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Tutorials MySQL & C, C++ Producing negative of a grayscale image: C++ and OpenCV - tutorial advance
Tutorials MySQL & C, C++ Producing negative of a grayscale image: C++ and OpenCV - tutorial advance
Producing negative of a grayscale image: C++ and OpenCV
destination source:https://www.programming-techniques.com/2013/01/producing-nagative-of-grayscale-image-c.html
Theory
The concept behind negative of grayscale image is very simple. Just subtract each intensity level of an image from 255. The negative transformation is given by the function
s = L – 1 – r
Where s is the pixel after transformation, r is the pixel before transformation and L is the maximum intensity level (in our case it is 256).
Program
The program is written in C++ using OpenCV library in QT IDE. If you are using QT IDE then add the following line of code in .pro file.
INCLUDEPATH += /usr/include/opencv/
CONFIG += link_pkgconfig
PKGCONFIG += opencv
LIBS += -Icv -Ihighhui
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 | #include <opencv/cv.h> #include <opencv2/core/core.hpp> #include <opencv2/highgui/highgui.hpp> using namespace cv; int main() { //read the image in matrix image Mat image = imread("charlie.jpg"); // initialize the output matrix with zeros Mat new_image = Mat::zeros( image.size(), image.type() ); // create a matrix with all elements equal to 255 for subtraction Mat sub_mat = Mat::ones(image.size(), image.type())*255; //subtract the original matrix by sub_mat to give the negative output new_image subtract(sub_mat, image, new_image); // Create Windows namedWindow("Original Image", 1); namedWindow("New Image", 1); // Show stuff imshow("Original Image", image); imshow("New Image", new_image); // Wait until user press some key waitKey(); return 0; } |
Output
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destination source:https://www.programming-techniques.com/2013/01/producing-nagative-of-grayscale-image-c.html
