Abstract: Image steganography transfers message secretly by embedding the message into a cover image to implement covert communication. We presented an image steganographic algorithm called VSQS. A secret key dependent Uaussian sequence was generated and then rounded, which is used for the step-varying quanti}ation of the pseudo-random permuted image pixels. Depending on the relationship between the ctuantized pixels and the secret message, the image pixels were modified to embed the message. Furthermore, an extension of this algorithm(called TLQS) was presented. Experimental results show that both the VSQS and TLQS image steganographic techniques may provide higher capacity and be resistant to several well-known steganalytic methods.

Key words: Steganography, Gaussian scqucnce, Quantization, Steganalysis