Concealment of Speech Signals within Speech by Combining Cryptography and Steganography
Jalil Shirazi · Transactions on Machine Intelligence · 2021
The concealment of speech signals, particularly within other speech signals, encompasses the integration of cryptographic techniques and steganographic methods. This literature review synthesizes current research findings and identifies existing gaps in knowledge, while also suggesting potential future research directions. In this paper, to enhance data security in speech transmission, a combination of steganography and cryptography is utilized. In the encryption phase, the Discrete Cosine Transform (DCT) is applied to frames of the speech signal. This phase involves scrambling time-domain samples, transform coefficients, and time-domain samples obtained from the inverse transform of the signal using a chaotic function that generates random numbers. In the steganography phase, the encrypted data replaces the low-value coefficients of the Discrete Wavelet Transform (DWT) of the host speech signal. To evaluate the proposed hybrid method, both qualitative and quantitative metrics were used. The results indicate a high level of various metric measures for the method.