JP2008271508A - Image processing apparatus, image forming apparatus, image transmitting device, image reading device, image processing system, image processing method, image processing program, and recording medium therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow an administrator to easily check whether the result of determination is appropriate or not without requiring a larger and more complex structure, in an image processing apparatus for determining whether input image data are identical with image data of a registered image or not and performing a process according to the result of the determination. <P>SOLUTION: Input image data whose similarity to a registered image is not less than a predetermined first threshold value or compressed image data obtained by compressing the input image data are stored in an access limitation storage section to which only a specific user is accessible. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image processing apparatus, an image forming apparatus, an image transmitting apparatus, an image reading apparatus, and an image processing system that determine the degree of similarity between input image data and registered image data registered in advance and perform control according to the determination result. The present invention relates to an image processing method, an image processing program, and a recording medium thereof.

  Conventionally, input image data obtained by reading a document image with a scanner is compared with a registered image registered in advance to determine the similarity between the two, and processing on the input image data based on the determination result (for example, Technology for controlling copying, transmission, editing, etc. is used.

  As a method for determining the similarity, for example, a keyword is extracted from an image using an OCR (Optical Character Reader) or the like and matching is performed based on the keyword, or the target image is limited to a form image having a ruled line, and matching is performed based on the characteristic of the ruled line. And the like (see Patent Document 1), the determination method based on the input image data and the color distribution of the registered image (see Patent Document 2), and the like. Patent Document 3 generates a descriptor that is selected so as to be invariant to distortion caused by digitization of the document from the characteristics of the input document and a difference between the input document and a matching document in the document database, A technique for matching an input document with a document in the document database by using this descriptor and a descriptor database that indicates a list of documents including a feature in which the descriptor is extracted and the descriptor is extracted is disclosed. In this technique, when the descriptor database is scanned, votes for each document in the document database are accumulated, and a document having the highest number of votes or a document whose number of votes exceeds a certain threshold value is regarded as a consistent document. Yes.

  In Patent Document 4, a plurality of feature points are extracted from a digital image, a set of local feature points is determined for each extracted feature point, and a subset of feature points is selected from each determined set Then, as an amount to characterize each selected subset, invariants for geometric transformation are obtained based on a plurality of combinations of feature points in the subset, and feature amounts are calculated by combining the obtained invariants. A technique for searching for a document / image corresponding to the digital image by voting on a document / image in a database having a calculated feature amount is disclosed.

  Further, as a technique for controlling processing on input image data in accordance with the similarity determination result, for example, input based on a pattern detected from input image data in order to deal with counterfeit bills and securities by a color image forming apparatus. It is determined whether the image data is image data of banknotes, securities, etc. (registered images). If the image data is image data of registered images, the image forming apparatus that made the copy can be identified from the output image. There are known techniques for adding a specific pattern to an image to be output to the printer, painting a copy image, or prohibiting a copy operation.

Further, in Patent Document 5, when it is determined that a specific image (or a similar image) is included in the document, a predetermined error code is displayed on the operation unit of the color copying machine, and the conveyance path of the recording paper Is disclosed, and the recording paper is discharged to a paper discharge tray having a cover lock mechanism. With this technology, when the formed image is not a specific manuscript, a service person dispatched to the customer uses a predetermined key card or password to release the lock mechanism and take out the internal recording paper. It has become.
JP-A-8-255236 (released on October 1, 1996) JP 5-110815 A (published April 30, 1993) Japanese Patent Laid-Open No. 7-282088 (released on October 27, 1995) International Publication No. 2006/092957 pamphlet (published on September 8, 2006) JP 2004-202737 A (released July 22, 2004) JP 2006-203824 A (released on August 3, 2006)

  By the way, in an image processing apparatus that determines whether input image data is image data of a registered image, an erroneous determination may occur depending on conditions at the time of reading due to limitations on image reading accuracy and the like. For this reason, for example, when it is erroneously determined that the input image data that is not the image data of the registered image is the image data of the registered image, an administrator (specific user; for example, a company) A specific person who has the authority to make a judgment about the suitability of the judgment result, such as a security officer, etc. Become.

  However, among the above-described conventional techniques, when it is determined that the input image data is the image data of the registered image, the copy image is filled, the copy operation is prohibited, or a specific pattern is added to the output image. With this technique, the input image data or the recording paper on which the image is formed according to the input image data is not stored, so that the suitability of the determination result cannot be confirmed later.

  In the technique disclosed in Patent Document 5, it is necessary to provide a paper discharge tray having a cover lock mechanism, a switching mechanism for switching a recording paper conveyance path, and the like. This will increase costs.

  If the determination result is appropriate, that is, if the input image data is registered image data that is prohibited from being copied, the recording paper, toner, ink, or image consumed when the input image data is printed Since resources such as electric power required for formation are wasted, the running cost is increased.

  Further, the technique of Patent Document 5 can be applied only to a configuration in which an image corresponding to input image data is formed on a recording sheet. For example, an apparatus that transmits image data (electronic distribution, facsimile transmission, etc.) or filings. There is also a problem that cannot be applied.

  Further, in the technique of Patent Document 5, the suitability of the determination result cannot be determined until the service person actually arrives at the customer, releases the lock mechanism, and takes out and confirms the recording paper on which the copy image is formed. For this reason, when the input image data is not the image data of the registered image, the recording paper on which the image is formed cannot be obtained until the movement and confirmation of the service person is completed, which is very inconvenient for the user. Also, it takes time for the service person to move to the place where the copying machine is installed, release the lock mechanism, and determine whether the determination result is appropriate.

  The present invention has been made in view of the above problems, and an object of the present invention is to determine whether input image data is image data of a registered image and perform processing according to the determination result. An object of the present invention is to realize an image processing apparatus in which an administrator can easily confirm the suitability of a determination result without increasing the size and complexity of the apparatus configuration.

  In order to solve the above problems, an image processing apparatus of the present invention includes an input data acquisition unit that acquires input image data, a feature amount extraction unit that extracts a feature amount of the input image data, and a feature amount of a registered image At least one of a registered image acquisition unit that acquires a feature amount of a registered image from a storage unit that stores information and an external device connected to be communicable with the feature amount of the input image data and the feature amount of the registered image An image processing apparatus comprising: a similarity calculation unit that calculates a similarity between both images; and a control unit that controls processing on the input image data according to the similarity. When the similarity calculated by the degree calculation unit is equal to or greater than a preset first threshold, the input image data or the compressed image data obtained by compressing the input image data is accessed only by a specific user. It is characterized in that is stored in the qualified storage. Note that the input data acquisition unit may acquire input image data by reading a document with a scanner, for example, and an input created by inputting necessary items using software as a format of electronic data Image data may be acquired, input image data directly created as electronic data may be acquired, and input transmitted from a device connected to be communicable with the image processing device Image data may be acquired.

According to said structure, at least one of the memory | storage part which memorize | stored the feature-value of the registration image, and the registration-image acquisition part which acquires the feature-value of a registration image from the external apparatus connected so that communication was possible is provided. Then, the feature amount extraction unit extracts the feature amount of the input image data, the similarity calculation unit extracts the feature amount of the registered image read from the storage unit, or the feature amount of the registered image acquired by the registered image acquisition unit, and the feature amount The feature amount of the input image data extracted by the extraction unit is compared, and the similarity between both images is calculated. Then, when the similarity calculated by the similarity calculation unit is equal to or greater than a preset first threshold, only a specific user can access the input image data or compressed image data obtained by compressing the input image data. Are stored in a proper access restriction storage unit.

  As a result, the input image data whose similarity to the registered image is equal to or greater than the first threshold or the compressed image data thereof is stored in the access restriction storage unit, so that the specific user can store the input image data stored in the access restriction storage unit or By browsing the compressed image data, the suitability of the determination result can be easily confirmed. Further, since only the control unit and the access restriction storage unit need be provided, for example, a paper discharge tray provided with a cover lock mechanism as in the technique of Patent Document 5, a switching mechanism for switching the recording paper conveyance path, and the like. There is no need to provide it. For this reason, it is possible to realize an apparatus capable of easily confirming the suitability of the determination result without enlarging the apparatus configuration, complicating the apparatus, and increasing the apparatus cost. Further, the present invention is not limited to a configuration in which an image corresponding to input image data is formed on a recording material, but can be applied to a configuration in which input image data is electronically distributed, transmitted by facsimile, or filed, for example.

  In addition, a processing input unit that receives a processing request for the input image data is provided, and the control unit has a similarity calculated by the similarity calculation unit that is equal to or higher than a second threshold that is set in advance to a value that is equal to or higher than a first threshold. In some cases, execution of processing according to the processing request for the input image data is prohibited or restricted, and the similarity calculated by the similarity calculation unit is equal to or higher than the first threshold and lower than the second threshold. May be configured to permit execution of processing according to the processing request for the input image data.

  According to said structure, execution of a process can be prohibited or restrict | limited about the input image data with high possibility of being image data of a registration image, and the security regarding a registration image can be improved.

  Note that the second threshold value may be equal to the first threshold value or a value larger than the first threshold value. When the second threshold value is larger than the first threshold value, the input image data having a similarity higher than the first threshold value and lower than the second threshold value is permitted without prohibiting or restricting execution of the process, and this input image is also permitted. The data or the compressed image data is stored in the access restriction storage unit. This suppresses the stagnation of processing due to erroneous determination that the image data is registered image although it is not image data of the registered image, and the registered image regardless of the image data of the registered image. The specific user can later view the input image data that may have been erroneously determined not to be the image data or the compressed image data, and can confirm the suitability of the determination result.

  A user information storage unit that stores user information for specifying a user who is permitted to execute the process on the input image data even when the similarity calculated by the similarity calculation unit is equal to or greater than a second threshold. The control unit receives input of user information input via the process input unit when the similarity calculated by the similarity calculation unit is equal to or greater than a second threshold, and receives the process input If the user information that matches the user information input via the user information is present in the user information stored in the user information storage unit, and if there is matching user information, The input image data or compressed image data obtained by compressing the input image data and user information are associated with each other and stored in the access restriction storage unit, and processing on the input image data is performed. It may be configured to allow the execution.

  According to said structure, even if it is a case where the similarity calculated by the similarity calculation part is more than a 2nd threshold value, the user's user who permits execution of a process by the user information input via a process input part When the information is stored in advance in the user information storage unit, the execution of the process on the input image data is permitted on condition that the input image data or the compressed image data and the user information are stored in the access restriction storage unit. To do. Thereby, even if it is determined that the image data is a registered image, it is possible to perform processing on the input image data, so that it is possible to suppress stagnation of processing due to erroneous determination. Further, when it is determined that the image data is a registered image and the execution of the process is permitted, the specific user can later store the input image data or the compressed image data in the access restriction storage unit. Since the determination result can be confirmed and the user who executed the process can be specified, the security related to the registered image can be ensured.

  In addition, a display unit for presenting information to the user is provided, and the control unit desires to execute processing on the input image data when the similarity calculated by the similarity calculation unit is equal to or greater than a second threshold. The display unit prompts the display to prompt the user to input instructions, and when the user inputs that the user wishes to execute the process via the process input unit, the display prompts the user information to be input. It is good also as a structure which a display part performs.

  According to the above configuration, when it is determined that the input image data is image data of a registered image, information prompting the user to input information regarding operations that can be selected by the user can be displayed on the display unit. Convenience can be improved.

  A log generation unit configured to generate log information related to the input image data; and the control unit associates the input image data or compressed image data obtained by compressing the input image data, user information, and a log. The access restriction storage unit may be configured to store them.

  According to the above configuration, when it is determined that the image data is a registered image and the execution of the process is permitted, in addition to the input image data or the compressed image data thereof and the user information, the input image data Is stored in the access restriction storage unit. Therefore, the specific user can confirm the suitability of the determination result and confirm log information for the input image data.

  The access restriction storage unit includes a first storage area and a second storage area, and the control unit performs processing when the similarity calculated by the similarity calculation unit is equal to or greater than a second threshold. Input image data that has not been executed or compressed image data obtained by compressing the input image data is stored in the first storage area, and input image data that has been processed or compressed image data obtained by compressing the input image data is stored in the second storage area. It is good also as a structure memorize | stored in a storage area.

  According to the above configuration, when it is determined that the image data is a registered image, the input image data that has been processed or the compressed image data thereof, and the input image data that has not been processed or the compressed image data thereof are Can be stored in different storage areas. Therefore, the specific user can quickly identify and confirm the input image data or the compressed image data that has been processed.

  In addition, the control unit adds user information to the input image data that has been processed or the compressed image data obtained by compressing the input image data and stores the user information in the access restriction storage unit, or the input image data or the input image data A configuration may be adopted in which a file name including user information is added to compressed image data obtained by compressing input image data and stored in the access restriction storage unit.

  According to said structure, the specific user can specify rapidly the user who performed the process with respect to input image data.

  Further, the control unit is a case where the similarity calculated by the similarity calculation unit is equal to or greater than a second threshold and less than a third threshold preset to a value larger than the second threshold, When user information that matches the user information input via the user information is present in the user information stored in the user information storage unit, the input image data or a compression obtained by compressing the input image data When the image data and the user information are associated and stored in the access restriction storage unit, and the execution of the process on the input image data is permitted, and the similarity calculated by the similarity calculation unit is equal to or greater than the third threshold value Alternatively, the configuration may be such that execution of processing on the input image data is prohibited.

  According to the above configuration, even when it is determined that the image data is a registered image, if the similarity calculated by the similarity calculation unit is greater than or equal to the second threshold and less than the third threshold, the input image Since processing can be performed on data, stagnation of processing due to erroneous determination can be suppressed. Further, when it is determined that the image data is a registered image and the execution of the process is permitted, the specific user can later store the input image data or the compressed image data in the access restriction storage unit. Since the determination result can be confirmed and the user who executed the process can be specified, the security related to the registered image can be ensured. Further, when the similarity calculated by the similarity calculation unit is equal to or greater than the third threshold value, there is a high possibility that it is not an erroneous determination (the determination that the image data of the registered image is appropriate is likely to be appropriate). Therefore, the processing for the input image data is prohibited. Thereby, it can prevent that a process is performed with respect to a registration image.

  An encryption unit configured to generate encrypted image data obtained by encrypting the input image data or the compressed image data; and the control unit includes a first similarity level calculated in advance by the similarity level calculation unit. The encrypted image data may be stored in the access restriction storage unit when it is equal to or greater than the threshold value.

  According to the above configuration, since the input image data or the compressed image data is encrypted and stored, the security related to the input image data can be improved.

  Further, it may be configured to include an encryption key storage unit that stores encryption key information for decrypting the encrypted image data in association with the encrypted image data.

  According to the above configuration, the encrypted image data can be appropriately decrypted as necessary.

  In addition, the image processing apparatus includes a communication unit that transmits image data to an external device, and the control unit responds to the encrypted image data from the external device after transmitting the encrypted image data from the communication unit to the external device. A configuration may be adopted in which an encryption key corresponding to the encrypted image data is transmitted from the communication means to the external device when an encryption key transmission request is made.

  According to the above configuration, the time when the encrypted image data is transmitted can be different from the time when the encryption key is transmitted. Therefore, the risk of illegally leaking the input image data in the communication path is reduced, and the input image Data security can be further enhanced.

  An image forming apparatus of the present invention includes any one of the above-described image processing apparatuses and an image output unit that forms an image corresponding to input image data on a recording material. An image transmission apparatus according to the present invention includes any one of the above-described image processing apparatuses and a transmission apparatus that transmits input image data to another apparatus that is communicably connected. The image reading apparatus of the present invention includes an image input apparatus that reads an original image and acquires input image data, and any one of the image processing apparatuses described above.

  According to the image forming apparatus, the image transmitting apparatus, and the image reading apparatus described above, the input image data or the compressed image data whose similarity to the registered image is equal to or higher than the first threshold value is stored in the access restriction storage unit. Can easily check the suitability of the determination result by browsing the input image data or the compressed image data stored in the access restriction storage unit.

  The image processing method of the present invention includes an input data acquisition step for acquiring input image data, a feature amount extraction step for extracting feature amounts of input image data, a registration data acquisition step for acquiring feature amounts of registered images, and an input An image processing method comprising: a similarity calculation step of calculating a similarity between both images by comparing a feature amount of image data with a feature amount of a registered image, and controlling processing on the input image data according to the similarity And a determination step of determining whether the similarity calculated in the similarity calculation step is equal to or higher than a first threshold set in advance, and the similarity is equal to or higher than a first threshold in the determination step. A storage step of storing the input image data or compressed image data obtained by compressing the input image data in an access restriction storage unit accessible only by a specific user when the determination is made. There.

  According to the above method, the feature amount of the input image data acquired in the input data acquisition step is extracted in the feature amount extraction step, and the feature amount of the registered image is acquired in the registration data acquisition step. Further, in the similarity calculation step, the feature amount of the input image data is compared with the feature amount of the registered image, and the similarity of both images is calculated. In the determination step, it is determined whether or not the similarity calculated in the similarity calculation step is greater than or equal to a preset first threshold value, and it is determined in the determination step that the similarity is greater than or equal to the first threshold value. In the storage step, the input image data or the compressed image data obtained by compressing the input image data is stored in an access restriction storage unit accessible only by a specific user.

  As a result, the input image data whose similarity to the registered image is equal to or higher than the first threshold value or the compressed image data thereof is stored in the access restriction storage unit, so that the specific user can store the input image data stored in the access restriction storage unit or By browsing the compressed image data, the suitability of the determination result can be easily confirmed.

  In order to solve the above problems, an image processing system of the present invention includes an image processing device and a server device that is communicably connected to the image processing device, and acquires input image data. A feature amount extraction unit that extracts the feature amount of the input image data, a storage unit that stores the feature amount of the registered image, and compares the feature amount of the input image data with the feature amount of the registered image. A similarity calculation unit that calculates a similarity, a control unit that controls processing for the input image data according to the similarity, and an access restriction storage unit that can be accessed only by a specific user include the image processing apparatus and the The image processing system is provided in a distributed manner with a server device, and the control unit is configured to input the input image when the similarity calculated by the similarity calculation unit is equal to or greater than a first threshold set in advance. The compressed image data obtained by compressing the over data or the input image data, is characterized in that is stored in the access limitation storage section.

  According to the above configuration, the input image data whose similarity to the registered image is equal to or higher than the first threshold or the compressed image data thereof is stored in the access restriction storage unit, so that the specific user is stored in the access restriction storage unit By browsing the input image data or the compressed image data, the suitability of the determination result can be easily confirmed. Further, since only the control unit and the access restriction storage unit need be provided, for example, a paper discharge tray provided with a cover lock mechanism as in the technique of Patent Document 5, a switching mechanism for switching the recording paper conveyance path, and the like. There is no need to provide it. For this reason, the apparatus which can confirm the suitability of a determination result easily can be implement | achieved, without enlarging an apparatus structure, complexity, an increase in apparatus cost, etc. Further, the present invention is not limited to a configuration in which an image corresponding to input image data is formed on a recording material, but can be applied to a configuration in which input image data is electronically distributed, transmitted by facsimile, or filed, for example.

  An encryption unit configured to generate encrypted image data obtained by encrypting the input image data or the compressed image data; and the control unit includes a first similarity level calculated in advance by the similarity level calculation unit. The encrypted image data may be stored in the access restriction storage unit when it is equal to or greater than the threshold value.

  According to the above configuration, since the input image data or the compressed image data is encrypted and stored, the security related to the input image data can be improved.

  Further, it may be configured to include an encryption key storage unit that stores encryption key information for decrypting the encrypted image data in association with the encrypted image data.

  According to the above configuration, the encrypted image data can be appropriately decrypted as necessary.

  In addition, the control unit causes the encrypted image data to be transmitted from the device provided with the access restriction storage unit to the other device, and then the encrypted image data from the other device. The encryption key corresponding to the encrypted image data may be transmitted to the external device when there is a transmission request for the encryption key corresponding to.

  According to the above configuration, the time when the encrypted image data is transmitted can be different from the time when the encryption key is transmitted. Therefore, the risk of illegally leaking the input image data in the communication path is reduced, and the input image Data security can be further enhanced.

  The image processing apparatus may be realized by a computer. In this case, an image processing program for causing the image processing apparatus to be realized by the computer by causing the computer to operate as the respective units, and the program are recorded. Computer-readable recording media are also included in the scope of the present invention.

  As described above, in the image processing apparatus of the present invention, when the control unit calculates the input image data or the input image when the similarity calculated by the similarity calculation unit is equal to or more than a preset first threshold value. The compressed image data obtained by compressing the data is stored in an access restriction storage unit accessible only by a specific user.

  Therefore, the appropriateness of the determination result can be easily confirmed by the specific user browsing the input image data or the compressed image data stored in the access restriction storage unit. In addition, since it is only necessary to provide the control unit and the access restriction storage unit, it is possible to easily confirm the suitability of the determination result without enlarging the apparatus configuration, complicating the apparatus, and increasing the apparatus cost. Can be realized.

Embodiment 1
An embodiment of the present invention will be described. In the present embodiment, an example in the case where the present invention is applied to a digital color multifunction peripheral (MFP) will be described.

(1-1. Configuration of Digital Color Multifunction Machine 1)
FIG. 2 is a block diagram showing a schematic configuration of a digital color multifunction peripheral (image processing apparatus, image forming apparatus, image reading apparatus) 1 according to the present embodiment. The digital color multifunction peripheral 1 has a copy function, a printer function, a facsimile transmission function, a scanner function, a scan to e-mail function, and the like.

  As shown in FIG. 2, the digital color MFP 1 includes a color image input device 2, a color image processing device 3, a color image output device 4, a communication device 5, and an operation panel 6.

  The color image input device (image reading device) 2 is composed of a scanner unit (not shown) having a device that converts optical information into an electrical signal, such as a CCD (Charge Coupled Device), for example, and a reflected light image from a document. Are output to the color image processing apparatus 3 as analog signals of RGB (R: red, G: green, B: blue).

  The color image processing apparatus 3 includes an A / D conversion unit 11, a shading correction unit 12, a document matching processing unit 13, an input tone correction unit 14, a region separation processing unit 15, a color correction unit 16, and a black generation and under color removal unit 17. A spatial filter processing unit 18, an output tone correction unit 19, and a tone reproduction processing unit 20. An analog signal output from the color image input device 2 to the color image processing device 3 is converted into an A / D conversion unit 11, a shading correction unit 12, a document matching processing unit 13, and an input tone correction unit in the color image processing device 3. 14, the region separation processing unit 15, the color correction unit 16, the black generation and under color removal unit 17, the spatial filter processing unit 18, the output gradation correction unit 19, and the gradation reproduction processing unit 20 are sent in this order, and CMYK digital color The signal is output to the color image output device 4 as a signal.

  The A / D (analog / digital) converter 11 converts RGB analog signals into digital signals.

  The shading correction unit 12 performs a process for removing various distortions generated in the illumination system, the imaging system, and the imaging system of the color image input apparatus 2 on the digital RGB signal sent from the A / D conversion unit 11. Is. Further, the shading correction unit 12 performs a process of converting color balance adjustment and a signal such as a density signal that can be easily handled by the image processing system employed in the color image processing apparatus 3.

  The document collation processing unit 13 determines the similarity between the input image data and the registered image ((similarity / no similarity)). The document collation processing unit 13 directly inputs the input RGB signal to the subsequent input. The data is output to the gradation correction unit 14. The details of the document collation processing unit 13 will be described later.

  The input tone correction unit 14 performs image quality adjustment processing such as removal of background color (background color density component: background density) and contrast on the RGB signal from which various distortions have been removed by the shading correction unit.

  The region separation processing unit 15 separates each pixel in the input image into one of a character region, a halftone dot region, and a photo region from the RGB signal. Based on the separation result, the region separation processing unit 15 generates a region identification signal indicating which region the pixel belongs to, the color correction unit 16, the black generation and under color removal unit 17, the spatial filter processing unit 18, and the gradation reproduction. The output signal is output to the processing unit 20, and the input signal output from the input tone correction unit 14 is output to the subsequent color correction unit 16 as it is.

  The color correction unit 16 performs a process of removing color turbidity based on spectral characteristics of CMY (C: cyan, M: magenta, Y: yellow) color materials including unnecessary absorption components in order to realize faithful color reproduction. Is.

  The black generation and under color removal unit 17 generates black (K) signals from the CMY three-color signals after color correction, and subtracts the K signals obtained by black generation from the original CMY signals to generate new CMY signals. The process to generate is performed. As a result, the CMY three-color signal is converted into a CMYK four-color signal.

  The spatial filter processing unit 18 performs spatial filter processing using a digital filter on the image data of the CMYK signal input from the black generation and under color removal unit 17 to correct the spatial frequency characteristics. As a result, blurring of the output image and deterioration of graininess can be reduced. Similar to the spatial filter processing unit 18, the gradation reproduction processing unit 20 also performs predetermined processing on the image data of the CMYK signal based on the region identification signal.

  For example, the region separated into characters by the region separation processing unit 15 has a high frequency enhancement amount in the sharp enhancement processing in the spatial filter processing by the spatial filter processing unit 18 in order to improve the reproducibility of black characters or color characters. Increased. At the same time, the tone reproduction processing unit 20 selects binarization or multi-value processing on a high-resolution screen suitable for high-frequency reproduction.

  Further, with respect to the region separated into halftone dot regions by the region separation processing unit 15, the spatial filter processing unit 18 performs low-pass filter processing for removing the input halftone component. The output tone correction unit 19 performs an output tone correction process for converting a signal such as a density signal into a halftone dot area ratio that is a characteristic value of the color image output device 4. Then, gradation reproduction processing (halftone generation) is performed so that the image is finally separated into pixels and each gradation is reproduced. For the region separated into photographs by the region separation processing unit 15, binarization or multi-value processing is performed on the screen with an emphasis on gradation reproducibility.

  The image data subjected to the above-described processes is temporarily stored in a storage device (not shown), read out at a predetermined timing, and input to the color image output device 4.

  The color image output device 4 outputs the image data input from the color image processing device 3 onto a recording material (for example, paper). The configuration of the color image output device 4 is not particularly limited, and for example, a color image output device using an electrophotographic method or an inkjet method can be used.

  The communication device 5 is composed of a modem or a network card, for example. The communication device 5 performs data communication with other devices (for example, personal computers, server devices, other digital multifunction peripherals, facsimile devices, etc.) connected to the network via a network card, a LAN cable, or the like.

  When the image data is transmitted, the communication device 5 performs the transmission procedure with the other party and secures a state in which the image data can be transmitted. Then, the communication device 5 compresses the image data (image data read by the scanner) in a predetermined format. ) Is read from the memory, and necessary processing such as changing the compression format is performed, and then sequentially transmitted to the other party via the communication line.

  Further, when receiving the image data, the communication device 5 performs a communication procedure and receives the image data transmitted from the other party and inputs it to the color image processing device 3. The received image data is subjected to predetermined processing such as expansion processing, rotation processing, resolution conversion processing, output gradation correction, gradation reproduction processing, and the like by the color image processing apparatus 3 and is output by the color image output apparatus 4. The received image data may be stored in a storage device (not shown), and the color image processing device 3 may read it out as necessary to perform the predetermined processing.

  The operation panel 6 includes, for example, a display unit such as a liquid crystal display and setting buttons (none of which are shown), and information corresponding to an instruction from a main control unit (not shown) of the digital color multifunction peripheral 1 is described above. While displaying on a display part, the information input from a user via the said setting button is transmitted to the said main control part. The user inputs a processing request (for example, processing mode (copying, printing, transmission, editing, etc.), number of copies (number of copies, number of copies), destination of input image data, etc.) for the input image data via the operation panel 6. can do. The main control unit includes, for example, a CPU (Central Processing Unit) and the like, and is based on programs and various data stored in a ROM (not shown) and the like, information input from the operation panel 6, and the like. To control the operation.

(1-2. Configuration of Document Collation Processing Unit)
Next, details of the document matching processing unit 13 will be described. The document matching processing unit 13 according to the present embodiment extracts a plurality of feature points from input image data, determines a set of local feature points for each extracted feature point, and features points from the determined sets. As a quantity that characterizes each selected subset, an invariant for geometric transformation is obtained based on a plurality of combinations of feature points in the subset, and the obtained invariants are combined. By calculating a hash value and voting for a registered image corresponding to the calculated hash value, a search for a registered image similar to the input image data and a determination process of similarity to the registered image (judgment of similarity / no similarity) I do.

  FIG. 1 is a block diagram illustrating a schematic configuration of the document matching processing unit 13. As shown in this figure, the document matching processing unit 13 includes a feature point calculation unit 31, a feature amount calculation unit 32, a voting processing unit 33, a similarity determination processing unit 34, a compression / decompression processing unit 35, a registration processing unit 37, A control unit 7 and a memory 8 are provided.

  The control unit 7 controls the operation of each unit of the document collation processing unit 13. The control unit 7 may be provided in a main control unit for controlling the operation of each unit of the digital color multifunction peripheral 1, and is provided separately from the main control unit. It may control the operation of the processing unit 13.

  When it is determined that there is no similarity (the input image data is not the image data of the registered image) as a result of the similarity determination process by the document collation processing unit 13, the control unit 7 permits the process on the input image data, and the similarity If it is determined that the input image data is the image data of the registered image, the input image data (or compressed image data obtained by compressing the input image data) is stored in the administrator folder 8A provided in the memory 8. It is like that. Further, when it is determined that there is similarity, the control unit 7 inquires of the user whether or not to continue image processing (copying, printing, transmission, editing, etc.), and when continuation of image processing is requested. Authenticates whether or not this user is a user who should be allowed to continue image processing. If the authentication is successful, user information and log (operation record information; for example, input document data ID and processing request are input. User ID, date and time when the processing request was input, processing request content (processing mode, number of processing, transmission destination, editing content, etc.), similarity, user information (user ID, password, etc.) Execution of image processing is permitted after being stored in the administrator folder 8A. However, the present invention is not limited to this. For example, when it is determined that there is similarity, processing on the input image data is prohibited, and the input image data (or compressed image data obtained by compressing the input image data) is provided in the memory 8. May be stored in the administrator folder 8A.

  The memory 8 stores various data used for processing of each unit of the document collation processing unit 13, processing results, and the like. In addition, the memory 8 stores an administrator (a person registered in advance who has the authority to permit processing of input image data when the determination of whether or not the determination result is appropriate and the determination of similarity is an erroneous determination. Administrator folder 8A, which is a folder (storage area) that can be browsed and edited only by a security officer at a company, a store, etc. (however, the control unit 7 can refer to information in the administrator folder 8A if necessary) It has.

  In the administrator folder 8A, an administrator information storage unit 101, a user information storage unit 102, a hash table 103, an image data storage unit (similar image data storage unit) 104, and the like are provided.

  The administrator information storage unit 101 stores information for specifying an administrator who is permitted to view and edit the administrator folder 8A. When browsing or editing of the administrator folder 8A is requested, the control unit 7 performs an authentication process based on the administrator information storage unit 101 and determines whether to permit browsing or editing. . Note that the administrator authentication processing method is not particularly limited, and various conventionally known authentication processing methods can be used, for example. In this embodiment, the administrator transmits information necessary for authentication to the digital color multifunction device 1 from an external device (computer, server device, etc.) that is communicably connected to the digital color multifunction device 1. Although the authentication process is performed, the present invention is not limited to this. For example, the authentication process may be performed via the operation panel 6 of the digital color multifunction peripheral 1.

  The user information storage unit 102 permits continuation when it is determined that there is similarity (the input image data is image data of a registered image) and the user desires to continue image processing on the input image data. When the user information of the user is stored, and the user desires to continue the image processing, the control unit 7 refers to the user information stored in the user information storage unit 102 and performs the user authentication process. It has become. The method of user authentication processing is not particularly limited, and various conventionally known authentication processing methods can be used, for example.

  The hash table 103 is a table in which the feature amount of the registered image is stored. Details of the hash table 103 will be described later.

  The image data storage unit 104 determines that there is similarity (the input image data is image data of a registered image), and the user desires to continue image processing on the input image data, and the control unit 7 performs user authentication. When the continuation of the image processing is permitted as a result of the processing, the storage unit stores the input image data (or compressed image data obtained by compressing the input image data).

  The feature point calculation unit 31 extracts a connected part of a character string or a ruled line, and calculates the center of gravity of the connected part as a feature point. However, the configuration of the feature point calculation unit 31 is not limited to this. For example, the feature points may be calculated by various conventionally known methods.

  FIG. 3 is a block diagram illustrating a schematic configuration of the feature point calculation unit 31. As shown in this figure, the feature point calculation unit 31 includes an achromatic processing unit 41, a resolution conversion unit 42, an MTF processing unit 43, a binarization processing unit 44, and a centroid calculation unit 45.

  When the image data (RGB signal) input from the shading correction unit 12 is a color image, the achromatic processing unit 41 is achromatic and converts the image data into a lightness signal or a luminance signal. .

  For example, the achromatic processing unit 41 converts the RGB signal into the luminance signal Y by the following equation (1).

Yi = 0.30Ri + 0.59Gi + 0.11Bi (1)
Here, Y is a luminance signal of each pixel, R, G, and B are each color component in the RGB signal of each pixel, and the subscript i is a value assigned to each pixel (i is an integer of 1 or more). It is.

Alternatively, the RGB signal may be converted into a CIE 1976 L ^* a ^* b ^* signal (CIE: Commission International de l'Eclairage, L ^* : brightness, a ^* , b ^* : chromaticity).

  The resolution conversion unit 42 performs a scaling process on the input image data. For example, when the input image data is optically scaled by the color image input device 2, the resolution conversion unit 42 scales the input image data again so that the predetermined resolution is obtained. Further, the resolution conversion unit 42 may perform resolution conversion for lowering the resolution than the resolution read at the same magnification in the color image input device 2 in order to reduce the processing amount in each processing unit in the subsequent stage. (For example, image data read at 600 dpi (dot per inch) is converted to 300 dpi).

  An MTF (modulation transfer function) processing unit 43 is used to absorb (adjust) that the spatial frequency characteristics of the color image input device 2 are different for each model. In the image signal output by the CCD, MTF degradation occurs due to optical components such as lenses and mirrors, aperture aperture of the light receiving surface of the CCD, transfer efficiency and afterimages, integration effects due to physical scanning, and uneven operation. ing. Due to the deterioration of the MTF, the read image is blurred. The MTF processing unit 43 performs a process of repairing the blur caused by the deterioration of the MTF by performing an appropriate filter process (enhancement process). Further, it is also used to suppress high-frequency components that are not necessary for the feature point extraction processing in the latter-stage gravity center calculation unit 45. That is, enhancement and smoothing processing is performed using a mixing filter (not shown). FIG. 4 shows an example of the filter coefficient in this mixed filter.

  The binarization processing unit 44 binarizes the image data by comparing the achromatic image data (brightness value (brightness signal) or brightness value (brightness signal)) with a preset threshold value. .

  The center-of-gravity calculation unit 45 performs labeling (labeling processing) on each pixel based on the image data binarized by the binarization processing unit 44 (for example, represented by “1” and “0”). I do. Then, a connected area where pixels with the same label are connected is specified, and the center of gravity of the specified connected area is extracted as a feature point. Further, the extracted feature points are output to the feature amount calculation unit 32. FIG. 5 is an explanatory diagram showing an example of the connected area extracted from the input image data and the center of gravity of the connected area, and shows the connected area and the center of gravity corresponding to the character string “A”. FIG. 6 is an explanatory diagram showing an example of each center of gravity (feature point) of a plurality of connected regions extracted from a character string included in input image data. The feature points can be represented by coordinate values (x coordinate, y coordinate) in the binary image.

  The feature amount calculation unit 32 includes a feature point extraction unit 32a, an invariant calculation unit 32b, and a hash value calculation unit 32c. The feature point calculated by the feature point calculation unit 31 is used to rotate and parallelize a document image. A feature amount (hash value and / or invariant) that is an invariable amount with respect to geometric deformation such as movement, enlargement, reduction, and parallel movement is calculated.

  As shown in FIG. 7, the feature point extraction unit 32a sets one feature point as a target feature point, and sets a predetermined number of feature points in the vicinity of the target feature point in order from the closest distance from the target feature point (here 4 points) are extracted as peripheral feature points. In the example of FIG. 7, when the feature point a is the feature point of interest, four feature points b, c, d, and e are extracted as the peripheral feature points, and when the feature point b is the feature point of interest. Four points of feature points a, c, e, and f are extracted as peripheral feature points.

  Further, the feature point extraction unit 32a extracts a combination of three points that can be selected from the four peripheral feature points extracted as described above. For example, as shown in FIGS. 8A to 8C, when the feature point a shown in FIG. 7 is the target feature point, three of the peripheral feature points b, c, d, and e Combinations, that is, combinations of peripheral feature points b, c, d, peripheral feature points b, c, e, and peripheral feature points b, d, e are extracted.

  Next, the invariant calculation unit 32b calculates an invariant (one of feature quantities) Hij with respect to geometric deformation for each extracted combination. Here, i is a number indicating the feature point of interest (i is an integer equal to or greater than 1), and j is a number indicating a combination of three peripheral feature points (j is an integer equal to or greater than 1). In the present embodiment, the ratio of two of the lengths of the line segments connecting the peripheral feature points is set as the invariant Hij. The length of the line segment may be calculated based on the coordinate value of each peripheral feature point. For example, in the example of FIG. 8A, if the length of the line segment connecting the feature point c and the feature point d is A11 and the length of the line segment connecting the feature point c and the feature point b is B11, The variable H11 is H11 = A11 / B11. In the example of FIG. 8B, if the length of the line segment connecting the feature point c and the feature point b is A12 and the length of the line segment connecting the feature point b and the feature point e is B12, The variable H12 is H12 = A12 / B12. In the example of FIG. 8C, if the length of the line segment connecting the feature point d and the feature point b is A13 and the length of the line segment connecting the feature point b and the feature point e is B13, The variable H13 is H13 = A13 / B13. In this way, invariants H11, H12, and H13 are calculated in the examples of FIGS. 8 (a) to 8 (c). In the above example, the line segment connecting the peripheral feature point located on the left side in the horizontal direction and the peripheral feature point located in the center in the horizontal direction is Aij, and the peripheral feature point located in the center in the horizontal direction is located on the right side in the horizontal direction. The line segment connecting the peripheral feature points is Bij. However, the present invention is not limited to this, and the line segment used for calculating the invariant Hij may be selected by an arbitrary method.

Next, the hash value calculation unit 32c calculates a remainder value of (Hi1 × 10 ² + Hi2 × 10 ¹ + Hi3 × 10 ⁰ ) / D as a hash value (one of feature quantities) Hi and stores it in the memory 8. . Note that D is a constant set in advance according to how much the range of values that the remainder can take is set.

  Note that the method for calculating the invariant Hij is not particularly limited. For example, the cross ratio of five points in the vicinity of the feature point of interest, or the double ratio of five points extracted from the neighboring n points (n is an integer of n ≧ 5). The value calculated based on the arrangement of m points extracted from n points in the vicinity (m is an integer of m <n and m ≧ 5) and the cross ratio of the five points extracted from m points, etc. The invariant Hij may be used. The cross ratio is a value obtained from four points on a straight line or five points on a plane, and is known as an invariant with respect to projective deformation which is a kind of geometric transformation.

  Also, the formula for calculating the hash value Hi is not limited to the above formula (2), and other hash functions (for example, any one of the hash functions described in Patent Document 4) may be used. Good.

  Further, each part of the feature quantity calculation unit 32, after completing the extraction of the peripheral feature points for one target feature point and the calculation of the hash value Hi, changes the target feature point to another feature point, A hash value is calculated, and hash values for all feature points are calculated.

  In the example of FIG. 7, when the extraction of the peripheral feature point and the hash value when the feature point a is the target feature point is finished, the extraction of the peripheral feature point and the hash value when the feature point b is the target feature point is completed. I do. In the example of FIG. 7, when the feature point b is set as the feature point of interest, four feature points a, c, e, and f are extracted as the peripheral feature points. Then, as shown in FIGS. 9A to 9C, a combination of three points selected from these peripheral feature points a, c, e, and f (peripheral feature points a, e, f, and peripheral points) Feature points c, e, f, peripheral feature points a, c, f) are extracted, and a hash value Hi is calculated for each combination and stored in the memory 8. Then, this process is repeated for each feature point, and a hash value when each feature point is a feature point of interest is obtained and stored in the memory 8.

  Note that the invariant calculation method when the feature point a is the feature point of interest is not limited to the above method. For example, as shown in FIGS. 20A to 20D, when the feature point a shown in FIG. 7 is the feature point of interest, three of the peripheral feature points b, c, d, and e are selected. Combinations, that is, peripheral feature points b, c, d, peripheral feature points b, c, e, peripheral feature points b, d, e, peripheral feature points c, d, e are extracted, and each extracted combination , An invariant (one of feature quantities) Hij with respect to geometric deformation may be calculated.

  Further, when the feature point b shown in FIG. 7 is set as a feature point of interest, as shown in FIGS. 21A to 21D, four peripheral feature points of feature points a, c, e, and f are used. A combination of three points (peripheral feature points a, e, f, peripheral feature points a, c, e, peripheral feature points a, f, c, peripheral feature points e, f, c) from You may make it calculate the invariant Hij with respect to geometric deformation about each combination. In this case, the remainder of (Hi1 × 103 + Hi2 × 102 + Hi3 × 101 + Hi4 × 100) / D may be calculated as a hash value and stored in the memory 8.

  In the above example, the line segment connecting the peripheral feature point closest to the target feature point and the second closest peripheral feature point is Aij, and the peripheral feature point closest to the target feature point and the third closest peripheral feature point are The line segment connecting the two is connected to Bij. However, the present invention is not limited to this, and the line segment used for calculating the invariant Hij may be selected by an arbitrary method such as selecting based on the length of the line segment connecting the neighboring feature points. That's fine.

  Note that, when performing registration processing for registering input image data as a registered image, the feature amount calculation unit 32 performs registration processing for hash values (feature amounts) for each feature point of the input image data calculated as described above. Send to part 37.

  The registration processing unit 37 sequentially registers a hash value for each feature point calculated by the feature amount calculation unit 32 and an index (document ID) representing a document (input image data) in the hash table 103 provided in the memory 8. (See FIG. 10A). If the hash value is already registered, the document ID is registered in association with the hash value. Document IDs are sequentially assigned numbers without duplication. When the number of documents registered in the hash table 103 exceeds a predetermined value (for example, 80% of the number of documents that can be registered), the old document ID may be searched and sequentially deleted. . The deleted document ID may be used again as the document ID of new input image data. Further, when the calculated hash values are the same value (H1 = H5 in the example of FIG. 10B), these may be combined and registered in the hash table 103.

  In addition, when performing a determination process (similarity determination process) on whether or not the input image data is image data of a registered image that has already been registered, the feature amount calculation unit 32 calculates the input image calculated as described above. A hash value for each feature point of the data is sent to the voting processing unit 33.

  The voting processing unit 33 compares the hash value of each feature point calculated from the input image data with the hash value registered in the hash table 103, and votes for registered images having the same hash value. In other words, for each registered image, the number of times the same hash value as the hash value of the registered image is calculated from the input image data is counted, and the count value is stored in the memory 8. FIG. 11 is a graph showing an example of the number of votes for registered images ID1, ID2, and ID3.

  The similarity determination processing unit 34 reads the voting result (the index of each registered image and the number of votes for each registered image; similarity) of the voting processing unit 33 from the memory 8 and obtains the maximum number of votes and the maximum number of votes obtained. Extract image index. Then, the extracted maximum number of votes is compared with a predetermined threshold (second threshold) TH2 to determine similarity (whether or not the input image data is image data of a registered image), and the determination result is shown. A determination signal is sent to the control unit 7. That is, when the maximum number of votes is greater than or equal to a predetermined threshold TH2, it is determined that there is a similarity (the input image data is image data of a registered image). No determination is made (the input image data is not image data of a registered image) ”.

  Alternatively, the similarity determination processing unit 34 calculates the similarity by dividing and normalizing the number of votes obtained for each registered image by the total number of votes (the total number of feature points extracted from the input image data). And the threshold value TH2 (for example, 80% of the total number of votes) may be compared to determine the similarity.

  In addition, the similarity determination processing unit 34 normalizes the number of votes obtained for each registered image by dividing by the number of registered hash values (maximum registered number) for the registered image having the largest number of registered hash values. The degree of similarity may be determined by calculating the degree and comparing the degree of similarity with a predetermined threshold TH2 (for example, 80% of the total number of votes). That is, if the calculated similarity is equal to or greater than the threshold value TH2, it is determined that “there is similarity”, and if it is less than the threshold value TH2, it is determined that “there is no similarity”. In this case, the total number of hash values extracted from the input image data may be larger than the maximum registered number (particularly when at least a part of the original and / or registered image has a handwritten part). The calculated value of similarity may exceed 100%.

  Further, the threshold value TH2 for determining similarity may be constant for each registered image, or may be set for each registered image according to the importance of each registered image. The importance of the registered image depends on the registered image, for example, the importance is maximized for banknotes, securities, confidential documents, confidential documents, etc., and the importance is lower for banknotes, etc. May be set step by step. In this case, a weighting coefficient corresponding to the importance of the registered image is stored in the memory 8 in association with the index of the registered image, and the similarity determination processing unit 34 corresponds to the registered image that has obtained the maximum number of votes. The similarity may be determined using the threshold value TH2.

  Further, when determining the similarity, the threshold value TH2 is kept constant, while the similarity is determined by multiplying the number of votes for each registered image (the number of votes of each registered image) by the weighting coefficient of each registered image. Good. In this case, a weighting coefficient corresponding to the importance of each registered image is stored in the memory 8 in association with the index of each registered image, and the similarity determination processing unit 34 determines the number of registered images for each registered image. The number of corrected votes multiplied by the weighting coefficient is calculated, and the similarity may be determined based on the number of corrected votes. For example, the maximum corrected number of votes may be compared with the threshold TH2, or the maximum corrected number of votes normalized with the total number of votes may be compared with the threshold TH2, and the maximum corrected number of votes is normalized with the maximum number of registrations. This may be compared with the threshold value TH2. In this case, for example, the weighting factor may be set to a value larger than 1, and to a larger value as the importance of the registered image becomes higher.

  In this embodiment, one hash value is calculated for one feature point (attention feature point). However, the present invention is not limited to this, and a plurality of one feature point (attention feature point) may be calculated. A hash value may be calculated. For example, 6 points are extracted as the peripheral feature points of the feature point of interest, and for each of the 6 combinations obtained by extracting 5 points from these 6 points, 3 points are extracted from 5 points to obtain an invariant and a hash value is calculated. You may use the method to do. In this case, six hash values are calculated for one feature point.

  The compression / decompression processing unit 35 performs processing for compressing input image data to generate compressed image data, and processing for decompressing compressed image data and returning it to input image data. The compression method is not particularly limited. For example, JPEG (Joint Photographic Experts Group), TIFF (Tagged Image File Format), or the like can be used.

(1-3. Processing in the digital color multifunction peripheral 1)
Next, processing in the digital color multifunction peripheral 1 will be described with reference to the flowchart shown in FIG. In the following description, it is assumed that administrator information and user information are registered in advance in the administrator information storage unit 101 and the user information storage unit 102. When it is desired to add or edit these pieces of information, the administrator may perform authentication processing, access the administrator folder 8A, and appropriately perform addition or editing processing. The user information storage unit 102 stores in advance a set value of the number of times K (for example, K = 5) for accepting re-input of user information when the authentication process for the user information input by the user has failed. It shall be.

  First, when receiving an instruction input (image processing request) from the user via the operation panel 6 or the communication device 5, the control unit 7 initializes the number of times Cp of user information to be stored in the memory 8 (Cp = 0). (S1).

  Next, the control unit 7 acquires input image data (S2). For example, input image data may be acquired by reading a document image with the color image input device 2, or input image data may be acquired from an external device by the communication device 5, and is provided in the digital color multifunction peripheral 1. Input image data may be read and acquired from various recording media via a card reader (not shown) or the like.

  Next, the control unit 7 controls each part of the document matching processing unit 13 to perform a feature point calculation process (S3), a feature amount calculation process (S4), a voting process (S5), and a similarity determination process (S6). Make it.

  If it is determined that there is no similarity as a result of the similarity determination process, the control unit 7 permits image processing in response to a processing request from the user (S7), and ends the process.

  On the other hand, if it is determined that there is similarity as a result of the similarity determination process, the control unit 7 causes the compression / decompression processing unit 35 to compress the input image data to generate compressed image data (S8), and the generated compressed image Data is stored in the image data storage unit 104 in the administrator folder 8A (S9). In this embodiment, the compressed image data is stored. However, the present invention is not limited to this. For example, the input image data may be stored without being compressed. A method for storing image data will be described later.

  Further, the control unit 7 displays an inquiry to the display unit of the operation panel 6 that the execution of the requested image processing cannot be permitted and whether or not to continue the image processing (S10). At this time, when image processing is continued, user authentication is required and user information and logs are recorded (or notified to the administrator (the notification signal in FIG. 1 is output)). You may make it display that.

  Next, the control unit 7 determines whether or not the user desires to continue the image processing based on the user input content on the operation panel 6 (S11). If it is determined that the image processing is not desired to be continued, the process is terminated.

  On the other hand, if it is determined that it is desired to continue the image processing, the control unit 7 displays on the display unit of the operation panel 6 to prompt the user information (user ID and password) and the user input by the user. Information is acquired (S12). Here, the user operates the operation panel 6 to input a user ID and password as user information. However, the present invention is not limited to this, for example, a card reader (not shown) provided in the digital color multifunction peripheral 1. User information may be read from the personal card inserted into the card. Further, in the case of a processing request from an external device (such as a computer) that is communicably connected to the digital color multifunction peripheral 1, a signal requesting transmission of user information is transmitted to the external device and transmitted from the external device. You may make it acquire the user information to be received.

  Next, the control unit 7 compares the acquired user information with the user information stored in the user information storage unit 102 and performs an authentication process as to whether or not the user should be allowed to continue the image processing ( S13).

  If the acquired user information does not match the user information stored in the user information storage unit 102 (authentication failure), the control unit 7 increments the value of Cp by 1 (Cp = Cp + 1) ( S14), it is determined whether or not Cp> K (S15). If Cp> K, the continuation of the image processing is not permitted (S16), and the process ends. On the other hand, if Cp ≦ K, the process returns to S12 to accept re-input of user information.

  When the user information acquired in S13 matches the user information stored in the user information storage unit 102 (authentication success), the control unit 7 compresses / decompresses the compressed image data stored in the image data storage unit 104. The processing unit 35 decompresses the image data (S17), permits the image processing to be continued (S18), and stores the input image data (or compressed image data) and a log related to the input image data in the administrator folder 8A (S19). The process ends. At this time, the control unit 7 may notify a predetermined transmission destination that the image processing on the input image data determined to be similar has been performed via the communication device 5. Further, the control unit 7 may transmit the input image data (or compressed image data) and the log to the predetermined transmission destination via the communication device 5. Alternatively, a user ID may be superimposed on a part of the input image data, and the user ID may be displayed on a part of the output image when the input image data is displayed, printed (image formation), or the like. Further, when the compressed image data is stored in the image data storage unit 104 in the administrator folder 8A in response to a processing request from an external device (computer or the like) that is communicably connected to the digital color multifunction peripheral 1 (when the user When no data is output at the time of arrival at the digital color multifunction peripheral 1), it is displayed that user authentication is required to continue image processing, and that user information and logs are recorded, and thereafter When the user authentication is successful, a job may be selected and output. The input image data (or compressed image data) and the log recording method will be described later.

(1-4. Image data, user information, and log storage method)
Next, a method for storing image data, user information, and logs will be described. FIG. 13 is an explanatory diagram showing a hierarchical structure in the administrator folder 8A. As shown in the figure, an image data storage unit (image data folder) 104 is provided in the administrator folder 8A. Further, an image processed folder and an unprocessed folder are provided in a lower hierarchy of the image data storage unit 104.

  When storing the compressed image data in the image data storage unit 104 in the process of S9, the control unit 7 stores the compressed image data in an unprocessed folder. At this time, the file name of the compressed image data is set to a file name based on the document ID, for example.

  Further, when storing the input image data (or compressed image data) and log in the image data storage unit 104 in the process of S19, the control unit 7 stores the input image data (or compressed image data) and log in the image processed folder. Store. Specifically, the control unit 7 creates a user folder for each user in the lower hierarchy of the image processed folder, and stores input image data (or compressed image data) and a log in the user folder corresponding to the user information. At this time, as shown in FIG. 13, the control unit 7 changes the file name of the image data to be stored and the file name of the log to a file name corresponding to the user information (file name including the user ID) and stores it. Also good. Alternatively, the user ID (user information) may be inserted and stored in the image data to be stored or the header portion of the log.

  Alternatively, as shown in FIG. 14, an image folder for storing image data and a log folder for storing logs are provided in a lower hierarchy of the image processed folder, and the control unit 7 stores the file name and log of the image data to be stored. The file name may be changed to a file name corresponding to the user information (file name including the user ID) and stored in the image folder and the log folder.

  As described above, the digital color multifunction peripheral 1 according to the present embodiment determines the similarity between the input image data and the registered image, and determines that the input image data is similar to the registered image. Alternatively, the compressed image data) is stored in the administrator folder 8A.

  Thereby, the administrator can easily determine the suitability of the determination result by accessing the administrator folder 8A and confirming the input image data (or compressed image data). Therefore, the administrator can take measures such as changing the threshold value TH <b> 2 related to similarity determination in order to suppress erroneous determination, for example, according to the suitability of the determination result. Further, unlike the technique of the above-mentioned Patent Document 5, there is no need to provide a paper discharge tray provided with a cover lock mechanism or a switching mechanism for switching the recording paper conveyance path, so that the apparatus configuration is increased in size and complexity. It is possible to realize an image processing apparatus that allows an administrator to easily confirm the suitability of a determination result without increasing the apparatus cost.

  When it is determined that there is similarity as a result of the similarity determination, the control unit 7 inquires the user whether or not to continue the image processing, and if the user desires to continue, information for specifying the user. The log relating to the input image data is stored in the administrator folder 8A, and the execution of the image processing is permitted. Thereby, the administrator can specify input image data on which image processing has been executed and a user who has executed the image processing.

  In addition, the control unit 7 stores in advance user information of a user who is permitted to continue image processing when it is determined that there is similarity, and the user can continue image processing when it is determined that there is similarity. If desired, user authentication is performed to determine whether or not to allow continuation of image processing. Thereby, users who can execute image processing on input image data determined to have similarity can be limited to specific users, and security can be improved.

  Further, when storing image data determined to be similar, the image data that has been subjected to image processing and the image data that has not been subjected to image processing are stored in separate folders. As a result, the administrator can quickly identify the image data that has been subjected to image processing.

  Further, when storing image data that has been subjected to image processing, the file name of the image data is changed to a file name corresponding to the user information and stored. Thereby, the user who performed the image processing can be quickly identified.

  In the present embodiment, the input image data (or compressed image data) is stored in the administrator folder 8A when it is determined that there is similarity as a result of the similarity determination process, but the present invention is not limited to this. . For example, the threshold value (second threshold value) TH2 for determining similarity may be different from the threshold value (first threshold value) TH1 for determining whether or not to store input image data in the administrator folder 8A.

  FIG. 15 shows a threshold (second threshold) TH2 for determining similarity to the similarity (for example, the ratio of the number of votes of each registered image to the total number of feature points) calculated by the voting processing unit 33. It is explanatory drawing which shows an example of the relationship with threshold value (1st threshold value) TH1 for determining whether input image data is stored in the administrator folder 8A. In the example shown in this figure, the threshold value TH2 is set to 80%, and the first threshold value TH1 is set to 70%.

  Accordingly, as shown in FIG. 15, when the similarity is 70% or more and less than 80% (first threshold value TH1 or more and less than second threshold value TH2), the control unit 7 performs image processing (copying) on the input image data. Printing, transmission, editing, etc.) and this input image data (or compressed image data) is stored in the administrator folder 8A. Thereby, although it is determined that there is no similarity, input image data that has a relatively high similarity and may be a registered image (the image data of the registered image may be erroneously determined as not similar) Input image data) can be stored in the administrator folder 8A. Therefore, the administrator can confirm the input image data later and determine whether the determination result is appropriate.

  In this embodiment, when it is determined that there is similarity and the user desires to continue the image processing, the control unit 7 stores the input image data, the user ID, and the log in the administrator folder 8A. The image processing is allowed to continue after being stored. However, the present invention is not limited to this, and a third threshold value TH3 (for example, 90%) larger than the second threshold value TH2 (for example, 80%) for similarity determination is set, and the degree of similarity is greater than or equal to the second threshold value TH2 and third If it is less than the threshold TH3 and the user desires, the image processing is allowed to continue, whereas if the similarity is equal to or greater than the third threshold TH3, the image processing is prohibited from continuing regardless of the user's wish ( Alternatively, it may be limited).

  As a result, when the similarity is equal to or greater than the third threshold TH3, the possibility of erroneous determination is low, so that the continuation of image processing can be prohibited (or restricted) regardless of the user's wish, and security can be improved. .

  Further, when the similarity is equal to or higher than the second threshold TH2 and lower than the third threshold TH3, there is a possibility that it is an erroneous determination that is determined to be similar although it is not originally image data of a registered image. Therefore, if the user desires, it is possible to permit the continuation of the image processing after storing the input image data, user information, and log in the administrator folder. Accordingly, it is possible to prevent the processing from being delayed due to an erroneous determination and to specify the user who has performed the image processing and the input image data later, so that the minimum security can be ensured.

  When the input image data whose number of votes (similarity) does not reach the second threshold value TH2 and exceeds the first threshold value TH1 is stored in the administrator folder 8A, it is not shown in FIG. 13 or FIG. The number of votes (similarity) obtained in the processing folder may be stored together with the input image data exceeding the second threshold TH2, or a folder different from the unprocessed folder may be created and stored.

  In the present embodiment, the case where the present invention is applied to the digital color multifunction peripheral 1 has been described. However, the application target of the present invention is not limited to this. For example, the present invention may be applied to a monochrome multifunction device. Further, the present invention is not limited to a multifunction machine, and may be applied to, for example, a single facsimile communication apparatus, a copying machine, an image reading apparatus, or the like.

  FIG. 16 is a block diagram showing a configuration example when the present invention is applied to a flatbed scanner (image reading apparatus, image processing apparatus) 1 ′.

  As shown in this figure, the flatbed scanner 1 'includes a color image input device 2 and a color image processing device 3'. The color image processing device 3 ′ includes an A / D conversion unit 11, a shading correction unit 12, a document collation processing unit 13, a control unit 7 (not shown in FIG. 16), and a memory 8 (not shown in FIG. 16). The color image input device 2 is connected to the image reading device 1 ′ as a whole. The functions of the A / D conversion unit 11, the shading correction unit 12, the document collation processing unit 13, the control unit 7, and the memory 8 in the color image input device (image reading unit) 2 are substantially the same as those of the digital color multifunction peripheral 1 described above. Since it is the same, description is abbreviate | omitted here.

  In the present embodiment, the administrator folder 8A is provided in the digital color multifunction peripheral 1. However, the present invention is not limited to this. For example, an external device (server apparatus) connected to the digital color multifunction peripheral 1 so as to be communicable is used. Etc.) may be provided with an administrator folder 8A.

  17 shows a server device 50 having an administrator folder 8A, and multifunction devices (MFPs) A, B,..., Printers A, B,. .. Configuration of image processing system 100 including facsimile machines A, B,..., Computers A, B,..., Digital cameras A, B,. It is explanatory drawing which shows. The configuration of the image processing system 100 is not limited to this. For example, the server device 50, a multifunction device, a printer (image forming device), a facsimile, a computer, a digital camera (image reading device), a scanner (image reading device). ) May be included.

  The scanner includes a document table, an optical scanning unit, a CCD (charge coupled device), etc., and scans the document image placed on the document table by the optical scanning unit to read the document image and generate image data. To do. The digital camera includes an imaging lens, a CCD, and the like (image input device), and shoots a document image, a person, a landscape, and the like to generate image data. The scanner and the digital camera may have a function of performing predetermined image processing (for example, various correction processes) in order to appropriately reproduce the image. The printer prints an image based on image data generated by a computer, a scanner, and a digital camera on a sheet (recording paper). Further, the facsimile performs processing such as binarization processing, resolution conversion processing, and rotation on the image data read from the image input device, and transmits the image data compressed to a predetermined format to the other party. The image data transmitted from the other party is decompressed and subjected to rotation processing, resolution conversion processing, and halftone processing according to the performance of the image output device, and output as an image in page units. The multifunction machine has at least two of a scanner function, a facsimile transmission function, and a printing function (copying function, printer function). The computer edits image data read by a scanner or a digital camera, or creates a document using application software.

  Each of the above devices connected to the server device 50 via the network includes a control unit 7 and a document collation processing unit 13. As a result of the similarity determination, when it is determined that there is similarity (the input image data is the image data of the registered image), the control unit 7 transmits the input image data, the device ID, etc. (the input image data is transmitted to the server device 50). Information for specifying the device) is transmitted to the server device 50, and the control unit (not shown) of the server device 50 stores the received information in the administrator folder 8A provided in the server device 50. ing. If it is determined that there is a similarity, and the user wishes to continue the process and, as a result of the user authentication process, permits the process to be continued, the control unit 7 logs the input image data and The server ID 50 is transmitted to the server device 50, and the control unit (not shown) of the server device 50 stores the received information in the administrator folder 8A provided in the server device 50.

  In the present embodiment, the similarity determination process is performed by the document collation processing unit 13 provided in the digital color multifunction peripheral 1, but the present invention is not limited to this. For example, some or all of the functions of the control unit 7 and the document collation processing unit 13 may be executed by an external device that is communicably connected to the digital color multifunction peripheral 1.

  FIG. 18 is a block diagram illustrating a configuration example when the server device 50 includes some of the functions of the control unit 7 and the document matching processing unit 13.

As shown in FIG. 18, the color image processing apparatus 3 of the digital color multifunction peripheral 1 controls the operation of the document collation processing unit 13a including the feature point calculation unit 31 and the feature amount calculation unit 32 and the document collation processing unit 13a. Control unit 7a, a memory 8a for storing information necessary for processing of the document collation processing unit 13a, and a communication device 5 for communicating with an external device. In addition, the server device 50 includes a communication device 51 that performs communication with an external device, a voting processing unit 33, a similarity determination processing unit 34, a compression / decompression processing unit 35, a registration processing unit 37, and a registration processing unit 37. A document collation processing unit 13b, a control unit 7b that controls the document collation processing unit 13b, and a memory 8b that stores information necessary for the processing of the document collation processing unit 13b are provided. When data transmission / reception is required between each functional block provided in the digital color multifunction peripheral 1 and each functional block provided in the server device 50, the control unit 7a and the control unit 7b are connected to the communication devices 5 and 51, respectively. To transmit and receive data as appropriate. Other functions are the same as those described above.

  In the example of FIG. 18, all of the feature amount calculation unit 32 (the feature point extraction unit 32 a, the invariant calculation unit 32 b, and the hash value calculation unit 32 c) are provided in the digital color multifunction peripheral 1, but this is not limitative. Instead, for example, as shown in FIG. 19, the feature point extraction unit 32 a and the invariant calculation unit 32 b may be provided in the digital color multifunction peripheral 1, while the hash value calculation unit 32 c may be provided in the server device 50.

  Each unit of the feature amount calculation unit 32 is provided in the server device 50, and data related to the feature points calculated by the feature point calculation unit 31 is transmitted from the digital color multifunction peripheral 1 to the server device 50, and is provided in the server device 50. The feature amount calculation unit 32 may calculate a hash value based on the hash table 103 stored in the memory 8b and the received feature point data. Further, the feature point calculation unit 31 and the feature amount calculation unit 32 are provided in the server device 50, and input image data is transmitted from the digital color multifunction peripheral 1 to the server device 50 to calculate the feature points provided in the server device 50. The unit 31 and the feature amount calculation unit 32 may calculate the hash value based on the input image data received from the server device 50 and the hash table 103 stored in the memory 8b.

  Further, in the above description, an example in which the similarity determination process is performed has been described. However, in the case of performing the registration process, the registration processing unit 37 provided in the server device 50 has received from the digital color multifunction peripheral 1. The document ID and the hash value (or the hash value calculated by the hash value calculation unit 32c provided in the server device 50) may be registered in the hash table 103 provided in the memory 8b. Whether the similarity determination process or the registration process is performed is designated by the user of the digital color multifunction peripheral 1 via the operation panel 6, and a signal indicating which process is performed is transmitted to the server device 50. Alternatively, the registration process may be performed for the input image that the server device 50 has determined as not similar as a result of the similarity determination process.

  When the server device 50 includes the hash value calculation unit 32c, the hash value is calculated and calculated using a method different from the hash value calculation method stored in the hash table 103 (using another hash function). The hash table 103 may be updated using a hash value. As a result, for example, an appropriate hash value referring to a feature value (invariant) according to the type of document image or the like can be registered (updated) in the hash table 103, and voting processing can be performed using it. The accuracy (similarity determination accuracy) can be improved.

  In this embodiment, when it is determined that there is similarity as a result of the similarity determination, the input image data is stored in the administrator folder 8A. In addition to this, for example, OCR (Optical Character Recognition) processing The character information extracted from the input image data may be stored. In this case, for example, the digital color multifunction peripheral 1 is provided with an OCR processing unit that extracts character information (text data) from the input image data, and the control unit 7 uses the administrator folder 8A for the text data extracted by the OCR processing unit. Can be stored in the.

[Embodiment 2]
Another embodiment of the present invention will be described. For convenience of explanation, members having the same functions as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 22 is a block diagram showing a schematic configuration of a digital color multifunction peripheral (image processing apparatus, image forming apparatus, image reading apparatus) 1 according to the present embodiment. As shown in this figure, in addition to the configuration of the digital color multifunction peripheral 1 according to the first embodiment, the digital color multifunction peripheral 1 according to the present embodiment includes an encryption / decryption processing section 38 in the document matching processing section 13. And the administrator folder 8A includes an encryption key storage unit 105. Other configurations are the same as those of the first embodiment.

  The encryption / decryption processing unit 38 encrypts the image data compressed by the compression / decompression processing unit 35 and stores it in the image data storage unit 104 of the administrator folder 8A. Further, the image data encrypted and stored in the image data storage unit 104 is decrypted, and the decrypted compressed image is decompressed and output to the input tone correction unit 14.

  The encryption key storage unit 105 stores and manages (stores) the encryption key for decrypting the image data encrypted by the encryption / decryption processing unit 38 in association with the encrypted image data. In this embodiment, when the encryption / decryption processing unit 38 encrypts image data, a unique value is assigned as an encryption key for each image data, and the encryption key and the image data are associated with each other for encryption. Stored in the key generation storage unit 105. In addition, when decrypting image data, the encryption key corresponding to the image data to be decrypted is read from the encryption key storage unit 105 and decrypted.

  FIG. 23 is a flowchart showing the flow of processing in the digital color multifunction peripheral 1.

  First, when receiving an instruction input (image processing request) from the user via the operation panel 6 or the communication device 5, the control unit 7 initializes the number of times Cp of user information to be stored in the memory 8 (Cp = 0). (S21).

  Next, the control unit 7 acquires input image data (S2). For example, input image data may be acquired by reading a document image with the color image input device 2, or input image data may be acquired from an external device by the communication device 5, and is provided in the digital color multifunction peripheral 1. Input image data may be read and acquired from various recording media via a card reader (not shown) or the like.

  Next, the control unit 7 controls each part of the document matching processing unit 13 to perform a feature point calculation process (S23), a feature amount calculation process (S24), a voting process (S25), and a similarity determination process (S26). Make it.

  When it is determined that there is no similarity as a result of the similarity determination process, the control unit 7 performs image processing according to a processing request from the user (for example, image formation by the color image output device 4 or via the communication device 5). (Transmission to the outside etc.) is permitted (S27), and the process is terminated.

  On the other hand, when it is determined that there is similarity as a result of the similarity determination process, the control unit 7 causes the compression / decompression processing unit 35 to compress the input image data and generate compressed image data (S28). Then, the generated compressed image data is encrypted by the encryption / decryption processing unit 38 to generate encrypted image data (S29), and information (encrypted image data) that associates the encrypted image data with the encryption key. (Information indicating the correspondence between the encryption key and the encryption key) is stored (registered) in the encryption key storage unit 105 (S30). Further, the encrypted image data generated in S29 is stored in the image data storage unit 104 in the administrator folder 8A (S31).

  In this embodiment, after compressing the input image data, the compressed image data is encrypted. However, the present invention is not limited to this. For example, the input image data may be encrypted as it is. May be performed simultaneously.

  The method for encrypting the image data is not particularly limited, and various conventionally known methods can be used. For example, Data Encryption Standard or Advanced Encryption Standard, which are general common key ciphers, may be used. In addition, an encryption method that allows only a specific user to decrypt one file may be used. In this case, a public key encryption such as RSA encryption may be used. In addition, when emphasizing data security, for example, as in the encryption method disclosed in Patent Document 6, a time key is generated, and even when the encryption key is disclosed to the user, a certain time or more is required. And may not be able to be decrypted.

  In addition, the control unit 7 displays an inquiry indicating that execution of the requested image processing cannot be permitted and whether or not to continue image processing is desired on the display unit of the operation panel 6 (S32). At this time, when image processing is continued, user authentication is required and user information and logs are recorded (or notified to the administrator (the notification signal in FIG. 1 is output)). You may make it display that.

  Next, the control unit 7 determines whether or not the user desires to continue the image processing based on the user input to the operation panel 6 (S33). If it is determined that the image processing is not desired to be continued, the process is terminated.

  On the other hand, if it is determined that it is desired to continue the image processing, the control unit 7 displays on the display unit of the operation panel 6 to prompt the user information (user ID and password) and the user input by the user. Information is acquired (S34). Here, the user operates the operation panel 6 to input a user ID and password as user information. However, the present invention is not limited to this, for example, a card reader (not shown) provided in the digital color multifunction peripheral 1. User information may be read from the personal card inserted into the card. Further, in the case of a processing request from an external device (such as a computer) that is communicably connected to the digital color multifunction peripheral 1, a signal requesting transmission of user information is transmitted to the external device and transmitted from the external device. You may make it acquire the user information to be received.

  Next, the control unit 7 compares the acquired user information with the user information stored in the user information storage unit 102 and performs an authentication process as to whether or not the user should be allowed to continue the image processing ( S35).

  If the acquired user information does not match the user information stored in the user information storage unit 102 (authentication failure), the control unit 7 increments the value of Cp by 1 (Cp = Cp + 1) ( S36), it is determined whether or not Cp> K (S37). If Cp> K, the continuation of the image processing is not permitted (S38), and the process ends. On the other hand, if Cp ≦ K, the process returns to S34 to accept re-input of user information.

  If it is determined in S35 that the user information acquired in S34 matches the user information stored in the user information storage unit 102 (successful authentication), the control unit 7 stores the image data in the image data storage unit 104. The stored encrypted image data is decrypted by the encryption / decryption processing unit 38 (S39), and the decrypted compressed image data is decompressed by the compression / decompression processing unit 35 (S40). Then, while allowing the image processing to continue (S41), the input image data (or compressed image data) and a log related to the input image data are stored in the administrator folder 8A (S42), and the processing is terminated.

  In the example of FIG. 23, the encrypted color image data is decrypted in the digital color multifunction peripheral 1. However, the present invention is not limited to this. For example, the encrypted image data is transmitted to the external device via the communication device 5. The external device may acquire the encryption key from the digital color multifunction peripheral 1 and decrypt it. FIG. 24 is a flowchart showing the flow of processing in this case.

  First, the control unit 7 acquires an image transmission request and input image data from the user via the operation panel 6 or the communication device 5 (S51). For example, input image data may be acquired by reading a document image with the color image input device 2, or input image data may be acquired from an external device by the communication device 5, and is provided in the digital color multifunction peripheral 1. Input image data may be read and acquired from various recording media via a card reader (not shown) or the like.

  Next, the control unit 7 controls each part of the document matching processing unit 13 to perform a feature point calculation process (S52), a feature amount calculation process (S53), a voting process (S54), and a similarity determination process (S55). Make it.

  When it is determined that there is no similarity as a result of the similarity determination process, the control unit 7 causes the compression / decompression processing unit 35 to compress the input image data to generate compressed image data (S56), and the generated compressed image Data is transmitted to the external device instructed by the image transmission request via the communication device 5 (S57), and the process is terminated. Thereby, the compressed image data received by the external device can be expanded to obtain input image data.

  On the other hand, if it is determined that there is similarity as a result of the similarity determination process, the control unit 7 causes the compression / decompression processing unit 35 to compress the input image data and generate compressed image data (S58). Then, the generated compressed image data is encrypted by the encryption / decryption processing unit 38 to generate encrypted image data (S59), and information (encrypted image data) that associates the encrypted image data with the encryption key. (Information indicating the correspondence between the encryption key and the encryption key) is stored (registered) in the encryption key storage unit 105 (S60). Further, the encrypted image data generated in S59 is stored in the image data storage unit 104 in the administrator folder 8A (S61).

  Next, the control unit 7 sends the encrypted image data and the inquiry destination information of the encryption key for decrypting the encrypted image data (information indicating the inquiry destination of the decryption method) to the image transmission request. Then, the data is transmitted to the external device instructed via the communication device 5 (S62). For example, when sending an image by e-mail, the inquiry destination may be described in the email, or a text file describing the image file and the inquiry destination information may be packed and transmitted. .

  Thereafter, the control unit 7 monitors whether there is an encryption key inquiry from an external device (S63). If there is an inquiry about the encryption key, it is determined whether or not the use of the input image data is permitted (S64). This determination may be performed based on, for example, the result of user authentication or external device authentication, or may be determined individually by the administrator.

  Then, when permitting the use of the input image data, the control unit 7 stores the inquiry destination information and log in the administrator folder 8A, and sends the encryption key corresponding to the input image data from the encryption key storage unit 105. The data is read and transmitted to the external device via the communication device 5 (S65), and the process is terminated. Accordingly, the external device can receive the encrypted image data transmitted in S62 and the encryption key transmitted in S65, and decrypt the encrypted image data based on the encryption key. . Then, the original input image data can be obtained by expanding the compressed image data obtained by decoding.

  On the other hand, when the use of the input image data is not permitted, the control unit 7 transmits that the use of the input image data is not permitted to the external device via the communication device 5 (S66), and ends the process.

  As described above, in this embodiment, when it is determined that the original of the input image data is similar to the original of the registered image, the input image data or the compressed image data obtained by compressing the input image data is encrypted / decrypted. The data is encrypted by the conversion processing unit 38 and stored in the administrator folder 8A.

  Thereby, the security regarding input image data can be improved. For example, even when the memory 8 in which the administrator folder 8A is provided is illegally taken out by physical means, it is possible to prevent the input image data from being used illegally or leaked. Note that the encryption key storage unit 105 that stores the encryption key and the image data storage unit 104 that stores the encrypted image data may be stored in different memories (hardware). As a result, the security of the encrypted image data can be further improved.

  In the configuration of the first embodiment, registered image (important image data (important documents)) and image data having a high degree of similarity are stored in the administrator folder (access restriction storage unit) 8A. Therefore, when the memory 8 (for example, a storage device such as a hard disk) having the administrator folder 8A is physically taken out, leakage of information similar to the registered image (important image data) cannot be prevented. That is, since an image having a high degree of similarity with the important document is stored in the administrator folder 8A, there is a high risk that these pieces of information are stolen in a lump. On the other hand, according to the configuration of the present embodiment, the image data is encrypted and stored in the administrator folder 8A, so even if the memory 8 having the administrator folder 8A is physically stolen or the like. Information leakage can be prevented.

  In this embodiment, a unique value is assigned to each image data as an encryption key for decrypting the encrypted image data, and is stored in the encryption key storage unit 105 in association with the target image data. . As a result, when the image processing for the input image data is permitted, it can be appropriately decrypted using the encryption key. It is also possible to present the encryption key to the user so that the user can decrypt the encrypted image data. Thus, for example, when a user who wishes to output encrypted image data follows the normal procedure and obtains permission from the administrator, an encryption key for decrypting the encrypted image data is issued to the user. And allow output. Further, it is possible to permit decryption of the encrypted image data without waiting for the administrator's permission on condition that personal information (ID) registered in advance is input.

  In each of the above embodiments, each unit (each block) constituting the document collation processing unit and the control unit provided in the digital color multifunction peripheral 1 and / or the server device 50 is realized by software using a processor such as a CPU. The That is, the digital color multifunction peripheral 1 and / or the server device 50 develops a central processing unit (CPU) that executes instructions of a control program that realizes each function, a read only memory (ROM) that stores the program, and the program. A random access memory (RAM), and a storage device (recording medium) such as a memory for storing the program and various data. An object of the present invention is to read the program code (execution format program, intermediate code program, source program) of the control program of the digital color multifunction peripheral 1 and / or the server device 50, which is software that realizes the functions described above, with a computer. This is achieved by supplying the recording medium recorded as possible to the digital color multifunction peripheral 1 and / or the server device 50, and reading out and executing the program code recorded on the recording medium by the computer (or CPU or MPU). .

  Examples of the recording medium include tapes such as magnetic tapes and cassette tapes, magnetic disks such as floppy (registered trademark) disks / hard disks, and disks including optical disks such as CD-ROM / MO / MD / DVD / CD-R. Card system such as IC card, IC card (including memory card) / optical card, or semiconductor memory system such as mask ROM / EPROM / EEPROM / flash ROM.

  Further, the digital color multifunction peripheral 1 and / or the server device 50 may be configured to be connectable to a communication network, and the program code may be supplied via the communication network. The communication network is not particularly limited. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication. A net or the like is available. Also, the transmission medium constituting the communication network is not particularly limited. For example, even in the case of wired such as IEEE 1394, USB, power line carrier, cable TV line, telephone line, ADSL line, etc., infrared rays such as IrDA and remote control, Bluetooth ( (Registered trademark), 802.11 wireless, HDR, mobile phone network, satellite line, terrestrial digital network, and the like can also be used. The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission.

  In addition, each block of the digital color multifunction peripheral 1 and / or the server device 50 is not limited to being realized using software, and may be configured by hardware logic, and performs a part of the processing. A combination of hardware and arithmetic means for executing software for controlling the hardware and performing the remaining processing may be used.

  The computer system of the present invention includes an image input device such as a flatbed scanner, a film scanner, and a digital camera, a computer in which various processes such as the similarity calculation process and the similarity determination process are performed by loading a predetermined program, You may comprise by image formation prosecution, such as an image display apparatus, such as a CRT display and a liquid crystal display which displays the process result of a computer, and a printer which outputs the process result of a computer on paper. Furthermore, a network card, a modem, or the like as communication means for connecting to a server or the like via a network may be provided.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. That is, embodiments obtained by combining technical means disclosed in different embodiments and technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The present invention can be applied to an image processing apparatus and an image processing method that determine the similarity between input image data and registered image data registered in advance, and perform control according to the determination result.

It is a block diagram which shows schematic structure of the document collation process part with which the image processing apparatus concerning one Embodiment of this invention is equipped. 1 is a block diagram illustrating a schematic configuration of an image processing apparatus according to an embodiment of the present invention. It is a block diagram which shows schematic structure of the feature point calculation part with which the image processing apparatus shown in FIG. 2 is equipped. It is explanatory drawing which shows an example of the filter coefficient of the mixing filter with which the MTF process part of the image processing apparatus shown in FIG. 2 is provided. FIG. 3 is an explanatory diagram illustrating an example of a connected region extracted from input image data by a feature point calculation unit of the image processing apparatus illustrated in FIG. 2 and a center of gravity of the connected region. It is explanatory drawing which shows an example of each gravity center (feature point) of the some connection area | region extracted from the character string contained in input image data by the feature point calculation part of the image processing apparatus shown in FIG. FIG. 3 is an explanatory diagram illustrating an example of a feature point of interest and peripheral feature points extracted when a feature amount is calculated by a feature amount calculation unit of the image processing apparatus illustrated in FIG. 2. (A)-(c) is explanatory drawing which shows an example of the combination of the attention feature point and surrounding feature point which are extracted when the feature-value calculation part of the image processing apparatus shown in FIG. 2 calculates a feature-value. . (A)-(c) is explanatory drawing which shows an example of the combination of the attention feature point and surrounding feature point which are extracted when the feature-value calculation part of the image processing apparatus shown in FIG. 2 calculates a feature-value. . (A) And (b) is explanatory drawing which shows an example of the index showing the hash value and input image data about each feature point registered into a hash table in the image processing apparatus shown in FIG. 3 is a graph showing an example of the number of votes for each registered image in the voting processing unit of the image processing apparatus shown in FIG. 2. It is a flowchart which shows the flow of a process in the image processing apparatus shown in FIG. FIG. 3 is an explanatory diagram showing an example of a hierarchical structure of an administrator folder 8A in the image processing apparatus shown in FIG. It is explanatory drawing which shows the other example of the hierarchical structure of the administrator folder 8A in the image processing apparatus shown in FIG. In the image processing apparatus shown in FIG. 2, an example of both threshold values when the threshold value for determining similarity is different from the threshold value for determining whether to store input image data in the administrator folder. It is explanatory drawing which shows. It is a block diagram which shows the modification of the image processing apparatus concerning one Embodiment of this invention. It is explanatory drawing which shows the structure of the image processing system concerning one Embodiment of this invention. 1 is a block diagram illustrating a configuration example of an image processing system according to an embodiment of the present invention. It is a block diagram which shows the other structural example of the image processing system concerning one Embodiment of this invention. (A)-(d) is description which shows an example of the combination of the attention feature point and peripheral feature point which are extracted when the feature-value calculation part of the image processing apparatus concerning one Embodiment of this invention calculates a feature-value. FIG. (A)-(d) is description which shows an example of the combination of the attention feature point and peripheral feature point which are extracted when the feature-value calculation part of the image processing apparatus concerning one Embodiment of this invention calculates a feature-value. FIG. It is a block diagram which shows schematic structure of the image processing apparatus concerning other embodiment of this invention. It is a flowchart which shows the flow of the image output process in the image processing apparatus shown in FIG. It is a flowchart which shows the flow of the image transmission process in the image processing apparatus shown in FIG.

Explanation of symbols

1 Digital color MFP (image processing device, image forming device, image reading device, image processing device)
1 'Flatbed scanner (image processing device, image reading device)
2 Color image input device (input data acquisition unit, image input device)
3,3 'color image processing device (image processing device)
4 color image output device (image output unit)
5 Communication devices (input data acquisition unit, transmission device)
6 Operation panel (Processing input section)
7, 7a, 7b Control unit 8, 8a, 8b Memory (storage unit)
8A Administrator folder (access restriction storage unit)
13, 13a, 13b Document collation processing unit (similarity calculation unit)
31 feature point calculation unit 32 feature amount calculation unit 32a feature point extraction unit 32b invariant calculation unit 32c hash value calculation unit 33 voting processing unit (similarity calculation unit)
34 similarity determination processing unit 35 compression / decompression processing unit 37 registration processing unit 38 encryption / decryption processing unit (encryption unit)
50 Server apparatus 100 Image processing system 101 Administrator information storage unit 102 User information storage unit 103 Hash table 104 Image data storage unit 105 Encryption key storage unit

Claims (21)

An input data acquisition unit that acquires input image data, a feature amount extraction unit that extracts the feature amount of the input image data, a storage unit that stores the feature amount of the registered image, and a registered image from an external device that is communicably connected At least one of the registered image acquisition units that acquire the feature amount of the input image, the similarity calculation unit that compares the feature amount of the input image data with the feature amount of the registered image, and calculates the similarity of both images, and the similarity An image processing apparatus including a control unit that controls processing on the input image data according to the degree,
When the similarity calculated by the similarity calculation unit is greater than or equal to a first threshold value set in advance, the control unit only receives the input image data or compressed image data obtained by compressing the input image data by a specific user. An image processing apparatus that is stored in an accessible access restriction storage unit. A processing input unit that receives a processing request for the input image data;
The control unit
When the similarity calculated by the similarity calculation unit is equal to or greater than a second threshold preset to a value equal to or greater than a first threshold, execution of processing according to the processing request for the input image data is prohibited or Limit
The execution of processing according to the processing request for the input image data is permitted when the similarity calculated by the similarity calculation unit is not less than a first threshold and less than a second threshold. Item 8. The image processing apparatus according to Item 1. A user information storage unit that stores user information for identifying a user who is permitted to execute the process on the input image data even when the similarity calculated by the similarity calculation unit is equal to or greater than a second threshold; And
The control unit
When the similarity calculated by the similarity calculation unit is greater than or equal to a second threshold, the user information input via the process input unit is accepted, and the user information input via the process input unit It is determined whether or not the matching user information exists in the user information stored in the user information storage unit. When the matching user information exists, the input image data or the input image data is The image processing apparatus according to claim 2, wherein the compressed compressed image data and user information are associated with each other and stored in the access restriction storage unit, and the execution of the process on the input image data is permitted. A display unit for presenting information to the user;
The control unit
If the similarity calculated by the similarity calculation unit is equal to or greater than a second threshold, the display unit displays a display prompting the user to input whether or not the processing for the input image data is desired,
The image processing apparatus according to claim 3, wherein when the user inputs a request for execution of processing through the processing input unit, the display unit displays a display prompting input of user information. . A log generation unit that generates log information related to the input image data;
The control unit
4. The image processing apparatus according to claim 3, wherein the input image data or compressed image data obtained by compressing the input image data, user information, and a log are associated and stored in the access restriction storage unit. The access restriction storage unit includes a first storage area and a second storage area,
The control unit
When the similarity calculated by the similarity calculation unit is equal to or greater than the second threshold, the input image data that has not been processed or the compressed image data obtained by compressing the input image data is stored in the first storage area, and the processing is performed. 4. The image processing apparatus according to claim 3, wherein the input image data that has been executed or the compressed image data obtained by compressing the input image data is stored in the second storage area. 5.   The control unit adds user information to the input image data that has been processed or the compressed image data obtained by compressing the input image data and stores the user information in the access restriction storage unit, or the input image data or the input image 4. The image processing apparatus according to claim 3, wherein a file name including user information is added to the compressed image data obtained by compressing the data and stored in the access restriction storage unit. The control unit
The similarity calculated by the similarity calculation unit is a value that is greater than or equal to the second threshold and less than a preset third threshold that is greater than the second threshold, and is input via the processing input unit If user information that matches the user information is present in the user information stored in the user information storage unit, the input image data or compressed image data obtained by compressing the input image data and user information are In association with storage in the access restriction storage unit, the execution of the processing for the input image data is permitted,
The image processing apparatus according to claim 3, wherein when the similarity calculated by the similarity calculation unit is equal to or greater than the third threshold, execution of processing on the input image data is prohibited. An encryption unit that generates encrypted image data obtained by encrypting the input image data or the compressed image data;
The said control part stores the said encryption image data in the said access restriction memory | storage part, when the similarity calculated by the said similarity calculation part is more than the preset 1st threshold value. The image processing apparatus according to 1.   The image processing apparatus according to claim 9, further comprising: an encryption key storage unit that stores encryption key information for decrypting the encrypted image data in association with the encrypted image data. A communication means for transmitting image data to an external device;
The control unit transmits the encrypted image data from the communication unit to an external device, and then sends the encrypted image when a request for transmission of an encryption key corresponding to the encrypted image data is received from the external device. The image processing apparatus according to claim 10, wherein an encryption key corresponding to data is transmitted from the communication unit to the external apparatus.   An image forming apparatus comprising: the image processing apparatus according to claim 1; and an image output unit that forms an image corresponding to input image data on a recording material.   An image transmission apparatus comprising: the image processing apparatus according to claim 1; and a transmission apparatus that transmits input image data to another apparatus that is connected to be communicable. An image input device that reads a document image and obtains input image data;
An image reading apparatus comprising: the image processing apparatus according to claim 1. An input data acquisition step of acquiring input image data;
A feature amount extraction step for extracting feature amounts of the input image data;
A registration data acquisition step for acquiring a feature amount of a registered image;
Image processing that includes a similarity calculation step of calculating the similarity between both images by comparing the feature amount of the input image data and the feature amount of the registered image, and controlling processing on the input image data according to the similarity A method,
A determination step of determining whether the similarity calculated in the similarity calculation step is equal to or greater than a preset first threshold;
When it is determined in the determination step that the similarity is greater than or equal to a first threshold, the input image data or compressed image data obtained by compressing the input image data is stored in an access restriction storage unit accessible only by a specific user. An image processing method comprising: a storing step. An image processing device and a server device connected to the image processing device so as to be communicable, an input data acquisition unit for acquiring input image data, and a feature amount extraction unit for extracting feature amounts of the input image data A storage unit that stores the feature amount of the registered image, a similarity calculation unit that compares the feature amount of the input image data with the feature amount of the registered image, and calculates the similarity between the two images, and according to the similarity An image processing system in which a control unit that controls processing on the input image data and an access restriction storage unit that can be accessed only by a specific user are distributed in the image processing device and the server device. ,
The control unit stores the input image data or the compressed image data obtained by compressing the input image data in the access restriction storage when the similarity calculated by the similarity calculation unit is equal to or greater than a preset first threshold. An image processing system characterized by being stored in a unit. An encryption unit that generates encrypted image data obtained by encrypting the input image data or the compressed image data;
The said control part stores the said encryption image data in the said access restriction memory | storage part, when the similarity calculated by the said similarity calculation part is more than the preset 1st threshold value. 16. The image processing system according to 16.   18. The image processing system according to claim 17, further comprising: an encryption key storage unit that stores encryption key information for decrypting the encrypted image data in association with the encrypted image data.   The control unit responds to the encrypted image data from the other device after transmitting the encrypted image data from the device provided with the access restriction storage unit to the other device. 19. The image processing system according to claim 18, wherein an encryption key corresponding to the encrypted image data is transmitted to the external device when an encryption key transmission request is made.   The program for operating the image processing apparatus of any one of Claims 1-11, Comprising: The program for functioning a computer as said each part.   A computer-readable recording medium on which the program according to claim 20 is recorded.

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