Patent ID: 7356142

Claim:
A method for receiving, decoding and presenting data recorded on a compact disk according to a proprietary format wherein the proprietary format is a variant of a standard compact disk format, such that a compact disk player compliant with the proprietary format plays compact disks compliant with the proprietary format but does not play compact disks compliant with the standard formats and compact disks compliant with the proprietary format cannot be successfully copied by a compact disk player compliant with the standard or proprietary formats, and the compact disks compliant with the proprietary format cannot be played on a compact disk player compliant with the standard format, the method comprising: receiving a plurality of channel frames of data from the compact disk at an EFM decoder; decoding the channel frames using EFM decoding to generate F3 frames; locating Q sub-channel bits in respective control bytes of the F3 frames; selectively inverting the Q sub-channel bits to generate decoded Q sub-channel information that after the inverting does not conform to the proprietary format and does conform to the standard format; and decoding and presenting the F3 frames using the decoded Q sub-channel information.