Device for copy protection
First Claim
1. Device for copy protection of data media units (10) carrying digital documents, especially of optically readable data media, with means for applying a digital content (2) of the digital document onto the data media unit in a physical or logical structure associated with the data media unit and means for applying additional code (3) onto the data media unit by predetermined change of the physical structure, so that during a regulated playback and/or display process of the digital data media unit by a regulation playback and/or display unit (15) the additional code is not captured and has no influence on the originating or displayed digital content of the digital document, characterized by verification means being provided for recognition of a legally produced specimen of the data media unit, which, by bypassing possible error correction or filtering units in the playback or display unit provided for a data media unit, enable immediate reader access to the additional code and makes it possible to determine, if the additional code is present and if it corresponds to the additional code applied by the application means.
1 Assignment
0 Petitions
Accused Products
Abstract
The invention concerns a device for copy protection of especially optical data media such as CD/DVD. By applying additional code within the redundancy area of the logical and/or physical data media format, the data media unit receives additional identifying characteristics such as watermarks. Based on the automated error correction, the additional code data are not output by the playback and display unit. A suitable verification unit can extract the code data from the random error data, which manifest itself as white noise by circumventing the error correction. Copying of the data media by illegal, professional copy devices would lead to a removal of the additional code, and would thus be clear criteria for an illegal copy.
20 Citations
14 Claims
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1. Device for copy protection of data media units (10) carrying digital documents, especially of optically readable data media, with
means for applying a digital content (2) of the digital document onto the data media unit in a physical or logical structure associated with the data media unit and means for applying additional code (3) onto the data media unit by predetermined change of the physical structure, so that during a regulated playback and/or display process of the digital data media unit by a regulation playback and/or display unit (15) the additional code is not captured and has no influence on the originating or displayed digital content of the digital document, characterized by verification means being provided for recognition of a legally produced specimen of the data media unit, which, by bypassing possible error correction or filtering units in the playback or display unit provided for a data media unit, enable immediate reader access to the additional code and makes it possible to determine, if the additional code is present and if it corresponds to the additional code applied by the application means.
Specification