Lossless Audio Steganography based on Lifting Wavelet Transform and Dynamic Stego Key

This paper presents a new lossless audio steganography approach based on Integer-to-Integer Lifting Wavelet Transform (Int2Int LWT) and Least Significant Bits (LSBs) substitution. In order to increase the security level a simple encryption with adaptive key has been proposed. The experimental results show that this approach has excellent transparency (above 45 dB of signal to noise ratio) with fixed high embedding capacity (25% from the audio cover signal size) and full recovery for the hidden secret message. Furthermore, robustness tests show immunity of the method against additive noise and perceptual statistical analysis. The proposed hiding and recovery procedures are simple and symmetry; therefore it can be easily used for real-time covert communication.