An optimized dynamically-random chaos based cryptosystem for secure images
Faiq Gmira, Said Hraoui, Abderrahim Saaidi, Jarrar Oulidi Abderrahmane, Khalid Satori · Applied Mathematical Sciences · 2014
In this paper, after reviewing the main point of image encryption, we investigated a new approach, presented in a dynamically-random scheme of digital image encryption, typically based on the simultaneous use of multiple discrete chaotic systems. In every tryout and after splitting the plain-image into several sub-blocks, each sub-block is encrypted differently from its adjacent by a discrete chaotic system issued at a random-draw from a Data Base of Chaotic Maps (DBCM) carefully chosen. Both the DBCM cardinality and the used maps number are determined by solving a combinatorial optimization problem with constraints. The encryption/decryption process is administered by two Codebooks that define the chaotic maps choice and regulate the encryption manner of the plain-image sub-block. Sub-blocks coordinates and Codebooks are supplementary secret parameters. The suggested scheme improves and strengthens the key space, robustness and security of images against statistical and brutal attacks. The security analysis of this scheme is widely evaluated. Therefore, the robustness is proved and justified.