Very Fast Watermarking by Reversible Contrast Mapping

• Published in: IEEE signal processing letters Vol. 14; no. 4; pp. 255 - 258
• Main Authors: Coltuc, D., Chassery, J.-M.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2007; The Institute of Electrical and Electronics Engineers, Inc. (IEEE); Institute of Electrical and Electronics Engineers
• Subjects: Complexity; Computer Science; Computer Vision and Pattern Recognition; Costs; Data compression; Data encapsulation; Difference expansion; embedding bit-rate; Equations; Histograms; Information Theory; Mapping; Mathematical analysis; Mathematics; Multimedia; Pixel; Pixels; RCM; reversible contrast mapping (RCM); reversible watermarking; Robustness; Table lookup; Transforms; Watermarking
• ISSN: 1070-9908; 1558-2361
• DOI: 10.1109/LSP.2006.884895

Reversible contrast mapping (RCM) is a simple integer transform that applies to pairs of pixels. For some pairs of pixels, RCM is invertible, even if the least significant bits (LSBs) of the transformed pixels are lost. The data space occupied by the LSBs is suitable for data hiding. The embedded information bit-rates of the proposed spatial domain reversible watermarking scheme are close to the highest bit-rates reported so far. The scheme does not need additional data compression, and, in terms of mathematical complexity, it appears to be the lowest complexity one proposed up to now. A very fast lookup table implementation is proposed. Robustness against cropping can be ensured as well