JPH11126425A - Optical disk device, optical disk reproducing method and optical disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the analysis of encipherment difficult by obtaining a procedure, which is necessary for detecting from an optical disk a key information required for the release of encipherment, from outside an equipment other than the optical disk, and thereby changing the cryptographic method. SOLUTION: A digital signal processor, after generating a seek command to a servo circuit in response to a user's operation, binarizes with a prescribed threshold value the envelope detection result of a digital reproducing signal DRF obtained from the seek, and reproduces key information KY2. In addition, through a process corresponding to a data conversion circuit 9C at the time of recording, the key information KY2 is parallelly converted to form key information KY1, releasing the encipherment of a digital audio signal reproduced from a compact disk, in accordance with the processing program of a floppy disk supplied with the compact disk in pairs. Then, by the change of various processing procedures, the detection procedure of the key information KY2 is made changeable, as is data processing procedure or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an optical disk device,
The present invention relates to an optical disk reproducing method and an optical disk, for example, a compact disk, a reproducing apparatus and a reproducing method thereof. According to the present invention, illegal copying can be more reliably prevented as compared with the related art by acquiring a procedure necessary for detecting key information necessary for decryption from an optical disc from outside the device other than the optical disc. To do.

[0002]

2. Description of the Related Art Conventionally, in a compact disc,
Codes indicating the manufacturer, the manufacturing location, the disk number, and the like are engraved on the inner peripheral side of the lead-in area. By visually confirming this code, it is possible to identify the disk from other compact disks.

[0003]

By the way, the code of the manufacturer or the like recorded by the inscription is intended to be visually recognized. Therefore, there is a problem that illegal copying cannot be completely prevented.

As one method for solving such a problem, there is a method of recording identification data in a manner that makes it difficult to find identification data due to a change in pit width. However, even with this method,
Once the piracy trader knows the method of identifying the piracy, it may be imitated, and there is a problem that piracy cannot be completely prevented.

The present invention has been made in view of the above points, and is intended to propose an optical disk apparatus, an optical disk reproducing method, and an optical disk that can more reliably prevent illegal copying than in the past. is there.

[0006]

According to the present invention, there is provided an optical disk apparatus and a method for reproducing an optical disk, the method of generating key information from a second digital signal detected from an optical disk. Is obtained from outside the device other than the optical disk and set in the key information generating means.

Further, by applying the present invention to an optical disk device, a processing procedure for generating key information from a second digital signal detected from the optical disk can be changed by a device other than the optical disk.

[0008] A detection procedure for detecting a second digital signal required for generating key information from an optical disc by applying the method to an optical disc apparatus and a method for reproducing an optical disc is obtained from outside the device other than the optical disc, and a signal detecting means is provided. Set to.

Further, by applying the present invention to an optical disk apparatus, a detection processing procedure for detecting a second digital signal required for generating key information from an optical disk is set to be changeable by means other than the optical disk.

Further, the present invention is applied to an optical disk and records a first digital signal encrypted with predetermined key information and a second digital signal converted into the key information by a predetermined processing procedure. The processing procedure is transmitted by a predetermined information transmitting means.

When key information is generated from the second digital signal according to a predetermined processing procedure and the first digital signal is decrypted based on the key information, the second digital signal and the processing procedure are correctly associated with each other. Only when in
Can be correctly decrypted. On the premise of such a relationship, if this processing procedure is obtained from outside the device other than the optical disc and set in the key information generation means, this processing procedure can be changed as necessary. Thus, for example, the first digital signal is periodically encrypted, the second digital signal is changed, the processing procedure is changed to correspond to this change, and the processing procedure and the optical disk are analyzed and executed. Illegal copying can be prevented.

Further, this processing procedure can be set to be changeable by means other than the optical disk, and similarly, it is possible to cope with illegal copying.

[0013] Further, even if the detection procedure for detecting the second digital signal required for generating the key information from the optical disk is obtained from outside the device other than the optical disk and set in the signal detecting means, for example, the detection procedure may be performed periodically. The first digital signal can be encrypted, the second digital signal can be changed, and the detection procedure can be changed to correspond to this change, thereby preventing the detection procedure and illegal copying executed by analyzing the optical disk. .

Further, if the detection procedure for detecting the second digital signal required for generating the key information from the optical disk is set to be changeable, it is possible to deal with illegal copying in the same manner.

Further, the present invention is applied to an optical disc, and records a first digital signal encrypted by predetermined key information and a second digital signal converted into the key information by a predetermined processing procedure. If this processing procedure is transmitted by a predetermined information transmitting means, it is possible to deal with illegal copying in the same manner.

[0016]

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

FIG. 2 is a block diagram showing the mastering device. In this embodiment, the mastering device is selected as necessary, and the master disc 1 is sequentially exposed from the mastering device 1 to create a mother disc of a compact disc.

That is, in the mastering apparatus 1, the spindle motor 4 drives the master disk 2 to rotate at a predetermined rotation speed under the control of the spindle servo circuit 5. At this time, the spindle motor 4 outputs an FG signal FG whose signal level switches every time the master disc 2 rotates by a predetermined angle by the frequency generator mounted on the bottom.

The spindle servo circuit 5 controls the rotation speed of the spindle motor 4 with reference to the FG signal FG, so-called constant linear velocity (CLV).
Velocity), the rotation of the spindle motor 4 is controlled.

The recording laser 7 is composed of, for example, a gas laser, and emits a laser beam L1 to the optical modulator 8A. The optical modulator 8A and the optical modulator 8B are configured by, for example, an electroacoustic optical element. Among them, the optical modulator 8
A is the key information KY supplied from the key information generation circuit 9
2, the light amount of the laser beam L1 is changed. That is, when the logic level of the key information KY2 is logic 1, the laser beam L1 is emitted without attenuating, and when the logic level of the key information KY2 is logic 0, the laser beam L1 is emitted with attenuated by a predetermined light amount.

The light modulator 8B converts the laser beam L2 emitted from the light modulator 8A into EFM (Eight to Fourteen).
(Modulation) On / off control is performed in accordance with the signal S2 to perform injection.

The mirror 10 bends the optical path of the laser beam L3 emitted from the optical modulator 8B and emits it toward the master disk 2. The objective lens 11 condenses the light reflected by the mirror 10 on the recording surface of the master disc 2.
The mirror 10 and the objective lens 11 are sequentially moved in the radial direction in synchronization with the rotation of the disk master 2 by a thread mechanism (not shown). A track is formed spirally toward the side, and a pit shape corresponding to the EFM signal S2 is formed on the track.

Further, at this time, the light amount of the laser beam L1 is controlled by the optical modulator 8A, so that the key information K
Disc master 2 so that the pit width changes according to Y2
Is exposed, thereby changing the key information K by changing the pit width.
Record Y2.

Digital audio tape recorder 12
Outputs a digital audio signal D1 to be recorded on the master disc 2. Subcode generator 13
Generates a time code (consisting of hours, minutes, seconds, and frames) of the digital audio signal D1. Further, the subcode generator 13 generates and outputs subcode data SC to be recorded on the master disc 2 based on the time code. The subcode generator 13 also generates TOC data to be recorded in the lead-in area, and outputs the data at a corresponding timing.

The key information generation circuit 9 determines the key information KY1 and KY based on the time code of the subcode data SC.
Generate 2. That is, the key information generation circuit 9 inputs the subcode data SC to the address decoder 9A, and decodes the time code here. The memory IC 9B is a read-only memory that holds bit information or an EP-RO
M, DES with time code as address
It outputs 54-bit key information KY1 using (Data Encryption Standard) code. As a result, the key information generation circuit 9 generates the key information KY corresponding to the time code for each frame as a processing unit of the digital audio signal D1.
Outputs 1.

The data conversion circuit 9C converts the 54-bit key information KY1 into second key information KY2 and outputs the same. Here, in the data conversion circuit 9C, the content of the data conversion process is set according to the specification of the compact disk created by the mastering device 1. For example, by converting the key information KY1 into serial data, and according to the specification, The second key information KY2 is generated by changing the arrangement and modulating. In this embodiment, the data conversion circuit 9C simply converts the key information KY1 into serial data and outputs it.

The encryption circuit 15 has a first key information KY1.
Thus, the digital audio signal D1 is encrypted and output.

The modulation circuit 16 processes the audio data output from the encryption circuit 15 in accordance with the format prescribed for the compact disc, thereby generating an EFM signal S2. That is, the modulation circuit 1
6 forms a frame structure by dividing audio data in frame units and sequentially allocating subcode data SC supplied from the subcode generator 13. Further, after adding an error correction code to each frame, an interleaving process is performed, and further EFM modulation is performed.
A signal S2 is generated.

In the manufacturing process of the compact disk according to this embodiment, a mother disk is prepared by developing the disk master 2 and further performing an electroforming process.
A stamper is created using this mother disk. Further, a disk-shaped substrate is formed by injection molding using the stamper, and a reflective film and a protective film are sequentially formed on the disk-shaped substrate to form a compact disk.

Thus, in the compact disk created by using the mastering apparatus 1, an encrypted digital audio signal D1 is recorded by repeating a pit sequence, and is generated from the encrypted key information KY1 by a predetermined processing procedure. The recorded key information KY2 is recorded by a change in the pit width.

FIG. 3 is a block diagram showing a compact disc player for playing the compact disc created in this way. In the compact disk player 20, the spindle motor 21 drives the compact disk 23 to rotate under the condition of a constant linear velocity under the control of the servo circuit 22.

The optical pickup 24 generates, from the return light obtained by irradiating the compact disk 23 with a laser beam, a reproduction signal RF whose signal level changes in accordance with the amount of the return light. Further, the optical pickup 24
Under the control of the servo circuit 22, the compact disc 23
In the radial direction, thereby enabling a desired track to be sought.

The binarizing circuit 25 converts the reproduced signal RF into a binary signal.
After the binarized signal is generated by the binarization, a reproduction clock is generated from the binarized signal. Further, the binarization circuit 25 reproduces the reproduction data BD from the reproduction signal RF by sequentially latching the binarization signal based on the reproduction clock.

The EFM demodulation circuit 26 outputs the reproduced data B
D is EFM demodulated and output. The ECC circuit 27
After deinterleaving the output data of the M demodulation circuit 26, the output data is subjected to error correction processing using an error correction code added to the output data, and is output.

The encryption processing circuit 28 receives the output data of the ECC circuit 27 and receives a digital signal processor (D)
SP) The encryption is decrypted by the key information KY1 outputted from the SP) 30 and outputted.

Digital-to-analog conversion circuit (D / A) 2
9 performs digital-to-analog conversion processing on the output data of the encryption processing circuit 28, thereby outputting an audio signal SA based on an analog signal.

For such an audio data reproducing system, the analog-to-digital converter (A / D) 31
The reproduction signal RF is subjected to analog-to-digital conversion processing with reference to the reproduction clock CK, thereby generating and outputting a digital reproduction signal DRF.

The digital signal processor 30 includes:
By executing the processing procedure shown in FIG. 4, when the reproduction of the compact disk 23 is started, the processing procedure supplied by the floppy disk 33 is loaded. Further, the digital signal processor 30 generates key information KY1 according to the processing procedure, and sets the key information KY1 in the encryption processing circuit 28.

Here, this processing procedure is based on a detection procedure for detecting the second key information KY2 recorded according to the change in the pit width, and a data processing procedure for generating key information KY1 from the second key information KY2. Be composed.

In this detection procedure, the digital signal processor 30 detects the change in the pit width by detecting the signal level of the reproduced signal RF from the digital reproduced signal DRF. Further, the servo circuit 22 is controlled in accordance with the processing procedure supplied by the floppy disk 33, so that a change in the pit width can be detected from a desired track of the compact disk 23.

In the data processing procedure, the digital signal processor 30 can process a digital signal detected by a change in pit width by processing corresponding to the data conversion circuit 9C of the mastering device 1.

The digital signal processor 30 includes:
In the processing procedure shown in FIG. 4, the process proceeds from step SP1 to step SP2, and a program consisting of the processing procedure is loaded from the floppy disk 33. Subsequently, the digital signal processor 30 proceeds to step SP3, acquires key information KY2 from the compact disk 23 according to the detection procedure included in this processing procedure, and further obtains the key information KY2 from the key information KY2 according to the data processing procedure included in this processing procedure. The information KY1 is generated. In the following step SP4, the digital signal processor 30 sets the key information KY1 in the encryption processing circuit 28, and then proceeds to step SP5 to end this processing procedure.

In this embodiment, the digital signal processor 30 executes the processing procedure of step SP3 and step SP4 of this series of processing in accordance with the loaded program in units of frames of reproduced data obtained from the compact disc 23. The key information KY1 is generated by the processing corresponding to the recording.

That is, the digital signal processor 30 issues a seek command to the servo circuit 22 in response to a user operation, and then envelope-detects the digital reproduction signal DRF obtained from the seek. Further, the result of the envelope detection is binarized by a predetermined threshold value, thereby reproducing the key information KY2. The key information KY2 is further subjected to parallel conversion processing by processing corresponding to the data conversion circuit 9C during recording, thereby generating key information KY1.

Thus, in the compact disk player 20, the digital audio signal reproduced from the compact disk 23 is decrypted in accordance with the processing program for the floppy disk 33 supplied with the compact disk 23. By changing the processing procedure supplied from 33, the detection procedure of the key information KY2 and the data processing procedure for generating the key information KY1 from the key information KY2 can be changed by various processing procedures.

FIG. 1 is a schematic diagram showing the relationship between the mastering device 1 and the compact disc player 20.
The compact disc manufacturing side 40 determines the key information KY1 to be generated based on the recording position of the key information KY2, the relationship with the time code, and the like within a range that satisfies the condition that the compact disc player 20 can reproduce the key information. Thus, the specifications of the compact disc 23 are determined.

The computer 41 generates key information KY1 to be recorded in the memory IC 9B described above with reference to FIG.
On the compact disk manufacturing side 40, the key information K
Y1 is recorded in the memory IC 9B and supplied to the disk factory 42. In addition, the information that records the data conversion processing of the data conversion circuit 9C is supplied to the disk factory 42 together with the tape cassette 43 that records the digital audio signal.

The disk factory 42 selects the mastering device 1 according to the specifications of the compact disk. Further, the memory IC 9B is set in the mastering device 1, and the data conversion process of the data conversion circuit 9C is set. Under these conditions, the digital audio signal recorded on the tape cassette 43 is recorded on the master disk 2. Further, a compact disc 23 is created from the master disc 2.

Further, the computer 41 uses a compact disk player to detect key information KY2 and to detect key information KY2 from the reproduced key information KY2.
1 is recorded on the floppy disk 44 according to the data processing procedure for creating the data No. 1.

On the compact disk manufacturing side 40, the contents of the floppy disk 44 are copied in the copying device 45 to create the floppy disk 33 described above with reference to FIG. 3, and the combination of the compact disk 23 and the floppy disk 33 is combined. Supplied to the user.

In the above configuration, when the specification of the compact disk 23 is determined on the compact disk manufacturing side 40 (FIG. 1), the computer 4 is operated in accordance with the determination.
1, key information KY1 for encrypting the digital audio signal is created, and this key information KY1 is stored in the memory IC.
9B and supplied to the disc factory 42. The data conversion method for generating the key information KY2 to be recorded on the compact disk 23 from the key information KY1 is notified to the disk factory 42.

In response to this, in the disk factory 42, the mastering device 1 is selected for producing this compact disk (FIG. 2), and the memory IC 9B is set in the key information generation circuit 9 of the mastering device 1, and the data conversion circuit 9C data conversion processing is set to the notified data conversion method.

Thus, in the mastering device 1, the memory IC 9B is accessed by the time code of each frame of the digital audio signal D1.
The digital audio signal D1 is encrypted by the key information KY1 stored in 9B. Further, subcode data SC and an error correction code are added to the digital audio signal D1, and EFM modulation is performed to generate an EFM signal S2. In the mastering device 1, the rotating disk master 2 is irradiated with the laser beam L3, and the laser beam L3 is controlled to be turned on and off by the EFM signal S2, so that the pit shapes corresponding to the EFM signal S2 are sequentially exposed on the disk master 2. You.

In parallel with this processing, the mastering device 1
Then, in the data conversion circuit 9C, the computer 41
Key information KY1 by the data conversion process notified by
Is converted into key information KY2, and the light amount of the laser beam L1 is switched according to the key information KY2. In the manufacturing factory of the compact disc (FIG. 1), a compact disc 23 is created from the disc master 2 thus exposed, and the key information KY2 is recorded by a change in the pit width.

In the compact disk 23 manufactured in such a manner that the pit width is changed, in the copying method in which the protective film and the reflection film are peeled off and the stamper is manufactured from the disk-shaped substrate, the pit width is changed. Damage, which makes piracy difficult. Further, when a copy compact disc is created by using an EFM signal or the like obtained by reproducing the compact disc, the pit width change is lost, thereby preventing illegal copying by this type of method.

On the other hand, on the other hand, the compact disc manufacturing side 40 prepares the key information KY2 recorded on the compact disc 23.
Key information KY from the key information KY2
1 is a data processing procedure for the floppy disk 33.
The floppy disk 33 is copied and provided to the user in combination with the compact disk 23.

Thus, with respect to a regular compact disk distributed through a regular distribution route, the digital audio signal obtained from the compact disk can be correctly decrypted by combining the corresponding floppy disk 33. On the other hand, for an illegally copied compact disc created by analyzing the encryption of the compact disc, data conversion for periodically generating the key information KY2 from the recording position of the key information KY2 and the key information KY1 is performed. By changing the method, the key information KY1 itself, and the like, analysis can be made substantially difficult. Also, even if an encryption method based on these relationships is analyzed and an illegal copy is created, by changing these relationships, etc., the correspondence relationship with the processing procedure provided by the floppy disk 33 is incorrect. This makes it difficult to correctly reproduce the encrypted digital audio signal.

That is, on the user side (FIG. 3),
The compact disc 23 provided in this combination
Then, the floppy disk 33 is set in the compact disk player 20, and at the start of reproduction, the processing procedure recorded on the floppy disk 33 is loaded into the digital signal processor 30. In the compact disk player 20, the reproduction signal RF is converted into a digital reproduction signal DRF by the analog-to-digital conversion circuit 31 in accordance with the detection procedure of the loaded processing procedure, and the envelope of the digital reproduction signal DRF is detected by the digital signal processor 30. Key information KY
2 is detected.

According to the data processing procedure included in the loaded processing procedure, the key information KY2 is converted into key information KY1 composed of parallel data, and the key information KY1 is sequentially set in the encryption processing circuit 28. As a result, in the compact disk player 20, the data processing sequence obtained by reproducing the compact disk 23 is decrypted in the encryption processing circuit 28, and the resulting digital audio signal is converted into an analog signal and output. .

According to the above configuration, when reproducing the digital audio signal recorded by encryption, the key information KY2 recorded by the pit width is detected according to the detection procedure provided from the floppy disk 33, and Key information K in accordance with the data processing procedure provided
By converting Y2 into key information KY1 and decrypting it, and by setting this detection procedure and data processing procedure to be changeable by the floppy disk 33 which is an external device other than the optical disk, encryption is performed as necessary. The detection procedure and the data processing procedure can be changed so as to correspond to this. This makes it difficult to create an illegal copy by analyzing the encryption process by changing the encryption as necessary, and also to make it difficult to correctly reproduce even if it is illegally copied. In comparison, illegal copying can be more reliably prevented.

Further, by detecting the second key information KY2 recorded based on the pit width, it is possible to make the key information KY2 recorded based on the pit width difficult to copy for a compact disk illegally copied. This can also eliminate piracy.

In the above-described embodiment, the key information KY1 is sequentially stored in correspondence with the sequentially changing subcode data.
Has been described, but the present invention is not limited to this, and can be widely applied to a case where encryption is performed using specific key information KY1. In this case, in the mastering device 1 described above with reference to FIG.
This can be handled by outputting key information KY1 having a fixed value from 9B. Further, the key information KY2 can be recorded only at a specific address of the compact disc 23. In this case, dummy information is provided in other places, and further, the key information KY1 and KY2 are used as references for detection and data conversion. Department information can also be recorded. Further, in the compact disk player 20, at the time of starting the reproduction, the specific address is reproduced according to the processing procedure supplied from the floppy disk 33, and the key information KY2 is detected. Note that these are in relation to the above embodiment in that the procedure for detecting the second digital signal recorded based on the pit width is changed.

In the above-described embodiment, the key information KY1 is simply converted into parallel data to convert the key information KY1 into parallel data.
However, the present invention is not limited to this, and the present invention is not limited to this. The conversion method can be widely applied. In this case, the mastering device 1 described above with reference to FIG. 2 can cope with this by changing the data conversion process of the data conversion circuit 9C. In the compact disk player 20, the detected key information KY2 can be processed by data processing in accordance with the data processing procedure supplied from the floppy disk 33. Note that these are in relation to the above embodiment in that the data processing procedure for generating key information from the second digital signal is changed.

Further, in the above-described embodiment, the case where the second digital signal composed of the key information KY2 is recorded by changing the pit width has been described. However, the present invention is not limited to this. When forming and recording the second digital signal, the present invention can be widely applied to the case where the second digital signal is recorded by displacement of the pit length. In this case, the compact disk player can cope with any of these methods, and the second digital signal recorded by any of these methods according to the detection procedure provided from the floppy disk 33, or a combination thereof. The recorded second digital signal will be detected.

In the above-described embodiment, a case has been described where the processing procedure is provided by a floppy disk as an external device other than the compact disk. However, the present invention is not limited to this, and a memory chip such as a flash memory may be used. A processing procedure may be provided, and further, a communication line such as a telephone line may be provided.

Further, in the above-described embodiment, the case where the present invention is applied to a compact disk has been described. However, the present invention is not limited to this and can be widely applied to various optical disks such as DVDs and optical disk reproducing apparatuses. it can.

[0067]

As described above, according to the present invention, a procedure necessary for detecting key information necessary for decryption from an optical disk is obtained from outside the device other than the optical disk, thereby making it necessary. The encryption method can be changed accordingly to make the encryption analysis difficult, and even if an illegal copy is created by the encryption analysis, correct reproduction can be made difficult. This makes it possible to more reliably prevent illegal copying as compared with the related art.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a manufacturing process and the like of a compact disk according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a mastering device applied to the process of FIG.

FIG. 3 is a block diagram showing a compact disc player used for reproducing a compact disc created by the mastering device of FIG. 2;

FIG. 4 is a flowchart showing a processing procedure of a digital signal processor in the compact disc player of FIG. 3;

[Explanation of symbols]

1 Mastering device 2 Master disk 9
Key information generation circuit, 9A ... address decoder, 9B ...
... Memory IC, 9C ... Data conversion circuit, 20 ... Compact disk player, 23 ... Compact disk, 31 ... Analog / digital conversion circuit, 30 ... Digital signal processor, 33, 44 ... Floppy disk

Claims (13)

[Claims] 1. An optical disk device for irradiating an optical disk with a laser beam to reproduce the optical disk, a reproduction signal generating means for generating a reproduction signal whose signal level changes in accordance with return light of the laser beam, First reproduction signal processing means for performing binary identification of the first digital signal to reproduce the first digital signal; encryption processing means for decrypting the first digital signal using predetermined key information; The second key required to generate the key information
Signal detection means for detecting the digital signal of the above, key information generation means for generating the key information from the second digital signal by a predetermined processing procedure, and obtaining the processing procedure from outside the device other than the optical disk And an input means for setting the key information generating means. 2. The optical disk, wherein the second digital signal is recorded according to the width of a pit or a mark, and the signal detecting means detects a signal level of the reproduced signal and outputs a signal level detection result. 2. The optical disk device according to claim 1, further comprising: a detection unit; and an identification unit that reproduces the second digital signal based on a result of the signal level detection. 3. The optical disk device according to claim 1, wherein said input means acquires said processing procedure from a predetermined recording medium different from said optical disk. 4. The optical disk device according to claim 1, wherein said input means acquires said processing procedure via a predetermined transmission path. 5. An optical disk device for irradiating an optical disk with a laser beam to reproduce the optical disk, wherein: a reproduction signal generating means for generating a reproduction signal whose signal level changes in accordance with a return light of the laser beam; First reproduction signal processing means for performing binary identification of the first digital signal to reproduce the first digital signal; encryption processing means for decrypting the first digital signal using predetermined key information; The second key required to generate the key information
Signal detection means for detecting a digital signal of the following, and key information generation means for generating the key information from the second digital signal by a predetermined processing procedure, wherein the key information generation means, An optical disk device characterized by being set to be changeable by means other than an optical disk. 6. An optical disk apparatus for irradiating an optical disk with a laser beam to reproduce the optical disk, wherein: a reproduction signal generating means for generating a reproduction signal whose signal level changes in accordance with a return light of the laser beam; First reproduction signal processing means for performing binary identification of the first digital signal to reproduce the first digital signal; encryption processing means for decrypting the first digital signal using predetermined key information; Signal detection means for detecting, from the optical disc, a second digital signal required for generating the key information; key information generation means for generating the key information from the second digital signal; Input means for acquiring from outside the device other than the optical disc and setting the signal detection means. . 7. The optical disk, wherein the second digital signal is recorded according to the width of a pit or a mark, and the signal detecting means detects a signal level of the reproduced signal from a position designated by the detecting procedure. 7. The optical disk apparatus according to claim 6, further comprising: signal level detecting means for outputting a signal level detection result by using the signal level detecting means; and identification means for reproducing the second digital signal based on the signal level detection result. . 8. The optical disk device according to claim 6, wherein said input means acquires said detection procedure from a predetermined recording medium different from said optical disk. 9. The optical disk device according to claim 6, wherein said input means acquires said detection procedure via a predetermined transmission path. 10. An optical disk apparatus for irradiating an optical disk with a laser beam to reproduce the optical disk, wherein: a reproduction signal generating means for generating a reproduction signal whose signal level changes in accordance with a return light of the laser beam; First reproduction signal processing means for performing binary identification of the first digital signal to reproduce the first digital signal; encryption processing means for decrypting the first digital signal using predetermined key information; A signal detecting unit for detecting a second digital signal necessary for generating the key information from the optical disk; and a key information generating unit for generating the key information from the second digital signal. An optical disc apparatus, wherein the detecting means is set so that the detection procedure can be changed by means other than the optical disc. 11. A first digital signal is reproduced by binary-identifying return light obtained by irradiating a laser beam onto an optical disk, and a key is obtained from a second digital signal detected from the optical disk by a predetermined processing procedure. An optical disc reproducing method for generating information and decrypting the first digital signal with the key information, wherein the processing procedure is obtained from outside the device other than the optical disc. How to play. 12. A first digital signal is reproduced by binary-identifying return light obtained by irradiating a laser beam on an optical disk, and a second digital signal is detected from the optical disk by a predetermined detection procedure. A method for reproducing an optical disc, wherein key information is generated from a second digital signal, and the first digital signal is decrypted using the key information, wherein the detection procedure is obtained from outside the device other than the optical disc. A method for reproducing an optical disk, comprising: 13. The first encrypted with key information.
An optical disc characterized by recording a digital signal and a second digital signal converted into the key information by a predetermined processing procedure, and transmitting the processing procedure by predetermined information transmitting means.