JP2001307426A - Data management methods - Google Patents

Abstract

(57) [Problem] To provide a data management method capable of protecting copyright when a multimedia program is recorded on an information storage medium and distributed. SOLUTION: A multimedia program 101, a title key 108, copyright information 1 are stored in an information storage medium 110.
Record 09. However, the title key 108 and the copyright information 109 are recorded in a protected area on the information storage medium 110, and are protected so that only a legitimate device according to the copyright protection method can read and update the information. Prevent reproduction and duplication.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information storage medium, such as a memory card or an optical disk, which stores a multimedia program composed of a plurality of digitized multimedia data such as video, audio, still image, text, and scene description. The present invention relates to a copyright protection method for preventing unauthorized copying and viewing by a person who does not have the right to use the multimedia program when stored.

[0002]

2. Description of the Related Art In recent years, devices for digitizing and recording multimedia data such as video, audio and still images have become widespread, and such multimedia data is stored in information storage media such as memory cards and optical disks. If the digital data is to be distributed for a fee, it is necessary to take measures to prevent unauthorized viewing and duplication by those who do not have the right to use the digital data, since the digital data has the property of being easily copied without deterioration.

On the other hand, various data management methods for encrypting multimedia data with an encryption key that can be known only to those who have the right to use it and storing the data in an information storage medium have been proposed in the past.

[0004]

In these methods, the entire information storage medium or an individual file storing multimedia data is used as a copyright information management unit.
On the other hand, a multimedia work can only be used to the fullest extent if it is created by combining multiple media.There are few situations in which a multimedia work is composed of a set of multiple multimedia data including scene description information. Absent. Therefore,
It is necessary to manage the copyright information efficiently and effectively, which has a high affinity with the “multimedia program” composed of a plurality of multimedia data as described above.

[0005]

Therefore, according to the present invention, copyright information is managed in units of multimedia programs.
By encrypting each file storing multimedia data constituting one multimedia program with an encryption key called a title key common to the multimedia program, the copyright of the creator of the multimedia program is protected. Protect.

In addition, the title key is stored together with copyright information in a protected area provided on an information storage medium storing the multimedia program, and the protected area can be read. Only the unauthorized device can decrypt and play / use the multimedia program by using the title key, thereby preventing duplication, playback, and falsification of the copyright information of the multimedia program by an unauthorized device. .

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS.

(First Embodiment) FIG. 1 is a conceptual diagram showing an example of a multimedia program composed of a plurality of multimedia data and a copyright information management method proposed in the present invention.

FIG. 2 shows a mechanism for recording a multimedia program according to the first embodiment of the present invention. In FIG. 2, reference numeral 10 denotes a storage device, and reference numeral 11 denotes multimedia data constituting the multimedia program. A multimedia program generating unit, 12 is a multimedia program generating unit, 13 is an encryption determining unit that determines whether or not each multimedia data is encrypted, 14 is a multimedia data encryption module using a secret key cryptosystem, Reference numeral 15 denotes a title key generation unit that allocates a title key to the multimedia program, 16 denotes a copyright information generation unit that generates copyright information of the multimedia program, 20 denotes an information storage medium that stores the multimedia program, and 24 denotes information. A user who is a readable and writable storage area of the storage medium 20 Frequency, 25 information protected area protection is a storage region of the storage medium 20, 17 and 21 are each storage device 10 and the information storage medium 20, input-output unit to the user area 24, 19 and 23 are protected area 25
Input and output units 18 and 22 are mutual authentication units for the recording device 10 and the information storage medium 20.

One or a plurality of multimedia data S11 produced by the multimedia data producing means 11 is inputted to a multimedia program producing section 12, and
The multimedia program S12 synthesized and generated by the above is input to the encryption determination unit 13. At this time, the identification information S13 relating to the multimedia program generated by the multimedia program generation unit is the copyright information generation unit 16
Then, the copyright information S18 and the title key S17 are output to the multimedia program S12 by the copyright information generation unit 16 and the title key generation unit 15, respectively.

The multimedia data S14 determined to be encrypted by the encryption determining unit 13 is input to the encryption module 14, and is encrypted by the secret key encryption method using the title key S17. Input to the input / output unit 17. On the other hand, the unencrypted multimedia data S15 is directly input to the user area input / output unit 17. User area input / output unit 17
Inputs the encrypted multimedia data and multimedia data S20 to the user area input / output unit 21 of the information storage medium 20 that is the recording destination, and the user area input / output unit 21 directly converts the encrypted multimedia data and multimedia data S24. It is recorded in the user area 24.

Copyright information S18 and title key S17
Is input to the protected area input / output section 23 of the information storage medium 20, and the protected area input / output section 23 directly receives the copyright information and the title key S25. Is recorded in the protected area 25. However, the protection area input / output sections 19 and 23 are previously set to the mutual authentication sections 18 and 2
2 establishes authentication as a valid device or information storage medium according to the copyright protection method by exchanging authentication information S21, and operates only when input / output permission is given by control signals S19 and S24. Can be. This makes it possible to prevent creation of an unauthorized copy of the multimedia program using an unauthorized information storage medium that does not protect the title key.

If a public key encryption method is adopted as a multimedia data encryption method and the title key S17 is a public key, even if the reproducing device 10 is a legitimate device according to the copyright protection method, It is also possible to prohibit a person other than a specific viewer who knows the corresponding secret key from playing the multimedia program by the playback device 10. In this case, it is necessary for the playback device to provide a mechanism in which the viewer inputs a secret key and uses the secret key for decryption instead of the title key.

(Embodiment 2) FIG. 3 shows a mechanism for reproducing a multimedia program according to Embodiment 2 of the present invention. Reference numeral 20 denotes an information storage medium on which the multimedia program is recorded in Embodiment 1. , 30 is a multimedia program reproducing device, 31 is a user area input / output section, 32 is a mutual authentication section, 33 is a protected area input / output section, and 34 is whether or not the read multimedia data is encrypted. A decryption determination unit, 35 is a decryption module, 36 is a copyright information processing unit, and 37 is a multimedia program playback unit.

The multimedia program recorded on the information storage medium 20 is composed of one or more sets of multimedia data, and each multimedia data is stored in a separate file. In reproducing the multimedia program, first, the information storage medium 20
The user area input / output unit 21 reads a set S30 of multimedia data and encrypted multimedia data that is multimedia data encrypted for copyright protection from a file recorded in the user area 24,
A set S32 of multimedia data and encrypted multimedia data is input to the user area input / output unit 31 of the playback device 30.
Enter

Next, the user area input / output unit 31 inputs the set S36 of the multimedia data or the encrypted multimedia data to the decryption determination unit 34, and the decryption determination unit 34
Inputs the encrypted multimedia data S39 of S36 to the decryption module 35, and outputs the multimedia data S39.
40 is input to the multimedia program reproducing unit 37. At this time, the decryption determination unit can determine whether or not each multimedia data is encrypted by the extension of the name of the file in which the multimedia data is stored.

On the other hand, the mutual authentication unit 22 of the information storage medium 20
When the mutual authentication is successfully performed by exchanging the mutual authentication information S34 between the remote authentication unit 32 and the mutual authentication unit 32 of the playback device 30, control signals S23 and S35 are output, and the information storage medium 20 and the protected area input / output unit 23 of the playback device 30 are output. And 33 become operable, and subsequently, the protected area input / output unit 23
Reads the title key and copyright information S31 corresponding to the multimedia program to be reproduced from the protected area 25, and inputs the title key and copyright information S33 to the protected area input / output unit 33 of the reproducing apparatus 30. The protection area input / output unit 33 inputs the copyright information S37 to the copyright information processing unit 36 and the title key S38 to the decryption module 35.

Finally, the decryption module 35 uses the title key S38 to encrypt the multimedia data S39.
And the decoded multimedia data S41
Is input to the multimedia program reproducing unit 37. According to the control information S42 from the copyright information processing unit 36, the multimedia program reproducing unit 37 reproduces sets S40 and S41 of multimedia data constituting the multimedia program.

At this time, if the copyright information is configured so that the control information S42 input from the copyright information processing unit 36 indicates the limitation of the playback time, the limitation of the portion that can be played, etc. Settings can be made.

(Embodiment 3) FIG. 4 shows a mechanism of moving and duplicating a multimedia program according to Embodiment 3 of the present invention. Reference numeral 20 denotes information obtained by recording the multimedia program in Embodiment 1. A storage medium, 40 is a transfer / copy device for transferring and copying multimedia programs, and 48 is an information storage medium to which the multimedia programs are transferred and copied. The multimedia program recorded on the information storage medium 20 is transferred to another information storage medium 4
The case of moving to and copying to No. 8 will be described below.

The multimedia data constituting the multimedia program recorded in the user area 24 of the information storage medium 20 is encrypted for those requiring copyright protection. A copy may be generated in the user area 52 of the storage medium 48. This is performed according to the following procedure. The user area input / output unit 21 of the information storage medium 20 reads a set S30 of multimedia data and encrypted multimedia data constituting the multimedia program from the file recorded in the user area 24, , A set S32 of multimedia data and encrypted multimedia data is input. The user area input / output unit 47 of the moving / copying apparatus 40 receives a set S5 of multimedia data and encrypted multimedia data from the user area input / output unit 41.
8, the set S59 of the multimedia data and the encrypted multimedia data is input to the user area input / output unit 49 of the information storage medium 48 at the transfer / copy destination. The user area input / output unit 49 records the set S63 of the multimedia data and the encrypted multimedia data in the user area 52.

Next, when the mutual authentication succeeds in the exchange of the mutual authentication information S50 between the mutual authentication section 22 of the information storage medium 20 and the mutual authentication section 42 of the moving / copying apparatus 40, control signals S23 and S51 are output. Then, the protected area input / output sections 23 and 43 of the information storage medium 20 and the moving / copying apparatus 40 become operable. The information S31 is read from the protection area 25, and the title key and the copyright information S3 are input to the protection area input / output unit 43 of the moving / copying apparatus 40.
Enter 3.

Subsequently, the copyright information S53 is input from the protected area input / output unit 43 to the copyright information processing unit 44.
The copyright information S53 includes whether or not the movement of the corresponding multimedia program is permitted, or the number of copies that can be generated. Based on this, the copyright information processing unit 44 moves and copies the corresponding multimedia program. Determine whether it is possible.

When the transfer / copying is possible, the mutual authentication information S60 is exchanged between the mutual authentication unit 46 of the transfer / copy apparatus 40 and the mutual authentication unit 50 of the transfer / copy destination information storage medium 48 to exchange the information. After the authentication, the protected area input / output units 45 and 51 become operable by the control signals S57 and S62. The protected area input / output unit 43 inputs the title key S52 to the protected area input / output unit 45.

Further, the copyright information processing section 44 writes, based on the original copyright information S53, copyright information S56 describing whether the moved, copied multimedia program is further moved, whether or not copying is permitted, and the like. Is generated and input to the protected area input / output unit 45. Subsequently, the protected area input / output section 45 inputs the title key and the copyright information S61 to the protected area input / output section 51 of the information storage medium 48, and the protected area input / output section 51 inputs the title key and the copyright information S61.
64 is recorded in the protected area 53.

If the operation is movement, after recording the title key and the copyright information S64 in the protection area 53 of the information storage medium 48, a flag indicating that the copyright information processing section 44 has been moved is set. The copyright information S54 updated by addition or the like is input to the protection area input / output unit 43, and the protection area input / output unit 43 inputs the copyright information S55 to the protection area input / output unit 23 of the information storage medium 20, and then Copyright information S
65 is written back to the protected area 25 and the information storage medium 20
Process so that the above multimedia program cannot be played. The moved multimedia program on the information storage medium 20 can be prevented from being reproduced by deleting the title key of the moved multimedia program from the protected area 25 of the information storage medium 20 of the transfer source.

If the operation is copy, after recording the title key and copyright information S64 in the protection area 53 of the information storage medium 48, the copyright information S54 in which the number of copies that can be generated is updated is updated. By writing back to the protected area 25 of the information storage medium 20 in the same manner as in the case of the above-described moving operation, the number of generated copies is managed.

[0028]

As described above, according to the present invention, the copyright of a multimedia program composed of a plurality of multimedia data recorded and distributed on an information storage medium is efficiently and safely protected. be able to.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an example of a multimedia program composed of a plurality of multimedia data and a copyright information management method proposed in the present invention.

FIG. 2 is a block diagram illustrating an example of a recording operation of a multimedia program according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing an example of a playback operation of a multimedia program according to Embodiment 2 of the present invention;

FIG. 4 is a block diagram showing an example of a moving and copying operation of a multimedia program according to Embodiment 3 of the present invention;

[Explanation of symbols]

Reference Signs List 10 Multimedia program recording device 11 Multimedia data generating means 12 Multimedia program generating unit 13 Encryption determining unit 14 Encryption module 15 Title key generating unit 16 Copyright information generating unit 17, 31, 41, 47 User on device side Area input / output unit 18, 32, 42, 46 Mutual authentication unit on device side 19, 33, 43, 45 Protected area input / output unit on device side 20, 48, 110 Information storage medium 21, 49 User area on information storage medium side Input / output unit 22, 50 Mutual authentication unit on information storage medium 23, 51 Protected area on information storage medium Input / output unit 24, 52 User area on information storage medium 25, 53 Protected area on information storage medium 30 Multimedia Program playback device 34 Decoding determination unit 35 Decoding module 36, 44 Copyright information processing unit 37 Multimedia program reproducing unit 40 Multimedia program moving / copying device 101 Multimedia program 102 Video data 103 Text data 104 Still image data 105 Music / audio data 106 Scene description information 107 Multimedia works to be reproduced 107 108 Title key of multimedia program 101 109 Copyright information of multimedia program 101

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Claims (6)

[Claims] 1. Multimedia data including video, music / audio, still image, text, etc., and scene description information describing a temporal / spatial relationship between the data. What is claimed is: 1. A data management method for multimedia data stored in an information storage medium, wherein one title key (encryption key) is assigned to one multimedia program, and each multimedia data constituting the multimedia program is allocated to the multimedia program. A data management method characterized by preventing unauthorized duplication and reproduction of the multimedia program by encrypting the multimedia program using the common title key. 2. The data management method according to claim 1, wherein a secret key cryptosystem is used for the encryption processing. 3. The information storage medium includes a protected area protected from access to other than a legitimate device according to the copyright protection method, in addition to an area for storing the multimedia data. 2. The method of claim 1, wherein a title key and copyright information corresponding to the multimedia program are stored in the protected area to prevent unauthorized alteration and duplication of the title key and copyright information.
Data management method described in. 4. The data management method according to claim 1, wherein the multimedia data is stored in a plurality of files. 5. The data management method according to claim 4, wherein a copyright holder can select whether or not to encrypt the multimedia data for each stored file. 6. The data management method according to claim 4, wherein whether or not the multimedia data is encrypted is determined by an extension of a name of a stored file.