WO2004023476A1

WO2004023476A1 - Information recording/reproduction medium, information recording/reproduction device, information recording/reproduction method, and information recording/reproduction medium data structure

Info

Publication number: WO2004023476A1
Application number: PCT/JP2003/011206
Authority: WO
Inventors: Masatsugu Ogawa; Kinji Kayanuma; Shigeru Shimonou
Original assignee: Nec Corporation
Priority date: 2002-09-03
Filing date: 2003-09-02
Publication date: 2004-03-18
Also published as: JP2004095114A

Abstract

A digital content is divided into a digital content frame unit and sync pattern information (23) or encryption key information (24) is inserted between the frames and recorded on a medium. A part of the divided digital content is encrypted so that it can be restored according to encryption key information (26) and recorded as encryption information data (27). When the encryption key information (26) and the encryption information data (27) are both read out normally from the medium, the digital content is reproduced. Thus, it is possible to easily realize copy protection.

Description

Information recording / reproducing medium, information recording / reproducing device, information recording / reproducing method, and

Data structure of information recording / reproducing media

The present invention relates to a data structure of an information recording / reproducing medium, and more particularly, to a data structure of an information recording medium for restricting copying of content. The present invention further relates to an information recording / reproducing medium, an information recording / reproducing apparatus, and an information recording / reproducing method for recording and reproducing such a data structure. Background art

Large-capacity optical discs represented by DVDs include read-only optical discs (DVD-ROM), write-once optical discs (DVD-R) that can be recorded only once, and rewritable optical discs (DVD-RW). These media store video, music, or digital contents such as data. Since the digital contents stored on these media have compatible data formats, for example, in principle, the contents recorded on a DVD-ROM can be copied directly to a DVD-R as it is in principle.

By the way, since the content recorded on the DVD-ROM is digital content, there is no deterioration even if copying is repeated. Therefore, if the content is copied illegally, the copyright of the content creator is seriously violated. In order to prevent unauthorized copying and protect the copyrights of content producers, recordable media such as DVD-R and DVD-RW may be used even if the entire contents of DVD-ROM are copied. , To prevent content playback A pair is adopted.

In general, a DVD is provided with a control data zone for recording information indispensable for recording or reproduction of a disc. The content of the content and the control information recorded in the control data area are matched. Content is allowed to be played. In the conventional write-once type DVD-R, predetermined information is fixedly recorded in the control data area before and after shipment of a medium as a measure against illegal copying (copy protection). For this reason, for example, even when the entire content of the DVD-ROM is copied to the DVD-R, the content of the content data does not match the information recorded in the control information area, and the content data is not copied. Evening playback does not take place.

In the rewritable type DVD-RW, unlike the above, an emboss is formed in the control data area in advance. In this case, even if normal control information is written in the control data area, the information causes interference with the emboss, and normal reading of the written control information becomes impossible. For this reason, even if the entire contents of the DVD-ROM are copied to the DVD-RW, the playback of the content data becomes impossible.

By the way, a guide groove for tracking control of the optical head is formed at 0 ¥ 0—length ゃ 1 ¥ 0—1 ^ ¥. In DVD-RW, the distance between an emboss formed in the control data area and a guide groove for tracking control is distinguished by the depth of both grooves (recesses). In the DVD-RW, since the embossing and the guide groove are formed at different depths as described above, when producing a stamper master for the production of the DVD-RW, strong light is generated in a portion where the embossing is formed. It is necessary to form the groove deep by exposing the light and to form the groove shallowly by exposing the light to the part where the guide groove is formed. For this reason, there was a problem that the manufacturing process of the disk became complicated. In addition, as described above, in DVD-R, after the media is manufactured and before it is shipped, the control data is stored on each disk. Since information must be recorded in the area, there is a problem that productivity is low. Disclosure of the invention

An object of the present invention is to provide a data structure of an information recording / reproducing medium that can easily prevent reproduction of copied content data in view of the above problems.

Another object of the present invention is to provide an information recording medium, an information recording / reproducing apparatus, and an information recording Z reproducing method capable of recording / reproducing data having the above data structure.

According to the present invention, there is provided information in which a data signal is divided into a plurality of frame data each having a predetermined data length and recorded, and a timing synchronization signal is recorded in at least a part of a space between adjacent frame data. In the recording medium, encryption key information is recorded in part or all of an area where the timing synchronization signal is recorded, and at least a part of the decryption signal can be restored by the encryption key information. An information recording medium characterized by being recorded as described above. In the information recording medium of the present invention, a data signal such as digital content is recorded in units divided into a plurality of frames. In the conventional data structure (format), a sync pattern for timing synchronization is formed between a plurality of frames and recorded on the medium. In the present invention, however, the area of the area on the medium where the sync pattern is to be formed is Partially or entirely record the key information. At least a part of the digital content divided into frames is converted to be recoverable by the encryption key information and recorded on a medium. Digital contents are recorded on the medium in a sync pattern or a data format in which encryption key information is inserted between frames. By adopting this data format, the digital content recorded on the medium will not be able to read the original data unless the encryption key information is read correctly. — Cannot be restored in the evening. For this reason, even if digital content is copied from an information recording medium, it is impossible to correctly read the encryption key information from the copied medium, so that normal reproduction of the content becomes impossible, and the content is illegally copied. Can protect the copyright of the copyright owner.

The present invention relates to a recording data structure for a data signal recorded on an information recording medium, comprising: a data signal divided into a plurality of frame data each having a predetermined data length; A timing synchronization signal recorded in a space of the timing synchronization signal, and encryption key information inserted between the frame data instead of a part of the timing synchronization signal or added to at least a part of the timing synchronization signal. And wherein at least a part of the data signal is converted so as to be recoverable by the encryption key information.

In the data structure of the present invention, the digital content is composed of digital content divided in frame units and a sync pattern for timing synchronization or encryption key information inserted between frames, and at least a part of the divided digital content is It is configured as a format that can be restored to the original digital content using the encryption key information. Even when the content is recorded on a recording medium using this format, by preventing the encryption key information from being read correctly from the medium, the content cannot be normally reproduced, and the content cannot be reproduced. Even if copied illegally, the copyright of the copyright holder can be protected.

In the information recording medium and the data structure of the present invention, the data signal may be configured as an encrypted data encrypted so as to be recoverable by the encryption key information, or The information may be configured based on data obtained by cutting out a part of the data signal. Various combinations of the encryption key information and the data signal divided into frames are conceivable. Whatever combination, dark Unless the key information and the data portion corresponding to the content data are read out in a pair, normal reproduction of the content is prevented from being performed, thereby realizing copy protection.

According to another aspect of the present invention, a data signal is divided into a plurality of frame data each having a predetermined data length, and a timing synchronization signal is recorded in at least a part of a space between adjacent frame data. In an information recording medium that employs a recording format, a pre-pit is formed in a synchronization signal recording area where the timing synchronization signal is to be recorded, and the pre-pit is recorded in the synchronization signal recording area. Provided is an information recording medium having a function of inhibiting signal reproduction.

In an information recording medium according to another aspect of the present invention, a prepit (emboss) is formed in a synchronous signal recording area where a timing synchronization signal is recorded. The pre-pits are formed so as to interfere with the signal pattern when reproducing a signal recorded in the area where the pre-pits are formed, thereby preventing normal reading. As a result, digital content in the overnight format, in which the reproduction of the content is permitted by reading the signal recorded in the synchronization signal recording area normally, becomes impossible, and the illegal reproduction of the content becomes impossible. And protect the copyright of the copyright holder. The pre-pits should be formed so as to prevent normal reading of signals recorded in the area where the pre-pits are formed, and not to make it impossible to read a sync pattern composed of long marks or spaces. In the information recording medium according to another aspect of the present invention, the pre-pits may include address information. Since the purpose of the pre-pit is to prevent reading of a signal recorded in the area where the pre-pit is formed, the pre-pit itself may have information such as an address signal on a disk. You do not have to have any information. In an information recording medium according to another aspect of the present invention, it is preferable that the depth of the pre-pit is substantially the same as the depth of a guide groove for tracking control. Since the guide groove and the pre-pit do not interfere with each other, the recess of the pre-pit and the guide groove can be formed at the same depth. In this case, the guide groove and the pre-pit can be formed at once, and the process required for manufacturing the information recording medium is simplified. The present invention provides an information reproducing apparatus for reproducing a data signal from the information recording medium of the present invention, wherein the information reproducing apparatus stores an algorithm for decrypting the data signal based on the encryption key information. Provide equipment.

The information reproducing apparatus of the present invention stores an algorithm for restoring a data signal recorded so as to be restored based on the encryption key information to an original data signal. When reproducing digital content from the information recording medium of the present invention, the encryption key information is read from the information recording medium, and the read encryption key information is used to restore a data signal by a predetermined algorithm, thereby reproducing the content. Do. When digital content is recorded on the information recording medium of the present invention in the data structure of the present invention, the information reproducing apparatus cannot correctly read the No. key information, and the digital content cannot be reproduced. Not done. As described above, the information reproducing apparatus does not reproduce the digital content copied illegally, and the copyright of the copyright holder of the digital content is protected.

The present invention is an information recording apparatus for recording a data signal on the information recording medium of the present invention, wherein at the time of recording the data signal, at least a part of a synchronization signal recording area in which the pre-pit is formed in advance, An information recording device characterized by recording the encryption key information is provided.

In the information recording apparatus of the present invention, when digital content is recorded on the information recording medium of the present invention, the encryption key information is recorded in at least a part of the area where the prepit is formed. In other words, at least part of the encryption key information is It is recorded in the area where the pit is formed. Prepits cause interference with signals recorded in the area where the prepits are formed and hinder normal reading of signals.Therefore, even when an information recording medium recorded by an information recording device is reproduced by an information reproducing device, However, digital content is not played back normally, and the copyright of the copyright holder of the digital content is protected.

According to another aspect of the present invention, there is provided an information recording apparatus that divides a data signal into a plurality of frame data each having a predetermined data length and records the data signal on a recording medium. Encrypting means for encrypting at least a part of the encrypted data to generate encrypted data; at least a part of a space between adjacent frame data, a timing synchronization signal, and at least one of encryption key information for restoring the encrypted data; Recording means for recording the data signal while inserting the data signal.

In an information recording apparatus according to another aspect of the present invention, the encrypting means encrypts at least a part of the digital content divided into frame units. The recording means records digital contents while inserting at least one of a sync pattern for timing synchronization and encryption key information between frames. Using this information recording device, a stamper master for manufacturing an information recording medium can be manufactured. By using this stamper master, the content is recorded at a low cost and in a data format that realizes copy protection. Information recording medium can be obtained. Note that the encryption used in the present invention may not be for the purpose of concealing data, and the encryption may be converted so that a data signal cannot be restored without using encryption key information. included.

The present invention relates to an information recording method for recording a data signal on an information recording medium, wherein the data signal is divided into a plurality of frame data each having a predetermined data length, and at least a part of the frame data is At least partially encrypted Recording the data signal while inserting at least one of a timing synchronization signal and encryption key information for restoring the encrypted data into at least a part of a space between adjacent frame data. An information recording method characterized by the following is provided.

In the information recording method of the present invention, digital content to be recorded is divided into predetermined frame units, at least a part of the divided digital content is converted by a predetermined algorithm, and a sync for timing synchronization is provided between frames. Record by inserting the symbol key information for restoring the pattern or converted digital content to the original digital content. Digital content recorded using this method cannot be played unless the 喑 No. key information is read correctly, preventing unauthorized copying of digital content and ensuring Rights can be protected.

According to the present invention, in an information reproducing method for reproducing a data signal recorded by the information recording method of the present invention, the encrypted data and the encryption key information are read, and the encrypted data is read based on a predetermined algorithm. And reproducing the data signal while restoring the data signal based on the encryption key information.

In the information reproducing method of the present invention, when reproducing the digital content recorded by the recording method of the present invention, the digital content converted by a predetermined algorithm and the 喑 key information are read, and a predetermined algorithm and Restores the converted digital content to the original digital content according to the reverse algorithm. Since the digital content is not played back when the No. 1 key information is not correctly read, it is possible to prevent unauthorized copying of the digital content and protect the copyright of the copyright holder.

According to another aspect of the present invention, there is provided an information recording apparatus for recording a data signal on an information recording medium. In the recording method, the data signal is divided into a plurality of frame data each having a predetermined data length, and at least a part of a space between adjacent frame data includes a timing synchronization signal, and a creator ID. An information recording method is provided wherein the data signal is recorded while at least one of ID signals including information is inserted.

The present invention further provides an information reproducing method for reproducing a data signal recorded by the information recording method according to another aspect of the present invention, wherein the data signal and the ID signal are read from an information medium, The present invention provides an information reproducing method characterized in that when the ID information obtained based on the ID signal matches the stored regular ID information, the overnight signal is reproduced.

Even if the ID signal is read from the information recording medium properly, it is possible to prevent the illegal copying of the digital content and protect the copyright of the copyright holder by using a configuration that enables the reproduction of the data signal. Becomes possible.

As described above, according to the information recording medium, the information recording / reproducing apparatus, the information recording Z reproducing method, and the data structure of the information recording medium of the present invention, the content can be reproduced unless the encryption key information is normally read. Adopt a configuration that does not. Since the information recording medium is constructed such that it is difficult to read the information recorded in the portion where the encryption key information is to be written when the information recording medium is manufactured, the information recording medium includes the data of the present invention. Even if the content is copied from an information recording medium in which the content is recorded in a structure, the content cannot be reproduced and the copyright of the content creator is protected.

Note that the information reproducing device of the present invention may also serve as an information recording device, and the information recording device of the present invention may also serve as an information reproducing device. The information recording medium of the present invention may be a medium capable of recording and reproducing desired information, or may be a read-only recording medium. The information recording medium of the present invention is typically Although it takes the form of a disc, it may be in any form such as a tape. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram showing a data structure of one physical section read from an optical disc according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing, as a comparative example, a data structure of one physical section of content data read from a conventional optical disc.

FIG. 3 is a block diagram showing a configuration of an information recording apparatus that generates a stamper master used when recording content data in a data format according to the first embodiment.

FIG. 4 is a block diagram showing a configuration of an optical disk device for reading data stored on an optical disk according to the first embodiment.

FIG. 5 is a schematic diagram showing a part of a track of a write-once optical disc or a rewritable optical disc used as the optical disc 20.

FIG. 6 is a block diagram showing a configuration of a sync frame including code key information of a data structure recorded on an optical disc according to the second embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of an optical disk device for reading data recorded on an optical disk according to the second embodiment.

FIG. 8 is a block diagram showing a configuration of a sync frame including content provider ID information of a data structure recorded on the optical disc according to the third embodiment of the present invention. -FIG. 9 is a block diagram showing a configuration of an optical disc device that reads data recorded on an optical disc according to the third embodiment. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to the drawings based on an embodiment of the present invention. FIG. 1 shows a data structure of one physical sector read from the optical disc according to the first embodiment of the present invention. One physical sector of the optical disk (information recording medium) is composed of a plurality of (synchronous frames) 22 and 25 (26 in the example of FIG. 1). The plurality of sync frames include two types of sync frames. The first type of sync frame 22 includes sync pattern information 23 and information data 24, and the second type of sync frame 2 4 is composed of # key information 25 and encrypted information data 26. In the example of the figure, of the 26 sync frames, the odd-numbered sync frame is configured as the first type of sync frame 22 and the even-numbered sync frame is the second type of the sync frame. It is configured as sync frame 24.

Referring to FIG. 2, a data structure of one physical sector of content data read from a conventional optical disc is shown as a comparative example. In the conventional data structure, the sync pattern 43 and the information data 44 constitute one sync frame 42, and a plurality of sync frames 42 constitute one physical sector 41. One sync frame 42 is obtained by dividing content data into information data having a predetermined length of data and adding sync pattern information 43 for timing synchronization to the information data. As shown in FIG. 2, one physical sector 41 in the conventional data format is composed of only the sync frame 42 including the sync pattern information 43 and the symbol key information 26 shown in FIG. Is not included.

The sync frame including the sync pattern information of the data format shown in FIG. 1 and the sync frame including the symbol key information are obtained as follows. First, content data is divided into information data having a predetermined data length. Next, the content creator (provider) sets the encryption key information arbitrarily and sets the set key code. Encrypts information data to generate encrypted information data so that it can be decrypted (restored) by one piece of information. Then, encryption key information for decrypting the encryption information data is added to the encryption information data, and a sync frame including the encryption key information is obtained. The sync frame including the sync pattern information is obtained by adding the sync pattern information to the divided information data.

Referring to FIG. 3, there is shown a configuration of an information recording apparatus for generating a stamper master used when recording content data in the data format of the first embodiment. The information recording device 30 includes an objective lens 31, an LD 32, an LD drive circuit 33, a code generation mechanism 34, and a spindle control circuit 35. The objective lens 31 irradiates the laser beam output from the LD 32 controlled by the LD drive circuit 33 onto the stamper master 36. The spindle control circuit 35 controls the rotation of the stamper master 36.

On the stamper master 36, content data is formed on a read-only optical disc such that the content data is recorded in the data format shown in FIG. The encryption generation mechanism 34 generates the encryption information data based on the set encryption key information, and controls the LD drive circuit 33 to write the encryption information data and the encryption key information on the stamper master 36. I do. Using the stamper master 36 thus obtained, through a process such as injection molding, a read-only optical disk in which desired contents are recorded in the data format shown in FIG. 1 is obtained.

Referring to FIG. 4, there is shown a configuration of an optical disc apparatus for reading data recorded on the optical disc of the first embodiment. The optical disk device 10 includes an objective lens 11, a laser diode (LD) 12, an LD driving circuit 13, a photodetector 14, a decoding circuit 15, and a spindle driving circuit 16. When reading one physical frame from the optical disk 20, the optical disk device 10 reads the encryption key information from the sync frame including the encryption key information included in the one physical frame. Then, the encrypted information is decrypted using the encryption key information, and the content is reproduced. As the optical disk 20 from which the optical disk device 10 reads data, a read-only optical disk, a write-once optical disk, or a rewritable optical disk can be used. , LD drive circuit 13 controls the output of LD 12. The objective lens 11 irradiates the recording surface of the optical disc 20 with the laser light output from the LD 12. The spindle drive circuit 16 rotates the optical disc 20. The objective lens 11 receives the reflected light of the laser beam irradiated by itself, and inputs the incident light to the photodetector 14. The photodetector 14 detects data recorded on the optical disc 20 based on the reflected light from the optical disc 20. The decrypting means 15 extracts the encryption key information from the data detected by the photodetector 14 and decrypts the encrypted information data. When a read-only optical disk manufactured by using the stamper master 36 as the optical disk 20 is reproduced by the optical disk device 10, the encryption key information can be correctly read, and the content is reproduced.

Referring to FIG. 5, a part of a track of a write-once optical disc or a rewritable optical disc used as the optical disc 20 is shown. In the write-once type and rewritable type optical disks 20 of this embodiment (both types are hereinafter referred to as recording types), as shown in FIG. 5, the sync pattern of the sync frame shown in FIG. An emboss (pre-pit) 28 of address information and the like is formed in an area in a track where the information 23 or the encryption key information 26 is to be recorded, and its concave portion is formed at the same depth as the guide groove 29. For this reason, the emboss 28 and the guide groove 29 can be collectively formed with the same exposure time.

When the entire content data is copied from the read-only optical disk stored in the data format shown in FIG. 1 to the recordable optical disk of this embodiment using the information recording device, the sync frame 2 Encryption key information included in 5 26 is written in the area where the emboss 28 shown in FIG. 5 is formed. When this recordable optical disk is read by the optical disk device 10, the emboss 28 and the encryption key information 26 interfere with each other, and the encryption key information 26 is not accurately read and the encrypted information data 27 is normal. Cannot be decrypted. For this reason, content data cannot be normally reproduced on a recordable optical disc in which the content data is copied from a read-only optical disc.

Instead of the above, when content is written in the conventional format as shown in FIG. 2 on the recordable optical disc on which the embossment 28 shown in FIG. 5 is formed, the sync pattern information 43 is replaced by the embossment 28. It will be written to the formed area. In this case, the sync pattern information 43 and the emboss 28 cause interference. However, the sync pattern information 43 is composed of long marks and long spaces, and there is little interference with the emboss 28. It is not impossible. As described above, emboss 28 does not function as copy protection for content data written in a conventional format, and normal content can be reproduced.

In the present embodiment, as described above, one physical sector 21 is composed of a sync frame 22 including sync pattern information 23 and a sync frame 25 including symbol key information 26. Formats are used to record content data on a read-only optical disc. A part of the content data is encrypted and recorded on the read-only optical disc recorded in this data format so that the content data cannot be correctly reproduced unless the encryption key information is read. For this reason, even if the information data part (information data or encrypted information data) can be read, the content is not reproduced only by that data. -When manufacturing a recordable optical disc, an emboss 28 is formed in an area where the sync pattern information 23 or the symbol key information 26 is to be recorded. like this When the content recorded in the data format adopted in the present embodiment is copied onto a simple recordable optical disc, the encryption key information 26 interferes with the emboss 28, so that the optical disc apparatus 10 uses the encryption key information. 26 cannot be read satisfactorily, making content playback impossible. As a result, illegal copying of content from a read-only optical disc to a recordable optical disc becomes practically impossible, and copy protection is realized. In addition, since the sync pattern information is usually composed of a long space and a long mark, the optical disc apparatus 10 can reproduce the content recorded on the recordable optical disc in the same format as in the past (FIG. 2). This can be performed in the same manner as in the related art.

As described above, if the content is recorded on the read-only optical disc using the data format of the present embodiment, the copyrighted content cannot be illegally copied to the recordable optical disc. Consumers can safely provide content to general consumers without worrying about illegal copying. As a result, the supply of contents becomes active and can greatly contribute to the development of the optical disc industry.

In conventional write-once optical discs (DVD-R) as copy protection, it was necessary to write information one by one in the control data area after the medium was manufactured and before shipment. In the process, the embossment 28 may be formed at once, so that the productivity of the medium is improved. In the conventional rewritable optical disc (DVD-RW), the control data area is formed with an embossing with a different depth so as to be distinguished from the guide groove. The concave portion of the embossment 28 formed inside can be formed at the same depth as the guide groove 29, so that a stamper master can be generated with a single exposure, simplifying the media manufacturing process. . In this embodiment, since such a recordable optical disk is used, the cost is not increased as compared with the prior art, and copy protection can be performed reliably and easily. Manifest.

Referring to FIG. 6, there is shown a configuration of a sync frame including encryption key information having a data structure recorded on an optical disc according to the second embodiment of the present invention. In the first embodiment, copy protection is realized by encrypting information data and writing encryption key information used for decryption in an area where the emboss 28 shown in FIG. 5 is formed. In addition to this, copy protection prevents the content from being reproduced unless the information written in the embossed area 28 shown in FIG. 5 and the information data are read as a pair. It becomes feasible. Therefore, in the present embodiment, instead of encrypting the information data, the encryption key information is constituted by data at a predetermined position in the information data, and if the encryption key information is not read out normally, the content is not read. Disable playback.

As shown in FIG. 6, in the divided content data 52, data 53 at a predetermined position is cut out from the content data 52, and according to a predetermined conversion rule, the cut data is a dummy data string “0”. It is converted to the pseudo information data 54 replaced by “0 0 0”. The cut data 53 is added to the pseudo information data 54 as encryption key information 53A. That is, the pseudo data information 54 partially cut out from the original information data and the キ sign key information 55 composed of the cut out data constitute one sync frame.

The pseudo information database 54 does not employ encryption for concealing content data, but since some data is cut off, it must be read in pairs with the corresponding encryption key information. Content does not play. Since the key information is used as a key for restoring the pseudo information data, it can be considered as a key for decrypting. In the present embodiment, a data format composed of a sync frame is used for the sync frame 25 shown in FIG. The read-only optical disc according to the present embodiment uses this data format to copy data. Record the content data.

Referring to FIG. 7, there is shown a configuration of an optical disc apparatus for reading data recorded on the optical disc of the second embodiment. The present embodiment is different from the optical disc device of the first embodiment in that the decoding means 15 shown in FIG. 4 is replaced by the decoding means 17. The decoding means 17 stores a restoration rule (algorithm) for restoring the pseudo information data in which a part of the data string has been replaced with a dummy data string according to the conversion rule to the original information data. Alternatively, the restoration rule may be stored in a predetermined area of the optical disk 20. The decryption means 17 embeds the encryption key information composed of the cut data in the pseudo information data according to the restoration rule to generate the original information data.

When the optical disc apparatus 10 reproduces a read-only optical disc in which the content is recorded in the data format used in the present embodiment, the decoding means 17 restores the pseudo information data to the data Is played. However, the entire content data is copied from the read-only optical disc to a recordable optical disc having an embossment formed in a predetermined area similar to that shown in FIG. 5, and the recordable optical disc is reproduced by the optical disc apparatus 10. Then, similarly to the first embodiment, the symbol key information cannot be read. For this reason, the decoding means 17 cannot recover the pseudo information, and cannot reproduce the content. When the content is recorded on the recordable optical disc in the conventional data format shown in FIG. 2, the content can be normally reproduced in the same manner as in the first embodiment.

In the present embodiment, as described above, the encryption key information is constituted by a part of the information data. The information data is converted to pseudo-information data by replacing a part of the information data with a dummy data string. Content data is recorded on a read-only optical disc in a data format including a sync frame composed of encryption key information and pseudo information. Thus, a read-only optical disk If the recorded content is copied to a recordable optical disc having an embossed position at a predetermined position, it becomes impossible to read the encryption key information and normal reproduction of the content becomes impossible. Therefore, as in the first embodiment, copy protection is realized reliably and easily.

The present inventors prototyped a read-only optical disk for recording content in the data format of the present embodiment and an optical disk device 10 of the present embodiment having the configuration shown in FIG. Using this optical disc device, we reproduced the prototype read-only optical disc and confirmed that the content could be reproduced well. Furthermore, a prototype of a recordable optical disk having an emboss 28 as shown in FIG. 5 was produced, and the contents recorded on the prototype read-only optical disk were copied to the recordable optical disk. When the copied recordable optical disk was played back on the same optical disk device as the prototype read-only optical disk, the content could not be played back well. As a result, it was confirmed that effective copy protection can be easily and reliably realized by using the data format of the read-only optical disk, the read-only optical disk, the recordable optical disk, and the optical disk device of this embodiment. Was done. Referring to FIG. 8, there is shown a configuration of a sync frame including content provider ID information of a data structure recorded on an optical disc according to the third embodiment of the present invention. This embodiment differs from the first and second embodiments in that the sync pattern information 43 shown in FIG. 2 has a sync frame 61 that replaces the content provider ID information 63 shown in FIG. I do. The content provider ID information 63 is generated based on, for example, an ID key registered at a standard meeting or the like, or an ID key allocated from a planning meeting or the like. In the present embodiment, for example, the data format in which the sync frame 25 shown in FIG. 1 is composed of the sync frame 61 shown in FIG. 8 is adopted. The read-only optical disc of the present embodiment records content data using this data format. Referring to FIG. 9, there is shown a configuration of an optical disc apparatus for reading data recorded on the optical disc of the third embodiment. The optical disc device 10 differs from the optical disc device 10 of the first embodiment in that the decoding means 15 shown in FIG. 4 is replaced with the ID confirmation means 18. The ID confirmation unit 18 stores a registered ID key and a rule for specifying the ID key from the content provider ID information read from the optical disc 20. The ID confirmation unit 18 identifies the ID key from the content provider ID information and checks whether the ID key is a registered ID key. As a result of the investigation, when it is confirmed that the specified ID key is registered, the content data is reproduced. When the specified ID key is different from the registered ID key, or when the ID key cannot be specified, the content is not reproduced.

When the read-only optical disk device is played back on the optical disk device 10, the ID confirmation means 18 identifies the ID key correctly from the content provider ID information, confirms that the ID key is registered, and confirms the content. To play normally. However, if the content recorded on the read-only optical disc device is copied to the recordable optical disc having the embossed 288 shown in Fig. 5, the content provider ID information is recorded in the area where the embossed 288 is formed. Is done. When this recordable optical disc is reproduced by the optical disc device 10, the ID confirmation means 18 cannot correctly read the content provider ID information, and the content is not reproduced. When the content is recorded on the recordable optical disc in the conventional data format shown in FIG. 2, the content can be normally reproduced as in the first embodiment.

In the present embodiment, instead of the encryption key information, the content provider ID information is recorded, and the optical disc device 10 confirms that the ID key specified from the content provider ID information is registered. Re-content Perform life. If content recorded on a read-only optical disc is copied to a recordable optical disc with an embossed position, the content provider cannot read the ID information and cannot identify the ID key. Normal playback of the content becomes impossible. For this reason, as in the first embodiment, copy protection is realized reliably and easily. '

Although FIG. 1 illustrates an example in which the odd number of the sync frame has the symbol key information, the present invention is not limited to this, and the sync frame including the encryption key information may be an even number. Also, the number of sync frames including the symbol key information does not need to be the same as the number of sync frames including the sync pattern information, and it is sufficient that at least one sync frame is included in one physical section. For example, the sync frame including the encryption key information may be about 1 Z4 of the sync frame included in one physical sector, and for a certain physical sector, all the sync frames may include the symbol key information. It may be configured by a frame.

In the first embodiment, an example in which the emboss itself shown in FIG. 5 has address information has been described. In the emboss, the area to be formed is recorded with a sync pattern, encryption key information, or content provider ID information. If it is an area that should be, it will function as a copy protection, so the information of the emboss itself has nothing to do with the copy protection function. Thus, the emboss may have other useful information or no information at all. However, since the emboss is formed for the purpose of obstructing the reproduction of the recording signal, it is not preferable that the emboss is small enough not to affect the recording signal formed on the emboss or conversely too large. However, it is desirable that several types of embosses having an appropriate length are randomly arranged.

In the above embodiment, an example in which the stamper master 36 is manufactured using the information recording apparatus shown in FIG. 3 has been described. However, the information recording apparatus shown in FIG. It can also be used in the authoring process, which is a scribble before preparing 6. The combination of the encryption key information and the information data is not limited to those described in the above-described embodiment, and any combination of the encryption key information and the information data may be used so long as the content data can be reproduced as a pair. In the third embodiment, the content is reproduced when the ID key is specified from the content provider ID information. In the first embodiment, this ID key may be adopted as the encryption key information. In addition, the area where the emboss is formed as shown in FIG. 3 does not have to exactly match the area where the content provider ID information is to be recorded, and the sync pattern, symbol key information, and X do not need to be exactly the same. The data may protrude into the area where the information data is to be recorded.

In the second embodiment, an example has been described in which the divided content data is replaced with a dummy data sequence “0 0 0 0”. However, the dummy data sequence, the data sequence length, the divided content The conversion rule such as a predetermined position in the data can be changed as appropriate. For example, the dummy data string need not be “0000”. Also, the data cut by the conversion rule need not necessarily be concentrated in a part of the content data, and may be distributed in the content data. It may be a rule. In the third embodiment, the content provider ID information 63 may be configured so that an ID key can be specified from the content provider ID information included in one sync frame, or may be included in a predetermined number of sync frames. By combining the content provider ID information to be used, one ID key may be specified. For example, content provider ID information existing in one physical sector may be combined in accordance with a predetermined rule so that one ID key is specified. The content provider information 63 should have a complicated structure so that the ID key cannot be easily identified. In the above embodiment, an optical disk is described as an example of an information recording medium. However, the present invention is not limited to this, and various types of recording such as a phase-change recording film, an organic recording film, and an MO (magneto-optical recording film) are used. When a semiconductor storage device such as an R〇M or RAM is used as an information recording medium as well as a disc, contents are recorded on the information recording medium using the data format adopted in the above embodiment. can do. When an optical disk type information recording medium is employed, it does not depend on the laser wavelength of the optical head that performs the recording or reproduction. For example, a red laser of about 600 nm can be used, or a blue laser of about 400 nm can be used. Since the data format adopted in the above embodiment does not depend on the modulation code, various modulation and decoding such as EFM plus and 117 modulation can be adopted.

As described above, the present invention has been described based on the preferred embodiments. However, the present invention is not limited to the above embodiments, and various modifications and changes may be made from the configuration of the above embodiments. What is done is also included in the scope of the present invention.

Claims

The scope of the claims

1. A data signal is recorded by dividing into a plurality of frame data (24, 27) each having a predetermined data length, and is recorded in at least a part of a space between adjacent frame data (24, 27). In the information recording medium on which the timing synchronization signal (23) is recorded,

Encryption key information (26) is recorded in part or all of the area where the timing synchronization signal (23) is recorded,

An information recording medium, wherein at least a part of the data signal is recorded so as to be recoverable by the encryption key information.

2. The information recording medium according to claim 1, wherein the at least a part of the data signal (27) is encrypted data that has been encrypted so as to be able to be restored by the key information.

3. The information recording medium according to claim 1, wherein the encryption key information is configured by data obtained by cutting off a part of the data signal.

'

4. The data signal is divided into a plurality of frame data (24, 27) each having a predetermined data length, and at least a part of the space between adjacent frame data (24, 27) includes a timing synchronization signal ( 23) In an information recording medium employing a recording format in which

A prepit (28) is formed in a synchronization signal recording area where the timing synchronization signal (23) is to be recorded, and the prepit (28) reproduces a signal recorded in the synchronization signal recording area. Information characterized by the function of inhibiting Information recording medium.

5. The information recording medium according to claim 4, wherein the pre-pit (28) includes address information.

6. The information recording medium according to claim 4, wherein a depth of the pre-pit (28) is substantially the same as a depth of a guide groove (29) for tracking control.

7. An information reproducing apparatus for reproducing a data signal from the information recording medium according to any one of claims 1 to 3, wherein an algorithm for decrypting the data signal based on the encryption key information is stored. Information reproducing device.

8. An information recording device for recording a data signal on the information recording medium according to any one of claims 4 to 6, wherein the pre-pit (28) is formed in advance when recording the data signal. An information recording device for recording encryption key information in at least a part of a synchronization signal recording area.

9. In an information recording apparatus for dividing a data signal into a plurality of frame data (24, 27) each having a predetermined data length and recording the data on a recording medium, at least a part of the frame data (2 7) an encrypting means for encrypting at least a part of the encrypted data to obtain encrypted data;

At least one of a timing synchronization signal (23) and encryption key information for restoring the encrypted data (27) is inserted into at least a part of the space between adjacent frame data (24, 27). A recording unit for recording the data signal.

10. A recording data structure for a data signal recorded on an information recording medium,

A data signal divided into a plurality of frame data (24, 27) each having a predetermined data length,

A timing synchronization signal (23) recorded in the space between adjacent frame data (24, 27);

Instead of a part of the timing synchronization signal (23) or added to at least a part of the timing synchronization signal (23), encryption key information inserted between the frame data (24, 27) is added. Including

A recorded data structure, wherein at least a part of the data signal is converted so as to be recoverable by the encryption key information.

11. The data structure according to claim 10, wherein the data signal is encrypted data that has been encrypted so as to be recoverable with encryption key information.

12. The data structure according to claim 10, wherein the encryption key information is configured by data obtained by cutting a part of the data signal.

13. In an information recording method for recording a data signal on an information recording medium, the data signal is divided into a plurality of frame data (24, 27) each having a predetermined data length,

Encrypting at least a part of at least a part of the frame data (27) to obtain encrypted data;

At least part of the space between adjacent flames (24, 27) Recording the data signal while inserting at least one of a timing synchronization signal (23) and encryption key information (26) for restoring the encrypted data (27). .

14. An information reproducing method for reproducing a data signal recorded by the information recording method according to claim 13.

Reading the encrypted data (2 7) and the encryption key information from the information medium, and restoring the encrypted data (2 7) based on the encryption key information (2 6) based on a predetermined algorithm, An information reproducing method comprising reproducing the data signal.

15. An information recording method for recording a data signal on an information recording medium, comprising: dividing the data signal into a plurality of frame data (24, 27) each having a predetermined data length;

The timing synchronization signal (23) and / or at least one of the ID signals including the ID information of the creator are inserted into at least a part of the space between the adjacent frame data (24, 27). An information recording method characterized by recording a data signal.

16. An information reproducing method for reproducing a data signal recorded by the information recording method according to claim 15.

Reading the data signal and the ID signal from the information medium,

An information reproducing method, wherein the data signal is reproduced when the ID information obtained based on the ID signal matches the stored regular ID information.