A New Algorithm of Encryption and Decryption of Images Using Chaotic Mapping

In this paper a novel image encryption algorithm is proposed based on combination of pixel shuffling and three chaotic maps. This algorithm is based on pixel scrambling where in the randomness of the chaos is utilized to scramble the position of the data. Shuffling is used to expand diffusion in the image and dissipate the high correlation among image pixels. Due to sensitivity to initial conditions, chaotic maps have a good potential for designing dynamic permutation map. In the proposed algorithm, the plainimage is first decomposed into 8x8 size blocks and then the block based shuffling of image is carried out. After that the shuffled image is encrypted using chaotic sequence generated by one another chaotic map. In order to evaluate performance, the proposed algorithm was measured through a series of tests. Experimental results illustrate that the scheme is highly key sensitive and shows a good resistance against brute-force and statistical attacks. Keywords—Image encryption, chaotic maps, image shuffling, logistic map, transposition technique.