JP3169366B1 - Optical disk, optical disk recording apparatus and method, and optical disk reproducing apparatus and method - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To form a first region such as BCA,
Protects the recording film of a recordable optical disk. SOLUTION: An optical disk is formed by irradiating a first region having a region which is formed in a stripe shape in a circumferential direction and has a region where a signal with a reduced reflected light amount is intermittently obtained, and a light beam to a second region. A second area in which the user can record user data is formed. Here, the first region is formed so as to be spaced apart from the second region by a predetermined radial distance. In addition, a lead-in area is formed inside the second area, and the lead-in area includes at least a part of the first area. The second area is preferably a rewritable area or a write-once area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical disk on which data such as AV data (Audio and Visual Data) including copyrighted movie image data and music audio data are recorded, and other recordable optical disks. TECHNICAL FIELD The present invention relates to an optical disk, an optical disk recording device and method, and an optical disk reproducing device and method capable of preventing unauthorized digital copying to a recording medium such as the optical disk.

[0002]

2. Description of the Related Art An optical disk has characteristics that it has better random access than conventional tape media, and that it can perform non-contact recording and reproduction using a laser beam, so that there is little deterioration due to repeated use. are doing. Further, the optical disc has a feature that a large number of copies can be produced at low cost by mastering by a disc manufacturer, and the CD (Co
mpact disks) have become a popular alternative to traditional analog records. Furthermore, in recent years, DVDs (Digital Visible) on which high-quality image data is digitally recorded.
Deo Disk or Digital Versatile Disk) is commercialized, and it is expected that optical disks as digital recording media for AV data will further develop in the future.

On the other hand, music CDs, CD-ROMs and DVD-
In addition to a read-only optical disk in which data is pre-recorded in a pre-pit format by a disk manufacturer, such as a ROM, in recent years, users can record AV data at home, for example, CD-R, CD-RW, MO, MD
Recording-type optical disks such as DVDs and DVD-RAMs have been developed and are spreading worldwide.

[0004] In the television broadcasting, a digital system capable of increasing the number of channels and providing various services from the conventional analog system has been introduced, and such a tendency will be further widened in the future. In particular, a recordable optical disc is used as a recording medium for contents distributed by digitized broadcasting or communication, and is used mainly for time-shifting, which is used for time-shifting, which is stored at the time of distribution and then selected and viewed.
It is expected to be used for data recording.

Conventionally, recording-type optical disks that have been used mainly in computers have been used for the purpose of storing data created by users themselves, and have a mechanism for restricting copying between recording-type optical disks. I didn't.
When recordable optical discs become widely used, ordinary users can illegally copy recorded data from optical discs directly to other recordable optical discs.
Without paying the copyright fee that should be paid to the creator of the AV data, and because digital recording is possible, illegal copies can be obtained without deterioration in sound quality or image quality, and high-quality content can be obtained. Has become a factor that has hindered the spread of the technology. MD for digital recording of music etc.
Has introduced a mechanism for performing generation management for limiting the number of recordings, recording the data on an optical disk together with the generation management data, and limiting the number of copies based on the generation management data.

Further, for example, a CD-ROM or a DVD-R
In order to prevent unauthorized copying of the OM, a burst cutting area (hereinafter referred to as BCA), which is an additional recording area for overwriting a barcode on the pit portion of the optical disc, is provided.
A method of recording a different ID for each disk in CA is
It is proposed in the international application WO 97/14144. According to this method, since the password differs depending on the disk ID, one password can only decrypt the encryption of one disk, and even if the content is illegally copied, the information of the disk ID is missing. The content will not be decrypted.

FIG. 39 is a block diagram showing a configuration of a user data area of a conventional DVD-ROM and a configuration of an optical disc reproducing apparatus for decrypting encrypted content from data in the user data area. In a DVD-ROM, FIG.
As shown in FIG. 9, the content data recorded on the disc is encrypted.

In FIG. 39, the user data area of the DVD-ROM includes a sector header area 3201, a main data area 3202, and an error detection code 3203. Here, in the sector header area 3201, a sector address 3204 indicating the position of the sector, and copyright control information (for example, a scramble flag, copy control information, etc.) on data recorded in the main data area 3202 are recorded. Rights control information 3205 and a decryption key 3206 for decrypting data in the main data area 3202 when the data is encrypted are recorded. In the main data area 3202, AV data mainly requiring copyright protection and the like are encrypted and recorded.

At the time of reproducing the user data area, first, a decryption key 3206 necessary for reproducing the encrypted content is obtained from the sector header area 3201. The obtained decryption key 3206 is input to the key decryption unit 3207, and the key decryption unit 3207 decrypts the input decryption key 3206 using a predetermined disk key to decrypt the content decryption key.
8 is output. Next, the decryptor 3208 decrypts the encrypted content in the main data area 3202 using the decrypted content decryption key according to the copyright control information 3205 stored in the sector header area 3201 corresponding to the main data area 3202. Then, decrypted content that is reproducible data is obtained.

In the optical disk having the configuration shown in FIG. 39, the main data area 3202 can be read from a drive device of a personal computer or the like. By making it impossible to read data, it is possible to prevent unauthorized duplication and creation of pirated copies.

[0011]

However, in an illegal copy prevention method using generation management data, a change in generation management data (a change in information from "copy once" to "non-copyable") during copying is not possible. On the other hand, illegal copying cannot be sufficiently prevented by copying the data on the optical disk together with the generation management data without any change, or by falsifying and recording the generation management data with a computer or the like. There was a problem that.
Furthermore, since the number of copies is limited by the generation management data pre-recorded together with the content, even if a regular copyright fee is paid, data that cannot be copied on an optical disk can be completely copied to another optical disk. However, there is a problem that the user has to wait for the supply from the content supplier. In any case, this is because the content provider cannot sufficiently manage the copying to the recordable optical disc performed by the user.

In recent years, the performance of personal computers has been improved, and these computers have been connected to a network, so that high-performance and high-speed decryption of a plurality of personal computers has been performed. In order to further increase the strength of encryption for such decryption, it is necessary to extend the key length of a key used for encryption. However, in a key management method that records a decryption key in a sector header as conventionally proposed, only a decryption key having a predetermined length (size of a decryption key area) or less can be recorded. There is a problem that the key length cannot be increased in order to increase the strength of encryption in the future.

Further, as described above, a method of providing a BCA and recording a different ID for each disc in the BCA at the time of manufacturing the optical disc is described in International Publication No. WO 97/1414.
No. 4 has been proposed in the international application. This BCA trims the recording film on the concave / convex pits on the inner peripheral portion of the control data area. Has a problem that it is easily affected by heat.

An object of the present invention is to solve the above problems,
An optical disc capable of protecting a recording film of a recordable optical disc when forming a first area such as a BCA;
An object of the present invention is to provide an optical disk recording device and method, and an optical disk reproducing device and method.

[0015]

According to the present invention, there is provided an optical disk comprising: a first region which is formed in a stripe shape in a circumferential direction and has a region where a signal having a reduced reflected light amount is intermittently obtained; An optical disc having a second area in which a user can record user data by irradiating the second area with the second area, wherein the first area has a predetermined radial distance from the second area; Are formed so as to be separated from each other.

Further, in the above-mentioned optical disk, preferably, there is provided a lead-in area formed inside the second area, and the lead-in area includes at least a part of the first area. . Further, in the optical disc, the second area is preferably a rewritable area or a write-once area.

An optical disc recording apparatus according to the present invention is an optical disc recording apparatus comprising: a predetermined first area; and a second area in which a user can record user data by irradiating a second area with a light beam. An optical disc recording device for forming data such that a signal whose reflected light amount is reduced intermittently at the time of reproduction is formed in a stripe shape in the circumferential direction,
And a recording means for recording in a first area separated from the second area by a predetermined radial distance.

Further, in the optical disk recording method according to the present invention, a predetermined first area and a second area in which a user can record user data by irradiating a light beam to the second area.
An optical disk recording method for an optical disk having an area of the second type, wherein data for intermittently obtaining a signal whose reflected light amount is reduced at the time of reproduction is formed in a circumferential stripe shape, and The method is characterized in that it includes a step of recording in a first area separated from the area by a predetermined radial distance.

Further, in the optical disk reproducing apparatus according to the present invention, data such that a signal whose reflected light amount is reduced at the time of reproduction is intermittently formed is formed in a stripe shape in the circumferential direction.
In addition, by irradiating the first area recorded on the first area with a predetermined distance in the radial direction with respect to the second area and the second area, the user data is generated by the user. An optical disc reproducing apparatus for an optical disc having a recorded second area, comprising: first reproducing means for reproducing data recorded in the first area; and an optical disc reproducing apparatus for reproducing data recorded in the second area. And second reproducing means for reproducing the user data.

Still further, in the optical disk reproducing method according to the present invention, data such that a signal whose reflected light amount is reduced at the time of reproduction is intermittently formed is formed in a stripe shape in the circumferential direction, and A first area recorded in a first area separated by a predetermined distance in a radial direction, and a second area in which user data is recorded by a user by irradiating a second area with a light beam. An optical disc reproducing method for an optical disc, comprising: reproducing data recorded in the first area; and reproducing user data recorded in the second area. It is characterized by.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

<First Embodiment> FIG. 1 is a plan view showing a data recording area of a recordable optical disc 100 according to a first embodiment of the present invention. This recordable optical disk 1
Reference numeral 00 denotes a recording medium on which digital data can be recorded, and includes a write-once optical disc and a rewritable optical disc.

In FIG. 1, reference numeral 101 denotes an optical disc 100.
A management area 102 is a lead-in area. Reference numeral 102 denotes content of AV data including at least one of image data (including still images and moving images) such as a movie and audio data such as music, and computer software. A user data area 103 in which digital data requiring copyright protection is recorded, and a lead-out area 103 in which defect management information and the like are recorded. The lead-in area 101 includes a read-only area 104 recorded in the form of pre-pits, and a recording / reproducing area 105 which is a rewritable area having a guide groove. Here, in the read-only area 104, a control area or the like describing physical characteristics of the optical disc 100 is recorded in a pre-pit format by a manufacturer. In the lead-out area 103 and the rewritable area 105,
Data for a write test by the optical disk recording device, management information for managing defects on the optical disk 100, and the like are recorded by the optical disk recording device. Further, on the inner peripheral side of the read-only area 104 of the lead-in area 101, the BCA 106 as disc individual information is written on the optical disc 100 after the optical disc 100 on which the content is recorded is completed by a known method as described below. It is added.

FIG. 2 (a) shows the optical disk 100 of FIG.
FIG. 2B is a block diagram and a longitudinal sectional view showing an apparatus configuration when the CA 106 is formed. FIG.
7A and 7B are a longitudinal sectional view of the optical disc 100 after the BCA 106 of No. 00 is formed and a graph showing the intensity of reflected light in the horizontal direction. 2A and 2B show an example of a double-sided recording type optical disc 100. The optical disc 100 has a recording layer 2 between two substrates 201 and 207.
02, a reflective layer 203, an adhesive layer 204, a reflective layer 205, and a recording layer 206.

When recording the BCA on the optical disc 100, as shown in FIG. 2A, a laser beam from a high-power laser light source 211 is pulsed to a reflection layer 205 of the optical disc 100 via a focus lens 212, for example. By removing the reflective layer 205 by irradiating in the form of stripes, stripe-shaped data subjected to phase encoding modulation is recorded so as to overlap the pits. At the time of reproduction, as shown in FIG. 2B, a signal in which the amount of reflected light is reduced is intermittently reproduced in a portion where the reflection layer 205 is removed, and the reproduced signal is binarized and then phase-encoded. The BCA data is reproduced by demodulation (phase encoding demodulation). The BCA created by such a recording method has a feature that a disc identifier, which is information unique to each optical disc 100, can be recorded, and that it cannot be falsified.

FIG. 3 is a diagram showing a recording format of the BCA 106 shown in FIG. As shown in FIG.
6, a synchronization code 301, an error detection code 302,
An error correction code 303 and the like are recorded to improve the reading rate of the BCA data 304. The disc identification information 305 is configured by linking the plurality of BCA data 304. Disk identification information 305
In the field, the type of data that can be recorded in the user data area and the type of data that can be reproduced from the user data area are recorded. Since the data of the BCA 106 cannot be falsified, a certain restriction can be imposed on the user's use of the disc by disc identification information recorded when the optical disc 100 is manufactured.

FIG. 4 is a diagram showing a sector structure of the sector data 401 in the user data area 102 of FIG. In FIG. 4, the user data area 102 of FIG. 1 has a sector structure that can be accessed in a fixed amount unit.
03, an error detection code 404.

Here, the main data 403 is an area in which AV data, computer data, and the like are recorded. The header 402 includes a data ID (Data Identifier).
405), ID error detection code 406, scramble control information 407, key information 408, and the like. In the data ID 405, a logical address or the like for identifying a sector is recorded.
Reference numeral 6 denotes a code for detecting an error in the data ID.
The scramble control information 407 is a flag indicating whether or not the main data has been scrambled, and the key information 408 records information on a key for descrambling the main data. As information on the key, the descrambling key itself (a modification of the first embodiment) and a key index (first embodiment) which is a pointer to a descrambling key recorded in another area on the optical disc 100 are recorded. Is done. The example of FIG. 4 shows a case where a key index for referring to the descramble key recorded in the key management information area 107 of FIG. 1 which is another area on the optical disc 100 is recorded.

FIG. 5 is a diagram showing the configuration of the key management information area 107 of FIG. In FIG. 5, a key management information area 107 includes a key information area 501, a content information area 502, and a key index list area 503.

In the key information area 501, the number 504 of used descrambling key areas is recorded.
The key information area 501 includes a descramble key area 505 for recording a descramble key for descrambling the AV data or the like, and a recording state of the descramble key recorded in the descramble key area 505 ( Key status area 506 for recording unused, area reserved, recorded, etc.). A plurality of descrambling keys are recorded in the descrambling key area 505, a key index indicating a storage position in the descrambling key area 505 is recorded in a key index list area 503, and the plurality of descrambling keys are stored in the key index. Can be referred to by In the key status area 506, status information indicating the recording state of the previous descramble key is stored at a position that can be referred to by the key index.

In the content information area 502, of the contents recorded on the optical disc 100, those requiring copyright protection are registered, and information on keys used in the contents is also registered. In the content information area 502, the number of contents 507 registered in the key index list area 503 and the content information 508 for the number of contents are recorded. Further, in the content information 508, a content ID for identifying the content, the number of descrambling keys used in the content, and a pointer to a key index list 509 in which the used keys are recorded are recorded. The key index list area 503 is an area for recording an index for referring to a key used in content in a list format in content units. In the key index list area 503, a key index that refers to a recording area of all descrambling keys used in the content is recorded.

The recording type optical disk 1 thus configured
In the case of 00, an area identifier, a data category identifier, a disk identifier, and the like are recorded at the time of manufacture as information indicating the use condition of the disk in the disk identification information that is difficult to rewrite, and the optical disk recording / reproducing apparatus detects such information. In addition, it is possible to control the recording operation and the reproduction operation according to the copyright protection level and usage level of the content. Also, since the data is recorded by a method that is difficult to rewrite and cannot be changed by the user, even if the copyrighted content is copied to another optical disk, the user data area can be copied,
Disk identification information cannot be copied. Therefore, by recording the data scrambled using the disc identification information on the optical disc, there is a user data area that cannot be descrambled on an optical disc having different disc identification information, and correct reproduction cannot be performed.

FIG. 15A shows whether contents can be copied or reproduced in the same region and in different regions when the region identifier is recorded at the time of recording contents in the first embodiment. FIG. 15 is a diagram showing
(B) shows whether contents can be copied or reproduced within the same region and in different regions when the region identifier is recorded in advance at the time of shipment of the optical disc in the first embodiment. FIG.

For example, as shown in FIG. 15A, when the optical disc is shipped, no area identification code is recorded,
When the area identifier indicating the area where the content is available is recorded in the recording and playback area when the content is recorded,
Use in other areas can be prevented. However, a disc to be used in another area (area RC2 in FIG. 15A)
), The content can be recorded, and the content can be correctly reproduced. Recording media capable of digital copying of content are provided with a levy system or the like in order to protect the interests of the copyright holder, and are collected at an additional fee when the optical disk is sold. However, the added levy differs from country to country, so if a recording medium to be used in another country is used improperly, it may not be correctly allocated to copyright holders who should originally benefit.

Further, as shown in FIG. 15B, by recording the area identifier in advance by a method that cannot be falsified when the optical disk is shipped, copying or reproducing the content to the optical disk to be used in another area. Can be prevented. Similarly, when the data category identifier is recorded as disc identification information, by copying the data category identifier with the category identifier of the data to be recorded, it is possible to restrict copying and reproduction of the content to and from a disc capable of recording and reproducing data. When a disc identifier unique to each optical disc is recorded as disc identification information, data to be recorded can be encrypted only with the disc identifier and used only on that optical disc.

In the present embodiment, the data scrambled by the disc identification information may be AV data or computer data requiring copyright protection, or descrambling for descrambling the AV data or computer data. It may be a key.

FIG. 13 is a block diagram showing a method for determining whether or not an encrypted descramble key is a valid descramble key according to a modification of the first embodiment. As shown in FIG. 13, an encrypted descramble key calculated by scrambling data obtained by adding an error detection code for detecting an error of the descramble key to the descramble key using the disc identification information is used as an optical disc. May be recorded. The optical disc playback device decodes the encrypted descrambling key into a descrambling key and an error detection code, and detects an error based on a parity check or the like in the decoded error detection code. It is determined whether or not it is. For example, if descrambling is performed using different disc identification information, an erroneous descrambling key is generated, and by checking the error detection code, it can be determined that the key is not a legitimate descrambling key. it can.

As another method of recording disc identification information, a plurality of types of disc identification information are prepared by using stampers prepared by pre-pits, and an optical disc is prepared from each of the stampers. Restrictions may be given.
Furthermore, by scrambling the disc identification information using a secret key and recording the scrambled disc identification information on the optical disc, the user does not know the copyright protection level described in the disc identification information, As a result, copyright protection is further enhanced.

When the descramble key itself is recorded as the information on the key described in FIG.
FIG. 6 shows a modification of the first embodiment) and a case where a key index which is a pointer to a descramble key recorded in another area on the disk is recorded (first embodiment).
This will be described with reference to FIG. Here, FIG. 6A is a block diagram showing a recording method for recording a descramble key and AV data in the sector data 401 of FIG. 1 according to a modification of the first embodiment, and FIG.
FIG. 3 is a block diagram showing a recording method for recording a key index to a descramble key and AV data in the sector data 401 of FIG. 1 according to the first embodiment.

In the case of FIG. 6A, the main data 403 and the key information 4 necessary for descrambling the main data 403 are stored in the same sector data 401.
The descrambling key 08a is recorded. For this reason, when recording AV data, it is necessary to obtain a descrambling key necessary for descrambling. That is, it is indispensable to obtain or purchase the key itself when recording AV data.

On the other hand, in the case of FIG. 6B, in the same sector data 401, main data 403 and key information for referring to a descrambling key area for recording information necessary for descrambling the main data 403 are shown. 408
Is recorded, and a descramble key is recorded in an area specified by the key index.
At the time of recording AV data, a key ID indicating which of the keys used in the content to be recorded can be descrambled is obtained, and a key index corresponding to the key ID is obtained from a key index list included in the content information. Is acquired and recorded together with the main data 403. The descrambling key is recorded when the descrambling key is obtained, and is recorded in the descrambling key area indicated by the key index corresponding to the key ID. As a result, recording of the AV data and the descrambling key corresponding thereto can be performed independently. That is, recording of AV data and acquisition or purchase of a key can be performed independently, and acquisition or purchase of a key is not necessarily required when recording AV data.
The user can record the content and obtain a key when actually reproducing the content.

FIG. 14 is a diagram showing a configuration of a descrambling area management table according to a modification of the first embodiment. In the above embodiment, a case has been described where a key index for referencing a descramble key is recorded in the same sector data 401 in order to associate the encrypted content with the descramble key for decrypting the encrypted content. Alternatively, the descrambling area management table of FIG. 14 for managing the correspondence between the address range of the sector in which the encrypted content is recorded and the descrambling key may be used. In this descrambling area management table, the address range of the sector in which the encrypted content is recorded is represented by a start address and an end address. When reproducing data in those sectors, the descrambling key is referred to, Descramble the encrypted content.

In order to obtain the content to be recorded and the descrambling key used therein, a content ID that allows the content to be identified is used. The content information area 50 recorded on the optical disc as shown in FIG.
2 is recorded as a list of a content ID and a descrambling key used for the content in the content information recorded in the content management list in 2. By adopting a list structure in which a plurality of descrambling keys can be used for one content, a service of selling a part of the content or software can be realized.

In the modification described above with reference to FIG. 13, data obtained by scrambling a descrambling key to which an error detection code such as a checksum or a cyclic redundancy check code is added with disk identification information is transferred to another disk. In the case of illegal copying, an error is detected by performing descrambling with different disk identification information. In such a case, it is possible to obtain a descramble key scrambled by the disc identification information recorded on the optical disc and obtain a descramble key, and replace it with the descramble key to create a disc that can be correctly reproduced.

The key management information area 107 shown in FIG. 1 is recorded in the rewritable lead-in area 101. Normally, the user data area 102 includes a user area accessible from a drive device of a personal computer and a spare area for a defective sector on an optical disk. In a normal read command or write command, only the user area is a logical continuous area. Is accessible as By arranging key management information in the lead-in area 101, it is possible to prevent direct access from a drive device of a personal computer, and to obtain a key for descrambling AV data or the like from a personal computer. It can be.

<Second Embodiment> FIG. 7 is a block diagram showing the configuration of an optical disk recording / reproducing apparatus according to a second embodiment of the present invention. This optical disk recording / reproducing apparatus is an apparatus that records AV data contents such as image data and music data requiring copyright protection on the optical disk 100 according to the first embodiment.

In FIG. 7, reference numeral 701 denotes the optical disk of the first embodiment, 702 denotes an optical head which is an optical pickup composed of a semiconductor laser and an optical element, and 703 controls the operation of the semiconductor laser and binarizes a reproduction signal. A recording / reproducing control circuit 704; a modulation / demodulation circuit 704 for digitally modulating digital data to be recorded and digitally demodulating a binarized reproduction signal; and 705, an error detection and error detection function for errors caused by scratches and dust on the optical disk 701. An error detection and correction circuit that performs a correction process and a process of generating an error correction code required for the error detection and correction process; 706, a buffer memory that is a RAM used as a working memory and a data buffer memory of the error detection and correction circuit 705; 70
Reference numeral 7 denotes a descrambling circuit for descrambling AV data recorded scrambled and recorded, 708 an MPEG decoding circuit for expanding compressed moving image data and the like, and 709 D / A conversion of the expanded image data. An output circuit for generating and outputting a video signal and an audio signal, and 710, a control CPU for controlling the operation of the entire optical disk recording / reproducing apparatus; 711, a communication circuit for obtaining a descramble key for decrypting the content applied to the content; A data receiving circuit receives digital data of encrypted contents such as image data and music data from a communication terminal device such as a set-top box.

The data recording operation in the optical disk recording / reproducing apparatus of FIG. 7 configured as described above will be described. Digital data of encrypted content such as image data and music data transmitted from a communication terminal device such as a set-top box or an MPEG encoder is temporarily stored in a buffer memory 706 after being received by a data receiving circuit 712. Is done. An error detection and correction circuit 705 generates error detection and correction codes necessary for error detection and correction processing due to scratches or dust on the optical disc 701 in the stored digital data of the content, and reconstructs the recorded data. I do. A code such as a known Reed-Solomon code is used for the error detection and correction code. Here, the reconstructed recording data includes digital data of the content and an error detection and correction code. The modulation / demodulation circuit 704 digitally modulates recording data using a modulation method such as an 8/16 modulation method at the time of recording. The recording / reproduction control circuit 703 modulates the intensity of the laser beam output from the optical head 702 in accordance with the digitally modulated recording data, and irradiates the laser beam to the optical disk 701, thereby converting the recording data to the optical disk 701. Record above.

FIG. 8 is a flowchart showing a process of recording AV data executed by the control CPU 710 of the optical disk recording / reproducing apparatus shown in FIG.

In FIG. 8, first, in step S801, the disc identification information in the lead-in area 101 is reproduced before recording the AV data from the optical disc 701, and then, in step S802, the disc identification information is recorded. It is determined from the type of data that can be recorded in the user data area 102 whether or not the digital data of the content to be recorded is recordable. If YES in step S802, the process proceeds to step S803, while if NO, step S81.
At 0, the recording operation is stopped and the recording process of the AV data is terminated.

In step S803, the lead-in area 1
In step S804, it is determined whether or not an area for key information necessary for recording content has been allocated to the reproduced key management information in step S804. Step S80
If NO in step S4, an area for recording key information is assigned to the key management information area 107, and then step S
Proceed to 806. On the other hand, if “YES” in the step S804, the process directly proceeds to the step S806.

When recording the content, the control CPU 710 of the optical disk recording / reproducing apparatus receives the data of the encrypted content to be recorded and the information on the descrambling key for decrypting the data from the communication terminal device. Receive via circuit 712. Here, the key information is the key itself used in the content,
Alternatively, it is a key ID indicating which key of the keys used in the entire content corresponds to. Key ID
Is received, in step S806, the received key ID is converted into a key index which is a pointer indicating an area where a descrambling key corresponding to the key ID is recorded, and the converted descrambling key is It is arranged in the header area of the sector in which the data of the content to be decrypted with the descramble key is recorded. And
In step S807, the control CPU 710 executes the following recording data processing by controlling the recording / reproduction control circuit 703, the modulation / demodulation circuit 704, and the error detection and correction circuit 705. In this processing, codes for error detection and correction are added to the sector data to be recorded, and the sector data to which these codes have been added is digitally modulated using a known modulation system such as an 8/16 modulation system. The optical head 702 is controlled to a predetermined recording position, and the intensity of the laser beam is modulated according to the digitally modulated recording data. Thus, the recording data is recorded on the optical disk 701. Further, step S808
Now, determine whether the recording of the content is over,
If NO, the process returns to step S806, and the above processing is repeated. If “YES” in the step S808, the updated key management information is recorded in the key management information area 107 on the optical disc 701 and the AV
The data recording process ends.

FIG. 9 is a flowchart showing a key management information area allocation process executed by the control CPU 710 of the optical disk recording / reproducing apparatus of FIG. This process is a process of allocating an area for recording a descrambling key before recording content data.

In FIG. 9, first, in step S901, information on the key of the content to be recorded (including the number of descramble keys to be used) is acquired from, for example, an electronic program guide, and then, in step S902, the optical disk The key management information in the key management information area 107 recorded in the key management information area 701 is reproduced. Determine whether the key can be recorded. If “NO” in the step S903, the recording operation is stopped in a step S907, and the assignment processing is ended. On the other hand, step S9
If YES in step 03, the content to be recorded is registered in the content list in the content information area 502 in step S904, and an area necessary for recording the descramble key is stored in the descramble key area 505 in step S905. To make a reservation, a recording area is allocated by setting an area reserved flag in the corresponding key status area. Further, step S906
Then, a key index indicating an area allocated for recording the descrambling key is created as a key list, and after assigning a pointer as content information,
The allocation process ends.

FIG. 10 is a flowchart showing a descrambling key recording process executed by the control CPU 710 of the optical disk recording / reproducing apparatus of FIG. This recording process is a process for acquiring a descramble key from the key management center and recording the same on the optical disc 701.

In FIG. 10, first, at step S100
1, the lead-in area 101 of the optical disc 701
After reproducing the disc identification information of step S1002,
In order to obtain a descrambling key from the key management center, the disk identification information and the key ID for identifying the key required for descrambling the desired content are transmitted to the key management center via the communication circuit 711. . The key management center selects a descrambling key required for descrambling the content from the given key ID, encrypts the descrambling key according to the transmitted information such as disc identification information, and returns the encrypted descrambling key.

In step S1003, the descrambling key corresponding to the key ID is obtained from the key management center via the communication circuit 711.
The data in the key management information area 107 is reproduced, and a key index indicating the area in which the descramble key is recorded is obtained from the key index list indicated by the key ID among the data in the reproduced key management information area 107.
Next, in step S1005, the obtained descrambling key is arranged in the descrambling key area indicated by the key index, and the obtained flag indicating that the key has been obtained is set in the corresponding key status area 506. Further, in step S1006, it is determined whether acquisition of all keys has been completed. If NO, the process returns to step S1003 and repeats the above processing. on the other hand,
If YES in step S1006, step S1006
In step 1007, the updated key management information is recorded in the key management information area 107, and the recording process of the descramble key ends.

Next, a data reproducing operation of the optical disk recording / reproducing apparatus of this embodiment will be described with reference to FIG. The digital data recorded on the optical disc 701 is reproduced as follows. Laser light from the semiconductor laser of the optical head 702 is applied to the optical disk 701, and at that time, the reflected light reflected by the optical disk 701 enters the recording / reproduction control circuit 703 via the optical head 702. The recording / reproducing control circuit 703 performs amplifying and binarizing processing after photoelectrically converting the incident reflected light, thereby generating a digitized reproduced signal and outputting it to the modem circuit 704. The modulation / demodulation circuit 704 digitally demodulates a digitally modulated signal into a digital signal using a known modulation method such as an 8/16 modulation method at the time of recording, and outputs the digital signal to an error detection and correction circuit 705. Then
The error detection and correction circuit 705 includes a buffer memory 706
Is used as a working memory to detect and correct errors caused by scratches or dust on the optical disc 701. The error detection and correction processing is executed by decoding a known Reed-Solomon code, for example.

The reproduced data subjected to the error detection and correction processing is output to a descrambling circuit 707 for descrambling processing. Descramble circuit 707
Performs descramble processing on the reproduced data using the descrambling key in the key management information area 107 reproduced in advance prior to the data reproduction, and then executes the MPEG decoding circuit 70
8 is output. Next, the MPEG decoding circuit 708 expands the compressed moving image data and music data, and outputs the expanded data to the output circuit 709. Further, the output circuit 709 performs D / A conversion of the input decompressed data into a video signal and an audio signal, and outputs the converted signal to a higher-level device such as a television device or an audio device.

FIG. 11 is a flowchart showing the AV data reproducing process executed by the control CPU 710 of the optical disk recording / reproducing apparatus shown in FIG. In FIG.
First, in step S1101, the optical disk 701
Prior to recording of AV data from the
1 is reproduced, and step S1102 is performed.
, It is determined from the type of reproducible data recorded in the disc identification information whether or not the content currently being reproduced is reproducible. Step S1
If NO in step 102, the reproduction operation is stopped in step S1112, and the reproduction process of the AV data is terminated.
On the other hand, if YES is determined in the step S1102, in a step S1103, the data of the sector in which the key management information is recorded in the key management information area 107 of the lead-in area 101 is reproduced, and in the key management information reproduced in the step S1104, Then, it is determined whether or not key information necessary for reproducing the content has been recorded. Step S11
If YES in step 04, step S1106 is performed as it is.
On the other hand, if NO, in step S1105, a descrambling key is obtained from the key management center managing the key via the communication circuit 711, and recorded in the key management information area 107 of the optical disc 701, and then the process proceeds to step S1106. Proceed to.

Next, in step S1106, control C
The PU 710 moves the optical head 702 to the user data area of the optical disc 701,
It controls the modulation / demodulation circuit 704 and the error detection / correction circuit 705 to reproduce AV data. Then, step S110
7, a descrambling key area 505 indicated by a key index included in the header of the reproduced sector.
, A descrambling key necessary for descrambling the sector data is obtained, and in step S1108, the scramble performed on the descrambling key is decrypted by descrambling using the disc identification information. Further, in step S1108, by checking the error detection code assigned to the descramble key, it is determined whether or not the descramble key has an error. If YES is determined in step S1108, the content is regarded as illegally obtained content (or illegally copied content), and in step S1112, the reproduction operation is stopped, and the reproduction process of the AV data is ended.

On the other hand, if NO in step S1108, in step S1109, the content data is descrambled using the descrambling key.
At 110, the descrambled AV data is
Output to the PEG decoding circuit 708. And the control CPU
Reference numeral 710 denotes an MPEG decoding circuit 708 and an output circuit 709.
, The D / A conversion of the descrambled AV data into a video signal and an audio signal is performed, and the resultant data is output to a higher-level device such as a television device or an audio device. Next, step S1111
Then, it is determined whether or not the reproduction of the content has ended.
If it is, the process returns to step S1106, and the above processing is repeated. On the other hand, if YES in step S1111, the reproduction process of the AV data is terminated.

If an error is detected in step S1109, the content is regarded as illegally obtained content. For example, it is regarded as illegally copied content, and the reproduction operation is stopped. Similarly,
By executing the processing in step S1105, key information may be obtained from the key management center that manages the keys via the communication circuit 711, and may be recorded in the key management information area 107 of the optical disc 701. This makes it possible to reproduce even the copied AV data by obtaining the key properly.

FIG. 12 is a flow chart showing a descrambling key acquisition process executed by the control CPU 710 of the optical disk recording / reproducing apparatus of FIG. This process is a process of reproducing the descramble key from the reproduced key index, and is executed prior to the AV data reproduction process shown in FIG.

In FIG. 12, first, at step S120
In step 1, whether or not the reproduced data in the sector area is scrambled is determined based on the scramble control information, and if NO, the process proceeds to step S1206.
If YES, in step S1202, a key index is obtained by reproducing key information recorded in the same sector area as the sector area,
Next, after acquiring the descrambling key indicated by the key index from the descrambling key area 505 in step S1203, step S120
In step 4, the obtained descrambling key is descrambled using the disc identification information, and an error detection code is checked to determine whether or not the descrambling key has an error. If YES in step S1204, the reproduction operation is stopped in step S1205, and the descramble key acquisition process ends. On the other hand, step S12
If the answer is NO in 04, the process proceeds to step S1206.
If the reproduced sector has not been scrambled, or if the result of descrambling the descrambling key with the disc identification information has no error, step S1 is executed.
At 206, the reproduction operation is permitted, the data of the reproduced sector is output, and the process of obtaining the descramble key ends.

As described above, in the optical disk and the optical disk recording / reproducing apparatus according to the embodiment of the present invention, the recording and reproducing operations by the user are controlled by using the reproduction-only disk identification information created in the disk manufacturing stage. it can. Further, by scrambling a part of the data using the above-mentioned disc identification information, it is possible to prevent normal reproduction from the disc on which the user data area has been physically copied. Further, by arranging the descrambling key necessary for descrambling the data in an area different from the data, it is possible to record the content and the descrambling key independently. For this reason,
The content can be recorded, and if necessary, for example, when the content data is reproduced, a descrambling key can be acquired to make the content reproducible. At this time, it is obvious that, by scrambling the descrambling key using the disc identification information, illegal use by physical copying can be prevented as in the case described above. In addition, even if the disc is illegally copied, the descramble key scrambled with the disc identification information of the optical disc is officially obtained from the key management center and recorded on the optical disc to make the optical disc playable correctly. You can also.

Although the content data inputted to the optical disk recording / reproducing apparatus has already been described as being encrypted, the provision of a circuit for encrypting the content in the optical disk recording / reproducing apparatus allows the input content to be encrypted. The same effect can be obtained by encrypting data and recording it on an optical disk.

Further, in the present embodiment, only descrambling keys necessary for decrypting the encrypted contents are encrypted using the disk identification information, thereby preventing copying between disks having different disk identification information. However, by encrypting the content itself using the disc identification information, the copy can be similarly prevented. Furthermore, by encrypting the disc identification information using the secret key, it is possible to make it more difficult to illegally decrypt the content recorded on the disc.

<Effects of the First and Second Embodiments> The optical disc of the embodiment according to the present invention performs a recording operation and a reproducing operation on a user data area for each optical disc. By being recorded in the area, it is possible to control the recording operation and the reproducing operation of the content on the optical disk by the user using the information recorded at the time of manufacturing the optical disk.

In the optical disk according to the embodiment of the present invention, the encrypted data is recorded in the user data area on the optical disk by using the non-rewritable, read-only disk identification information as a key. Even if the data is copied to another recordable optical disk in the area, the disk identification information cannot be copied, and correct decoding and reproduction of data can be disabled.

In the optical disk according to the embodiment of the present invention, the encrypted data and the descrambling key for decrypting the encrypted data are recorded in different sector areas, so that the data such as a movie or music that needs copyright protection is protected. Acquisition and acquisition of a descrambling key for decryption can be performed independently. Further, by encrypting and recording the descramble key using the disc identification information as a key, even if the user copies the disc data to another recordable optical disc in the user data area, the disc identification information cannot be copied. It is impossible to correctly decrypt and reproduce the data, and by acquiring and recording the descramble key encrypted using the disc identification information of the copy destination optical disk as a key, it is possible to correctly decrypt and reproduce the data.

<Third Embodiment> Next, a method for recording and reproducing encrypted content according to a third embodiment of the present invention will be described with reference to the drawings. FIG. 16 is a plan view showing a data recording area of an optical disc 1101 according to the third embodiment of the present invention.

In FIG. 16, reference numeral 1101 denotes a recording medium on which digital data can be recorded, which is a recordable optical disc which is a rewritable or write-once optical disc;
Reference numeral 1102 denotes a control user data area in which disc information is recorded in the form of minute concave and convex pits; 1103, a user data area in which a user records data by irradiating the optical disc with a laser beam; and 1104, a disc ID is recorded. BCA. BCA110
In 4, the recording film on the minute uneven pits in the inner peripheral portion of the control user data area 1102 has a shape that is long in the radial direction and is partially formed with respect to the recording film so that a plurality of trimming areas 1105 are formed. The trimming is performed by radiating a laser beam of a pulse laser such as a YAG laser or the like, whereby a disc ID as descrambling identification information is recorded.

FIG. 17 is a waveform diagram showing the signal waveforms of the reproduced signal 1201 and the reproduced binary signal 1207 in the BCA reproducing circuit 1401 according to the third embodiment.
FIG. 17 is a block diagram illustrating a configuration of a BCA reproduction circuit 1401 according to the third embodiment. In FIG. 17, BCA1
10 shows a reproduced signal 1201 when the data of 104 is reproduced. In FIG. 18, 1301 is an optical pickup, 1302 is a preamplifier, 1303 is a low-pass filter (LPF), 1304 is a binarization circuit, and 1305 is a demodulation circuit.

In FIG. 18, an optical pickup 1301
Is output from the BCA of the optical disk 1101
1104, and the reflected light is
After the photoelectric conversion by 1, the electrical signal after the photoelectric conversion is
The reproduced signal 1201 is obtained by being amplified by the preamplifier 1302. Here, the reproduced signal 1201 in FIG. 17 is a signal having a level corresponding to the concave and convex pits in the control user data area 1102. In the reproduced signal 1201, 1202, 1203 and 1204 are obtained by removing the recording film by a trimming process using a pulse laser. This is a trimmed portion where the signal due to the uneven pits is missing.
This trimming process is performed by the manufacturer of the optical disk.

Referring back to FIG. 18, the reproduction signal 120
1 is input to the low-pass filter 1303, and after the modulation signal due to the uneven pit is removed, the binarization circuit 130
4 is input. The reproduction signal input to the binarization circuit 1304 is not a normal slice level 1205 for binarizing the signal of the control user data area 1102,
It is binarized using a slice level 1206 which is a level sufficiently lower than the slice level 1205, and reproduced 2
A value signal 1207 is obtained. The reproduced binarized signal 1207 output from the binarization circuit 1304 is
5, and a disk ID signal 1306 is obtained.

As described above, the management of the optical disk can be easily realized by adding the disk identification information for identifying the optical disk. Also, BCA1
104 is recorded on the uneven pits,
It is possible to prevent the information for identifying the optical disk in 1104 from being easily falsified. Further, the control user data area 1102 and the BCA 110 of FIG.
4 are adjacent to each other, when the data in the control user data area 1102 is reproduced, the BCA 110
4 can also be played back continuously, or BC
When the data of A1104 is reproduced, the data of the control user data area 1102 can be reproduced continuously. For example, when starting the optical disk, the CPU obtains information of the BCA 1104 for quickly identifying the optical disk, This makes it possible to expedite the process for recording the encrypted content.

The BCA 1104 of this embodiment is formed by trimming the recording film on the concave and convex pits in the inner peripheral portion of the control user data area 1102. The recording film constituting the optical disk is easily affected by heat with respect to the reflection film of the read-only optical disk. By trimming the inner peripheral part of the control user data area 1102, the user data area 1103 can be protected from the heat generated at the time of trimming as compared with the case of trimming the outer peripheral part. Also,
BC on the inner side of the control user data area 1102
The reason why A1104 is formed is that a margin when the diameter of the spot of the laser beam changes due to instability of the focus servo circuit is taken into consideration.

The data recorded in the BCA 1104 before trimming may be recorded in the control user data area 1102. Since the data recorded in the BCA 1104 is also recorded in the control user data area 1102, the data in the control user data area 1102 can be protected even if trimming is performed. In addition, BCA110
4 is continuously and repeatedly recorded from the BCA 1104 to the control user data area 1102, by finding the data in the control user data area 1102,
The location of the BCA 1104 can be predicted.

Next, the disk I1 having the BCA 1104 is connected to the disk I1 via a network.
A procedure for recording the content encrypted by D will be described.
In the third to fifth embodiments, the network is
For example, it refers to a communication network such as the Internet, a public telephone line, or a dedicated line. FIG. 19 is a block diagram showing the configuration of an optical disk recording / reproducing system according to the third embodiment. The device configuration for recording encrypted content on a recordable optical disk 1101 which is a rewritable or write-once optical disk having the BCA 1104 is described. Is shown.

In FIG. 19, the optical disk recording / reproducing system is connected to a network 14 such as the Internet.
Optical disk recording / reproducing device 14 connected via
10 and an encryption unit 1406. The optical disk recording / reproducing device 1410 includes an optical pickup 130
1, the BCA reproduction circuit 1401, and the Internet 40
3, a recording circuit 1411, a data reproducing unit 1412,
And an encryption decoder 1413. Also, the encryption unit 14
06 includes an interface 1404, a content memory 1407, and an encryption encoder 1408.

First, the laser beam output from the optical pickup 1301 irradiates, for example, the BCA 1104 of the RAM type optical disk 1101, and the reflected light is photoelectrically converted by the optical pickup 1301, and the reproduced signal obtained by the photoelectric conversion is subjected to BCA reproduction. The signal is input to the circuit 1401. BCA
The reproduction circuit 1401 performs BC based on the input reproduction signal.
A, reproduces the disk ID signal 1402 in A, outputs the reproduced disk ID signal 1402 to the encryption decoder 1413, and
04 and the network 1405, the encryption unit 140
6 to the encryption encoder 1408. The encryption encoder 1408 encrypts the content data so that the disk ID signal 1402 of the optical disk 1101 on which the content data in the content memory 1407 is recorded becomes a decryption key for decryption, or scrambles the video and audio. I do.

In the present embodiment, in the encryption processing, the contents 1407 are stored in the disk ID signal 1402.
It is the same meaning to express that encryption is performed by using as an encryption key. In the present embodiment, encryption and decryption are considered in the relationship between a lock and a key. Closing the lock with the key is referred to as encryption, and opening the lock with the key is referred to as decryption. Therefore, it is assumed that the actual operation differs between encryption and decryption, but the key for encryption and the key for decryption are the same. Note that the content 1407 is C, the disc ID signal 1402 is BCAS, the encrypted content 1409 is C [BCAS], and the operation of the encryption process is represented by *, and is represented by the following equation.

[0084]

## EQU1 ## C * BCAS = C [BCAS]

The content 1409 encrypted by the encryption unit 1406 is transmitted to the interfaces 1403 and 1
Recording / reproducing apparatus 1 via the network 404 and the network 1405
It is sent to the recording circuit 1411 of 410. Recording circuit 141
1 performs predetermined digital modulation of input content data, and intensity-modulates a laser beam from an optical pickup 1301 according to the digitally modulated data to irradiate the optical disk 1101 with the content data, thereby converting the content data to the optical disk 1101. To record.

Next, when reproducing the above-mentioned contents encrypted and recorded on the optical disk 1101, the laser beam output from the optical pickup 1301 irradiates the area of the user data area 1103 where the above-mentioned encrypted contents are recorded. Then, after the reflected light is photoelectrically converted by the optical pickup 1301, the reproduced signal subjected to the photoelectric conversion is input to the data reproducing unit 1412. The data reproduction unit 1412
The input reproduction signal is A / D converted to digital data and output to the encryption decoder 1413. On the other hand, the laser beam from the optical pickup 1301
Irradiate CA1104, and the reflected light
After the photoelectric conversion by 301, the photoelectrically converted reproduction signal is input to the BCA reproduction circuit 1401. The BCA reproduction circuit 1401 performs A / D conversion of the input reproduction signal to generate a disk ID signal 1402, and
The D signal is output to the encryption decoder 1413.

The encryption decoder 1413 decrypts the encrypted content data using the input disc ID signal 1402 as a key. At this time, if the content is recorded on the optical disk 1101 properly,
The key to decrypt the encrypted content recorded on the optical disk 1101 is the disk ID signal 1402 of the optical disk 1101, and the BCA playback circuit 14
The disc ID signal 1402 output from 01 is also the disc ID signal (BCAS) of the optical disc 1101. Therefore, the decrypted or descrambled content is output from the encryption decoder 1413 as the output signal 1414. Here, if the operation of the decoding process is #, it is expressed as the following equation.

[0088]

## EQU2 ## C [BCAS] # BCAS = C

Here, when the content data is image data, for example, the MPEG signal data is expanded,
The image signal data is obtained.

As described above, the encryption in this embodiment uses the disk ID as a key,
Since there is only one piece corresponding to one optical disc, there is an effect that the same encrypted content can be recorded only on the one optical disc. That is, when the content 1407 is copied from a regular optical disc having a disc ID of ID1 to another optical disc having another disc ID of ID2 and is to be reproduced, for example, the disc ID signal 1402 is output from the BCA reproduction circuit 401 as a disc ID signal 1402. ID2 is output. However, the encrypted content is a disk I called ID1.
Since it is encrypted with the D signal, the encryption decoder 1413
Therefore, the encrypted content cannot be decrypted.

Note that the encryption encoder 1408 is not a content supply source but is located on the recording / reproducing apparatus side with respect to the network, and may be in the form of an IC card or the like equipped with the encryption encoder. In addition, the optical disk 11
01 is encrypted only with the disk ID, so BC
It can be reproduced by any optical disk recording / reproducing device having the A reproducing circuit 1401 and the encryption decoder 1413.

<Fourth Embodiment> Next, an encrypted content recording method according to a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 20 is a block diagram showing a configuration of an optical disc recording / reproducing system according to a fourth embodiment of the present invention, in which encrypted content is recorded on a recordable optical disc which is a rewritable or write-once optical disc having a BCA. The device configuration is shown. The fourth
In the description of the third embodiment, portions common to the third embodiment will be simplified.

In FIG. 20, the optical disc recording / reproducing system according to the fourth embodiment is a CATV company device 150.
1, a key issuing center device 1507, a CATV decoder 1506, an optical disk recording / reproducing device 1514, and a television device 1530. Here, the CATV company device 1501 is a content memory 1 for storing content data such as movie software.
502, the first encryption key memory 15 for storing the first encryption key
03, and a first encryption encoder 1504. Also, the key issuing center device 1507 is
, A time limit information memory 1510 for storing time limit information, and a recording permission code memory 1511 for storing a recording permission code. Further, the CATV decoder 1506 stores a system ID for storing the system ID of the CATV decoder 1506.
A memory 1508, a first encryption decoder 1513, and a second
It has an encryption encoder 1516 and a company identification signal memory 1523 in the IC card 1522. Moreover,
The optical disk recording / reproducing device 1514 includes a recording circuit 1518.
, A data reproducing unit 1519, and a BCA reproducing circuit 1521
, A second encryption decoder 1520, and an IC card 1524
And an internal company identification signal memory 1526.

First, the first encryption encoder 1504 of the CATV company apparatus 1501 converts the content data in the content memory 1502 such as movie software into the first data.
By encrypting using the encryption key 1503, the first encrypted content 1505 is generated, and the generated first encrypted content 1505 is transmitted via the network to the first encryption decoder 15 of the CATV decoder 1506 of each user.
13 is transmitted. Here, if the data in the content memory 1502 is C, the first encryption key 1503 is FK, and the first encrypted content 1505 is C [FK], the following expression is used.

[0095]

## EQU3 ## C * FK = C [FK]

The CATV decoder 1506 has the system I
System ID of the CATV decoder 1506 in the D memory 1508 and the viewing or RAM type optical disk 11
01 is input in advance using the keyboard (not shown) of the CATV decoder 1506, for example.
09 with the key issuing center device 1 via the network.
507. Here, the title code 1509 may be input by selecting according to the screen of the TV, may be input directly from the keyboard, or may be input from a remote controller or the like. Therefore, the title code 1509 may be obtained by the user independently, or may be CATV together with the first encrypted content 1505.
It may be sent to the decoder 1506, or may be sent in advance in a form such as a program guide at a different time from the first encrypted content 1505.

Control unit 15 of key issuing center apparatus 1507
07a is the system ID of the CATV decoder 1506
Based on the content title code 1509 and the time limit information in the time limit information memory 1510 and the recording permission code in the recording permission code memory 1511, the key (K) 1512 corresponding to these is referred to. The data is transmitted to the first encryption decoder 1513 of the CATV decoder 1506 together with the recording permission code and the time limit code via the network. In addition, the case where the same content is broadcast a plurality of times at different times can be distinguished by the time limit information. Here, the first decryption key is FK
And the system ID of the CATV decoder 1506 is DI
D, the time limit information is TIME, the recording permission code is COPY, and the title code 1509 of the content.
Is T, the key (K) satisfies the following relationship.

[0098]

## EQU4 ## FK = K * T * DID * TIME * COPY

The recording permission code in the recording permission code memory 1511 is, for example, a CATV company device 1501.
Determines whether the content to be broadcast is a new work or an old work, and decides whether to permit viewing only or both viewing and recording.

The first encryption decoder 1513 of the CATV decoder 1506 includes a first decryption key (FK) and a key (K) 15
12, the title code 1509 of the content,
The system ID, the recording permission code, and the time limit information satisfy the above relationship, and the clock circuit 1527
If the current time information output from satisfies the condition of the time limit information, the first encrypted content 1505 is decrypted. Here, when the encrypted content is an image signal, the descrambled image signal is output from the first encryption decoder 1513 to the television device 1530 and can be viewed. Here, the first encryption decoder 15
13 is represented by the following equation.

[0101]

## EQU5 ## C [FK] # (K * T * DID * TIME * C
OPY) = C [FK] # FK = C

When the recording permission code permits only viewing, recording cannot be performed on the optical disk 1101, but when both viewing and recording are permitted, recording can be performed. Therefore, this method will be described below.

BCA of optical disk recording / reproducing device 1514
The reproduction circuit 1521 is provided for the BCA 11 of the optical disc 1101.
04 is reproduced to obtain a disc ID signal 1515, and the disc ID signal is output to the CATV decoder 1506.
To the second encryption encoder 1516. CATV
The second encryption encoder 1516 of the decoder 1506
Using the disk ID signal 1515 as the second encryption key,
By encrypting the data of the content output from the first encryption decoder 1513, a second encrypted content 1517 is generated and transmitted to the recording circuit 1518 of the optical disk recording / reproducing device 1514. The encryption of the second encryption decoder 1516 is limited to the time during which the first encrypted content is decrypted and output from the first encryption decoder 1513. Here, assuming that the content which is the output signal of the first encryption decoder 1513 is C, the disc ID signal 1515 which is the second encryption key is BCAS, and the second encrypted content 1517 is C [BCAS], Is written in

[0104]

[Mathematical formula-see original document] C * BCAS = C [BCAS]

The second encrypted content 1517 sent to the recording circuit 1518 of the optical disk recording / reproducing device 1514
Is modulated by a recording circuit 1518 according to, for example, a known 8/16 modulation method, and is recorded in a user data area 1 of an optical disk 1101 by an optical pickup (not shown).
103 is recorded. When playing back the content encrypted and recorded on the optical disk 1101, the laser beam output from the optical pickup irradiates the area of the optical disk 1101 where the encrypted content is recorded, and the reflected light is emitted. Light enters the optical pickup. The optical pickup photoelectrically converts the incident reflected light and outputs a photoelectrically converted reproduction signal to a data reproduction unit 1519. The data reproduction unit 1519 A / D converts the input reproduction signal into a digital reproduction signal. Output to the second encryption decoder 1520.

On the other hand, the laser beam output from the optical pickup irradiates the BCA 1104 of the optical disk 1101,
The reflected light enters the optical pickup. The optical pickup photoelectrically converts incident reflected light and outputs a reproduced signal obtained by the photoelectric conversion to the BCA reproducing circuit 1521. BCA
The reproduction circuit 1521 generates a disk ID signal 1515 based on the input reproduction signal and
20. In response, the second encryption decoder 1
520 decrypts the reproduced encrypted content output from the data reproducing unit 1519 using the input disk ID signal 1515 as a key. At this time, when the content is properly recorded on the optical disk 1101, the key for decrypting the encrypted content recorded on the optical disk 1101 is the disk ID of the optical disk 1101, and is output from the BCA playback circuit 1521. Since the disk ID signal is also the disk ID signal (BCAS) of the optical disk 1101, the second encryption decoder 1
520 can execute the decoding process normally. Therefore, the decrypted or descrambled content data is output as the output signal 1525 from the second encryption decoder 1520. Here, the decryption processing of the second encryption decoder 1520 can be expressed by the following equation. When the content is an image signal, the second encryption decoder 1520 expands, for example, an MPEG signal to reproduce the original image signal. And output.

[0107]

## EQU7 ## C [BCAS] # BCAS = C

Since the optical disk 1101 is encrypted only with the disk ID signal (BCAS) 1515, the BCA reproducing circuit 1521 and the second encryption decoder 1515 are used.
20 can be reproduced by any optical disk recording / reproducing apparatus having the same. Note that the encryption encoders 1504, 1
It has been described that the encryption is performed at 516 and the decryption is performed at the encryption decoders 1513 and 1520.
6, 1514, a program executed by the CPU, which is a control unit, may be provided with a program for an encryption algorithm and a decryption algorithm to execute encryption and decryption.

In the present embodiment, the second encryption encoder 1516 of the CATV decoder 1506 encrypts the content using the disk ID signal 1515 as the second encryption key, but the content may be encrypted as follows. Good. For example, an IC card 1522 prepared for each CATV company device 1501 is stored in a CATV decoder 1506.
, The company identification signal recorded in the company identification signal memory 1523 of the IC card 1522, and the disc ID signal (B
CAS) in combination with the second encryption key,
The content may be encrypted by the encryption encoder 1516. Here, the content which is the output signal of the first encryption decoder 1513 is C, the disk ID signal 1515 which is the first second encryption key is BCAS, and the second second
When the company identification signal 1523, which is the encryption key, is CK and the second encrypted content 1517 is C [BCAS, CK], the encryption processing of the second encryption encoder 1516 is expressed as the following equation.

[0110]

C * BCAS * CK = C [BCAS, CK]

Next, when reproducing the content recorded on the optical disk 1101 by encryption, the laser beam output from the optical pickup irradiates the area of the optical disk 1101 where the encrypted content is recorded. ,
The reflected light enters the optical pickup. The optical pickup photoelectrically converts the incident reflected light into a reproduced signal and outputs the signal to the data reproducing unit 1519. The data reproducing unit 1519 A / D converts the input reproduced signal into a digital reproduced signal and outputs the digital reproduced signal to the second encryption decoder 1520. On the other hand, the laser light output from the optical pickup is
And the reflected light is incident on the optical pickup. The optical pickup photoelectrically converts the incident reflected light into a reproduction signal and outputs the signal to the BCA reproduction circuit 1521. The BCA reproduction circuit 1521 reproduces the disk ID signal 1515 based on the input reproduction signal, and outputs the disk ID signal 1515 to the second encryption encoder 1516 and the second encryption decoder 1520.

Further, the optical disk recording / reproducing device 1514
The company identification signal in the company identification signal memory 1526 of the IC card 1524 attached to the
Input to 0. Note that the company identification signal does not have to be recorded in the company identification signal memory 1526 of the IC card 1524.
At the time of installation of the recording program of 514, the company identification signal may be recorded in a memory (not shown) connected to a CPU which is a control unit of the optical disc recording and reproducing device 1514. Instead, the company identification signal is sent to the keyboard (not shown) of the optical disk recording / reproducing device 1514.
May be input by using.

The second encryption decoder 1520 decrypts the encrypted content using the input disk ID signal 1515 and the company identification signal as a decryption key. At this time, the user of the CATV decoder
A formal contract is made with a specific CATV company having a company device 1502, and the content 1502
01, the first decryption key of the encrypted content encrypted and recorded on the optical disk 1101 is the disk ID signal (BCAS) of the optical disk 1101 to be reproduced, and the second decryption key is the second decryption key. Is the IC card 1 provided by the contracted CATV company
524 is a company identification signal (CK) in the company identification signal memory 1526. Therefore, the output signal 1525 of the decrypted or descrambled content is output from the second encryption decoder 1520. Here, the second encryption decoder 1
The decoding process at 520 is expressed as the following expression. When the content is an image signal, for example, an MPEG signal is expanded by the second encryption decoder 1520, and an output signal 1525 of the image signal is output.

[0114]

[Equation 9] C [BCAS, CK] # (BCAS * CK) = C

Since the contents of the optical disk 1101 are encrypted by the disk ID signal 1515 and the company identification signal, the CATV of the content provider is provided.
If you have a contract with the company, BCA playback circuit 1521
And can be reproduced by any optical disk recording / reproducing device having the second encryption decoder 1520. Conversely, if the user has not made a contract with the CATV company, the company identification signal cannot be obtained, so that the content cannot be reproduced, and the user can be differentiated from the contracted user.

In the present embodiment, each user sets the optical disc recording / reproducing apparatus 1 in the CATV decoder 1506 at home.
Since the disk ID signal is transmitted from 514 and the image data and the like are encrypted, the CATV company device 1501 does not need to individually change the encrypted content to be delivered to each user.
The broadcasting system can be simplified, the same contents can be provided to a large number of viewers at low cost. Further, according to the present embodiment, it is possible to permit recording on only one RAM type optical disk for each user having the CATV decoder 1506.

Although the present embodiment has been described with reference to the case where content is broadcast from the head end of cable television, the same applies to broadcasting by radio waves.

<Fifth Embodiment> A method for recording and reproducing encrypted content according to a fifth embodiment of the present invention will be described with reference to the drawings. FIG. 21 is a plan view showing a data recording area of an optical disc 1601 according to the fifth embodiment of the present invention, and FIG. 22 is a block diagram showing a configuration of an optical disc recording / reproducing system according to the fifth embodiment. is there. Note that in the fifth embodiment,
The description of the parts common to the third and fourth embodiments will be simplified.

In FIG. 21, reference numeral 1601 denotes a recordable optical disk which is a rewritable or write-once optical disk;
Is a control user data area in which disk information is recorded in the form of concave and convex pits, 1603 is a user data area for a user to record data by irradiating an optical disk with a laser beam, and 1604 is a disk ID. BCA.

In the BCA 1604, the recording film on the concave / convex pits in the inner peripheral portion of the control user data area 1602 is partially trimmed by a pulse laser such as a YAG laser to form a plurality of trimmings having a long shape in the radial direction. A region 1606 is formed. The trimming is performed by a disk manufacturer. Also, BCA
By adding a disk ID to the data recorded in 1604, management of the optical disk can be easily realized. Further, by recording the data of the BCA 1604 on the concave and convex pits, it is possible to prevent the information for identifying the optical disc recorded in the BCA 1604 from being easily falsified.

Further, the control user data area 1
Since the BCA 1604 and the BCA 1604 are adjacent to each other, the data of the BCA 1604 can be continuously reproduced when the data of the control user data area 1602 is reproduced, or the control user data area can be reproduced when the data of the BCA 1604 is reproduced. Since the data 1602 can be reproduced continuously, for example, when the optical disk is started, the CPU quickly obtains the information of the BCA 1604 for identifying the disk and speeds up the processing for recording the encrypted content. It becomes possible.

The BCA 1604 of this embodiment is formed by trimming the recording film on the concave and convex pits on the inner peripheral portion of the control user data area 1602. Are easily affected by heat with respect to the reflection film of the read-only optical disk. By trimming the inner peripheral portion of the control user data area 602, it is possible to protect the recording data of the user data area 1603 from heat generated at the time of trimming as compared with the case of trimming the outer peripheral part. The reason why the BCA 1604 is formed on the inner peripheral side of the control user data area 1602 is to consider a margin in the case where the spot diameter of the laser beam changes due to instability of the focus servo circuit. Note that data recorded in the BCA 1604 before trimming may be recorded in the control user data area 1602. Since the data recorded in the BCA 1604 is also recorded in the control user data area 1602, the data in the control user data area 1602 can be protected even if trimming is performed.

Further, when the data is continuously and repeatedly recorded from the BCA 1604 to the control user data area 1602, the position of the BCA 1604 is predicted by finding the data in the control user data area 1602. Can be.
Data in the key information recording area 1605 is recorded by irradiating a light beam in the same manner as in the user data area 1603.

As in the present embodiment, since the control user data area 1602 and the key information recording area 1605 are adjacent to each other, the control user data area 16
02 when reproducing the key information recording area 1605
Can be reproduced continuously, or when the data in the key information recording area 1605 can be reproduced, the data in the control user data area 1602 can be reproduced continuously.
BCA160 for PU to quickly identify disk
4 can be obtained and the process for reproducing the encrypted content can be accelerated.

In FIG. 22, the optical disk recording / reproducing system according to the fifth embodiment is a CATV company device 170.
1, a key issuing center device 1707, a CATV decoder 1706, an optical disk recording / reproducing device 1714, and a television device 1730. Here, the CATV company apparatus 1701 has a content memory 1702 for storing contents such as movie software.
And a first encryption key memory 1703 for storing the first encryption key
And a first encryption encoder 1704. Also,
The CATV decoder 1706 is a system ID memory 170
8, a first encryption decoder 1713, and a clock circuit 1725 that outputs current time information. Further, the key issuing center device 1707 includes a control unit 1707a that controls the operation of the device 1707, and a time limit information memory 1710 that stores time limit information. Moreover,
The optical disk recording / reproducing device 1714 includes a recording circuit 1717
, A key information recording circuit 1719, and a BCA reproducing circuit 172.
0, the data reproducing unit 1721, and the second encryption decoder 17
22 and a key information reproducing unit 1723.

First, the first encryption encoder 1704 of the CATV company apparatus 1701
Data of contents such as movie software in the
By encrypting using the encryption key 1703, the first encrypted content 1705 is generated and transmitted to the first encryption decoder 1713 of the CATV decoder 1706 of each user via the network. Here, the content memory 1
C in the first encryption key memory 17
Assuming that the first encryption key in 03 is FK and the first encrypted content 1705 is C [FK], the following expression is used.

[0127]

## EQU10 ## C * FK = C [FK]

The CATV decoder 1706 transmits, via a network, the system ID in the system ID memory 1708 of the CATV decoder 1706 and the title code 1709 of the content desired to be viewed and inputted, for example, using a keyboard (not shown). This is transmitted to the control unit 1707a of the key issuing center device 1707. The title code may be input by selecting it according to the screen of the television device 1730, may be input directly from the keyboard, or may be input from a remote controller or the like. Therefore, the title code may be obtained independently by the user, may be sent to the CATV decoder 1706 together with the first encrypted content, or may be different from the first encrypted content in a form such as a program guide. It may be sent in advance at the time.

Control unit 17 of key issuing center device 1707
07a is the system ID of the CATV decoder 1706
And a corresponding key (K) 1712 with reference to the corresponding time limit information in the time limit information memory 1710 based on the content and the title code of the content.
The data is transmitted to the first encryption decoder 1713 of the TV decoder 1706 via the network. In addition, the case where the same content is broadcast a plurality of times at different times can be distinguished by the time limit information. Here, the first decryption key is FK
And the system ID of the CATV decoder 1706 is DI
D, time limit information is TIME, and the title code of the content is T, the key (K) 1712 satisfies the following equation.

[0130]

## EQU11 ## FK = K * T * DID * TIME

The first encryption decoder 1713 includes a first decryption key (FK), the key (K) 1712 transmitted from the key issuing center device 1707, a title code of the content, a system ID, and time limit information. Satisfies the above relationship and the time limit information satisfies the condition of the current time information from the clock circuit 1725, the first encrypted content 1705 can be decrypted. Here, when the first encrypted content 1705 is an image signal, the descrambled image signal is output from the first encryption decoder 1713 to the television device 1730, and the user transmits the content to the television device 173.
You can watch at 0. Here, the first encryption decoder 1713
Is represented as in the following equation.

[0132]

## EQU12 ## C [FK] # (K * T * DID * TIME)
= C [FK] # FK = C

Next, the above-mentioned contents are transferred to the optical disk 160.
1 will be described. When recording content on the optical disc 1601, the CATV decoder 1706
The first encrypted content 170 not decrypted by
5 is transmitted from the first encryption encoder 1704 of the CATV company apparatus 1701 to the recording circuit 1717 of the optical disk recording / reproducing apparatus 1714. The recording circuit 1717 digitally modulates the received data of the first encrypted content 1705 using a modulation method such as a well-known 8/16 modulation method, and outputs the modulated digital data to an optical pickup (not shown). .) Is recorded on the optical disk 1601. Therefore, in order to play back the content encrypted and recorded on the optical disc 1601, it is necessary to decrypt the first encrypted content 1705.

The optical disk recording / reproducing device 1714 has a BC
The optical disc 16 reproduced by the A reproduction circuit 1720
The control unit 1707 of the key issuing center apparatus 1707 converts the disc ID signal 1715 of the key issuing center apparatus 1707 via the network with the title code 1716 of the content to be reproduced, which is input using, for example, a keyboard (not shown).
Send to a. The timing of sending the disc ID may be sent when accessing the key issuing center apparatus 1707, or may be sent together with the title code when viewing.

As a method of transmitting the disk ID, as shown in FIG.
Has been disclosed above, and the output signal of the BCA reproducing circuit 1720 is directly transmitted to the key issuing center apparatus 1707. However, the present invention is not limited to this, and the following method may be used. Before the access to the key issuing center device 1707, for example, when the disk is started, the data of the BCA 1604 is reproduced and stored in the memory (not shown) of the optical disk recording / reproducing device 1714 or the CATV decoder 1706, and the above timing is used. Key issuing center device 170
7 may be transmitted to the control unit 1707a. Furthermore, if the disc ID can be visually recognized in the form of a label or the like, the disc ID may be input from a keyboard, or if the label is a barcode, may be read from a barcode reader.

Control unit 17 of key issuing center device 1707
07a is the disk ID signal 17 of the optical disk 1601.
A key (DK) 1718 corresponding to 15 and the content title code 1716 is generated and transmitted to the key information recording circuit 1719 of the optical disk recording / reproducing device 1714. Here, when the first decryption key is FK, the disc ID signal 1715 of the optical disc 1601 is BCAS, and the title code 1716 of the content is T, the key (DK)
Satisfies the following relationship:

[0137]

## EQU13 ## FK = DK * BCA * T

The key (DK) input to the key information recording circuit 1719 of the optical disk recording / reproducing device 1714 is digitally modulated using a modulation method such as a well-known 8/16 modulation method. The information is recorded in the key information recording area 1605 of the optical disc 1601 by a pickup (not shown). It should be noted that a plurality of keys (DK) may be recorded in the key information recording area 1605. By recording a plurality of identical keys, the key (DK) can be protected when the recording film of the key information recording area 1605 is deteriorated or the optical disk 1601 is damaged. If the data of the key (DK) can be reproduced, the content can be decrypted.

Further, in the present embodiment, the key information recording area 1
605 is provided on the inner circumference side of the user data area 1603, but may be provided on the outer circumference side of the user data area 1603, or may be provided on both the inner circumference side and the outer circumference side. By being provided on the outer peripheral side, more keys (D
K) can be recorded. Further, by distributing a plurality of key information recording areas, even if one key information recording area cannot be reproduced, the key (DK) can be protected by another key information recording area.

On the other hand, the laser light output from the optical pickup irradiates the area of the optical disk 1601 where the content is recorded, and the reflected light is incident on the optical pickup. The optical pickup photoelectrically converts incident reflected light, and outputs a reproduced signal obtained by the photoelectric conversion to the data reproducing unit 1721. In response to this, the data reproducing unit 1721 A / D converts the input reproduced signal into encrypted digital data and outputs the digital data to the second encryption decoder 1722. Further, the laser light output from the optical pickup is
One BCA 604 is irradiated, and the reflected light is incident on the optical pickup. The optical pickup photoelectrically converts the reflected light incident thereon and converts the photoelectrically converted reproduction signal into a BCA reproduction circuit 17.
20. In response, the BCA playback circuit 17
20 reproduces the disk ID signal 1715 based on the input reproduction signal and outputs it to the encryption decoder 1722. Further, the laser light output from the optical pickup irradiates the key information recording area 1605 of the optical disk 1601, and the reflected light enters the optical pickup. The optical pickup photoelectrically converts the incident reflected light and outputs a reproduced signal to the key information reproducing unit 1723. In response to this, the key information reproducing unit 1723 transmits the key (D) based on the input reproduced signal.
K), and outputs the data to the second encryption decoder 1722.

When reproducing the content immediately after accessing the key issuing center apparatus 1707, the key information recording circuit 1719 stores the key (DK) in the key information recording area 1
Before recording to the second encryption decoder 172,
2 may be input. By doing so, it is possible to shorten the time until the reproduction is started. The encryption decoder 1722 outputs the input disk ID signal 171
5, a key (DK), and a decryption key composed of the title code 1716 of the content, to decrypt the encrypted content. The decryption processing of the second encryption decoder 1722 is represented by the following equation. When the content is an image signal, for example, an MPEG signal is expanded, and an output signal 1724 of the image signal is output from the second encryption decoder 1722.

[0142]

## EQU14 ## C [FK] # (DK * BCA * T) = C [F
K] # FK = C

In this embodiment, if it is assumed that a fee is charged when a key signal is received from the control unit 1707a of the key issuing center device 1707, it is assumed that the user is to be viewed and that the optical disk 1
When the content recorded on the optical disk 1601 is reproduced for the first time, the fee is charged separately. Therefore, in the case of charging for both viewing and recording on the optical disk 1601 at the same time, a user who wants to view but does not need to record on the optical disk 1601 or wants to record on the optical disk 1601, but does For a user who does not need to watch, the amount to be charged can be reduced. Also, the optical disk 1
The user is not charged for just recording on the optical disk 1601, so that the user can view the optical disk 1601 again after watching.
You can decide whether you want to receive a key to play the. In the above embodiment, the method of receiving the key (DK) from the control unit 1707a of the key issuing center apparatus 1707 via the network is used. However, the present invention is not limited to this, and the content title and the disc ID may be used.
By transmitting the number orally by telephone or the like, the number may be received orally and input from the keyboard.

Next, in the key information recording area 1605, the key (D
A case will be described in which the optical disk 1601 on which K) is recorded is reproduced after the access to the key issuing center device 1707 ends. First, a laser beam output from an optical pickup irradiates an area of the optical disk 1601 where the content is recorded, and the reflected light is input to a data reproducing unit 1721 via an optical pickup that performs photoelectric conversion. In response, the data reproducing unit 1721 outputs the encrypted content data to the second encryption decoder 1722. On the other hand, the laser light output from the optical pickup irradiates the BCA 1604 of the optical disk 1601 and the reflected light is input to the BCA reproducing circuit 1720 via the optical pickup that performs photoelectric conversion. In response, the BCA playback circuit 1720 generates a disc ID signal 1715 based on the input playback signal and outputs the disc ID signal 1715 to the second encryption decoder 172.
Output to 2.

Further, the laser beam output from the optical pickup is applied to the key information recording area 1605 of the optical disk 1601.
And the reflected light is input to the key information reproducing unit 1723 via an optical pickup that performs photoelectric conversion. In response to this, the key information reproducing unit 1723 generates key (DK) data based on the input reproduced signal and outputs the data to the second encryption decoder 1722. The second encryption decoder 1722,
Input disk ID signal 1715 and key (DK)
Then, the encrypted content output from the data reproducing unit 1721 is decrypted using the decryption key composed of the title code 1716 of the content. The decryption processing of the second encryption decoder 1722 is represented by the following equation. When the content is an image signal, for example, an MPEG signal is expanded, and the image signal is output from the second encryption decoder 1722.

[0146]

## EQU15 ## C [FK] # (DK * BCA * T) = C [F
K] # FK = C

Since the key (DK) data is recorded once in the key information recording area 1605, the encrypted content can be always reproduced without accessing the key issuing center device 1707. Also, since all the decryption keys necessary for the decryption processing are recorded on the optical disk 1601, the optical disk 1601 can be any optical disk having a BCA playback circuit 1720, a key information playback unit 1723, and a second encryption decoder 1722. It can be reproduced by a recording / reproducing device.

Further, when the encrypted content is copied to an optical disk 1601 having a different disk ID and is to be reproduced, a BCA reproducing circuit 1720 outputs a disk ID signal different from that of the optical disk 1601, so that the encryption is performed. The decrypted content cannot be decrypted, and the content is not reproduced even if copied. However, also in this case, the title of the content and the disc I
By transmitting D to the key issuing center via a network or verbally, a decryption key may be received after charging.
Thus, even if the encrypted content is copied to another optical disk 1601, it is not illegally reproduced, and the optical disk 1 on which the encrypted content is copied is not illegally reproduced.
Since the reproduction of the 601 is always accompanied by a charge, the copyright can be protected.

FIG. 23 is a table showing the structure of the ID assignment table according to the fifth embodiment. The key (K) input to the first encryption decoder 1713 when the system ID and the disk ID are different are different from the key (K). It shows the keys (DK) input to the information recording circuit 1719 in an organized manner. In FIG. 23, T1, T2 and T3 are title codes of different contents, and FK1, FK2 and FK3 are
It is a decryption key for decrypting encrypted content having title codes of 1, T2, and T3. Also, DID1,
DID2 and DID3 are system IDs of different CATV decoders 1706, respectively, and BCAS1, BCAS
2 and BCAS3 are the disk IDs of the different optical disks 1601 respectively. At this time, the CATV decoder 17
The key (Kmn) input to 06 is determined so as to satisfy the following equation.

[0150]

## EQU16 ## FKn = Kmn * Tn * DID * TIMEn

The key (DKmn) input to the optical disk recording / reproducing device 1714 is determined so as to satisfy the following equation.

[0152]

FKn = DKmn * BCAm * Tn

As shown in FIG. 23, not only when the contents are different but also when the contents are the same, the key information obtained from the key issuing center device 1707 is different for different CATV decoders 1706, different optical disks, and different broadcasting times. Therefore, it is possible to protect copyright in detail. Similarly, even if the content is the same, if the system ID, the disc ID, and the time information are different, the key information is different. Therefore, the CATV company apparatus 1701 does not need to change the encrypted content for each user, One encrypted content may be prepared.
This makes it possible to simplify the system at the time of broadcasting, and to provide contents to a large number of viewers at low cost.

Although the present embodiment has been described with reference to the case where content is broadcast from the head end of cable television, the same applies to broadcasting by radio waves.

<Effects of Third to Fifth Embodiments> The optical disc according to the present embodiment has a first information area in which first disc information is recorded and a second information area for identifying each disc. And a user data area in which information can be recorded by irradiating a light beam. Therefore, by adding information for identifying the optical disk to the conventional optical disk, the management of the optical disk can be easily realized. Here, the second information area is preferably
The information is recorded in the first information area, and can be reproduced by an optical pickup for reproducing the first information area. Further, the second information area is recorded by partially removing the recording film in the first information area so as to have a long shape in the radial direction and form a plurality of trimming areas. Therefore, it is possible to prevent the second disk information from being easily falsified.

Further, according to the method for recording encrypted content according to the present embodiment, the first information area in which the first disc information is recorded and the second disc information for identifying each disc. When recording content data in the user data area of an optical disc having a second information area in which information is recorded and a user data area in which information can be recorded by irradiating a light beam, at least the second information area is recorded. The content data is encrypted and recorded so that the content data can be decrypted and reproduced by the calculation using the disc information. Therefore, by encrypting the content by using the identification information of the optical disk that exists only in one specific optical disk, it is possible to prevent the illegal copying of the content and to protect the copyright. is there.

Further, the optical disc according to the present embodiment
In the user data area, there is provided a key information recording area for recording key information for decrypting the encrypted and recorded content. Therefore, in a system that requires key information when decrypting encrypted recorded content, the key information is recorded once in the key information recording area, so that it is not necessary to input the key information every time reproduction is performed. There is a unique effect.

Further, according to the method for recording encrypted content according to the present embodiment, the first information area in which the first disk information is recorded and the second disk for identifying each disk A second information area in which information is recorded, a user data area in which information can be recorded by irradiating a light beam, and content data encrypted and recorded in the user data area. When recording content in the user data area of an optical disc having a key information recording area for recording key information for decrypting the content data, the content data is decoded by at least the second disc information and an operation using the key information. The content data is encrypted and recorded so that it can be played back. Therefore, even if the encrypted content data is copied to another optical disk, it will not be illegally played back, and the playback of the optical disk on which the encrypted content data is copied must be charged. Copyright can be protected from.

Here, the first disk information is preferably composed of minute uneven pits, and the second disk information for identifying the optical disk is recorded on the uneven pits. Therefore, it is possible to prevent the second disk information from being easily falsified. More preferably, the first disk information and the second disk information are formed so as to be adjacent to each other. Thereby, when the first disk information is reproduced, the second disk information can be continuously reproduced, or when the second disk information is reproduced, the first disk information is continuously reproduced. For example, when starting the optical disc, C
It becomes possible for the PU to quickly obtain the second disc information for identifying the disc and to speed up the process for recording the encrypted content.

Further, according to the method of recording encrypted data according to the present embodiment, even if the contents are the same, the system ID,
If the disc ID and the time information are different, the key information is different. Therefore, the CATV company apparatus 701 does not need to change the encrypted content for each user, and only needs to prepare one encrypted content for one content. This makes it possible to simplify the system at the time of broadcasting, and to provide contents to a large number of viewers at low cost.

<Modifications of Third and Fifth Embodiments> In the third and fifth embodiments described above, FIGS.
As shown in the figure, the trimming areas 1105 and 1606 respectively include the control user data areas 1102 and 16
02 are formed on the BCAs 1104 and 1604 located on the inner peripheral portion in the second embodiment, however, the present invention is not limited to this.
And an optical disc 1101 according to a modification of the fifth embodiment
24 and FIG. 2 showing the data recording area of the data a and 1601a.
As shown in FIG. 5, the control user data area 110
2, 1602, the recording film is trimmed so as to protrude toward the inner peripheral side of the optical disc, and the trimming areas 1105a, 1105
606a may be formed. That is, BCA1104
a and 1604a are not included in the control user data areas 1102 and 1602, respectively, and are formed so as to protrude from the inner peripheral portions of the control user data areas 1102 and 1602 to the inside of the control user data areas 1102 and 1602. . In this modification, the reason why the BCAs 1104a and 1604a are formed in this manner is to consider a margin in a case where the spot diameter of the laser beam changes due to instability of the focus servo circuit. Also in this modification, since the user data areas 1103 and 1603 exist outside the controller user data areas 1102 and 1602, the data recorded in these user data areas 1103 and 1602 are protected so as not to be destroyed. To
The trimming regions 1105a and 1606a are arranged and formed.

<Sixth Embodiment> FIG. 26 shows the structure of a user data area in an optical disc according to a sixth embodiment of the present invention, and an optical disc reproducing apparatus for decoding encrypted content from data in the user data area. FIG. 3 is a block diagram showing the configuration of FIG. In the present embodiment, the optical disc is, for example, a recordable optical disc such as a DVD-RAM.

As shown in FIG. 26, the user data area 2
150 includes a sector header area 2101, a main data area 2102, and an error detection code 2103. The sector header area 2101 includes a sector address 2104 indicating the position of the sector, and a main data area 21.
02, copyright control information (including a scramble flag, copy control information, etc.) on data recorded in the main data area 2101 is recorded.
A decryption key area 2106 for decrypting when the data of 102 has been encrypted is included. The main data area 2102 is divided into an area in which the non-encrypted content 2107 is recorded and an area in which the encrypted content 2108 is recorded.
It includes control information of subsequent data such as a synchronization pattern in G and various control information. Further, the encrypted content 2108 mainly includes content data in which AV data or the like requiring copyright protection is encrypted.

In the decryption key area 2106, a decryption key for reproducing the succeeding main data area 2102 is recorded by being divided into a plurality of divided decryption keys having a predetermined size (hereinafter, referred to as divided decryption keys). Is done. For example, when the decryption key is 8 bytes for one 4-byte decryption key area, the 8-byte decryption key is divided into 4-byte divided decryption keys, and the decryption keys of two logically consecutive sectors are obtained. Area 21
06 and 2109 respectively record the two divided decryption keys. At the time of reproducing such a user data area, a plurality of divided decryption keys divided from decryption key areas 2106 and 2109 of a plurality of sectors which are logically continuous (however, unusable sectors due to defects or the like are skipped). Is obtained, the obtained necessary number of divided decryption keys are connected by the data connector 2111, and an encryption / decryption key (8
Bytes). For the data recorded in the main data area 2102 of the sector from which the encryption decryption key (8 bytes) could be obtained, the respective copyright control information 2105
According to the contents of the above, the decoding process is executed using the decoder 2114.

Further, in order to further increase the strength of encryption,
It is also possible to encrypt the decryption key, and to add the decryption key conversion data, which is information in the data, to the key so that the result of the encryption is not constant. It is also possible to provide different cryptographic results. Specifically, as shown in FIG. 26, the encryption / decryption key output from the data
2, the key decryptor 2112 decrypts the input encryption / decryption key into padding data (1 byte) as dummy data and a decryption key (7 bytes) using a predetermined disc key, and decrypts the key. Output to converter 2113. Here, the disk key is obtained by, for example, decrypting an encrypted disk key recorded on the optical disk by using a secret key which is a predetermined master key by a disk key decryptor (not shown). . Next, the key converter 2113
Using the decryption key output from the key decryptor 2112, the decryption key conversion data 2110 read from the main data area 2102 is subjected to data conversion by a predetermined conversion operation such as multiplication, division, or operation using a predetermined weighting coefficient. By performing the conversion, a content decryption key (7 bytes) is generated and output to the decryptor 2114. Then, the decoder 2114
By decrypting the content data read from the main data area 2102 using the content decryption key (7 bytes) output from the key converter 2113,
Generates and outputs the decrypted content data.
As the decryption key conversion data 2110, it is preferable to use data that can detect improper use of data immediately by falsification of copy generation management information or an analog macrovision control flag. .

FIG. 27 is a block diagram showing the arrangement of the copyright control information and the decryption key in the user data area and the arrangement of the encrypted content in the main data area in the optical disc according to the sixth embodiment. In an example of the user data area 2150 shown in FIG. 27, the decryption key area is a first decryption key area 2 having a 4-byte split decryption key.
201 and a second decryption key area 2202 having a 4-byte divided decryption key. Therefore, a plurality of sectors (two sectors in FIG. 27) are used regardless of the size of the encrypted content recorded in these two sectors. In this case, dummy data is recorded as complementary data in an unused area.
In the example of FIG. 27, the encrypted content 220 for one sector
If there are only four, the complementary data 2203 for one sector
Is recorded.

FIG. 28 is a block diagram showing an arrangement of the optical disk according to the sixth embodiment when an error correction unit extends over a plurality of sectors. For example, when the optical disc is a DVD, the error correction capability is enhanced by using a unit block (hereinafter, referred to as an ECC block) of an error correction code of 16 sectors. For this reason, when recording or reproducing data, recording must be performed in ECC block units. If the decryption key is divided into a plurality of arbitrary decryption keys and recorded, one decryption key may be recorded over a plurality of error correction blocks. At the time of reproduction, it is necessary to reproduce all of the plurality of divided decryption keys. Therefore, in addition to the sector in which the data of the encrypted content is recorded, the ECC block immediately before the recording of the decryption key is also reproduced. There is a need. The example of FIG. 28 is characterized in that the number of divisions for dividing the decryption key is set to a divisor of the number of sectors of the ECC block. As a result, the plurality of divided decryption keys are not recorded over the ECC block. Further, when only one type of decryption key is used as the decryption key used in one ECC block, and the AV data to be recorded is less than the ECC block, the complementary data
In addition, by arranging the complementary sector, it is possible to prevent data of an unnecessary sector from being read from the optical disc during reproduction.

<Seventh Embodiment> FIG. 29 shows a configuration of a lead-in area 2401 and a user data area 2402 in an optical disc according to a seventh embodiment of the present invention, and a structure of the lead-in area 2401 and the user data area 2402. FIG. 3 is a block diagram illustrating a configuration of an optical disc playback device that decrypts encrypted content from the data of FIG.

In FIG. 29, as in the sixth embodiment of FIG. 26, the lead-in area 2401 and the user data area 2402 each have a sector header area 2101, a main data area 2102, and an error detection code 2103. It is composed of sectors. Sector header area 21
01 is a sector address 2104 indicating the position of the sector.
And copyright control information 210 on which copyright control information (including a scramble flag, copy control information, etc.) relating to data recorded in the main data area 2102 is recorded.
5 is recorded, and the sector header area 2101 is recorded.
Is a recording position of the decryption key (referred to as a record in the decryption key table 2404 in the main data area 2102) for referring to a decryption key for decrypting the data in the main data area 2102 when the data is encrypted. A key index area 2403 for recording a key index indicating the position or storage position. The decryption key for decrypting the encrypted content recorded in the user data area 2402 is:
Lead-in area 2401 that can be rewritten in table format
In the form of a decryption key table 2404. The decryption key recorded in the lead-in area 2401 is referred to by the key index recorded in the key index area 2403. As in the sixth embodiment shown in FIG. 26, the above-mentioned decryption key is decrypted into padding data and a decryption key (or title key) by a key decryptor 2112 using a predetermined disk key. The decrypted decryption key (or title key) is converted to a content decryption key by a key converter 2113 that uses decryption key conversion data, and is output to the decryptor 2114. The decryptor 2114 generates and outputs decrypted content data by decrypting the encrypted content data using the content decryption key.

In the optical disk and the optical disk reproducing apparatus according to the seventh embodiment configured as described above, the key index area 24 in the sector header area 2101 is used.
03, by recording a key index for reference,
The decryption key size of the decryption key table 2404 can be assigned independently of the size of the key index area 2403. Further, even after the size of the decryption key table 2404 is allocated, a plurality of decryption keys are used successively from the decryption key table 2404 indicated by the key index in the key index area 2403, so that a decryption key having a free size can be obtained. Can be used.

FIG. 30A is a block diagram showing a data structure in the case where an unrecorded state is displayed by the initial value of the decryption key in the main data area 2102 of the lead-in area 2401 in the optical disc according to the seventh embodiment. It is. FIG.
In (a), unrecorded state data 2501 which is a known fixed value (for example, data such as all 0) which is not used as a key is recorded as an initial value of a decryption key recorded at the time of formatting an optical disc. By
This shows an unrecorded state of the decryption key.

FIG. 30B is a block diagram showing the data structure when the recording state is displayed in the decryption key state table in the main data area 2102 of the lead-in area 2401 in the optical disc according to the seventh embodiment. . FIG.
0 (b), the decryption key status table 2502 in a table format that can be referred to by an index is stored in the lead-in area 240 in the same manner as the decryption key shown in FIG.
1 and the recording state of the decryption key is stored in the recording state data 250.
3 is described as follows. (1) 0x00: unused, (2) 0x01: area reservation, (3) 0x03: key recorded, (4) other: reserved. Here, 0x indicates hexadecimal notation for the following character.

FIG. 31 is a block diagram showing the arrangement of decryption keys on the optical disc according to the seventh embodiment. FIG.
In the example 1, the arrangement of the decryption key area on the disk is devised in order to increase the reliability of the decryption key. Usually, defect management is performed in the user data area 2602,
When a write failure occurs, a replacement process is performed on an alternative area or the like. However, the lead-in area 2601
Then, the defect management as described above is not performed. For this reason,
Due to the occurrence of a writing defect or a reading defect, a decryption key required for reproducing AV data may become unusable, and furthermore, the optical disk itself may become unusable. Therefore, it is desirable to record a plurality of decryption keys in total over a plurality of different ECC blocks. Further, when a plurality of decryption keys are recorded in an adjacent area, all of the plurality of recorded keys may become unreadable due to scratches or dust. For this reason, as shown in FIG.
It is more preferable to record each decryption key at a position distant from the layout, such as the inner circumference side and the outer circumference side of the optical disk, in the readout area 2603 and the readout area 2603, respectively.

In the embodiment shown in FIG. 29, the decryption key areas are arranged in the lead-in areas 2401 and 2601. This is because the user data area 2602 is an area that can be accessed by a normal read command or write command, and is to increase the security when accessing from a drive device of a personal computer. Therefore, the same effect can be obtained even if these are arranged in the user data area 2602.

<Eighth Embodiment> FIG. 32 is a block diagram showing a data structure when data of an optical disc according to an eighth embodiment of the present invention is managed by a file management system. In the example of FIG. 32, the sector address where the desired file is stored is managed based on the structure of the file system.

In the file system structure defined by the International Organization for Standardization in ISO13346, the recording position of a file is managed using information called a file entry in order to support a rewritable optical disk. As shown in FIG. 32, for example, file (1) 2
The data at the recording position 703 is stored in the file management information area 2
751 is stored as a file entry (1) 2701, and data at the recording position of the file (2) 2704 is stored as a file entry (2) 2702. Each file is composed of extents 2705 and 2706 for managing areas of a plurality of continuous sectors on the optical disk. On the optical disc, the encrypted content described in the seventh embodiment is recorded in the main data area 2102 indicated by the file entry, and the decryption key is recorded in the decryption key table 2707 in the lead-in area 2601. User data area 2 in which encrypted content is recorded
In a sector header area 2101 in 602, a pointer indicating a recording position for referring to a decryption key required for decryption is stored.
Recorded in the key index area 2708. In the present embodiment, the decryption key is managed and recorded in file units and extent units. However, the present invention is not limited to this, and the decryption key is managed in at least one of the file unit and extent unit. May be recorded.

With reference to FIG. 33, a description will be given of a recording operation of a content requiring copyright protection on the optical disk managed by the file system as described above.
FIG. 33 shows a process of recording content requiring copyright protection, which is executed by the file management system according to the eighth embodiment.

At the time of recording the encrypted content, first,
In step S2801, the decryption key state table 2502 shown in FIG. 30B is read, and the free area of the decryption key table 2707 is checked. Next, in step S2802, it is determined whether or not there is an empty area in the decryption key table 2707. If NO, the decryption key for the encrypted content cannot be recorded, so the recording operation is stopped in step S2807 and the content Ends the recording process. On the other hand, in step S2802, Y
If it is ES, the obtained decryption key (or title key) is recorded. If the decryption key has not been obtained, the decryption key area is reserved. Next, step S28
In 04, the copyright control information of the content to be recorded (including information on whether to perform encryption and information on the type indicating the type of encryption, etc.) and the setting of the key index to be recorded in the key index area 2708 After performing step S2
At 805, the content is encrypted and recorded on the optical disk in a file format in extent units. At this time, the same copyright control information and key index may be used for each file, or they may be switched for each extent. That is, in steps S2804 and S2805, the unit to be processed is at least one of a file unit and an extent unit. Finally, in step S2806, the file management information for managing the recorded data is updated based on the information on the recorded content, and the recording process of the content ends.

FIG. 34 is a flowchart showing a content reproduction process executed by the file management system according to the eighth embodiment. FIG. 34 shows a process of reproducing content recorded in a file format from the optical disc by the method shown in FIG.

At the time of performing the file reproducing operation, the key index for the area indicated by the file entry in the file management information area 2751 is obtained in order to know the area of the decryption key table used by the file to be reproduced. Specifically, in step S2901, after the file entry of the file to be reproduced is read from the file management information 2751 and acquired by reproducing the file entry,
In step S2902, the value of the key index area is read from the sector header area 2102 of the area indicated by the file entry and is obtained by reproduction. If different encryption is performed for each extent, the key index area in the sector header is read for each extent. Next, step S2
In step 903, the decryption key is obtained by reading the decryption key from the decryption key area of the decryption key table 2707 indicated by the obtained key index and reproducing the decryption key. Further, in step S2904, the data of the content in the file is read out from the area indicated by the file entry and reproduced, and the data of the reproduced content is decoded. Here, if the playback and decryption of the content file are completed,
The content reproduction process ends.

FIG. 35 is a flowchart showing a content deletion process executed by the file management system according to the eighth embodiment. An operation of deleting data will be described.

When the file is deleted, the key index for the area indicated by the file entry is obtained in order to know the area of the decryption key table 2707 used by the file to be deleted. Specifically, in step S3001, the file management information area 2751
After the file entry of the file to be deleted is obtained from the file management information in the file, the value of the key index area is obtained from the sector header of the area indicated by the file entry in step S3002. Here, when different encryption is performed for each extent, the key index area in the sector header is read for each extent. Next, in step S3003, the decryption key is released from the decryption key area of the decryption key table 2707 indicated by the obtained key index (here, releasing the decryption key means deleting the decryption key from the table). After that, in step S3004, the file entry indicating the writing position of the file to be deleted is deleted from the file management information, and the process of deleting the content ends. In a traditional file system,
When deleting a file, only the file entry was deleted, but the decryption key recorded in another area cannot be deleted because the decryption key and the recording sector of the encrypted content are recorded in different areas. . In the above embodiment, the decryption key indicated by the key index in the sector header area is deleted from the decryption key table 2707 prior to the deletion of the file entry, thereby managing the decryption key on the optical disk.

<Ninth Embodiment> FIG. 36 is a block diagram showing the configuration of an optical disk system according to a ninth embodiment of the present invention. This optical disk system requires that the optical disk 3100 be protected from copyright. This is an information processing system for recording and reproducing contents to be reproduced. The optical disk system includes an encoding device 3101, an optical disk device 3102, a decoding device 3103, and a personal computer 3104.

An encoding device 3101 includes a content memory 3131 for storing content data, an encoding circuit 3132 for encoding the content data in the MPEG format, an encryption key memory 3133 for storing an encryption key, The encryption circuit 3134 encrypts the encrypted content data using the encryption key, generates a decryption key, and stores it in the decryption key memory 3111; a decryption key memory 3111 that stores the decryption key; A bus encryption circuit 3112 for encrypting content and an interface 3124 connected to the interface 3122 of the personal computer 3104 via the PCI bus 3151 to transmit encrypted content data and a decryption key. The optical disk device 3102 also includes a decryption key table memory 3113 that stores a plurality of decryption keys, a bus encryption and decryption circuit 3114, and a recording / reproducing device that records data on the optical disk 3100 and reads and reproduces data from the optical disk 3100. A circuit 3119;
Interface 3 of personal computer 3104
121 and an interface 3120 connected via a SCSI bus 3152 to execute processing such as transmission and reception of data and signals, signal conversion, and protocol conversion. Note that the SCSI bus 3152 may be an ATAPI bus. Here, the bus encryption and the bus decryption mean the PCI bus 3151 and the SCSI bus 3152, respectively.
The encryption processing and the decryption processing are used to encrypt and transmit the encryption key and the decryption key.

Further, the personal computer 3104
Is a control unit 3130 for controlling the operation, a bus encryption / decryption key table memory 3115 for storing a plurality of bus encryption / decryption keys, and a plurality of decryption key statuses (decryption) corresponding to the plurality of bus encryption / decryption keys. It indicates the recording state of the key, and specifically indicates unused, reserved area, recorded key, reserved, etc.), a decryption key state table memory 3116 for storing data, an interface 3120 of the optical disk apparatus 3102, and a SCSI. An interface 312 that is connected via a bus 3152 and executes processing such as transmission and reception of data and signals, signal conversion, and protocol conversion.
1 and the interface 312 of the decoding device 3103
3 and the interface 31 of the encoding device 3101
24 and an interface 3122 connected via a PCI bus 3151 to execute processing such as transmission and reception of data and signals, signal conversion, and protocol conversion. Furthermore, the decoding device 3103 is connected to the interface 3122 of the personal computer 3104, and performs transmission and reception of data and signals, and performs processing such as signal conversion and protocol conversion.
123, a bus decryption circuit 3117 for performing bus decryption on the encrypted decryption key received by the interface 3123
And a decryption key memory 3118 for storing a decryption key, and decrypting the data of the encrypted content received by the interface 3123 using the decryption key of the decryption key memory 3118, and performing a decryption process of the MPEG format to obtain an image signal. And a decoding circuit 3141 for generating an audio signal and outputting it to the display device 3105.

In the encoding device 3101 of this optical disk system, the encoding circuit 3132 encodes content data such as AV data stored or input in the content memory 3131 in the MPEG format. And encrypting the encoded content data using an encryption key in the encryption key memory 3133 generated to avoid unauthorized use of the content on the personal computer 3104,
Interface 3 for encrypted content data
The data is transmitted to the optical disk device 3102 via the personal computer 3104 and the personal computer 3104. Here, the encrypted content data is transmitted from the interface 3124 of the encoding device 3101 to the PCI bus 3151 and the interface 31124 of the personal computer 3104.
22 and the interface 3121 and the interface 3120 of the optical disk device 3102 to the recording / reproducing circuit 3119. Then, the encrypted content data is recorded on the optical disc 3100 by the recording / reproducing circuit 3119 of the optical disc device 3102.
Also, the recording / reproducing circuit 3119 of the optical disk device 3102
Reproduces the data of the encrypted content recorded on the optical disc 3100, and transmits the reproduced data of the encrypted content to the interface 3120, the interface 3121 and the interface 3122 of the personal computer 3104, and the interface 3123 of the decoding device 3103. Via the decoding circuit 3141
Send to Decoding circuit 314 of decoding device 3103
Reference numeral 1 denotes a decryption unit for decrypting the encryption of the data of the encrypted content and a decryption process in the MPEG format, and the image signal and the audio signal of the decrypted content are respectively displayed on a display device 3105 and a speaker device (not shown).
Output to

The encryption circuit 313 of the encoding device 3101
4 encrypts the content data encoded in the MPEG format using the encryption key in the encryption key memory 3133, and simultaneously generates a decryption key necessary for reproduction and generates a decryption key memory. 3111. It is necessary to record the encoded content data and the decryption key on the optical disk 3100. However, when the decryption key is to be handled as plain text on the personal computer 3104, the decryption key is read from the optical disk 3100 to obtain the encryption key. There is a possibility that the decryption of the data of the coded content becomes easy. In order to avoid this, mutual authentication is performed between the encoding device 3101 and the optical disk device 3102, and bus encryption is performed using a mutually shared bus key.

That is, specifically, the decryption key memory 31
11 is encrypted by the bus encryption circuit 3112 of the encoding device 3101, and the encrypted decryption key is transmitted to the interface 3124 and the PCI bus 315.
1 and the interface 3122 are stored in the bus encryption / decryption key table memory 3115 of the personal computer 3104. On the other hand, the optical disk device 3102
In the bus encryption and decryption circuit 3114, after decryption of the encrypted decryption key reproduced from the optical disk 3100 by the recording and reproduction circuit 3119, the decrypted decryption key is stored in the decryption key table memory 3113. You.
Further, the bus encryption and decryption circuit 3114 transmits, for example, the updated bus encrypted decryption key from the bus encryption decryption key table memory 3115 to the interface 3121, S
The data is received via the CSI bus 3152 and the interface 3120, is bus-decoded, and is decoded in the decryption key table memory 31.
After that, the data is recorded on the optical disk 3100 via the recording / reproducing circuit 3119.

After the decryption key state table is reproduced from the optical disk 3100 by the recording / reproducing circuit 3119,
The data is transferred to and stored in the decryption key state table memory 3116 via the interface 3120, the SCSI bus 3152, and the interface 3121. Further, the decryption key state table updated by the personal computer 3104 is read from the decryption key state table memory 3116, and the interface 3121 and the SCSI bus 3
After being transferred to the recording / reproducing circuit 3119 via the interface 152 and the interface 3120, the recording / reproducing circuit 3119 records the received decryption key state table on the optical disc 3100. Therefore, on the personal computer 3104 located in the middle, only the encrypted decryption key is handled by using the bus encryption decryption key table 3115 for storing a plurality of bus encryption decryption keys and the decryption key state table memory 3116. Security will be further secured.

Optical disk device 3102 and decoding device 3
Similarly, by performing the bus encryption of the decryption key during the period 103, further security is ensured. That is, the bus decryption circuit 3117 of the decoding device 3103 decrypts the encrypted decryption key received from the personal computer 3104 via the interface 3123, and decrypts the decryption key memory 311.
8 is stored. The decryption circuit 3141 includes the decryption key memory 3
The content data encrypted using the decryption key in 118 is decrypted.

As described in the seventh embodiment, when a decryption key for decrypting encrypted content data is recorded in a table format on the optical disk 3100, the optical disk device 3102 After the decryption key table reproduced in step 3 is bus-encrypted by the bus encryption and decryption circuit 3114, the data of the bus-encryption decryption key table is transferred to the bus encryption decryption key table memory 3 of the personal computer 3104 via the interface 3120.
Transfer to 115 and store. When recording content data, the personal computer 3104 searches the decryption key state table recorded on the optical disk 3100 in plain text for an empty area of the decryption key table to check the data, and performs bus encryption transferred from the encoding device 3101. And assigns the decryption key to the free area. At this time,
If an encryption that can be completed in decryption key units (for example, a block cipher in decryption key length units) is used as the bus encryption, there is no need to decrypt and re-encrypt the decryption key at the time of assignment to the decryption key block.

The optical disk device 3100, the optical disk device 3102, and the personal computer 3104
Since the decryption key table and the decryption key state table transferred and stored between and are data of one block, they can be called block data.

In the case of reproducing the content, only the decryption key necessary for decrypting the content to be reproduced from the decryption key block reproduced from the optical disk device 3102 is retrieved from the bus encryption decryption key table memory 3115. It is extracted, transferred to the decryption key memory 3118 via the personal computer 3104 and the bus decryption circuit 3117 of the decoding device 3103, and stored. The decryption circuit 3141 receives, via the personal computer 3104 and the interface 3123, the encrypted AV data reproduced from the optical disk 3100 by the recording / reproduction circuit 3119 of the optical disk device 3102, and receives the encrypted data. The AV data is decoded into an image signal or an audio signal using the decoding key in the decoding key memory 3118 and output. In this case, as in the case of recording the above-described content, if a cipher that is completed in units of decoding keys (for example, a block cipher in units of decoding key length) is used as the bus cipher, the decoding key from the decoding key block is used. When extracting
There is no need to decrypt the decryption key and re-encrypt. Further, when increasing the size of the decryption key, the optical disk device 31
02 can be easily and safely expanded on the personal computer 3104, such as allocating a plurality of decryption keys, without changing the configuration of the decryption key area.

<Tenth Embodiment> FIG. 37 shows a configuration of a user data area in an optical disc according to a tenth embodiment of the present invention, and an optical disc recording apparatus for encrypting contents and recording the contents in the user data area. FIG. 2 is a block diagram illustrating a configuration and a configuration of an optical disc playback apparatus that decrypts encrypted content from data in a user data area. This first
Embodiment 0 is characterized by adding a configuration of an optical disk recording device to Embodiment 6, and this configuration will be described in detail.

In the optical disk recording apparatus, in order to increase the encryption strength so that the encryption result is not constant,
The input encryption key is subjected to a predetermined key conversion operation such as multiplication, division, or operation using a predetermined weighting coefficient by a key converter 2119 using decryption key conversion data that is information in the content. After obtaining the content decryption key, the content data is encrypted using the content decryption key.

That is, when recording the content, the content data and the encryption key for encrypting the content data are input to the optical disk recording device. Here, the content data is stored in the key converter 2119 and the encryptor 2.
The key is input to the key encryptor 2118 and the key converter 2119. The key converter 2119 converts the input encryption key into first and second decryption key conversion data 2115 and 2116, which are partial information in the content.
By performing a predetermined key conversion operation using, a content decryption key is generated and output to the encryptor 2120. Next, the encryptor 2120 encrypts the data of the input content using the content decryption key, and converts the encrypted content into the user data area 2150 of the optical disc.
Is recorded in the AV data recording sector 2152.

Here, as the decryption key conversion data used in the optical disk reproducing apparatus, the second decryption key conversion data 2116 which is information in AV data which differs substantially on a sector basis, and a sector in which control information is recorded are used. The first decryption key conversion data 2115, which is copy control information including copy generation management information and an analog macrovision control flag included in the first key, is used. By using the former second decryption key conversion data, a content decryption key for encrypting the content data is provided for each sector, in accordance with the content of the second decryption key conversion data.
Can be restored. Further, since the latter first decryption key conversion data is data that can easily detect unauthorized use of the data at the time of falsification, when the first decryption key conversion data is falsified, the content data is decrypted. There is an effect that it is possible to easily make it impossible. Specifically, an encryption key is converted into a decryption key by a predetermined conversion operation using data of a playback control recording sector in which playback control information used for playback control of AV data is recorded as first decryption key conversion data. This is used as a content decryption key in the encryptor 2120. Further, the first data, which is data of the reproduction control recording sector,
And the second decryption key conversion data including the second decryption key conversion data that is a part of the non-encrypted content of the sector where the encrypted content is recorded. By performing a predetermined conversion operation, another content decryption key may be calculated, and this other content decryption key may be used as a content decryption key in the encryptor 2120.

On the other hand, the key encryptor 2118 generates an encryption / decryption key by encrypting the input encryption key using the disk key input in the same manner as the optical disk reproducing apparatus. Since the decryption key areas 2106 and 2109 in the sector header area are smaller than the size of the encryption / decryption key, the data divider 2121 divides the encryption / decryption key into a plurality of division / decryption keys, The keys are recorded in different decryption key areas 2106 and 2109. In the example of FIG. 37, the encryption / decryption key is divided into two encryption division / decryption keys, and the decryption key area 210
6,2109. Here, the key encryptor 211
Since encryption is performed on the decryption key, which is the encryption key, according to 8, the strength of encryption for the encryption key can be increased.

At the time of content reproduction, the key converter 211
3 uses the information of the above-described first decryption key conversion data 2115 and second decryption key conversion data 2116 to generate a key decryptor 2.
By performing a predetermined key conversion operation on the decryption key from 112, a content decryption key is generated and output to the decryptor 2114. Next, the decryptor 2114 obtains the decrypted content by decrypting the data of the encrypted content using the content decryption key. Here, the key converter 2113 may perform a predetermined key conversion operation on the decryption key from the key decryptor 2112 using information of only the first decryption key conversion data 2115.

<Eleventh Embodiment> FIG. 38 shows the structure of a user data area in an optical disk according to an eleventh embodiment of the present invention, and an optical disk recording apparatus for encrypting contents and recording the contents in the user data area. FIG. 2 is a block diagram illustrating a configuration and a configuration of an optical disc playback apparatus that decrypts encrypted content from data in a user data area. This first
The first embodiment is characterized in that the configuration of the optical disk recording apparatus is added to the seventh embodiment, and this configuration will be described in detail.

Referring to FIG. 38, the optical disk recording apparatus comprises:
As in the tenth embodiment of FIG. 37, a key encryptor 2118 for encrypting an encryption key using a predetermined disk key, and first and second decryption key conversion data 2115, 1515 in the content.
Key converter 2119 that performs a predetermined key conversion operation on an encryption key using 2116 to calculate a content decryption key
And an encryptor 2120 for encrypting content using the content decryption key. Here, the decryption key output from the key encryptor 2118 is the lead-in area 2
It is recorded in a main data area 2102 in 401. On the other hand, the optical disk reproducing device is configured to include a key decryptor 2112, a key converter 2113, and a decryptor 2114, as in the seventh embodiment of FIG. Here, the decryption key recorded in the main data area 2102 in the lead-in area 2401 is read and input to the key decryptor 2112. The key decryptor 2112 decrypts the decryption key using a predetermined disk key. And outputs it to the key converter 2113. Also, the key converter 2113 generates the first and second decryption key conversion data 21.
Using the decryption keys 15 and 2116, a predetermined key conversion operation is performed on the decryption key from the key decryption unit 2112 to calculate a content decryption key and output it to the decryption unit 2114.

<Effects of Sixth to Ninth Embodiments> As described in detail above, the recordable optical disc according to the present embodiment is
The decryption key is divided into a predetermined size decryption key area arranged in the sector header area and recorded, or a variable length decryption key is recorded in the decryption key area indicated by the key index area arranged in the sector header area. This makes it possible to provide a recordable optical disk that can use a decryption key of any length without being restricted to a decryption key area of a size defined in advance in the sector header area. This makes it possible to use encryption using an arbitrary key length according to the copyright protection level for the content to be recorded.

<Preferred Modification> In the above embodiment, the disc identification information is preferably constituted by non-rewritable pre-pits, and the disc identification information preferably indicates a region where the disc is used. Has a region identifier. The disc identification information preferably has a data category identifier indicating the type of content that can be recorded and reproduced on the optical disc. Further, the disc identification information is preferably
The data is encrypted using the secret key and recorded in the disc identification information area at the time of manufacture. Further, the disc identification information preferably includes data indicating a type of data recordable in the data recording / reproducing area or a type of data reproducible from the data recording / reproducing area.

In the above embodiment, preferably, there is provided a descrambling area management table for managing the correspondence between the sector area in which the content data is recorded and the descrambling key. The key management information area preferably has a descramble key area for recording a descramble key encrypted using the disc identification information as a key, and key information having a descramble key status area indicating a recording state of the descramble key. Area, a content information area for recording key information used when reproducing the content recorded on the disc, and a key index area for recording a pointer for referring to a descrambling key required for reproducing the content. . Further, in the sector where the data of the content is recorded, it is preferable to record a pointer indicating an area where the descramble key is recorded together with the data of the content.

In the above embodiments, the disc identification information reproducing circuit of the optical disc recording / reproducing apparatus preferably includes a circuit for decrypting the disc identification information encrypted using the secret key. In the optical disk recording / reproducing apparatus, the data encrypted using the disk identification information as a key is preferably content data such as image data or music data. Further, the disc identification information is
Preferably, the type of data that can be recorded in the data recording / reproducing area is indicated, and the disc identification information reproducing circuit determines whether or not the data is recordable content based on the type of data. Further, the data decrypted using the disc identification information as a key is preferably content data such as image data or music data. Also, the disc identification information preferably indicates the type of data that can be reproduced from the data recording / reproduction area, and the reproduction circuit of the disc identification information determines whether or not the data is reproducible content based on the data type. I do.

In the above embodiment, the content recording circuit preferably uses the same content data as encrypted image data and music data and the descrambling key for decrypting the content data. In the sector. Also, the content playback circuit
Preferably, content data such as encrypted image data and music data and a descrambling key for decrypting the content data are decrypted from the same sector.

In the above embodiment, the key area allocating circuit or method preferably arranges the area reserved flag in the descrambling key status area indicating the recording state of the descrambling key, and uses the area reserved flag when reproducing the data of the content. Information about the key to be recorded is recorded, and a key index indicating the recording area of the descramble key assigned to the content data is recorded. Also, the descrambling key arrangement circuit or method preferably reproduces an index of the descrambling key area used in the content from the content information area, and displays the descrambling key indicated in the key index corresponding to the descrambling key to be recorded. A descrambling key is arranged in the area, and a recorded flag is arranged in a descrambling key status area indicated by a key index corresponding to the descrambling key to be recorded.

In the above embodiment, the optical disk reproducing apparatus preferably reproduces the disk identification information, checks whether or not the content can be reproduced, reproduces the key management information, and reproduces the image management data such as image data and music data. The sector in which the content data is recorded is reproduced, and a descramble key is obtained from the reproduced sector. Further, preferably, the data of the reproduced content is descrambled by a descrambling key and output.

[0209] In the above embodiment, the method of recording content data is preferably a method in which a first information area in which first disc information is recorded and a second disc for identifying each disc. When recording content in the user data area of an optical disc having a second information area where information is recorded and a user data area where information can be recorded by irradiating a light beam,
The data is encrypted and recorded so that it can be decrypted and reproduced by at least the operation using the second disk information. Here, preferably, in the user data area, there is provided a key information recording area for recording key information for decrypting the encrypted and recorded data.

[0210] In the above embodiment, the method of recording content data is preferably a method in which the first information area in which the first disc information is recorded and the second disc for identifying each disc. A second information area in which information is recorded, a user data area in which information can be recorded by irradiating a light beam, and a content encrypted and recorded in the user data area. When recording content in the user data area of an optical disc having a key information recording area for recording key information, the content is decoded and reproduced by at least the second disc information and an operation using the key information. Encrypt and record so that you can do it.

In the above embodiment, in a sector of an optical disc having a decryption key area for recording a plurality of divided decryption keys into a plurality of continuous sectors, preferably, the size of data including AV data is (main). Dummy data is recorded in a main data area smaller than (data size) × (number of divisions of decryption key). Further, in the ECC block, preferably, a sector having a decryption key area recording a divided decryption key divided into a plurality of continuous sectors is recorded (ECC block unit) / (number of divisions of the decryption key) times, Dummy data is recorded in a main data area in which the size of data including AV data is less than (main data size) × (ECC block unit).

In the above embodiment, the decryption key for decrypting the encryption applied to the data including the AV data is preferably divided into a plurality of divided decryption keys having a predetermined size, and The divided decryption key is recorded in a plurality of continuous decryption key areas of the decryption key table. The decryption key table is preferably recorded in a main data area in a rewritable lead-in area. Further, information indicating the recording state of the decryption key table is preferably recorded as a fixed value in each decryption key area of the decryption key table. Further, the decryption key table is recorded a plurality of times in the different ECC blocks arranged on the inner and outer circumferences of the optical disc.

In the above embodiment, the encoding device 3101 as the data encryption device and the optical disk device 3102 as the optical disk recording / reproducing device are preferably
A bus key is shared by a mutual authentication method. Further, the decoding device 3103 as a data decoding device and the optical disk device 3102 as an optical disk recording / reproducing device preferably share a bus key by a mutual authentication method.

In the above embodiment, a recordable optical disk capable of recording data, which is a rewritable or write-once optical disk including a RAM type, has been described. However, the present invention is not limited to this. The present invention can be applied to a read-only optical disc which can read and reproduce the read data but cannot newly record. In the case of a read-only optical disc, the data recording / reproducing area is replaced with a data reproducing area for reading and reproducing data, and content data and other various control information data are recorded in advance during manufacturing. Here, recordable optical discs are CD-R, CD-RW, MO, MD, DVD
-Including RAM and the like. The read-only optical disk is music C
D, CD-ROM, DVD-ROM, etc.

[0215]

As described above in detail, according to the optical disk of the present invention, the first area is formed in the circumferential direction in the form of a stripe, and has the area where the signal of the reflected light amount is intermittently obtained. And an optical disk comprising: a second area in which a user can record user data by irradiating a second area with a light beam, wherein the first area is different from the second area. They are formed apart from each other so as to have a predetermined radial interval. Therefore, since the first region is formed apart from the second region, when forming the first region such as BCA, the recording film of the recordable optical disk is protected from heat generated during the formation. And user data recorded on the optical disk can be easily and reliably protected.

[Brief description of the drawings]

FIG. 1 is a plan view showing a data recording area of a recordable optical disc 100 according to a first embodiment of the present invention.

FIG. 2A shows a BCA1 of the optical disc 100 of FIG.
6 is a block diagram and a longitudinal sectional view showing an apparatus configuration when forming the optical disc 06. FIG.
5A and 5B are a vertical sectional view of the optical disc 100 after A106 is formed and a graph showing the intensity of reflected light in the horizontal direction.

FIG. 3 is a diagram showing a recording format of a BCA 106 in FIG.

FIG. 4 is a diagram showing a sector structure of sector data 401 in a user data area 102 of FIG.

FIG. 5 is a diagram showing a configuration of a key management information area 107 of FIG.

FIG. 6A is a diagram illustrating a modification of the first embodiment.
It is a block diagram showing a recording method for recording data,
(B) is the sector data 4 of FIG. 1 according to the first embodiment.
01 is the key index to the descramble key and A
FIG. 3 is a block diagram illustrating a recording method for recording V data.

FIG. 7 is a block diagram illustrating a configuration of an optical disc recording / reproducing apparatus according to a second embodiment of the present invention.

8 is a control CPU of the optical disc recording / reproducing apparatus of FIG. 7;
7 is a flowchart showing a recording process of AV data executed by the 710.

9 is a control CPU of the optical disk recording / reproducing apparatus of FIG.
8 is a flowchart illustrating a key management information area allocation process executed by a key management information area;

10 is a control CP of the optical disc recording / reproducing apparatus of FIG. 7;
It is a flowchart which shows the recording process of the descrambling key performed by U710.

11 is a control CP of the optical disk recording / reproducing apparatus of FIG. 7;
It is a flowchart which shows the reproduction | regeneration process of AV data performed by U710.

12 is a control CP of the optical disc recording / reproducing apparatus of FIG. 7;
It is a flowchart which shows the acquisition process of the descrambling key performed by U710.

FIG. 13 is a block diagram showing a method for determining whether or not an encrypted descramble key is a legitimate descramble key according to a modification of the first embodiment.

FIG. 14 is a diagram illustrating a configuration of a descrambling area management table according to a modified example of the first embodiment.

FIG. 15A shows whether or not content can be copied or reproduced in the same area and in different areas when an area identifier is recorded at the time of recording content in the first embodiment. FIG. 4B is a diagram illustrating a case where, in the first embodiment, when an area identifier is recorded in advance at the time of shipment of an optical disc, contents can be copied and reproduced in the same area and in different areas. FIG.

FIG. 16 is a plan view showing a data recording area of an optical disc 1101 according to a third embodiment of the present invention.

FIG. 17 is a BCA reproduction circuit 14 according to a third embodiment.
01 reproduction signal 1201 and reproduction binarized signal 12
It is a waveform diagram which shows the signal waveform of 07.

FIG. 18 is a BCA reproduction circuit 14 according to a third embodiment.
FIG. 2 is a block diagram showing a configuration of the first embodiment.

FIG. 19 is a block diagram illustrating a configuration of an optical disc recording / reproducing system according to a third embodiment.

FIG. 20 is a block diagram illustrating a configuration of an optical disc recording / reproducing system according to a fourth embodiment of the present invention.

FIG. 21 is a plan view showing a data recording area of an optical disc 1601 according to a fifth embodiment of the present invention.

FIG. 22 is a block diagram illustrating a configuration of an optical disc recording / reproducing system according to a fifth embodiment.

FIG. 23 is a table showing a configuration of an ID assignment table according to the fifth embodiment.

FIG. 24 is a plan view showing a data recording area of an optical disc 1101a according to a modification of the third embodiment.

FIG. 25 is a plan view showing a data recording area of an optical disc 1601a according to a modification of the fifth embodiment.

FIG. 26 is a block diagram illustrating a configuration of a user data area in an optical disc according to a sixth embodiment of the present invention and a configuration of an optical disc playback apparatus that decrypts encrypted content from data in the user data area.

FIG. 27 is a block diagram showing an arrangement of copyright control information and a decryption key in a user data area and an arrangement of encrypted contents in a main data area in the optical disc according to the sixth embodiment.

FIG. 28 is a block diagram showing an arrangement in a case where an error correction unit extends over a plurality of sectors in the optical disc according to the sixth embodiment.

FIG. 29 shows a lead-in area 2401 and a user data area 2 in an optical disc according to a seventh embodiment of the present invention.
FIG. 3 is a block diagram illustrating a configuration of an optical disc playback apparatus that decrypts encrypted content from data in a lead-in area and a user data area.

FIG. 30A is a block diagram showing a data configuration in a case where an unrecorded state is displayed with an initial value of a decryption key in a main data area of a lead-in area in an optical disc according to a seventh embodiment; (B) is a block diagram showing a data configuration when a recording state is displayed in a decryption key state table in a main data area of a lead-in area in an optical disc according to a seventh embodiment.

FIG. 31 is a block diagram showing the arrangement of decryption keys on the optical disc according to the seventh embodiment.

FIG. 32 is a block diagram illustrating a data configuration when data of an optical disc according to an eighth embodiment of the present invention is managed by a file management system.

FIG. 33 is a flowchart showing a recording process of a content requiring copyright protection, which is executed by the file management system according to the eighth embodiment.

FIG. 34 is a flowchart illustrating content playback processing executed by the file management system according to the eighth embodiment.

FIG. 35 is a flowchart illustrating content deletion processing executed by the file management system according to the eighth embodiment.

FIG. 36 is a block diagram illustrating a configuration of an optical disc system according to a ninth embodiment of the present invention.

FIG. 37 shows a configuration of a user data area in an optical disk according to a tenth embodiment of the present invention, a configuration of an optical disk recording apparatus for encrypting content and recording the content in the user data area, and encryption from data in the user data area. It is a block diagram which shows the structure of the optical disk reproduction | regeneration apparatus which decodes encrypted content.

FIG. 38 shows a configuration of a user data area in an optical disk according to an eleventh embodiment of the present invention, a configuration of an optical disk recording apparatus for encrypting content and recording the content in the user data area, and encryption from data in the user data area. FIG. 2 is a block diagram illustrating a configuration of an optical disc playback device that decodes encrypted content.

FIG. 39 is a block diagram illustrating a configuration of a user data area of a conventional DVD-ROM and a configuration of an optical disc reproducing apparatus that decrypts encrypted content from data in the user data area.

[Explanation of symbols]

100: optical disk, 101: lead-in area, 102: user data area, 103: lead-out area, 104: read-only area, 105: recording / playback area, 106: burst cutting area (BCA), 107: key management information area, 201: substrate, 202: recording layer, 203: reflection layer, 204: adhesive layer, 205: reflection layer, 206: recording layer, 207: substrate, 211: high power laser light source, 212: focus lens, 301: synchronization code, 302: error detection code, 303: error correction code, 304: BCA data, 305: disk identification information, 401: sector data, 402: header, 403: main data, 404: error detection code, 405: data ID, 406 ... ID error detection code, 407: Scramble control Information, 408, 408a: Key information, 501: Key information area, 502: Content information area, 503: Key index list area, 504: Number of recorded keys, 505: Descramble key area, 506: Key status area, 507 ... Number of contents, 508: Content information, 509: Key index, 701: Recordable optical disk, 702: Optical head, 703: Recording / reproduction control circuit, 704: Modulation / demodulation circuit, 705: Error detection and correction circuit, 706: Buffer memory, 707 ... descrambling circuit, 708 ... MPEG decoding circuit, 709 ... output circuit, 710 ... control CPU, 711 ... communication circuit, 712 ... data receiving circuit, 801 ... encryption descrambling key, 802 ... descrambling key, 803 ... error detection Code, 110 1101a ... optical disc 1102 ... control user data area 1103 ... user data area 1104, 1104a ... BCA, 1105, 1105a ... trimming area, 1201 ... reproduction signal, 1202 to 1204 ... trimming portion, 1205, 1206 ... slice level, 1207: reproduction binary signal, 1301: optical pickup, 1302: preamplifier, 1303: low-pass filter (LPF), 1304: binarization circuit, 1305: demodulation circuit, 1306: disk ID signal, 1401: BCA reproduction circuit 1402 ... Disc ID signal, 1403, 1404 ... Interface, 1405 ... Network, 1406 ... Encryption unit, 1407 ... Content memory, 1408 ... Encryption encoder, 1409 ... Encryption content , 1410 optical disk recording / reproducing device, 1411 recording circuit, 1412 data reproducing unit, 1413 encryption decoder, 1414 output signal, 1501 CATV company device, 1502 content memory, 1503 first encryption key memory, 1504 ... first encryption encoder, 1505 ... first encrypted content, 1506 ... CATV decoder, 1507 ... key issuing center device, 1507a ... control unit, 1508 ... system ID memory, 1509 ... inputted title code, 1510 ... time limit information Memory, 1511: Recording permission code memory, 1512: Key (K), 1513: First encryption decoder, 1514: Optical disk recording / reproducing device, 1515: Disk ID signal, 1516: Second encryption encoder, 1517: Second encryption Content 1515 recording circuit 1519 data reproducing section 1520 second encryption decoder 1521 BCA reproducing circuit 1522 IC card 1523 company identification signal memory 1524 IC card 1525 output signal 1526 company Identification signal memory, 1527 clock circuit, 1530 television device, 1601, 1601a optical disk, 1602 control user data area, 1603 user data area, 1604, 1604a BCA, 1605 key information recording area, 1606, 1606a ... Trimming area 1701 CATV company device 1702 Content memory 1703 First encryption key 1704 First encryption encoder 1705 Key (K) 1706 CATV decoder 1707 Key issuer Controller 1707a controller 1708 system ID memory 1709 input title code 1710 time limit information memory 1712 key (K) 1713 first encryption decoder 1714 optical disk recording / reproducing device 1715: Disk ID, 1716: Input title code, 1717: Recording circuit, 1718: Key (DK), 1719: Key information recording circuit, 1720: BCA reproduction circuit, 1721: Data reproduction unit, 1722: Second encryption decoder, 1723: Key information reproducing unit, 1724: Output signal, 1725: Clock circuit, 1730: Television device, 2101: Sector header area, 2102: Main data area, 2103: Error detection code, 2104: Sector address, 2105: Copyright Control information, 2 06: decryption key area, 2107: non-encrypted content, 2108: encrypted content, 2109: decryption key area, 2110: decryption key conversion data, 2111: data coupler, 2112: key decryptor, 2113: key converter, 2114: decryption device, 2115: first decryption key conversion data, 2116: second decryption key conversion data, 2117: non-encryption control information, 2118: key encryption device, 2119: key conversion device, 2120: encryption device, 2121 Data divider, 2150 User data area, 2151 Control information recording sector, 2152 AV data recording sector, 2201 First decryption key area, 2202 Second decryption key area, 2203 Complementary data, 2204 ... Encrypted contents 2401 Lead-in area 2402 User data area 2403 Key Index area, 2404: decryption key table, 2451: control information recording sector, 2452: AV data recording sector, 2501: unrecorded state data, 2502: decryption key state table, 2503: recorded state data, 2601: lead-in area, 2602 ... user data area, 2603 ... lead-out area, 2701 ... file entry (1), 2702 ... file entry (2), 2703 ... file (1), 2704 ... file (2), 2705 ... extent of file (1) 1), 2706: Extent (1) of file (2), 2707: Decryption key table, 2708: Key index area, 2751: File management information area, 3101: Encoding device, 3102: Optical disk device, 3103: Decoding device, 31 4 personal computer, 3111 decryption key memory, 3112 bus encryption circuit, 3113 decryption key table memory, 3114 bus encryption and decryption circuit, 3115 bus encryption decryption key table memory, 3116 decryption key state table memory 3117 bus decoding circuit, 3118 decoding key memory, 3119 recording / reproducing circuit, 3120, 3121, 3123, 3124 interface, 3130 control unit, 3131 content memory, 3132 encoding circuit, 3133 encryption key memory 3134: encryption circuit, 3141: decryption circuit, 3151: PCI bus, 3152: SCSI bus.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yuji Takagi 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Ryuji Yuba 1006 Kadoma Kadoma, Kadoma City Osaka Pref. (72) Inventor Mitsuaki Oshima 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. Motoshi Ito 1006, Kazuma, Kazuma, Kazuma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. (72) Inventor Takashi Ishida 1006, Kazuma, Kazuma, Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. (100) Matsushita Electric Industrial Co., Ltd. (72) Inventor Kohei Nakada 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-10-233019 (JP, A) (58) .Cl. ⁷ , DB name) G11B ^7/ 00-7/013 G11B 7/24 G11B 7/26

Claims (10)

(57) [Claims] A user is provided by irradiating a first region having a region formed in a stripe shape in the circumferential direction and having a region where intermittently a signal with a reduced amount of reflected light is obtained, and a second region with a light beam. an optical disk comprising a second region capable of recording user data, the first region is formed apart so as to have a predetermined interval in the radial direction relative to said second region, said first Data recorded in the area of 1 in the form of uneven pits
Is recorded also between the second area and the first area . 2. The optical disk according to claim 1, further comprising a lead-in area formed inside the second area, wherein the lead-in area includes at least a part of the first area. 3. The optical disk according to claim 1, wherein the second area is a rewritable area. 4. The optical disk according to claim 1, wherein the second area is a recordable area. 5. The light emitting device is formed in a stripe shape in a circumferential direction, and
With the area where the signal with reduced light intensity is intermittently obtained
A first region and a second region, wherein the first region is located radially relative to the second region.
The first region is formed so as to have a fixed interval and is spaced apart from the first region.
The data recorded in the form of uneven pits in the second area
An optical disc recording apparatus for an optical disc recorded also between an area and the first area, wherein a user can irradiate the second area with a light beam.
Optical disc recording apparatus comprising the recording means for recording the data. 6. A light emitting device, which is formed in a stripe shape in a circumferential direction and has a reflection shape.
With the area where the signal with reduced light intensity is intermittently obtained
A first region and a second region, wherein the first region is located radially relative to the second region.
The first region is formed so as to have a fixed interval and is spaced apart from the first region.
The data recorded in the form of uneven pits in the second area
An optical disc recording method for an optical disc recorded between an area and the first area, the method comprising: irradiating the second area with a light beam.
An optical disk recording method, comprising a step of recording data . 7. A light emitting device which is formed in a stripe shape in a circumferential direction, and
With the area where the signal with reduced light intensity is intermittently obtained
By irradiating the first area and the light beam to the second area.
A second area in which the user can record user data.
For example, the first region is at the radial direction relative to the second region
The first region is formed so as to have a fixed interval and is spaced apart from the first region.
The data recorded in the form of uneven pits in the second area
A playback device for playing back an optical disc recorded between an area and the first area, comprising: first playback means for playing back the first area; and a second area and the first area. Between the uneven pit shape
A second reproducing means for reproducing data recorded by the formula, and a second reproducing means for reproducing user data recorded in the second area.
An optical disc reproducing apparatus comprising: the reproducing means according to ( 3 ). 8. The light emitting device is formed in a stripe shape in a circumferential direction, and
With the area where the signal with reduced light intensity is intermittently obtained
By irradiating the first area and the light beam to the second area.
A second area in which the user can record user data.
For example, the first region is at the radial direction relative to the second region
The first region is formed so as to have a fixed interval and is spaced apart from the first region.
The data recorded in the form of uneven pits in the second area
A reproducing method for an optical disc recorded also between an area and the first area, the method comprising: reproducing the first area; Pit shape
An optical disc reproducing method, comprising: reproducing data recorded in a formula; and reproducing user data recorded in the second area. 9. set forth in any one of claims 1-4
Optical disc characterized by recording information on an optical disc
Disk recording device. 10. The method according to claim 1, wherein
Light for reproducing information from a recorded optical disc
Disc playback device.