The design and implementation of a prototype digital video watermarking scheme with dynamic traitor tracing

[摘要] ENGLISH ABSTRACT: We design and implement a prototype digital watermarking scheme that usesspread-transform dither modulation to embed hidden binary message signalsinto uncompressed digital video signals. The hidden messages are intendedto identify the original recipient of a particular copy of a digital video, sothat in the event that a pirate copy of that video is found, the recipient can beincriminated as a pirate. We test the ability of the watermark signal to survivevarious modifications to the watermarked video, including lossy compression,frame deletion, and amplitude scaling. We find that the scheme performswell when watermarked videos remain uncompressed, but the scheme is notsufficiently robust against lossy compression. We also implement a dynamictraitor tracing scheme based on the scheme of Fiat and Tassa, which is designedto identify a group of pirates who combine their watermarked videos in anattempt to defeat the watermarking scheme. We test the traitor tracing schemein a simulated digitally watermarked video broadcast system where a piraterebroadcast is monitored. We find that when the pirate rebroadcast is delayed,our traitor tracing scheme identifies and disconnects the pirates more quicklythan the scheme of Fiat and Tassa.

[发布机构] Stellenbosch University