New secure and efficient substitution and permutation method for audio encryption algorithm.

A new substitution and permutation method for the encryption/decryption of two-channel audio files based on chaotic maps is presented. The proposed scheme's structure depends on encoding the original audio data into a new data range. Each value in the resulted range was translated to a binary sequence and both substitution and permutation operations are accomplished using the chaotic state and chaotic parameters. The substitution was attained using the XORing operation and Bernoulli substitution while the permutation method was based on the numbers sequence generated using a hyper chaotic system. A new key generation algorithm is proposed based on the properties of the square root of large prime numbers and a hyper chaotic system to produce the keys. The proposed cipher system was tested by various audio file sizes of (.WAV) extension. Performance evaluation and security measures to assess the algorithm's security against various attacks. The results of the key space analysis, statistical analysis, mean square error analyses, Peak signal to noise ratio (PSNR) analyses, entropy analyses, homogeneity, contrast, SNR, etc. showed that the proposed cipher is notably secured in opposition to the attackers and possesses an effective diffusion and confusion mechanism for better audio communication with inside the area of telecommunication. [ABSTRACT FROM AUTHOR]