US 2010/0177613 A1 · Access Controlled Optical Disc and Method Therefor

Abstract

An optical disc is disclosed having a set of primary tracks and a set of alternate tracks. At least some of the primary and alternate tracks are associated. When a CD-DA reader accesses the optical disc, it locates only the primary tracks. By contrast, when a data reader such as a CD-Rom drive accesses the disc, modifications to the Table of Contents (TOC) cause the data reader not to access a given primary track but instead to be directed to its associated alternate track. This alternate track may contain audio (CD-DA) data which may or may not correspond with the CD-DA data in the associated primary track. The alternate tracks may be copy protected, and/or may include compressed (not CD-DA) data which is the subject of digital rights management.

Claims40

Dependent claims

An optical disc comprising:

a session having a main data channel and a plurality of sub-code channels, the session including at least one primary track and at least one alternate track each formed within the main data channel;
and
disc data access information, stored upon the optical disc, and which is read and utilized only by an optical disc data reader, the disc data access information being such as to prevent location of the, or at least one of the, primary track(s), when the optical disc is read by the optical disc data reader, and to direct the optical disc data reader instead to the, or an associated, alternate track.

A method of generating data for writing onto a session of an optical disc, the session having a main data channel and a plurality of sub-code channels, the method comprising:

generating primary data representative of m primary track(s) for the optical disc (m≧1), for writing to the main data channel of the session;
generating alternate data representative of n alternate track(s) for the optical disc (n≧1), for writing to the main data channel of the session;
and
assembling a table of contents (TOC) for the optical disc, the TOC containing disc access control information which, when written to an optical disc, indicates to an optical disc data reader that there are m tracks in total written upon that optical disc.

1 more element

Dependencies are inferred from the claim text.

Facts

Application

12/719,149Filed 8 Mar 2010

Priority

GB 0216142.011 Jul 2002

Published

15 Jul 2010

Term ends

Not estimatedThe source records don’t support an estimate.

Classification14 codes

G11B 20/00826
Wherein the usage restriction limits the signal quality, e.g. by low-pass filtering of audio signals or by reducing the resolution of video…
G11B 19/04
Control of operating function, e.g. switching from recording to reproducing: arrangements for preventing, inhibiting, or warning against double…
G11B 19/122
By sensing distinguishing features of or on records, e.g. diameter end mark: involving the detection of an identification or authentication mark
G11B 20/00086
Signal processing not specific to the method of recording or reproducing; Circuits therefor: circuits for prevention of unauthorised reproduction…

Access Controlled Optical Disc and Method Therefor

Life of this patent

Access Controlled Optical Disc and Method Therefor

Life of this patent

Abstract

Claims40