[OpenCV Tutorial] $2 - Load, Modify, and Save an Image

Goals

In this tutorial you will learn how to:

• Load an image using cv::imread
• Transform an image from BGR to Grayscale format by using cv::cvtColor
• Save your transformed image in a file on disk (using cv::imwrite )

Code

Here it is:

#include <opencv2/opencv.hpp>

#include "string"

using namespace cv;

int main( int argc, char** argv )

{

String imageName = "Color_Image.jpg";

Mat image;

image = imread( imageName, 1 );

Mat gray_image;

cvtColor( image, gray_image, COLOR_BGR2GRAY );

imwrite( "Gray_Image.jpg", gray_image );

namedWindow( imageName, WINDOW_AUTOSIZE );

namedWindow( "Gray image", WINDOW_AUTOSIZE );

imshow( imageName, image );

imshow( "Gray image", gray_image );

waitKey(0);

return 0;

}