Embedding fingerprinting or watermarking information includes delivering
information in-band within digital content representing a media stream, so unauthorized
distributors must choose between degrading the media stream, or leaving sufficient
information detectable that unauthorized distribution can be detected. For fingerprinting,
the method provides a relatively high degree of confidence of both detecting at
least one colluding unauthorized distributor, and not falsely accusing any innocent
party of being an unauthorized distributor. Embedding fingerprinting or watermarking
information includes selecting a sequence of locations within digital content,
and embedding information in the form of a sequence of one or more bits at each
of those locations, thus representing a set of marking symbols. Marking symbols
cannot be readily manufactured without at least one colluding unauthorized distributor
having received it, so any distributed digital content includes at least some marking
symbols traceable to at least one colluding unauthorized distributor.