JP4449175B2 - Optical disc apparatus, optical disc recording method, optical disc, and optical disc reproduction method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical disc apparatus, an optical disc recording method, an optical disc, and an optical disc reproduction method, and can be applied to a system using, for example, a mini disc (MD), a digital video recorder (DVR), or the like. The present invention combines a plurality of systems of signals generated by disturbing each bit string of the first information related to copyright into a single system based on a pseudorandom number corresponding to the second information related to copyright. By generating this, it is possible to protect the interests of the copyright holder more effectively than in the past.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, mini-disc devices, which are optical disc devices, have been rapidly spreading in recent years because music can be easily copied from various contents while preventing deterioration of sound quality. In other words, in a minidisc device, music information distributed over the Internet can be recorded on a minidisc and auditioned, and music on a compact disc borrowed from a friend or the like can be recorded on the minidisc and auditioned. You can also copy music from other minidiscs.
[0003]
However, simple copying that prevents such deterioration in sound quality greatly increases the convenience for the user, but may also impair the profits of the copyright holder who created the music. For this reason, various methods are being studied for the purpose of protecting the interests of copyright holders in organizations such as RIAA (Recording Industry Association of America), SDMI (Secure Digital Music Initiative), and CPTWG (Copy Protection Technical Working Group). It is made to be done.
[0004]
As one of such methods, a method has been proposed in which music information is encrypted and recorded with copyright protection information unique to the recording medium. In other words, according to this method, when music information is copied to another recording medium, it is difficult to release encryption due to different copyright protection information on the recording medium, thereby preventing unlimited copying. To protect the interests of copyright holders.
[0005]
As for such a copyright protection information recording method, a sector that is difficult for the user to access is provided and the copyright protection information is recorded in this sector, and the reflective film is partially applied to the main data recording by the pit row. And a method of recording this kind of information in the form of a bar code (International Publication No. WO 97/14144) has been proposed.
[0006]
[Problems to be solved by the invention]
However, these methods still have insufficient practical problems in terms of effectively protecting the interests of the copyright holder.
[0007]
In other words, in the method of providing a sector that is difficult for the user to access and recording the copyright protection information in this sector, the copyright protection information can be recorded relatively easily, but the copyright protection information is copied accordingly. There is a problem that is easy to be done.
[0008]
In addition, the method of recording this type of information in the form of a barcode by partially removing the reflective film has a problem that the recording of this type of information can be confirmed and observed by observation with a microscope or the like, and so-called pirated copies cannot be completely prevented. is there. In addition, instead of removing the reflective film, a method of recording this kind of information in the same manner by creating a partially opaque film on the surface of the optical disk is also conceivable. In this case, however, the reflective film is partially removed. There is a problem similar to that.
[0009]
The present invention has been made in view of the above points, and proposes an optical disc apparatus, an optical disc recording method, an optical disc, and an optical disc reproduction method that can protect the interests of the copyright holder more effectively than in the past. It is something to try.
[0010]
[Means for Solving the Problems]
In order to solve such a problem, the invention of claim 1 is applied to an optical disc apparatus and has a sequence corresponding to the number of bits of the first information related to copyright, compared to the transmission speed of the first information related to copyright. A plurality of binary number generating means for generating a binary number sequence at a fast transmission rate, and a plurality of calculating means for calculating the binary number series with corresponding bits of the first information relating to copyright and outputting a plurality of calculation results And random number generating means for generating pseudo-random numbers according to the second information relating to copyright, and selection means for outputting a drive signal by selectively outputting a plurality of calculation results according to the pseudo-random numbers. .
[0011]
Further, in the invention of claim 7, when applied to an optical disk recording method, each bit string of the first information relating to the copyright differs depending on the transmission speed that is higher than the transmission speed of the first information relating to the copyright. A plurality of systems of signals are generated by perturbing each of the base numbers, a pseudo-random number is generated according to the second information relating to the copyright, and a plurality of systems of signals are selected by the pseudo-random number to generate a single-system drive signal .
[0012]
Further, in the invention of claim 8, when applied to an optical disc, each bit string of the first information related to the copyright is expressed by a binary number sequence having a higher transmission speed than the transmission speed of the first information related to the copyright. After each disturbance, a pit row or a mark row is created by a drive signal created in one system based on a pseudo-random number corresponding to the second information related to copyright.
[0013]
According to a thirteenth aspect of the present invention, the first decryption means for decrypting the first information relating to the copyright from the reproduction signal, and each bit string of the first information relating to the copyright, applied to the optical disc apparatus, Signal predicting means for generating a predicted reproduction signal in a single system based on a predetermined pseudo-random number after being disturbed by different binary sequences at a transmission rate faster than the transmission rate of the first information relating to the right; The second decoding means for decoding the second information related to the copyright based on the determination result by determining the logical value corresponding to the pseudo-random number based on the comparison result between the reproduction signal and the predicted reproduction signal. Be prepared.
[0014]
In the invention of claim 18, the present invention is applied to an optical disc reproducing method, and first information related to copyright is decoded from the result of receiving the return light, and based on the decoding result of the first information related to copyright. Then, a light reception result based on the prediction of the second information related to the copyright is generated, and the second information related to the copyright is decoded by comparing the light reception result based on the prediction with the light reception result of the return light.
[0015]
According to the configuration of claim 1, when applied to the optical disc apparatus, the sequence corresponding to the number of bits of the first information related to copyright is faster than the transmission rate of the first information related to copyright. A plurality of binary number generating means for generating a binary number series, a plurality of calculating means for calculating the binary number series with corresponding bits of the first information relating to copyright, and outputting a plurality of calculation results; A pit string or mark string is provided by including a random number generating means for generating a pseudo random number according to the second information and a selecting means for outputting a drive signal by selectively outputting a plurality of calculation results according to the pseudo random number. Thus, the first and second information relating to the copyright can be recorded on the optical disc, making it difficult to find and analyze them. In addition, since one bit of the information can be allocated and recorded at a relatively long distance in the circumferential direction, it is possible to reproduce the information while effectively avoiding the influence of noise, scratches, and the like. In addition to this, each bit of the first information related to copyright does not affect the decoding by the other binary number sequences in the process of generating the drive signal, and the corresponding binary number sequence is used. Otherwise, it is difficult to decode, and thus, even when tracking control is difficult due to recording of other information using a barcode or the like, it is possible to reproduce correctly. Thus, by using the first and second information relating to the copyright to restrict access to the optical disc, the interest of the copyright holder can be protected more effectively than in the past.
[0016]
Thereby, according to the structure of Claim 7, it can apply to the recording method of an optical disk, and can protect the profit of a copyright holder more effectively compared with the past.
[0017]
According to the configuration of claim 8, when applied to an optical disc, it is possible to protect the interests of the copyright holder more effectively than in the past.
[0018]
According to the configuration of the thirteenth aspect, the first decoding means for decoding the first information about the copyright from the reproduction signal and each bit string of the first information about the copyright are applied to the optical disc apparatus, Signal predicting means for generating a predicted reproduction signal collectively in one system based on a predetermined pseudo-random number after being disturbed by different binary numbers at a transmission speed higher than the transmission speed of the first information relating to the right; The second decoding means for decoding the second information related to the copyright based on the determination result by determining the logical value corresponding to the pseudo-random number based on the comparison result between the reproduction signal and the predicted reproduction signal. In this manner, a plurality of signals generated by disturbing each bit of the first information on the copyright are collectively recorded in one system using a pseudo random number, and a work corresponding to the pseudo random number is recorded. It is possible to decode a second information about. Therefore, it is possible to use the second information related to copyright recorded as difficult to find and analyze, for example, for identifying the manufacturing equipment of the optical disc, thereby protecting the interests of the copyright holder more effectively than before. can do.
[0019]
Thereby, according to the structure of Claim 18, it can apply to the reproducing method of an optical disk, and can protect the profit of a copyright holder more effectively compared with the past.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
[0021]
(1) Configuration of the embodiment
FIG. 2 is a process diagram showing an optical disk manufacturing process according to the embodiment of the present invention. In this embodiment, the optical disc manufacturing process 1 records three types of copyright protection information SA, SB, and SC to manufacture a mini-disc 2.
[0022]
Here, among these three types of copyright protection information SA to SC, the first and third copyright protection information SA and SC are used in combination to encrypt audio data and the like recorded on the mini-disc 2; Also, it is key information used for decrypting audio data recorded on the mini disc 2, and an arbitrary random number unique to the mini disc 2 is applied. On the other hand, the second copyright protection information SB is information that can be used to pursue the origin of the mini-disc when an illegal mini-disc is distributed, and is used to specify the manufacturer of the mini-disc. Information. The second copyright protection information SB is assigned, for example, information such as a device number unique to the cutting machine, information related to the manufacturing factory, and manufacturing date.
[0023]
As shown in FIG. 3, the information recording surface of the mini-disc 2 is concentrically divided, and the inner peripheral area is assigned to the copyright information recording area 3 and the outer peripheral area is assigned to the user data recording area 4. The mini-disc 2 is configured such that these three types of copyright protection information SA to SC are recorded in the copyright information recording area 3 and audio data and the like can be recorded in the user data recording area 4. Further, in this copyright information recording area 3, on the mini-disc 2, the copyright protection information SA and SB are repeatedly recorded by a pit row, and the recording film changes overlapping the recording of the copyright protection information SA and SB. Thus, the copyright protection information SC is recorded in the form of a barcode. In the user data recording area 4, the mini-disc 2 is formed such that a groove which is a guide groove of the laser beam snakes according to address information in the same manner as a normal mini-disc, and a lead-in area or the like is created. Has been made.
[0024]
Therefore, in this optical disc manufacturing process 1 (FIG. 2), the signal sources 6A and 6B repeatedly supply copyright protection information SA and SB to the cutting machine 7, respectively.
[0025]
The cutting machine 7 modulates the recording laser beam with the copyright protection information SA and SB and irradiates the disc master 8, and instead modulates the recording laser beam with predetermined position information to disc the disc master. 8 is irradiated. As a result, the cutting machine 7 exposes the disc master 8, records the copyright protection information SA by a pit string, and further records the groove, lead-in area, and the like.
[0026]
In the optical disk manufacturing process 1, the subsequent developing process 9 develops the disk master 8 exposed by the cutting machine 7 in this way, and forms fine irregularities corresponding to pit rows and grooves on the exposure locus.
[0027]
In the subsequent plating step 10, the disk master 8 is subjected to a plating process, thereby creating a mother disk 12. The optical disk manufacturing process 1 creates a stamper from the mother disk 12, and the injection molding process 13 copies the fine irregularities formed on the mother disk 12 by attaching the stamper to an injection molding machine and performing injection molding. The disk substrate 14 is mass-produced.
[0028]
In the subsequent recording film generating step 15, a recording film made of a magneto-optical film is formed on the disk substrate 14 by a technique such as sputtering.
[0029]
The signal source 16 outputs the copyright protection information SB to the barcode writing device 17, and the barcode writing device 17 changes the recording film of the disk substrate 14 with the copyright protection information SC to copy the copyright in the form of a barcode. Record the protection information SC. Here, the barcode writing device 17 is mounted on the area where the copyright protection information SA and SB are recorded while the mini-disc 2 formed with a recording film is mounted and rotationally driven, for example, YAG (yttrium, aluminum, Garnet) A high-power laser beam from a laser or the like is modulated by the copyright protection information SC and irradiated in synchronism with the rotation of the mini disk 2 to partially change the reflectance of the recording film, thereby changing the barcode. The copyright protection information SC is recorded in the form. When the copyright protection information SC is recorded in the form of a barcode due to such a change in the recording film, a carbon dioxide laser, a high-power semiconductor laser, or the like can be used instead of the YAG laser.
[0030]
In the optical disk manufacturing process 1, a protective film is formed on the recording film in the subsequent protective film forming process 18, whereby the mini disk 2 is completed.
[0031]
FIG. 4 is a block diagram showing the cutting machine 7. The cutting machine 7 records the copyright protection information SA and SB on the disc master 8 in the form of pits, and records the groove, lead-in area, etc. on the disc master 8.
[0032]
That is, in the cutting machine 7, the spindle motor 20 rotates the disk master 8 at a predetermined rotational speed under the control of the spindle servo circuit 21, and the disk master 8 is rotated by a predetermined angle from the FG signal generator held at the bottom. The FG signal FG whose signal level rises every time is output. The spindle servo circuit 21 controls the operation of the spindle motor 20 so that the master disk 8 rotates at a predetermined rotational speed with reference to the FG signal FG.
[0033]
The laser light source 23 is constituted by, for example, a gas laser or the like, and emits a recording laser beam L 1 toward the optical modulator 24.
[0034]
The optical modulator 24 is configured by an electroacoustic optical element or the like, and modulates the recording laser beam L1 with the drive signal SD to emit the laser beam L2. In this modulation, the optical modulator 24 switches the operation under the control of the central processing unit 22 and is driven during the period in which the copyright protection information SA and SB, information necessary for creating the lead-in area, etc. are recorded. While the laser beam L1 is modulated by on / off control in accordance with the signal SD, the laser beam L1 is modulated by changing the emission direction in accordance with the drive signal SD during the groove recording period.
[0035]
The mirror 25 bends the optical path of the laser beam L2 and emits it toward the disc master 8. The objective lens 26 condenses the reflected light of the mirror 25 on the recording surface of the disc master 8. The mirror 25 and the objective lens 26 are sequentially moved in the radial direction in synchronization with the rotation of the disk master 8 by a thread mechanism (not shown). Thereby, in the cutting machine 7, the condensing position of the laser beam L2 is sequentially displaced in the outer peripheral direction of the disk master 8, and a spiral track is formed on the disk master 8. Further, in the copyright information recording area 3, a pit string corresponding to the drive signal SD is created on this track to record the copyright protection information SA and SB, and similarly, the lead-in area and the like are recorded. In the user data recording area 4, address information is recorded by meandering of the groove corresponding to the drive signal SD.
[0036]
Therefore, the modulation circuit 27 receives the copyright protection information SA and SB from the signal sources 6A and 6B, modulates the copyright protection information SA and SB, and outputs a modulation signal SX.
[0037]
The address format signal generating circuit 28 generates address information and format information necessary for the lead-in area and the user data recording area 4, and generates a wobble signal or the like whose signal level changes according to the meandering of the groove. Output.
[0038]
The data selector 29 selects the modulation signal SX output from the modulation circuit 27 and the output signal of the address format signal generation circuit 28 under the control of the central processing unit 22 and outputs the drive signal SD. The central processing unit 22 constitutes a control circuit for controlling the operation of the cutting machine 7, detects the irradiation position of the laser beam L2 by the monitor of the sled mechanism that drives the mirror 25 and the objective lens 26, and the detection result indicates data. The operation of the selector 29, the optical modulator 24, etc. is switched and controlled.
[0039]
FIG. 1 is a block diagram showing the modulation circuit 27, and FIG. 5 is a signal waveform diagram for explaining the operation of the modulation circuit. The modulation circuit 27 generates the modulation signal SX by processing the copyright protection information SA and SB with reference to the FG signal FG. Here, the PLL circuit 41 operates on the basis of the FG signal FG to generate a channel clock CK (FIG. 5A) synchronized with the rotation of the disk master 8, and supplies it to each part of the modulation circuit 27.
[0040]
The timing generator (TG) 42 counts the channel clock CK to generate an initialization pulse SY that initializes the M series generation circuits 45A to 45D at predetermined time intervals. The timing generator 42 generates and outputs a synchronization pattern selection signal ST synchronized with the initialization pulse SY. In this embodiment, the initialization pulse SY is generated so as to rise by one clock width in synchronization with the channel clock CK (FIG. 5B). Further, the synchronization pattern selection signal ST is generated so as to rise with a width of 5 clocks from the rising timing of the initialization pulse SY (FIG. 5C).
[0041]
Here, in the modulation circuit 27, the copyright protection information SA and SB are input in a 4-bit parallel at a bit rate based on the period of the initialization pulse SY that is much slower than the channel clock CK generated in this way. It is made so that.
[0042]
The synchronization pattern generation circuit 43 generates and outputs a predetermined synchronization pattern DY with reference to the rising edge of the initialization pulse SY. In this embodiment, as shown in FIG. 5D, the synchronization pattern DY is set such that the logical value becomes “11011” in a period of 5 clock cycles from the rising edge of the initialization pulse SY.
[0043]
The M series generation circuits 45A to 45D are initialized by the initialization pulse SY, and output M series M1 to M4 that change in units of the channel clock CK (FIGS. 5E to 5H). Here, the M series M1 to M4 are data strings in which logical values change randomly and the occurrence probabilities of logic 1 and logic 0 are equal probabilities. In this embodiment, the M series M1 to M4 are synchronized with the channel clock CK. Except for the point of change, M sequences M1 to M4 exhibiting changes that are not related to each other (so-called uncorrelated) are applied.
[0044]
As a result, the M-sequence generation circuits 45A to 45D generate a binary sequence at a higher transmission rate than the transmission rate of the copyright information by the sequence corresponding to the number of bits of the copyright protection information SA, which is information related to the copyright. A plurality of binary sequence generating means for generating is configured, and a binary sequence is repeatedly output based on the synchronization pattern.
[0045]
Arithmetic circuits (X) 46A to 46D are configured by exclusive OR circuits, respectively, and perform exclusive OR operations on the M series signals M1 to M4 and the bits b0 to b3 of the copyright protection information SA, respectively. Output. Thereby, the modulation circuit 27 disturbs one bit of the copyright protection information SA by the M series signals M1 to M4. At this time, by applying so-called uncorrelated M-sequence signals M1 to M4, even when the logical values of the bits b0 to b3 are the same, the calculation results are different, and the bits b0 to b3 are decoded. In addition, they are processed by the M series signals M1 to M4, respectively, so that they are not affected by the calculation results of the other bits b0 to b3. Thus, the arithmetic circuits 46A to 46D constitute a plurality of arithmetic means for calculating the binary number sequence by the M sequence generating circuits 45A to 45D with the corresponding bits of the copyright protection information SA and outputting a plurality of calculation results.
[0046]
The random number generation circuit 47 generates a 2-bit random number (a random number having a value of 0, 1, 2, or 3) R in units of channel clock CK according to the copyright protection information SB (b4 to b7). Then, the data is output to the data selector 48 (FIG. 5I). Similarly to the M series generation circuits 45A to 45D, the pseudo random number R is reset and generated by the initialization pulse SY.
[0047]
The data selector 48 selectively outputs the calculation results of the calculation circuits 46A to 46D according to the value of the 2-bit random number R. That is, when the output of the random number generation circuit 47 is 0, the output of the first arithmetic circuit 46A is selected, whereas when the output of the random number generation circuit 47 is the value 1, 2, or 3, the arithmetic circuits 46B and 46C, respectively. , 46D output is selected.
[0048]
As a result, the modulation circuit 27 converts the calculation results obtained by the calculation circuits 46A to 46D into the copyright protection information SB in a state in which the decoding is based on the corresponding M series M1 to M4 and is not affected by other calculation results. The system is further disturbed in a single system by random numbers corresponding to the above.
[0049]
The data selector 49 selects and outputs the synchronization pattern DY output from the synchronization pattern generation circuit 43 and the output of the data selector 48 with reference to the synchronization pattern selection signal ST. As a result, the modulation circuit 27 selects and outputs the output of the data selector 48 after the synchronization pattern of logic “11011” appears for a period of 5 clock cycles after the initialization pulse SY rises. (FIG. 5 (J)).
[0050]
Thus, in the master disc 8, a pit P corresponding to the output signal SX of the modulation circuit 27 is created in the copyright information recording area 3 (FIG. 5 (K)). In FIG. 5, FIGS. 5L to 5N are diagrams showing generation of the modulation signal SX and the pit P in different periods with the initialization pulse SY as a reference. In this embodiment, four systems are used by a random number R corresponding to the copyright protection information SB. Calculation By disturbing the results together in one system, as shown in FIGS. 5L to 5N, the logical value of the first copyright protection information SA in the pit sequence recorded on the master disc 8 is shown. Even if they are the same, if the second copyright protection information SB is different, a different change is exhibited. Thus, in this embodiment, the copyright protection information SA is difficult to find and analyze.
[0051]
The modulation circuit 27 is set so that the pits based on the synchronization pattern overlap with each other on the inner and outer circumferences of the mini-disc 2 by selecting the generation cycle of the synchronization pattern selection signal ST and the number of bytes of the copyright protection information SA (FIG. 3). (B)). That is, as viewed from the rotation center of the mini-disc 2, the information recording surface of the mini-disc 2 is divided at a predetermined angular interval, and a synchronization pattern is recorded in a predetermined range from the top side of the divided area. As a result, one bit of information relating to copyright is recorded on the mini-disc 2 in a distributed manner in the circumferential direction of the information recording surface.
[0052]
FIG. 6 is a block diagram showing an optical disc apparatus for recording / reproducing the mini disc 2 created as described above. In the optical disk device 61, the spindle motor 62 rotates the mini disk 2 at a predetermined rotational speed under the control of the servo circuit 65.
[0053]
The optical pickup 63 is held by a predetermined thread mechanism so as to be movable in the radial direction of the mini disk 2. The optical pickup 63 irradiates the mini-disc 2 with a laser beam, receives the return light, and outputs a light reception result. Further, during recording, the optical pickup 63 applies a modulation magnetic field by intermittently raising the light amount of the laser beam from the light amount at the time of reproduction to the light amount at the time of recording, whereby various information is recorded by thermomagnetic recording by a so-called pulse train method. To do.
[0054]
The matrix amplifier (MA) 64 processes the output signal of the optical pickup 63 to thereby process a wobble signal whose signal level changes according to the meandering of the groove, and a tracking error signal TK whose signal level changes according to the amount of tracking error. A focus error signal FS whose signal level changes according to the amount of focus error, a reproduction signal MO whose signal level changes according to the polarization plane of the return light from the mini disk 2 by using the magnetic Kerr effect, and recording on the mini disk 2 A reproduction signal HF whose signal level changes according to the change of the film and the pit row is generated and output.
[0055]
The servo circuit 65 performs tracking control and focus control of the optical pickup 63 by using the tracking error signal TK and the focus error signal FS. The servo circuit 65 controls the rotation speed of the spindle motor 62 so that the clock generated from the wobble signal has a predetermined frequency. Further, address information is acquired from the wobble signal, and the optical pickup 63 is sought to a predetermined position under the control of a central processing unit (CPU) 66.
[0056]
The analog-digital conversion circuit (AD) 67 sequentially performs analog-digital conversion processing on the reproduction signal HF in a cycle sufficiently shorter than the above-described channel clock CK, and outputs an 8-bit digital reproduction signal DX. The second decoding circuit 68 processes the digital reproduction signal DX obtained from the copyright information recording area 3 to decode and output the copyright protection information SA.
[0057]
The central processing unit 66 constitutes a control circuit for controlling the operation of the optical disc device 61. When the loading of the mini disc 2 is detected through a mini disc detection mechanism (not shown), the central processing unit 66, like a normal mini disc device, The optical pickup 63 is sought to the lead-in area under the control of the servo circuit 65, and TOC data necessary for accessing the mini disk 2 is acquired. Subsequently, the optical pickup 63 is sought in the copyright information recording area 3 and the copyright protection information SA is obtained from the second decoding circuit 68. At this time, since the copyright protection information SC is recorded on the mini-disc 2 by the barcode and tracking control is difficult in the copyright information recording area 3, the central processing unit 66 stops the tracking control operation and focuses. The servo circuit 65 is instructed to access only by the control state.
[0058]
Thus, when acquiring the copyright protection information SA from the second decoding circuit 68, the central processing unit 66 reproduces the copyright protection information SB by processing the digital reproduction signal DX together. That is, the central processing unit 66 binarizes the digital reproduction signal DX based on a predetermined threshold value, and reproduces a clock used for recording the copyright protection information SB from the binarization result. Further, the central processing unit 66 generates the reproduction data by sequentially latching the binarization result with reference to this clock. The central processing unit 66 reproduces the copyright protection information SB recorded by the barcode by performing error correction processing or the like on the reproduced data in accordance with the processing at the time of recording as necessary.
[0059]
As a result, when the reproduction instruction of the mini-disc 2 is instructed by the user, the central processing unit 66 generates information necessary for decryption by using these two copyright protection information SA and SB and drives the reproduction system. On the other hand, when recording to the mini-disc 2 is instructed, information necessary for the encryption process is generated in the same manner to drive the recording system.
[0060]
In the reproduction system that operates under the control of the central processing unit 66 in this way, the decoding circuit 69 processes the reproduction signal MO to reproduce the clock in the same manner as the decoding circuit in a normal mini-disc device, and further reproduces this clock. The reproduction signal MO is demodulated on the basis of EFM (Eight to Fourteen Modulation) and reproduction data is output.
[0061]
The decryption circuit 79 decrypts the reproduction data based on the copyright protection information SA and SC and outputs the decrypted data. An error correcting circuit (ECC) 71 performs error correction processing on the output data of the decryption circuit 79 and outputs the data. Such an error is caused by, for example, a defect on the mini disk 2 or the like. As a result, the optical disc device 61 reproduces and outputs audio data and the like by the encryption processing unique to the mini disc 2 based on the copyright protection information SA and SC.
[0062]
On the other hand, in the recording system, an error correcting circuit (ECC) 72 adds an error correcting code to the sequentially input data and outputs the data, and the subsequent encryption circuit 73 outputs copyright protection information SA. The output data of the error correction circuit 72 is encrypted and output with reference to SC. The modulation circuit 74 modulates the output data of the encryption circuit 73 by EFM (Eight to Fourteen Modulation) to generate a modulation signal, and drives the modulation coil of the optical pickup 63 by this modulation signal. As a result, the optical disc device 61 is configured to encrypt and record the audio data and the like by the encryption processing inherent to the mini disc 2 based on the copyright protection information SA and SC.
[0063]
FIG. 7 is a block diagram showing a second decoding circuit for decoding the copyright protection information SA from the digital reproduction signal DX. In the second decoding circuit 68, the PLL circuit 81 reproduces the channel clock CK generated at the time of recording with reference to the digital reproduction signal DX, and outputs it to each part.
[0064]
The synchronization detection circuit 82 detects the synchronization pattern by identifying the digital reproduction signal DX based on the channel clock CK, and reproduces the initialization pulse SY at the time of recording from the detection result.
[0065]
The M series generation circuits 83A to 83D output the M series M1 to M4 generated at the time of recording with reference to the initialization pulse SY and the channel clock CK.
[0066]
Exclusive or The circuits (X) 84A to 84D respectively receive the M series signals M1 to M4 and the digital reproduction signal DX. Exclusive OR processing do it Calculation Output the result.
[0067]
Here, in the access to the copyright information recording area 3, tracking control is difficult, so the digital reproduction signal DX can be obtained by scanning a plurality of tracks in a meandering manner. As a result, in the digital reproduction signal DX, the output signal SX of the modulation circuit 27 recorded on a plurality of tracks is reproduced in a further disturbed format. On the other hand, in the copyright protection information SA, the output signal SX of the modulation circuit 27 is not affected by other calculation results by decoding based on the corresponding M series M1 to M4. The calculation results of the four systems are disturbed by the random number R and are combined into one system. As a result, in the digital reproduction signal DX, the output signal SX of the modulation circuit 27 assigned to each track is further reproduced by scanning the mini-disc 2 and being disturbed by the bar code. It can be correctly reproduced only by decoding based on the sequences M1 to M4.
[0068]
Thereby, the integration circuits 85A to 85D Exclusive or Output from the circuits 84A to 84D Calculation By integrating the results with reference to the initialization pulse SY, an integration result having a value corresponding to the logical values of the corresponding bits b0 to b3 of the copyright protection information SA is output. The determination circuits 86A to 86D respectively decode the bits b0 to b3 of the copyright protection information SA by identifying the integration results output from the integration circuits 85A to 85D in binary with reference to the initialization pulse SY. Output.
[0069]
As a result, in the optical disc device 61, the optical pickup 63 and the matrix amplifier 64 constitute reproduction signal generation means for generating a reproduction signal, whereas the PLL circuit 81, the synchronization detection circuit 82, and the M series generation circuits 83A to 83B A binary number sequence generating means for generating a plurality of binary number sequences on the basis of the synchronization pattern of the reproduction signal is configured. Also Exclusive or Circuits 84A-84D are each binary sequences To process the exclusive OR operation of the playback signal, The integrating circuits 85A to 85D are This operation A plurality of integration means for integrating the results and outputting a plurality of integration results are configured, and the determination circuits 86A to 86D configure determination means for determining the integration results and decoding the corresponding bit strings of the copyright protection information. It is made like that.
[0070]
FIG. 8 is a block diagram showing an optical disc inspection apparatus that reproduces the second copyright protection information SB. This optical disk inspection device 90 is used for specifying an unauthorized use of the cutting machine 7 or the like. In the configuration shown in FIG. 8, the same configuration as the optical disc device 61 described above with reference to FIG. With the configuration common to the optical disc device 61, the optical disc inspection device 90 reproduces the first copyright protection information SA by the second decryption circuit 68.
[0071]
The modulation circuit 93 is configured in the same manner as the modulation circuit 27 of the cutting machine 7, and the first copyright protection information SA reproduced by the second decoding circuit 68 and the copyright protection information SB output from the central processing unit 94. The modulation signal SXX is generated from the predicted value SBX.
[0072]
The binarization circuit 95 binarizes the reproduction signal HF with a predetermined threshold value, thereby generating a binarization signal corresponding to the pit string created on the mini disk 2. As a result, the binarization circuit 92 reproduces the modulation signal SX generated by the cutting machine 7.
[0073]
The exclusive OR circuit 96 generates a calculation signal based on the exclusive OR of these two modulation signals SX and SXX, and outputs a comparison result between the two modulation signals SX and SXX.
[0074]
When the reproduction of the copyright protection information SB is instructed, the central processing unit 94 causes the optical pickup 63 to seek the copyright information recording area 3 of the mini-disc 2 under the control of the servo circuit 65, and the second decoding circuit 68 performs the work. The right protection information SA is acquired. At this time, the central processing unit 94 operates the servo circuit 65 so as to scan the same track even when the tracking servo is disturbed by the barcode-like recording of the copyright protection information SC in the copyright information recording area 3. To control.
[0075]
Further, the central processing unit 94 sequentially switches and outputs the predicted value SBX of the copyright protection information SB in a state where scanning of the same portion is repeated in this manner, and the exclusive OR circuit 96 is interlocked with this switching. Reset the total of comparison results obtained.
[0076]
That is, in the case where the modulation signal SXX is generated by the modulation circuit 93 in this way, when the predicted value SBX of the copyright protection information SB matches the copyright protection information SB recorded on the minidisc 2, The modulation signal SXX obtained from the modulation circuit 93 coincides with the modulation signal SX obtained from the mini disk 2. Since the copyright protection information SC is recorded in a barcode form on the mini-disc 2, the modulation signal SX obtained from the mini-disc 2 affects the recording of the copyright protection information SC in the form of a barcode. Although received, in the copyright protection information SB, 1 bit is distributed and recorded at a relatively long distance in the circumferential direction of the mini-disc 2. Therefore, the predicted value SBX of the copyright protection information SB from which the counting result with the highest matching probability is obtained can be determined as the copyright protection information SB.
[0077]
As a result, the central processing unit 94 determines the predicted value SBX having the highest matching probability from the tabulation results thus obtained as the copyright protection information SB. Accordingly, the central processing unit 94 sequentially determines each logical value of the 4-bit parallel copyright protection information SB by repeating the process by sequentially displacing the laser beam irradiation position in the copyright information recording area 3. Thus, the copyright protection information SB is decrypted.
[0078]
(2) Operation of the embodiment
In the above configuration, in the manufacturing process of the mini-disc 2 (FIG. 2), by exposing and developing the disc master 8 with the cutting machine 7, fine irregularities created on the mini-disc 2 are created on the disc master 8. A disk substrate 14 of the mini disk 2 formed by transferring the fine irregularities through the plating step 10 or the like is created, and a recording film and a protective film are formed on the disk substrate 14 to produce the mini disk 2.
[0079]
In the mini-disc 2 created in this way (FIGS. 3 and 4), in the lead-in area, the user data recording area 4 and the like, the drive signal SD is created by the output signal of the address format signal generation circuit 28. The recording laser beam L1 is modulated by the optical modulator 24 by the drive signal SD, and the disc master 8 is exposed, so that the disc is produced in the same manner as the conventional mini disc 2. On the other hand, in the copyright information recording area 3 on the inner circumference side of the mini-disc 2, the recording laser is generated by the drive signal SD generated by modulating the copyright protection information SA, which is information related to the copyright, by the modulation circuit 27. The beam L1 is subjected to on / off modulation, whereby copyright protection information SA is recorded in the copyright information recording area 3 by a pit string.
[0080]
This copyright protection information SA (FIGS. 1 and 5) is input to the modulation circuit 27 by 4-bit parallel, where each bit has a transmission speed higher than that of the first copyright protection information SA and is different from each other. 4 series M series M1 to M4 are generated by the M series generation circuits 45A to 45D, and each of the M series M1 to M4 and the corresponding bits b0 to b3 are arithmetically processed by the arithmetic circuits 46A to 46D. As a result, the first copyright protection information SA is disturbed by the M series M1 to M4, which are binary series, and is difficult to find.
[0081]
Further, the first copyright protection information SA is selected and output by the data selector 48 based on the random number R as a result of the operation of the operation circuits 46A to 46D, and is further disturbed and converted into a drive signal by one system. It is even more difficult to find.
[0082]
In the first copyright protection information SA, a sync pattern DY is inserted into the output signal of the data selector 48 by the data selector 49, thereby generating M sequences M1 to M4 on the basis of the sync pattern DY during reproduction. The bits b0 to b3 can be reproduced by decoding based on the generated M sequences M1 to M4.
[0083]
In other words, in the M sequences M1 to M4, the signals disturbed by the other M sequences M1 to M4 are decoded by a desired M sequence because the logic 1 and the logic 0 are generated with equal probability regardless of each other. When the decoding result is viewed over a long period of time, it converges to an average value of signal levels corresponding to logic 1 and logic 0. On the other hand, when decoding is performed using the corresponding M sequence M1 and the same determination is made, the correct logic level can be determined.
[0084]
As a result, in this embodiment, each bit string of copyright information is disturbed by different binary sequences to generate a plurality of systems of signals, and the plurality of systems of signals are further disturbed to generate a system of driving signals. By generating and modulating the laser beam, copyright protection information SA is recorded by an irregular arrangement of pits, thereby making it difficult to find copyright protection information.
[0085]
Furthermore, by disturbing the four systems in this way and recording them together in one system, one bit of the first copyright protection information SA is distributed and recorded over a relatively long distance of one track. ing.
[0086]
In this way, when recording the first copyright protection information SA, the modulation circuit 27 generates a pseudo-random number R when the four signals are combined into one system in accordance with the second copyright protection information SB. Generated. As a result, in this embodiment, in addition to the first copyright protection information SA, the second copyright protection information SB is also distributed and recorded over a relatively long distance of one track so that it is difficult to find and analyze. can do.
[0087]
Here, also in the pseudo-random number R, since the occurrence probability is equal to the logic 1 and the logic 0, the logical value of each bit of the first copyright protection information SA recorded in this way is thus the second. Even when the random number R is switched by the copyright protection information SB, the correct logic level is determined only when the decoding is performed by the corresponding M sequence M1 without affecting the decoding by the different M sequence. Is recorded so that
[0088]
As a result, the mini-disc 2 records the copyright protection information SA and SB as described above, and further records the third copyright protection information SC by a bar code, thereby reproducing the reproduction signal for the copyright protection information SA and SB. Even if the information is temporarily interrupted, the copyright protection information SA and SB can be reliably reproduced.
[0089]
Accordingly, in the optical disc manufacturing process 1 (FIG. 2), after the recording film is formed on the disc substrate 14 in which such fine asperities are created by the copyright protection information SA and SB, the third copyright protection is performed. The recording laser beam modulated by the information SC is irradiated to the area where the copyright protection information SA and SB are recorded, and thereby the copyright protection information SC by barcode is recorded on the copyright protection information SA and SB. .
[0090]
Thereby, the minidisc 2 can make it difficult to find the copyright protection information SA and SB even by recording the copyright protection information SC. Further, since this copyright protection information SC is recorded in the form of a barcode, tracking control can be made difficult. As a result, when the copyright information recording area 3 is accessed for the purpose of analyzing the copyright protection information SA and SB, it is possible to make it difficult to obtain a reproduction signal corresponding to the pit string, and this further protects the copyright. Information SA and SB can be found difficult to analyze.
[0091]
In the mini-disc 2, it is possible to eliminate illegal copying by the encryption processing by the first and third copyright protection information SA and SC recorded in this way.
[0092]
In other words, in the mini-disc 2 (FIG. 6), in the optical disc apparatus 61, the light reception result of the return light obtained from the optical pickup 63 is processed by the matrix amplifier 64 without performing the tracking control, and a signal corresponding to the pit row and bar code The reproduction signal HF whose level changes is detected, the reproduction signal HF is converted into a digital reproduction signal DX having a high sampling rate and processed by the second decoding circuit 68, whereby the copyright protection information recorded by the pit string is recorded. SA is played back. Further, the copyright protection information SC is reproduced by the barcode by the processing of the digital reproduction signal DX in the central processing unit 66.
[0093]
Thereby, in the mini-disc 2, the input data is encrypted and recorded based on the copyright protection information SA and SC, and the reproduction data is decrypted based on the copyright protection information SA and SC. Here, for example, when it is difficult to correctly reproduce the copyright protection information SA and SC, it is difficult to correctly record and reproduce the data by such encryption. Desired data can be correctly recorded and reproduced only for the recorded mini-disc. Thus, in this embodiment, the market value of so-called pirated minidiscs can be significantly reduced, and pirated minidiscs can be excluded from the market.
[0094]
The copyright protection information SA and SC, which are such preconditions, are difficult to find as described above. In particular, the copyright protection information SA is difficult to track. SA and SC itself can also be difficult to copy and analyze, so that pirated copies obtained by copying copyright protection information SA and SC can also be effectively excluded.
[0095]
Accordingly, in the second decoding circuit 68, the digital reproduction signal DX is generated by the M series generation circuits 83A to 83D based on the synchronization pattern as the M series M1 to M4 which are the same as those at the time of recording. Are respectively sampled by the same binary number sequence as that at the time of recording, and the sampling results are integrated by the integrating circuits 85A to 85B, respectively. Thereby, the digital reproduction signal DX corresponds to the logical value of each bit b0 to b3 of the copyright protection information SA, and an integration result irrelevant to the logical value of the other bits b0 to b3 is obtained. Thus, the logical values of the bits b0 to b3 are decoded.
[0096]
Thereby, in the optical disk device 61, even when barcodes are recorded in an overlapping manner, a plurality of systems are further disturbed to generate a single drive signal so that different patterns are formed in adjacent tracks. Even when the copyright protection information SA is extremely difficult to find and duplicate, the copyright protection information SA can be reliably reproduced.
[0097]
By the way, if the copyright protection information SA to SC is recorded and the access to the mini disk 2 is controlled in this way, it is considered that illegal copying can be prevented and the copyright holder's profit can be surely protected. .
[0098]
However, for the mini-disc 2 created by unauthorized use of the cutting machine 7 itself, it is difficult to prevent distribution in the market because the copyright protection information SA to SC is correctly recorded.
[0099]
In this case, in this embodiment, it is possible to specify the manufacturing process related to the fraud by the copyright protection information SB by the pseudo random number R used for the disturbance of the copyright protection information SA.
[0100]
That is, in the optical disc inspection device 90 (FIG. 8), the copyright protection information SA is reproduced from the mini disc 2, and a modulation signal SXX is generated from the copyright protection information SA and the predicted value SBX of the copyright protection information SB. The signal SXX and the modulation signal SX detected from the mini disk 2 are compared. Here, the modulation signal SX obtained from the mini-disc 2 by the copyright protection information SC recorded in the form of a bar code is detected so as to be intermittently interrupted, but in one bit of the copyright protection information SB, a track is recorded. It is distributed over a relatively long distance in the direction and recorded together with the copyright protection information SA. Further, the copyright protection information SA is disturbed by the M series M1 to M4, and thus recorded on the minidisc 2. When the copyright protection information SB and the predicted value SBX set in this way match, many matching results can be obtained in the totaling result at a long distance in the track direction.
[0101]
As a result, in the optical disc inspection apparatus 90, the copyright protection information SB is sequentially switched and the matching results are tabulated, and the predicted value SBX having the largest matching ratio than the tabulation result is output as the copyright protection information SB.
[0102]
As a result, in this embodiment, it is possible to specify the illegal manufacturing based on the copyright protection information SB and implement the necessary counter means, thereby further protecting the interests of the copyright holder. it can.
[0103]
(3) Effects of the embodiment
According to the above configuration, a plurality of systems of signals generated by disturbing each bit string of the first information related to copyright are combined into one system based on a pseudo-random number corresponding to the second information related to copyright. By generating the drive signal, it is possible to protect the interests of the copyright holder more effectively than in the past.
[0104]
At this time, a synchronization pattern is inserted into the drive signal at a predetermined cycle, and at the time of reproduction, a binary number sequence is generated based on the synchronization pattern, and the information on the copyright recorded in this way is surely reproduced. can do.
[0105]
In addition, by repeatedly outputting a binary number sequence based on this synchronization pattern, for example, even when barcodes or the like are recorded and tracking control is difficult, information relating to copyright can be reliably reproduced. .
[0106]
Further, at the time of reproduction, decoding the second information about the copyright by comparing the light reception result obtained by the prediction of the first information about the copyright and the prediction of the second information about the copyright with the actual light reception result. Thus, it is possible to reliably reproduce the second information related to the copyright by the pseudo-random number used for the disturbance of the plurality of systems.
[0107]
(4) Other embodiments
In the above-described embodiment, the case of recording copyright protection information by 4-bit parallel has been described. However, the present invention is not limited to this and can be widely applied to cases of various numbers of bits.
[0108]
In the above-described embodiment, the case where the predicted value SBX of the second copyright information SB is sequentially switched to decode the second copyright information has been described. However, the present invention is not limited to this, and the copyright is not limited thereto. Instead of switching the predicted value SBX of the information SB, by a simultaneous parallel counting process using a plurality of random numbers R corresponding to the number of values that the copyright protection information SB can take, or a combination of counting and switching by a plurality of systems Thus, the second copyright protection information SB may be decrypted.
[0109]
In the above embodiment, the case where the barcode is overlapped and recorded has been described. However, the present invention is not limited to this and can be widely applied to the case where the recording of the copyright protection information by the barcode is omitted. it can. In addition, by adopting an error correction code or the like, the repeated recording of the copyright protection information SA may be omitted to reduce the area of the copyright information recording area. On the other hand, even if the recording of the copyright protection information SB using a barcode is omitted, it may be difficult to control tracking by intentionally creating a defect.
[0110]
In the above-described embodiment, the case where the copyright protection information SA, SB is recorded by the pit row has been described. However, the present invention is not limited to this, and can be widely applied to the case of recording by the mark row. it can.
[0111]
In the above-described embodiment, the case where the laser beam is directly modulated by the drive signal generated by the modulation circuit 27 has been described. However, the present invention is not limited to this, and the output signal of the modulation circuit 27 is further phase-modulated (phased). As the modulation, for example, the laser beam may be modulated by PE (Phase Encode), etc. In this way, the design of the reproduction side PLL circuit can be facilitated.
[0112]
In the above-described embodiment, the case where the synchronization patterns are arranged radially has been described. However, the present invention is not limited to this, and the synchronization patterns may be arranged at random positions in the radial direction.
[0113]
In the above-described embodiment, as the first and third information related to the copyright, the case of recording the key information that is unique to the mini-disc 2 and necessary for the encryption process has been described. The invention is not limited to this, and various information related to copyrights such as ID information unique to a mini-disc, information relating to a manufacturing factory, information controlling the date of manufacture or whether copying is permitted, etc. It can be widely applied to recording.
[0114]
Further, in the above-described embodiment, the case has been described in which input data is encrypted and recorded according to copyright information, and reproduction is performed after decryption. However, the present invention is not limited to this, and a reproduction-only optical disc is described. Can also be applied.
[0115]
Further, in the above-described embodiment, the case where encryption processing is performed based on copyright information has been described. However, the present invention is not limited to this, and can be widely applied to cases where access is stopped based on copyright information. it can.
[0116]
In the above-described embodiment, the case where the present invention is applied to a mini disk and related devices has been described. However, the present invention is not limited to this, and the present invention is not limited to this. Can be widely applied to various optical discs such as compact discs, digital video discs, phase change optical discs, and optical disc apparatuses for recording data by pit rows.
[0117]
In the above-described embodiment, the case where the pseudo-random number R is initialized in synchronization with the M sequence by the initialization pulse SY has been described. However, the present invention is not limited to this, and the initial value is based on a different standard from the initialization pulse. You may make it make it.
[0118]
【The invention's effect】
As described above, according to the present invention, a plurality of systems of signals generated by disturbing the respective bit strings of the first information related to copyright are set to 1 on the basis of pseudo-random numbers corresponding to the second information related to copyright. By generating the drive signal in a system, it is possible to protect the interests of the copyright holder more effectively than in the past.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a modulation circuit applied to a cutting machine according to an embodiment of the present invention.
FIG. 2 is a process diagram showing a manufacturing process of a minidisk according to an embodiment of the present invention.
FIG. 3 is a schematic diagram showing a mini-disc manufactured by the mini-disc manufacturing process of FIG. 2;
4 is a block diagram showing a cutting machine applied to the manufacturing process of FIG. 2; FIG.
FIG. 5 is a signal waveform diagram for explaining the operation of the modulation circuit of FIG. 1;
6 is a block diagram showing an optical disc apparatus for recording / reproducing the mini disc of FIG. 3; FIG.
7 is a block diagram showing a second decoding circuit of the optical disc apparatus of FIG. 6. FIG.
8 is a block diagram showing an optical disc inspection apparatus for inspecting the mini disc of FIG. 3. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Optical disc manufacturing process, 2 ... Mini disc, 3 ... Copyright information recording area, 7 ... Cutting machine, 8 ... Disc master, 27, 93 ... Modulation circuit, 41, 81 ... PLL circuit, 43 ...... Synchronization pattern generation circuit, 45A to 45D, 83A to 83D ....... M series generation circuit, 46A to 46D .... Calculation circuit, 47 .... Random number generation circuit, 29, 48, 49..Data selector, 61 .... Optical disk apparatus, 66, 94... Central processing unit, 68... Second decoding circuit, 82... Sync detection circuit, 84A to 84D... Multiply circuit, 85A to 85D.

Claims (16)

An optical disc apparatus for recording first and second information relating to copyright by irradiating a disc-shaped recording medium with a laser beam,
A sequence corresponding to the number of bits of the first information related to the copyright, which is uncorrelated with each other, and generates a binary sequence at a higher transmission rate than the transmission rate of the first information related to the copyright. A plurality of binary number sequence generating means;
A plurality of computing means for performing an exclusive OR operation with the corresponding bit of the first information on the copyright for the binary number sequence, and outputting a plurality of operation results;
Random number generating means for generating a pseudo-random number according to the second information relating to the copyright;
Selection means for outputting a drive signal by selective output of the plurality of calculation results in accordance with the pseudo-random number;
An optical disc device comprising: an optical modulation means for modulating the laser beam by the drive signal. The optical disc apparatus according to claim 1, wherein the binary number sequence is an M sequence. The optical disc apparatus according to claim 1, wherein a synchronization pattern is inserted in the drive signal at a predetermined period. 4. The optical disc apparatus according to claim 3, wherein the binary number sequence generation means repeatedly outputs the binary number sequence based on the synchronization pattern. The optical disk apparatus according to claim 1, wherein the operation by the operation means is an exclusive OR operation. The optical disk apparatus according to claim 1, wherein the light modulation unit modulates the laser beam with a phase modulation signal of the drive signal. In an optical disk recording method for recording first and second information relating to copyright by irradiating a disk-shaped recording medium with a laser beam,
Each bit string of the first information related to the copyright is subjected to an exclusive OR operation by a binary sequence which is faster than the transmission speed of the first information related to the copyright and is uncorrelated with each other. To generate multiple systems of signals,
Generating a pseudo-random number according to the second information relating to the copyright;
The plurality of systems of signals are selected by the pseudo random number to generate a system of drive signals,
An optical disk recording method for modulating the laser beam by the drive signal. An optical disc in which first and second information relating to copyright is recorded by a pit row or a mark row,
Each bit string of the first information related to the copyright has a higher transmission speed than the transmission speed of the first information related to the copyright, and each is an exclusive OR operation using binary sequences that are uncorrelated with each other. Then, the optical disc in which the pit row or mark row is created by a drive signal created in one system based on a pseudo-random number corresponding to the second information related to the copyright. Second information regarding the copyright is:
The optical disk according to claim 8, which is information for specifying manufacture of the optical disk. 9. The optical disc according to claim 8, wherein desired data is encrypted and recorded by the first information relating to the copyright. 9. The optical disc according to claim 8, wherein information related to the first and / or second information related to the copyright is recorded by recording a barcode that spreads radially. 12. The optical disc according to claim 11, wherein information related to the first and / or second information relating to the copyright is recorded in an area where the first and second information relating to the copyright are recorded. In an optical disc apparatus for reproducing second information relating to a copyright recorded on an optical disc,
Reproduction signal generating means for irradiating the optical disc with a laser beam to receive return light and generating a reproduction signal from the result of receiving the return light;
M-sequence binary sequence generating means for generating a binary sequence based on the synchronization pattern of the reproduction signal;
Computing means for performing an exclusive OR operation on the reproduction signal by the binary number sequence,
A plurality of integration means for integrating the calculation results of the calculation means and outputting a plurality of integration results in a 1-bit section of the copyright information;
Determining means for binary-identifying each of the integration results and decoding a corresponding bit string of the first information relating to the copyright;
Each bit string of the first information related to the copyright is converted to an exclusive OR by the binary sequence which is faster than the transmission speed of the first information related to the copyright and is uncorrelated with each other. A signal predicting means for generating a predicted reproduction signal in one system based on a predetermined pseudo-random number after calculation;
Based on a comparison result between the reproduced signal and the predicted reproduced signal, a logical value corresponding to the pseudo-random number is determined, and second information relating to the copyright is decoded based on the determination result. An optical disc apparatus comprising: 14. The optical disc apparatus according to claim 13, wherein the encryption of data recorded on the optical disc is released based on the first information related to the copyright. 14. The optical disc apparatus according to claim 13, wherein desired data is encrypted and recorded on the optical disc based on the first information relating to the copyright. In the reproducing method of the optical disc for reproducing the second information relating to the copyright recorded on the optical disc,
The optical disk is irradiated with a laser beam to receive return light, and a reproduction signal is generated from the result of receiving the return light,
Generating an M-sequence binary sequence based on the synchronization pattern of the reproduction signal;
An exclusive OR operation is performed on the reproduction signal by each binary number sequence,
In the 1-bit section of the copyright information, each of the exclusive OR calculation results is integrated to output a plurality of integration results,
Each of the integration results is binary-identified to decode a corresponding bit string of the first information regarding the copyright,
Each bit string of the first information related to the copyright is converted to an exclusive OR by the binary sequence which is faster than the transmission speed of the first information related to the copyright and is uncorrelated with each other. After the calculation, a predicted reproduction signal is generated in one system based on a predetermined pseudorandom number,
By determining a logical value corresponding to the pseudo-random number based on a comparison result between the reproduction signal and the predicted reproduction signal, an optical disc that decodes the second information related to the copyright based on the determination result Playback method.

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