WO2010116508A1

WO2010116508A1 - Managed copy method for protected contents, device using the managed copy method, and information recording medium used for the managed copy method

Info

Publication number: WO2010116508A1
Application number: PCT/JP2009/057273
Authority: WO
Inventors: 拓加藤; 和人黒田; 直樹森下; 裕治佐藤; 伸一松川; 尚志山田
Original assignee: 株式会社東芝
Priority date: 2009-04-09
Filing date: 2009-04-09
Publication date: 2010-10-14

Abstract

A function of superposing or writing information which cannot be deleted later on or to a copy source disk is installed in a terminal or the like having a managed copy function installed tehrein. When a managed copy is created from a released copy source disk to which no unique ID is written, the “information which cannot be deleted later” indicating that the managed copy is finished is superposed or written on or to the copy source disk. This makes it possible to manage a copy created from the same released disk.

Description

Patent application title: Management copy method of protected content, apparatus using the management copy method, and information recording medium used in the management copy method

The present invention relates to content protection technology.

The DVD video standard that appeared in 1996 adopted content protection technology called content scrambling system (abbreviated as CSS), so that users can not copy the content (title) recorded on the DVD video disc. . As a technique for suppressing such illegal copying of content, there is an optical disk apparatus described in Japanese Patent Laid-Open No. 2004-185663. However, with the spread of networks in recent years and diversification of playback devices and recording media, there is a movement to permit copying from DVD video discs to other recording media or recording devices under the control of a management server connected by a network. . In the case of a DVD video disc, a management server certified by a group called DVD CCA, which manages CSS technology, authorizes copying, and the copy managed in this way is called management copy (abbreviated as MC). be called. In MC, it is premised that copying is performed from a disk in which "information necessary for performing MC" is written in advance. Also, in order to enable the management server to manage from which disk how many copies have been made, the disk has information for identifying a title (title ID) and different identifications of the same title one by one Information (for example, unique ID) needs to be written. Furthermore, in order to perform MC, a management copier (abbreviated as MCM) in which the MC execution function is implemented is required. The MCM authenticates with the management server, sends a title ID and a unique ID to the management server, and receives an MC license from the management server. Actual MC is realized by various methods. The processing procedure of such an MC is also standardized in an advanced access content system (abbreviated as AACS) adopted as a content protection technical standard in HD DVD and Blue-ray Disc (or BD). The specifications of AACS are available from the Internet (http://www.aacsla.com/specifications/AACS_Spec_Prerecorded_0.92.pdf).

As in the MC processing procedure defined by the AACS standard, when a unique ID for identifying copy source media one by one is recorded in advance at the time of disc manufacture, accurate management of the MC is realized. However, since the current DVD video disc released or distributed does not have a unique ID written thereon, the disc can not be distinguished for each disc, and accurate MC management can not be realized.

One of the problems of the present invention is to enable management copy even from media in which identification information required for management copy is not recorded.

In order to solve the above problems, in one embodiment of the present invention, a copy source medium originally created as a ROM (Read Only Media) on information that can not be deleted later on a terminal or device equipped with a management copy (MC) function. With the function to write or overlap. Then, from a copy source medium (such as a DVD video disc and a ROM disc) in which the necessary identification information (such as a unique ID) is not written to the MC, another recording medium (such as a recordable optical disc or a memory card) and / or a recording device When an MC is created on a hard disk or the like, information indicating that the MC has been completed is written (or superimposed) on the copy source medium. In this way, it is possible to manage copy source media that have been used by the MC (for example, to manage the number of MCs of the same title created from the same medium).

FIG. 1 is a view for explaining the configuration of a terminal device used in the management copy method according to the embodiment of the present invention. FIG. 2 is a view for explaining an example of a management copy processing procedure. FIG. 3 is a view for explaining an example of a management copy creation procedure. FIG. 4 is a view for explaining another example of the management copy processing procedure. FIG. 5 is a view for explaining another example of the management copy creation procedure. FIG. 6 is a view for explaining an example of a reproduction waveform of information superimposed on a copy source medium. FIG. 7 is a view for explaining an example of the relationship between the frequency shift amount of superposition information and the servo residual deviation. FIG. 8 is a view for explaining an example of the arrangement of an apparatus for reproducing recording information from a copy source medium and superimposing or writing superposition information thereon; FIG. 9 is a view for explaining an example of the internal configuration of an RF amplifier and a data reproduction circuit in the device of FIG. 8; FIG. 10 is a view for explaining an example of the internal configuration of the demodulator shown in FIG. 9 (in the case of synchronous detection). FIG. 11 is a view for explaining another example (in the case of differential detection) of the internal configuration of the demodulator shown in FIG. 9; FIG. 12 is a view showing an example of a reproduction waveform when superimposition information is superimposed later on information already recorded from the beginning of manufacture on the reproduction-only optical disc.

First Embodiment FIG. 1 is a diagram for explaining the configuration of media and a terminal device used in a management copy method according to one embodiment of the present invention. Here, a released (distributed) DVD video disc 10 in which a unique ID for identifying each medium is not written is used as a copy source medium of management copy (MC). In this disc 10, a burst cutting area (abbreviated as BCA), a lead-in area, a user area and a lead-out area (or a middle area if the disc has two layers on one side) are prepared from the periphery of the center hole toward the disc outer periphery. (In the case of a single-sided dual-layer disc in which the middle area is disposed on the outer periphery of the disc, the lead-out area is disposed below the lead-in area). Data is written to the lead-in area, the lead-out area (or middle area) and the user area in such a manner that information written on a manufacturing disc (stamper) serving as a master is copied. Since DVD-ROM discs are mass-produced in this way, the same DVD-ROM disc is produced from the same stamper, but in BCA, different information is used for each disc with a YAG laser or the like in the post-production process. It is possible to write. Furthermore, it is possible to superimpose different information (a unique ID or the like for identifying each medium) on an information recorded area (lead-in area etc.) other than the BCA. The specific method of this information superposition (information addition which does not destroy the existing recording information) will be described later.

In FIG. 1, the network terminal 100 installed in “KIOSK” is illustrated as a management copy machine (MCM1 to MCMn). One or more MCMs 100 installed in one or more KIOSKs are network-connected to the management copy server (MC server) 200 via the communication I / F 50. This MCM 100 is used when creating an MC from a released DVD video disc (copy source disc 10 with no unique ID written) to another recordable disc (copy destination disc 20).

The MCM 100 includes a copy source disk drive 30, a copy destination disk drive 40, a communication I / F 50, a title determination unit 1000, an MC permission determination unit 1002, an MC complete mark read / write unit 1004, an MC condition presentation unit 1008, and an MC execution determination unit. 1010, MC processing execution unit 1020, unique ID code writing module 1030, user input unit (touch panel etc.) 1040, card reader / writer 1050, display unit 1060, control computer (CPU / ROM / RAM) 1070 etc. There is. The title determination unit 1000 is provided with a title determination unit 1001 that specifies a title recorded on the MC original disc 10. The determination unit 1002 determines whether the MC of the determined title is permitted. The read / write unit 1004 writes an MC complete mark to the copy source disc 10 when (or after) an MC complete mark reader 1005 for checking whether the copy source disc 10 is MC complete or not. An MC complete mark writer 1006 is provided. The presentation unit 1008 causes the display unit 1060 to present the condition (MC condition) for performing MC to the user when MC is possible. In other words, information corresponding to the content of the MC complete mark read from the disk 10 is displayed on the display unit 1060. The determination unit 1010 determines whether or not to execute the MC in accordance with the user's answer to the presented MC condition (user input from the user input unit 1040 and the recording of the user card 300 read by the card reader / writer 1050). .

The determination unit 1020 is configured to decode the title key decryption unit 1022 that decrypts the encrypted title key on the MC original disk 10, the disk key decryption unit 1023 that decrypts the disk key of the MC destination disk 20, and the decrypted title key. Title key encryptor 1024 that re-encrypts using the recorded disc key, a playback module 1025 that plays back the content (including navigation data) encrypted from the MC source disk 10, and the MC-destination disk 20 for the played-back content Recording module 1026 for recording information. Determination unit 1020 has a function of re-enciphering the encrypted title key on MC source disk 10 according to MC destination disk 20 when executing MC, and a function of copying the encrypted content of MC source disk 10 Have. When the MC is executed, information (MC completed mark) indicating that the MC is executed is recorded on the disc 20 at the MC destination, or a unique ID code (for example, its ID) identifying the executed device (specific terminal MCM1) The terminal maker name, product name, and a code combining the product number and the like are recorded by the module 1030 as the above-mentioned unique ID on the disc 20 at the MC destination. The payment of the user accompanying MC is made by the user's personal card (such as a cash card, a credit card, a prepaid card, or a point card) 300. The information on the user personal card and the information on the unique ID recorded on the disc 20 are registered in the MC server 200 via the communication I / F 50. The control of the registration operation and the MC operation is executed by software stored in the ROM, with the RAM in the control computer 1070 as a work area.

In the DVD video standard, a title ID for specifying a title recorded on a DVD-ROM disc is not defined. However, not only the recorded content data differs for each title, but also the navigation data constituting the menu or the like basically differs for each title. Therefore, it is possible at present even to distinguish released DVD video titles. Here, although the method of using the hash value of navigation data to distinguish a title (this hash value is used as a title ID) is used, the method is not particularly limited as long as the title can be distinguished. In addition, although the MC processing procedure in the KIOSK terminal is described for convenience in this example, the same MC function can be applied to a recording device (personal computer PC, DVD recorder, Blue-ray Disc recorder, etc.) for general users connectable to a network. Can be realized. Furthermore, the MC destination is not limited to the recording type optical disc (DVD or Blue-ray Disc). As in the prior art, it is possible to use various recording media such as a hard disk drive in a PC or recorder or a flash memory with a built-in pullable blade as the MC destination medium.

FIG. 2 is a diagram for explaining an example of the MC processing procedure. This process can be executed by the apparatus shown in FIG. 1 (this process is merely an example). The MCM 100 of FIG. 1 reads navigation data from the MC source disk 10 as information necessary for recognizing a title, and calculates a hash value by a known method (ST 100). Subsequently, the title is specified using the calculated hash value and a database not shown (abbreviated as DB: this is a DB on the MC server 200 and a hash value for each predetermined title is registered), and specified It is checked whether the title that has been received is a title that is permitted by the MC (ST102). If the specified title is not registered in the DB, or if it is a title for which MC is not permitted even though it is registered (No in ST104), necessary processing (such as notifying the user that copying is not possible) is performed. Then, the MC processing is ended (ST112). If the MC is a permitted title (ST104 Yes), the MC complete mark of the disc 10 is checked to determine whether the MC has been created from the disc 10. This "MC completed mark" is written or superimposed on the BCA of the disc 10, the lead-in area, the lead-out area, or the middle area as the "superimposition information" when the MC is already created in a form that can not be deleted later. ing. Alternatively, in the case where the superimposition information is composed of a plurality of bits so that a plurality of copies can be managed, the "MC completed mark" is the BCA of the disk 10 or the like when the MC number is counted up to the upper limit of a plurality of bits. It is written or superimposed in a form that can not be deleted later in the lead-in area or the like.

If the MC complete mark has been written or superimposed (No in ST106), the necessary processing (informs the user that the copy target title has already been copied from the disc and can not be copied anymore) Etc.) and then the MC processing is ended (ST112). When the MC completed mark is not written or superimposed (ST106 Yes), MC creation conditions such as a usage fee (price) of MC are presented to the user on the display unit 1060 (ST108). If the user does not agree with the MC condition (No in ST110), the necessary processing (eg, notifying the user that the copy has been canceled) is performed, and then the MC processing is ended (ST112). If the user is satisfied with the condition (ST110 Yes), MC creation processing is executed (ST120). When the disc 20 at the MC destination is created by this processing, information corresponding to the MC completed mark is superimposed on the existing pit row such as the BCA or lead-in area of the MC original disc 10). The recorded information (encrypted disk key, encrypted title key, encrypted content, etc.) of the MC source disk 10 is copied to the created MC destination disk 20, and a unique ID unique to the MCM 100 that created the MC is It is recorded (ST122). After that, the unique ID unique to the terminal device, and the information of the user who performed the MC (personal information of the card used for payment of the usage fee, etc.) are registered in the DB of the MC server 200 connected to the terminal device via the network. (ST124). By referring to that DB, it can be understood that a particular user has MC once and for all a particular title of a particular disc. If this registration is performed twice, it can be understood from the record of the DB of the MC server 200 that the specific title of the specific disc has been MC twice. When performing MC frequency and user management with MC server etc., instead of realizing more complicated management, the management load such as having to maintain the server for a long period of time also increases, but for each MC original disk When MC processing is simplified, such as permitting MC only once, network connection to manage MC times, user information, etc. by not permitting MC processing from the MC source disk on which the MC completed mark is superimposed. The MC can be realized by a simple system configuration without preparing the MC server and the like.

FIG. 3 is a diagram for explaining an example of the MC creation procedure. This procedure corresponds to the MC creation process ST120 of FIG. First, the MC complete mark (superimposition information) is written or superimposed on the MC original disk 10 (ST 1200). Then, it is confirmed that the MC complete mark (superimposition information) has been correctly written (or superimposed) (ST 1202). Subsequently, the encrypted disk key (Enc (Km, Kd)) and the encrypted title key (Enc (Kd, Kt)) are read from the MC original disk 10, and the master key (Km) concealed by the MCM 100 is used. The decrypted title key (Kt) is obtained (ST1204). Furthermore, the encrypted disk key (Enc (Km, Kd *) different from the encrypted disk key recorded on the MC original disk 10) recorded in advance on the MC destination disk 20 is read out and the MCM conceals Decrypt using the master key (Km) to obtain a disc key (Kd *) of MC destination (ST1206). The title key (Kt) is encrypted with the obtained MC destination disk key (Kd *) (ST 1208), and the encrypted title key (Enc (Kd *, Kt)) encrypted for the MC destination disk is MC destination The disc 20 is written (ST1210). Then, the encrypted content (Enc (Kt, Content)) on the MC source disk 10 is copied to the MC destination disk 20 (ST 1212). The content is copied onto the MC destination disk 20 according to the above procedure.

In the drawings of the embodiment, the unique ID is described on the MC destination disk 20. This unique ID can be used as well as MC processing in the prior art. That is, when registering the MC destination disk 20 in the DB of the server 200, it is conceivable to newly perform MC to another disk after the MC is completed, with the MC destination disk 20 as the original disk. It is possible to use the unique ID of the copy destination disk 20 when performing such MC (which can be realized by the prior art). When the MC according to the present invention is performed with the copy destination disc 20 as the original copy source, the unique ID may not be recorded on the disc 20.

Further, in the above-described embodiment, in order to simplify the description, the case of copying the encrypted content of the MC source disk 10 to the MC destination disk 20 without re-encrypting is described as an example. However, if the device (MCM) that executes the MC supports the content protection method according to the recording medium or recording device at the MC destination, the content is protected (re-encrypted) by a method different from the MC source. ) And copy to the MC destination. For example, when the MC source content is encrypted by CSS and the MC destination corresponds to AACS or CPRM (Content Protection for Recordable Media), the content may be re-encrypted according to AACS or CPRM.

Second Embodiment Next, a second embodiment will be described. In the first embodiment, the writing of the MC complete mark and the MC creating process are realized as a continuous process. On the other hand, in the second embodiment, necessary coupon information is issued to the MC in accordance with the writing of the MC completed mark. The issued coupon includes a unique ID for identifying the coupon, title information of the MC original disc, and the like, so that the MC can be created later according to the contents of the coupon. As a result, the MCM 100 such as KIOSK performs only "write processing such as MC completed marks etc. that can not be performed by conventional recording devices", and copying processing of encrypted content that can be performed even by conventional recording devices is user-owned devices ( It can also be separately performed by a DVD recorder, a BD recorder, etc.).

FIG. 4 is a diagram for explaining another example of the MC processing procedure (use of the above coupon). This process can be executed by the apparatus shown in FIG. 1 (this process is merely an example). The processing of ST100 to ST104 in FIG. 4 may be the same as the processing of ST100 to ST104 in FIG. If the title to be copied from the disc 10 is a title of MC permission (ST104 Yes), the MC complete mark and coupon information (if any) of the disc 10 are confirmed. If there is no coupon information, and the MC complete mark is written or superimposed (No in ST106), the necessary processing (eg, notifying the user that no more copying can be made) is performed, and then the MC processing ends. To do (ST112a). If there is coupon information and the MC complete mark is written or superimposed (No in ST106), the necessary processing (a user is notified that a coupon should be made with another network connection recorder since there is a coupon) Etc.), and then the MC processing is ended (ST112a). If the MC completed mark is not written or superimposed (Yes in ST106), the coupon issue conditions of MC including the usage fee (price) are presented to the user on the display unit 1060 (ST108a). If the user is not satisfied with the coupon issue condition (ST110a No), the necessary process (eg, notifying the user that the coupon issue has been cancelled) is performed, and then the MC process is ended (ST112a). If the user is satisfied with the condition (ST110a Yes), MC completed mark creation and MC coupon issue processing are executed (ST120a). By this processing, even when the copy creation using the MC destination disk 20 is later, the MC completed mark and the coupon information are written in the BCA of the MC original disk 10 (or MC completed on the existing pit row such as the lead-in area) Information corresponding to the mark and / or coupon is superimposed). Thereafter, coupon information and user information (user's card information and the like) are registered in the MC server 200 (ST124a), and the MC processing is ended (ST112a). After the MC complete mark and the coupon information are written in the copy source disc 10 and the coupon information and the user information are registered in the server 200, the user uses a recorder (not shown) at home connected to the network to The copy disc 20 of the specific title recorded in can be created for the number of sheets permitted for the issued coupon (ST1130).

FIG. 5 is a diagram for explaining another example of the MC creation procedure. This procedure corresponds to the MC creation process ST130 of FIG. 4 and is processed by a control computer (not shown) built in the network connection recorder on the user side. First, it is confirmed that the MC complete mark and the coupon information (superimposition information) are correctly written or superimposed (ST1300). If the MC completed mark and the coupon information are correctly written or superimposed, the usage status of the corresponding coupon is acquired from the DB of the server 200 of FIG. 1 (ST1301). For example, when the acquired usage status indicates that “the corresponding coupon has been used” (No in ST1302), the process ends without creating a copy on the user side. On the other hand, for example, when the obtained usage status indicates that "the corresponding coupon is not used" or "the corresponding coupon is for n copies of the coupon and the coupon is not used up" (ST1302 Yes), The same processing (ST1304 to ST1312) as in ST1204 to ST1212 is performed. As a result, the coupon issue target title (protected content) is copied from the MC source disc 10 to the MC destination disc 20. When this copying is performed, unique ID information unique to the recorder used for the copying is created and recorded on the copy destination disc 20 (ST 1330). Then, when the copy creation to the copy destination disc 20 is completed, the management copy server 200 asks the management copy server 200 that “the corresponding coupon has been used” or “the corresponding coupon is n copies of the copy and the coupon is used once Or "the corresponding coupon is a copy n times, and the coupon can be copied m times later" (ST 1332).

Third Embodiment The third embodiment will be described below with reference to FIGS. 6 to 11. Here, for example, an apparatus which performs recording on a read-only disc (abbreviated as a ROM disc) by causing an irreversible change to a recording film of a data area (lead-in area etc.) on the DVD disc 10 of FIG. The method of writing the above-described superposition information by the optical disk drive) will be described in detail. The apparatus shown in FIG. 8 corresponds to FIG. 2 of JP-A-2009-54281 published on Mar. 12, 2009 (the disclosure of JP-A-2009-54281 is part of the disclosure of the present application). It is recommended to refer to this publication when you want to know the device of FIG. 8 in more detail.

<01> A laser is irradiated onto the pits of the ROM disk to record the mark space. Although the specific method will be described later, it is possible to perform superimposition information recording in a state where the data originally recorded on the ROM disk can be read by the irreversible change to the recording film, or to the ROM disk originally It is also possible to perform superimposition information recording to make it difficult to read the recorded data.

<02> When irradiating a laser onto pits of a ROM disk to record marks and spaces, constant envelope modulation (or constant amplitude modulation) is used so as not to affect the servo. In particular, frequency shift keying (abbreviated as FSK) is used for this modulation. Although superimposition information can be recorded on a ROM disk, a method of modulating a recording signal of superimposition information will be described below. Generally, DPD (phase difference detection method) is used as an error signal of track servo when reproducing a ROM disk. When the ROM disk on which the superimposition information is recorded is reproduced, as shown in FIG. 6, repetition of the amplitude center fluctuation generated in the signal received by the superimposition information recording occurs, which causes the track servo error signal to be generated. Disturbances such as offsets and amplitude fluctuations may occur. Although FIG. 6 shows that the data originally recorded on the ROM disk and the phase of the modulation cycle of the superposition information coincide with each other, in actuality, the synchronous / asynchronous state of the recording data and the superposition information It does not matter. Also, Tsb is the reciprocal of the recording bit rate in the recording bit cycle of the superposition information. If the frequency band of the energy of this disturbance is below the frequency of the track servo band (2.4 kHz in the case of 1 × DVD), the track servo responds to the disturbance and the recorded superimposition information is also There is a risk of deviation from the tolerance of track deviation which can be obtained well including the reproduction signal. On the other hand, if the modulation carrier frequency is increased to reduce the influence on the servo band, the signal competes with the frequency band of the data originally recorded on the ROM disk, and the influence of the recorded data causes a signal of superimposed information. The noise to noise ratio degrades rapidly. In consideration of these tradeoffs, the carrier frequency of the modulation and the modulation scheme are selected as follows.

<03> The modulation carrier frequency is below the RF band and above the servo band. The upper limit of the modulation carrier frequency (RF) is the lower cutoff frequency (-3 dB drop point) of the data originally recorded on the ROM disk in order to filter out the data originally recorded on the ROM disk . In the case of single-speed playback of a read-only DVD, this low frequency cutoff frequency is approximately 70 kHz. The lower limit of the modulation carrier frequency needs to be higher than the servo band as described above, excluding the limitation of the recording bit rate of superimposed information, and is 2.4 kHz in the case of 1 × speed of DVD. By selecting the modulation carrier frequency in this manner, superimposition information can be recorded / reproduced without being influenced by the data originally recorded in the ROM disk and without affecting the servo band, and signal-to-noise of the superimposition information The ratio improves. As a result, the reading error rate of superimposed information can be reduced. Incidentally, conventionally, in the case of an optical disc, reproduction may be performed at a reading speed equal to or higher than a standard reading speed (1 × speed), and in this case, low frequency cutoff of data originally recorded on the ROM disc in proportion to the double speed The frequency changes. Further, in the case of the recently appeared Blue-ray Disc, the low frequency cutoff frequency of data recorded on the ROM disc is about 200 kHz in single-speed reproduction. Although the servo band varies depending on the disc type and the reproduction double speed, it is rare to exceed 10 kHz because of the ease of mechanical realization.

<04> The FSK frequency shift amount is selected so as to reduce the influence on the servo. Assuming that 1-fold overlap information of 264 bits (header portion 8 bits + data portion 256 bits) is written on the inner peripheral portion of the disc by binary frequency FSK, the recording bit rate of the superposition information is about 7.8 kbps and the disc rotation period The modulation frequencies are as shown in Table 1.

According to the experiments of the inventors, the increase in the effective value (RMS value) of the residual deviation of the track servo error signal when the portion where the superposition information is recorded by the recording method is reproduced is compared to the state before recording. It shows a change as shown in FIG. From this, 31.3 kHz (the first frequency) and 39.1 kHz (the second frequency) in order to make the influence of the modulation 1% or less (0.00022 μm) with respect to the tolerance of the track servo error defined in the DVD standard. Recording is performed with a smaller amount of frequency shift than the combination of

The number of waves constituting one channel bit of <05> FSK / PSK is set to 7 waves / 8 waves to make it resistant to disturbance. The larger the number of waves constituting one recording bit cycle, the stronger the disturbance (noise). In the example of Table 1, the case of wave number 7 of data 0 / wave number 8 of data 1 is the strongest in disturbance.

The number of waves constituting one channel of <06> FSK increases the density as one wave / 1.5 waves. As described above, the frequency usable for modulation has an upper limit of 70 kHz, for example, in the case of DVD single speed. The maximum recording bit rate at which "the switching point of the first frequency and the second frequency becomes continuous combination" is 46.7 kHz as the first frequency (one wave) and 70 kHz as the second frequency (1.5 wave) The recording bit rate is 23.3 kbps, and 790 bits can be recorded for the innermost track. However, they are vulnerable to disturbances.

<07> FSK is a three-value FSK, and the third frequency is allocated only to the header portion and to frequencies other than data (0/1) to facilitate detection. In order to specify the top bit position of the superimposition information at the time of superimposition information reading, a bit string (header portion) indicating the top is necessary. As described above, since there are upper and lower limits on the recordable carrier frequency, it is desirable to reduce the number of bit strings for the header portion when trying to secure the data amount of the superimposed information within the limited area. In order to realize this, the third frequency is assigned to the header section as ternary FSK. As a result, it is only necessary to detect the presence of the third frequency for detecting the header portion, so that the length of the header portion can be made to be the length of one bit of the superposition information, and it is possible to efficiently Superimposition information can be recorded. An example in which the third frequency is combined in this way is shown in Table 2.

<08> Use MSK for modulation. Although the details of the method of reading the superimposed information described above will be described later, it is also preferable to use minimum frequency shift modulation (abbreviated as MSK) as a modulation method in order to simplify the reading means. MSK is a kind of FSK and satisfies the following equation (1). (N is an integer)
(First frequency-second frequency) ÷ recording bit rate of superimposed information = N ÷ 2 (1)
As described above, if the first frequency, the second frequency, and the recording bit rate are selected, it is possible to use the delay detection with a simple configuration as shown in FIG. 11, compared to the synchronous detection method as shown in FIG. Demodulation becomes easy. (When using FSK which does not satisfy Formula (1), the synchronous detection method as shown in FIG. 10 may be used.) When MSK is used, the restriction on the modulation frequency will increase if it is ternary. Therefore, for example, the header part doubles the recording bit rate by the header part. A demodulation block diagram in this case is shown in FIG. In this case, even if the recording bit rate is doubled, the MSK relationship needs to be satisfied, so the following equation needs to be satisfied. (N is an integer)
(First frequency-second frequency) ÷ recording bit rate of superimposed information = N (2)
As a result, for detection of the header portion, it is only necessary to detect a portion at which the recording bit rate is doubled, and the length of the header portion can also be set to a length corresponding to one bit of the superposition information. Then, superimposition information can be efficiently recorded in a limited area, and it is possible to use delay detection (FIG. 11) and demodulation becomes easy. Not only MSK but also demodulation using two waves in an orthogonal relationship can be similarly performed by differential detection. In the case of differential detection, the polarity of the demodulation output may be reversed. Therefore, the CPU 90 shown in FIG. 8 needs to determine the polarity from the demodulation result to obtain data of the correct polarity. Also in this case, the polarity can be easily determined by utilizing the fact that the header portion has a fixed pattern.

<09> Use PSK for modulation. In addition to FSK and MSK described above, phase modulation (abbreviated as PSK) can also be used as a method of modulating superimposed information.

<10> The modulation carrier frequency is selected as a frequency to be removed by the HPF of RF so that channel data can be read even after recording. As shown in FIG. 6, the recording of the superimposition information causes “a repetition of amplitude center fluctuation” in the signal received from the laser light reflected by the disc. Therefore, in the reproduction of the data originally recorded on the ROM disk, the “appropriate binarization level” fluctuation occurs repeatedly at the modulation frequency of the superimposed information. The carrier frequency of the modulation is a frequency sufficiently smaller than the low band removal filter (abbreviated as LEF) 302 of the signal processing circuit (FIG. 9) for reproducing the data originally recorded on the ROM disk, or a binarizer If the frequency is sufficiently lower than the cutoff frequency of the decision feedback circuit 305 (5 kHz at 1 × DVD speed), the influence of the “appropriate binarization level” fluctuation generated by the superposition information recording is suppressed, so the superposition information recording After that, it is possible to read the data originally recorded on the ROM disk. Thus, the superimposition information can be recorded without destroying the data recorded on the ROM disk. When such recording is performed, even if superimposing information is recorded not only in the lead-in area but also over the entire surface of the disc, the data originally recorded on the ROM disc can be reproduced. It is possible to increase.

<11> The modulation carrier frequency is selected to a frequency that is not removed by the HPF of RF so that channel data can not be read after recording. The carrier frequency of modulation is a frequency sufficiently smaller than LEF (or RF high pass filter HPF) 302 of the signal processing circuit that reproduces the data originally recorded in the ROM disk, or the cut of the decision feedback circuit 305 of the binarizer If the frequency is not sufficiently lower than the off frequency, the influence of the “appropriate binarization level” fluctuation generated by superposition information recording is not suppressed. In that case, even after superimposition information recording, reading of data originally recorded in the ROM disk becomes difficult. If it is detected that reading of data becomes difficult (for example, it is detected that error correction operation of read data frequently occurs in an ECC processing circuit not shown), whether or not the superimposing information is recorded without reading the superimposing information Since it can be determined, depending on the application, it may be preferable to make it difficult to read data of a portion where superimposition information is recorded after superimposition information recording.

<12> When the mark / space is recorded by irradiating the laser onto the pit of the ROM disk, the location is changed and additional writing is performed. At this time, laser power control is performed so as not to record on the adjacent track. It is suitable for the application which permits a plurality of copies, for example, adding the superimposition information one round at a lead-in area each time a copy is performed. In this case, recording is performed with a power (this power is determined experimentally) such that adjacent tracks are not affected by the recording of the superimposition information, and the superimposition information previously recorded and the superimposition information to be recorded next will be recorded. Do not affect the

The superposition information is written by a device (the device of FIG. 8 or the disk drive 30 of FIG. 1 or the like of FIG. 1 or the device of FIG. Can be controlled.

Fourth Embodiment The disk 10 shown in FIG. 1 has disks of various structures such as single-sided single layer, double-sided single layer, single-sided double-layer. In the future, it is possible that a single sided disc having three or more layers may be commercially available, but here, the cross-sectional structure of a large number of existing single sided dual layer discs is exemplified. The single-sided dual-layer disc 10 is formed of a transparent material for laser light and formed with a pit P on the substrate 0 and the pits of the substrate 0 sequentially from the side receiving the focused beam LB of the reading laser. And an intermediate layer 3 transparent to the laser light, and a reflective layer 4 formed on the pits P of the substrate 1 and totally reflecting the laser light. There is. The pit surface of the substrate 1 constitutes a first information recording layer (L0 layer), and the pit surface of the substrate 0 constitutes a second information recording layer (L1 layer). The pit surface of the substrate 1 and the pit surface of the substrate 0 are bonded by an intermediate layer 3 using an ultraviolet curable resin or the like. When this disk 10 is, for example, a single-sided three-layer disk, a third layer (L2) comprising a semitransparent reflective layer and a transparent substrate between the substrate 0 and the substrate 1 (positionally, between the intermediate layer 3 and the L0 layer) Layer) is provided. If a layer having the same configuration as the L2 layer is further added, an optical disc having a multilayer structure of four or more layers is obtained. In the case of a single-sided single layer disc, the semitransparent reflective layer 2 is not present, and only the total reflective layer 4 is provided.

The disk 10 of FIG. 1 can be manufactured, for example, by the following process. First, an L0 molded substrate on which a pit for L0 is transferred from a mold and a Ni stamper by injection molding is manufactured. The molding material is generally made of polycarbonate, and the Ni stamper to be a mold is manufactured by plating a master produced by lithography. Then, an Ag alloy film is formed on the recording pattern of the produced L0 molded substrate by a film forming apparatus such as sputtering to form the semitransparent reflective film 2. At the same time, an L1 molded substrate to which a pit for L1 has been transferred is produced by injection molding. This is also generally molded with a polycarbonate and a Ni stamper. An Al alloy film is formed on the recording pattern of L1 by a film forming apparatus such as sputtering to form a total reflection film 4. The L1 molded substrate thus prepared is bonded onto the recording pattern of L0 with an ultraviolet curing resin. This adhesive layer becomes the intermediate layer 3 which separates the L0 layer and the L1 layer. Thus, the sample of the two-layered optical disc 10 according to the embodiment of the present invention is completed. In addition to Ag alloy or Al alloy, Ag, Au, Al, Si or the like can be used for the semi-transmissive reflective film 2 or the total reflective film 4.

The sample of the disk completed as described above is fixed to, for example, a spindle motor 63 shown in FIG. 8, and rotates at a predetermined number of rotations. An optical system for condensing laser light on the disc is disposed on the top of the sample disc. The light emitted from the laser diode 79 is collimated by the collimator lens 80, passes through the beam splitter and the λ / 4 wavelength plate, and is condensed on the sample by the objective lens 70. The reflected light from the sample is split by the beam splitter, passes through the detection lens, and enters the light receiver 95 to be a light reception signal. This signal is also supplied to a servo system which causes a current to flow through a drive coil 71 for driving the objective lens 70. In this way, it is possible to image the focused spot on the sample while keeping the distance to the sample constant at all times. The dual-layer optical disc 10 is attached to the optical disc apparatus of FIG. 8 (or the disc drive 30 of FIG. 1) and rotated at a linear speed of 3.49 m / s by a spindle motor. Subsequently, a laser of wavelength 630 nm is turned on to focus on the recording surface of the L0 layer of the two-layer disc. Then, the tracking servo is operated by the DPD method, the DPP method, the PP method or the like so that the beam spot can follow the pit series arranged in a spiral shape. This time I used the DPP method. Next, information is recorded on the pit sequence. The recording used the laser of wavelength 660 nm with which the recording device was attached. The recording power is 60 mW and the bias power is 20 mW. The information to be recorded is output from the signal source and input to the recording device. The light of the recording power is emitted from the laser of the recording apparatus in accordance with the high level and the low level of the recording signal, and the information (mark and space) is recorded on the disk 10.

FIG. 12 is a view showing an example of a reproduction waveform in the case where superimposition information is superimposed later (overwriting not destroying the existing information) on information (superimposed information unrecorded portion) recorded from the beginning of manufacture on the read-only optical disc is there. In the dual-layer optical disc 10 on which information is recorded by the above-described method, the portion irradiated with the recording power has a reflectance higher than that of the unrecorded portion, and the information is recorded at high and low reflectance. As a result, as shown in FIG. 12, the recording location of the superimposition information is distinguished from the non-recording location of the superimposition information and recorded. The reproduction waveform of FIG. 12 has contents corresponding to the light reception signal waveform of FIG. That is, the above-described superposition information can be written or superposed on the ROM disk.

The embodiment described above does not limit the apparatus and method of the present invention. In this embodiment, a two-layer DVD-ROM disk is used. However, if the recording laser wavelength, recording power, bias power, etc. are appropriately selected, a single layer It is possible to record information (superimposed information) also on a DVD-ROM disc and a BD-ROM disc. Furthermore, information can be superimposed also on a writable disc (DVD-R, BD-R, etc.) as shown in FIG. 6 or FIG. 12 by appropriately selecting the recording laser wavelength, recording power, bias power and the like. Further, the recording is not limited to the L0 layer, and recording can be performed also on each layer of the L1 layer and a disc having a multilayer structure. Further, the wavelength of the laser is not limited to 660 nm, and can be applied to, for example, a blue laser of 405 nm. In the present invention, an example in which the recorded portion has a high reflectance has been described, but depending on the material of the reflective layer and on which recording layer the information is recorded, the recorded portion has a lower reflectance than the unrecorded portion. It is also possible to

Although the present invention has been described by way of example applied to a dual layer DVD-ROM, the present invention is not limited to this and can be applied to a single layer DVD-ROM. In addition, although a 660 nm red laser is used as the laser used in the above-described embodiment, a blue laser having a wavelength of 405 nm can also be applied. The present invention is also applicable to a single-layer or two-layer Blue-ray Disc in which a cover layer having a thickness of 0.1 mm is provided on the laser receiving surface side. Furthermore, the present invention can also be applied to an optical disc having a structure of three or more layers, in which case it can be applied to recording using a recording layer other than the recording layer closest to the light incident side.

<Effect of the embodiment>
By implementing the present invention, management copy is realized as well as package media compatible with management copy even from released (distributed) package media (such as DVD video disc) in which identification information required for management copy is not recorded. can do. Specifically, even from the "released read-only optical disc media on which the content is recorded" which is not created on the assumption of the management copy, similarly to the ROM medium in which the unique ID is previously recorded corresponding to the management copy, It becomes possible to manage the number of management copies created from one disk one.

The management copy method, apparatus, and recording medium according to the present invention can be used when copying protected content from a content-recorded medium that has already been distributed to another recording medium or recording apparatus.

Claims

Protected content is content protected by content protection technology, and
The management copy is to make a copy of the protected content under the control of the person having the content copyright or the person who received the permission,
Superimposition information is information indicating that a copy has been created by the management copy, and
When performing management copy of the protected content written at the time of manufacture or preparation of the first information recording medium for which identification information for uniquely identifying each recording medium is not prepared, to the second information recording medium In the method of superimposing or writing the superimposition information on the first information recording medium,
A management copy method, comprising determining permission or rejection of management copy of the protected content based on the superposition information.
The management copy of the protected content is performed using any one of one or more terminal devices and a server connected to the terminal device via a network, and each of the one or more terminal devices performs different predetermined information for each device. In the case of having it, the user writes the predetermined information different for each device as the identification information in the second information recording medium, and relates to the user who performed the management copy using the terminal device connected to the server via the network. The method according to claim 1, wherein user information is registered in the server together with the identification information, and management copy of the protected content is performed while performing user management based on the user information registered in the server.
Protected content is content protected by a predetermined content protection technology, and
The management copy is to make a copy of the protected content under the control of the person having the content copyright or the person who received the permission,
Superimposition information is information indicating that a copy has been created by the management copy, and
A reading module for reading the protected content written at the time of manufacture or preparation of the first information recording medium, in which identification information for uniquely identifying each recording medium is not prepared;
A recording module for recording the protected content read by the reading module on a second information recording medium;
A module for superimposing or writing the superimposition information on the first information recording medium when the protected content is recorded by the recording module;
An apparatus comprising: a writing module for writing predetermined information different for each apparatus to the second information recording medium as the identification information.
A reading module for reading the superposition information from the first information recording medium, an indication whether or not the superposition information has been read by the reading module, and / or an indication for displaying the contents of the superposition information read by the reading module The apparatus of claim 3, further comprising a module.
The first information recording medium used in the management copying method according to claim 1 is a read-only optical disc comprising a substrate on which information in a pit sequence is formed in a spiral in advance and a reflection layer for reflecting a light beam. At this time, the light beam having a larger power than that at the time of reading is condensed on a part of the information recording area formed by the pit series on the first information recording medium, whereby the superimposed information is formed on the pit series A device that overlaps the mark space corresponding to.
The mark / space has a header portion indicating the head position of the superimposition information and information corresponding to a data portion indicating the content of the superimposition information, and the mark / space is formed by ternary frequency shift keying and this ternary value The apparatus according to claim 5, wherein first and second frequencies used in frequency shift keying are assigned to the data portion, and a third frequency used in the ternary frequency shift keying is assigned to the header portion. .
6. The apparatus of claim 5, wherein the light beam is constant amplitude modulated to record the mark space.
The mark space is formed by modulating the light beam at a predetermined modulation carrier frequency, and the upper limit or the maximum value of the modulation carrier frequency is a low frequency band of data recorded in the information recording area formed by the pit series. The apparatus according to claim 5, wherein the lower limit or the minimum value of the modulation carrier frequency is lower than a cut-off frequency, and is higher than an upper limit of a servo band which causes the light beam to trace the pit series.
The first information recording medium used in the management copy method according to claim 1 is an optical disc, and the superimposed information is collected by condensing a light beam having a larger power than that at the time of reading on the information recording area of the disc. Superimposed optical disc.
The optical disc according to claim 9 has a first information recording layer having a semitransparent reflection layer, and a second information recording layer having a reflection layer, and the information formed on the first information recording layer An optical disc on which the superposition information is superposed by condensing the light beam on a recording area.