• Biji Babu
• Annie George

With the developments of communication technolo- gies, sensitive media are processed and delivered in digital format. Most cases this media is imperative and must be maintained from any unauthorized attacks. The security of digital images is very essential for many multimedia applications including military images, medical images systems, wireless networks, and portable devices. To preserve the secretness of the transmitted images, different encryption techniques are employed. In this direction, the chaotic based ciphers have shown brilliant performance. Recently, permutation-diffusion based multimedia encryption techniques have been developed. In traditional architecture, permutation and diffusion functions are applied in two separate phases. This separable design helps the attacker to launch several attacks and also causes to the degradation of the encryption speed. To avoid these problems, in this work, we propose a simultaneous permutation and diffusion-based efficient image cryptosystem which combines pixel scrambling and shuffling using Arnold Cat map, in which the image pixels are processed in a dynamic order fashion. Simulation results, histogram analysis, and key sensitivity analysis proved that the image cipher has several brilliant features and a good performance against various types of attacks. Thus, the cryptosystem is strongly appropriate for practical image security applications.

Encryption, Cipher, Permutation, Diffusion, Arnold Cat map.

"Simultaneous Permutation and Diffusion Based Efficient Chaotic Image Cryptosystem", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 5, page no.218-223, May 2019, Available :http://www.jetir.org/papers/JETIRCV06043.pdf

"Simultaneous Permutation and Diffusion Based Efficient Chaotic Image Cryptosystem", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 5, page no. pp218-223, May 2019, Available at : http://www.jetir.org/papers/JETIRCV06043.pdf