JP2013041496A - Color two-dimensional barcode generation apparatus, color two-dimensional barcode reading device, method for generating color two-dimensional barcode, method for reading color two-dimensional barcode, and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further surely detect a plurality of two-dimensional barcodes from a color two-dimensional barcode compared with the conventional one even when repeating the generation copy.SOLUTION: The color two-dimensional barcode generation apparatus acquires a first two-dimensional barcode 41 and a second two-dimensional barcode 42 that have chromatic cells with mutually different colors, as a plurality of two-dimensional barcodes; and generates a color two-dimensional barcode 43 by superimposing the first two-dimensional barcode 41 and the second two-dimensional barcode 42 with each other, with cells on a same position displaced by a fixed distance. Then, the color two-dimensional barcode generation apparatus outputs the color two-dimensional barcode 43.

Description

  The present invention relates to a color two-dimensional barcode technology.

  2. Description of the Related Art Conventionally, a technique has been proposed in which two two-dimensional barcodes having different colors are combined to form a single color two-dimensional barcode. According to this technique, character strings represented by two two-dimensional barcodes can be collectively represented as one color two-dimensional barcode. When the reading device reads the color two-dimensional barcode, the reader determines the original two-dimensional barcode based on the color of each cell, and analyzes the character string represented by the two-dimensional barcode (Patent Document 1).

  Further, a monochrome (single color) two-dimensional barcode can represent only one bit per cell. However, a color (multiple color) two-dimensional barcode can represent multiple bits per cell. In view of this, a method has been proposed in which two-dimensional barcodes are colorized to represent more data than monochrome two-dimensional barcodes (Patent Document 2).

  In addition, it has been proposed that the shape of the two-dimensional barcode cell is different from the conventional one (Patent Document 3). A color one-dimensional barcode has also been proposed (Patent Document 4).

JP 2009-123179 A Japanese Patent Laid-Open No. 9-212574 JP 2006-4378 A JP-A-8-96097

  By the way, if the printed matter of the color two-dimensional barcode is copied, the copied material is copied, and so on, that is, if the generation copy is repeated, the reproducibility of the cell color and gradation is lowered. For example, if you repeat the generation copy of a color two-dimensional barcode generated by superimposing a magenta two-dimensional barcode and a cyan two-dimensional barcode, cyan will approach the blue of the overlapping part of both colors, and will be distinguished? Disappear.

  Then, it becomes impossible to detect a plurality of two-dimensional barcodes having different colors from the color two-dimensional barcode.

  In view of such a problem, the present invention has an object to make it possible to more reliably detect a plurality of two-dimensional barcodes from a color two-dimensional barcode even when generation copy is repeated. To do.

  A color two-dimensional barcode generation apparatus according to an aspect of the present invention, a plurality of two-dimensional barcodes, a plurality of two-dimensional barcode acquisition means for acquiring a plurality of two-dimensional barcodes having different colors of colored cells; A color two-dimensional barcode generating means for generating a color two-dimensional barcode by superimposing the plurality of two-dimensional barcodes by shifting cells at the same position by a certain distance, and the color two-dimensional barcode Color two-dimensional bar code output means for outputting a code.

  Preferably, the color two-dimensional barcode generation unit generates the color two-dimensional barcode by overlapping the plurality of two-dimensional barcodes without shifting the cells constituting the position detection pattern or the alignment pattern. To do. Further preferably, the color two-dimensional barcode generation means generates the color two-dimensional barcode using black as the color of the cells constituting the position detection pattern or alignment pattern.

  A color two-dimensional barcode reader according to an aspect of the present invention is generated by superimposing a plurality of two-dimensional barcodes having different colors of colored cells by shifting cells at the same position by a certain distance. A color two-dimensional barcode acquisition means for acquiring a color two-dimensional barcode; and a plurality of cells in the color two-dimensional barcode that are shifted by a certain distance and overlap each other. A shape detecting means for detecting a shape of a colored pixel group composed of pixels; and when the shape detected from the area is the same as a shape of one cell, the color of the colored pixel group in the area is detected. If it is determined that the color of the colored pixel group is the detected color and the shape is the same as the shape obtained by shifting and overlapping a plurality of cells, For each cell portion that is a portion corresponding to one cell, the color of another cell located right above, right under, right left, or right is detected, and the portion of the cell portion that does not overlap with another cell portion Color discriminating means for discriminating that the color of the cell is the detected color and that the color of the portion overlapping with the other cell portion is a composite color of the detected color for each of the cell portion and the other cell portion And two-dimensional barcode specifying means for specifying each of the plurality of two-dimensional barcodes based on the color of each pixel of the color two-dimensional barcode determined by the color determination means.

  According to the present invention, even when generation copy is repeated, a plurality of two-dimensional barcodes can be detected from a color two-dimensional barcode more reliably than before.

1 is a diagram illustrating an example of an overall configuration of a network system including an image forming apparatus. 2 is a diagram illustrating an example of a hardware configuration of an image forming apparatus. FIG. FIG. 2 is a diagram illustrating an example of the configuration of a scan unit and a printing unit of an image forming apparatus. It is a figure which shows the example of a structure of an image processing circuit. It is a figure which shows the example of a structure of a color two-dimensional barcode provision part. It is a figure which shows the example of superposition of two cells. It is a figure which shows the example of a production | generation of a color two-dimensional barcode. It is a figure which shows the example of a structure of a color two-dimensional barcode analysis part. It is a figure which shows the example of a detection of a 1st two-dimensional barcode and a 2nd two-dimensional barcode. It is a figure which shows the example of the discoloration of a colored cell. It is a figure which shows the example of the color two-dimensional barcode which repeated the generation copy. It is a figure which shows the example of arrangement | positioning of a survey area, a 1st part, a 2nd part, and a 3rd part. It is a figure which shows the example of the 1st form of the investigation object area thru | or a 3rd form. It is a figure which shows the example of a search of a colored cell. It is a figure which shows the modification of the production | generation method of a color two-dimensional barcode. It is a figure which shows the modification of the detection method of a 1st two-dimensional barcode and a 2nd two-dimensional barcode. It is a figure which shows the example of the flow of a process which produces | generates a color two-dimensional barcode. It is a flowchart explaining the example of the flow of a process which detects a 1st two-dimensional barcode and a 2nd two-dimensional barcode.

  FIG. 1 is a diagram illustrating an example of the overall configuration of a network system including an image forming apparatus 1. FIG. 2 is a diagram illustrating an example of a hardware configuration of the image forming apparatus 1. FIG. 3 is a diagram illustrating an example of the configuration of the scan unit 10e and the print unit 10f of the image forming apparatus 1.

  In FIG. 1, an image forming apparatus 1 is an apparatus generally called an MFP (Multi Function Peripherals) or a multifunction machine, and has functions such as copying, PC printing (network printing), fax, scanner, and document server. Device.

  The image forming apparatus 1 can communicate with a device such as the terminal device 2 via the communication line NW.

  2 and 3, the image forming apparatus 1 includes a CPU (Central Processing Unit) 10a, a RAM (Random Access Memory) 10b, a ROM (Read Only Memory) 10c, a mass storage device 10d, a scan unit 10e, In addition to the printing unit 10f, the network interface 10g, the operation panel 10h, the facsimile unit 10i, the image processing circuit 10j, and the automatic document feeder 10k, it is configured by a control circuit and the like.

  The CPU 10 a is a control unit that performs overall control of the image forming apparatus 1. Software such as an operating system and middleware for realizing the above-described functions is installed in the ROM 10c or the mass storage device 10d. Software modules constituting the software are loaded into the RAM 10b as necessary and executed by the CPU 10a. For example, the ROM 10c or the large-capacity storage device 10d stores image data for each main scanning line in synchronization with software for performing various data processing such as shading correction on the image data obtained by the scan unit 10e, or paper supply. Software that reads and drives the laser diode is installed. An HDD (Hard Disk Drive), an SSD (Solid State Drive), or the like is used as the mass storage device 10d.

  The network interface 10g communicates with a device such as the terminal device 2 via a communication line NW using a protocol such as TCP / IP (Transmission Control Protocol / Internet Protocol). For example, a network interface card (NIC) is used as the network interface 10g.

  The operation panel 10h includes a key input unit 10h1, a touch panel display 10h2, a sub power switch 10h3, and the like.

  The key input unit 10h1 is a so-called hardware key, and includes a numeric keypad, a start key, a stop key, a function key, and the like.

  The touch panel display 10h displays a screen for giving a message or an instruction to the user, a screen for the user to input processing commands and conditions, a screen showing the processing result of the CPU 10a, and the like. Moreover, the position which the user touched with the finger | toe is detected and the signal which shows a detection result is transmitted to CPU10a.

  The touch panel display 10h2 includes a screen for giving a message or an instruction to the user, a screen for inputting a processing type and processing conditions desired by the user, a screen showing a result of processing executed by the CPU 10a, etc. Is displayed. The user can input information and commands to the image forming apparatus 1 by operating the key input unit 10h1 or the touch panel display 10h2 while viewing these screens.

  The sub power switch 10h3 is a switch for the user to instruct the image forming apparatus 1 to shift to a power saving mode such as a sleep mode.

  The image processing circuit 10j performs processing for collecting two two-dimensional barcodes into one color two-dimensional barcode and processing for extracting two two-dimensional barcodes from the color two-dimensional barcode. Details of these processes will be sequentially described later. The image processing circuit 10j can be configured by an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA).

  The automatic document feeder 10k is an ADF (Auto Document Feeder), and conveys documents set on the document feed tray one by one to a predetermined position on the platen glass of the scan unit 10e, and the document by the scan unit 10e. Is read out to the document discharge tray.

  The automatic document feeder 10k includes a document set sensor 10k1. The document set sensor 10k1 detects that a document has been set by a known tact switch and notifies the CPU 10a.

  The scan unit 10e reads an image composed of a photograph, a character, a picture, a chart, and the like written on a document (paper) set on a platen glass and generates image data. In particular, in this embodiment, it is used for reading the above-described color two-dimensional barcode.

  Further, the scan unit 10e includes an apparatus lifting sensor 10e1. The apparatus lifting sensor 10e1 detects that the automatic document feeder 10k has been lifted by a known magnetic sensor and notifies the CPU 10a.

  The facsimile unit 10i is a device for exchanging image data with a fax terminal using a protocol such as G3 via a public telephone line.

  In addition to the image read by the scan unit 10e, the printing unit 10f prints an image indicated by image data received from the terminal device 2 or a fax terminal on a sheet. The color two-dimensional barcode generated by the image processing circuit 10j is printed on a sheet.

  The printing unit 10f includes an image forming unit 11, an automatic duplex unit 12, a paper feeding unit 13, a paper feeding cabinet 14, and the like.

  The image forming unit 11 is a tandem and electrophotographic color printing engine, and includes photosensitive drums 31a, 31b, 31c, and 31d, exposure scanning units 32a, 32b, 32c, and 32d, a transfer belt 33, and The front door sensor 34 is configured.

  The photosensitive drums 31a, 31b, 31c, and 31d are photosensitive drums corresponding to yellow, magenta, cyan, and black, respectively. Similarly, the exposure scanning units 32a, 32b, 32c, and 32d are exposure scanning units corresponding to yellow, magenta, cyan, and black, respectively.

  The exposure scanning units 32a, 32b, 32c, and 32d respectively expose the electrostatic latent images on the photoreceptors 31a, 31b, 31c, and 31d by performing exposure according to the image to be printed based on the signal from the CPU 10a. Create an image. Then, toner of each color adheres.

  On the transfer belt 33, toner images of respective colors formed on the photoreceptors 31a, 31b, 31c, and 31d are overlaid. As a result, a full-color toner image is formed on the transfer belt 33.

  The front door sensor 34 detects that the front door cover has been opened by a known tact switch, and notifies the CPU 10a.

  The paper supply unit 13 is a unit that is provided in the image forming apparatus 1 as a standard and supplies paper to the image forming unit 11. The paper feed unit 13 includes one or a plurality of paper feed cassettes 13a and pickup rollers 13b. Sheets are stored in the sheet cassette 13a. The pickup roller 13 b picks up the sheets one by one from the paper feed cassette 13 a and carries them out to the image forming unit 11.

  The paper feed cabinet 14 is a unit that supplies paper to the image forming unit 11 in the same manner as the paper feed unit 13, but is provided as an option in the image forming apparatus 1. The sheet fed from the sheet feeding cassette 14 a of the sheet feeding cabinet 14 by the pickup roller 14 b is supplied to the image forming unit 11 via the sheet feeding unit 13.

  Then, the toner image formed on the transfer belt 33 is transferred onto the paper carried out from the paper supply unit 13 or the paper supply cabinet 14.

  The automatic duplex unit 12 reverses the front and back sides of the sheet on which the image is printed on one side, temporarily switches back on the sheet passing path, and feeds the image to the image forming unit 11 again. Thereby, double-sided printing becomes possible.

  Returning to FIG. 1, the terminal device 2 is a client for receiving services such as printing by the image forming apparatus 1. A driver or the like for controlling the image forming apparatus 1 is installed in the terminal device 2. As the terminal device 2, a personal computer, a smartphone, a PDA (Personal Digital Assistant), or the like is used.

  FIG. 4 is a diagram illustrating an example of the configuration of the image processing circuit 10j. FIG. 5 is a diagram illustrating an example of the configuration of the color two-dimensional barcode providing unit 5. FIG. 6 is a diagram showing an example of superposition of two cells. FIG. 7 is a diagram illustrating an example of generation of the color two-dimensional barcode 43. FIG. 8 is a diagram illustrating an example of the configuration of the color two-dimensional barcode analysis unit 6. FIG. 9 is a diagram illustrating an example of detection of the first two-dimensional barcode 41 and the second two-dimensional barcode 42. FIG. 10 is a diagram illustrating an example of color change of a colored cell. FIG. 11 is a diagram showing an example of the color two-dimensional barcode 43 in which generation copy is repeated. FIG. 12 is a diagram illustrating an example of the arrangement of the survey target area BR, the first part BRa, the second part BRb, and the third part BRc. FIG. 13 is a diagram illustrating an example of the first to third forms of the survey target area BR. FIG. 14 is a diagram illustrating an example of searching for a colored cell.

  Next, the processing of the two-dimensional barcode by the image processing circuit 10j will be described with reference to FIG.

  The image processing circuit 10j includes a color two-dimensional barcode providing unit 5 and a color two-dimensional barcode analyzing unit 6, as shown in FIG.

  As shown in FIG. 5, the color two-dimensional barcode providing unit 5 includes a two-dimensional barcode generation unit 501, a color conversion unit 502, a cell overlap ratio determination unit 503, a color two-dimensional barcode generation unit 504, and a color two-dimensional The barcode printing unit 505 is configured. With these configurations, two two-dimensional barcodes are combined into one color two-dimensional barcode and provided to the user.

  The two-dimensional barcode generation unit 501 generates two different two-dimensional barcodes as follows.

  The two-dimensional barcode generation unit 501 requests the user to display a message on the touch panel display 10h2 so as to input two different character strings CL1 and CL2. The user inputs two different character strings CL1 and CL2 that are desired to be represented by the color two-dimensional barcode by operating the operation panel 10h.

  Then, the two-dimensional barcode generation unit 501 converts the input character strings CL1 and CL2 into monochrome (single color) two-dimensional barcodes. Thereby, two monochrome two-dimensional barcodes are generated. Hereinafter, the two generated two-dimensional barcodes may be described separately from the “first two-dimensional barcode 41” and the “second two-dimensional barcode 42”, respectively.

  Hereinafter, a case where QR (Quick Response) codes are used as the first two-dimensional barcode 41 and the second two-dimensional barcode 42 will be described as an example. QR code is a registered trademark.

  The colored cells of each of the first two-dimensional barcode 41 and the second two-dimensional barcode 42 are black cells. The colorless cells of each of the first two-dimensional barcode 41 and the second two-dimensional barcode 42 are white cells.

  The first two-dimensional barcode 41 and the second two-dimensional barcode 42 are composed of the same number of cells. Hereinafter, a case where both the first two-dimensional barcode 41 and the second two-dimensional barcode 42 are composed of M × N cells will be described as an example. The cell size of the first two-dimensional barcode 41 and the cell size of the second two-dimensional barcode 42 are the same.

  In general, the shape of the cell is a square. The number of cells is determined by the size and redundancy of data represented by a two-dimensional barcode.

  The color conversion unit 502 converts the black cell colors of the first two-dimensional barcode 41 and the second two-dimensional barcode 42 to different colors. Hereinafter, a case where the cell color of the first two-dimensional barcode 41 is converted to magenta and the cell color of the second two-dimensional barcode 42 is converted to cyan will be described as an example. Note that. The color to be converted may be determined in advance or may be specified by the user. However, it is desirable to convert the colors into distinct colors.

  By the way, as described in the “Background Art” section, conventionally, two-dimensional barcodes having different cell colors are overlapped so that cells at the same position are closely aligned with each other. Was generated. However, in this embodiment, as described below, the cells are overlapped with a slight shift.

  The cell overlap ratio determination unit 503 determines the cell overlap ratio Rk. This is the ratio of deviation between cells at the same position when the first two-dimensional barcode 41 and the second two-dimensional barcode 42 are superimposed. For example, as shown in FIG. 6, the length of one side of one cell is the length Ld, and the cell of the first two-dimensional barcode 41 and the cell of the second two-dimensional barcode 42 are separated by a distance Lb. If it is shifted (shifted) only, the cell overlap ratio Rk is Lb / Ld.

  However, the distance Lb is less than the length Ld and is not less than the minimum dot length Ls that can be read by the scan unit 10e. That is, the minimum value of the cell overlap ratio Rk is determined by the reading resolution of the scan unit 10e. For example, when a 4 × 4 pixel / 1 cell two-dimensional barcode printed by a 600 dpi printer is read by a 600 dpi scanner, a quarter of the length of one side of one cell is the length Ls. It is. The minimum cell overlap ratio Rk is “1/4”.

  In FIG. 6, the hatched cells in almost the same direction as the slash (that is, hatched hatches from the upper right to the lower left) indicate the colored cells of the first two-dimensional barcode 41. A hatched cell in almost the same direction as the backslash (that is, a hatched hatch from the upper left to the lower right) indicates a colored cell of the second two-dimensional barcode 42. The hatched cell of the mesh line indicates a portion where the colored cell of the first two-dimensional barcode 41 and the colored cell of the second two-dimensional barcode 42 overlap. The same applies to FIGS. 6, 7, 9, 10, 11, 13, 15, and 16.

  The cell overlap ratio determination unit 503 determines a cell overlap ratio Rk such that the distance Lb is equal to or greater than the length Ls and less than the length Ld. Usually, the length of half of the length Ld can be sufficiently read by the scan unit 10e. Therefore, the cell overlap ratio determination unit 503 determines, for example, “0.5” as the cell overlap ratio Rk. Alternatively, the ratio specified by the user may be determined as the cell overlap ratio Rk. Hereinafter, a case where “0.5” is used as the cell overlap ratio Rk will be described as an example.

  The color two-dimensional barcode generation unit 504 generates the color two-dimensional barcode 43 by superimposing the first two-dimensional barcode 41 and the second two-dimensional barcode 42. However, the cells at the same position are not closely aligned but can be overlapped with a slight shift as described in FIG.

  In the present embodiment, the color two-dimensional barcode generation unit 504 superimposes the second two-dimensional barcode 42 by shifting the second two-dimensional barcode 42 downward and to the right by the length Lf, as shown in FIG. The length Lf is the product of the length of one side of the cell (length Ld) and the cell overlap ratio Rk.

  The color two-dimensional barcode printing unit 505 controls the printing unit 10f so that the color two-dimensional barcode 43 is printed on paper. Thereby, a printed matter of the color two-dimensional barcode 43 is obtained.

  On the other hand, as shown in FIG. 8, the color two-dimensional barcode analysis unit 6 in FIG. 4 includes a color two-dimensional barcode acquisition unit 601, a color separation processing unit 602, a monochrome two-dimensional barcode restoration unit 603, and a text conversion processing unit. 604, a text output processing unit 605, a color correction unit 606, and the like.

  The color two-dimensional barcode acquisition unit 601 acquires the color two-dimensional barcode 43 printed on the printed material as follows. The user sets the printed material on the document feed tray of the automatic document feeder 10k. Then, a scan command is given to the image forming apparatus 1 by pressing a start button or the like.

  Then, the color two-dimensional barcode acquisition unit 601 controls the automatic document feeder 10k so that the printed material is sent to the platen glass of the scan unit 10e, and controls the scan unit 10e so that the document surface of the printed material is scanned. . As a result, the color two-dimensional barcode 43 is input to the image forming apparatus 1.

  When the color two-dimensional barcode 43 is obtained by the color two-dimensional barcode acquisition unit 601, the color separation processing unit 602 separates the color two-dimensional barcode 43 into images for each color.

  As described above, the color two-dimensional barcode 43 is obtained by superimposing the first two-dimensional barcode 41 and the second two-dimensional barcode 42. Therefore, the color two-dimensional barcode 43 includes three colors of magenta, cyan, and blue, which is a composite color of both colors. Therefore, according to the color separation processing unit 602, a magenta image 4M composed of magenta cells, a cyan image 4C composed of cyan cells, and a blue image 4B composed of blue cells are obtained.

  The monochrome two-dimensional barcode restoration unit 603 uses the image of each color obtained by the color separation processing unit 602 to convert the first two-dimensional barcode 41 and the second two-dimensional barcode 42 as shown in FIG. Restore as follows: The first two-dimensional barcode 41 is restored by superimposing the magenta image 4M and the blue image 4B and unifying the color into one color, for example, magenta. Similarly, the second two-dimensional barcode 42 is restored by superimposing the cyan image 4C and the blue image 4B and unifying the color into one color, for example, cyan. You may unify to black instead of magenta or cyan.

  The text conversion processing unit 604 analyzes each of the first two-dimensional barcode 41 and the second two-dimensional barcode 42 restored by the monochrome two-dimensional barcode restoration unit 603, thereby obtaining the first two-dimensional barcode. The character strings CL1 and CL2 shown in 41 and the second two-dimensional barcode 42 are discriminated.

  The text output processing unit 605 outputs the two character strings discriminated by the text processing unit 604, that is, the character strings CL1 and CL2 by displaying them on the touch panel display 10h2.

  By the way, in general, if copying is repeated such as copying a printed material and then copying the copied material, that is, if generation copying is repeated, the gradation difference between adjacent pixels with different colors in the image is reduced. To go.

  In the case of the color two-dimensional barcode 43, the portion where the colored cell of the first two-dimensional barcode 41 and the colored cell of the second two-dimensional barcode 42 overlap easily changes color. In particular, as shown in FIG. 10, cyan pixels are likely to change to blue. Therefore, when the color two-dimensional barcode 43 repeats the generation copy, the color of some pixels changes as shown in FIG.

  Then, the separation processing by the color separation processing unit 602 and the text conversion processing by the text conversion processing unit 604 may not work well.

  Therefore, the color correction unit 606 can analyze the character string of the color two-dimensional barcode 43 when the separation processing by the color separation processing unit 602 or the text conversion processing by the text conversion processing unit 604 does not work. Correct so that

  The color separation impossible analysis processing unit 606 includes a form detection unit 661, a color determination unit 662, a cell color replacement unit 663, and the like.

  The form detection unit 661 divides the color two-dimensional barcode 43 into areas whose upper and lower lengths and left and right lengths are both length Ld with the upper left vertex as a base point. Further, each area is expanded by four directions (Ld × Rk) from the lower right to the right, the lower right, and the lower. In this example, since the cell overlap ratio Rk is “0.5”, the cell overlap ratio Rk is expanded by four (Ld / 2) directions as shown in FIG. Hereinafter, the expanded area is referred to as “survey area BR”.

  As shown in FIG. 12B, the survey target area BR includes a first portion BRa, a second portion BRb, and a third portion BRc. The second part BRb is an expanded part of the attention area. The third part BRc is an overlapping part of the area before expansion of the area of interest and the smallest rectangular area including the third part BRc. The first portion BRa is a portion excluding both the second portion BRb and the third portion BRc in the attention area.

  And the form detection part 661 detects one of the three forms containing a colored cell shown in FIG. 13 from each investigation object area BR.

  The first form is a form in which only one colored cell of the first two-dimensional barcode 41 is arranged. That is, it is a form in which a colored cell is arranged at the upper left of the survey area BR. Hereinafter, this form is referred to as a “first form”.

  The second form is a form in which only one colored cell of the second two-dimensional barcode 42 is arranged. That is, a colored cell is arranged at the lower right of the survey target area BR. Hereinafter, this form is referred to as a “second form”.

  The third is a form in which one colored cell of the first two-dimensional barcode 41 and one colored cell of the second two-dimensional barcode 42 overlap each other. That is, it is a form in which the shape of the survey target area BR appears as it is. Hereinafter, this form is referred to as a “third form”.

  The color determination unit 662 determines the color of each pixel in each investigation target area BR. If it is either the first form or the second form, the color is unlikely to change. Therefore, the color determination unit 662 detects the color of each pixel from the investigation target area BR indicating either the first form or the second form, and detects the detected color as the color of each pixel. It is determined that According to this processing, magenta is detected from the first part BRa and the third part BRc of the survey target area BR showing the first form, white is detected from the second part BRb, and the color of each part is detected. decide. Further, cyan is detected from the second part BRb and the third part BRc of the survey target area BR showing the second form, and white is detected from the first part BRa, and the color of each part is determined.

  If the scanned print is not a generation copy print, three colors of magenta, cyan, and blue should be detected from the survey area BR of the third form. However, if generation copying is repeated, as described above, these colors may not be detected properly. Therefore, the color determination unit 662 determines the color of the survey target area BR by the following method.

  As shown in FIG. 14 (A), the color discriminating unit 662 performs other investigations of the first form from any one of directly above, directly below, directly to the right, and to the right of the first portion BRa of the investigation target area BR. A colored cell in the target area BR is searched. Then, it is determined that the color of the searched cell is the color of the first portion BRa. When a plurality of cells are found, it is desirable that the color of the isolated cell, that is, the color of the cell surrounded by the colorless (white) cell, be the color of the first portion BRa.

  Similarly, as shown in FIG. 14 (b), the color determination unit 662 has the second form from any one of directly above, directly below, directly to the left, and directly to the right of the second portion BRb of the survey target area BR. A colored cell in another survey area BR is searched. Then, the color of the searched cell is determined to be the color of the second portion BRb. Further, it is determined that the color of the third part BRc is a composite color of the colors detected from the first part BRa and the second part BRb.

  The cell color replacement unit 663 corrects the color two-dimensional barcode 43 by replacing the color of each pixel in each investigation target area BR with the color determined by the color determination unit 662.

  The color two-dimensional barcode 43 is corrected by the above processing by each unit of the color correction unit 606.

  Thereafter, the color separation processing unit 602 and the monochrome two-dimensional barcode restoration unit 603 perform the processing described with reference to FIG. 9 on the color two-dimensional barcode 43 corrected by the color correction unit 606. The first two-dimensional barcode 41 and the second two-dimensional barcode 42 are restored. Then, the text processing unit 604 acquires the character strings CL1 and CL2 by analyzing the first two-dimensional barcode 41 and the second two-dimensional barcode 42, and the text output processing unit 605 displays the character string CL1. And CL2 are output.

  According to the present embodiment, the first two-dimensional barcode 41 and the second two-dimensional barcode 42 are slightly shifted so that the cells do not completely overlap each other, and are overlapped, so that the color two-dimensional barcode 43 Was generated. Therefore, even if the reproducibility of some colored cells in the color two-dimensional barcode 43 is lowered, the colors of the some colored cells are determined based on other colored cells, and the first The two-dimensional barcode 41 and the second two-dimensional barcode 42 can be separated.

  In the above embodiment, magenta is used as the color of the colored cell of the first two-dimensional barcode 41, and cyan is used as the color of the colored cell of the second two-dimensional barcode 42. It may be used. For example, yellow and cyan may be used.

  In the above-described embodiment, the color two-dimensional barcode 43 is generated by shifting the second two-dimensional barcode 42 by one half of the cell in the lower right direction with respect to the first two-dimensional barcode 41. However, it may be generated by shifting in another direction.

  FIG. 15 is a diagram illustrating a modified example of the method for generating the color two-dimensional barcode 43. FIG. 16 is a diagram showing a modification of the method for detecting the first two-dimensional barcode 41 and the second two-dimensional barcode 42.

  In the above-described embodiment, the color two-dimensional barcode 43 is generated by shifting the entire second two-dimensional barcode 42, but only the position detection patterns (so-called large eyeballs) at the three corners are not shifted. Alternatively, the color two-dimensional barcode 43 may be generated. That is, the three position detection patterns of the first two-dimensional barcode 41 and the three position detection patterns of the second two-dimensional barcode 42 are completely matched, cells other than the position detection pattern are shifted, and the color A two-dimensional barcode 43 may be generated. In this case, each unit of the color two-dimensional barcode providing unit 5 shown in FIG. 5 and each unit of the color two-dimensional barcode analyzing unit 6 shown in FIG. 8 perform processing as follows.

  The two-dimensional barcode generation unit 501 and the cell overlap ratio determination unit 503 perform the processing as described above.

  As described above, the color conversion unit 502 basically converts the colored cell color of the first two-dimensional barcode 41 and the colored color of the second two-dimensional barcode 42 into different colors. That is, for example, the former is converted to magenta and the latter is converted to cyan. However, the color of the cells constituting the position detection pattern is left black for both the first two-dimensional barcode 41 and the second two-dimensional barcode 42.

  The color two-dimensional barcode generation unit 504 detects three position detection patterns from the second two-dimensional barcode 42. Then, the cells constituting the three position detection patterns are not moved, and the other cells are shifted downward and right by the length Lf, respectively. Then, as shown in FIG. 15, the color two-dimensional barcode 43 ′ is generated by superimposing the shifted second two-dimensional barcode 42 on the first two-dimensional barcode 41.

  The color two-dimensional barcode printing unit 505 controls the printing unit 10f and the like so that the generated color two-dimensional barcode 43 'is printed on paper.

  Next, the process of detecting the first two-dimensional barcode 41 and the second two-dimensional barcode 42 from the color two-dimensional barcode 43 'is performed according to the procedure shown in FIG.

  When the color two-dimensional barcode acquisition unit 601 acquires the color two-dimensional barcode 43 ′ from the document (# 11 in FIG. 16), the color separation processing unit 602 converts the color two-dimensional barcode 43 ′ for each color as described above. (# 12). However, as a result of the separation, not only the magenta image 4M ′, the cyan image 4C ′, and the blue image 4B ′ but also a black image 4K ′ composed of black cells is obtained. The black image 4K ′ is an image representing three position detection patterns. Therefore, three position detection patterns can be detected by the processing of the color separation processing unit 602.

  The monochrome two-dimensional barcode restoration unit 603 uses the magenta image 4M ′, the cyan image 4C ′, and the blue image 4B ′ in the same manner as in the above-described embodiment, and uses the first two-dimensional barcode 41 and A portion other than the position detection pattern of the second two-dimensional barcode 42 is restored (# 13).

  Then, the monochrome two-dimensional barcode restoring unit 603 restores all parts of the first two-dimensional barcode 41 and the second two-dimensional barcode 42 by superimposing the black image 4K ′ on each restored part (#). 14). Further, when the color two-dimensional barcode 43 ′ is generated, the relative positions of the position detection pattern of the second two-dimensional barcode 42 and the other portions are changed. Therefore, the monochrome two-dimensional barcode restoration unit 603 adjusts the relative positions of the two based on the QR code standard.

  Thereafter, the text processing unit 604 obtains character strings CL1 and CL2 from the first two-dimensional barcode 41 and the second two-dimensional barcode 42, and the text output processing unit 605 outputs the character strings CL1 and CL2. . When the processing by the color separation processing unit 602 or the text conversion processing unit 604 is not successful, the color correction unit 606 corrects the color of the color two-dimensional barcode 43 ′.

  Note that the color two-dimensional barcode 43 ′ may be generated without shifting not only the three position detection patterns but also a group of cells (so-called small eyeballs) constituting an alignment pattern near the center. Whether or not to shift the position detection pattern or the like may be selected by the user every time the color two-dimensional barcode is generated, or may be set in the image forming apparatus 1 in advance.

  In the above-described embodiment, the common cell overlap ratio Rk is used for the vertical and horizontal shifts. However, the cell overlap ratio Rk may be set differently in the vertical and horizontal directions.

  For each position, it is checked whether the colored cells of the first two-dimensional barcode 41 and the colored cells of the second two-dimensional barcode 42 overlap each other. If the overlapping ratio is less than a certain value, The color two-dimensional barcode 43 may be generated by overlapping the first two-dimensional barcode 41 and the second two-dimensional barcode 42 without shifting. Hereinafter, this ratio is referred to as “colored cell overlapping ratio Rc”.

  FIG. 17 is a diagram illustrating an example of a flow of processing for generating the color two-dimensional barcode 43. FIG. 18 is a flowchart for explaining an example of the flow of processing for detecting the first two-dimensional barcode 41 and the second two-dimensional barcode 42.

  In the above-described embodiment, the functions shown in FIG. 5 and FIG. 8 are realized by hardware modules, but some or all of the functions may be realized by causing the CPU 10a to execute a computer program. In this case, a first program that performs processing according to the procedure shown in FIG. 17 may be prepared as a program for providing the color two-dimensional barcode 43 and executed by the CPU 10a. In addition, a second program that performs processing according to the procedure shown in FIG. 18 may be prepared as a program for analyzing the color two-dimensional barcode 43 and executed by the CPU 10a.

  Here, processing by the first program and the second program will be described with reference to FIGS. 17 and 18.

  The image forming apparatus 1 accepts input of two character strings CL1 and CL2 collectively represented in one color two-dimensional barcode (# 701 in FIG. 17). Then, the character string CL1 is converted into the first two-dimensional barcode 41, and the character string CL2 is converted into the second two-dimensional barcode 42 (# 702). Further, the colored cells of the first two-dimensional barcode 41 and the second two-dimensional barcode 42 are changed to different colors, for example, magenta and cyan (# 703). Then, the colored cell overlap ratio Rc is calculated (# 704).

  If the colored cell overlap ratio Rc is less than a certain value (No in # 705), the image forming apparatus 1 shifts the first two-dimensional barcode 41 and the second two-dimensional barcode 42 as usual. A color two-dimensional barcode is generated by superimposing without performing (# 706). Then, the generated color two-dimensional barcode is printed (# 713).

  On the other hand, if the colored cell overlap ratio Rc is equal to or greater than a certain value (Yes in # 705), the image forming apparatus 1 sets the direction and length for shifting the second two-dimensional barcode 42 (# 707). ).

  As described with reference to FIG. 15, when the position detection patterns are overlapped without being shifted (No in # 708), the image forming apparatus 1 uses each of the first two-dimensional barcode 41 and the second two-dimensional barcode 42. The color of the position detection pattern is converted to black (# 709). Cells other than the position detection pattern of the second two-dimensional barcode 42 are shifted based on the setting in step # 706 (# 710). Then, a color two-dimensional barcode 43 'is generated by superimposing the first two-dimensional barcode 41 and the second two-dimensional barcode 42 (# 712) and printed (# 713).

  As described with reference to FIG. 7, when the entire image including the position detection pattern is shifted and overlapped (Yes in # 708), the image forming apparatus 1 applies the entire second two-dimensional barcode 42 based on the setting in step # 706. To shift (# 711). Then, a color two-dimensional barcode 43 'is generated by superimposing the first two-dimensional barcode 41 and the second two-dimensional barcode 42 (# 712) and printed (# 713).

  Thereafter, when the user sets a printed matter on which the color two-dimensional barcode 43 is printed on the image forming apparatus 1 and inputs a predetermined command, the image forming apparatus 1 analyzes the character string indicated by the color two-dimensional barcode 43. Processing is performed as follows.

  The image forming apparatus 1 scans the set printed material and reads the color two-dimensional barcode 43 (# 721 in FIG. 18). Further, a position detection pattern is detected from the color two-dimensional bar code 43 (# 722), and the form (see FIG. 13) for each investigation target area BR is detected (# 723).

  If no third form is detected (Yes in # 724), the image forming apparatus 1 uses the conventional method to change the color two-dimensional barcode 43 to the first two-dimensional barcode 41 and the second two-dimensional barcode. The dimension barcode 42 is restored, and the character strings CL1 and CL2 shown in each are analyzed (# 725) and output (# 734).

  If even one of the third forms is detected (No in # 724), the image forming apparatus 1 generates the color two-dimensional barcode 43 by shifting and superimposing the two two-dimensional barcodes. (# 726). Then, processing is performed as follows.

  The image forming apparatus 1 separates the color two-dimensional barcode 43 into images for each color (# 727). If the separation is successful (Yes in # 728), the first two-dimensional barcode 41 and the second two-dimensional barcode 42 are restored based on each color image (# 730). If the separation is not successful (No in # 728), the color of the color two-dimensional barcode 43 is corrected by the method described in FIG. 14 (# 729). Then, the corrected color two-dimensional barcode 43 is separated into images for each color (# 727), and the first two-dimensional barcode 41 and the second two-dimensional barcode 42 are restored based on the image of each color. (# 730).

  The image forming apparatus 1 analyzes the first two-dimensional barcode 41 and the second two-dimensional barcode 42, specifies the character strings CL1 and CL2 (# 732), and outputs them. However, if there is a deviation between the position detection pattern and the other cells in at least one of the first two-dimensional barcode 41 and the second two-dimensional barcode 42 (Yes in # 731), the deviation is determined. After correction (# 732), the character string is analyzed and output (# 733, # 734).

  In the above-described embodiment, a color two-dimensional barcode is generated by superimposing two two-dimensional barcodes. However, the present invention generates a color two-dimensional barcode by superimposing three or more two-dimensional barcodes. It can also be applied to cases. When a color two-dimensional barcode is generated by superimposing N two-dimensional barcodes, for example, “1 / N” may be used as the ratio Rk.

  In the above-described embodiment, the case where a QR code is used as a two-dimensional bar code has been described as an example. However, the present invention can also be applied to a case where a two-dimensional bar code of another standard is used.

  In addition, the configuration of the entire image forming apparatus 1 or each unit, the processing content, the processing order, the configuration of the two-dimensional barcode, and the like can be appropriately changed in accordance with the spirit of the present invention.

Claims (8)

Two-dimensional barcode acquisition means for acquiring a plurality of two-dimensional barcodes having different colors of colored cells as a plurality of two-dimensional barcodes;
A color two-dimensional barcode generating means for generating a color two-dimensional barcode by overlapping the plurality of two-dimensional barcodes by shifting a cell at the same position by a fixed distance; and
A color two-dimensional barcode output means for outputting the color two-dimensional barcode;
A color two-dimensional barcode generating apparatus comprising: The color two-dimensional barcode generation means generates the color two-dimensional barcode by overlapping the plurality of two-dimensional barcodes without shifting the cells constituting the position detection pattern or the alignment pattern.
The color two-dimensional barcode generation apparatus according to claim 1. The color two-dimensional barcode generation means generates the color two-dimensional barcode using black as the color of the cells constituting the position detection pattern or alignment pattern.
The color two-dimensional barcode generation apparatus according to claim 2. Color two-dimensional barcode acquisition means for acquiring a color two-dimensional barcode generated by overlapping a plurality of two-dimensional barcodes having different colors of colored cells by shifting a cell at the same position by a certain distance. When,
Shape detection means for detecting the shape of a colored pixel group consisting of colored pixels in the area for each of the plurality of cell areas that are shifted and overlapped by the predetermined distance in the color two-dimensional barcode;
When the shape detected from the area is the same as the shape of one cell, the color of the colored pixel group in the area is detected, and the color of the colored pixel group is determined to be the detected color. When the shape is the same as the shape obtained by shifting and overlapping a plurality of cells, each cell portion corresponding to one cell in the colored pixel group in the area is directly above, directly below, and true. Detects the color of another cell located on the left or right side, determines that the color of the cell part that does not overlap with the other cell part is the detected color, and overlaps with the other cell part Color discriminating means for discriminating that the color of the part is a composite color of the color detected for each of the cell part and the other cell part;
Two-dimensional barcode identification means for identifying each of the plurality of two-dimensional barcodes based on the color of each pixel of the color two-dimensional barcode determined by the color determination means;
A color two-dimensional barcode reader characterized by comprising: As a plurality of two-dimensional barcodes, obtain a plurality of two-dimensional barcodes with different colors of colored cells,
A plurality of two-dimensional barcodes are generated by superimposing the cells at the same position while shifting them by a certain distance to generate a color two-dimensional barcode,
Outputting the color two-dimensional barcode;
A color two-dimensional barcode generation method characterized by the above. Obtain a color two-dimensional barcode generated by overlapping a plurality of two-dimensional barcodes with different colors of colored cells by shifting the cells at the same position by a fixed distance,
Detecting a shape of a colored pixel group composed of colored pixels in the area for each of the plurality of cell areas that are overlapped with a certain distance in the color two-dimensional barcode;
When the shape detected from the area is the same as the shape of one cell, the color of the colored pixel group in the area is detected, and the color of the colored pixel group is determined to be the detected color. When the shape is the same as the shape obtained by shifting and overlapping a plurality of cells, each cell portion corresponding to one cell in the colored pixel group in the area is directly above, directly below, and true. Detects the color of another cell located on the left or right side, determines that the color of the cell part that does not overlap with the other cell part is the detected color, and overlaps with the other cell part It is determined that the color of the part is a composite color of the color detected for each of the cell part and the other cell part,
Identifying each of the plurality of two-dimensional barcodes based on the determined color of each pixel of the color two-dimensional barcode,
A color two-dimensional barcode reading method characterized by the above. As a plurality of two-dimensional barcodes, let the computer execute a process of obtaining a plurality of two-dimensional barcodes with different colors of colored cells,
By causing the computer to execute a process of generating a color two-dimensional barcode by overlapping the plurality of two-dimensional barcodes by shifting the cells at the same position by a fixed distance,
Causing the computer to execute a process of outputting the color two-dimensional barcode;
A computer program characterized by that. A computer executes a process for obtaining a color two-dimensional barcode generated by overlapping a plurality of two-dimensional barcodes having different colors of colored cells by shifting a plurality of two-dimensional barcodes at the same position by a certain distance,
In the color two-dimensional barcode, the computer is caused to execute processing for detecting a shape of a colored pixel group composed of colored pixels in the area for each of the plurality of cell areas that are shifted by a certain distance and overlap each other. ,
When the shape detected from the area is the same as the shape of one cell, the color of the colored pixel group in the area is detected, and the color of the colored pixel group is determined to be the detected color. When the shape is the same as the shape obtained by shifting and overlapping a plurality of cells, each cell portion corresponding to one cell in the colored pixel group in the area is directly above, directly below, and true. Detects the color of another cell located on the left or right side, determines that the color of the cell part that does not overlap with the other cell part is the detected color, and overlaps with the other cell part Causing the computer to execute a process of determining that the color of the part is a composite color of the color detected for each of the cell part and the other cell part,
Based on the determined color of each pixel of the color two-dimensional barcode, the computer is caused to execute a process of specifying each of the plurality of two-dimensional barcodes.
A computer program characterized by that.

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