Correlation based highly secure image hiding in audio signals using wavelet decomposition and chaotic maps hopping for 5G multimedia communications

Audio Steganography is the technique of hiding any secret information behind a cover audio file without impairing its quality. Data hiding in audio signals has various applications such as secret communications and concealing data that may influence the security and safety of governments and personnel and has possible important applications in 5G communication systems. This paper proposes an efficient secure steganography scheme based on the high correlation between successive audio signals. This is similar to the case of differential pulse coding modulation technique (DPCM) where encoding uses the redundancy in sample values to encode the signals with lower bit rate. Discrete Wavelet Transform (DWT) of audio samples is used to store hidden data in the least important coefficients of Haar transform. We use the benefit of the small differences between successive samples generated from encoding of the cover audio signal wavelet coefficients to hide image data without making a remarkable change in the cover audio signal. instead of changing of actual audio samples so this doesn't perceptually degrade the audio signal and provides higher hiding capacity with lower distortion. To further increase the security of the image hiding process, the image to be hidden is divided into blocks and the bits of each block are XORed with a different random sequence of logistic maps using hopping technique. The performance of the proposed algorithm has been estimated extensively against attacks and experimental results show that the proposed method achieves good robustness and imperceptibility.