[OpenCV Tutorial] $1 - Load and Display an Image

Goal

In this tutorial you will learn how to:

• Load an image (using cv::imread )
• Create a named OpenCV window (using cv::namedWindow )
• Display an image in an OpenCV window (using cv::imshow )

Source Code

Download the source code from here.

#include <opencv2/highgui.hpp>

#include <iostream>

#include <string>

using namespace cv;

using namespace std;

int main( int argc, char** argv )

{

String imageName( "HappyFish.jpg" ); // by default

if( argc > 1)

{

imageName = argv[1];

}

Mat image;

image = imread( imageName, IMREAD_COLOR ); // Read the file

if( image.empty() ) // Check for invalid input

{

cout << "Could not open or find the image" << std::endl ;

return -1;

}

namedWindow( "Display window", WINDOW_AUTOSIZE ); // Create a window for display.

imshow( "Display window", image ); // Show our image inside it.

waitKey(0); // Wait for a keystroke in the window

return 0;

}