JPH09138827A - Digital copyright distribution system - Google Patents

Abstract

(57) [Abstract] [Problem] To protect the rights and interests of the information provider, a digital work distribution system that obliges the user to obey the usage contract and pay the correct price when using the work is simple. It is provided with an inexpensive configuration. SOLUTION: A distribution center device edits and edits original data to create distribution data, manages a history of the editing and editing, and stores a program for restoring the original data from the distribution data in the editing history. A means for creating with reference, a means for setting conditions for using a digital work on a user device, a means for creating an object encapsulating the restoration program and the usage conditions, and encrypting the object. And a means for decrypting the encrypted data, a means for determining availability based on a usage condition in the object, and a restoration program based on the determination result. Means and means for reproducing the restored data are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for distributing digital works such as texts, images and moving images, and in particular, provides information by preventing a user from violating a usage contract when using a work. The present invention relates to a digital work distribution system that protects the rights and interests of persons.

[0002]

2. Description of the Related Art In recent years, with the progress of digitization of information, the provision of information by CD-ROM and networks has become popular. In particular, with the popularization of multimedia titles and the emergence of video journalists, it is expected that information provision using images and moving images will become active in the future. In the present invention, these digitized images and moving images and multimedia titles created using them are called digital works.

In order for the service for providing this digital work to be established as a business, it is necessary to have a mechanism for protecting the copyright of the information provider and legally paying the fee such as the information providing fee to the provider. Unless the environment where information can be provided with peace of mind is established, good quality information cannot be collected and the amount of information handled is limited. Therefore, the number of users does not increase, and the business does not start up. On the other hand, in an environment where the rights and profits of information providers are guaranteed, a large amount of good quality information will be collected, and as a result, the number of users will increase.
In addition, the market principle will eventually work and information will be provided at low cost, which will increase the merits for users and may further expand the business.

The most serious problem in the distribution of this digital copyrighted work is copying (illegal copying) performed by a user without permission of the copyright holder. Since digital data can be easily copied, copyright infringement due to illegal copying has been a problem. In a networked society, illegal copies may be scattered everywhere through the network,
The problem becomes more serious.

As a conventional technique for preventing illegal copy,
It is common to add copy protection hardware to a device that reproduces a work. For example, Nikkei Electronics (Nikkei BP) November 21, 1994 issue (no.
622), a television signal processing LSI that generates a copy disturbing signal in digital satellite broadcasting is provided in a set top box (home satellite broadcasting reproducing apparatus) so that a user cannot cleanly record a broadcasting program. Also, in DAT (Digital Audio Tape recorder) etc., SCM that digital copy is permitted only once.
A device configuration by the C (Serial Copy Management System) method is obligatory.

[0006] On the other hand, there is also an approach that makes illegal copying meaningless by constructing a system that collects a fee according to the frequency of use. For example, Japanese Unexamined Patent Publication No. 64-68835 discloses a software rights management control method for charging by using an encryption system in which a plain text (decrypted information) is obtained only in a dedicated processor incorporated in the apparatus. . With this method, each time the decryption process is performed by the dedicated processor,
The frequency of use is calculated assuming that the information has been used. Then, a fee according to the frequency of use is collected from the user.
Since all information distributed is encrypted, the copy itself is not useful. To use it, it is necessary to decrypt it with a dedicated processor, but since the frequency of use is counted each time it is decrypted, the usage fee will be paid as a result. Generally, a digital work distribution system using this method is called a super distribution system.

As described above, the prior art relating to the distribution system of digital copyrighted works is described in the above-mentioned Nikkei Electronics (Nikkei BP) November 21, 1994 issue (No. 62).
Details on 2).

[0008]

However, both of the conventional techniques require dedicated hardware. In particular, in the super distribution system, it is necessary to incorporate the dedicated processor into the devices of all users, so that there is a problem that the introduction cost becomes high. Further, when new hardware is introduced, the configuration of the entire device becomes complicated, and as a result, the functions are limited and the usability and reliability of the user are reduced.

Further, when the above-mentioned approach to prevent illegal copying is applied to a computer, since the copy function is already a function of the OS (operating system), it is necessary to replace the OS newly. The introduction cost will also be high. In other words, in order to prevent illegal copying with the conventional technology, there is a problem that the user has to make major changes to the hardware and software assets that he or she is accustomed to.

On the other hand, in the conventional digital work distribution system such as the super distribution system, it is premised that all works are encrypted and distributed. Depending on the encryption method, generally, the stronger the encryption, the greater the overhead for decryption. For this reason, it takes time for the user to decrypt the encrypted data, and in the conventional technology, there is a problem that a dedicated decryption hardware is required to solve this.

Further, the content of the encrypted data cannot be reproduced unless it is decrypted, so that the user cannot easily confirm the content of the information. When purchasing a product, it is common to check the contents before purchasing. In particular, when using visual information such as an image or a moving image, it is difficult to determine whether the information is what the user really wants, only from the description or the like. For this reason, in the conventional technology, a method is adopted in which a fee is charged from the second and subsequent decryption, and the user can confirm the content by the first decryption. However, humans are not rich in memory so that they can remember all the contents of information by just seeing them once. Especially, when you want to compare multiple images or moving images, or when you actually see images or moving images you saw before. However, there is a problem that the conventional technology cannot cope with the case where the user wants to search.

In view of the above-mentioned problems, the present invention makes a slight modification such as installation of distribution software without introducing new hardware to the system configuration currently used by the user and without limiting the functions. The first object is to provide a digital copyrighted material distribution system that guarantees the rights and profits of copyright holders.

A second object of the present invention is to provide a digital copyrighted material distribution system which prevents illegal copying without significantly changing the hardware and software assets used by the user.

A third object of the present invention is to provide a digital copyrighted work distribution system in which the overhead of encryption or decryption is minimized without using dedicated encryption or decryption hardware. To do.

A fourth object of the present invention is to provide a digital work distribution system which allows a user to easily confirm the contents of the digital work while protecting the copyright of the work.

[0016]

In order to achieve the above object, the first device according to the present invention (hereinafter referred to as "distribution center device") has means for processing and editing original data to create distribution data. (Hereinafter referred to as "processing and editing means") and means for managing the processing and editing history (hereinafter, referred to as "processing and editing means").
"Edit history management means"), means for creating a program for restoring original data from distribution data by referring to the history of processing and editing (hereinafter referred to as "restoration program creation means"), original data and distribution data When a digital work is used by means for creating difference data, which is the data obtained by taking the difference (hereinafter referred to as "difference data creation means"), and a second device (hereinafter referred to as "user device") Means for setting the conditions (hereinafter, referred to as “usage condition setting means”), a restoration program creating means, a difference data creating means, and a usage condition setting means, and the created restoration program and difference data are set. Means to create encapsulated objects with usage conditions (hereinafter referred to as "restoration object creation unit")
And means for encrypting the object (hereinafter referred to as "encryption means"). Also, in the user device,
A means for decrypting encrypted data (hereinafter, "decryption means")
And a means for determining availability based on the usage conditions in the object (hereinafter referred to as "usage condition determining means")
And means for executing the restoration program based on the judgment result (hereinafter referred to as "restoration program execution means"),
A means for reproducing the restored data (hereinafter referred to as "restored data reproducing means") is provided.

The processing / editing means processes and edits the original data by a predetermined method to create distribution data. The restore object creating unit creates a restore object by encapsulating the restore program and the difference data created by the restore program creating means and the difference data creating means together with the usage conditions set by the usage condition setting means. The encryption means encrypts the restored object to create encrypted data.

The decryption means decrypts the encrypted data sent from the distribution center device to make the restored object into the original plaintext. The restoration program execution means converts a restoration object that has become a plain text, a restoration program, difference data,
The usage condition is retrieved, and the original data is restored from the distribution data by using the restoration program and the difference data according to the determination result obtained by the usage rule determining means based on the retrieved usage condition.

Here, the distribution center device may be provided with means for designating the data to be written in the original data by the copyright holder (hereinafter referred to as "write data designating means"). At this time, the processing / editing means transforms the write data based on the format desired by the copyright holder designated by the write data designating means, determines the area in the original data in which the transformed write data should be written, and The original data portion belonging to is cut out and secured in the memory, and the write data is written in the area. When the difference data creating means creates the difference data later, the original data portion reserved in the memory may be used.

Further, the user device includes means for editing the restored original data to create secondary data (hereinafter referred to as "restored data editing means"), and means for managing the editing history at that time. A means for creating a program for automatically generating secondary data from the restored data by referring to the editing history may be provided. At this time, when the secondary data is distributed via the distribution center device, the secondary data creation program is also encrypted and distributed.

Further, the write data designating means may set the shape of the display area of the write data according to the designation of the copyright holder.

Further, the write data designating means stores the copyright holder designating information consisting of the write data desired by the copyright holder, the size of the write data and the area in the original data in which the write data is written, for each copyright holder. A copyright holder designation information storage means may be provided. At this time,
Each time the original data is registered in the distribution center device, the processing / editing means refers to the copyright holder designation information storage means, and writes the corresponding write data based on the copyright holder designation information corresponding to the registered copyright holder. Write to the original data. As the write data, information generated from a character string or a symbol string that identifies the copyright holder registered in the copyright holder designation information may be used as the write data.

The encryption means encrypts the restored object with the user's public key to create encrypted data, and the decryption means decrypts the encrypted data with the user's private key to restore the restored object. You may make it plain text.

Further, the period of use for the user is set in the use condition, and the use condition determining means has a date and time detecting means for detecting the date and time when the decrypting means decrypts the encrypted data. It is also possible to compare the date and time detected by and the period indicated by the description included in the usage condition related to the decrypted encrypted data, and determine whether the date and time is within the period.

The most important feature of the present invention is that the completeness of the digital work can be controlled only by the author or a trusted third party, and the digital work can generally be distributed only in an incomplete form. That is the point. In particular,
Instead of distributing digital works such as images and moving images as they are, distribute data that has been processed to reduce the amount of information so that the content can be confirmed. Although the distributed data has the effect of advertising as a sample version, it is not at a level where the copyright is infringed by unauthorized use, so illegal copying can be rendered meaningless.

On the contrary, by embedding the copyright information in the distributed data, the assertion of the copyright can be strengthened. For example, the copyright display is directly embedded as an image in an image or a moving image. By doing so, the user will always be aware of who the distributed data belongs to when using the data.

In order to restore the distributed incomplete data, the user needs to separately obtain a restore program based on a usage contract and, in some cases, difference data that is the difference between the original data and the distribution data. There is. In other words, the user must pay the price in order to formally use the digital work. At this time, the user does not obtain the digital work itself by paying the price, but obtains the right to use the work. Based on this idea, in the present invention, the usage program according to the usage contract is passed to the user. For example, when the right to refer to a digital work is purchased, a program for reproducing data is sent together with a program for restoring original data from incomplete distribution data. On the other hand, when the right to use the digital work secondarily is purchased, the program for editing the data is sent together with the program for restoring the original data from the incomplete distribution data. Here, the reproduction program and the editing program may be held in the user device in advance, and the distribution center device may be provided with an interface for passing the restoration program together with the restoration program to either of the above two programs.

In the digital copyrighted material distribution system according to the present invention, how to easily create the above-mentioned restored object and to protect it from fraud is important. Therefore, the present invention adopts the following configuration.

First, from the viewpoint that a restored object should be created easily, the present invention provides an editing history management means in the distribution center device, and when the distribution center device edits and edits original data to create distribution data. The editing history is stored so that the restoration program and the difference data can be easily created from the editing history. Specifically, each time an editing operation is performed, the reverse operation and related data are saved, and redundant operations and the like are appropriately deleted from the saved operations and related data columns when the editing operation is completed. A restoration program and difference data are created based on the operation sequence and data obtained in this way.

Further, from the viewpoint that the restored object should be protected from illegality, firstly, the present invention encrypts the restored object when it is provided to the user. In addition, the public key encryption method is adopted as the encryption method, and the restored object is encrypted with the public key for each user. By doing so, the user cannot decrypt the data other than his / her own private key. Therefore, even if another person copies the restored object, he / she cannot enjoy the service unless he / she simultaneously obtains the private key of the user who purchased it legally. Further, since this restored object is protected by encryption, it is almost impossible to tamper with it. Similarly, even if the distribution data is tampered with, there is a high possibility that the restoration program will not operate correctly, so tampering with the original data is impossible. Second, the present invention encapsulates the usage rule as a restore object and encrypts it. By doing so, it is impossible to tamper with the usage conditions, and it is possible to almost completely prevent the user from breaching the usage contract.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In the present embodiment, a still image will be described as a representative example of digital works. In the case of another digital work such as a moving image, the moving image may be considered as a continuous set of still images and may be implemented with the same configuration as that of this embodiment. In the case of texts, voices, multimedia titles, and the like, description will be appropriately added only to the portions of the present embodiment that are different in configuration from the still image.

First, the outline of this embodiment will be described.

FIG. 1 is a diagram showing the basic configuration of a digital copyrighted material distribution system according to this embodiment. This system comprises a distribution center device 10 for distributing a digital work and a user device 70 for using the digital work.

The literary work provider registers the original data 1 of the digital literary work in the distribution center device 10. The distribution center device 10 creates the distribution data 3 based on the registered original data 1 by reducing the amount of information to the extent that the content can be confirmed. The distribution data 3 is presumed to be distributed to the general public free of charge, and is mainly used for advertising purposes.
In addition, the copyright provider provides copyright display data 2 which is information regarding the copyright of the digital copyrighted work to the distribution center device 1.
By registering in 0, the distribution center device 10 directly embeds the copyright display data 2 in the original data 1 to create the distribution data 3. Since the copyright display data 2 is directly embedded in the distribution data 3, the user always uses the distribution data 3 while being aware of the copyright display portion 4. Therefore, it has the effect of enhancing the advertising effect and clarifying the ownership of the rights of the copyrighted work.

When the user wants to use the digital work based on the usage contract 61, the user pays some consideration,
The program 41 and the difference data 42 for restoring the distribution data 3 to the original data 1 are obtained. These are encapsulated as the restoration object 40 together with the usage condition 43 which is a condition for use, and are sent to the user as encrypted data 52. Here, the user is not the data obtained by encrypting the original data 1 itself, but the difference data 42 created by subtracting the difference between the original data 1 and the distribution data 3 and the original data 1 by embedding it in the distribution data 3. To restore to 41
The feature of the present invention lies in the encryption. This prevents the original data 1 from being completely out of the control of the distribution center device 10. Further, as compared with the case where the original data 1 itself is encrypted, since the amount of information to be encrypted is small, there is an effect that the overhead required for decryption is reduced.

The restoration object 40 also includes a usage rule 43 based on a usage contract 61, and the user device 70 interprets this and determines the availability and the usage authority. As the determination of availability, for example, when the usage period is set as the usage condition 43, the user device 70 compares the current date and time when the encrypted data 52 of the restored object 40 is acquired with this usage period, If the current date and time is within the use period, it is determined to be usable, and if it is outside the use period, it is determined to be unavailable. On the other hand, as the determination of the usage authority, for example, the user device 70 limits the functions or ranges that can be used based on the usage contract including the consideration paid for the usage.
That is, the purpose of use of a digital work mainly includes appreciation and reference and secondary use by processing and editing. In terms of use condition 43, whether the appreciation and reference are permitted or the secondary use by processing and editing is permitted. By describing the permission range of the authority as to whether the user device 70
Determines the usage authority of the corresponding user and limits the functions that the user can operate with the user device 70. By doing so, the original data 1 is also stored in the user device 70.
It is possible to guarantee the prevention of unauthorized copying and tampering.

Next, details of this embodiment will be described.

The distribution center device 10 edits the original data 1 and creates the distribution data 3 by creating the distribution data creation unit 20, the restoration program 41 and the difference data 42 together with the usage condition 43 and the restored object 4.
It has a restored object creation unit 30 that creates 0, an encryption unit 50 that encrypts the restored object 40, and a usage management unit 60 that manages a usage contract 61 with a user.

The distribution data creating section 20 includes a data cutting means 22 for processing and editing, a data writing means 23,
The data transformation unit 24 and the editing history management unit 21 that manages the history of the editing work by the respective units 22 to 24 are provided. Each of these means 22 to 24 is used to edit the original data 1 so as to reduce the amount of information of the original data 1 so that the content can be confirmed, and to write the copyright display data 2 by transforming it so as to match the size of the original data 1. To use.

The restore object creating unit 30 creates a restore program 41 for reproducing the original data 1, restore program creating means 31, original data 1
And a difference data creating means 32 for creating difference data 42 from the distribution data 3 and a usage condition setting means 33 for setting usage conditions 43. Restoration program creation means 31
The difference data creating means 32 creates the restoration program 41 and the difference data 42 by referring to the edit history up to that point. Since this edit history is managed by the edit history management means 21 as a series of edit commands arranged in the data edit order, the restoration program creating means 31 and the difference data creating means 32 refer to this edit command series in the new order. At the same time, the redundant command is removed, and the restoration program 41 and the difference data 42 are created so that the distribution data 3 can be restored to the original data 1 in order. Here, the difference data 42 is the distribution data 3 by the restoration program 41.
Created as what should be inserted in the proper position of.
The usage condition setting means 33 sets a plurality of usage conditions 43 in advance, and encapsulates these usage conditions 43 together with the restoration program 41 and the difference data 42 as a restoration object 40. Since the usage period and the like need to be updated each time the user makes a usage contract, the usage condition setting means 33 is linked to the usage management means 60 so that the usage condition 43 can be set correctly.

The restored object 40 created through the above process is encrypted by the encrypting means 50.
And is supplied to the user device 70. At present, a wide variety of encryption methods are known, but the public key encryption method is used here. The public key cryptosystem is a system in which a pair of keys of a public key and a secret key are prepared, and encryption is performed on the one hand and decryption is performed on the other. The public key is a public key, and the private key is a key known only to the user. In this embodiment, the encryption key 51 is a public key and the decryption key 54 is a secret key. Therefore, the decryption can be performed only by the private key of the user. Therefore, even if the user illegally copies the encrypted data 52 and transfers the encrypted data 52 to another person, the transferred other person decrypts the encrypted data 52 and the contents thereof unless the private key of the user is disclosed at the same time. Can't see. That is, the illegal copy is meaningless. A key management organization 55 operated by a reliable third party is provided in order to manage the public key and private key for each user.

The user device 70 includes the distribution data reproducing means 24 for reproducing the distribution data 3, the use transmitting means 62 for the user to apply for the use of the digital work, and the encrypted data 52 to be obtained after the use application. It has a data reproducing section 80 for reproducing the original data 1 by reproducing it from the distribution data 3.

The distribution data reproducing means 24 is composed of a normal image display program. As described above, the distribution data 3 should be mainly used for advertising purposes, and it may be difficult to obtain a sufficient advertising effect if special software is required to reproduce the distribution data 3. To be Therefore, the distribution data 3 is general-purpose image data so that it can be reproduced by an image display program that is widely used by users, such as the distribution data reproducing means 24.

The use transmission means 61 is means for sending the use contract 61 to the distribution center device 10 before receiving the service, and is constituted by an online transmission device such as electronic mail or an offline transmission device such as an application form. The user is the usage contract 61 created by the usage communication means 61.
Based on, pay the copyright provider. An electronic transaction device to which elemental technologies such as electronic money and user authentication are applied may be used as the usage communication means 61. Further, as the most reliable method, a method of combining the use communication by mailing the application form and the payment of consideration by bank transfer may be adopted.

The data reproducing section 80 includes a decrypting means 53, a restoring program executing means 81, a usage condition judging means 82, a restored data reproducing means 83, and a restored data editing means 84.
Having. As described above, the decryption means 53 decrypts the encrypted data 52 using the decryption key 54 which is the user's secret key.

The use condition determining means 82 checks the current state of the user device 70 for each item in the use condition 43, compares it with the use condition 43 in the restoration object 40, and determines whether the current state satisfies the use condition 43. Determine whether or not. For example, when the usage period is set as the usage condition 43, it is determined whether the usage date and time is within the usage period. When the current state satisfies the usage condition 43, the restoration program execution means 81 executes the restoration program 41.
When executing the restoration program 41, the distribution data 3 is required in addition to the restoration program 41 and the difference data 42. The distribution data 3 should have already been distributed to the user at this point, but in consideration of the case where the distribution data 3 is lost or damaged, or when the user contracts to use without receiving the distribution data, etc. The distribution data 3 may also be sent to the user.

The restored data reproducing means 83 is a program for reproducing and displaying the restored original data 1. Similarly, the restored data editing means 84 is a program for editing the restored original data 1. The usage condition judging means 82 judges which program may be used by the user according to the usage condition 43 based on the usage contract 61, and switches the program selection switch 85 to restore data reproducing means 83 or restored data editing means. The restored original data 1 is passed to any of 84. The restored data reproducing means 83 and the restored data editing means 84 include a decrypting means 53 for the encrypted data 52 and a use condition determining means 8
2 and the restoration program executing means 81 are all embedded in the data reproducing section 80 as a single program, so that the user can save the decrypted restoration object 40 to a local disk for an unauthorized purpose, or can save the contents. It has the advantage that it is difficult to tamper with.

FIG. 2 is a view showing a display example of distribution data 3 distributed to users in the digital copyrighted material distribution system according to this embodiment. First, the display example 9 of FIG. 2 (A)
Copyright notices 100 to 102 are embedded in 0.
It is characterized in that a plurality of copyright notices 100 to 102 are dispersed and embedded in the entire image of the original data 1 in order to clarify where the copyright belongs and to prevent secondary use due to falsification.

A mark 103 of the copyright holder is embedded in the display example 91 of FIG. 2 (B). In the display example 90, the text relating to the copyright display is converted into an image and embedded in the original data 1. However, by directly embedding an image such as the mark 103 of the copyright holder's personal symbol, There is an advantage that the distribution data 3 can be viewed in a natural form. In paintings and calligraphy, it is common to put the author's signature or stamp on the work, but this is intended for digital works such as still images and moving images.

Further, in the display example 92 of FIG. 2C, the copyright notice 104 is inserted as image data in the form of a character font instead of rectangular image data. Here, the image data is not limited to the character font shape, and various other shapes of image data may be inserted. Since various types of image data are embedded, compared to the case where rectangular image data is embedded,
Although the restoration program 41 tends to be complicated, there is also an advantage that it is possible to effectively prevent tampering by the user and unauthorized restoration of the original data 1. Also,
By making the style of each character font bag-shaped and emphasizing only the character frame to expose the background pattern inside, the restoration process can be further complicated.

Further, in the display example 93 of FIG. 2D, although the data relating to the copyright is not particularly displayed, the image 105 hides the eye portion indispensable for identifying the human face. As you can see, there are parts of the image that play a central role in making sense, which you can specify manually or automatically,
By hiding the relevant part by cutting it out, it is possible to create the distribution data 3 in which the contents can be confirmed to some extent but the amount of information is greatly reduced. The same idea is basically applied to digital works of other media, and the data in which the part playing the central role in the work is hidden is generally distributed. As described above, the distribution data 3 has an advertising effect, and a user who is interested in seeing the distribution data 3 makes a contract with the copyright provider and pays a price to convert the distribution data 3 into the original data 1. The restoration object 40 to be obtained is obtained.

Next, the processing for distributing a digital work in the digital work distribution system according to this embodiment will be described.

FIG. 3 is a flowchart showing the digital copyrighted material distribution processing 110 executed by the distribution center apparatus 10. First, the original data 1 is input (step 111). Here, the management table 150 expressing the configuration of the original data 1 is shown in FIG. The original data 1 is a dot position in each of the X direction 151 and the Y direction 152 and a pixel value (RGB value) 1 at that position.
It is represented by a set of 53. The pixel value 153 is represented by a total of 3 bytes of R, G, B and 1 byte each, and each value is represented by a hexadecimal number here. For example, in row 154, dot position (X, Y) = (610, 451)
The pixel values of R = 3F, G = B2, and B = 56. Regarding the expression style of this pixel value 153, FIG.
The same applies to FIG.

Next, the copyright display data 2 is read (step 112). As described in the description of FIG. 2, the copyright display data 2 includes data generated by converting a text relating to copyright into an image, and image data such as an icon which is used as a substitute for the copyright display. In any case, each time the copyright holder registers a digital work in the distribution center device 10, the copyright display data 2 is input, or the copyright holder registers in advance and stores it in a disc or the like. It is necessary to read out the copyright notice data 2 from the disc.

Next, the write condition of the copyright display data is set (step 113). As a writing condition,
Set the writing position, writing size, writing style, etc. For example, when the copyright display data 2 is text, the font type, size, and display style are set as the writing conditions. FIG. 5 shows that the dot positions represented by rows 154-156 are set as the cutout portion.

Next, according to the set write condition,
The copyright display data 2 is transformed (step 114). That is, the text is converted into an image according to the writing condition, or the image is enlarged or reduced to a size according to the writing condition.

Next, the original data 1 is cut out from the writing position set as the writing condition (step 115), and the copyright display data 2 is overwritten at the writing position (step 116). At this time, the cut-out original data portion is used later and is left in the memory. As described above, the distribution data is completed and is open to the public (step 117).

FIG. 6 is a diagram showing the management table 160 expressing the configuration of the distribution data 3. The structure is basically the same as that of the management table 150 of FIG.
The pixel value 153 of 66 is different from the pixel value 153 of the lines 154 to 156 of FIG. 5 set as the cutout position for displaying the copyright. Here, in order to simplify the explanation, all pixel values are unified to black (000000), but in reality, the copyright display data 2 is written here,
Not all pixel values are black (000000).

The processing from step 112 to step 117 is basically performed by the computer constituting the distribution data creating section 20. Therefore, the copyright holder must register the copyright display data 2 in advance and write the original data 1
It is assumed that the processing and editing work of is also programmed by the copyright holder. Of course, the programming work should be done interactively so that the burden on the copyright holder does not increase.

Next, the data left on the memory in step 115 is saved as difference data 42 (step 118). Similarly, a program for reflecting the difference data 42 in the distribution data 3 is created (step 11).
9). The structure of the difference data 42 is as shown in FIG. 7, but the basic structure is the management table 15 of FIG. 5 and FIG.
Similar to 0 and 160. However, since the difference value between the two is stored, the data size becomes considerably small. Simply, the difference between the management table 150 and the management table 160 is taken and the data other than where the value becomes 0 may be saved as difference data. Further, the restoration program 41 has a content such that the pixel value 153 is added to the pixel value 153 of the distribution data 3 for each dot position of the difference data 42. An example of the restoration program 41 is shown in FIG.

Next, the usage condition 43 is set (step 120). Items to be set in the usage conditions 43 are designated in advance by the copyright holder. Then, the conditions such as the usage period that need to be set at the time of the contract and the conditions that the user can select at the time of the contract such as the usable function range are set at the time of the contract, and the other conditions are set in advance. An example of the usage condition 43 is shown in FIG. Here, as the items of the usage rule 43, a usage period, a used machine name, and a used function are specified.

Next, the restoration program 41 and the difference data 4
2 and the usage condition 43 are encapsulated (step 12
1) Complete the restored object 40 (step 12)
2). Here, encapsulation means embedding a value in one data structure.

FIG. 7 is a diagram showing an example of the restoration object 40 formed by encapsulating the difference data 42, the restoration program 41, and the use condition 43 created in steps 118 to 120.

Finally, the restored object 40 is encrypted (step 123), and the process ends (step 12).
4). The encrypted restoration object 40 is transmitted to the user device 70 after waiting for a transmission request from the user.

Next, the processing when the user refers to a digital work in the digital work distribution system according to this embodiment will be described.

FIG. 4 is a flowchart showing the digital work reference processing 130 executed by the user device 70. First, the user obtains the distribution data and reproduces it on a trial basis (step 131). At this time, no special hardware or software is required, and in the case of an image, the user may have a normal image data display program. Since the distribution data obtained by the user is normal image data that has not been subjected to any special processing such as encryption, it can be reproduced normally by a general image data display program.

Next, the user applies for use of the desired image, concludes a use contract, and pays a consideration such as a use charge (step 132). This step could be performed by electronic transactions in the future due to recent advances in security technology.However, as mentioned earlier, mailing of contracts, bank transfer of usage fees, etc. You may perform by the method of.

When the encrypted restoration object 40 is sent from the distribution center device 10 (step 13)
3), the user device 70 first decrypts the encrypted data 52 to obtain a restored object (step 134).

Next, the usage condition 43 is obtained from the restored object 40 (step 135) and the current usage status of the user device 70 is obtained (step 136).
The usage condition 43 and the current usage status are compared with each other (step 137). Here, as the use condition items, as shown in FIG. 7, a use period, a use machine name, and a use function are set. Therefore, the date and time of use and the name of the machine in which the encrypted data 52 is installed are also acquired as the current use status. And, the date and time of use does not exceed September 20, 1995, and the machine used is yagaw.
Determine if it is a.hitachi.co.jp. If these usage conditions do not match the conditions, the process is terminated (step 1
38), if they match, the process is continued as it is (step 140).

Finally, the restoration program is executed to restore the original data 1 (step 141), and the original data 1 is reproduced (step 142).

In the usage rule 43 of FIG. 7, since the usable functions are limited to the reference functions only, the data reproducing section 80
The restored data reproducing means 83 in the inside is activated, but if the usage contract is made so that the editing function can also be used,
The restored data editing means 84 is activated. The restored data editing means 84 edits the restored original data 1 to create secondary data, manages the editing history at that time, and automatically generates secondary data from the restored original data 1. And a means for creating a program for making reference to the above-mentioned editing history. Here, when the secondary data is distributed via the distribution center device 10, the secondary data creation program is also encrypted and distributed.

Steps 134 to 142 described above
Up to this is the processing that the data reproducing unit 80 collectively performs. Since the present invention does not encrypt all the data but only the differential data, there is an effect that the decryption overhead in the decryption process of step 134 can be reduced.

In the present embodiment, a still image is taken as a digital work, but the present invention is not limited to this, and any digital information having a property as a work is used as a digital work in the present invention. May be treated as

[0074]

According to the present invention, since the copyright notice is embedded in the image data directly distributed to the user, the copyright of the copyrighted work provider can be effectively protected. Also,
When the user wants to see the original image, it is necessary to obtain the difference data and the restoration program, and therefore appropriate payment to the copyright provider can be expected. Furthermore, since the difference data is hidden in the program, it is almost impossible to illegally copy the original image unless a hard copy of the screen is performed, and the illegal copy can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a basic configuration of a digital work distribution system according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a display example of image data distributed to users in the digital copyrighted material distribution system according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a process when a digital work is distributed in a digital work distribution system according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a process when referring to a digital work in the digital work distribution system according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a configuration of original data in the digital copyrighted work distribution system according to the embodiment of the present invention.

FIG. 6 is an explanatory diagram showing a configuration of distribution data in the digital copyrighted work distribution system according to the embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a configuration of a restored object in the digital copyrighted material distribution system according to the embodiment of the present invention.

[Explanation of symbols]

 1 Original Data 2 Copyright Display Data 3 Distribution Data 4 Copyright Display Portion 10 Distribution Center Device 20 Distribution Data Creation Unit 21 Edit History Management Means 22 Data Extraction Means 23 Data Writing Means 24 Data Deformation Means 30 Decryption Object Creation Unit 31 Restoration Program Creation means 32 Difference data creation means 33 Usage condition setting means 40 Restoration object 41 Restoration program 42 Difference data 43 Usage conditions 50 Encryption means 51 Cryptographic key 52 Encrypted data 53 Decryption means 54 Decryption key 55 Key management organization 60 Usage management means 61 use contract 62 use transmitting means 70 user device 80 data reproducing section 81 decoding program executing means 82 use condition determining means 83 restored data reproducing means 84 restored data editing means 85 program selection switch 90 93 Display Example 100-102 copyright notice 103 mark 104 copyright 105 image 110 digital content distribution processing 130 digital content usage processing 150 Original data management table 160 distributes the data management table

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kunihiro Yanagi 1099 Ozenji, Aso-ku, Kawasaki-shi, Kanagawa Incorporated company Hitachi, Ltd. Systems Development Laboratory

Claims (11)

[Claims] 1. A first device for providing a digital work, which is a digitalized work, having at least a memory for storing digitized data, and connected to the first device by a communication means. And a second device for utilizing the digital work provided by the first device, wherein the first device processes and edits original data to create distribution data. Processing and editing means, means for managing the history of the processing and editing, means for creating a restoration program for restoring the original data from the distribution data by referring to the editing history, the original data and the distribution data Difference data creating means for creating difference data, which is data obtained by taking the difference between the two, and a digital work is used by the second device. A means for setting a usage condition that is a condition for creating a restoration object, a means for creating a restoration object that encapsulates the restoration program, the difference data, and the usage condition, and an encryption means for encrypting the restoration object. The second device has a decryption unit that decrypts the encrypted data, a unit that determines availability based on a usage condition in the restoration object, and executes the restoration program based on the determination result. And a means for reproducing the original data restored by executing the restoration program. 2. The digital work distribution system according to claim 1, wherein the second device edits the restored original data to create secondary data, and edit history at that time. It has means for managing and means for creating a program for automatically generating secondary data from the restored data by referring to the editing history, and in the case of distributing the secondary data via the first device, A digital copyrighted material distribution system characterized in that secondary data creation programs are also encrypted and distributed. 3. The digital copyrighted work distribution system according to claim 1, wherein the first device has write data designating means for designating write data to be written in the original data by the copyright holder, The processing / editing means transforms the write data based on the format designated by the write data designating means, determines an area in the original data in which the transformed write data is to be written, and belongs to the determined area. A digital copyrighted work distribution system, characterized in that an original data portion is secured in the memory and the write data is written in the determined area. 4. The digital copyrighted material distribution system according to claim 3, wherein the difference data creating means creates the difference data based on an original data portion secured in the memory. Copyright distribution system. 5. The digital work distribution system according to claim 3, wherein the write data designating unit sets the shape of the display area of the write data according to designation by the copyright holder. Digital copyright distribution system. 6. The digital copyrighted work distribution system according to claim 3, wherein the write data designating means is the write data desired by a copyright holder, the size of the write data, and the write data. Has copyright holder designation information storage means for storing copyright holder designation information composed of an area in the original data for each copyright holder, and the processing and editing means stores the original data in the first device. Each time registration is performed, the copyright holder designation information storage means is referred to, and corresponding write data is written in the original data based on the copyright holder designation information corresponding to the registered copyright holder. Copyright distribution system. 7. The digital work distribution system according to claim 6, wherein the write data designated by the copyright holder designation information is a character string for identifying a copyright holder registered in the copyright holder designation information. Or, a digital work distribution system characterized by being generated from a symbol string. 8. The digital work distribution system according to claim 1, wherein the encryption means encrypts the restored object with a user's public key to create encrypted data. The digital work distribution system, wherein the decryption means decrypts the encrypted data with a user's private key to convert the restored object into plain text. 9. The digital copyrighted work distribution system according to claim 1, wherein the use condition includes a description of a period during which the user can use the use condition determining means, The encryption means has a date and time detecting means for detecting the date and time when the encrypted data is decrypted, and the time and date indicated by the date and time detected by the date and time detecting means and the period indicated by the description included in the usage condition of the encrypted data The digital copyrighted material distribution system is characterized in that it is determined whether or not the date and time is within the period. 10. A distribution center apparatus which is connected to a network by a communication means, has a memory for storing at least digitized data, and provides a digital work which is a digital work, which is an original. Processing and editing means for processing and editing data to create distribution data, and means for managing a history of the processing and editing,
Means for creating a restoration program for restoring the original data from the distribution data by referring to the edit history, and difference data creation for creating difference data that is data obtained by taking the difference between the original data and the distribution data Means, means for setting usage conditions that are conditions for using the digital work with the second device, and creation of a restoration object obtained by encapsulating the restoration program, the difference data, and the usage conditions. A distribution center device comprising means and encryption means for encrypting the restored object. 11. A user device, which is connected to a network by a communication means and uses the digital work provided via the network, for decrypting encrypted data received from the network. Means, means for determining availability based on usage conditions in the restoration object, means for executing the restoration program based on the determination result, and means for reproducing original data restored by execution of the restoration program A user device comprising: