JP4803243B2 - Image processing apparatus and image processing program - Google Patents

Description

  The present invention relates to an image processing apparatus and an image processing program.

  In the image processing technology, there is a technology for reducing the memory required for image comparison.

In Patent Document 1, when an image output on paper is read by a scanner, and the read image is compared with the original image to determine whether the output image is appropriate, the image comparison is conventionally performed on a page-by-page basis. An image forming apparatus that realizes reduction in memory and improvement in processing speed has been proposed by comparing the above into several areas.
JP 2006-06076 A

  It is an object of the present invention to propose an image processing apparatus and an image processing program for reducing the memory capacity of a line memory by storing a line memory necessary for pattern matching at a low resolution at a portion not related to pattern detection. .

In order to achieve the above object, the image processing apparatus according to claim 1 receives the image data of the determination target image and sequentially shifts and stores the image data of the determination target image in units of lines. A first line memory having a memory and storing image data of a first region including a target pixel of the determination target image at a first resolution; and a final plurality of line memories of the first plurality of line memories. A second plurality of line memories for inputting logical sums of stored image data and sequentially storing them in line units, and corresponding to the image data stored in the first line memory of the judgment image A second line memory for storing an image of a second region excluding the image to be processed at a second resolution lower than the first resolution, and the pixel of interest from the image data stored in the first line memory. The A first determination area generating means for generating a first determination area for determining whether or not formed, stored in the first image data and the stored in the line memory of the second line memory Second determination area generating means for generating a second determination area for determining whether or not the target pixel constitutes a tint block based on peripheral pixels of the target pixel from image data; and the first determination area First determination means for comparing the image data of the first region generated by the generation means with reference image data stored in advance to determine whether the pixel of interest constitutes a tint block; and the second It is determined whether or not the target pixel constitutes a tint block with reference to image data of a pixel located at a predetermined distance from the target pixel in the image data of the second region generated by the determination region generation unit. Second determination means It said first judging means and the second judging means determining means for determining whether the pixel of interest constitutes a background pattern by whether the determination result were both determined to the pixel of interest constitutes a background pattern It is comprised so that it may comprise.

According to a second aspect of the present invention, in the first aspect of the invention, the second determination unit includes the pixel of interest in the image data of the second region generated by the second determination region generation unit. It is configured to determine whether or not the pixel of interest constitutes a tint block by referring to image data of a pixel whose relative position from is at a predetermined angle .

According to a third aspect of the present invention, in the first or second aspect of the present invention, the first determination area generation means generates the first determination from the image data of each pixel stored in the first plurality of line memories. A determination area is generated, and the second determination area generation means generates the second determination area from image data of each pixel stored in the first plurality of line memories and the second plurality of line memories. Configured to generate .

According to a fourth aspect of the present invention, there is provided an image processing program in which a computer inputs first image data of a determination target image and sequentially shifts and stores the image data of the determination target image in units of lines. Means for storing image data of a first region including a target pixel of the determination target image at a first resolution in a first line memory having a first resolution, and storing the image data in a final plurality of line memories of the first plurality of line memories Stored in the first line memory of the determination image in a second line memory having a second plurality of line memories for inputting the logical sum of the image data and sequentially shifting and storing them in line units Means for storing an image of a second area excluding an image corresponding to the image data at a second resolution lower than the first resolution, whether the image data is stored in the first line memory; First determination area generation means for generating a first determination area for determining whether or not the pixel of interest constitutes a tint block, image data stored in the first line memory, and the second line Second determination area generating means for generating a second determination area for determining whether or not the target pixel constitutes a tint block based on the peripheral pixels of the target pixel from the image data stored in the memory; First determination means for determining whether or not the target pixel constitutes a tint block by comparing the image data of the first area generated by one determination area generation means with reference image data stored in advance; Image data of pixels in the second region image data generated by the second determination region generation means that are at a predetermined distance from the target pixel and whose relative position from the target pixel is at a predetermined angle. The The second determination means for determining whether or not the pixel of interest constitutes a tint block, and whether the first determination unit and the second determination unit all determine that the pixel of interest constitutes a tint block the target pixel by whether the determination result of Ru to function as determination means for determining whether or not constituting the background pattern.

  According to the first aspect of the present invention, there is an effect that it is possible to determine whether or not to form a copy-forgery-inhibited pattern with a line memory having a smaller storage capacity than in the case of not constituting the present invention.

  Further, according to the second aspect of the present invention, it is possible to determine whether or not to form a copy-forgery-inhibited pattern with a line memory having a smaller storage capacity than in the case where the present invention is not configured.

  Further, according to the invention of claim 3, there is an effect that it is possible to determine whether or not to form a copy-forgery-inhibited pattern with a line memory having a smaller storage capacity than in the case where the present invention is not configured.

  According to the invention of claim 4, it is possible to determine whether or not the copy-forgery-inhibited pattern can be configured with a line memory having a smaller storage capacity than in the case where the present invention is not configured.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  First, an image processing apparatus 1 according to the present invention will be described with reference to FIG.

  The image processing apparatus 1 is an apparatus that reads a background pattern printed on a document and performs various processes.

  As shown in FIG. 1, the image processing apparatus 1 includes a scanner unit 2, a display / operation unit 3, a page memory 4, a ROM (Read Only Memory) 5, a RAM (Random Access Memory) 6, a control unit 7, and a print engine 8. And an image processing ASIC (Application Specific Integrated Circuit) 9.

  The scanner unit 2 optically reads a document that is paper, and acquires image data of the document.

  The display / operation unit 3 is composed of a liquid crystal touch panel and manages the function of the user interface.

  The page memory 4 temporarily stores document image data acquired by the scanner unit 2.

  The ROM 5 is a non-rewritable nonvolatile memory that stores firmware and the like for operating the image processing apparatus 1 and also stores an image processing program for operating the image processing ASIC 9.

  The control unit 7 is composed of a central processing unit, and comprehensively controls the image processing apparatus 1 to perform print control according to the contents embedded in the background pattern printed on the document set on the scanner unit 2. .

  A copy-forgery-inhibited pattern is printed as a digital watermark technique on a document set in the scanner unit 2, and document attribute information such as an ID of a printer who printed the document and a printing date / time is embedded in the copy-forgery-inhibited pattern.

  The control unit 7 reads attribute information such as the printer ID and printing date embedded in the background pattern, and performs processing such as copy control of the document on which the background pattern is printed and information source tracking.

  The image processing ASIC 9 includes a pattern detection module 10 that detects a background pattern from a document, and creates a background pattern image based on the detected background pattern.

  The pattern detection module 10 that detects a background pattern in image data includes a line memory A11, a line memory B12, a window generation unit 13, and a background pattern detection unit 14.

  The line memory A11 is a first-in first-out (FIFO) memory, and is a line memory having 16 lines.

  The line memory A11 is a line memory that stores image data input to the line memory A11 so that it can be expressed with a resolution of 600 dpi.

  The line memory B12 is a FIFO memory, and is a line memory that stores image data input to the line memory B12 with a resolution of 300 dpi. Therefore, the line memory B12 requires less storage capacity than the line memory A11.

  Further, the line memory B12 includes an OR operator 15.

  The OR operator 15 logically processes the two lines of image data in the line memory A11 so that the image data sent from the line memory A11 expressed at a resolution of 600 dpi is expressed by the line memory B12 expressed at a resolution of 300 dpi. One line of image data is obtained by summation.

  The window generation unit 13 includes a plurality of flip-flop circuits, and generates, as a window, image data obtained by cutting out part of the image data on the document based on the image data stored in the line memory A11 and the line memory B12.

  Based on the image data generated by the window generation unit 13, the background pattern detection unit 14 detects whether image data of a pixel at a predetermined position in the window is formed as a background pattern.

  In the image processing apparatus 1 configured as described above, when a document on which a copy-forgery-inhibited pattern is superimposed and printed on a document image is set on the scanner unit 1 and read, image data of the read document is sent to the image processing ASIC 9. The ASIC 9 detects the background pattern.

  The process of detecting the background pattern from the image data of the document is performed by the pattern matching process by the pattern detection module 10 included in the image processing ASIC 9.

  Whether or not the pixel is a background pattern is determined by processing such as whether or not there is an arrangement pattern peculiar to the background pattern stored in advance around one pixel detected on the image data of the document.

  Next, a process in which a document is scanned in the image processing apparatus 1 and a background pattern on the document is read will be described with reference to FIG.

  FIG. 2 is a schematic diagram briefly explaining the processing performed in the image processing apparatus 1.

  First, a document is placed on the scanner unit 2, and image data of the document is read by the scanner unit 2.

  The acquired image data of the document is sent to the image processing ASIC 9, and the pattern detection module 10 detects the background pattern printed on the document in a superimposed manner.

  As shown in FIG. 3, the image data sent to the pattern detection module 10 is sequentially input to the line memory A11 every 38 pixels for one line of the line memory A11.

  Image data output from the line memory A11, which is a FIFO memory, is input to a line memory B12, which is a FIFO memory.

  Then, based on the image data stored in the line memory A11 and the line memory B12, a window is generated as image data in which a part of the document is cut out by the window generation unit 13, and the tint block detection unit 14 generates a predetermined window in the window. The tint block determination of the pixels is performed.

  Then, after the background pattern determination is performed for all the pixels of the image data of the document acquired by the scanner unit 2, a background pattern image in which all detected background patterns are combined is generated by the image processing ASIC 9, and the control unit 7 Sent to.

  The control unit 7 reads information such as a printer ID and printing date embedded in the copy-forgery-inhibited pattern image from the copy-forgery-inhibited pattern image sent from the image processing ASIC 9, and the document set on the scanner unit 2 based on the read information. Processes such as copy control. For example, based on the printer ID embedded in the copy-forgery-inhibited pattern image of the original, the image processing apparatus 1 does not permit copying of the printed material of the printer.

  Next, the configuration of the pattern detection module 10 will be described with reference to FIG.

  FIG. 4 is a schematic diagram showing the configuration of the pattern detection module 10.

  As shown in FIG. 4, the pattern detection module 10 includes a line memory A <b> 11, a line memory B <b> 12, a window generation unit 13, and a tint block detection unit 14.

  When image data for one line of 38 pixels of a document is newly input to the lowermost line of the line memory A11, the process of sequentially sending the image data stored up to that point to the next upper line (next line) This is done in the memory A11.

  Separately, the stored image data is sent to the line memory B12 from the top two lines of the line memory A11.

  In the line memory B12, the image data sent from the top line of the line memory A11 and the line below it is passed through the OR operator 15 and one line of image data in the line memory B12 of 300 dpi expression. And then stored in the line.

  In the line memory B12, each time new image data is stored in a line, the processing specific to the FIFO memory is performed in which the image data stored in the line is sequentially moved to the next (next) line.

  The image data stored in the line memory A11 and the line memory B12 is sent to the window generation unit 13 for window generation before being sequentially moved to the upper line.

  Next, a background pattern detection window generated by the window generation unit 13 will be described with reference to FIG.

  FIG. 5 is a schematic diagram showing a window generated by the window generation unit 13.

  The window generated by the window generation unit 13 includes image data (reference number 502) sent from the line memory A11 and image data (reference number 503) sent from the line memory B12.

  A window generated by the image data sent from the line memory A11 is expressed by a resolution of 600 dpi (reference number 502), whereas a window generated by the image data sent from the line memory B12 is expressed by a resolution of 300 dpi (reference numeral 502). Reference number 503).

  Then, attention is paid to the image data (reference number 501 in the example shown in FIG. 5) input to a predetermined position (flip-flop circuit at a predetermined position) in the window generated by the window generation unit 13, and the predetermined position It is determined whether or not the pixel is a background pattern (background pattern determination of the target pixel in the claims).

  Judgment as to whether the pattern is a tint block is performed by pattern matching or the like.

  First, pattern matching with a pre-stored background pattern is performed in a window (reference number 502) generated by the window generator 13 from image data sent from the line memory A11.

  The pattern matching with the pre-stored background pattern performed in the window (reference number 502) generated by the window generation unit 13 from the image data sent from the line memory A11 is the periphery of the target pixel for which it is determined whether or not it is a background pattern Pattern matching based on matching between the image data (reference number 504) and the copy-forgery-inhibited pattern image data stored in advance.

  Then, in the window (reference number 505) generated by the window generation unit 13 from the image data sent from the line memory A11 and the line memory B12, a distance 12 pixels away from the target pixel (see FIG. 6A). It is determined whether or not the image data that is the background pattern is arranged at 90 degrees (see FIG. 6B).

  If image data that is a copy-forgery-inhibited pattern exists at a distance of 12 pixels from the target pixel (reference number 501), it is determined whether or not the relative position (relative angle) from the target pixel is 90 degrees. The

  Generated by the window generator 13 from the pattern matching result in the window (reference number 502) generated from the image data sent from the line memory A11 and the image data sent from the line memory A11 and the line memory B12. The judgment results in the window (reference number 505) are integrated, and it is judged whether or not the target pixel is composed of a background pattern.

  The determination of whether or not the pixel of interest is a background pattern from the image data generated by the window generation unit 13 is all performed by the background pattern detection unit 14.

  Therefore, if the image data in the window has a resolution of 600 dpi that is closely related to pattern detection (reference number 502), the other portion that is not related to pattern detection (reference number 503) is stored at a resolution of 300 dpi. May be.

  The ratio of the image data sent from the line memory B12 to the window generated by the window generation unit 13 and the position thereof may be arbitrarily changed according to the shape and arrangement of the background pattern to be pattern-matched. In short, the line memory that sends the image data that is not related to the pattern matching of the tint block to the window generation unit 13 may be a memory that stores the image data at a lower resolution than the others.

  Next, the image data for one line of the original is input to the line memory A11 one after another, and the window generated by the window generation unit 13 every time the image data for one line is input is described with reference to FIG. Give an explanation.

  FIG. 7 is a schematic diagram showing a process in which image data for one line of a document is successively input to the line memory A11 and windows are generated one after another by the window generation unit 13.

  FIG. 7A is a schematic diagram showing a state in which a window for detecting a tint block is generated based on image data stored in the line memory A11 and the line memory B12. FIG. FIG. 7C is a schematic diagram showing a window created after one line of image data is input to the line memory A11 from the state shown in FIG. 7C. FIG. 7C shows the line memory from the state shown in FIG. It is a schematic diagram which shows the window produced after the image data for 1 line is further input into A11.

  As shown in FIG. 7A, from the image data stored in the line memory A11, image data with a resolution of 600 dpi is sent to the window generation unit 13 to create a window, and the image data stored in the line memory B12 The image data with a resolution of 300 dpi is sent to the window generator 13 to generate a window.

  When a window as shown in FIG. 7A is generated, whether or not the image data arranged at a predetermined position in the window is a background pattern is determined by pattern matching by the background pattern detection unit 14. In the example shown in FIG. 7A, it is determined that the pattern is not a background pattern.

  Thereafter, when image data for one line of the original is input to the line memory A11, as shown in FIG. 7B, the image data is one line higher (next) for each line in the line memory A11. Are moved sequentially.

  When the sequential movement of the image data stored in the line memory A11 and the line memory B12 is completed, the image data stored in the line memory A11 and the line memory B12 after the movement is sent to the window generation unit 13, and FIG. A window for detecting a tint block is generated as shown in FIG.

  Then, as shown in FIG. 7B, the background pattern detection unit 14 determines whether the image data arranged at a predetermined position of the window newly generated by the window generation unit 13 is a background pattern. In the example shown in FIG. 7B, it is determined to be a background pattern.

  Thereafter, the image data for one line of the original is input to the line memory A11, and as shown in FIG. 7C, the image data is moved up one line for each line (next) in the line memory A11. It is moved sequentially.

  When the sequential movement of the image data stored in the line memory A11 and the line memory B12 is completed, the image data stored in the line memory A11 and the line memory B12 after the movement is sent again to the window generation unit 13, and FIG. As shown in c), a window for ground detection is generated.

  Then, as illustrated in FIG. 7C, the background pattern detection unit 14 determines whether the image data arranged at a predetermined position of the window newly generated by the window generation unit 13 is a background pattern. In the example shown in FIG. 7C, it is determined to be a background pattern.

  In this way, the background pattern detection is performed by the window generated by the image data stored in the line memory A11 and the line memory B12.

  The tint block detection process performed by the tint block detection unit 14 is not limited to the above-described pattern matching process, and image data at a predetermined position (reference number 501) in the window is a tint block pattern by other processes. A determination of whether or not there may be made.

  The image processing apparatus 1 can process not only the image data of the document read by the scanner unit 2 but also the image data of the document received via the communication line. At that time, the image data of the document received from the communication IF unit (not shown) is sent to the image processing ASIC 9 for processing.

  The present invention can be used in an image processing apparatus and an image processing program.

  The image processing program of the present invention can be provided not only by communication means but also by being recorded on a recording medium such as a CD-ROM.

1 is a configuration diagram of an image processing apparatus 1. FIG. FIG. 3 is a schematic diagram briefly explaining processing performed in the image processing apparatus 1. FIG. 3 is a schematic diagram in which image data of a document is input to a line memory A11 in units of lines. 4 is a schematic diagram showing a configuration included in the pattern detection module 10. FIG. The schematic diagram which shows the window which the window generation part 13 produces | generates. The schematic diagram which shows an example of background pattern arrangement | positioning. The schematic diagram which shows a mode that a window is produced | generated sequentially.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image processing apparatus 7 Control part 9 Image processing ASIC
10 Pattern detection module 11 Line memory A
12 line memory B
13 Window generation unit 14 Background pattern detection unit 15 OR operator

Claims (4)

A first plurality of line memories for inputting the image data of the determination target image and sequentially storing the image data of the determination target image in units of lines, the first line memory including a target pixel of the determination target image; A first line memory for storing image data of a region at a first resolution;
A second plurality of line memories for inputting a logical sum of the image data stored in the last plurality of line memories of the first plurality of line memories and sequentially shifting and storing them in units of lines ; A second line memory for storing an image of a second region excluding an image corresponding to the image data stored in the first line memory at a second resolution lower than the first resolution;
First determination area generation means for generating a first determination area for determining whether or not the pixel of interest constitutes a tint block from image data stored in the first line memory;
For determining whether or not the pixel of interest constitutes a tint block based on the surrounding pixels of the pixel of interest from the image data stored in the first line memory and the image data stored in the second line memory Second determination area generation means for generating a second determination area;
First determination means for comparing the image data of the first area generated by the first determination area generation means with reference image data stored in advance to determine whether or not the target pixel constitutes a background pattern. When,
Whether the target pixel constitutes a background pattern with reference to image data of a pixel at a predetermined distance from the target pixel in the image data of the second region generated by the second determination region generation unit Second determination means for determining whether or not
Determining means for determining whether or not the target pixel constitutes a tint block based on a determination result of whether or not the first judging unit and the second judging unit determine that the target pixel constitutes a tint block; An image processing apparatus comprising: The second determination means includes
With reference to the image data of the pixel whose relative position from the target pixel of the second region of the image data generated by the second determination region generation unit is at a predetermined angle, the target pixel is The image processing apparatus according to claim 1, wherein it is determined whether or not to form a tint block . The first determination area generation means includes:
Generating the first determination region from the image data of each pixel stored in the first plurality of line memories;
The second determination area generation means includes:
The second determination area is generated from image data of each pixel stored in the first plurality of line memories and the second plurality of line memories.
The image processing apparatus according to claim 1 . Computer
The target pixel of the determination target image is stored in a first line memory having a first plurality of line memories that input image data of the determination target image and sequentially store the image data of the determination target image in units of lines. Means for storing image data of a first region including a first resolution;
A second line memory having a second plurality of line memories for inputting a logical sum of the image data stored in the last plurality of line memories of the first plurality of line memories and sequentially shifting and storing them in line units. Means for storing an image of a second area excluding an image corresponding to image data stored in the first line memory of the determination image at a second resolution lower than the first resolution;
First determination area generation means for generating a first determination area for determining whether or not the pixel of interest constitutes a tint block from the image data stored in the first line memory;
For determining whether or not the pixel of interest constitutes a tint block based on the surrounding pixels of the pixel of interest from the image data stored in the first line memory and the image data stored in the second line memory Second determination area generation means for generating a second determination area;
First determination means for comparing the image data of the first area generated by the first determination area generation means with reference image data stored in advance to determine whether or not the target pixel constitutes a background pattern. ,
An image of a pixel in the second area image data generated by the second determination area generation unit that is at a predetermined distance from the target pixel and whose relative position from the target pixel is at a predetermined angle. Second determination means for determining whether or not the target pixel constitutes a tint block by referring to data;
Determination means for determining whether or not the target pixel constitutes a background pattern based on a determination result of whether or not the first determination means and the second determination means both determine that the target pixel constitutes a background pattern.
Image processing program to function as

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