Optical audio signal hiding algorithm based on fractional Fourier transform domain and Gerchberg Saxton phase recovery

This article proposes an audio signal encryption method based on the Gerchberg-Saxton (G-S) phase recovery algorithm in the fractional Fourier transform domain. The algorithm first encodes the original audio signal into an image format and encrypts it. Subsequently, the G-S phase recovery algorithm is used in the fractional Fourier domain to extract the phase information of the audio signal. On this basis, the original audio phase is replaced with a reference phase representing the secret information to achieve information embedding. This technology can select two different types of keys according to encryption requirements, further increasing the difficulty of decryption and ensuring information security. Ultimately, the encrypted image can be decrypted and restored to the original audio signal. This scheme achieves effective embedding and extraction of secret information in audio signals through the replacement and recovery of phase information.