The invention provides a method of forensic digital watermarking that
randomly selects an orientation and/or embedding protocol for a forensic
digital watermark signal to be embedded in the content signal. It then
embeds the forensic digital watermark signal at the selected orientation
in the content signal. The embedding applies a different orientation to
the digital forensic watermark for each instance of embedding a forensic
watermark. This thwarts averaging and over-embedding attacks and enables
generational forensic tracking.