JP4120093B2 - Information digital recording method and apparatus using disk-shaped optical recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a recording method for a disk-shaped optical recording medium in which the recorded disk-shaped optical recording medium is copied one after another, and the so-called “grandchild copy” is copied as meaningless at all.
[0002]
[Prior art]
Recently, an apparatus for recording and reproducing information such as voice, music, and video in a digital format is rapidly spreading. When recording and playing back information in digital format, there is a feature that there is no deterioration in sound quality and image quality no matter how many times the copy is repeated, but on the other hand, problems such as infringement of the rights of copyright holders due to unauthorized copying have emerged. Yes.
The present invention provides a method in which a commonly recorded “grandchild copy” is copied with no sense at all by copying one after another with the recorded medium as a parent, resulting in prevention of unauthorized copying.
[0003]
As a first method for controlling copying in a system that records information in digital form, SCMS (Serial Copy Management System) is used for music information, and CGMS (Copy Generation Management System) is used for video information. It has been adopted.
[0004]
Each of these is a method that defines a flag for generation management, and performs control such as copying freedom, copying prohibition, and copying permission only once depending on the state of the generation management flag, and can be realized with a simple circuit configuration. It has the following features.
As a second method, the input information is not recorded as it is, but once it is encrypted and recorded, it can be copied, but it cannot be restored to the original information without the key used for encryption. It is a method.
[0005]
FIG. 3 and FIG. 4 show a block configuration of a method for performing copy control using a generation management flag, which is the first conventional method.
In FIG. 3, the signal read from the copy source medium 31 is subjected to processing such as error correction in the decoder block 32, and then the information recorded on the medium is sent to the output terminal. From the decoder block 32, a generation management flag signal is supplied to the generation management determination block 33, and the generation management state relating to the information recorded on the medium 31 is determined.
[0006]
Here, if the result determined in the generation management determination block 33 indicates that copying is prohibited, a mechanism may be considered in which the decoder block 32 does not send information to the output terminal 34 in order to prevent unauthorized copying.
However, if this is done, for example, there is a problem that nothing is reproduced when the information recorded on the medium is not reproduced but simply connected to an amplifier or television with digital input to reproduce the information.
Therefore, the generation output flag is merely added to the digital output terminal 34 to the information recorded on the recording medium 31.
[0007]
FIG. 4 shows a block diagram when the input information is recorded on the medium in digital form.
In the block configuration diagram when recording on the medium shown in FIG. 4, for example, the information and the generation management flag described above are integrally supplied to the input terminal 41, and the information is subjected to predetermined processing in the encoder block. And recorded on a recordable recording medium 44.
[0008]
On the other hand, the generation management flag detection determination block 43 detects the generation management flag added to the input information, determines the state indicated by the flag, and controls the encoder block 42 in accordance with the state.
[0009]
For example,
1) If copying is indicated, recording on the medium 44 is permitted without changing the current flag.
2) If only one-time copying is permitted, the generation management flag is rewritten to a copy-prohibited state, and then recording on the recording medium 44 is permitted.
3) If copy prohibition is indicated, the encoder block 42 is controlled to stop recording on the medium 44.
The above is the outline of the management method for copying information that has been adopted.
[0010]
Naturally, for example, by ignoring the input generation management flag in the generation management flag detection determination block 43 shown in FIG. 4, or by rewriting the generation management flag from the signal supplied to the input terminal 41. Unauthorized copying can be easily done. In particular, a recording / reproducing apparatus for a personal computer, which has recently become widespread rapidly, has a problem that there is almost no mechanism for detecting such a flag, so that it can be easily copied.
[0011]
Next, a second method for preventing unauthorized copying will be briefly described with reference to FIG.
Information from the input terminal 51 is encrypted by the encryption block 52 and then recorded on the writable recording medium 54 via the encoder block 53.
[0012]
A block 55 is an encryption key generation block for generating a key for encryption. One of several predetermined key bundles is selected, or an encryption key is generated by generating a random number. .
Then, the key information is sent to the encryption block 52 and recorded on the recording medium 54 for decryption.
At this time, the key information is usually recorded in a special area so that it is not normally output to the outside.
[0013]
If the information is recorded after being encrypted in this way, even if it is copied, if the encryption is not broken, it becomes meaningless at all, and as a result, illegal copying is prevented.
However, since the key information is recorded in the recording medium 54 even though it is a special area, if the entire recording medium including the area where the encryption key information is recorded is copied, the encryption can be broken. Is included.
[0014]
[Problems to be solved by the invention]
Naturally, for example, in the generation management flag detection determination block 43 shown in FIG. 4, the generation management flag of the input is ignored or the generation management flag is rewritten from the signal supplied to the input terminal 41. Unauthorized copying can be easily done.
[0015]
In particular, a recording / reproducing apparatus for a personal computer, which has recently become widespread rapidly, has a problem that such a flag can be easily copied because there is almost no mechanism for detecting such a flag.
Further, as shown in FIG. 5, even though the key information is a special area, it is recorded on the disc-shaped optical recording medium 54. Therefore, the entire medium including the area where the key information is recorded is copied. For example, it includes a problem that the encryption is broken.
[0016]
[Means for Solving the Problems]
In order to solve this problem, claim 1 of the present invention provides a digital information recording method using a disc-shaped optical recording medium having a read-only area and a writable area, and at least on the disc-shaped optical recording medium. The input information is encrypted by encrypting the input information using the positional relationship between the position information of the signal recorded in the magnetic recording area provided in one place and the position information of the reference point signal in the read-only area as encryption key information. Is recorded in the writable area, and a method for digitally recording information using a disk-shaped optical recording medium is provided. Claim 2 of the present invention provides a disk-shaped optical recording having a writable area. In the digital recording method of information using a medium, position information of a signal recorded in at least one magnetic recording area provided on the disk-shaped recording medium and the writable area The disc-shaped light is characterized in that the input information is encrypted using the positional relationship with the position information of the read signal from the reference position as encryption key information, and the encrypted input information is recorded in the writable area. A method for digitally recording information using a recording medium is provided. Claim 3 of the present invention is the method for digitally recording information using the disk-shaped optical recording medium according to claim 1 or 2, wherein the disk Provided is a method for digitally recording information using a disk-shaped optical recording medium, characterized in that information for generating an encryption key is written in the magnetic recording area provided on the optical disk-shaped recording medium. According to claim 4, in the digital recording apparatus for information on a disc-shaped recording medium using a disc-shaped optical recording medium having a read-only area and a writable area, at least on the disc-shaped optical recording medium. A magnetic signal detector for detecting position information of a signal recorded in a magnetic recording area provided in one place, a reference point detector for detecting position information of a reference point signal in the read-only area, and the disc-shaped optical recording An encryption key generator for generating encryption key information from a positional relationship between position information of a signal recorded in a magnetic recording area provided in at least one location on the medium and position information of a reference point signal in the read-only area; An encryption unit that is supplied with an output signal of an encryption key generation unit and encrypts input information, and an encoder unit that encodes the output signal of the encryption unit and generates a signal to be recorded in the writable area. An information digital recording apparatus using a disc-shaped optical recording medium is provided. Claim 5 of the present invention provides digital information recording using a disc-shaped optical recording medium having a writable area. In the recording apparatus, a magnetic signal detector for detecting position information of a signal recorded in a magnetic recording area provided in at least one place on the disk-shaped optical recording medium, and a read signal from a reference position in the writable area A reference point detector for detecting the position information of the signal, position information of the signal recorded in the magnetic recording area provided at least at one place on the disc-shaped optical recording medium, and a read signal from the reference position in the writable area an encryption key generating unit for generating the encryption key information from the positional relationship between the position information of an encryption unit to which an output signal of the encryption key generating unit encrypts the input information is supplied, the output signal of the encryption unit And a digital recording device for information using a disc-shaped optical recording medium, characterized in that it comprises an encoder section for generating a signal to be recorded in the writable area. According to a sixth aspect of the present invention, in the information digital recording apparatus using the disk-shaped optical recording medium according to the fourth or fifth aspect, the magnetic recording area provided on the disk-shaped optical recording medium. Provides a digital information recording apparatus using a disk-shaped optical recording medium, in which information for generating an encryption key is written.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, the key management method used when the information is recorded after being encrypted without being recorded as it is is greatly different from the conventional one.
[0018]
In order to understand the basic concept of encryption key management according to the present invention, it will be described with reference to FIG. As shown in FIG. 1A, reference numeral 14 denotes a writable disc-shaped optical recording medium. A part of the inner circumference is provided with a read-only area 14A, and a writable area 14B is provided on the outer circumference. The read-only area may be on the outer periphery.
[0019]
A specific place or reference point in the read-only area 14A is indicated by 14a in the figure. The reference point 14a is a specific place determined from a read-only signal, and is not particularly directly visible from the outside.
[0020]
On the other hand, 14 m in the figure is a magnetic recording area provided on the surface of the disc-shaped optical recording medium 14.
In the present invention, key information for encryption is generated from the positional relationship between the reference point 14a and the magnetic recording area 14m, and the input information is encrypted using this key information.
[0021]
By the way, since the magnetic recording area 14m is provided on the surface of the disk-shaped recording medium 14 by printing, the positional relationship with the reference point 14a differs for each medium, and conversely, when such a disk-shaped recording medium is mass-produced. It is impossible to keep the positional relationship between the reference point 14a and the magnetic recording area 14m constant.
[0022]
As a result, this means that the encryption key information differs from medium to medium. Even if the encrypted information is copied to another medium as it is, the key information will be different. Can not be solved.
The above is the basic method of key management according to the present invention.
[0023]
An embodiment of a digital information recording method and apparatus using a disk-shaped optical recording medium incorporating a key management method according to the present invention will be described below with reference to FIG.
FIG. 2 shows an embodiment of a digital recording apparatus incorporating the key management method according to the present invention. The disk-shaped optical recording medium 14, the encryption block 22 to which input information is supplied, and the recording on the disk-shaped optical recording medium 14. The encoder block 23, the encryption key generation block 25, the reference point detection block 26, the magnetic signal detection block 27, and the phase difference detection unit 28 that generate signals.
The reference point detection block 26 is a reference point detection block for detecting the position information of the reference point 14a described above from the read-only area 14A of the disc-shaped optical recording medium 14 by the pickup 14ap.
[0024]
The magnetic signal detection block 27 is a magnetic signal detection block that reads position information from the magnetic recording area 14m printed on the surface of the disk-shaped optical recording medium 14 by a pickup 14mp.
Since the rotation speed of the reference point and the rotation speed of the printed magnetic recording medium are the same, the mutual positional relationship (phase difference) can be determined from the detection results of the two blocks 26 and 27.
From the positional information on the reference point 14a and the positional information on the magnetic recording area 14m, the phase difference detection block 28 can determine the mutual positional relationship (phase difference).
[0025]
In the encryption key generation block 25, the output of the phase difference detection block 28 is supplied, and an encryption key is generated using the positional relationship value and supplied to the encryption block 22.
As a matter of course, since the key generation for the encryption is necessary before the input information is written to the disc-shaped optical recording medium 14, it is necessary to generate the encryption key prior to the information writing operation. .
[0026]
An encryption key can also be generated in the same procedure when information recorded after encryption is read out and returned to the original information.
The above is the outline of the operation of the apparatus employing the key management method according to the present invention.
[0027]
Another embodiment of the information digital recording method and recording apparatus using the disc-shaped optical recording medium of the present invention will be described below with reference to FIG.
In FIG. 1A so far, the reference point is within the read-only area of the disc-shaped optical recording medium 14, but as shown in FIG. 1B, it is within the writable area 14B. However, the reference point 14c can be provided.
Generally, read-only information, for example, address information is often recorded in advance on the writable recording medium 14, and therefore a specific address can be used as the reference point 14c.
[0028]
Alternatively, even if it is information written by itself instead of read-only information, for example, if it is information that always exists at a fixed position, such as a volume descriptor of a file system, this can be used as the reference point 14c. .
On the other hand, 14m is a magnetic recording area provided on the surface of the disc-shaped optical recording medium 14, and the setting method is the same as in FIG.
In the present invention, key information for encryption is generated from the positional relationship between the reference point 14c and the magnetic recording area 14m, and the input information is encrypted using this key information.
[0029]
By the way, since the magnetic recording area 14m is provided on the surface of the disk-shaped optical recording medium 14 by printing, for example, the positional relationship with the reference point 14c differs for each medium, and conversely such a disk-shaped recording medium is mass-produced. In this case, it becomes impossible to keep the positional relationship between the reference point 14c and the magnetic recording area 14m constant.
[0030]
As a result, this means that the encryption key information differs from medium to medium. Even if the encrypted information is copied to another medium as it is, the key information will be different. Can not be solved.
[0031]
Next, the magnetic recording area 14m formed on the surface of the disk-shaped optical recording medium 14 by, for example, printing will be described.
The signal to be recorded here can be a simple signal necessary to determine the position. However, if a certain amount of information is recorded and used together with the positional relationship information for generating the encryption key, the key safety is ensured. The sex can be improved that much.
[0032]
【The invention's effect】
As described above, the encryption key information for encryption is generated based on the positional relationship between the magnetic recording area on the surface of the disk-shaped optical recording medium and the signal read from the reference position in the disk-shaped optical recording medium. Therefore, simply copying the information in the disc-shaped optical recording medium cannot decrypt the code, and as a result, it helps prevent unauthorized copying.
[0033]
Furthermore, providing a magnetic recording area on a disk-shaped optical recording medium can be easily realized by a printing method or the like, and has a feature that it is suitable for mass production.
[Brief description of the drawings]
FIG. 1 shows a basic conceptual diagram of a digital recording method of information using a disc-shaped optical recording medium according to the present invention and an illegal copy prevention system of the apparatus.
FIG. 2 is a block diagram showing an embodiment of a digital information recording method and apparatus using a disc-shaped optical recording medium incorporating illegal copy prevention according to the present invention.
FIG. 3 shows an example of a configuration of a reproducing side in a recording / reproducing apparatus using a conventional generation management flag.
FIG. 4 shows a configuration example of a recording side in a recording / reproducing apparatus using a conventional generation management flag.
FIG. 5 shows an example of the configuration of a recording apparatus that encrypts information for the purpose of preventing unauthorized copying.
[Explanation of symbols]
14 disc-shaped optical recording medium 14A read-only area 14B writable area 14a, 14c reference point 14ap, 14mp pickup 14rh recording head 14m magnetic recording area 22 encryption unit (encryption block)
23 Encoder unit (encoder block)
25 Encryption key generator (encryption key generation block)
26 Reference point detector (reference point detection block)
27 Magnetic signal detector (magnetic signal detection block)
28 Phase difference detector (phase difference detection block)

Claims (6)

In a digital recording method of information using a disc-shaped optical recording medium having a read-only area and a writable area,
The input information is encrypted by using the positional relationship between the position information of the signal recorded in the magnetic recording area provided at least at one place on the disk-shaped optical recording medium and the position information of the reference point signal in the read-only area as encryption key information. And recording the encrypted input information in the writable area, the method of digitally recording information using a disc-shaped optical recording medium In a digital recording method of information using a disc-shaped optical recording medium having a writable area,
The positional relationship between the positional information of the signal recorded in the magnetic recording area provided in at least one place on the disk-shaped optical recording medium and the positional information of the read signal from the reference position in the writable area is used as encryption key information. A method for digitally recording information using a disc-shaped optical recording medium, wherein the input information is encrypted, and the encrypted input information is recorded in the writable area. In the digital recording method of the information using the disk shaped optical recording medium of Claim 1 or Claim 2,
An information digital recording method using a disk-shaped optical recording medium, wherein information for generating an encryption key is written in the magnetic recording area provided on the disk-shaped optical recording medium. In a digital recording apparatus for information on a disk-shaped recording medium using a disk-shaped optical recording medium having a read-only area and a writable area,
A magnetic signal detector for detecting position information of a signal recorded in a magnetic recording area provided in at least one place on the disc-shaped optical recording medium;
A reference point detector for detecting position information of a reference point signal in the read-only area;
An encryption key for generating encryption key information from a positional relationship between position information of a signal recorded in a magnetic recording area provided in at least one place on the disk-shaped optical recording medium and position information of a reference point signal in the read-only area A generator,
An encryption unit that is supplied with an output signal of the encryption key generation unit and encrypts input information;
An information digital recording apparatus using a disc-shaped optical recording medium, comprising: an encoder section that encodes an output signal of the encryption section and generates a signal to be recorded in the writable area. In a digital recording apparatus for information using a disc-shaped optical recording medium having a writable area,
A magnetic signal detector for detecting position information of a signal recorded in a magnetic recording area provided in at least one place on the disc-shaped optical recording medium;
A reference point detector for detecting position information of a read signal from a reference position in the writable region;
The encryption key information from the positional relationship between the position information of the read signal from the reference position of the disc-shaped optical recording magnetic recording position information and the writable area of the recording signal to the region provided at at least one location on the medium An encryption key generation unit to generate,
An encryption unit that is supplied with an output signal of the encryption key generation unit and encrypts input information;
An information digital recording apparatus using a disk-shaped optical recording medium, comprising: an encoder unit that encodes an output signal of the encryption unit and generates a signal to be recorded in the writable area. In the digital recording apparatus of the information using the disk shaped optical recording medium of Claim 4 or Claim 5,
An information digital recording apparatus using a disk-shaped optical recording medium, wherein information for generating an encryption key is written in the magnetic recording area provided on the disk-shaped optical recording medium.

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