Speech Encryption Based on 5D Hyperchaotic System for AMR-WB Codec
Messaouda Boumaraf, Fatiha Merazka · 2019
In this paper, we propose an hyperchaos-based speech encryption algorithm for AMR-WB Codec. The algorithm adopts a 5D hyperchaotic system, and the generated key stream is employed for confusion and diffusion processes. In order to strengthen the security of the cryptosystem, a chaotic shift keying mechanism is employed and keys are assigned for confusion and diffusion processes. Whereas the keys xnare employed for the confusion of the frame's parameters using permutation, the keys yn, zn, wnand unare used for diffusion that is performed by the Xor operation with the parameters of the 4 codec's sub-frames. Simulation and statistical analysis through the Enhanced Modified Bark Spectral Distortion (EMBSD) and Mean Opinion Score (MOS) prove that this approach works well and confirm the efficiency of our presented schemes.