JP4692422B2 - Image processing apparatus and display control method - Google Patents

Description

  The present invention relates to a technique for preventing unauthorized copying of a document image.

  In recent years, copying of documents has become extremely simple due to the widespread use of image forming apparatuses having a copying function, such as personal computers, printers, and copying machines. Under such circumstances, a manuscript that has been granted a copyright or a manuscript that requires prohibition of unauthorized duplication such as “copy prohibited”, “restrict copying”, “confidential”, etc. (hereinafter collectively “confidential manuscript”) Also has a disadvantage that copying is easily performed. Therefore, it is necessary for an image forming apparatus having a copying function to have a function to prevent misuse and duplication of confidential documents.

  For example, in Patent Document 1, copying prohibition information (whether copying is prohibited), copying permission condition information (information for permitting copying when the conditions are met), latent image information (a latent image that floats when copied) In other words, there is disclosed a technology for recording code information such as information on a background copy-forgery-inhibited pattern of image data and restricting users who can make copies.

  Further, in Patent Document 2, when copying a document, code information embedded in the document is read and analyzed prior to copying, and if user restrictions are set by the code information, user authentication is performed. Techniques for performing are disclosed.

JP 2003-280469 A JP 2004-072343 A

  However, when there are a plurality of documents and different authentication information is set for each page, there is a problem that it is difficult to understand the correspondence between the image and the authentication information.

  The present invention has been made in view of the above circumstances, and an image processing apparatus and a display control method capable of displaying a display in which the correspondence between a read image and authentication information set in the image is clear The purpose is to provide.

In order to achieve such an object, an image processing apparatus of the present invention includes an input unit for inputting image data, a detection unit for detecting user restriction information included in the input image data, and a thumbnail image of the input image data. Display control for displaying the thumbnail image and the input request for the user restriction information side by side when the user restriction information is set in the thumbnail image generation means to be generated and the page where the thumbnail image is generated. have a means, the display control means is characterized in that to display the thumbnail images of a plurality of pages and a prompt for the user restriction information in the input order of the input means.
According to the present invention, it is possible to display on the display means such that the correspondence between the read image and the authentication information set in the image becomes clear.

  In the image processing apparatus, the display control unit displays an input request for the user restriction information in a state where the user restriction information cannot be input when the user restriction information is not set on the page where the thumbnail image is generated. Good.

  In the image processing apparatus, the image processing apparatus further includes an authentication unit that compares a match between the user restriction information input according to the user restriction information input request and the user restriction information detected from the image data, and the display control unit includes The thumbnail image of the page that has been successfully authenticated by the authentication means is displayed in a reduced size, the display color of the thumbnail image of the page that has been successfully authenticated is changed, the thumbnail image of the page that has been successfully authenticated is deleted, and the authentication is performed. Any one of the displays indicating that the authentication is completed may be displayed on the thumbnail image of the successful page.

  In the image processing apparatus, when the display control unit is configured to print a plurality of pages of image data input by the input unit on one page, the display control unit receives an input request for the thumbnail images of the plurality of pages and user restriction information. May be displayed collectively on the display means.

  In the image processing apparatus, the display control unit may change a display order of the thumbnail images of a plurality of pages and the input request for the user restriction information according to the size of the image data input by the input unit.

  In the image processing apparatus, the image processing apparatus further includes a separating unit that separates the image data into image data and text data, and the display control unit includes thumbnails of a plurality of pages according to the data amount of the text data included in the image data. The display order of the image and the input request for the user restriction information may be changed.

  In the image processing apparatus, the display control unit may change the display order of the thumbnail images of a plurality of pages and the input request for the user restriction information according to the hue distribution of the image data.

The display control method of the present invention includes a step of inputting image data, a step of detecting user restriction information included in the input image data, a step of generating a thumbnail image of the input image data, and a generation of a thumbnail image and when the user restriction information in the pages has been set, and the thumbnail images, possess a step of displaying on the display unit side by side and input request of the user restriction information, the step of the display has a plurality of pages The thumbnail images and the user restriction information input request are displayed in the input order of the input step.
According to the present invention, it is possible to display on the display means such that the correspondence between the read image and the authentication information set in the image becomes clear.

  According to the present invention, it is possible to display such that the correspondence between the read image and the authentication information set in the image is clear.

  Preferred embodiments of the present invention will be described with reference to the accompanying drawings.

First, the detailed configuration of the present embodiment will be described with reference to FIG.
The image forming apparatus 1 according to the present exemplary embodiment includes a scanner unit 2, an image processing unit 3, an accumulation / reading processing unit 4, an image storage unit 5, an output unit 6, an embedded information detection unit 7, and a control unit 8. And a user interface unit 9.

  The scanner unit 2 includes an automatic document feeder (hereinafter referred to as “ADF”). The ADF is a document set unit on which a document to be read is stacked, a document discharge unit from which a read document is discharged, and a document set on the document set unit from the document set unit through the platen glass. And a document conveying mechanism that conveys the sheet to the discharge unit.

  The image processing unit 3 performs color correction, color space conversion, screen processing, and the like on the input image data, and outputs the image data after the image processing to the accumulation / read processing unit 4.

  The storage / reading processing unit 4 stores the image data processed by the image processing unit 3 in the image storage unit 5 or reads out the image data designated by the instruction from the control unit 8 from the image storage unit 5 and outputs it. Output to unit 6. The output unit 6 prints out the image data read by the accumulation / read processing unit 4.

  The user interface unit 9 has operation units such as a numeric keypad and operation keys, and a display unit that displays information.

The embedded information detection unit 7 includes a copy prohibition information detection unit 11 and a copy permission condition information detection unit 12. Before describing these function units, code information embedded in the background pattern image of the image will be described first.
Code information embedded in the background pattern image includes the following.
(A) Copy prohibition information (whether or not to prohibit copying)
(B) ... Copy permission condition information (information for permitting copying if the conditions are met)
For example, a personal identification number, a user ID number that permits copying (employee number, etc.), a date and time when copying prohibition is released, a machine number of a copying machine that permits copying (C) ... latent image information (related to a latent image that floats when copied) information)
For example, latent image character string, font type, font size, latent image character string direction (angle), background tint image color

  Here, the background copy-forgery-inhibited pattern image will be described in detail with reference to FIG. The background copy-forgery-inhibited pattern image includes a latent image IP and a background pattern PB that covers the entire surface of the output image O.

  The background pattern PB and the latent image IP are different from each other. However, the output image O is formed with a pattern having the same pixel area and pixel color per unit area so that it can be seen by the human eye as a uniform gray background.

  The latent image IP is composed of finer dots than other portions so that the image appears to the extent that the latent image IP can be identified by human eyes in the copied document.

  The background pattern PB is composed of codes. The code is composed of a condition code CD representing arbitrary code data and a prohibited copy code CP that restricts copying.

  The code is composed of a hatched pattern PS representing arbitrary code data. In the oblique line pattern PS, the one represented by a half line inclined 45 degrees counterclockwise with respect to the scanning direction D represents bit 0 of the code data, and the one inclined 135 degrees represents bit 1 of the code data.

  The forbidden copy code CP is composed of an all diagonal pattern PS representing bit 0 and a bit 1. The forbidden copy code CP is used to determine that a copy is restricted when two or more types of forbidden copy codes CP are detected.

The condition code CD is composed of a synchronization code area AS and a data code area AC.
The synchronous code area AS is a code area in which the outer periphery of a rectangular area of a predetermined size surrounding the data code area AC is composed of a hatched pattern PS1 in which all bits 1 are represented.
In the data code area, a code number, a user ID number permitting copying (employee number, etc.), a date and time for canceling copying prohibition, a machine number of a copying machine permitting copying, and the like are encoded and embedded as a condition code CD. ing.

Next, the copy prohibition information detection unit 11 will be described with reference to FIG. FIG. 3 shows a detailed configuration of the copy prohibition information detection unit 11.
The image data output from the scanner unit 2 is input to the gray scale conversion unit 21 and converted from full color to gray scale. Thereafter, it is binarized by the binarization processing unit 22.

  The binarized image data is input to the noise removal processing unit 23, and noise removal processing is performed. Specifically, a pixel block in which black pixels are connected is obtained, and each pixel of the pixel block whose size (number of connected pixels) is not within a predetermined range is replaced with a white pixel. The predetermined range is set to an appropriate range so that the hatched pattern is not deleted, and other patterns (isolated dot patterns, characters and figures in the document, etc.) are deleted.

  The image data from which noise has been removed is input to the pattern detection processing unit 24, where two types of oblique line pattern detection processing are performed, and the result is output as image data of 2 bits per pixel. Specifically, the pattern shown in FIGS. 4A and 4B is applied at the position of each pixel in the image data, and detection is performed by template matching. Here, when the pattern (A) shown in FIG. 4 is detected, the pixel value 0 is output, and when the pattern (B) shown in FIG. 4 is detected, the pixel value 1 is output and the pattern is not detected. , Pixel value 2 is output.

  The image data output from the pattern detection processing unit 24 is input to the blocking processing unit 25. Here, the block size is set to a size smaller than half the size of the copy prohibition code and the condition code, and is set to a size such that one or more blocks are completely included in the code. The blocking processing unit 25 divides the input image data into blocks of a predetermined size and outputs them to the number calculation unit 26.

  The number calculation unit 26 calculates the number of pixels having a pixel value 0 and the pixel having a pixel value 1 in the block, and outputs the result to the ratio calculation unit 27. The total is output to the determination processing unit 28. The ratio calculation unit 27 calculates the ratio of pixels with a pixel value of 0 and outputs the result to the determination processing unit 28.

  The determination processing unit 28 performs determination processing based on the total number input from the number calculation unit 26 and the ratio input from the ratio calculation unit 27.

  Here, when the inside of the block being processed is located inside the copy prohibition code of all bits 0, a diagonal line pattern corresponding to a predetermined number of bits 0 or more is detected in the block, and bit 1 Since the hatched pattern corresponding to is hardly detected, the ratio of the hatched pattern corresponding to bit 0 should be high and almost close to 1.0.

  If the block currently being processed is located inside the copy prohibition code of all bits 1, a hatched pattern corresponding to a predetermined number of bits 1 or more is detected in the block, and bit 0 is set. Since the corresponding diagonal pattern is hardly detected, the ratio of the diagonal pattern corresponding to bit 0 should be low and almost close to 0.0.

  If the block currently being processed includes at least a part of the condition code, a diagonal line pattern corresponding to a plurality of bits 0 and a diagonal line pattern corresponding to a plurality of bits 1 are detected in the block. The ratio of the hatched pattern corresponding to 1 should be much lower than 1.0 and much higher than 0.

  Further, if the input image data is an image in which copy prohibition information is embedded, a copy prohibition code having all bits 0 in the block and a copy prohibition code having all bits 1 in the block are included in the image. There should be more than one embedded.

The following determination process is performed using the above characteristics.
If the total number> the first threshold value and the ratio> the second threshold value, the block is determined to be the copy prohibition code 0.
If the total number> the first threshold value and (1-ratio)> the second threshold value, the block is determined to be the copy prohibition code 1.
In cases other than the above, it is determined that the block is not a copy prohibition code. Also, the first threshold value is set by adding a margin to the number of theoretical patterns included in the block from the block size and pattern size. The second threshold value is set to a value close to 1.0.

  The determination processing unit 28 separately counts the number of blocks determined to be the copy prohibition code 0 and the number of blocks determined to be the copy prohibition code 1. When the number of blocks determined as copy prohibition code 0 is equal to or greater than threshold value 3 and the ratio determined as copy prohibition code 0 is a value close to 1.0, the image is determined to be a copy prohibition document; The determination result is output to the control unit 8.

Next, details of the copy permission condition information detection unit 12 will be described with reference to FIG.
The image data output from the scanner unit 2 is input to the gray scale conversion unit 31, converted from full color to gray scale, and then binarized by the binarization processing unit 32.

  The binarized image data is input to the noise removal processing unit 33, and noise removal processing is performed. The image data from which the noise has been removed is input to the pattern detection processing unit 34, where two types of oblique line pattern detection processing are performed, and the data of the processing result is stored in the buffer memory 35. In this image data, the pixel value at the position where the diagonal line pattern corresponding to bit 0 is detected is 0, the pixel value at the position where the diagonal line pattern corresponding to bit 1 is detected is 1, and other values are 2 The image data is 2 bits per pixel.

  The image data stored in the buffer memory 35 is input to the skew angle detection processing unit 36, and the skew angle is detected. Here, the skew angle of the input image data is obtained. As a specific method, Hough transform is performed on a pixel having only a pixel value of 0 or 1, and the peak of the projection distribution on the angle axis is obtained. The obtained skew angle is output to the code detector 37.

  Further, the image data stored in the buffer memory 35 is read out and input to the code detection unit 37, and the two-dimensional code is detected. Specifically, the image is scanned at the obtained skew angle to extract a pixel value of 0 or 1 (corresponding to 0 or 1 of the bit). The synchronization code is found from the extracted bit string. The synchronization code is defined as a code in which the outer periphery of a rectangular area having a predetermined vertical and horizontal size is entirely composed of bits 1. A bit array surrounded by the synchronization code is a two-dimensional code (condition code). This bit array is rearranged into a one-dimensional bit string and output to the error correction decoding unit 38.

  The error correction decoding unit 38 performs a predetermined error correction decoding process on the input bit string and decodes it as condition information. The decrypted copy permission condition information is output to the control unit 8.

  When the copy prohibition information and the copy permission condition information (hereinafter referred to as authentication information) are input from the embedded information detection unit 7 and the copy prohibition information is set in the document, the control unit 8 receives the user interface. The unit 9 displays an authentication information input request. In addition, the control unit 8 performs authentication by comparing the authentication information input from the user interface unit 9 with the authentication information read as copy permission condition information. Further, the control unit 8 takes in the image data from the image processing unit 3, generates a thumbnail image, and displays it on the display panel of the user interface unit 9.

  In the present embodiment having the above configuration, when a plurality of document images are read, a display that makes the correspondence between each page of the document and the authentication information set for each page clear is displayed on the user interface unit 9. Display on the display panel.

  Therefore, the control unit 8 generates a thumbnail image for each page, and displays the generated thumbnail image and a password input request for this page side by side on the display panel of the user interface unit 9. FIG. 6 shows the reading order of documents, and FIG. 7 shows a display example on the display panel. In the display example shown in FIG. 7, the thumbnail images and the password input request for the corresponding page are displayed in the order of the originals read by the scanner unit 2. Therefore, each page can be easily recognized by the thumbnail image, and the password set for each page can be easily input.

  If a password is set for only some pages of the document, the password input field of the page for which no password is set is in an inactive state so that input is not possible as shown in FIG. It can also be left.

  Further, since a page in which a user has entered a password and succeeded in authentication indicates that the authentication has been successful, the display form may be changed from a thumbnail of another page that has not been successfully authenticated. For example, when the password authentication is successful, the displayed thumbnail image is deleted (see FIG. 9A), the thumbnail image is displayed in a small size (see FIG. 9B), or “already” is displayed on the thumbnail image. The mark is displayed. When thumbnail images of a plurality of pages and a password input field are displayed on one screen, the user's convenience can be improved by displaying the page for which authentication has been completed normally in an easy-to-understand manner.

  Further, when the print setting is set to print a plurality of pages of the document on one page, the control unit 8 displays the thumbnail images and password input fields of the document pages to be printed on the same page as shown in FIG. Are displayed on the display panel. In FIG. 10, thumbnail images of the first and second pages to be printed on the same page and a password input field are displayed (see FIG. 10A), and the password of the page displayed on one screen is input. When the authentication is completed, the third and fourth pages of the document to be printed on the next page are displayed (see FIG. 10B).

The processing procedure of this embodiment will be described with reference to the flowchart shown in FIG.
The user sets a document bundle of original paper on the document setting unit of the scanner unit 2 and presses a start button on the user interface unit 9. When the start button is pressed (step S1 / YES), the control unit 8 starts reading a document. The document read by the scanner unit 2 is subjected to image processing by the image processing unit 3 and output to the control unit 8. The control unit 8 generates a thumbnail image of the input image (step S2).

  Next, the control unit 8 analyzes the code information detected by the embedded information detection unit 7 (step S3). When detecting the copy prohibition information as the code information (step S4 / YES), the control unit 8 determines whether or not a password is included as the code information (step S6). If the password can be detected (step S6 / YES), a thumbnail image and a password input request are displayed on the display panel as shown in FIG. 2 (step S2). If copy prohibition information cannot be detected (step S4 / NO), copying of the page is permitted (step S5). If the copy prohibition information is set (step S4 / YES), but the password is not set (step S6 / NO), copy of the page is prohibited (step S7).

  Thereafter, when a password from the user is input through the user interface unit 9 (step S9 / YES), the input password is compared with a password detected as code information from the document (step S10). If these passwords match (step S11 / YES), the control unit 8 permits copying of the page (step S13). When copying is permitted by the control unit 8, the image data processed by the image processing unit 3 is temporarily stored in the image storage unit 5, and then the image is output to the output unit 6 to form an image. If the input password does not match the password detected as code information from the document (step S11 / NO), the control unit 8 prohibits copying (step S12).

  The above-described processing is performed for all document pages read by the scanner unit 2 (step S14). When it is determined whether or not copying is permitted for all document pages (step S14 / YES), this process ends.

In this embodiment, the thumbnail images and the password input field are not displayed in the order of input of the scanner unit 2, but are displayed in order from image data that takes time for output processing. For example, as shown in FIG. 12, when documents of different sizes are mixed, thumbnail images of a large document and a password input field are displayed first, so that processing of large image data can be performed with a small image. It can be done ahead of the data. In FIG. 12, the first and third pages of the original are A4 size originals, and the second and fourth pages are A3 size originals. Therefore, as shown in FIG. The third thumbnail image and the password input request are displayed. When the authentication of these pages is completed, the second and fourth thumbnail images and the password input request are displayed.
By processing image data that takes time to process first, and processing image data that can be processed in a relatively short time later, the user can feel that the processing time has been shortened. Conversely, thumbnail images and password input fields may be displayed starting from the smallest size.

Further, when performing OCR processing, compression processing, or the like on the read image data, the order of documents displayed on the display panel may be changed in consideration of the time taken for OCR processing or compression processing.
For example, as shown in FIG. 14, when an OCR processing unit 50 that performs OCR processing is provided after the image processing unit 3, the image processing unit 3 performs T / I separation processing that separates text and images. The control unit 8 displays thumbnail images and password input requests in the order of increasing text data amount (see FIG. 15) or in ascending order according to the result of the T / I separation process.

  Also, as shown in FIG. 16, when a compression processing unit 51 for compressing an image is provided at the subsequent stage of the image processing unit 3, the standard deviation of a * and b * in the Lab color system is large in order from the largest. It is recommended to display a thumbnail image and a password input field. In the compression processing of the compression processing unit 51, the wider the color distribution width is, the more layers are required and the processing takes time. Therefore, it is possible to display the thumbnail image and the password input request from the troublesome processing to the user. Can give a feeling that the processing time has been shortened.

  The embodiment described above is a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.

It is a block diagram which shows the structure of an image processing apparatus. It is a figure which shows a background tint block image. It is a block diagram which shows the structure of a copy prohibition information detection part. It is a figure which shows an example of the image used for template matching. It is a block diagram which shows the structure of a copy permission condition information detection part. It is a figure which shows the image read by the scanner part. It is a display example of a display panel, and is a diagram showing an example in which thumbnail images and password input requests are displayed for each page. It is a display example of a display panel, and is a diagram in which a password input field of a page where no password is set is displayed in an inactive state. 4A and 4B are display examples of a display panel, in which FIG. 1A shows a page for which authentication has been completed by deleting a thumbnail image, and FIG. 2B shows a thumbnail image that has been reduced. FIG. 11 is a display example of the display panel, and is a diagram illustrating a display when a setting for printing a plurality of pages of a document on one page is made. It is a flowchart which shows the process sequence of an image processing apparatus. It is a figure which shows the image read by the scanner part, and is a figure which shows the case where the image from which original size differs is input. It is a display example of a display panel, and is a diagram illustrating a display example when images having different document sizes are input. It is a figure which shows the structure of the image processing apparatus provided with the OCR process part. It is a display example of a display panel, and is a diagram showing a display example in which the display order is changed according to the number of texts. It is a figure which shows the structure of the image processing apparatus provided with the compression process part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image processing apparatus 2 Scanner part 3 Image processing part 4 Accumulation / reading process part 5 Image storage part 6 Output part 7 Embedded information detection part 8 Control part 9 User interface part

Claims (8)

Input means for inputting image data;
Detection means for detecting user restriction information included in the input image data;
Thumbnail image generation means for generating a thumbnail image of the input image data;
When the user restriction information in the page that generated the thumbnail image is set to Yes and the thumbnail image, and a display control means for displaying on the display unit side by side and input request of the user restriction information,
The display control means displays a plurality of pages of thumbnail images and the user restriction information input request in the order of input by the input means .   The display control means is configured to display an input request for the user restriction information in a state where the user restriction information cannot be input when user restriction information is not set on the page where the thumbnail image is generated. Item 6. The image processing apparatus according to Item 1. Authentication means for comparing the match between the user restriction information input in accordance with the user restriction information input request and the user restriction information detected from the image data;
The display control means reduces the thumbnail image of the page that has been successfully authenticated by the authentication means, changes the display color of the thumbnail image of the page that has been successfully authenticated, and erases the thumbnail image of the page that has been successfully authenticated 3. The image processing apparatus according to claim 1, wherein any one of the displays indicating that the authentication is completed is displayed on the thumbnail image of the page that has been successfully authenticated.   When the display control means is set to print a plurality of pages of image data input by the input means on one page, the display means collectively sends the thumbnail images of the plurality of pages and an input request for user restriction information to the display means. The image processing apparatus according to claim 1, wherein the image processing apparatus is displayed.   2. The display control unit according to claim 1, wherein the display control unit changes the display order of the thumbnail images of a plurality of pages and the input request for the user restriction information according to the size of the image data input by the input unit. Image processing apparatus. Separating means for separating the image data into image data and text data;
The display control means changes a display order of a plurality of thumbnail images and an input request for the user restriction information according to a data amount of text data included in the image data. The image processing apparatus described.   The image processing apparatus according to claim 1, wherein the display control unit changes a display order of a plurality of thumbnail images and an input request for the user restriction information according to a hue distribution of image data. Inputting image data;
Detecting user restriction information included in the input image data;
Generating a thumbnail image of the input image data;
When the user restriction information in the page that generated the thumbnail image is set to Yes and the thumbnail image, and a step of displaying on the display unit side by side and input request of the user restriction information, the step of the display A display control method for displaying thumbnail images of a plurality of pages and an input request for the user restriction information in the input order of the input step .

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