Abstract: LSB matching steganographic method has the advantage of large capacity and high invisibility, but the histogram of the stego image produced by this method is smoothened. Then attackers can detect whether the image has been changed. In this paper, an improved method was proposed. According to the complementary property of the random士1 behavior, the improved method embeds most of the secrete bits in pixels with adjacent intensity. By the proposed method the cover image's histogram can be maintained in a considerable extend so as to make the stego image more difficult to be detected than I_SI3 matching steganograpy.

Key words: LSB matching, Histogram, Statistic analyzer