A security steganography method for lossy compression gray scale image

Abstract

Based on DCT coefficients, we propose a steganographic technique. Our method embeds a message into the DCT coefficients of an image according to the relative size of a selected DCT coefficient value and the average value of its adjacent coefficients in the block to embed and extract the hiding message bit. The coefficients are chosen middle-to-low frequency coefficients in order to defend against JPEG compression. The method decreases the likelihood of being detected, and the resulted stego-image can be stored in JPEG format. The hidden message can be securely transformed. Our experiments show that our method can extract the data efficiently and blindness. © Springer-Verlag Berlin Heidelberg 2007.