JP2006211264A - Image reading apparatus and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reading apparatus and an image forming apparatus capable of preventing leakage of information even if an image storage means such as a hard disk in the apparatus is illegally accessed. <P>SOLUTION: In the image reading apparatus, a classified document is treated as a document provided with public key information in a mode in which the information cannot be easily visually recognized. When the classified document is read with an image reader 2, the public key information included in the classified document is extracted by an information extractor 22. Using the extracted public key information, the classified document is subjected to encryption processing in an encryption processor 23. As a result, the image data of the classified document to be outputted from the reader 2 are data subjected to the encryption processing, the image data are encrypted data even if the data are stored in a memory 5, and the read image data cannot be understood even if the memory 5 is illegally accessed. Thus, the leakage of the information can be prevented even if the storage means such as the hard disk in the apparatus is illegally accessed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image reading apparatus represented by a scanner and an image forming apparatus such as a copying machine, a facsimile machine, and a printer, and more particularly to a function for preventing unauthorized reading and copying of confidential documents.

In recent years, there has been a strong demand for a function having the ability to regulate illegal copying of a document that is prohibited from being copied or read. In particular, leakage of confidential information due to illegal copying / reading of confidential documents in companies, etc. is a major problem, and there is a strong demand for a technology that reliably prevents the copying / reading of such confidential documents. Yes.
For example, Japanese Patent Application Laid-Open No. 2004-274092 (Patent Document 1) proposes a technique for restricting copying by detecting a tint block embedded in an original that should be prevented from being illegally copied.

The copy-forgery-inhibited pattern is a pattern in which, for example, a warning message such as “copy prohibited” appears in the background when copying without significantly impairing the readability of the document itself. The copy-forgery-inhibited pattern is originally intended to visually notify that the copied material is a copy-prohibited material, and to be a psychological deterrent.
However, in the case of a confidential document or the like, the content is more important than the appearance of the document, and it is less effective to raise the warning message. Therefore, in Patent Document 1, a background pattern is detected and a copy-forgery-inhibited pattern indicating copy prohibition. In the case where there is, there has been proposed a configuration in which copying itself, that is, image output itself is prohibited.
JP 2004-274092 A

However, the technique disclosed in Patent Document 1 has the following problems.
When copying a confidential document in which a background pattern is embedded, image data read from the confidential document is temporarily held in an image storage unit such as a hard disk. If the stored image data includes a feature pattern such as a background pattern, image formation output (copy output) based on the image data is prohibited. However, in this case, since image data remains in the hard disk of the image forming apparatus, confidentiality may be illegally leaked by replacing the hard disk, illegally accessing the hard disk, and reading the image data. Can not prevent.

In addition, when a legitimate administrator of a confidential document needs to copy the confidential document, it cannot be copied at all.
The present invention has been made to solve the problems of the prior art, and an image reading apparatus and an image that can prevent information leakage even if an image storage means such as a hard disk in the device is illegally accessed. The main object is to provide a forming apparatus.

  Another object of the present invention is to provide an image forming apparatus in which only authorized persons can confirm the contents of confidential documents.

  According to the first aspect of the present invention, a reading unit for reading a document image as image data, and when the public key information is included in the image data read by the reading unit, the public key information is extracted. And an encryption processing means for converting the image data read by the reading means into encrypted image data based on the public key information extracted by the extracting means. An image reading apparatus.

According to a second aspect of the present invention, there is provided storage means for storing encrypted image data output from the encryption processing means of the image reading apparatus according to claim 1, and encrypted data stored in the storage means. An image forming apparatus comprising: a printing unit that forms an image based on image data, prints the image on paper, and outputs the printed image.
The invention described in claim 3 includes transmission means for transmitting the encrypted image data stored in the storage means to the external apparatus in response to a request from the external apparatus. Item 3. The image forming apparatus according to Item 2.

  According to a fourth aspect of the present invention, there is provided image forming means for performing an image forming process based on given image data in response to the given image data to be printed, and the image data to be printed. In response to the application of the public key information, the provided public key information is included in the image formed by the image forming unit in a form that is difficult to visually recognize or that does not impair the readability of the formed image. And an additional public key information adding unit.

According to the first aspect of the present invention, when the image data of the document image is read by the reading unit, it is determined whether or not the read key data includes public key information, and the public key information is included. If so, the public key information is extracted.
Then, the image data read by the reading unit is converted into encrypted image data based on the extracted public key information. The encrypted image data is derived as an output.

For this reason, by including the public key information in the confidential document in advance, even if the confidential document is read by the image reading apparatus according to the present invention, the output of the image reading apparatus is encrypted and cannot be read as it is. It becomes impossible output, and leakage of confidential document contents can be prevented.
According to the second aspect of the present invention, the image data stored in the storage unit prior to image formation by the image forming apparatus is encrypted image data. Therefore, even if the storage means is illegally accessed and the content is read, the read content is encrypted image data, and the image data cannot be restored (image formation). Data content can be prevented from leaking.

Also, even if image formation based on encrypted image data stored in the storage means is performed and the content is printed on paper, the content of the printed matter cannot be read, and leakage of confidential information is prevented. Can do.
According to a third aspect of the present invention, in the image forming apparatus according to the second aspect, the image forming apparatus further has a function of transmitting image data to the external apparatus in response to a request from the external apparatus. The image data is restored at the transmission destination and the contents cannot be read.

In this case, if the external request destination is a legitimate administrator of the confidential document or a person who is permitted to read the content of the confidential document, a secret encryption key for decrypting the encrypted image data is used. Is held. By doing so, it is possible to decrypt the encrypted image data and confirm the contents.
Therefore, only a specific person can confirm the image, and it is possible to provide an easy-to-use apparatus that can prevent secret leakage.

According to the fourth aspect of the present invention, when there is image data to be printed as a confidential document, the image data to be printed and the public key information are given, whereby the image reading apparatus and the image forming apparatus according to the present invention are provided. Thus, it is possible to provide an image forming apparatus capable of forming a document image that does not cause secret leakage.
Therefore, by replacing the existing image reading device such as a scanner or image forming device such as a copying machine with the image reading device and the image forming device according to the present invention, leakage of confidential documents is prevented, and illegal copying is effective. Can be prevented.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram showing the configuration of a multi-function copying machine according to an embodiment of the present invention.
The multi-function copying machine 1 includes an image reading unit 2, an image reproducing unit 3, and a control unit 4 for controlling the image reading unit 2 and the image reproducing unit 3. The control unit 4 includes a memory such as a hard disk. 5 is connected.

Hereinafter, the configuration and operation of the multi-function copying machine 1 according to this embodiment will be specifically described in the order of the image reproducing unit 3, the image reading unit 2, and the control unit 4.
The image reproducing unit 3 can form an image by an electrophotographic method as in a normal image forming apparatus, and can print and output the formed image on paper. In addition, it has a function of printing a confidential document (a function of outputting a confidential document with public key information added to an image).

  Therefore, the image reproducing unit 3 includes an image receiving unit 31 for receiving image data provided from a personal computer (PC) and a key information receiving unit 32 for receiving public key information provided from the personal computer. And an information addition processing unit 33 for adding the public key information received by the key information receiving unit 32 to the image received by the image receiving unit 31, and for forming and outputting an image by an electrophotographic method An image output unit 34 is provided.

FIG. 2 is a flowchart showing a processing procedure for adding public key information to image data that the control unit 4 causes the image reproduction unit 3 to perform. The addition of public key information to image data performed by the image reproduction unit 3 will be described with reference to this flowchart.
When a confidential document or the like that should be prohibited from being copied is output using the image reproducing unit 3, public key information is transmitted from the personal computer to the multi-function copying machine 1 together with the document data (image data). The public key information is key information used for an encryption method called a public key method, and a representative public key method is an RSA method. A feature of the public key method is that different keys are used for encryption and decryption, and key information called a public key is used for encryption and a secret key is used for decryption. The administrator of the confidential document creates a pair of secret key and public key in advance, transmits only the public key information, and manages the secret key so as not to leak outside.

  In the control unit 4, the image data and the public key information are transmitted from the personal computer, and the image receiving unit 31 and the key information receiving unit 32 determine whether the image data and the public key information are received in association with each other. (Step S1). When the public key information is received, the public key information is added to the image data associated with the public key information by the information addition processing unit 33 (step S2).

The public key information is added in a form that is difficult to see. This processing is performed in the information addition processing unit 33. As a method for adding information, for example, digital watermark technology can be used.
The image data to which the public key information is added is given to the image output unit 34, an image is created by the electrophotographic method, and the image is printed on paper and output (step S3). This output is a confidential document to which public key information is added.

Next, the configuration of the image reading unit 2 will be described. The image reading unit 2 can read a normal document image as well as a conventional multifunction copying machine, and can also read a confidential document to which public key information is added.
FIG. 3 is a flowchart showing a control procedure for preventing unauthorized copying.
Next, an illegal copy prevention process performed by the image reading unit 2 will be described with reference to this flowchart.

The image reading unit 2 includes an image input unit 21, an information extraction unit 22, and an encryption processing unit 23.
The image input unit 21 obtains input image data by scanning a document (step P1). The obtained input image data is sent to the information extraction unit 22. The information extraction unit 22 performs processing for extracting information added to the input image data (step P2). If the public key information is added to the input image data (YES in step P3), the public key information is extracted and sent to the subsequent encryption processing unit 23. The encryption processing unit 23 performs a process of encrypting the input image data obtained by the image input unit 21 using the public key information (step P4).

On the other hand, when the public key information is not extracted by the extraction unit 22 (in the case of image data to which nothing is added), encryption processing is not performed and input image data is output to the control unit 4.
As described above, the image reading unit 2 reads an original image to obtain image data. When the original image is a confidential document (a document with public key information added), the output image data is encrypted. The processed image data.

  The image data output from the image reading unit 2 is temporarily held in a memory 5 such as a hard disk via the control unit 4 (step P5). When the copy function is used, the image data held in the memory 5 is read out via the control unit 4 and given to the image output unit 34 of the image reproducing unit 3 so that the reproduced image is printed on paper and output ( Step P6 → P7). When the network scanner function is used, the image data read from the memory 5 is output to a transmission request destination such as a personal computer via the control unit 4 (steps P6 → P8).

In the case described above, in the case of image data to which public key information is not added (documents other than confidential documents), since the encryption processing unit 23 of the image reading unit 2 has not performed encryption, the input image data remains as it is. It is stored in the memory 5 and is output to the image reproduction unit 3 or a personal computer as required. (Processing similar to normal document processing)
On the other hand, in the case of image data of a confidential document, since public key information is added, the image data that has been encrypted by the encryption processing unit 23 is stored in the memory 5. For this reason, the image data read from the memory 5 in response to the request is encrypted image data, which is supplied to the image output unit 34 of the image reproduction unit 3 and the personal computer.

Therefore, at the time of the copy function, the print image output from the image output unit 34 is an image based on the encrypted image data, and normal output cannot be obtained, so that confidential documents can be prevented from being copied.
On the other hand, when the network scanner function is used, encrypted image data is sent to the personal computer. Since the administrator of the confidential document has a secret key for decryption, the sent image data is By performing the decoding process, a legible image can be obtained. In other words, by distributing the secret key to a person who is specifically authorized by the administrator of the confidential document, the apparatus can obtain an image that can be read only by the authorized person.

Further, since the image data stored in the memory 5 is encrypted, even when the memory 5 is illegally exchanged or the data is stolen by illegally accessing the memory 5, The stolen data cannot be reproduced in a readable manner unless the secret key is known, and the contents can be secured.
As described above, according to the multi-function copying machine according to this embodiment, public key information is added to a confidential document or the like that should be prohibited from unauthorized copying and reading, and data is obtained using the public key information when the confidential document is read. By encrypting, the security of confidential information can be enhanced and unauthorized copying can be prevented.

In addition, an administrator of a confidential document that owns a private key that is paired with a public key and a person equivalent thereto receive data encrypted using the public key and decrypt it using the private key. A readable document can be obtained.
The present invention is not limited to the embodiment described above, and various modifications can be made within the scope of the claims.

1 is a block diagram showing a configuration of a multi-function copying machine according to an embodiment of the present invention. It is a flowchart showing the process sequence for adding public key information with respect to the image data which a control part makes an image reproduction part perform. It is a flowchart showing the control procedure for unauthorized copy prevention.

Explanation of symbols

1 Multifunctional copier (multifunctional image forming device)
2 Image reading unit 3 Image playback unit 4 Control unit 5 Memory (hard disk, etc.)
DESCRIPTION OF SYMBOLS 21 Image input part 22 Information extraction part 23 Encryption processing part 31 Image reception part 32 Key information reception part 33 Information addition process part 34 Image output part

Claims (4)

Reading means for reading a document image as image data;
When public key information is included in the image data read by the reading means, an extracting means for extracting the public key information;
Encryption processing means for converting the image data read by the reading means into encrypted image data based on the public key information extracted by the extracting means;
An image reading apparatus comprising: Storage means for storing encrypted image data output from the encryption processing means of the image reading apparatus according to claim 1;
Print means for forming an image based on the encrypted image data stored in the storage means, printing it on paper, and outputting it;
An image forming apparatus comprising:   The image forming apparatus according to claim 2, further comprising a transmission unit that transmits the encrypted image data stored in the storage unit to the external device in response to a request from the external device. An image forming means for performing an image forming process based on the given image data in response to the image data to be printed;
In an image formed by the image forming means in response to the public key information being given in relation to the image data to be printed, an aspect that is difficult to visually recognize or an aspect that does not impair the readability of the formed image And public key information adding means for adding the given public key information,
An image forming apparatus comprising:

Images