flag- types: 
 // WINDOW_NORMAL If this is set, the user can 
 // resize the window.
 // WINDOW_AUTOSIZE If this is set, the window size
 // is automatically adjusted to fit 
 // the displayed image, and you cannot
 // change the window size manually.
 // WINDOW_OPENGL If this is set, the window will be
 // created with OpenGL support.
 namedWindow("A_good_name", CV_WINDOW_AUTOSIZE);

 // first argument: name of the window
 // second argument: image to be shown(Mat object)
 imshow("A_good_name", img);
 
 waitKey(0); //wait infinite time for a keypress

 // destroy the window with the name, "MyWindow"
 destroyWindow("A_good_name"); 

 return 0;
}
// END OF PROGRAM

  Previous Post: https://www.geeksforgeeks.org/cpp/opencv-c-program-to-blur-an-image/ About the Author: 

Aditya Prakash is an undergraduate student at Indian Institute 👁 Aditya
of Information Technology, Vadodara. He primarily codes in C++. The motto for him is: So far so good. He plays cricket, watches superhero movies, football and is a big fan of answering questions.

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