JP4488008B2 - Two-dimensional information code - Google Patents

Description

  The present invention relates to a two-dimensional information code having as constituent elements information display unit cells arranged in a matrix and specific patterns serving as position references for specifying the positions of these information display unit cells.

  As this type of two-dimensional information code, there is generally one in which black and white cells are arranged in a matrix to display data values. However, since one cell is expressed by bit information of white or black, reading processing is performed. Can be decoded by a simple binarization process, but the density cannot be increased any more as the amount of information.

  Therefore, it is considered to display information at a high density by colorizing the display of cells as a unit for displaying information. As the method, for example, in addition to black and white in one cell, colors such as red, blue, and green are displayed corresponding to the data value, so that the cell data is represented by two values “0” and “1”. Is increased to five values “0” to “4”. The reading process is performed by determining the color of the cell at the time of reading and making it correspond to the data value.

In the above colorization, it is important to accurately read the color displayed in the cell, and in order to ensure this, conventionally, for example, by implementing a color sample near the matrix. (For example, refer to Patent Document 1). In addition, there is a method for generating a color information code for a barcode (for example, see Patent Document 2).
JP-A-10-283446 JP 2000-67191 A

  The conventional techniques as described above have not been sufficiently technically available in the following points, which has been a problem in practical use. That is, when data is recorded at a high density using many colors, firstly, it is difficult to detect the existence area of the two-dimensional information code, and secondly, an error occurs in determining the color of the information display unit. There are problems such as easy to do.

  Since such problems occur, as a result, there is a technical problem that the time required for reading becomes longer and the amount of error correction increases, and it is necessary to solve these problems. .

  The present invention has been made in view of the above circumstances, and an object of the present invention is to quickly detect the existence area when displaying using colors, and to shorten the time required for reading. Another object of the present invention is to provide a two-dimensional information code that can reduce the amount of error correction.

The invention according to claim 1 is a two-dimensional information code having, as constituent elements, information display unit cells arranged in a matrix and positioning patterns for specifying the positions of the information display unit cells. Five data display colors that can be read by optical means are set corresponding to the data values shown for each cell, and the information display unit cell corresponds to the data value displayed in the cell from among the data display colors The positioning pattern is composed of a peripheral part constituted by the information display unit cell and the remaining part, and the five pieces are arranged in each of the peripheral part and the remaining part. Two data display colors among the data display colors are allocated and configured, and are not used for the positioning pattern among the five data display colors. A four-color reference pattern configured as a block in which a data display color of one color and one data display color of the two data display colors used for the positioning pattern are assigned to each of the four information display unit cells And including three timings of data display colors not used in the positioning pattern, including a timing pattern formed by combining a plurality of the information display unit cells in a row as the plurality of specific patterns. The assigned information display unit cells and the information display unit cells to which one of the two data display colors used for the positioning pattern is assigned are alternately arranged .

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Here, regarding the description of the two-dimensional information code, first, various examples of the two-dimensional information code are shown, and then the reading method will be described.

(1) Outline description of two-dimensional information code (1-1) Example of two-dimensional information code FIG. 1A shows a two-dimensional information code 1 which is an example of a two-dimensional information code according to the present invention. ing. The two-dimensional information code 1 is displayed by a method such as printing on a label or the like in the same manner as a general barcode, and is attached to an article. In the two-dimensional information code 1, for example, various information such as a product serial number, a product name, a unique identification number, a manufacturing date, and a manufacturer are recorded.

  As shown in the figure, the two-dimensional information code 1 is composed of positioning patterns 2a to 2e as specific patterns, a data area 3, and the like. The data area 3 is set so that a data value and a correction code for error correction at the time of reading the data value are displayed in a predetermined area.

  The two-dimensional information code 1 is formed by arranging a large number of square information display unit cells (hereinafter simply referred to as cells) 4 in a matrix, for example, 26 cells vertically and horizontally, and some of the positioning patterns 2a to 2e The remaining area is used as a data area 3.

  Each cell 4 is represented using one of the first to fifth data display colors. As the data display colors, the first to fifth colors “white”, “black”, “red”, “green”, and “blue” are assigned, respectively. The first data display color “white” and the second data display color “black” are selected with the highest contrast. As the third to fifth data display colors, three primary colors of light are selected in consideration of optical reading. These data display color selection settings are not limited to those in the present embodiment, and any color can be used as long as it is a color that can be optically read and identified.

  Now, the positioning patterns 2a to 2e are the first large positioning pattern 2a arranged in the upper left as shown in the figure, and the small size sub-patterns arranged in the lower left, lower right, upper right, and center respectively. The second to fifth positioning patterns 2b to 2e. The first positioning pattern 2a is composed of three parts, an outer frame, a middle frame, and a center part, and the other positioning patterns 2b to 2e are composed of an outer frame and a center part.

  And as for each positioning pattern 2a-2e, as shown in following Table 1, the color of each part is set. In this embodiment, the middle frame or the center is set to “white”, and the outer frame is sequentially set to another color (in the drawing, it is displayed with shading, but the corresponding data display color is It is shown in the figure).

  With the above configuration, all the data display colors used in the cell 4 are indicated by the positioning patterns 2a to 2e. Therefore, when reading, color information is also obtained when the position and range are specified by reading them. Since all data can be obtained, the data in the cell 4 can be read reliably. A specific reading process will be described later.

(1-2) Modification A of two-dimensional information code
Next, FIGS. 1B and 1C show a modification of the two-dimensional information code 1 described above. In this modification, the data display color of the positioning pattern is set to be different. In FIG. 5B, for example, the data display color indicating the second positioning pattern 2b is set to a different color.

  Here, for example, the center of the second positioning pattern 2b is set to “red” as the third color, and the peripheral portion is set to “black” as the second color. In addition, the data display colors used for the other positioning patterns 2a, 2c to 2e can be exchanged and set in a similar manner. In any case, any one of the positioning patterns 2a to 2e may include the first color (white) to the fifth color (green).

  In FIG. 8C, for example, when the color of the background portion K of the portion displaying the two-dimensional information code is dark such as “black”, it is used for the outer frame portion of each positioning pattern 2a to 2e. This is a case of using a two-dimensional information code in which the data display color is set to a light color system such as “white”. In this case, in (1-1), in the middle frame or the central portion of the positioning patterns 2a to 2e, which is a portion using “white” as the first color, the second color “ Display using “black”. That is, the display is made by inverting “white” and “black”. As a result, the contrast with the background color is increased to ensure reading.

(1-3) Modified example B of two-dimensional information code
2D, 2E, and 2F show two-dimensional information codes 5, 6, and 7 in which different specific patterns are set. First, the two-dimensional information code 5 shown in FIG. 6D is a matrix in which 15 cells are arranged in a matrix in each of vertical and horizontal directions. As a specific pattern, a positioning pattern 5a, a four-color reference pattern 5b, a timing pattern 5c, 5d is provided.

  In this two-dimensional information code 5, the positioning pattern 5a located at the upper left is set by “white” and “black” in the same manner as described above, and “black” is excluded from the four-color reference pattern 5b located at the lower right. This is a pattern composed of four cells 4 in which the other four colors (“white”, “red”, “green”, “blue”) are arranged corresponding to each cell 4.

  In addition, the timing patterns 5c and 5d are set in units of a left vertical column and an upper horizontal column, respectively. In these timing patterns 5c and 5d, “white” and other colors are alternately arranged to show all data display colors. For example, in the timing pattern 5c, white, green, white, red, white, blue, white, green, white, and red data display colors are set in the respective cells 4 in order from the left.

  In FIG. 8E, the two-dimensional information code 6 is a matrix in which 31 cells are arranged in a matrix in the vertical and horizontal directions. As a specific pattern, the positioning pattern 6a arranged in the upper left, lower left, lower right, upper Three color reference patterns 6b to 6d arranged respectively, and specific patterns 6g to 6k located at the center of each side and the center of the whole are provided.

  In the color reference patterns 6b to 6d, “red”, “green”, and “blue” are arranged in the outer frame, and “white” is arranged in the center. For the specific patterns 6g to 6k, the outer frame is arranged as “black” and the central portion as “white”.

  In FIG. 8 (f), the two-dimensional information code 7 has 19 cells in the vertical and horizontal directions and is arranged in a matrix, and has an intermediate size between the two-dimensional information codes 5 and 6 described above. is there. In the two-dimensional information code 8 as well, the positioning pattern 7a is arranged in the upper left part and is shown as a color reference pattern in the other corners as described above.

(2) Block Structure of 2D Information Code Next, the block structure of the 2D information code 1 will be briefly described. In the two-dimensional information code 1 used in this embodiment, as shown in FIG. 3B, a block B is configured with four cells 4 as one set. This block size is set on the condition that it can cover the data size when 8 blocks are one block in the conventional method expressed by “white” and “black”. That is, the block B is configured to indicate one data in units of 4 cells.

  That is, in the case of two colors of “white” and “black”, if 8 cells are used, the range of data values that can be taken is 28, which is 256. On the other hand, in the case of this embodiment shown in five colors, 54 is 625 because four cells are used. This data value range corresponds to 9 cells (9 bits = 512 data values) in terms of the expression “white” and “black”. This correspondence is shown in the cell layout diagram of FIG.

  Next, a data expression method will be described. As described above, as the data display colors, the first to fifth colors “white”, “black”, “red”, “green”, and “blue” are assigned, respectively. The following values are associated with each color. That is, the first color “white” for the data value “0”, the third color “red” for the data value “1”, the fifth color “green” for the data value “2”, A fourth color “blue” is set for the data value “3”, and a second color “black” is set for the data value “4”.

  Next, the relationship between the data value of block B and the color will be described. Now, considering the case where the data value is “0”, in the case of FIG. Similarly, in the present embodiment, all of the four cells 4 are set to “white”. However, in this embodiment, in order to avoid that all the blocks B of the data area 3 of the two-dimensional information code 1 become “white”, a certain value is added to the data value to be displayed. The data that has been raised is displayed.

  This is because the range of data values that can be expressed by this block B is “625” with respect to the range of “512” of 9-bit data values shown in FIG. There is room to express. Therefore, even if the data value is “0”, the raised value is set to “86”, that is, “1, 2, 3, 0 ( When data are arranged in order from the bottom digit), the data display colors “red”, “green”, “blue”, and “white” are set.

  As a result, in the expression of the data value “255” of the conventional method as shown in FIG. 4D, the data value of each cell is “1,1,1,1,1,1,1,1,0”. Therefore, 8 cells become “black” and the remaining one cell becomes “white”, whereas the data value “255” is converted as it is, and the data value “0, 1, 0, 2” , And adding “86”, that is, “1, 2, 3, 0”, to the data value “1, 3, 3, 2”, the four cells 4 have “red”, “green”, The data display colors “blue” and “white” are set.

  As a result, a block B that can represent the same amount of data as a block corresponding to 9 cells (9 bits) obtained by adding 1 cell to 8 cells of the conventional method is expressed using 4 cells 4. Furthermore, by shifting (raising) the data value, the displayed color can always include a plurality of data display colors, and the boundaries of the information display unit cells can be easily identified. It becomes easy to process.

(3) Generation process of two-dimensional information code Next, a process in the case of generating the above-described two-dimensional information code 1, 5, 6, 7, etc. will be described with reference to FIG. This will be described with reference to the dimension information code 1). This generation processing is performed by a control device capable of data processing such as a computer.

  First, the control device generates an error correction code for the data value of the two-dimensional information code 1 to be generated by calculation (step S1). Next, the data and the error correction code are divided into blocks B (step S2). For each block B obtained, an error detection code for each block is calculated and added to calculate a block value (step S3). , S4).

  The control device assigns a data display color corresponding to the data value of the obtained block B, arranges it in a two-dimensional area, and generates image data (steps S5 and S6). Subsequently, the control device generates image data using the set data display color corresponding to the positioning block set as the specific pattern (step S7).

  If there is blank data in the data area 3, image data is generated by arranging blocks set in the data display color indicating the raised data “86” corresponding to the data value “0” in the area. (Step S8). Through the above processing, the two-dimensional information code 1 is obtained, and the control device outputs the image data. The output image data can be displayed in various ways in accordance with the case where the two-dimensional information code 1 is displayed by printing, the case where the two-dimensional information code 1 is displayed by an electric means on the display device, or the like.

(4) Reading process of two-dimensional information code (4-1) Configuration of reading device Next, processing when reading the two-dimensional information code 1, 5, 6, 7 and the like configured as described above by the reading device 10 explain. FIG. 4 shows the electrical configuration of the two-dimensional information code reader 10.

  The reading device 10 includes, for example, a hand-held type and a stationary type, and each includes an optical reading unit and a data processing unit. As an optical reading unit, LEDs 11 and 12 that project white light from a plurality of directions onto a recording surface D such as a sheet on which the two-dimensional information code 1 to be read is recorded and images of the recording surface D are displayed. A lens 13 for photographing and a CCD (Charge Coupled Device) image sensor 14 are provided.

  The entire internal control is performed by the control unit 15. The control unit 15 is provided with an internal memory, an interface, and the like mainly using a CPU, and stores a reading processing program. The above-described output terminal of the CCD image sensor 14 is connected to the memory 18 via the amplifier circuit 16 and the A / D conversion circuit 17. In addition, the output terminal of the A / D conversion circuit 17 is connected to the memory 18 via the specific ratio detection circuit 19.

  An image signal photographed by the CCD image pickup device 14 is amplified in an analog manner by an amplifier circuit 16, converted into a digital signal through an A / D conversion circuit 17, and stored in a memory 18 as binarized image data. The In this embodiment, the captured image of the two-dimensional information code 1 captured by the CCD image sensor 14 is captured as a color image, converted into a digital signal, and then light / dark image data, R (red) image data, G Each of (green) image data and B (blue) image data is stored in the memory 18.

  The CCD image pickup device 14 and the specific ratio detection circuit 19 are supplied with a synchronization signal from a synchronization signal generation circuit 20. The synchronization signal generation circuit 20 provides a synchronization signal also to the address generation circuit 21, and provides an address signal to the memory 18. The LEDs 11 and 12, the amplifier circuit 16, the A / D conversion circuit 17, the specific ratio detection circuit 19 memory 18, and the synchronization signal generation circuit 20 are configured to receive a control signal from the control unit 15 and to exchange information. Yes.

  The reading device 10 is provided with an operation switch 22 for performing various operation inputs, and the control unit 15 receives inputs. Further, the control unit 15 is provided with an LED 23, a buzzer 24, a liquid crystal display 25, and the like for displaying a control state and performing a notification operation. Furthermore, a communication interface 26 for communicating with an external device is connected.

(4-2) Explanation of Reading Processing FIG. 6 shows the processing contents of the reading processing program, and the control unit 15 gives a control signal to each unit to execute the reading processing. First, the light emitting LEDs 11 and 12 are turned on, and an image of the recording surface D is taken by the CCD image pickup device 14. At this time, white light is projected from the LEDs 11 and 12, and the two-dimensional information code 1 displayed in the color recorded on the recording surface D is photographed (step P1).

  The image signal from the CCD image pickup device 14 is divided into three RGB signals, and at this time, light / dark image data is obtained from these signals by calculation and stored in the memory 18 together with the RGB image data (step). P2). Next, the control unit 15 performs a decoding process on the two-dimensional information code 1 based on the read image data. First, the specific patterns, that is, the positioning patterns 2a to 2e are searched from the light / dark image data (step P3).

  When detecting the position of the specific pattern, the control unit 15 specifies the existence area of the two-dimensional information code 1 based on the position (step P4). Next, each color reference value assigned to the positioning patterns 2a to 2e of the specific pattern is acquired, and a threshold for determining each data display color is set (step P5). This principle will be described later.

  Thereafter, the control unit 15 determines and specifies the data display color of each cell in the data area 3 based on the threshold value obtained as described above (step P6). Next, each cell 4 in the data area 3 is divided into the set block B (step P7), and the data value set in each block is obtained (step P8). At this time, the presence / absence of an error is also checked, and if an error exists, an error correction process is performed using a correction code (step P9). When the above processing is repeated and data values are obtained for all blocks, the data is output (step P10).

  In the above case, the threshold value setting process performed in step 5 of the control unit 15 can be obtained by a logical calculation as follows. FIG. 7 shows the principle. That is, when the image data is converted from an analog signal to a digital signal, it is necessary to discriminate each of the RGB signals. For example, in the R image signal level, the “red” signal level and the “white” signal level are determined. There is no big difference in level, and it becomes a level similar to “bright”. On the other hand, in the signal level of the R image, the signal levels of “black”, “green”, and “blue” are not significantly different, and are similar to “dark”.

  As for this tendency, in the signal level of the G image, “green” and “white” are “bright” levels, and “black”, “red”, and “blue” are “dark” levels. Similarly, in the signal level of the B image, “blue” and “white” are “bright” levels, and “black”, “red”, and “green” are “dark” levels. Therefore, in all the determinations, “white” when the signal level is “light”, “black” when the signal level is “dark”, and only when the image data has its own data display color “ When “bright” is “dark” in other image data, it can be determined as the data display color. By setting the threshold value as described above, the data display color for each cell can be reliably determined based on each image data.

  Since each data display color is arranged at a predetermined position in the specific pattern, when setting a threshold for determining the data display color, the threshold is set with reference to this. For example, an intermediate level between red and white brightness levels and blue, green, and black brightness levels is set. By performing this for each data display color, it is possible to set a threshold value that can be reliably determined.

(5) Description of split display of two-dimensional information code FIG. 8 shows a display example when split display of the two-dimensional information codes 1, 5, 6, 7 and the like. This is a display method that is effective when, for example, the size of the two-dimensional information code 1 is large and the display area for displaying the code is limited. In other words, when the area for displaying pre-generated or generated data is narrow and all cells cannot be displayed at once, the two-dimensional information code that is configured to be large is divided and displayed sequentially. It is a thing.

  A method of the division display will be briefly described. The size of the number of displayable cells is set with respect to the size corresponding to the original number of cells of the two-dimensional information code to be displayed. At this time, the number of divisions (for example, 4) is determined from the corresponding number of cells.

  Next, the data value of the original two-dimensional information code is divided into the number of divisions described above and given an order according to the order (A, B, C, D). Each divided data value is converted into a corresponding partial two-dimensional information code having the number of cells set as described above (see FIG. 5B). Thereby, a set of partial two-dimensional information codes is generated. When the display is performed, the display is switched and displayed at a predetermined timing in the order of order (see (a) in the figure).

  During the reading process, the sequentially fetched two-dimensional information code is decoded, and when it is recognized that there is an order, when a predetermined number is fetched, it is fetched as a set of two-dimensional information code data. Thereby, even in a compact display area, it is possible to display a two-dimensional information code corresponding to a large size. In this embodiment, as described above, since the two-dimensional information code is set to be displayed in color, a more compact display can be performed, in other words, an efficient display with a large amount of information can be performed. Will be able to.

The present invention is not limited to the above embodiment, and can be modified or expanded as follows.
Although only the error detection code is added to the data block B, an error correction code having an error correction function may be included. As a result, the function of correcting the error location can be achieved by the individual block, so that it can be recognized quickly and accurately.

  In addition to the five colors described above, various data display colors can be used as long as they can be read optically. The data display color is not limited to five colors, and a data display color within a possible range of three or more colors can be used. Can be used.

Display example of two-dimensional information code showing one embodiment of the present invention Display example of two-dimensional information code shown in different patterns Diagram for explaining data block Two-dimensional information code generation processing program Electrical configuration diagram of two-dimensional information code reader Two-dimensional information code reading processing program Illustration of level judgment of image signal Illustration of split display of 2D information code

Explanation of symbols

  1, 5, 6 and 7 are two-dimensional information codes, 2a to 2e are positioning patterns (specific patterns), 3 is a data area, 4 is an information display unit cell, 5c and 5d are timing patterns, 10 is a reader, Reference numeral 12 denotes an LED, 14 denotes a CCD image pickup device, 15 denotes a control unit, 18 denotes a memory, and 19 denotes a specific ratio detection circuit.

Claims (4)

In the two-dimensional information code having as constituent elements information display unit cells arranged in a matrix and a plurality of specific patterns serving as position references for specifying the positions of the information display unit cells.
Five data display colors readable by optical means are set corresponding to the data values shown for each information display unit cell,
The information display unit cell is provided so that a data display color corresponding to a data value displayed in the cell is displayed from the data display colors.
As the plurality of specific patterns, a positioning pattern for specifying the position of the information display unit cell and a block obtained by combining four pieces of the information display unit cell, four colors among the five data display colors are selected. A four-color reference pattern configured to be assigned to each information display unit cell;
The positioning pattern is composed of a peripheral portion constituted by the information display unit cell and the remaining portion, and two data display colors of the five data display colors in each of the peripheral portion and the remaining portion. Assign and configure
Four data including three data display colors that are not used in the positioning pattern among the five data display colors for each of the four information display unit cells. Assign and configure display colors ,
The information display unit to which each of the three data display colors not used in the positioning pattern is assigned, including a timing pattern formed by combining a plurality of the information display unit cells in a row as the plurality of specific patterns. A two-dimensional information code , wherein cells and the information display unit cells to which one data display color of two data display colors used for the positioning pattern is assigned are alternately arranged . The two-dimensional information code according to claim 1,
From the five data display colors to the four information display unit cells, the information display unit cells included in the data block have a data display color different from “white” corresponding to the color of the background portion. A value obtained by allocating four different data display colors and not exceeding the difference between the range of data that can be expressed by a 4-digit value converted into a 5-value and the maximum value of the 9-bit data to be displayed. set the value as a raising value, the for the respective data blocks, the two-dimensional information code, characterized in that it is set as shifted by adding the raised value the setting. The two-dimensional information code according to claim 1 or 2,
The two-dimensional information code , wherein the positioning pattern is set so as to assign first and second data display colors having a large optical contrast to each of the peripheral portion and the remaining portion . In the two-dimensional information code according to claim 3 ,
The two-dimensional information code, wherein the first and second data display colors are set to black and white .

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