Highly transparent steganography model of speech signals using Efficient Wavelet Masking

► We design a steganography model of speech-in-speech signals. ► The model, Efficient Wavelet Masking, is based on the masking property of the HAS. ► The core is the efficient sorting of the wavelet coefficients of the secret message. ► EWM and other methods such as LSB, FM, SS, SSA, have been analyzed. ► Statistical transparency is better in EWM than in LSB, FM, SS and SSA.