An enhanced variable-length arithmetic coding and encryption scheme using chaotic maps

We enhance the simultaneous arithmetic coding and encryption scheme previously proposed by us. By encoding a block of variable number of symbols to a codeword within the length of the computation register, the operating efficiency has been substantially improved. Moreover, the compressed sequence is processed by an additional diffusion operation which strengthens the security of the original scheme by having higher key and plaintext sensitivities. Simulation results show that the enhanced scheme runs faster than the original scheme and the traditional compress-then-encrypt approach at a comparable compression performance. (c) 2013 Elsevier Inc. All rights reserved.