Abstract
This paper introduces an audio encryption algorithm based on permutation of audio samples using discrete modified Henon map followed by substitution operation with keystream generated from the modified Lorenz-Hyperchaotic system. In this work, the audio file is initially compressed by Fast Walsh Hadamard Transform (FWHT) for removing the residual intelligibility in the transform domain. The resulting file is then encrypted in two phases. In the first phase permutation operation is carried out using modified discrete Henon map to weaken the correlation between adjacent samples. In the second phase it utilizes modified-Lorenz hyperchaotic system for substitution operation to fill the silent periods within the speech conversation. Dynamic keystream generation mechanism is also introduced to enhance the correlation between plaintext and encrypted text. Various quality metrics analysis such as correlation, signal to noise ratio (SNR), differential attacks, spectral entropy, histogram analysis, keyspace and key sensitivity are carried out to evaluate the quality of the proposed algorithm. The simulation results and numerical analyses demonstrate that the proposed algorithm has excellent security performance and robust against various cryptographic attacks.
Highlights
Voice based communication becomes prominent in several areas such as military, phone banking, confidential voice conferencing, education etc
Single and multiple round of permutation--diffusion without substitution-box (PT-DWOS), deoxyribonucleic acid (DNA) encoding methods are introduced based on the reproducibility and deterministic nature of chaotic functions, since the process can be repeated for the same function and same initial conditions
Chaos theory have been incorporated in many conventional cryptographic approaches like S-box design [16], RC5 stream cipher [17] and elliptical curve cryptography [18] to strengthen the security of the encryption processes
Summary
Voice based communication becomes prominent in several areas such as military, phone banking, confidential voice conferencing, education etc. Mosa et al [24] introduced an algorithm based on permutation and substitution of speech segments using chaotic Baker map They used Discrete Cosine Transform (DCT) to remove the residual intelligibility in order to compress the signal. Halto et al [26] presented a hybrid chaotic speech encryption algorithm in which Arnold cat map is utilized for permutation and logistic map for substitution operation They used Discrete Cosine Transform (DCT) for compressing the audio signal to minimize residual intelligibility. Sheela et al [30] proposed an algorithm based on two-dimensional modified Henon map (2D-MHM) and standard map They introduced Hybrid Chaotic Shift Transform (HCST), and deoxyribonucleic acid (DNA) encoding rules to enhance the security level.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
