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Lossless data hiding: fundamentals, algorithms and applications

Recently, among various data hiding techniques, a new subset called lossless data hiding has drawn tremendous interest. By lossless data hiding, it is meant that the marked media can be reversed to the original cover media without any distortion after the hidden data are retrieved. After a careful study of all lossless data hiding algorithms published up to today, we classify the existing algorithms into three categories: 1) Those developed for fragile authentication; 2) Those developed aiming at large embedding capacity; 3) Those developed for semi-fragile authentication. The mechanisms, merits, drawbacks and applications of these algorithms are analyzed, and some future research issues are addressed in this paper.