| 摘要 |
Access to an audiovisual product such as DVD video is controlled by dividing the data into cells A,B,C1,D which are scrambled into at least first and second video streams 1901, 1902 and a video stream switch instruction 2011, 2021 automatically switches between them during reproduction so that the cells are reproduced at appropriate times. Multi-angle video objects 2020 hold the cells in a selected video stream 1902 while holding nil or erroneous data C2 in other streams 1901. Switch instructions 2011, 2021 may be created from a hidden menu button command. Sequences may be generated using iterative algorithms and may comprise one correct sequence instruction (fig 4, 410a) that reproduces the sequence A,B,C and a plurality of incorrect sequence instructions (fig 4, 410b) each of which replays the sequence in the wrong order, e.g A,C,B; B,A,C etc. The structure location of the correct sequence (fig 4, 410a) may be derived from an access code or password. |
