US Patent 7577272 Digital fingerprinting using synchronization marks and watermarks

Digital fingerprinting using synchronization marks and watermarks. At a watermark embedder, an input host signal is divided into regions, and a subset of the regions is selected to receive synchronization marks. Respective synchronization marks are then embedded into the selected regions. At a receiver, an input signal is divided into regions, and a subset of the regions is synchronized with additional regions, which were defined by the embedder when producing the signal that is input to the receiver. Also, the receiver can model any geometric distortion undergone by the input signal between the embedder and the receiver.