Method for making copy protected optical discs
AssigneeDenon Digital LLC
InventorBen Garcia
Life of this patent
Estimating the term…
Abstract
A machine-non-readable defect is formed on a CD-ROM by re-modulation of a master cutting laser beam recorder. Re-modulation in specific program areas creates non-readable marks which interfere with any attempt to image-copy the CD-ROM. The non-machine-readable marks can be followed by valid data which may be used as keys to verify the authenticity of the CD-ROM. The machine-non-readable defect is invisible to the human eye to thwart detection and subsequent reverse engineering attempts.
Claims17
A method for protecting against unauthorized copying of information on an optical medium comprising the steps of:
- a) placing at least one mark at each of at least one corresponding predetermined location on an optical medium, which at least one location is within a continuous spiral track of said optical medium, which mark is incapable of being reproduced except by a mass reproduction recorder, and which mark, when read by a device adapted to read data contained in said continuous spiral track is incapable of being read, and, thereby prevents writing a copy of said mark on an optically recordable medium;
- b) adding an executable code module to said optical medium, said executable code module adapted to verify said at least one mark, and allow access to data and programs on said optical medium after said verification of said at least one mark.
A method for protecting against unauthorized copying of information on an optical medium comprising the steps of:
- a) placing at least one mark at each of at least one corresponding predetermined location on an optical medium, which at least one location is within a continuous spiral track of said optical medium, which mark is incapable of being reproduced except by a mass reproduction recorder, and which mark, when read by a device adapted to read data contained in said continuous spiral track is incapable of being read, and, thereby prevents reading and of data following said mark and subsequent writing of said unread data on an optically recordable medium;
- b) adding an executable code module to said optical medium, said executable code module adapted to verify correctness of data following said mark contained on said optical medium.
Dependencies are inferred from the claim text.