Primitive Roots and Euler Totient Function-Based Progressive Visual Cryptography

Visual cryptography is a branch of cryptography that focuses on the encryption and decryption of images or visual data. The main objective of this paper is to introduce a visual cryptography scheme based on primitive root modulo 251 for encryption of a grayscale image, making it visually incomprehensible to unauthorized users. The mapping algorithm generated enhances security and efficiency of original image and subsequently shares are generated using bit-plane slicing. The generated shares possess high quality, ensuring accurate reconstruction of the original image. Moreover, for Inverse Mapping we took discrete logarithms and recovered image with no major contrast loss.