Improving the embedding efficiency of weight matrix-based steganography for grayscale images

This paper firstly reviews a classical data hiding scheme based on weight matrix, and then indicates the possibility of improving the embedding efficiency and payload of it when it is applied to grayscale images. An improved steganographic scheme is subsequently proposed to not only accomplish the goal of improving the performance, but also remedy a security vulnerability of previous scheme in a special case of fully-embedding pattern by employing random permutation rather than binary matrix exclusive-or operation. Different from two-bit modification in Tseng's scheme, we use the pixel as the element of embedded block F-i, i.e. [F-i](j,k) is an element of [0,255]. We can add or subtract a given value to the SUM arbitrarily by modifying only one pixel, which guarantees the imperceptibility effectively. Additionally, the embedding efficiency and payload of proposed scheme will be both increasing at the same time. The experimental results also demonstrate that the proposed scheme is superior to the previous technique in terms of performance and security. (C) 2012 Elsevier Ltd. All rights reserved.