A Reversible Steganography Suitable for Embedding Small Amounts of Data

A reversible information hiding scheme that is suitable for embedding small amounts of data is proposed in this paper. The secret data are transformed to basek data stream, and each number is embedded into a pixel pair if the pixels’ difference is within a certain range. Referring a pre-determined table, the gray values of the pixel pair are modified so as to carry the secret number. In order to distinguish the secret-carry pairs from no-secret-carry pairs, the differences of the pixel pairs without secret data embedded are expanded by modification of the difference histogram. The proposed information hiding scheme has flexible embedding capacity and low overhead. The peak signal-to-noise ratio (PSNR) is greater than those of existing methods that are based on histogram modification when the embedding capacity is low. Experimental results showed that the proposed scheme provides good embedding performances for small amounts of embedded data.