@techreport{kirovski2001a, author = {Kirovski, Darko and Malvar, Henrique S. and Yacobi, Yacov}, title = {A Dual Watermarking and Fingerprinting System}, year = {2001}, month = {June}, abstract = {We present a new dual watermarking-fingerprinting (WM/FP) system, where initially all copies of a protected object are identically watermarked using a secret key, but individual detection keys are distinct. By knowing a detection key, an adversary cannot recreate the original content from the watermarked content. However, knowledge of any one detection key is sufficient for modifying the object so that a detector using that key would fail to detect the marks. Detectors using other detection keys would not be fooled, and such a modified object necessarily contains enough information about the broken detector key – the fingerprint. Our dual WM/FP system limits the scope of possible attacks, when compared to classic fingerprinting systems. Under optimal attacks, the size of the collusion necessary to remove the marks without leaving a detectable fingerprint is superlinear in object size, whereas classic fingerprinting has a lower bound on collusion resistance that is approximately fourth root in object size. By using our scheme one can achieve collusion resistance of up to 100,000 users for a two hour high-definition video.}, url = {http://approjects.co.za/?big=en-us/research/publication/a-dual-watermarking-and-fingerprinting-system/}, pages = {14}, number = {MSR-TR-2001-57}, }