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Steganalysis of Reversible Contrast Mapping Watermarking

This letter proposes a steganalysis scheme for detecting reversible contrast mapping (RCM) watermarking. RCM watermarking involves the transformation of pixel pairs belonging to the RCM domain, which introduces artifacts into the least-significant bit (LSB). We found that the LSB histogram varies between a stego-image to the cover image, and we used this information to design a specific steganalysis method for detecting RCM watermarking and also estimating the length of the hidden message. The experimental results show that the proposed scheme successfully breaks RCM watermarking for various embedding rates and can also accurately estimate the message length.