JP2008278509A - Data use device, data application method and its program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data use device enabling evaluations to be properly received while content is being protected, enabling content users to use only when they want to use in the amount they want to use it, and enabling advertising providers certainly to have users use advertisements. <P>SOLUTION: A data use device comprises: an encryption-key extraction means for extracting an encryption key from watermarked second data; a data decryption means for decrypting encrypted first data into first data using the encryption key extracted by the encryption-key extraction means; an authentication means for verifying whether or not predetermined conditions for using the first data are met; a data output means for causing to be executed, based on user instructions and on results of verification by the authentication means, decryption of the first data by the encryption-key extraction means and the data decryption means, and for reproducing the decrypted first data as output or otherwise reproducing the second data as output; and a time-administration-information recording means for recording, as a use history, time-administration-information based on a use time or use counts for each of the data contained in digital contents to be distributed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention protects the rights of digital contents including moving images to prevent unauthorized use, and uses the data distribution method for linking the distributed digital contents and commercial advertising information and the like based on predetermined conditions. The present invention relates to a data use apparatus, a data use method, and a program for using the possible digital content.

In recent years, infrastructure development using keywords such as broadband and digital broadcasting has been progressing rapidly, and in particular, development of optical fiber networks for broadband access networks in urban areas is progressing. Such subscriber-based optical fiber network development is expected to progress more rapidly according to the government goals of the e-Japan strategy.
In a user environment where the Internet line is always connected, users can subdivide content usage units from packages into images by deciding whether to use each content while evaluating the content. There is sex. This provides the user with an opportunity to evaluate the content and provides a usage environment that takes into account the content selection rights.

  In Internet distribution, time-consuming content such as moving images and streaming images can be linked with CM providers such as advertisements as well as terrestrial and digital broadcasting. This is because the content usage status can be monitored and managed on-time, and therefore, a time selling business for the CM provider becomes possible by linking with the CM provider. In this case, there is a possibility that the content can be provided to the user at a low fee due to the advertising expense from the CM provider.

  However, since the conventional content management technology for moving images and streaming images is based on the use in units of packages, the license check for usage restrictions is usually performed once before use, and the content of the user is the content. It is difficult to restrict usage while evaluating Therefore, since there is no environment in which users can properly evaluate the content of the content, it does not stimulate the willingness to purchase or activate the content market, which is one of the factors that hinder content creators (indie labels, etc.) It is connected.

In addition, the video content distribution business has a problem that it is difficult to establish a business model for advertising, etc., compared to terrestrial broadcasting. This is thought to be due to the fact that at present, there is no provision of a mechanism that can link content used on the Internet with CM providers.
In the present invention, the content can be legitimately evaluated in a protected state, the content user can use as much as he wants, and the CM provider ensures that the user uses the advertisement. A data utilization apparatus, a data utilization method, and a program thereof are provided.

  The data utilization apparatus according to the present invention uses digital content including encrypted first data obtained by encrypting first data with a predetermined encryption key and watermarked second data in which the encryption key is embedded as an invisible digital watermark. A data utilization device for extracting the encryption key from the watermarked second data, and the first data encrypted by using the encryption key extracted by the encryption key extraction means A data decrypting means for decrypting the data, an authenticating means for authenticating whether or not a predetermined condition for using the first data is satisfied, an encryption key extracting means based on an instruction from the user and an authentication result by the authenticating means And data output means for executing decoding of the first data by the data decoding means and reproducing and outputting the decoded first data, or reproducing and outputting the second data; And a time management information recording means for recording time management information based on the usage time or usage count for each data included in the digital content that is the fabric as the utilization history.

Here, it is possible to further comprise time management information output means for outputting the usage history recorded by the time management information recording means for billing management.
Further, the time management information recording means can be configured to extract the time management information for each data embedded as an invisible digital watermark in the second data and record it as a usage history.
Further, the time management information can be compared with reference information related to the usage status possessed by each data, and further provided with a tamper detection means for verifying the presence or absence of tampering.

  The data utilization method according to the present invention uses digital content including encrypted first data obtained by encrypting first data with a predetermined encryption key and watermarked second data in which the encryption key is embedded as an invisible digital watermark. A data utilization method executed in a data utilization apparatus for performing the process, the step of extracting an encryption key from the watermarked second data, and the encrypted first data using the encryption key extracted by the encryption key extraction means Of the first data, based on the instruction from the user and the authentication result by the authentication means, the step of authenticating whether or not a predetermined condition for using the first data is satisfied, Executing the decryption and reproducing and outputting the decrypted first data or reproducing and outputting the second data; and for each data included in the distributed digital content And a step of recording the time management information based on the use time or the usage number as the usage history.

  The program according to the present invention uses digital content including encrypted first data obtained by encrypting first data with a predetermined encryption key and watermarked second data in which the encryption key is embedded as an invisible digital watermark. A data utilization method program executed in the data utilization apparatus of the first embodiment, wherein the encryption key is extracted from the watermarked second data, and the encrypted first data using the encryption key extracted by the encryption key extraction means Of the first data, based on the instruction from the user and the authentication result by the authentication means, the step of authenticating whether or not the predetermined condition for using the first data is satisfied, Performing decryption and reproducing and outputting the decrypted first data or reproducing and outputting the second data; and a distributed digital container Is a program for executing the data utilization method and a step of recording the time management information based on the usage time or the usage count for each data included in the tool as the usage history to the computer.

  In the present invention, the encryption key when the first data such as the pay image is encrypted is embedded as an invisible digital watermark in the second data that can be used unconditionally such as advertisement information, and the security of the first data is increased. It can be maintained at a high level, and the right of digital data can be protected by preventing falsification of information. In addition, it is possible to legitimately obtain the evaluation of the data content by the content user, and it is possible to improve the convenience of the content provider during distribution. In addition, the content user can obtain as much information as he wants and can reduce the billing amount to the minimum necessary. When advertising information is used as the second data, the billing amount is further suppressed, and the convenience for the content user is further improved.

[Overview configuration]
In the present invention, assuming a network content business that “uses the scene you want to see at the moment, only the time you want to see and pays for the time you see”, the following two elemental technologies are required to realize this: I think.
(1) On-time, real-time content usage control technology based on content usage rights
(2) Billing technology linked to CM usage
As an element of (1), we propose a method of switching between two types of images (encrypted, plaintext) in real time using external information. For (2), we propose a method of accurately counting the CM usage and charging based on the count information.

FIG. 1 shows a usage model (business model) of a system that employs an embodiment of the data usage apparatus of the present invention. Here, the model assumes a CM provider 10, a content provider 20, a content user 30, and an operation monitor 40.
The CM provider 10 provides the content provider 20 with an advertisement (CM) including moving image data and a CM usage fee.

The content provider 20 obtains user information including image usage range information from the content user 30 and then provides the content and usage software to the content user 30.
Further, the content provider 20 provides operation management information including usage right information generated from the image usage range information to the operation monitor 40, and operation management such as time codes included in each data in the content. Based on the report, the usage status of the content user 30 (CM, usage time of paid image) is grasped. Further, the content provider 20 manages the usage time of CMs and pay images based on operation management reports such as time codes and usage right information, and performs billing processing.

The operation supervisor 40 manages the usage status of the user based on a usage history such as a time code included in each data in the content.
The content user 30 makes a usage request to the operation supervisor 40 and uses data in the range specified by the referenced usage right information. If no usage range is specified, CM usage is assumed.
By adopting such a configuration, the following can be realized.
(1) CM usage information (usage time, usage count, etc.) can be managed, and usage information storage, statistics, and other services that use usage information can be realized.
(2) The use management by time code makes it possible to realize a discount service for paid images according to the amount of CM usage.

〔data structure〕
An example of the data structure used in the data utilization apparatus of the present invention is shown in FIG. A data group included in the distributed digital content is composed of a plurality of image data 100. Each image data 100 includes a real image part 110 and a data extension part 120.
The real image stored in the real image unit 110 is stored in a general-purpose AV data format in which only a part of a CM image or a pay image made up of advertisement information is made visible. Data extension information stored in the data extension unit 120 includes an encrypted image part 121 and a data reproduction information part 122. The encrypted image portion 121 stores an encrypted image for restoring a pay image, and the data reproduction information portion 122 stores restoration information including image type information of the pay image.

FIG. 3 shows a process for reproducing a CM image or a pay image.
In image reproduction, output data (CM image or pay image) is generated based on input data (protected image) and usage right information input from the outside. Based on usage rights information including information unique to each image such as a time code and usage permission information, either a CM image or a pay image is selected as an output processing target for each image.

  As shown in FIG. 3, the input data is separated for each image into a real image stored in the real image unit 110 and data expansion information stored in the data expansion unit 120. The stored data extension information is separated into an encrypted image stored in the encrypted image unit 121 and data reproduction information stored in the data reproduction information unit 122. The real image stored in each real image unit 110 has an encryption key embedded with an invisible digital watermark. The encryption key is extracted from the real image, and the encrypted image stored in the cipher image unit 121 is stored. Decrypt.

Then, based on the usage right information, a CM image stored in the real image unit 110 or a decrypted pay image is generated and output. At this time, based on the data reproduction information (image type), a data conversion process such as image synthesis of the actual image and the image separated and decoded from the data extension unit is executed.
Among data reproduction information, for example, type 1 shown in FIG. 5, type 2 shown in FIG.

Type 1 shown in FIG. 5 is a model in which only the CM image 210 stored in the real image portion 110 is used and the pay image 220 is not shown. In this case, the pay image 220 is stored in the encrypted image unit 121 as encrypted data encrypted with the encryption key.
Type 2 shown in FIG. 6 is a model in which a CM window 240 is created in the pay image 230 and both a part of the pay image and the CM image are used unconditionally. In this case, only the portion of the pay image 230 located in the CM window 240 is stored in the encrypted image unit 121 as the encrypted data 250.

Both Type 1 and Type 2 integrate two types of images (real image part: plaintext, encrypted image part: encryption), and store type 1 and type 2 selection information as image types in data reproduction information To do.
In both types 1 and 2, when the content of the usage right information is “unusable”, only the real image part is used. When the content of the usage right is “usable”, in type 1, the encrypted data stored in the encrypted image unit 121 is decrypted and used, and reproduced and output. In type 2, the encrypted data 250 stored in the encrypted image unit 121 is decrypted and then combined with the CM window 240 of the actual image unit 230 and used.

As described above, the distributed digital content is composed of a plurality of images including the CM portion image and the pay image made up of advertisement information, and depending on the contents of the usage right information, as shown in FIG. When you switch dynamically between images and paid images and do not have usage rights, only CM images are allowed to be used.
[Content use]
Consider using the digital content distributed with the data structure as described above to realize enhanced security for paid images and real-time image restoration at the same time.

The following two functions are proposed as security enhancement methods.
(1) Each image is encrypted with an encryption key that has a one-to-one correspondence with each image data (for each frame).
(2) The content usage management corresponding to the time code is executed.
<Encrypt each image with a one-to-one encryption key>
By encrypting a part or all of the pay image with a different encryption key for each image, the prevention of unauthorized use of the pay image is strengthened.

Specifically, among the CM images, an encryption key (for example, 8 bytes) obtained by encrypting the first frame of the pay image is embedded in the first CM image as an invisible digital watermark. For the encryption key obtained by encrypting the subsequent frame of the pay image, encryption key related information obtained by the logical operation with the leading encryption key is generated and stored in the header portion of the corresponding CM image.
As shown in FIG. 7, when the image is used, the encryption key K [1] is extracted from the head CM image (first frame 301). For subsequent frames (second frame 302, third frame 303...), The encryption key related information stored in the header portion of the CM image is extracted, and this and the encryption key K [1] extracted from the first frame. Are generated, encryption keys K [2], K [3],... For decrypting each frame of the subsequent pay image are generated.

  In general, the watermark embedding amount depends on the number of frames and the image bit rate, and real-time watermark extraction processing is often difficult. Therefore, the encryption key is watermarked and embedded only in the first CM image, and a logical operation is performed on the encryption key related information extracted from the header part and the encryption key extracted from the first CM image to generate an encryption key for the subsequent pay image. Thus, the time required for the encryption key extraction process can be shortened and the moving image reproduction process can be performed smoothly.

By this method, it is possible to reproduce an image in real time while eliminating the limitation on the amount of information such as an encryption key and increasing the security strength.
<Content usage management corresponding to time code>
As one of means for managing the content usage state of the content user 30 and measuring the content usage amount, pay-as-you-go billing by time code can be considered. The time code is stamped on each image when the image data is generated. The issues here are time code falsification prevention and accurate content usage management. FIG. 8 shows a method for solving the above problems and capable of enhancing security.

By embedding management information corresponding to the time code in the image, the time code can be prevented from being falsified. Generally, the time code is stored in a header, and data can be tampered with. Therefore, the management information associated with the time code is embedded in the CM image as an invisible digital watermark, and the time code is checked for tampering by checking the time code against the management information at the time of accounting.
In addition, a usage check is performed with the time code related information and the usage right, the usage time is monitored when the CM image is used, and billing processing is performed with reference to the CM usage information when the pay image is used. For example, for a pay-per-use charge that occurs depending on the usage time or the number of times of use of a pay image, a charge is determined by performing a discount according to the usage time or the number of times of use of the CM image.

By the above method, it is possible to perform a safe and reliable billing process for each image. The management information and time code are sequentially provided as a usage history from the content user 30 to the operation supervisor 40 regardless of the CM image and the pay image when reproducing the content.
〔Demonstration experiment〕
A demonstration experiment was conducted to verify the effectiveness of the content protection method that links such CM images. An image usage library that can be used with Windows Media Player (registered trademark) provided by Microsoft has been created. This library is one type of filter that can be executed in the Direct Show environment, and can use AVI format Motion JPEG. In this library, image data with audio can be used.

Fig. 9 shows the experimental system.
Here, a configuration is shown in which a content production PC on which content generation software is installed for content generation and a content use PC on which a usage tool and this library are installed are connected to each other for the purpose of content usage.
The content production PC generates content usage right information and stores it in a storage means as a sharable file (usage right).

In the content use PC, when the content use tool selects the protected content, the library acquires the usage right information stored in the storage means of the content production PC and executes the use of the content.
This test object is a protected image with audio data, and it is confirmed that paid images and advertisement images (CMs) can be reproduced normally without problems such as missing images. Table 1 shows the experimental environment.

上記実験環境にて、有料画像あるいはCM画像の再生実験し、音声と画像を正常に利用できることを確認できた。また、図１０の画像再生例の如く、利用権情報の内容(利用可/利用不可)を変化させた場合でも、画像再生が可能であることを確認できた。

In the above experimental environment, it was confirmed that sound and images can be used normally by experimenting with pay images or CM images. Further, it was confirmed that the image reproduction was possible even when the content of the usage right information (usable / unusable) was changed as in the image reproduction example of FIG.

  The present invention proposes a method of switching between two types of images (encrypted and plaintext) in real time according to external information, with the goal of realizing real-time content usage control on time. Here, we devised a content data structure that can protect the rights, and realized a means to encrypt each image with a one-to-one encryption key. In addition, we proposed a fee-based image charging method according to the usage amount of CM, and devised a content usage management means corresponding to the time code. As a result, paid images can be used while strengthening security.

As a result of prototyping this method and measuring the performance of two image types, both of the two image types are within the practical range for Motion JPEG images with a frame rate of about 30 and a bit rate of about 500 Kbps. I was able to confirm that. It was also demonstrated that dynamic screen switching control is feasible.
[Other Embodiments]
A) In addition to the real image part and the data extension part, a second data extension part may be further provided so that information such as an encryption key is stored as metadata in the second extension part. In this case, it is not necessary to embed an encryption key as an invisible digital watermark in the CM image stored in the real image portion.

FIG. 11 shows an example in which the type 1 data shown in FIG. 5 is in such a data format.
Here, the CM image 210 stored in the real image portion is left as it is, and the pay image 221 is encrypted with a predetermined encryption key and stored in the encrypted image portion of the data extension portion. Also, information related to the encryption key, encryption logic version information, authentication information, and the like are stored in the second data extension unit 260 as description data (metadata).

FIG. 12 shows an example in which the type 2 data shown in FIG. 6 is in such a data format.
Here, the model is a model in which a commercial image window 240 is created in the pay image 230 and both a part of the pay image and the commercial image are used unconditionally. Is stored as encrypted data 251 in the encrypted image portion of the data extension portion. Also, information related to the encryption key, encryption logic version information, authentication information, and the like are stored in the second data extension unit 270 as description data (metadata).

In both types 1 and 2, the real image part, the data extension part, and the second data extension part are integrated, and selection information of type 1 and type 2 is stored in the data reproduction information as an image type.
In both types 1 and 2, when the content of the usage right information is “unusable”, only the real image portion is used. When the content of the usage right is “usable”, in type 1, the encrypted data stored in the encrypted image unit 121 is decrypted and used, and reproduced and output. In Type 2, the encrypted data 251 stored in the encrypted image unit 121 is decrypted and then combined with the CM window 240 of the actual image unit 230 and used.

As for the distributed data, the contents of the second data expansion units 260 and 270 are read using a predetermined application, and are used by the content user based on the contents.
B) In the above-described embodiment, the permission information for the digital content playback process is managed as the usage right information, and the usage control is performed for the paid image playback processing in the distributed digital content. It is also possible to manage whether or not content editing processing is possible and to perform usage control for editing processing of image data stored in the actual image portion.

As shown in FIG. 13, when the distributed digital contents are an image a and an image b composed of a CM image and a pay image, the editing permission condition which is permission information for the editing process for each of the images a and b a and b are set.
Each editing permission condition a, b is managed as editing permission information for each user by an editing permission table as shown in FIG. In the editing permission table of FIG. 14, user 1 is permitted to edit image a and image b, and user 2 is permitted to edit only image b.

When such an editing permission table is managed and use control for image data editing processing by the user is performed, the digital content can be used by the user according to the procedure shown in FIG.
Usage control related to image data editing processing can be executed via a dedicated application installed in a computer terminal used by a user, and a terminal equipped with such an application is referred to herein as editing permission means.

  When an image including a CM part and a pay part is input, the editing permission unit performs real image information stored in the real image part 110 for each image and a data expansion part according to the same procedure as in FIG. The data extension information stored in 120 is separated, and then the data extension information is separated into the encrypted image part 121 and the data reproduction information part 122. Further, an encryption key embedded as an invisible digital watermark is extracted from the actual image stored in each actual image unit 110, and the encrypted image stored in the encrypted image unit 121 is decrypted.

The editing permission means accepts the user ID input by the user, accesses the user information database managed by the operation monitor 40 (see FIG. 1), etc., and applies the corresponding usage right of the received user ID. Browse information.
If the user ID input by the user is blank or invalid, the editing permission unit rejects the use of the image data and displays that effect.

If the user ID input by the user is not permitted to edit the image data, the edit permission means permits only the CM image reproduction process in the real image unit 110.
If the user ID input by the user is permitted to edit the image data, the editing permission means permits the user to edit the decrypted pay image. Of course, the user is permitted to perform the reproduction process of the CM image, and it is also possible to allow the CM image to be edited.

Further, when the data structure of the distributed digital content is configured to include a real image part, a data extension part, and a second data extension part as shown in FIGS. 11 and 12, it is set to the user who is the distribution destination. The usage right information related to the editing process according to the edited permission information can be configured to be stored in the second data extension unit as metadata.
In this case, usage right information including editing permission / non-permission information set for the user for each distributed image data is stored in the second data expansion units 260 and 270, and the user uses the image data. When there is an instruction, by referring to the usage right information stored in the second data expansion units 260 and 270, it is possible to perform usage control for permission to edit image data for the user.

For example, when the usage right information stored in the second data expansion units 260 and 270 is “not editable”, only the reproduction processing of the real image units 210 and 230 is permitted. In addition, in the type 1 data shown in FIG. 11, when the usage information stored in the second data expansion unit 260 is “editable”, the encrypted data stored in the encrypted image unit 121 is decrypted. The editing of the decrypted image data is permitted. In the type 2 data shown in FIG. 12, when the usage information stored in the second data expansion unit 270 is “editable”, the encrypted data 241 stored in the encrypted image unit 121 is decrypted. After that, it is combined with the CM window 240 of the real image section 230, and editing of this image data is permitted.
<Appendix>
(Appendix 1)
A data operation method for distributing digital content including moving image data,
Converting the first data licensed based on predetermined conditions into encrypted first data with a predetermined encryption key;
Generating watermarked second data in which the encryption key is embedded as an invisible digital watermark in second data that is unconditionally licensed;
Synthesizing and distributing the encrypted first data and the watermarked second data;
Data management method including

(Appendix 2)
The first data is encrypted with a different encryption key for each frame, the first encryption key obtained by encrypting the first frame is embedded in the second data as an invisible electronic watermark, and the second and subsequent encryption keys are encrypted. The data operation method according to appendix 1, wherein encryption key generation information obtained by a logical operation with the first encryption key is stored in a header of each frame image.

(Appendix 3)
The data operation method according to appendix 1 or 2, wherein the second data is advertisement information.
(Appendix 4)
Sending usage permission information of the first data to a user in response to billing payment;
Discounting the billing according to the usage time or the number of uses of the second data;
The data operation method according to attachment 3, further comprising:

(Appendix 5)
Authenticating whether or not a user to whom the digital content is distributed satisfies a predetermined condition for using the first data;
Based on an authentication result as to whether or not the user satisfies a predetermined condition for using the first data, causing the user to use the digital content by a corresponding usage method;
The data operation method according to attachment 1, further comprising:

(Appendix 6)
The data operation method according to appendix 5, wherein the user is made to use the first data by a reproduction process based on the authentication result.
(Appendix 7)
6. The data operation method according to appendix 5, wherein the user is caused to perform an editing process on the first data based on the authentication result.

(Appendix 8)
A data operation method for distributing digital content including moving image data,
Converting the first data licensed based on predetermined conditions into encrypted first data with a predetermined encryption key;
Generating second data to be used unconditionally and third data in which the encryption key is embedded as metadata;
Synthesizing and distributing the encrypted first data, second data and third data;
Data management method including

(Appendix 9)
The data operation method according to appendix 8, wherein the third data includes usage right information including permission information on whether or not to permit use of the first data as metadata.
(Appendix 10)
The data operation method according to appendix 9, wherein the usage right information includes permission / prohibition information for the reproduction process of the first data.

(Appendix 11)
The data operation method according to appendix 9, wherein the usage right information includes information on whether or not the first data can be edited.
(Appendix 12)
A data utilization device for using digital content including encrypted first data obtained by encrypting first data with a predetermined encryption key and watermarked second data in which the encryption key is embedded as an invisible electronic watermark. And
An encryption key extracting means for extracting an encryption key from the watermarked second data;
Data decrypting means for decrypting the encrypted first data into first data using the encryption key extracted by the encryption key extracting means;
Authentication means for authenticating whether or not a predetermined condition for using the first data is satisfied;
Based on the instruction from the user and the authentication result by the authentication means, the first data is decrypted by the encryption key extraction means and the data decryption means, and the decrypted first data is reproduced and output, or Data output means for reproducing and outputting the second data;
A data utilization device comprising:

(Appendix 13)
13. The data utilization apparatus according to appendix 12, further comprising time management information recording means for storing time management information based on a use time or a use count for each data included in the distributed digital content in a predetermined area of the data.
(Appendix 14)
14. The data utilization apparatus according to appendix 13, further comprising time management information output means for outputting time management information stored in a predetermined area of the data for billing management.

(Appendix 15)
15. The data utilization apparatus according to appendix 13 or 14, wherein the time management information recording unit embeds time management information for each data as an invisible digital watermark in the second data.
(Appendix 16)
The data utilization device according to supplementary note 15, further comprising falsification detection means for comparing the time management information stored in a predetermined area of the data with reference information relating to a utilization situation owned by each data and verifying the presence or absence of falsification.

(Appendix 17)
Any one of appendices 12 to 16, wherein the authentication means accesses an operation monitoring server that manages management information including permission information of each data, and authenticates the permission information by referring to the management information of the operation monitoring server. The data utilization device described in the above.
(Appendix 18)
18. The data utilization apparatus according to any one of appendices 12 to 17, further comprising an edit permission unit that permits an edit process of the first data based on an authentication result by the authentication unit.

(Appendix 19)
Program of data utilization apparatus for using digital content including encrypted first data obtained by encrypting first data with a predetermined encryption key and watermarked second data in which the encryption key is embedded as an invisible digital watermark Because
An encryption key extracting means for extracting an encryption key from the watermarked second data;
Data decrypting means for decrypting the encrypted first data into first data using the encryption key extracted by the encryption key extracting means;
Authentication means for authenticating whether or not a predetermined condition for using the first data is satisfied;
Based on the instruction from the user and the authentication result by the authentication means, the first data is decrypted by the encryption key extraction means and the data decryption means, and the decrypted first data is reproduced and output, or Data output means for reproducing and outputting the second data;
A program for causing a computer to function as a data utilization device.

  In the present invention, the encryption key when the first data such as the pay image is encrypted is embedded as an invisible digital watermark in the second data that can be used unconditionally such as advertisement information, and the security of the first data is increased. It can be maintained at a high level, and the right of digital data can be protected by preventing falsification of information. In addition, it is possible to legitimately obtain the evaluation of the data content by the content user, and it is possible to improve the convenience of the content provider during distribution. In addition, the content user can obtain as much information as he wants and can reduce the billing amount to the minimum necessary. When advertising information is used as the second data, the billing amount is further suppressed, and the convenience for the content user is further improved.

It is explanatory drawing which shows the example of a mode of the business model by which 1 embodiment of this invention is employ | adopted. It is explanatory drawing of the data structural example of the digital content distributed. It is explanatory drawing which shows an image reproduction process. It is explanatory drawing which shows the outline | summary of the image reproduction process based on usage right information. It is explanatory drawing which shows 1 form of an image format. It is explanatory drawing which shows 1 form of an image format. It is explanatory drawing which shows the outline | summary of the encryption key generation process at the time of pay image reproduction | regeneration. It is explanatory drawing which shows a content utilization management process. It is explanatory drawing which shows the system used for verification experiment. It is explanatory drawing which shows the example of image reproduction. It is explanatory drawing which shows 1 form of the image format used for other embodiment. It is explanatory drawing which shows 1 form of the image format used for other embodiment. It is a data structure of the digital content used for other embodiment. It is explanatory drawing of an edit permission table. It is explanatory drawing of the procedure which performs the edit permission of the distributed image data.

Claims (6)

A data utilization device for using digital content including encrypted first data obtained by encrypting first data with a predetermined encryption key and watermarked second data in which the encryption key is embedded as an invisible electronic watermark. And
An encryption key extracting means for extracting an encryption key from the watermarked second data;
Data decrypting means for decrypting the encrypted first data into first data using the encryption key extracted by the encryption key extracting means;
Authentication means for authenticating whether or not a predetermined condition for using the first data is satisfied;
Based on the instruction from the user and the authentication result by the authentication means, the first data is decrypted by the encryption key extraction means and the data decryption means, and the decrypted first data is reproduced and output, or Data output means for reproducing and outputting the second data;
Time management information recording means for recording time management information based on the usage time or the number of usages for each data included in the distributed digital content as a usage history;
A data utilization device comprising:   The data utilization apparatus according to claim 1, further comprising time management information output means for outputting the usage history recorded by the time management information recording means for billing management.   2. The data use apparatus according to claim 1, wherein the time management information recording unit extracts time management information for each piece of data embedded as an invisible digital watermark in the second data and records it as a use history. .   The data utilization apparatus according to claim 2, further comprising a falsification detection unit that compares the time management information with reference information related to a use situation owned by each data and verifies whether or not falsification has occurred. Executed in a data utilization device for using digital content including encrypted first data obtained by encrypting first data with a predetermined encryption key and watermarked second data in which the encryption key is embedded as an invisible digital watermark Data usage method,
Extracting an encryption key from the watermarked second data;
Decrypting the encrypted first data into first data using the encryption key extracted by the encryption key extracting means;
Authenticating whether a predetermined condition for using the first data is satisfied;
Based on an instruction from a user and an authentication result by the authentication means, decoding the first data and reproducing and outputting the decrypted first data, or reproducing and outputting the second data;
Recording time management information based on the usage time or usage count for each data contained in the distributed digital content as a usage history;
A data utilization method comprising: Executed in a data utilization device for using digital content including encrypted first data obtained by encrypting first data with a predetermined encryption key and watermarked second data in which the encryption key is embedded as an invisible digital watermark A data utilization method program,
Extracting an encryption key from the watermarked second data;
Decrypting the encrypted first data into first data using the encryption key extracted by the encryption key extracting means;
Authenticating whether or not a predetermined condition for using the first data is satisfied;
Based on an instruction from a user and an authentication result by the authentication means, executing decoding of the first data and reproducing and outputting the decoded first data, or reproducing and outputting the second data;
Recording time management information based on the usage time or the number of times of use for each data included in the distributed digital content as a usage history;
A program for causing a computer to execute a data utilization method.

Images