Abstract: The amount of digital data transmitted across the network has been increased due to the advancement in internet technologies. The exchange of sensitive and confidential multimedia data via internet necessitates a demand for secure transmission. The conventional encryption algorithms used to encrypt text data are not desirable to encrypt multimedia data. This study proposes a new image encryption method using scan pattern based pixel permutation and bitwise XOR operation using random key stream. The new scan pattern for pixel permutation is derived from the concept of rat-in-a-maze. The proposed random key stream to perform bitwise XOR operation is generated by adapting the randomized bit pattern generation method used for the SHA-512 hash function. The proposed method resists statistical, differential, ciphertext-only and known plaintext attacks. It has sufficient key space to resist exhaustive key search attack and attains optimal entropy value. The NIST randomness test assured that the proposed random key stream contains random bits for effective encryption.
T. Sivakuma and T. Anusha, 2016. A New Image Encryption Method Using Scan Pattern and Random Key Stream. Asian Journal of Information Technology, 15: 4635-4647.