Classifications

• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
  • G11B7/007—Arrangement of the information on the record carrier, e.g. form of tracks, actual track shape, e.g. wobbled, or cross-section, e.g. v-shaped; Sequential information structures, e.g. sectoring or header formats within a track
  • G11B7/00736—Auxiliary data, e.g. lead-in, lead-out, Power Calibration Area [PCA], Burst Cutting Area [BCA], control information
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
  • G11B19/02—Control of operating function, e.g. switching from recording to reproducing
  • G11B19/04—Arrangements for preventing, inhibiting, or warning against double recording on the same blank or against other recording or reproducing malfunctions
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
  • G11B19/02—Control of operating function, e.g. switching from recording to reproducing
  • G11B19/12—Control of operating function, e.g. switching from recording to reproducing by sensing distinguishing features of or on records, e.g. diameter end mark
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
  • G11B20/00086—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
  • G11B20/00086—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy
  • G11B20/00572—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving measures which change the format of the recording medium
  • G11B20/00586—Circuits for prevention of unauthorised reproduction or copying, e.g. piracy involving measures which change the format of the recording medium said format change concerning the physical format of the recording medium
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B23/00—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture
  • G11B23/28—Indicating or preventing prior or unauthorised use, e.g. cassettes with sealing or locking means, write-protect devices for discs
  • G11B23/281—Indicating or preventing prior or unauthorised use, e.g. cassettes with sealing or locking means, write-protect devices for discs by changing the physical properties of the record carrier

Definitions

• the invention relates to an anti-piracy optical recording disc and to a method for reading such a disc.
• the invention can in particular be applied to optical discs in CD or DVD format but it also extends to any other format. Due to the appearance on the market of CD type recorders
• CD-R or CD-RW and soon DVD burners at low cost, duplication, in particular CD-ROM or DVD-ROM, has become or will become accessible to semi-professionals or amateurs.
• the subject of the invention is a disc and an anti-pirating reading method prohibiting unauthorized use of the stored information and in particular the use of pirated copies by using a disc having a specific physical configuration.
• the disc of the invention can be read by a conventional player, without modification. But its structure makes any copy by easily accessible means unusable and the structure of the disc cannot be simulated. In addition, the reproduction of such a disc cannot be done without very sophisticated and extremely expensive industrial means.
• an optical information recording disc comprising a continuous main recording track, recorded generally known in the form of a spiral comprising a plurality of successive turns, characterized in that the disc further comprises at least one section of secondary track interposed between two adjacent spiral turns, said section carrying at least one identification information specific to said section, a first information on the anti-piracy nature of the disc and a second information on the positioning of the section of secondary track relative to the main track, said first and second information being arranged in a zone of initialization of disc playback on the main track.
• a method for reading the above disc characterized in that it comprises the steps of: a) reading the information arranged on the main track in said initialization area; b) check that the physical structure of the disk conforms to that described by the information in the initialization area; c) authorize the use of the information carried by the main track and the operation of the corresponding application only when the result of the verification of step b) is positive.
• FIG. 1 is the diagram of a first embodiment of a disc according to the invention
• - Figure 2 shows a variant of the disc of Figure 1;
• FIG. 3 is another variant where the secondary track portion is assumed to occupy more than one revolution on the disc.
• Figure 1 shows an exemplary embodiment.
• a main track 1 in a spiral On the disc is provided a main track 1 in a spiral.
• This track is designed to carry information in a conventional manner, for example in accordance with the specifications of CD or DVD discs.
• a section of secondary track 2 is interspersed between two consecutive laps of the main track 1.
• This section is here assumed to be much shorter than one lap of the track.
• This section is arranged with a standard spacing between the turns of the main track, that is to say that the spacing between the adjacent laps of the main track is equal to the standard spacing between two normal adjacent laps of the main track. It can be seen that at the level of the secondary track section, the main track reaches a double gauge; the connection between the standard deviation and the double deviation must be made gradually so that a normal reader does not have to skip a track.
• the disc comprises on the main track an initial area 3, loading area or TOC or even area called “boot” in the Anglo-Saxon literature, which includes a first piece of information 30 on the anti-piracy nature of the disc and a second piece of information 31 on the positioning of the section of secondary track 2 relative to the main track.
• information 31 will indicate address A on the main track as well as an indication of a jump to track 10 on the right which will allow the reader to go to the start of section 2.
• Information 31 may also include the indication of the length of the section (or of the end address).
• the section 2 comprises at least one piece of recorded information identifying said section. This section may also include other information usable in anti-piracy protection.
• the operation for reading this disc is as follows.
• the player starts playing in the same way as a conventional disc; it necessarily centers on the main track, even if it passes for an instant through the secondary track section and goes to the initialization zone 3.
• There it reads information 30 and 31. This implies that the operation of the application and use of the information on the main track will only be authorized after verification that the physical structure of the disc conforms to that described in zone 3, which indicated that it was a anti-piracy disc and that a section 2 was at the positioning (start, length) determined by information 31.
• the reading method according to the invention provides for several possible verification methods mentioned above.
• the first step is, in all cases, to go to the start of the secondary runway section 2 and to verify the presence of the section specific identification information.
• a first possibility for this step is to indicate the address A on the main track facing the start of the section 2 and the direction of the jump of a track to be performed (here on the right in FIG. 1). But we could also go to the address A + 1 turn and make a jump to the left.
• a first method can consist in making the reader read, after address A, a complete revolution of the main track plus the expected length of section 2 (for example up to address A '). If the identification information for section 2 has not been found, it is because the disc has the advertised physical structure. Indeed, if we wanted to simulate section 2 on the main track, we would necessarily meet it from address A + 1 lap. It is clear that this verification can be carried out at the start of the use of the disc but also randomly during the use of the disc, which further increases the difficulty of copying the disc by simulating its structure.
• FIG. 2 represents a variant which makes pirating a disk even more difficult.
• This figure shows the main track 1, the initialization zone 3 and the first section of secondary track 2.
• a second section of secondary track 4 is provided, inserted in another position between two (or more) laps main.
• the positioning information 20 of this second section 4 is carried by the first section 2.
• this information is relatively hidden.
• FIG. 3 illustrates another embodiment where the section of secondary track 2 ′ has a length greater than one complete revolution. This does not change the process described above.
• the anti-piracy protection can be further improved by recording on the secondary track section or sections other information than that of identification.
• the advantages of the invention are numerous.
• the main track information is read transparently by standard readers. Only basic access / read functions of the reader are used, activated beforehand or during the course of the application and the use of the information on the disc. This leads to good compatibility with standard means of implementation of drives and application processes and an additional difficulty in simulating operation with copy disks, since it is more difficult to identify the use of disk identification when this recourse takes place during the usage program.
• the effectiveness of the anti-piracy according to the invention is all the greater when the general public users of current recorders cannot implement the structure described.
• the positioning and the length of the secondary track section or sections may vary from one type of disc to another, it is not possible to produce special recordable discs intended for pirated copying of the discs according to the invention .

Landscapes

• Engineering & Computer Science (AREA)
• Computer Security & Cryptography (AREA)
• Signal Processing (AREA)
• Optical Recording Or Reproduction (AREA)
• Signal Processing For Digital Recording And Reproducing (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=9533997

Family Applications (1)

Country Status (6)

Families Citing this family (3)

Family Cites Families (35)

• 1998
  • 1998-12-15 FR FR9815833A patent/FR2787232B1/fr not_active Expired - Fee Related
• 1999
  • 1999-12-10 WO PCT/FR1999/003103 patent/WO2000036601A1/fr not_active Application Discontinuation
  • 1999-12-10 JP JP2000588767A patent/JP2002532820A/ja active Pending
  • 1999-12-10 EP EP99958304A patent/EP1159742A1/de not_active Withdrawn
  • 1999-12-10 US US09/600,887 patent/US6452886B1/en not_active Expired - Fee Related
  • 1999-12-10 AU AU15694/00A patent/AU1569400A/en not_active Abandoned

Non-Patent Citations (1)

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