Efficient Audio Encryption Using a Discrete Cosine Transform and Baker Map

With the expansion and improvement of technology and communication in recent years, the necessity to secure and defend these communications from various threats has increased. In this research, we provide a novel method for encrypting audio signals utilizing Baker and discrete cosine transform (DCT) chaotic maps. Three typical audio samples of funky, muted trumpet, and flute are converted into 2D to enable the use of chaotic maps. Then, a DCT is used to extract the coefficients, and the Baker chaotic map is used to replace them. Finally, an inverse DCT is used to perform the encryption. The DCT is applied to the sample during the decryption stage, and the coefficients are altered using the Baker map. An inverse DCT is then applied, and the output is transformed from 2D to 1D to obtain the original audio signal. The effectiveness of the proposed coding model based on Baker maps and DCT is evaluated using a variety of measures, including entropy, histogram, correlation coefficient, spectrogram, noise effect, and differential tests, and the results demonstrate the effectiveness of the proposed encryption model.