In “Sophisticated Image Encryption Using OpenCV,” Ashish Pant , Arjun Arora, Suneet Kumar , and Prof. R P Arora at the Dehradun Institute of Technology in Dehradun, India, describe a method by which an image transferred over the internet can be encrypted so that the hackers can not extract the useful information from the image.
By using open source computer vision library (OpenCV for short), the data structure of IPL Image (IPL is the main data type of OpenCV which represents image) and its member variable are analyzed and the basic library functions for image handling and processing are used.
Library functions are used for loading image, creating a window, saving image, creating an image and to access pixels of image in spatial domain. Arnold transformation also called cat-face transformation is used for first transforming the coordinates of the pixels which is called location scrambling.
After that multi dimensional Arnold transformation is used for color scrambling i.e. changing the pixel values for the Red, Green and Blue channels of the image, hence encrypting the image. Inverse Arnold transformation is used for decrypting the image and restoring original image.