Audio Signal Encryption Based on Permutation Relations and Residue Number System

This paper presents a new audio encryption algorithm based on permutation and residue number system. In the current approach, signal samples are combined with residue number system through permutation; therefore, a specific noise is generated. Then, the audio signal is combined with the noise, generated by the algorithm, to produce a silence signal. For this purpose, the algorithm uses a predefined permutation format and a modular set in the form of {2n-1, 2n, 2n+1} to encrypt the main signal. Consequently, the proposed algorithm converts the input signal into a silence signal and increases its security. The signal-to-noise ratio (SNR) was used to evaluate the algorithm. The results indicated very low values of SNR pertaining to audio signals in the proposed method.