Watermarking an audiovisual product by selecting and reproducing a sequence of watermark characters upon playback

摘要

An audiovisual product is recorded with a set of watermark characters, F1-F7, J1-J7, M1-M7, Y1-Y7, as video or audio objects, A-Z. A sequence of the watermark characters is selected and reproduced upon playback to uniquely identify a particular playback instance. Ideally, a user identity code is received upon playback amongst a predetermined set of user identity codes, and the sequence of watermark characters is selected and replayed according to the received user identity code. The sequence of watermark characters allows the user identity code to be traced should the audio and/or visual output of the audiovisual product be recorded such as with a video cassette recorder (VCR). Alternatively, a recorded navigational structure of the audiovisual product may be used to select and replay the sequence of watermark characters.