JP4842778B2 - Image processing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that, although a processing to be executed is regulated when a specified image is detected in an input image data, possibility of unauthorized use is high and security measure is required if regulation frequency is high. <P>SOLUTION: A control part regulates to inhibit copying if the image data that is read from an original contains a specified image. The control part counts the frequency of regulation, and when the frequency of regulation within a specified period exceeds a specified number, the security level is raised. Thus, detection accuracy of specified image is raised, for easy detection of a specified image, resulting in strict regulation against unauthorized use. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to an image processing apparatus that restricts processing such as copying, facsimile communication, and data transmission based on a specific image included in image data.

  The image processing apparatus executes processing such as inputting image data and outputting it by copying, facsimile communication, or data communication. When a specific image is detected from the input image data, processing to be executed is restricted. As a result, unauthorized use of the image processing apparatus can be prevented and image data can be protected.

For example, Patent Document 1 describes that when a specific image is detected, the image data is changed to a white image and printed. Patent Document 2 describes that when a specific image is detected, the image data is deleted or the specific image is added to the read image data.
JP-A-4-343570 JP-A-11-355564

  As described above, in the image processing apparatus, the process to be executed is restricted every time a specific image is detected. Even if the specific image is detected a plurality of times, the regulation does not change. It is considered that the third party is illegally using the image processing device because it is frequently regulated. However, in spite of the possibility that the image processing apparatus is illegally used in this way, the image processing apparatus does not take any measures against unauthorized use. Therefore, the risk of leakage of image data is increased, and there is a security problem.

  In view of the above, an object of the present invention is to provide an image processing apparatus capable of enhancing protection of image data when unauthorized use is frequently performed.

  The present invention comprises an input means for inputting image data, a detection means for detecting a specific image in the image data, and a control means for restricting processing on the image data when the specific image is detected. The security level for image data protection is determined according to the frequency with which processing is regulated.

  If the frequency of regulations increases, there is a possibility that fraudulent use is more frequent. Therefore, by determining the security level according to the frequency of regulation, the current security level is changed, and security measures are strengthened.

  The control means increases the security level when the frequency of regulation is high. When the frequency of regulations is low, the security level is lowered. Increasing the security level increases the detection accuracy of the specific image, and the specific image is definitely detected. As a result, if the use is misleading, the processing is restricted and unauthorized use can be prevented. Also, if the frequency of regulation is low, there is little risk of unauthorized use, so the security level can be lowered.

  The control means counts the number of restrictions in a predetermined period, and determines whether the frequency is high or low. When the number of times of regulation is large, the frequency is high, and when the number of times of regulation is small, the frequency is low. As a result, it is possible to grasp the status of unauthorized use with respect to the image processing apparatus, and to take appropriate security measures against unauthorized use by changing the security level.

  The control means increases the security level when the number of times of regulation exceeds the predetermined number before the predetermined period elapses. When unauthorized use is concentrated, the number of restrictions exceeds the predetermined number before the predetermined period elapses. That is, when the frequency of regulation increases rapidly in a short period of time, the situation is as described above. Therefore, by immediately raising the security level, unauthorized use thereafter can be suppressed.

  The control means determines the detection criteria for the specific image, the additional condition for the specific image when processing the image data, the presence / absence of user authentication, and the processing restriction range according to the security level. Furthermore, the security level is determined for each user.

  By changing the detection criterion of the specific image, the detection accuracy of the specific image can be increased and the security level is increased. By changing the conditions for adding a specific image when processing the image data, when the image data is input after the image data with the specific image is output, the specific image is easily detected and the security level is increased. . By providing user authentication, unauthenticated users cannot be used and the security level is increased. By changing the scope of processing restriction, the number of restricted processes increases and the security level increases.

  According to the present invention, if the restriction of processing increases, the security level is raised, so that processing that could be illegally used before cannot be performed. Therefore, in an image processing apparatus that has been frequently used illegally, unauthorized use can be suppressed, leakage of image data can be prevented, and data protection can be enhanced.

  An image processing apparatus of this embodiment is shown in FIG. The image processing apparatus is a multifunction machine that executes a copy mode, a print mode, a scanner mode, and a facsimile mode. The image processing apparatus 2 reads an original and inputs image data into a cabinet 1 and processes the image data. The image forming unit 3 for printing, the storage unit 4 for storing the image data, the communication unit 5 for communicating with the external device, the operation panel 6 for input operation, and the processing unit are controlled, and the image according to the mode And a control unit 7 that executes data processing. The processing unit performs processing to output input image data, and includes the image forming unit 3, the storage unit 4, and the communication unit 5.

  As shown in FIG. 2, the image reading unit 2 is disposed above the cabinet 1 and includes a scanner unit 10 and an automatic document feeder 11. The automatic document feeder 11 is provided above the scanner unit 10 and automatically conveys a document in order to read image data of the document.

  A document table 12 made of platen glass is provided on the upper surface of the cabinet 1, and a document cover 13 that covers the document table 12 is provided. The automatic document feeder 11 is integrally mounted on the document cover 13. The document cover 13 can be freely opened and closed. When the document cover 13 is in a closed state, the document is conveyed by the automatic document conveyance unit 11. When the document cover 13 is open, the document can be placed on the document table 12. Opening / closing of the document cover 13 is detected by a cover opening / closing sensor. A document size detection sensor for detecting the size of the document placed on the document table 12 is also provided.

  When a document is set on the document set tray 15 of the automatic document feeder 11, the document detection sensor 16 detects that the document has been set. Then, on the operation panel 6, copy conditions such as the size of the sheet to be printed and the scaling ratio are input. Thereafter, reading of the image of the document is started by an input operation of the start key.

  In the automatic document feeder 11, each document on the document set tray 15 is pulled out one by one by the pickup roller 17. The document passes through between the separating plate 18 and the transport roller 19 and is sent to the document table 12. The document is transported in the sub-scanning direction on the document table 12 and discharged to the document discharge tray 20. The document discharge tray 20 is provided with a document discharge sensor to detect the presence or absence of a document on the document discharge tray 20.

  The scanner unit 10 includes a first reading unit 21 and a second reading unit 22. A reading area is formed on one side of the document table 12 and passes through the reading area when the document is conveyed on the document table 12. Below the reading area, the first scanning unit 23 of the first reading unit 21 is positioned, and the surface (lower side) of the document is read.

  When the document is transported to the document table 12 by the automatic document transport unit 11, the first scanning unit 23 is moved to the reading position and positioned, and the second scanning unit 24 is also positioned at a predetermined position. The surface of the document is irradiated from below the document table 12 by the exposure lamp of the first scanning unit 23. Reflected light from the document is guided to the imaging lens 25 by the respective reflection mirrors of the first and second scanning units 23 and 24. The reflected light of the document is condensed on the CCD 26 by the imaging lens 25. An image on the surface of the document is formed on the CCD 26. As a result, the image on the surface of the conveyed document is read.

  Further, the second reading unit 22 reads the back surface (upper side surface) of the document. The second reading unit 22 is disposed above the document table 12 and has an LED that irradiates the back side of the document, an exposure lamp array having a fluorescent lamp, a self-focal lens array that collects reflected light of the document for each pixel, and a cell. A contact image sensor (CIS) that photoelectrically converts reflected light from a document received through a fock lens array and outputs an analog image signal is provided. As a result, the image on the back side of the conveyed document is read.

  When a document is placed on the document table 12, the first reading unit 21 reads an image on the surface of the document. The first and second scanning units 23 and 24 move in the sub-scanning direction while maintaining a predetermined speed relationship with each other. The document on the document table 12 is exposed by the first scanning unit 23, and reflected light from the document is guided to the imaging lens 25 by the first and second scanning units 23 and 24. An image of the original is formed on the CCD 26 by the imaging lens 25.

  When the image on one or both sides of the document is read in this way, the image data on one or both sides of the document is input to the control unit 7. The control unit 7 includes an image data processing unit, and the image data processing unit performs various types of image processing on the image data. This image data is output to the image forming unit 3.

  The image forming unit 3 prints a color image or a monochrome image on the sheet based on the input image data. The image forming unit 3 includes a laser scanning unit 30, four image stations 31, an intermediate transfer belt unit 32, a fixing device 33, and a conveying device 34.

  Each image station 31 forms a color image corresponding to each color of black, cyan, magenta, and yellow. Each image station 31 includes a photosensitive drum 35, a developing device 36, a charging device 37, a cleaning device 38, and a charge eliminating device (not shown).

  The photosensitive drum 35 is rotationally driven in one direction, the cleaning device 38 cleans the residual toner on the surface of the photosensitive drum 35, and the neutralization device neutralizes the surface of the photosensitive drum 35. The charging device 37 uniformly charges the surface of the photosensitive drum 35.

  The laser scanning unit 30 modulates laser light based on image data input from an image reading unit or the like, and repeatedly scans the surface of the photosensitive drum 35 in the main scanning direction with this laser light, thereby generating an electrostatic latent image. It is formed on the surface of the photosensitive drum 35. The developing device 36 supplies toner to the surface of the photosensitive drum 35 to develop the electrostatic latent image, and forms a toner image on the surface of the photosensitive drum 35.

  The intermediate transfer belt unit 32 includes an intermediate transfer belt 40, an intermediate transfer roller 41, a transfer belt cleaning device 42, and a tension mechanism 43. The intermediate transfer belt 41 is disposed above each photosensitive drum 35, is wound around the driving roller 44 and the driven roller 45, and rotates in the direction of arrow B.

  The intermediate transfer roller 41 is disposed to face the photosensitive drum 35 with the intermediate transfer belt 40 interposed therebetween, and a transfer bias voltage is applied thereto. The toner image on the surface of the photosensitive drum 35 is transferred to the intermediate transfer belt 40 by applying a voltage having a polarity opposite to that of the toner by the intermediate transfer roller 41. The toner images of the respective colors are laminated on the intermediate transfer belt 40, and a combined multi-color toner image is formed.

  The transfer roller 41 is disposed in pressure contact with the intermediate transfer belt 40, and a voltage having a polarity opposite to that of the toner is applied. The toner image on the intermediate transfer belt 40 is transferred onto the sheet conveyed between the transfer roller 46 and the intermediate transfer belt 40 by the transfer roller 46. The toner remaining on the intermediate transfer belt 40 is removed by the transfer belt cleaning device 42.

  The toner image transferred to the sheet is heated and pressurized by the fixing device 33 and fixed on the sheet, and an image is formed on the sheet. The sheet on which the image is printed in this manner is discharged to a discharge tray 50 provided at the top of the cabinet 1.

  The transport device 34 transports the sheet from the sheet cassette 51 or the manual feed tray 52 along the transport path 53. The conveyance path 53 passes between the intermediate transfer belt 40 and the transfer roller 46, passes through the fixing device 33, and reaches the discharge tray 50.

  The transport device 34 includes a pickup roller 54, a transport roller 55, a registration roller 56, and a discharge roller 57. The sheets in the sheet cassette 51 or the manual feed tray 52 are sent one by one to the transport path 53, transported through the transport path 53, and discharged to the discharge tray 50. An image is printed on the sheet during conveyance of the sheet. In addition, a switchback conveyance path 58 is provided for duplex printing. The sheet after fixing passes through the switchback conveyance path 58 by the conveyance roller 55 and is conveyed between the intermediate transfer belt 40 and the transfer roller 46. The sheet printed on both sides passes through the fixing device 33 and is discharged to the discharge tray 50.

  The operation panel 6 is provided in the scanner unit 10 and includes an operation unit 60 and a display unit 61. The operation unit 60 includes various operation keys. The display unit 61 includes a liquid crystal display and is a touch panel. Touch keys are formed in the operation screen displayed on the display unit 61, and these also function as operation keys.

  The communication unit 5 includes a communication interface, and the communication interface is connected to a network such as a LAN or a WAN. A plurality of external devices are connected to the network. The external device is another image processing device, an information processing device such as a personal computer, or a server. The network is connected to the Internet from a router through a communication line such as a telephone line or an optical fiber. The communication unit 5 can communicate with an external device through a network using a predetermined communication protocol. The image processing apparatuses can also communicate with each other. Communication within the network may be wired or wireless. An image processing system is formed by these image processing devices and external devices.

  The communication unit 5 includes a modem device. A telephone line is connected to the modem device. The image processing apparatus can perform facsimile communication. The image processing apparatus can also perform data communication by Internet facsimile through a network. Furthermore, the communication unit 5 includes a communication terminal and a communication card for wireless communication. A storage medium such as a USB memory or an IC card is connected to the communication terminal, and the communication unit 5 transmits / receives data to / from the storage medium. In addition, data is transmitted and received by wireless communication with a communication terminal such as a mobile phone or PDA through a communication card.

  The storage unit 4 includes a hard disk device. The storage unit 4 stores image data input from the image reading unit 2 or image data input from the communication unit 5. The input image data is temporarily stored in an image memory such as a DRAM, subjected to image processing and encryption processing, and then transferred from the image memory to the storage unit 4. Further, when image data is read from the storage unit 4, the image data is subjected to image processing and decoding processing and stored in an image memory. Thereafter, the image data is output to the outside by printing, data transmission, and facsimile communication according to the processing to be executed.

  The storage unit 4 includes a management table 62, and information necessary for operating the image processing apparatus such as control information, setting information, and user authentication information of the image processing apparatus is stored in the management table 62. When these pieces of information are created and changed, the information in the management table 62 is updated. The management table 62 may be provided in a non-volatile memory different from the storage unit 4.

  The control unit 7 includes a microcomputer having a CPU, a ROM, and a RAM. The CPU reads a control program stored in the ROM into the RAM and executes the control program. Each unit operates according to the control program.

  That is, when image data is input from the image reading unit 2 or the communication unit 5 functioning as an input unit, based on processing conditions included in input information from the operation unit 60 or header information of image data input from an external device. Then, one of the print mode, copy mode, scanner mode, and facsimile mode is executed. In addition, the control program includes a browser and mail software, and the control unit 7 performs data communication with an external device or transmits / receives an e-mail using a communication protocol such as a TCP / IP protocol.

  The control unit 7 temporarily stores the input image data in the storage unit 4 when performing each mode. Further, the control unit 7 executes a filing mode in which the input image data is stored in the storage unit 4 and managed. The stored image data is re-output according to the instructed process.

  The output image data is erased from the storage unit 4 according to an instruction from the control unit 7. At the time of this erasure, the image data is invalidated so that it cannot be restored by overwriting the image data with random data. In this way, invalidation of image data is prevented by performing invalidation processing and further encryption processing.

  Here, in order to prevent the confidential document from being illegally copied or transmitted by facsimile, a specific image is added to the document. The specific image represents restriction information for restricting processing to be executed such as copy prohibition, deterioration in print image quality, data transmission or facsimile communication prohibition, and filing prohibition.

  A specific image adding unit 63 for adding the specific image is provided. The specific image adding unit 63 is controlled in operation by the control unit 7, generates a specific image based on the determined additional condition, and synthesizes the specific image with the image data. The control unit 7 performs processing such as printing of the synthesized image data, data transmission, and filing.

  Additional conditions for the specific image are stored in the management table 62 in advance. The additional conditions include the form of the specific image, the image forming conditions, the number, the position, and the like. The specific image adding unit 63 reads the additional condition, generates a specific image based on the additional condition, and synthesizes it with the input image data.

  When the image data to which the specific image is added is printed, a document including the specific image as shown in FIG. 3 is created. The specific image is a predetermined image, for example, a form in which a plurality of dots are linearly arranged and have an inclined pattern. Specific images of the same form are regularly arranged at predetermined positions. A single page of the document includes a plurality of specific images. Note that the number of specific images per page is determined according to the page size. The density of the specific image and the angle of the inclined pattern are also determined. The angle is 45 degrees.

  Further, image data including the specific image is transmitted through the communication unit 5. When the image processing apparatus receives the image data and prints the image data, a document including the specific image is created.

  It is difficult for humans to visually recognize a specific image of a document. However, the specific image can be read by the image reading unit 2. Therefore, as a detecting unit for detecting a specific image in the input image data, a specific image determination unit 64 that detects whether the specific image is included in the image data and determines whether the specific image exceeds a threshold value. Is provided. The image data is not limited to those input from the image reading unit 2 but is input from an external device, a storage medium, or a communication terminal through the communication unit 5.

  The specific image determination unit 64 is controlled in operation by the control unit 7 and detects a specific image by performing pattern matching between the input image data and image data corresponding to the specific image. Image data corresponding to the specific image is registered in advance and stored in the management table 62. Then, the specific image determination unit 64 counts the number of detected specific images and determines whether or not the number of detected specific images exceeds a threshold value. When the image data is in page units, the number of specific images is calculated for each page. Alternatively, the number of specific images in a predetermined area area is calculated.

  The threshold value is set by an authorized user such as an administrator and stored in the management table 62. Authorized users are authenticated by inputting authentication information such as biometric information such as passwords and fingerprints. The authenticated user can set a threshold value through the operation unit 60.

  The control unit 7 regulates a process to be executed when the specific image is included in the input image data exceeding the threshold value. That is, when the control unit 7 detects that a specific image is included in the image data, the control unit 7 functions as a control unit that restricts processing on the image data. In the copy mode, copy prohibition is instructed, and in the facsimile mode or scanner mode, transmission prohibition is instructed. In the filing mode, the storage unit 4 is instructed to prohibit image data from being saved. In addition, even if the specific image is detected, the control unit 7 does not restrict the processing when the number does not exceed the threshold value.

  In this way, the image processing apparatus performs security measures to prevent unauthorized use of the image processing apparatus and protect image data by adding and detecting a specific image. When implementing security measures, the security level is determined. The higher the security level, the more strictly the regulation of processing to be executed, and the higher security can be realized.

  The control unit 7 executes restriction of addition, detection, and processing of a specific image according to the determined security level. Depending on the security level, specific image detection criteria, specific image additional conditions, user authentication, and processing restriction ranges are determined. The security level is set by the administrator, and the setting content is stored in the management table 62.

  The detection criteria for a specific image include a threshold and a similar range of the specific image. Specific image addition conditions include the number of specific images, image density, and angle. User authentication is the presence or absence of user authentication. The scope of processing includes prohibition of all processing, partial limitation of processing, and notification.

  In this image processing apparatus, when unauthorized use is frequently performed, the security level is changed to protect the image data. That is, the control unit 7 regulates the process when a specific image is detected. Then, the security level is determined according to the frequency with which the processing is regulated. When the frequency of regulation is high, the security level is raised to a higher security level than the current security level, and when the frequency is low, the security level is lowered to a lower security level than the current security level.

  For example, when copying an original, as shown in FIG. 4, the image reading unit 2 reads an image of the original and inputs image data (S1). The specific image determination unit 64 detects a specific image from the image data input from the image reading unit 2 (S2). If the specific image is not detected, the instructed process, here, printing is executed (S10).

  When a specific image is detected, if the number of specific images exceeds a threshold value, the control unit 7 restricts processing and prohibits copying (S3). Then, the number of times of regulation is counted (S4). If the number of specific images does not exceed the threshold value, the document is copied.

  The control unit 7 accumulates the number of times of regulation for a predetermined period such as one week or one month. Then, when the predetermined period has elapsed, it is determined whether or not the number of times of regulation exceeds a predetermined number of times (S6). When the number of times of regulation in a predetermined period exceeds the predetermined number, the frequency of regulation is high. The control unit 7 determines that unauthorized use is frequently performed, and raises the security level (S7).

  That is, the control unit 7 lowers the detection criterion for the specific image. Thereby, the detection accuracy of the specific image is improved, and the specific image can be reliably detected. For example, the threshold value is lowered. When erroneous detection that cannot accurately determine a specific image due to dirt or the like occurs, the number of detected specific images decreases. However, since the threshold value is lowered, the number of specific images exceeds the threshold value, and processing is restricted.

  In addition, the similar range of the specific image is widened. When detecting a specific image, the range of detectable image density is expanded. Even a thin specific image is detected as one specific image, and the number of specific images that can be detected increases. Even if the number of specific images does not exceed the threshold if the detection criterion is before the change, the number of specific images exceeds the threshold if the detection criterion is after the change.

  By expanding the range of the angle of the specific image that can be detected, the similarity range of the specific image is widened. Even if the angle of the specific image is not 45 degrees, it is regarded as the specific image even if the angles are different as long as they have the same inclined pattern. By detecting a misleading similar image as a specific image, the number of specific images detected increases, and the number of specific images exceeds the threshold.

  Or the control part 7 changes the addition conditions of a specific image. This makes it easier to detect the specific image when the image data is input after the specific image is added and the image data is output. For example, the number of specific images to be added is increased. As a result, the image data with the increased number of specific images is printed and output, and a document including many specific images is created. When this original is read, the number of specific images that can be detected increases, and the threshold value is reliably exceeded. Further, the image density of the specific image is increased. Thereby, a specific image darker than usual is output. When a document including the specific image is read, the specific image can be definitely detected. Misdetection of specific images is eliminated, and the number of specific images reliably exceeds the threshold.

  As described above, it is possible to improve the detection accuracy of specific images and reduce false detections by changing either or both of changing the detection criteria for specific images and changing additional conditions. As a result, the specific image can be detected with certainty, and the unauthorized use can be suppressed by increasing the security level.

  On the other hand, when the number of times of regulation in the predetermined period does not exceed the predetermined number of times, the frequency of regulation is low. The control unit 7 determines that the possibility of unauthorized use is low, and lowers the security level (S8). A change opposite to the above is performed, and the detection accuracy of the specific image is reduced, or additional conditions are relaxed. As a result, the number of detected specific images is reduced and the threshold value is not exceeded. It is possible to eliminate malfunctions such as processing being restricted despite unauthorized use. Since unreasonable regulation is not performed, convenience for the user can be improved.

  When the number of times of regulation is equal to the predetermined number of times, the control unit 7 does not change the security level (S9). That is, the specific image detection criterion and the specific image addition condition are not changed.

  By the way, unauthorized use may be concentrated. In this case, the number of times of regulation reaches the predetermined number before the predetermined period elapses, and the frequency of regulation becomes abnormally high. Therefore, the control unit 7 increases the security level when the number of times of regulation reaches the predetermined number before the predetermined period elapses.

  Alternatively, in order to immediately respond to an abnormal increase in the frequency of regulation, the control unit 7 determines that the usage is abnormal when the number of times of regulation does not exceed a predetermined number, but the number of times of regulation in a certain time exceeds a certain number of times, Increase security level. In this way, when an abnormal use is made, the security level can be immediately raised, and unauthorized use thereafter can be prevented.

  As described above, when the frequency of regulation increases, the security level is raised. Thereafter, the specific image is detected. After the security level is changed, when the frequency of regulation in the predetermined period becomes low, the control unit determines that unauthorized use is not performed, and restores the security level. As a result, malfunctions can be eliminated and user convenience can be maintained.

  In addition, this invention is not limited to the said embodiment, Of course, many corrections and changes can be added to the said embodiment within the scope of the present invention. When changing the security level, in addition to changing the detection criteria and additional conditions for the specific image, the user authentication and processing restriction ranges may be changed.

  As for user authentication, if the frequency of regulations is high, the security level is raised by setting the user authentication to none. If authentication has already been performed, the security level is raised by performing multiple authentications from one authentication. In the case of lowering the security level, authentication is changed from present to absent, or a plurality of authentications are set as one authentication. The third party performs unauthorized use, but the third party is not authenticated. Therefore, a third party cannot use the image processing apparatus by increasing the security level by strengthening authentication.

  Regarding the process restriction range, when the security level is increased, the process restriction range is widened. For example, when the restriction is only copy prohibition, it extends to data transmission prohibition and filing prohibition.

  When performing user authentication, the user to be used can be specified. Therefore, a security level is set for each user. When only a specific user is frequently regulated, the security level for the user is increased. Since the security level of other users is not changed, it is possible to maintain user convenience while improving security.

Control block diagram of image processing apparatus of the present invention The figure which shows the schematic whole structure of an image processing apparatus. Figure showing a document with specific images arranged and enlarged specific images Flow chart showing the procedure for determining the security level

Explanation of symbols

2 Image reading unit 3 Image forming unit 4 Storage unit 5 Communication unit 6 Operation panel 7 Control unit 63 Specific image adding unit 64 Specific image determining unit

Claims (5)

An input means for inputting image data, a security level for image data protection, a detection means for detecting a specific image in the image data in accordance with the determined security level, and a security level when the specific image is detected Therefore , the control unit counts the number of times of regulation in a predetermined period, and determines that the frequency of regulation is high when the number of times of regulation exceeds a predetermined number of times. When the number of times of regulation does not exceed the predetermined number of times, it is judged that the frequency of regulation is low, the current security level is changed according to the frequency of regulating the process, and the control means judges that the frequency of regulation is high. An image processing apparatus characterized by raising a current security level by lowering a detection criterion for a specific image. The control means determines whether or not the number of specific images in the image data exceeds a threshold value. When the threshold value is exceeded, the control means regulates processing. When the control means determines that the frequency of regulation is high , the control means sets the threshold value. 2. The image processing apparatus according to claim 1, wherein the detection criterion of the specific image is lowered by lowering or widening a similar range of the specific image. 3. The image processing apparatus according to claim 1, wherein the control means lowers the current security level when determining that the frequency of the regulation is low. Control means, when restricting the number of times before the lapse of a predetermined period exceeds a predetermined number of times, the image processing apparatus according to claim 1, characterized in that to raise the security level is. Control means is restricted number does not exceed the predetermined number of times, a predetermined when the time restriction number of exceeds a predetermined number of times, according to claim 4 Symbol mounting image processing apparatus, characterized in that raising the security level of the current.

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