JP2011199441A - Image processing device, program, and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent forgery of special originals such as paper money and securities in an image processing device that processes inputted image data so as to accumulate the image data once in a storage device and to reutilize the accumulated image data.SOLUTION: An image-data processing device 2 processes image data to be accumulated in HDD 4. The image-data processing device 2 executes detection of a special original by an internal special-original detecting part so as to record the result in a header of output-image data. An image-data processing device 17 applies processing for the output purpose to the image data accumulated in the HDD 4. The image data processing device 17 controls operation of the internal special-original detecting part according to the special-original detection result recorded in the header of the image data to be processed.

Description

  The present invention relates to an image processing apparatus that processes image data input by a document reading apparatus or the like, temporarily stores the image data in a storage device, and reuses the stored image data. Related to anti-counterfeiting technology for special manuscripts such as securities.

  Due to the dramatic improvement in the performance of image reading devices and image forming devices, there are increasing opportunities for counterfeiting of special manuscripts such as banknotes and securities that cannot be forged. Even in an image processing apparatus that processes image data input by a document reading device or the like, temporarily stores it in a storage device, and processes and outputs the stored image data, forgery of a special document is an important issue. Yes.

  Regarding the prevention of counterfeiting of a special manuscript, Patent Document 1 discloses a terminal device that performs special manuscript detection on image data input from the outside and prohibits external output of the image data when it is determined to be a special manuscript. Is disclosed.

  An object of the present invention is to reliably prevent forgery of special manuscripts such as banknotes and securities in an image processing apparatus that processes input image data, temporarily stores it in a storage device, and reuses the stored image data. There is to be able to do it.

The invention described in claim 1
Storage means for accumulating images;
First image data processing means for processing image data before being stored in the storage means;
An image processing apparatus comprising: second image data processing means for performing processing for output purposes on the image data stored in the storage means;
The first image data processing unit includes a first special document detection unit for detecting a special document that is not allowed to be forged, and a detection result of the first special document detection unit is output as a header of image data to be output. Recorded as part of the information,
The second image data processing means includes second special document detection means for detecting a special document that is not allowed to be forged, and is recorded as a part of header information of image data to be processed. The image processing apparatus includes a control unit that controls the operation of the second special document detection unit in accordance with a detection result of the special document detection unit.

According to a second aspect of the present invention, in the image processing apparatus according to the first aspect of the present invention,
The detection result of the first special document detection means is “detection” when a special document is detected, “non-detection” when a special document is not detected, or “gray” where there is a high possibility of being a special document. The first image data processing means performs a specific filtering process on the image data when the detection result of the first special document detection means is “gray”.

According to a third aspect of the present invention, in the image processing apparatus according to the second aspect of the present invention,
The first image data processing means outputs image data for outputting a filter setting for specific filter processing applied to the image data when the detection result by the first special document detection means is “gray”. As part of the header information
In the second image data processing means, when “gray” and a filter setting are recorded as a part of header information of the image data to be processed, the control means performs the second image data processing according to the filter setting. The detection reference of the special document detection means is set.

According to a fourth aspect of the present invention, in the image processing apparatus of the first aspect of the present invention,
The detection result of the first special document detection means is “detection” when a special document is detected, “non-detection” when a special document is not detected, or “gray” where there is a high possibility of being a special document. The first image data processing means applies a specific filter process to the image data when the detection result of the first special document detection means is “gray”, and the image subjected to the specific filter process is applied. The data is added to the image data that is not subjected to the specific filtering process as incidental information and output,
In the second image data processing means, when “gray” is recorded as part of the header information of the image data to be processed, the image data to be processed by the second special document detection means and its accompanying Special document detection is performed for each piece of image data added as information, and the detection result is determined by combining the detection results.

According to a fifth aspect of the present invention, in the image processing apparatus according to the fourth aspect of the present invention,
The first image data processing unit outputs image data for outputting a filter setting for specific filter processing applied to the image data when the detection result of the first special document detection unit is “gray”. As part of the header information
In the second image data processing means, when “gray” and the filter setting are recorded as part of the header information of the image data to be processed, the control means performs processing according to the filter setting. A detection reference of the second special document detection unit is set for each of the image data and the image data added as the accompanying information.

The invention according to claim 6 is the image processing apparatus according to claim 4 or 5, wherein
The first image data processing unit is configured to detect the first special document detection unit of the image data subjected to the specific filter processing when the detection result of the first special document detection unit is “gray”. Thus, only the data of the area determined as “gray” is added to the image data that is not subjected to the specific filter processing and is output as supplementary information.

The invention according to claim 7 is the image processing apparatus according to any one of claims 1 to 6,
The first image data processing means records a history of the image data passing through the first image data processing means as a part of header information of the output image data,
In the second image data processing means, when the history is not recorded as header information of the image data to be processed, the control means sets the second special document detection means to a state in which the special document is detected. It is characterized by doing.

  An eighth aspect of the invention is a program that causes a computer to function as the first and second image data processing means and the storage means of the image processing apparatus according to any one of the first to seventh aspects of the invention.

  According to a ninth aspect of the present invention, a computer in which a program that causes a computer to function as the first and second image data processing means and the storage means of the image processing apparatus according to any one of the first to seventh aspects is read. It is a possible recording medium.

  According to the first to seventh aspects of the present invention, special document detection is appropriately performed at the stage of pre-storage processing for images and the post-storage processing for output purposes, so that forgery of special documents can be reliably prevented. According to the seventh aspect of the present invention, it is possible to prevent forgery of a special document even when unauthorized storage image data is falsified due to physical exchange of storage means or the like. According to the eighth and ninth aspects of the present invention, it is possible to easily achieve the image processing apparatus according to the first to seventh aspects of the invention using a computer.

1 is an overall configuration diagram of a digital image processing apparatus according to an embodiment of the present invention. It is a block diagram for demonstrating the Example of the image data processing apparatus for a pre-storage process. It is a block diagram for demonstrating the Example of the image data processing apparatus for a pre-storage process. It is a block diagram for demonstrating the Example of the image data processing apparatus for a pre-storage process. It is a block diagram for demonstrating the Example of the image data processing apparatus for the accumulation | storage post-process for the output purpose. It is a figure for demonstrating the special threshold value detection sensitivity characteristic with respect to various image types, and the determination threshold value as a detection reference. It is explanatory drawing of the confidential management of stored image data.

  FIG. 1 is an overall configuration diagram of a digital image processing apparatus (MFP) according to an embodiment of the present invention. The components of the digital image processing apparatus 100 will be described sequentially.

  The reading device 1 is a device that scans a document to acquire density information of the document, and generates and outputs, for example, digital image data of 8 bits for each RGB from the density information.

  The image data processing device 2 performs pre-storage processing on the image data input from the reading device 1, or the image data from the PC 15 through the external I / F device 11 or the memory 6 or the image data from the external medium 16. The image file output from this device is stored in the HDD 4. The image data processing device 2 includes means for detecting a special manuscript that makes it illegal to forge banknotes or securities.

  The image data processing unit 17 is a device that decompresses the compressed image data of the image file read from the HDD 4 and performs post-storage processing for output purposes. The image file output from this device is stored in the HDD 4. The image data processing device 17 is also provided with means for detecting special originals such as banknotes and securities.

  The HDD 4 is a storage device for storing image data and the like. The bus control device 3 is a device for exchanging various data such as image data and control commands necessary in the digital image processing device 100. The CPU 5 is a microprocessor that controls the entire control of the digital image processing apparatus 100. The memory 6 is a volatile memory used for temporary storage of programs and intermediate processing data when the CPU 5 controls the digital image processing apparatus 100. The plotter I / F device 7 is a device that receives CMYK image data transferred from the CPU 5 and outputs it to the plotter device 8. The plotter device 8 is a device that outputs the CMYK image data input from the plotter I / F device 7 onto a transfer sheet by an electrophotographic process using a laser beam. S. B. (South Bridge) 12 is a general-purpose circuit of the bus bridge function. The ROM 13 is a non-volatile memory in which a program for the CPU 5 to control the digital image processing apparatus 100 is stored. The operation display device 9 is a portion that performs an interface between the digital image processing device 100 and a user, and is composed of an LCD (Liquid Crystal Display) and a key switch. This device detects switch input. The digital image processing apparatus 100 exchanges image data with the FAX 14 outside the apparatus via the telephone line and the line I / F device 10. The digital image processing apparatus 100 performs various controls and image data input / output with the external media 16 such as the PC 15 and the SD card outside the apparatus via the network (Ethernet) and the external I / F device 11.

Hereinafter, the image data processing devices 2 and 17 related to the main features of the present invention will be described in detail with reference to some embodiments.
<Example 1>
FIG. 2 is a block diagram for explaining the configuration of the image data processing apparatus 2 according to the first embodiment. In the image data processing device 2, the scanner γ conversion unit 21 performs γ conversion on, for example, RGB 8-bit image data input from the reading device 1 or the like, and converts gradation characteristics from reflectance linearity to density linearity. It is means to do. The scaling processing unit 22 is a means for performing scaling processing to the resolution designated by the operation display device 9 on the image data converted into the density linear gradation characteristics. The filter processing unit 23 is a means for performing filter processing such as emphasizing the character portion and smoothing the pattern portion. The color correction unit 24 is a unit that converts the RGB image data that has passed through the filter processing unit 23 into a device-independent color space such as AdobeRGB or sRGB. The gradation correction unit 25 is a device that performs processing for changing the output characteristics of the image data corrected by the color correction unit 24. For example, when the operation display device 9 is instructed to increase the contrast, Processing is performed to increase the gradation change amount of the output gradation with respect to the gradation. The gradation correction unit 25 is also means for applying special gradation correction to the image data so that the image is filled when a special document is detected. The compression processing unit 26 performs a compression process on the image data input from the gradation correction unit 25 in accordance with the resolution specified by the operation display device 9 or the like, and outputs an image file of the compressed image data. This image file is stored in the HDD 4. The compression processing in the compression processing unit 26 may be performed by a known compression method.

  The special manuscript detection unit 27 is a means for detecting special manuscripts such as banknotes and securities, for example, pattern matching between an image of a specific special manuscript and an input image, and the distance (difference) between the two images. If it is equal to or less than the determination threshold, it is determined that the document is a special document (special document detection). If the determination threshold is exceeded, it is determined that the document is not a special document (special document non-detection). In this case, the sensitivity of the special document increases as the judgment threshold used as a special document detection criterion increases, and the detection of the special document is less likely to occur. However, on the other hand, an image that is not a special document is erroneously detected as a special document. It becomes easy to do. Conversely, as the determination threshold value is decreased, the sensitivity of detection of a special document decreases, and an image that is not a special document is mistakenly detected as a special document, but on the other hand, detection of a special document is more likely to occur. Note that there are a reading device 1, a PC 15, and an external medium 16 as sources of input image data, and there are differences in input characteristics. Therefore, the detection standard for special originals (here, the determination threshold for the distance between images) differs depending on the source. It is also possible to

  The detection result of the special document detection unit 27 is given to the gradation correction unit 25. In the case of special document detection, a special gradation correction that prevents normal image reproduction, such as filling the image in the gradation correction unit 25. Is applied to the image data.

  The compression processing unit 26 records a history that the image data has passed through the image data processing device 2 and a special document detection result as part of the header information of the output image file.

  FIG. 5 is a block diagram for explaining the configuration of the image data processing apparatus 17 according to the first embodiment. The processing by the image data processing device 17 corresponds to post-accumulation processing for image output purposes.

  In the image data processing device 17, the decompression processing unit 31 is a unit that performs a process of decompressing the compressed data of the image file read from the HDD 4 for output purposes. The scaling processing unit 32 is a unit that performs scaling processing for converting the RGB image data expanded by the expansion processing unit 31 to the resolution specified by the operation display device 9. The filter processing unit 33 is a unit that performs filter processing, such as emphasizing a character part and smoothing a pattern part, on the image data processed by the scaling processing unit 32. The color correction unit 34 is a unit that performs color space conversion corresponding to the output color space on the RGB image data processed by the filter processing unit 33. For example, for paper output purposes, the CMYK space corresponding to the output plotter is used. If it is a distribution purpose, it is converted into the color space (sRGB, AdobeRGB) of the output destination monitor. The gradation correction unit 35 is a means for performing gradation correction processing on the image data processed by the color correction unit 34. For example, when the operation display device 9 is instructed to increase the contrast, the gradation correction unit 35 adjusts the input gradation. On the other hand, correction is performed so that the gradation change amount of the output gradation increases. The gradation processing unit 36 is means for performing screen processing such as a dither method or an error diffusion method on the image data after gradation correction in accordance with output conditions. The compression processing unit 37 is means for compressing the processed image data by the gradation processing unit 36 in accordance with the resolution designated by the operation display device 9 or the like and outputting an image file of the compressed image data. This image file is stored in the HDD 4. In addition, the compression process in the compression process part 37 can be performed by a well-known method.

  The special manuscript detection unit 38 is a means for detecting special manuscripts such as banknotes and securities, and performs, for example, pattern matching between an image of a specific special manuscript and an input image, and the distance between both images is equal to or less than a determination threshold. If it exceeds the determination threshold, it is determined that the document is not a special document (special document non-detection). In this case, the sensitivity of the special document increases as the judgment threshold used as a special document detection criterion increases, and the detection of the special document is less likely to occur. However, on the other hand, an image that is not a special document is erroneously detected as a special document. It becomes easy to do. Conversely, as the determination threshold value is decreased, the sensitivity of detection of a special document decreases, and an image that is not a special document is mistakenly detected as a special document, but on the other hand, detection of a special document is more likely to occur. The detection result of the special document detection unit 38 is given to the gradation correction unit 35. When the detection result is “special document detection”, the special correction that prevents normal image reproduction, such as filling the image with the gradation correction unit 35, is performed. Correct gradation correction.

  The special document detection control unit 39 is means for acquiring header information of an image file to be output from the decompression processing unit 31 and controlling the operation of the special document detection unit 38 based on the information. In other words, when the special document detection result before accumulation recorded in the header is “special document non-detection”, the special document detection control unit 39 causes the special document detection unit 38 to execute special document detection. In this way, by performing the special document detection before and after the image data is accumulated, it is possible to detect the special document that has failed to be detected before the accumulation and to more reliably prevent forgery. When the special document detection result before accumulation is “special document detection”, the special document detection control unit 39 suppresses the operation of the special document detection unit 38. Since the special document detection operation is suppressed in this way, the special gradation correction is not performed by the gradation correction unit 35, but the special gradation correction is performed on the image data in the image data processing device 2 before accumulation. Therefore, counterfeiting of special manuscripts is prevented.

  If the history of being stored via the image data processing device 2 is not recorded in the header of the image file, the image file is illegally stored or altered by physical replacement of the HDD 4 or electrical forced conversion. It is highly possible that Therefore, when the transit history of the image data processing device 2 is not recorded, the special document detection control unit 39 sets the special document detection unit 38 to a state where the special document is detected (the detection result is forcibly set to “detection”). The tone correction unit 35 performs special tone correction that prevents normal image reproduction, such as filling an image. Thereby, normal image reproduction of special manuscript image data that has been illegally accumulated by replacement of the HDD 4 or the like can be prevented, and forgery of the special manuscript can be prevented.

<Example 2>
As in the first embodiment, the image data processing device 2 performs two types of determinations as to whether or not the document is a special document before accumulation, and the image data is painted when the document is determined to be a special document. In a configuration that performs smooth gradation correction, if a special document is erroneously detected, the normal reproduction of an image becomes impossible, which has a great effect. However, when handling images with different input conditions, such as input images from external media with opaque characteristics, it is not easy to perform special document detection without false detection in one special document detection process (setting detection criteria). Is difficult).

  In the second embodiment, special pre-storage processing is performed based on the fact that both the image data processing device 2 for pre-storage processing and the image data processing device 17 for post-storage processing for output are provided with special document detection means. The document detection unit 27 performs three types of determination: a special document (special document detection), a non-special document (special document non-detection), and a possibility of a special document (gray). Accordingly, it is possible to greatly reduce the false detection of a non-special manuscript as a special manuscript at the pre-storage stage. Then, the special document detection unit 38 in the post-storage process performs a special document detection process on the image data determined to be “gray” in the pre-storage process, thereby determining whether the document is a special document with higher accuracy. Can be determined.

  FIG. 3 is a block diagram for explaining the configuration of the image data 2 according to the second embodiment. The detection result of the special document detection unit 27 is also given to the filter processing unit 23.

  In the second embodiment, as described above, the special manuscript detection unit 27 performs “special manuscript detection” which is a special manuscript image, “special manuscript non-detection” which is not a special manuscript image, and a special manuscript image. Three types of determination “gray” with a small possibility are made. For example, pattern matching between an image of a specific special document and an input image is performed. If the distance (difference) between the two images is equal to or smaller than the first determination threshold th1, “special document detection” is performed, and the distance is determined as the second determination. If the threshold value th2 (th2> th1) is exceeded, “special document non-detection” is determined, and if the distance is greater than the first determination threshold value and less than the second determination threshold value th2, “gray” is determined. As described above, the two determination thresholds th1 and th2 are used as the detection reference for the special document.

  When it is determined as “gray”, the filter processing unit 23 performs an additional filter process on the image data after the scaling process in addition to the normal filter process. The additional filter processing peculiar to the case of “gray” is to make it easy to increase the accuracy of detecting a special document by the special document detection unit 38 in the image data processing apparatus 17 for post-storage processing. In other words, device sensitivity of input conditions is eliminated as much as possible, such as leveling of RGB sensitivity variations for each input device of image data, and the range of RGB signals is expanded or a specific hue is emphasized.

  The gradation correction unit 25 performs a special gradation correction process that fills an image only when a special document is detected. The compression processing unit 26 records a special document detection result and a history that the image data has passed through the image data processing device 2 for pre-storage processing in the header of the output image file. When the special document detection result is “gray”, the filter setting for additional filter processing in the filter processing unit 23 is also recorded in the header. The output image file is stored in the HDD 4.

  Also in the second embodiment, the block configuration of the image data processing device 17 for post-storage processing for output purposes is as shown in FIG. The special document detection control unit 39 acquires the header information of the image file to be output from the decompression processing unit 31, and the special document detection result before accumulation recorded in the header is “special document non-detection” and “ In the case of “gray”, the special document detection unit 38 executes special document detection. For example, the special original detection unit 38 performs pattern matching between an image of a specific special original and an input image, and determines that the original is a special original if the distance (difference) between the two images is equal to or less than a determination threshold (special). Document detection), if the determination threshold is exceeded, it is determined that the document is not a special document (special document non-detection). In this case, different determination threshold values can be set depending on whether the special document detection result in the pre-storage process is “special document non-detection” or “gray”. When a special document is detected, special gradation correction is performed such that the gradation correction unit 35 fills the image in order to prevent forgery of the special document.

  If the special document detection result in the pre-storage process is “gray”, it is determined as “gray” by setting a determination threshold value that is a detection criterion for the special document according to the filter setting recorded as the header information. The accuracy of special document detection for the accumulated image data can be further improved.

  Similarly to the first embodiment, when the history through the image data processing device 2 is not recorded before the storage as the header information of the stored image data, the HDD 4 is physically exchanged and the electrical forced conversion is performed. Since there is a high possibility that the image file has been illegally stored or falsified, the special document detection control unit 39 forcibly sets the detection result of the special document detection unit 38 to “special document detection”. By doing this, the tone correction unit 35 performs a special tone correction that fills the image, prevents normal image reproduction of special manuscript image data illegally accumulated by replacing the HDD 4, etc. Prevent counterfeiting.

<Example 3>
FIG. 4 is a block diagram for explaining the configuration of the image data processing apparatus 2 according to the third embodiment. In FIG. 4, an incidental information adding unit 28 is added.

  The detection result of the special document detection unit 27 in the image data processing device 2 is any one of “special document detection”, “special document non-detection”, and “gray” as in the second embodiment. In the case of “gray”, as in the second embodiment, the filter processing unit 23 performs additional filter processing (specific filter processing) in addition to normal filter processing. When the special document detection result is “gray”, image data that has been subjected only to normal filter processing by the filter processing unit 23 (referred to as image data B for convenience) and additional filter processing are performed in addition to the normal filter processing. The image data (referred to as image data A for convenience) is sent to the compression processing unit 26 via the color correction unit 24 and the gradation correction unit 25. The accompanying information adding unit 28 causes the compression processing unit 26 to add the compressed data of the image data A as the accompanying information to the compressed data of the image data B, and collects and outputs them as one image file. This image file is stored in the HDD 4. In the header of the image file, as in the second embodiment, the special document detection result, the filter setting for the additional filter processing in “gray”, and the history of being accumulated via the image data processing device 2 Is recorded.

  When the detection result of the special document detection unit 27 is “special document non-detection”, only normal filter processing is performed by the filter processing unit 23, so that additional information as in the case of “gray” is not added. An image file containing compressed data of only one type of image data is output from the compression processing unit 26. When the special document detection result is “special document detection”, normal filter processing is performed by the filter processing unit 23, so that additional information is not added as in the case of “gray”, and the tone correction unit 25. The compression processing unit 26 outputs an image file containing compressed data of only one type of image data that has been subjected to special gradation correction that fills the image.

  The image data processing device 17 for post-storage processing for output purposes has the same block configuration as that shown in FIG. Differences from the second embodiment are as follows.

  A case will be described in which the special document detection result recorded in the header of the input image file is “gray”. In this case, the input image file stores the image data B and the compressed data of the image data B, and each is decompressed by the decompression processing unit 31. Image data B is the only image data processed by the scaling unit 32 and below. The special document processing unit 38 receives the decompressed image data A and image data B. The special document detection control unit 39 causes the special document detection unit 38 to perform special document detection for each of the image data B and the image data A. The special document detection for the image data A and B is performed by, for example, performing pattern matching between an image of a specific special document and an input image (A or B), and special if the distance (difference) between the images is equal to or less than a determination threshold. It is determined that the document is a document (special document detection), and if the determination threshold is exceeded, it is determined that the document is not a special document (special document non-detection). The special document detection unit 38 combines the detection result for the image data A and the detection result for the image data B, and determines the final detection result. Since this method is used, it is possible to detect a special document with high accuracy for the image data set to “gray”. When the final special document detection result is “special document detection”, the gradation correction unit 35 performs special gradation correction such that the image is filled.

  When the special document detection result before accumulation recorded in the header of the input image file is “special document non-detection”, only compressed data of one type of image data (image data B) is stored in the image file. ing. This image data is decompressed and processed by the scaling processing unit 32 and the subsequent processing. The special document detection control unit 39 causes the special document detection unit 38 to execute a special document detection operation for the image data. When the detection result is “special document detection”, the tone correction unit 35 performs special tone correction such that the image is filled.

  When the special document detection result before accumulation recorded in the header is “special document detection”, the special document detection control unit 39 suppresses the operation of the special document detection unit 38. Since the special document detection operation is suppressed in this way, the special gradation correction is not performed by the gradation correction unit 35, but the special gradation correction is performed on the image data in the image data processing device 2 before accumulation. Therefore, counterfeiting of special manuscripts is prevented.

  When the history that the image data processing apparatus 2 has accumulated is not recorded in the header, the image file is illegally accumulated or falsified due to physical replacement of the HDD 4 or electrical forced conversion Is likely. Therefore, when the route history of the image data processing device 2 is not recorded, the special document detection control unit 39 forcibly sets the detection result of the special document detection unit 38 to “special document detection”, thereby correcting the gradation. A special gradation correction that prevents normal image reproduction, such as filling an image in the unit 35, is performed. Thereby, normal image reproduction of special manuscript image data that has been illegally accumulated by replacement of the HDD 4 or the like can be prevented, and forgery of the special manuscript can be prevented. However, it is also possible to perform control to suppress the output of the image file, and such an aspect is also included in the present invention.

  FIG. 6 shows special document detection sensitivity characteristics for various image types as curves. The horizontal axis indicates the image type, and the vertical axis indicates the distance (difference) between each type of image and the special document image. The distance corresponding to the detection sensitivity is used as a determination threshold, and if the distance from the special document image is below the determination threshold, it may be determined that the document is not a special document. If the distance is above the determination threshold, the document is determined to be a special document. You can do it. As shown in the detection sensitivity characteristic curve, the detection sensitivity varies depending on the type of image. Since it is not easy to set determination threshold values corresponding to individual detection sensitivities for all image types, the determination threshold th1 is set to, for example, a constant sensitivity TH1 shown in FIG. If the determination threshold th1 is decreased from TH1 (decrease in sensitivity), detection omissions are likely to occur depending on the image type. Conversely, if the determination threshold th1 is increased from TH1 (sensitivity is increased), a special document is used even though it is not a special document. Misdetection to determine a document is likely to occur.

  In order to prevent forgery of a special document, omission of detection of a special document is not allowed. Therefore, in the case of an image processing apparatus configured not to accumulate images, the determination threshold th1 is set so that there is no omission of detection rather than erroneous detection. Must be. However, in the case of the present invention in which special document detection is possible in both pre-accumulation processing and post-storage processing, detection omission in the pre-storage processing can be tolerated to some extent. The determination threshold th1 can be set to a sensitivity TH1 close to the sensitivity lower limit of the sensitivity characteristic curve. Then, the determination threshold th2 is set to another sensitivity TH2 close to the sensitivity upper limit of the sensitivity characteristic curve, and when the distance between the input image and the special document image is between the determination threshold th1 and the determination threshold th2, it is determined as “gray”. When the distance is equal to or less than the determination threshold th1, the document is determined to be a special document, and when the distance exceeds the determination threshold th2, the document is determined not to be a special document.

  When the special document detection unit 27 determines “gray”, the filter processing unit 23 performs additional filter processing. The filter setting for this additional filter processing is similar to that in the second embodiment. In addition to the difference in input conditions and the like, it is determined in consideration of the difference ΔS (FIG. 6) between the detection sensitivity of the image type of the image data and the determination threshold th1 = TH1. Since the image type and its detection sensitivity are known from the characteristics of the input image data, ΔS can be obtained.

  In the post-accumulation image data processing device 17, when the special document detection result recorded in the header of the image file is “gray”, the special document detection control unit 39 performs image data A on which additional filter processing has been performed. And a special document detection threshold for image data B that has not been subjected to additional filter processing are set as filter settings for additional filter processing recorded in the header of the input image file. Based on the determination and setting in the special document detection unit 37, the special document detection unit 37 causes the image data A and the image data B to be detected with high accuracy.

The operation when the special document detection result recorded in the header of the input image file is “special document detection” or “special document non-detection”, and the history that the image data processing device 2 has been passed are recorded in the header. If not, the operation is the same as in the second embodiment.
<Example 4>
The image data processing apparatus 2 according to the fourth embodiment has the configuration shown in FIG. 4 as in the third embodiment. The image data processing device 17 according to the fourth embodiment has the same configuration as that of the third embodiment.

  The difference from the third embodiment is that, in the image data processing apparatus 2, when the special document determination unit 27 determines “gray”, the entire region of the image data A that has been subjected to the additional filter processing by the filter processing unit 23. The data is not added to the image data B as supplementary information, but only the data of the area determined as “gray” of the image data A is attached to the image data B. That is, the area determined as “gray” by the special document detection unit 27 is designated to the auxiliary information adding unit 28, and the auxiliary information adding unit 28 in the compression processing unit 26 receives the image data A input from the gradation correcting unit 25. Control is performed to add only the data in the designated area to the image data B as image data A. In this way, an increase in the size of the image file due to the addition of the image data A can be suppressed, the load of the transfer processing of the image file can be reduced, and the expansion processing unit in the image data processing device 17 31 and the processing load on the image data A in the special document detection unit 38 can be reduced.

  In the embodiment of the present invention described above, the storage space of the HDD 4 that is a storage device for storing image data is divided into a normal storage area 72 and a confidential storage area 71 as shown in FIG. Control is performed so that the image data stored in the confidential storage area 71 passes through the image data processing device 17 for processing for output purposes. If control is performed so that image data whose special document detection result in the pre-storage image data processing apparatus 2 is “detected” or “gray” is stored only in the confidential storage area 71, the image of the special document is stored. Normal reproduction of image data that is suspected of being data or a special manuscript is blocked, and it has a great effect in preventing forgery of the special manuscript. Such embodiments are also encompassed by the present invention.

  In the above description, the image data is compressed and stored. However, the present invention includes an aspect in which the image data is stored in an uncompressed state.

  In addition, a program that causes a computer to function as a component (image data processing devices 2 and 17, HDD 4, etc.) of the image processing device according to the present invention, a semiconductor storage element on which such a program is recorded, a magnetic disk, an optical disk, a magneto-optical Various recording (storage) media readable by a computer, such as a disk, are also included in the present invention.

DESCRIPTION OF SYMBOLS 1 Reading apparatus 2 Image data processing apparatus 4 for pre-storage processing 4 HDD
17 Image data processing device 23 for post-storage processing for output purposes Filter processing unit 25 Gradation correction unit 26 Compression processing unit 27 Special document detection unit 28 Attached information addition unit 31 Decompression processing unit 35 Gradation correction unit 38 Special document detection 39 Special document detection controller 71 Confidential storage area

JP-A-10-198838 JP 2000-232576 A

Claims (9)

Storage means for accumulating images;
First image data processing means for processing image data before being stored in the storage means;
An image processing apparatus comprising: second image data processing means for performing processing for output purposes on the image data stored in the storage means;
The first image data processing unit includes a first special document detection unit for detecting a special document that is not allowed to be forged, and a detection result of the first special document detection unit is output as a header of image data to be output. Recorded as part of the information,
The second image data processing means includes second special document detection means for detecting a special document that is not allowed to be forged, and is recorded as a part of header information of image data to be processed. An image processing apparatus comprising: a control unit that controls an operation of the second special document detection unit according to a detection result by the special document detection unit.   The detection result of the first special document detection means is “detection” when a special document is detected, “non-detection” when a special document is not detected, or “gray” where there is a high possibility of being a special document. 2. The image data processing unit according to claim 1, wherein the first image data processing unit performs a specific filtering process on the image data when the detection result of the first special document detection unit is “gray”. Image processing device. The first image data processing means outputs image data for outputting a filter setting for specific filter processing applied to the image data when the detection result by the first special document detection means is “gray”. As part of the header information
In the second image data processing means, when “gray” and a filter setting are recorded as part of the header information of the image data to be processed, the control means performs the second image data processing according to the filter setting. The image processing apparatus according to claim 2, wherein a detection reference of the special document detection means is set. The detection result of the first special document detection means is “detection” when a special document is detected, “non-detection” when a special document is not detected, or “gray” where there is a high possibility of being a special document. The first image data processing means applies a specific filter process to the image data when the detection result of the first special document detection means is “gray”, and the image subjected to the specific filter process is applied. The data is added to the image data that is not subjected to the specific filtering process as incidental information and output,
In the second image data processing means, when “gray” is recorded as part of the header information of the image data to be processed, the image data to be processed by the second special document detection means and the incidental information thereof The image processing apparatus according to claim 1, wherein special document detection is performed on each of the image data added as, and the detection results are determined by combining the detection results. The first image data processing unit outputs image data for outputting a filter setting for specific filter processing applied to the image data when the detection result of the first special document detection unit is “gray”. As part of the header information
In the second image data processing means, when “gray” and a filter setting are recorded as part of header information of the image data to be processed, the control means performs an image to be processed according to the filter setting. 5. The image processing apparatus according to claim 4, wherein a detection standard of the second special document detection unit is set for each of data and image data added as accompanying information thereof.   The first image data processing unit is configured to detect the first special document detection unit of the image data subjected to the specific filter processing when the detection result of the first special document detection unit is “gray”. 6. The image processing apparatus according to claim 4, wherein only the data of the area determined as “gray” is added to the image data not subjected to the specific filter processing and output as supplementary information. The first image data processing means records a history of the image data passing through the first image data processing device as a part of header information of the output image data,
In the second image data processing means, when the history is not recorded as header information of the image data to be processed, the control means sets the second special document detection means to a state in which the special document is detected. The image processing apparatus according to claim 1, wherein the image processing apparatus is an image processing apparatus.   A program for causing a computer to function as the first and second image data processing means and the storage means of the image processing apparatus according to claim 1.   A computer-readable recording medium in which a program for causing a computer to function as the first and second image data processing means and the storage means of the image processing apparatus according to any one of claims 1 to 7 is recorded.

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