Countermeasures for Collusion Attacks Exploiting Host Signal Redundancy

Multimedia digital data is highly redundant: successive video frames are very similar in a movie clip, most songs contain some repetitive patterns, etc. This property can consequently be exploited to successively replace each part of the signal with a similar one taken from another location in the same signal or with a combination of similar parts. Such an approach is all the more pertinent when video content is considered since such signals exhibit both temporal and spatial selfsimilarities. To counter such attacking strategies, it is necessary to ensure that embedded watermarks are coherent with the redundancy of the host content. To this end, both motion-compensated watermarking and selfsimilarities inheritance will be surveyed.