JP2007257360A - Two-dimensional code, two-dimensional code reader and two-dimensional code-reading program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-dimensional code capable of storing a greater amount of data without increasing outer size. <P>SOLUTION: This two-dimensional code has: a symbol showing a position that is a reference when read; and a data cell expressing information by a distribution pattern of the cell. The data cell includes one or more colored unit cells each having a color corresponding to one of a threshold values preset to at least three stages. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a two-dimensional code, a two-dimensional code reading device, and a two-dimensional code reading program used in the two-dimensional code reading device.

Conventionally, a one-dimensional code such as a bar code has been used, but in recent years, since a larger amount of data can be stored, a two-dimensional code has begun to be used.

The two-dimensional code responds to a request to store more data. Usually, the larger the amount of data to be stored, the larger the size (outer shape) of the entire two-dimensional code. In addition, when a large amount of data is stored while maintaining the size of the entire two-dimensional code as it is, it is necessary to reduce each data area (for example, unit cell), which is impossible or difficult to read by the reading device. There was a problem that it would be too small.

In particular, a method of acquiring data from a two-dimensional code using a camera provided in a mobile phone is often used in recent years, but if the two-dimensional code is too large, it must be imaged separately, There was a problem that it did not look good. In addition, when each data area is small, there is a problem that a two-dimensional code cannot be recognized and data cannot be obtained.

Conventionally, a two-dimensional code having a rectangular code pattern composed of a plurality of macro modules, in which a data code word and a cluster number for determining the position of the macro module are stored for each macro module (See, for example, Patent Document 1).

JP 2005-267598 A

When the two-dimensional code is read, it is usually read after the position serving as a reference is recognized by the reading device. Therefore, the data area can be secured by reducing the positioning area. However, in the two-dimensional barcode described in Patent Document 1, the cluster number is stored for each macro module to reduce the positioning area for reading as a whole two-dimensional barcode. The unit module in which the cluster number is stored is small, and since the cluster number is stored in all the macro modules, it cannot be said that the positioning area is reduced as a whole, and the data area is secured. It's hard to say that you can.

Further, in the two-dimensional barcode described in Patent Document 1, data is binarized by using a deep color (for example, black) and a shallow color (for example, white) and stored as a data code word. Furthermore, the demand for storing more data in the area per unit was not fulfilled.

The present invention has been made in view of the above-described problems, and an object of the present invention is to read a two-dimensional code capable of storing more data without increasing the outer shape and the two-dimensional code. The object is to provide a two-dimensional code reader.

In order to achieve the above object, the present invention provides the following.
(1) a symbol indicating a reference position for reading;
A two-dimensional code comprising data cells representing information by a cell distribution pattern,
The two-dimensional code characterized in that the data cell includes one or a plurality of colored unit cells having a color corresponding to one of threshold values preset in three or more stages. .

According to the invention of (1), a symbol indicating a reference position at the time of reading and a data cell expressing information by a cell distribution pattern are provided, and the data cell is previously divided into three or more stages. One or a plurality of colored unit cells having a color corresponding to one of the set threshold values are included. Therefore, more data can be stored in each unit cell than when data is binarized, and more data can be stored without increasing the outer shape of the entire two-dimensional code. It becomes.
In addition, when a configuration in which additional information is stored in the colored unit cell portion and main information is stored in the other unit cell (for example, unit cell expressed in black and white) portions, Even if a two-dimensional code reader (two-dimensional code reader for binarizing the color of each unit cell to read data) is used, at least main information can be read.

Furthermore, the present invention provides the following.
(2) Imaging means capable of imaging the two-dimensional code described in (1) above;
Symbol position detection means for detecting the symbol position of the two-dimensional code imaged by the imaging means;
Data cell position detecting means for detecting the position of the data cell based on the symbol position detected by the symbol position detecting means;
Detecting means for detecting a threshold value assigned to each unit cell of the data cell whose position is detected by the data cell position detecting means;
A two-dimensional code reading apparatus comprising: reading means for reading information of a two-dimensional code based on a threshold value of each unit cell detected by the detecting means.

According to the invention of (2), the symbol position of the captured two-dimensional code is detected, the position of the data cell is detected based on the detected symbol position, and the threshold assigned to each unit cell of the data cell is detected. A value is detected, and information on the two-dimensional code is read based on the detected threshold value of each unit cell. Here, the threshold value is preset in a plurality of stages of 3 or more. Therefore, for example, it is possible to read a two-dimensional code including a colored unit cell that is not larger than a two-dimensional code composed of only monochrome colors and stores more data.

Furthermore, the present invention provides the following.
(3) imaging means capable of imaging the two-dimensional code described in (1) above;
A two-dimensional code reader with
Symbol position detection means for detecting a symbol position of a two-dimensional code imaged by the imaging means;
Data cell position detecting means for detecting the position of the data cell based on the symbol position detected by the symbol position detecting means;
Detecting means for detecting a threshold value assigned to each unit cell of the data cell whose position is detected by the data cell position detecting means; and
A two-dimensional code reading program which functions as a reading means for reading information of a two-dimensional code based on a threshold value of each unit cell detected by the detecting means.

According to the invention of (3), the symbol position of the captured two-dimensional code is detected, the position of the data cell is detected based on the detected symbol position, and the threshold assigned to each unit cell of the data cell is detected. A value is detected, and information on the two-dimensional code is read based on the detected threshold value of each unit cell. Here, the threshold value is preset in a plurality of stages of 3 or more. Therefore, for example, it is possible to read a two-dimensional code including a colored unit cell that is not larger than a two-dimensional code composed of only monochrome colors and stores more data.

According to the present invention, it is possible to provide a two-dimensional code that can store more data without increasing the outer shape, and a two-dimensional code reader that reads the two-dimensional code.

FIG. 1 is a diagram showing an example of a two-dimensional code according to the present invention.
The two-dimensional code 92 has a rectangular shape, and includes a symbol indicating a reference position for reading and a data cell 102 that expresses information by a cell distribution pattern. A symbol indicating a position serving as a reference for reading is composed of positioning symbols 100A, 100B, and 100C arranged at three corners of the two-dimensional code 92, and a positioning auxiliary symbol 101 arranged at the lower right of FIG. Has been.

The positioning symbol 100 (100A, 100B, 100C) is used for detecting the position of the data cell 102, as will be described in detail later. The positioning auxiliary symbol 101 is used for the data cell 102 after the position detection. It is used for correcting distortion and the like. The data cell 102 includes a plurality of unit cells 103, and includes a normal unit cell made of white or black and a colored unit cell made of a color other than white or black.

In the present embodiment, the case where the colored unit cell is any one of red, blue, and yellow will be described. However, in the present invention, the colored unit cell is not limited to these colors.
Moreover, although this embodiment demonstrates the case where there are two or more colored unit cells, in this invention, one may be sufficient.
Further, in the present embodiment, a case where the data cell 102 includes a normal unit cell will be described. However, in the present invention, all of the data cells may be composed of colored unit cells.

Each color of the unit cell 103 is set to have a predetermined brightness. In the present embodiment, a case where the brightness is set to increase in the order of black, red, blue, yellow, and white will be described, but the present invention is not limited to this.

FIG. 2 is a perspective view schematically showing an example of a mobile phone which is an embodiment of the two-dimensional code reader according to the present invention, and FIG. 3 is a block diagram showing an internal configuration of the mobile phone shown in FIG. FIG.

In the present embodiment, the case where the two-dimensional code reading device according to the present invention is a mobile phone will be described. However, the present invention is not limited to this, and may be a device dedicated to two-dimensional code reading, for example.

The cellular phone 10 includes an operation unit 12, a liquid crystal panel 14, a CCD camera 16, a radio unit 18, an audio circuit 20, a speaker 22, a microphone 24, a transmission / reception antenna 26, a nonvolatile memory 28, a microcomputer 30, and a secondary battery 32. ing.

The radio unit 18 is controlled by the microcomputer 30 and transmits / receives to / from the base station using radio waves as a medium through the transmitting / receiving antenna 26. The audio circuit 20 outputs the reception signal output from the wireless unit 18 through the microcomputer 30 to the speaker 22 and outputs the audio signal output from the microphone 24 to the wireless unit 18 through the microcomputer 30 as a transmission signal.

The speaker 22 converts the reception signal output from the audio circuit 20 into reception audio and outputs it, and the microphone 24 converts the transmission audio emitted from the operator into an audio signal and outputs it to the audio circuit 20.
The CCD camera 26 can image a subject such as a two-dimensional code 92, and image data obtained by imaging is stored in the nonvolatile memory 28. In the present embodiment, a case where a CCD camera is used as the imaging unit will be described. However, the imaging unit in the present invention is not particularly limited, and examples thereof include a CMOS sensor camera.

The liquid crystal panel 14 displays, for example, characters input via the operation unit 12, images obtained by imaging with the CCD camera 16, mail texts and images received via the transmission / reception antenna 26, and the like.

The secondary battery 32 supplies power to each circuit. The microcomputer 30 includes a CPU, a ROM, and a RAM, and performs, for example, incoming / outgoing calls processing, e-mail creation / transmission processing, Internet processing, and the like. Note that transmission / reception of electronic mail and transmission / reception of data via the Internet are performed by the microcomputer 30 via the wireless unit 18 and the transmission / reception antenna 26.

The nonvolatile memory 28 stores, in a nonvolatile manner, various data and various programs such as e-mail data input via the operation unit 12 and image data obtained by the CCD camera 16 imaging the two-dimensional code 92. To do.

The nonvolatile memory 28 stores a two-dimensional code reading program for acquiring data from the two-dimensional code 92.
In the present embodiment, a case where the two-dimensional code reading program is stored in advance (preinstalled) in the nonvolatile memory 28 will be described. However, in the present invention, the two-dimensional code reading program is, for example, from a server or the like. It is good also as acquiring from the outside, such as downloading via the internet.

The microcomputer 30 functions as follows (A) to (D) by reading and executing a two-dimensional code reading program from the nonvolatile memory 28.

(A) The microcomputer 30 detects the positioning symbol 100 of the two-dimensional code 92 imaged by the CCD camera 16.
(B) The microcomputer 30 detects the position of the data cell 102 based on the detected positioning symbol 100.
(C) The microcomputer 30 detects a threshold value assigned to each unit cell 103 of the data cell 102 where the position is detected.
(D) The microcomputer 30 reads the information of the two-dimensional code based on the detected threshold value of each unit cell 103.

FIG. 4 is a flowchart showing a two-dimensional code recognition process performed in the mobile phone.
First, the microcomputer 30 included in the mobile phone 10 drives the CCD camera 16 as an imaging unit based on an instruction input via the operation unit 12, and images the two-dimensional code 92 (step S10).

Next, the microcomputer 30 performs binarization processing on the image data obtained in step S10, and replaces each dot with “0” or “1” (step S11).

Next, the microcomputer 30 creates an envelope (surrounding line) that surrounds the peripheral outline of the two-dimensional code 92 (step S12). In this process, the microcomputer 30 connects a plurality of cells existing on the outer periphery of the binarized image to create an envelope surrounding the two-dimensional code (image). Specifically, the black cells existing on the outermost periphery are found and the adjacent black cells are sequentially connected.

Next, in step S <b> 13, the microcomputer 30 extracts the four vertices of the two-dimensional code 92. In this process, the microcomputer 30 investigates the interior angle of the polygon surrounded by the envelope. Since the inner angle of the corner of the two-dimensional code 92 shows a value of approximately 90 degrees, four vertices are extracted from this.

Next, in step S14, the microcomputer 30 detects the positioning symbol 100A, the positioning symbol 100B, and the positioning symbol 100C based on the positions of the four vertices. When executing this processing, the microcomputer 30 functions as a symbol position detecting means for detecting the position of the positioning symbol 100.

Next, in step S <b> 15, the microcomputer 30 detects the position of the data cell 102 based on the position of the positioning symbol 100. When this processing is executed, the microcomputer 30 functions as a data cell position detecting unit that detects the position of the data cell 102 based on the position of the positioning symbol 100.
Note that the processing in steps S12 to S15 is executed using the binarized data, and the processing in step S16 is performed using the image data obtained in step S10 (before the binarization processing). Done.

Next, the microcomputer 30 performs gray processing on the data cell 102 whose position has been detected, and replaces it with black and white density gradation (step S16), thereby generating multi-value matrix data (step S17). At this time, with reference to the positioning auxiliary symbol 101, distortion or the like is corrected for the data cell 102 after position detection, and multi-value matrix data is generated.

Here, a method for generating multi-value matrix data will be described.
FIG. 5 is a diagram for explaining a method of generating multi-value matrix data.
In FIG. 5, black, red, blue, yellow, and white unit cells are shown in order from the left, and the vertical axis of the graph indicates the reflectance of each unit cell.
The black unit cell has the lowest reflectance and is lower than the first threshold value. Therefore, in this case, the value indicated by the unit cell is determined to be “0”.
The red unit cell has the second lowest reflectance, which is higher than the first threshold but lower than the second threshold. Therefore, in this case, the value indicated by the unit cell is determined to be “1”.
The blue unit cell has the third lowest reflectance, which is higher than the second threshold value but lower than the third threshold value. Therefore, in this case, the value indicated by the unit cell is determined to be “2”.
Further, the yellow unit cell has the fourth lowest reflectance, which is higher than the third threshold value but lower than the fourth threshold value. Therefore, in this case, the value indicated by the unit cell is determined to be “3”.
Further, the white unit cell has the highest reflectance and is higher than the fourth threshold value. Therefore, in this case, the value indicated by the unit cell is determined to be “4”.
The above processing is performed for each unit cell and digitized to generate multi-value matrix data. When executing the process of step S <b> 17, the microcomputer 30 functions as a detection unit that detects a threshold value assigned to each unit cell of the data cell 102.

Next, the microcomputer 30 decodes the multi-value matrix data (step S18) and generates data (step S19). Thereafter, this subroutine is terminated.
As a result, the decoded data is displayed on the liquid crystal panel 14 of the mobile phone 10.

In the present embodiment, the processing up to positioning (the processing from step S12 to step S15) has been described using binarized data and using multi-valued data after positioning, but in the present invention, After image capturing, first, multilevel processing may be performed, and then processing such as positioning may be performed.

In the above-described embodiment, a case has been described in which multi-value matrix data is generated after gray processing is performed on the data cell 102 and replaced with black and white density gradation. In the present invention, gray processing is performed. First, the color of each unit cell is color-separated according to a predetermined standard (for example, three primary colors of cyan, magenta, and yellow) to calculate the gray scale of each color component, and the multi-value matrix data is calculated by this gray scale. It may be generated. Hereinafter, the two-dimensional code recognition process in this case will be described.

FIG. 6 is a flowchart showing a two-dimensional code recognition process according to another embodiment performed in the mobile phone.
Since the processing from step S40 to step S45 is the same as that from step S10 to step S15 shown in FIG. 4, the description thereof is omitted here.

In step S46, the microcomputer 30 performs a color conversion process on the data cell 102 whose position has been detected, and converts RGB (red, green, blue) original image data (image data of the data cell 102) into CMY (cyan). , Magenta, yellow). By this color conversion processing, the grayscale for each RGB when imaged is replaced with the grayscale for each CMY. In the following, a case where the density gradation of each color of CMY is two gradations will be described, but the density gradation of each color is not limited to this example.

Next, in step S47, the microcomputer 30 generates multi-value matrix data based on density gradations for each CMY. Here, a method for generating multi-value matrix data will be described.

FIG. 7 shows a threshold value determination table.
As shown in FIG. 7, threshold values are associated with combinations of CMY gradations. For example, a threshold value “0” is associated with a combination of C gradation “0”, M gradation “0”, and Y gradation “0”. For example, a threshold value “3” is associated with a combination of “0” for C, “1” for M, and “1” for Y.
In step S46, the microcomputer 30 refers to the threshold value determination table and digitizes each unit cell to generate multi-value matrix data.

Next, the microcomputer 30 decodes the multi-value matrix data (step S48) and generates data (step S49). Thereafter, this subroutine is terminated. As a result, the decoded data is displayed on the liquid crystal panel 14 of the mobile phone 10.

As described above, according to the two-dimensional code 92, a symbol (positioning symbol 100, positioning auxiliary symbol 101) indicating a position serving as a reference at the time of reading and a data cell 102 expressing information by a cell distribution pattern are provided. The data cell 102 is configured to include a plurality of colored unit cells having colors corresponding to any of threshold values preset in three or more stages. Accordingly, more data can be stored in each unit cell 103 than when data is binarized, and more data can be stored without increasing the outer shape of the entire two-dimensional code. It becomes possible.

Further, according to the mobile phone 10 using the two-dimensional code reading program, the position of the positioning symbol 100 of the captured two-dimensional code 92 is detected, and the position of the data cell 102 is determined based on the detected position of the positioning symbol 100. The threshold value assigned to each unit cell 103 of the data cell 102 is detected, and the information of the two-dimensional code 92 is read based on the detected threshold value of each unit cell 103. Here, the threshold value is preset in a plurality of stages of 3 or more. Therefore, for example, it is possible to read a two-dimensional code including a colored unit cell that is not larger than a two-dimensional code composed of only monochrome colors and stores more data.

The two-dimensional code in the present invention is not limited to the two-dimensional code 92 as described above, and may be the following two-dimensional code.

FIG. 8 is a diagram showing an example of another two-dimensional code according to the present invention.
The two-dimensional code 122 has a substantially rectangular shape, and includes a symbol indicating a reference position for reading and a data cell 142 that expresses information by a cell distribution pattern. A symbol indicating a position serving as a reference for reading is composed of positioning symbols 140A, 140B, and 140C arranged at three corners of the two-dimensional code 122, and a positioning auxiliary symbol 141 arranged at the lower right of FIG. Has been.

The positioning symbol 140 (140A, 140B, 140C) is used to detect the position of the data cell 122, and the positioning auxiliary symbol 141 is used to correct distortion and the like for the data cell 142 after position detection. It is used for. The data cell 142 is composed of a plurality of unit cells 143, and the unit cell inside the envelope (surrounding line) 145 surrounding the peripheral outline of the two-dimensional code 122 is a normal unit cell made of white or black. The unit cell outside the envelope 145 is a colored unit cell made of a color other than white or black.

According to the two-dimensional code 122, additional information is stored in the colored unit cell (unit cell outside the envelope 145) portion, and other unit cells (unit cells inside the envelope 145) are stored. When the main information is stored in the portion, at least the main two-dimensional code reader (two-dimensional code reader that reads data by binarizing the color of each unit cell) is used. It may be possible to read information.

The embodiment of the present invention has been described above, but only specific examples are illustrated, and the present invention is not particularly limited. The specific configuration of each unit and the like can be appropriately changed in design. The effects described in the embodiments of the present invention are only the most preferable effects resulting from the present invention, and the effects of the present invention are limited to those described in the embodiments of the present invention. is not.

It is a figure which shows an example of the two-dimensional code which concerns on this invention. It is a perspective view showing typically an example of a cellular phone which is one embodiment of a two-dimensional code reading device concerning the present invention. FIG. 3 is a block diagram showing an internal configuration of the mobile phone shown in FIG. 2. It is a flowchart which shows the two-dimensional code recognition process performed in a mobile telephone. It is a figure for demonstrating the production | generation method of multi-value matrix data. It is a flowchart which shows the two-dimensional code recognition process which concerns on other embodiment performed in a mobile telephone. It is a figure which shows a threshold value determination table. It is a figure which shows an example of the other two-dimensional code which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Mobile phone 12 Operation part 14 Liquid crystal panel 18 Radio | wireless part 28 Non-volatile memory 30 Microcomputer 32 Secondary battery 92, 122 Two-dimensional code 100 (100A, 100B, 100C), 140 (140A, 140B, 140C) Positioning symbol 101, 141 Positioning auxiliary symbol 102, 142 Data cell 103, 143 Unit cell 145 Envelope

Claims (3)

A symbol indicating a reference position for reading;
A two-dimensional code comprising data cells representing information by a cell distribution pattern,
The two-dimensional code, wherein the data cell includes one or a plurality of colored unit cells having a color corresponding to one of threshold values preset in three or more stages. . Imaging means capable of imaging the two-dimensional code according to claim 1;
Symbol position detection means for detecting a symbol position of a two-dimensional code imaged by the imaging means;
Data cell position detecting means for detecting the position of the data cell based on the symbol position detected by the symbol position detecting means;
Detecting means for detecting a threshold value assigned to each unit cell of the data cell whose position is detected by the data cell position detecting means;
A two-dimensional code reading apparatus comprising: reading means for reading information of a two-dimensional code based on a threshold value of each unit cell detected by the detecting means. A two-dimensional code reader provided with an imaging means capable of imaging the two-dimensional code according to claim 1,
Symbol position detection means for detecting a symbol position of a two-dimensional code imaged by the imaging means;
Data cell position detecting means for detecting the position of the data cell based on the symbol position detected by the symbol position detecting means;
Detecting means for detecting a threshold value assigned to each unit cell of the data cell whose position is detected by the data cell position detecting means; and
A two-dimensional code reading program which functions as a reading means for reading information of a two-dimensional code based on a threshold value of each unit cell detected by the detecting means.

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