Abstract: The practice of concealing a file, message, image, audio or any other media in another file, image, audio or video in such a way that only the sender and receiver know about the message being transmitted is called steganography. In this paper, first an enhancement is proposed to the work of Sanmitra Ijeri et al. wherein a hard sudoku is used instead of a soft sudoku. The embedding and extraction algorithms are generalized to work with any NxN sudoku where N is a perfect square. A comparison is then made between the hard and soft sudoku techniques. A study is also performed to compare parameters such as PSNR and payload capacity for different sudoku sizes.
Keywords: Image steganography, Cover Image, Stego Image, Hard Sudoku, Reference Matrix, Pixel, PSNR