@article {18213,
	title = {Fingerprinting Compressed Multimedia Signals},
	journal = {Information Forensics and Security, IEEE Transactions on},
	volume = {4},
	year = {2009},
	month = {2009/09//},
	pages = {330 - 345},
	abstract = {Digital fingerprinting is a technique to deter unauthorized redistribution of multimedia content by embedding a unique identifying signal in each legally distributed copy. The embedded fingerprint can later be extracted and used to trace the originator of an unauthorized copy. A group of users may collude and attempt to create a version of the content that cannot be traced back to any of them. As multimedia data is commonly stored in compressed form, this paper addresses the problem of fingerprinting compressed signals. Analysis is carried out to show that due to the quantized nature of the host signal and the embedded fingerprint, directly extending traditional fingerprinting techniques for uncompressed signals to the compressed case leads to low collusion resistance. To overcome this problem and improve the collusion resistance, a new technique for fingerprinting compressed signals called Anti-Collusion Dither (ACD) is proposed, whereby a random dither signal is added to the compressed host before embedding so as to make the effective host signal appear more continuous. The proposed technique is shown to reduce the accuracy with which attackers can estimate the host signal, and from an information theoretic perspective, the proposed ACD technique increases the maximum number of users that can be supported by the fingerprinting system under a given attack. Both analytical and experimental studies confirm that the proposed technique increases the probability of identifying a guilty user and can approximately quadruple the collusion resistance compared to conventional Gaussian fingerprinting.},
	keywords = {coding;, coding;copy, collusion;digital, communication;video, compression;digital, compression;video, dither;collusion, domain, fingerprinting;anti-collusion, fingerprinting;multimedia, Gaussian, management;multimedia, protection;data, resistance;compressed, rights},
	isbn = {1556-6013},
	doi = {10.1109/TIFS.2009.2025860},
	author = {Varna,A.L. and He,Shan and Swaminathan,A. and M. Wu}
}
@conference {18178,
	title = {Collusion-Resistant Fingerprinting for Compressed Multimedia Signals},
	booktitle = {Acoustics, Speech and Signal Processing, 2007. ICASSP 2007. IEEE International Conference on},
	volume = {2},
	year = {2007},
	month = {2007/04//},
	pages = {II-165 -II-168 - II-165 -II-168},
	abstract = {Most existing collusion-resistant fingerprinting techniques are for fingerprinting uncompressed signals. In this paper, we first study the performance of the traditional Gaussian based spread spectrum sequences for fingerprinting compressed signals and show that the system can be easily defeated by averaging or taking the median of a few copies. To overcome the collusion problem for compressed multimedia host signals, we propose a technique called anti-collusion dithering to mimic an uncompressed signal. Results show higher probability of catching a colluder using the proposed scheme compared to using Gaussian based fingerprints.},
	keywords = {based, compression;Gaussian, compression;multimedia, dithering;collusion-resistant, fingerprinting;multimedia, Gaussian, processes;data, sequences;anticollusion, signals, spectrum, spread, systems;},
	doi = {10.1109/ICASSP.2007.366198},
	author = {Varna,A.L. and He,Shan and Swaminathan,A. and M. Wu and Lu,Haiming and Lu,Zengxiang}
}
