Method of copy detection and protection using non-standard TOC entries
AssigneeKoninklijke Philips Electronics N.V.
InventorsPetrus Henricus Cornelius Bentvelsen, Paulus Franciscus Vollebregt
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Abstract
The invention relates to a method of copy detection of a record carrier. In one particular embodiment the table of content entries are mastered on the record carrier in a detectable non-standard way, e.g. the sequence of table of content entries is mixed or the number of repetitions is varied. According to another embodiment additional synchronization symbols are used in one or more subcode frames which can be detected by a read-out device in order to distinguish between an original or a copy of a record carrier.
Claims15
A method of using a replay device for detecting a copied record carrier having a table of contents, the method comprising acts of:
- providing at least one encoder device for
- mastering a table of contents on an original record carrier to include entries in a non-standard sequence, a standard table of contents having entries in a standard sequence indicating that the corresponding at least one record carrier is a copy;
- storing subcode data on said original record carrier in subcode frames of a subcode channel, each subcode frame comprising synchronization symbols and data symbols at predetermined positions within said subcode frame;
- and
- assigning and storing a number of additional synchronization symbols to at least one subcode frame at positions provided for data symbols;
- providing at least one decoder device for generating, during read-out of said subcode channel, a check signal indicating presence or absence of said additional synchronization symbols;
- and
- preventing copying of said record carrier if said check signal indicates the absence of additional synchronization symbols in said subcode frames, wherein the record carrier is an optical storage disk.
A method of using a read-out of at least one record carrier having a table of contents for indicating whether the at least one record carrier is authorized and wherein non-standard tables of contents are mastered on authorized record carriers to include entries in a non-standard sequence, a standard table of contents having entries in a standard sequence, the method comprising acts of:
- providing at least one decoder device for
- reading said table of contents;
- checking if said table of contents is standard or non-standard;
- and
- outputting a signal indicating if said table of contents is standard or non-standard, a standard table of contents indicating that the record carrier is not authorized and a non-standard table of contents indicating that the record carrier is authorized, wherein, on the record carrier, subcode data in subcode frames of a subcode channel is stored, each subcode frame comprising synchronization symbols and data symbols at predetermined positions within said subcode frame;
- reading-out said subcode channel;
- checking if additional synchronization symbols are stored to at least one subcode frame at positions provided for data symbols;
- outputting a check signal indicating the presence or absence of said additional synchronization symbols in at least one subcode frame;
- and
- preventing copying of said record carrier if said check signal indicates the absence of additional synchronization symbols in said subcode frames, wherein the record carrier is an optical storage disk.
A method of using at least one replay device for producing a read-out of a record carrier on which subcode data is stored in subcode frames of a subcode channel, the method comprising acts of:
- pre-recording the record carrier by an encoder each subcode frame to include synchronization symbols and data symbols at predetermined positions within said subcode frame
- reading out said subcode channel;
- checking if additional synchronization symbols are stored to at least one subcode frame at positions provided for the data symbols;
- and
- outputting a check signal indicating the presence or absence of said additional synchronization symbols in at least one subcode frame, absence of the additional synchronization symbols indicating that the record carrier is a copy and presence of the additional synchronization symbols indicating that the record carrier is an original, wherein the record carrier is an optical storage disk.
An apparatus for detection of a copied record carrier having a table of contents, the apparatus comprising:
- control unit for mastering a table of contents on an original record carrier to include entries in a non-standard sequence, a standard table of contents having entries in a standard sequence indicating that the corresponding at least one record carrier is a copy;
- a storage for storing subcode data on said record carrier in subcode frames of a subcode channel, each subcode frame comprising synchronization symbols and data symbols at predetermined positions within said subcode frame, and
- assigning unit for assigning and storing a number of additional synchronization symbols to at least one subcode frame at positions provided for data symbols so that during read-out of said subcode channel a check signal is generated indicating the presence or absence of said additional synchronization symbols and copying of said record carrier is prevented if said check signal indicates the absence of additional synchronization symbols in said subcode frames, wherein the original record carrier is an optical storage disk.
An apparatus for producing a read-out of a record carrier on which subcode data are stored in subcode frames of a subcode channel, the record carrier having each subcode frame prerecorded to include synchronization symbols and data symbols at predetermined positions within said subcode frame, the apparatus comprising:
- a reading unit for read-out of said subcode channel,
- a checking unit for checking by a processor if additional synchronization symbols are stored to at least one subcode frame at positions provided for the data symbols, and
- an output unit for outputting a check signal indicating the presence or absence of said additional synchronization symbols in at least one subcode frame, absence of the additional synchronization symbols indicating that the record carrier is a copy and presence of the additional synchronization symbols indicating that the record carrier is an original, wherein the record carrier is an optical storage disk.
A replay device for playing a record carrier, the replay device comprising:
- a decoder device for decoding subcode data stored in subcode frames of a subcode channel, each subcode frame is prerecorded to include synchronization symbols and data symbols at predetermined positions within said subcode frame, subcode frames of original record carriers are prerecorded to include at least one subcode frame comprising a number of additional synchronization symbols assigned and stored by an encoder at positions provided for data symbols,
- wherein during read-out of the record carrier of said subcode channel, a check signal can be generated by the decoder device in response to detection of said additional synchronization symbols, absence of the additional synchronization symbols indicating that the record carrier is a copy and presence of the additional synchronization symbols indicating an original record carrier, wherein the record carrier is an optical storage disk.
Dependencies are inferred from the claim text.