Dynamic copy protection of optical media
View Patent ↗A method for copy protection includes receiving data in a recording module representing content to be recorded on a recording medium, the data including an indication that the content is to be protected from unauthorized copying. Responsive to the indication, the recording module signals a protection module to initiate a protection protocol in synchronization with the recording module. The protection module generates control information, so as to prevent the unauthorized copying of the content that is to be protected, and conveys the control information to the recording module, in accordance with the protocol. The recording module combines the control information with the data representing the content in the recording module, for recording on the recording medium.
1. A method for copy protection of a recording medium, the method comprising:
receiving data in a recording module representing content to be recorded on the recording medium, the data including an indication that the content is to be protected from unauthorized copying;
responsive to the indication, signaling a protection module to initiate a protection protocol in synchronization with the recording module;
conveying to the protection module sub-code channel information containing Program Memory Area (PMA) data for skipping at least part of a track of protected content on playback;
generating control information using the sub-code channel information by the protection module so as to cause an unauthorized readout device to skip the at least part of a track of protected content during playback, to prevent the unauthorized copying of the content that is to be protected;
conveying the control information from the protection module to the recording module, in accordance with the protocol;
combining the control information with the data representing the content in the recording module; and
recording the data combined with the control information on the recording medium.
2. A method according to claim 1 , wherein generating the control information comprises generating the control information responsive to the sub-code channel information, substantially without receiving the data representing the content at the protection module.
3. A method according to claim 1 , wherein signaling the protection module comprises sending a synchronization signal from the recording module to the protection module, and wherein conveying the control information comprises generating the control information in synchronization with the data, responsive to the synchronization signal.
4. A method according to claim 1 , wherein signaling the protection module comprises authenticating the protection module before proceeding with the protection protocol.
5. A method according to claim 1 , wherein generating the control information comprises preparing the control information so as to cause the recording module, upon combining the control information with the data, to effect logical changes in a sub-code channel associated with the data.
6. A method according to claim 1 , wherein generating the control information comprises preparing the control information so as to cause the recording module, upon combining the control information with the data, to modify the data so that at least a portion of the data will be identified as erroneous with respect to an error correcting code associated therewith.
7. A method according to claim 1 , wherein the recording medium comprises a compact disk (CD).
8. Apparatus for copy protection of a recording medium, the apparatus comprising:
a protection module, adapted:
to receive sub-code channel information containing Program Memory Area (PMA) data for skipping at least part of a track of protected content on playback,
to generate control information by using the sub-code channel information so as to cause an unauthorized readout device to skip the at least part of a track of protected content during playback to prevent unauthorized copying of protected content, and
a recording module, adapted:
to receive data representing the content to be recorded on the recording medium, the data including an indication that the content is to be protected from the unauthorized copying,
responsively to the indication, to signal the protection module to initiate a protection protocol in synchronization with the recording module,
to conveys the control information from the protection module to the recording module, in accordance with the protocol,
to receives the control information generated by the protection, module, and
to combines the control information with the data representing the content, so as to record the data combined with the control information on the recording medium.
9. Apparatus according to claim 8 , wherein the protection module is adapted to generate the control information responsive to the sub-code channel information, substantially without receiving the data representing the content.
10. Apparatus according to claim 8 , wherein the recording module is adapted to send the protection module a synchronization signal, and wherein the protection module is adapted to generate the control information in synchronization with the data, responsive to the synchronization signal.
11. Apparatus according to claim 8 , wherein the recording module is adapted to authenticate the protection module before proceeding with the protection protocol.
12. Apparatus according to claim 8 , wherein the protection module is adapted to prepare the control information so as to cause the recording module, upon combining the control information with the data, to effect logical changes in a sub-code channel associated with the data.
13. Apparatus according to claim 8 , wherein the protection module is adapted to prepare the control information so as to cause the recording module, upon combining the control information with the data, to modify the data so that at least a portion of the data will be identified as erroneous with respect to an error correcting code associated therewith.
14. Apparatus according to claim 8 , wherein the recording medium comprises a compact disk (CD).
15. Apparatus according to claim 8 , wherein the apparatus comprises a programmable processing unit, and wherein the recording and protection modules are implemented as processes running on the processing unit.
16. A computer software product comprising a computer-readable medium in which program instructions are stored, which instructions, when read by a computer, cause the computer to run a protection process and a recording process for recording protected content on a recording medium, wherein:
the protection process:
receives sub-code channel information containing Program Memory Area (PMA) data for skipping at least part of a track of protected content on playback, and
generates control information by using the sub-code channel information so as to cause an unauthorized readout device to skip the at least part of a track of protected content during playback, to prevent unauthorized copying of protected content,
and wherein:
the recording process:
receives data representing the content to be recorded on the recording medium, the data including an indication that the content is to be protected from the unauthorized copying,
signals the protection process to initiate a protection protocol in synchronization with the recording process, conveys the control information from the protection process to the recording process in accordance with the protocol,
receives the control information generated by the protection process,
combines the control information with the data representing the content, and
records the data representing the content combined with the control information on the recording medium.
17. A product according to claim 16 , wherein the instructions cause the protection process to generate the control information responsive to the sub-code channel information, substantially without receiving the data representing the content.
18. A product according to claim 16 , wherein the instructions cause the recording process to send the protection process a synchronization signal, and cause the protection process to generate the control information in synchronization with the data, responsive to the synchronization signal.
19. A product according to claim 16 , wherein the instructions cause the recording process to authenticate the protection process before proceeding with the protection protocol.
20. A product according to claim 16 , wherein the instructions cause the protection process to prepare the control information so as to cause the recording process, upon combining the control information with the data, to effect logical changes in a sub-code channel associated with the data.
21. A product according to claim 16 , wherein the instructions cause the protection process to prepare the control information so as to cause the recording process, upon combining the control information with the data, to modify the data so that at least a portion of the data will be identified as erroneous with respect to an error correcting code associated therewith.
22. A product according to claim 16 , wherein the recording medium comprises a compact disk (CD).