| 摘要 |
Disclosed are techniques and systems for manufacturing an optical disc having a stochastic (i.e., non-deterministic) anti-piracy feature in the form of a multi-spiral structure, and for verifying the feature on the optical disc to authenticate the disc for playback. The multi-spiral structure may be comprised of multiple partially interleaved, and partially overlapping, spiral data tracks formed in a designated area of the optical disc. A process of forming the multi-spiral structure may include forming, in the designated area, a first spiral data track with first track pitch and a second spiral data track with second track pitch that is different than the first track pitch. The multi-spiral structure may be analyzed to determine verification parameters for verifying the multi-spiral structure, and those verification parameters may be encrypted so that they may be subsequently decrypted and used to verify the multi-spiral structure on a disc reading device. |
