Invert Images and Videos

Here is the original image which I am going to filter using above methods.

Inverting an image is like taking the negative of an image.


#include "stdafx.h"
#include <cv.h>
#include <highgui.h>

int main()
        //display the original image
        IplImage* img = cvLoadImage("C:/MyPic.jpg");
        cvShowImage("MyWindow", img);

        //invert and display the inverted image
        cvNot(img, img);
        cvShowImage("Inverted", img);

        //cleaning up
        return 0;


You can download this OpenCV visual c++ project from here

Inverted Image

 New OpenCV functions which are not found earlier are explained here
  • cvNot(img, img)
This function inverts every bit in every element of the image in the 1st parameter and places the result in the image in the 2nd parameter.
This function can process images in place. That means same variable can be used for the 1st and 2nd parameters.

e.g - For a 8 bit image, the value 0 will be mapped to (255-0)=255
                                        the value 46 will be mapped to (255-46)=209

        For a 16 bit image, the value 0 will be mapped to (65535-0)=65535
                                   the value 46 will be mapped to (65535-46)=65489