JP4567151B2 - 2D code creation method and paper with 2D code - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a so-called two-dimensional code creation method in which data displayed in a binary code is arranged as a two-dimensional matrix and a sheet having a two-dimensional code.
[0002]
[Prior art]
Conventionally, a two-dimensional code 100 as shown in FIG. 6 is known. The two-dimensional code 100 is printed and displayed on various types of securities in the form of cards (for example, gift certificates and admission tickets) and forms P. The sheet P is supplied to a reader and read. To recognize the information given to the code. Compared with a bar code that displays information linearly in one dimension, it has a broader plane and can be given more information, so the two-dimensional code 100 will be used in the future. .
[0003]
In the two-dimensional code 100, either one of white indicating “0” and black indicating “1” is printed in each section (cell Sij) divided into the row Ni and the column Mj. It is formed by. Incidentally, since it is common to apply the background color of the paper for white, only the black indicating “1” is actually printed to form the two-dimensional code 100.
[0004]
Such a reading device for reading a two-dimensional code has a feeding means for feeding the paper P into the apparatus, and a sheet Ni moving in the direction perpendicular to the traveling direction with respect to the paper moving by the driving of the feeding means. Scanning means for reading the value of the cell Sij. Accordingly, by passing the paper P through the reading device, the scanning means sequentially reads the value (“0” or “1”) of each column Mj for each row Ni, and the paper P passes through the scanning means, and each cell. All the values of Sij (“0” or “1”) are read.
[0005]
By the way, the time interval of scanning by the scanning means (the time interval of scanning between the row Ni and the row Ni + 1) is set in advance, so that the time interval is synchronized with the feeding speed of the feeding means. (For example, the paper P is fed by one line for each scanning of one line), and the value of each column Mj in each line Ni is accurately determined in such a way that each line Ni is separated so as not to cause confusion between adjacent lines. Although the feeding speed by the feeding means is not necessarily constant due to load fluctuations, voltage fluctuations, and the like, the data of the row Ni read by the scanning means is not necessarily the data of that line. Not confirmed.
[0006]
Therefore, conventionally, in order not to cause such inconvenience, a total of two columns of positioning codes 101 over one column are provided on both sides in the width direction of the two-dimensional code 100, and each row of the positioning code 101 is provided in each row. The positioning cell CSi is set so as to correspond to Ni. Then, black (“1”) and white (“0”) are alternately printed on each positioning cell CSi, and the scanning means reads this positioning cell CSi, and the change of this value is the next row Ni. It is made to be recognized. By doing so, even if the feeding speed of the paper P fluctuates, there is no inconvenience that the data for each line is confused.
[0007]
[Problems to be solved by the invention]
However, in the conventional system in which the positioning cells CSi are provided on both sides of the two-dimensional code 100, the presence of the positioning cells CSi is present when the overall area for the two-dimensional code 100 on the paper P is limited. As a result, the capacity of the two-dimensional code 100 is reduced correspondingly, but if the capacity of the two-dimensional code 100 is to be secured, the entire area of the sheet P has to be increased.
[0008]
In addition to reading the two-dimensional code 100, the reading device must always check whether or not a line change has been made by reading the positioning code 101, and this process prolongs the access time. There is also a problem that it is difficult to read the code 100 at high speed.
[0009]
Furthermore, since the conventional two-dimensional code 100 simply converts the original data into a binary number and converts “0” to white and “1” to black, each color is changed to “0” and “1”. Since the original data can be obtained in binary numbers simply by returning it, the contents of the data can be decrypted very easily.
[0010]
The present invention has been made to solve the above problems, and can correctly read the value of each cell of a two-dimensional code without providing a positioning code adjacent to the two-dimensional code. An object of the present invention is to provide a method for creating a two-dimensional code and a sheet provided with the two-dimensional code, in which security measures are taken.
[0011]
[Means for Solving the Problems]
  The invention described in claim 1 is a method of creating a two-dimensional code in which either one of two different colors is given to each element of a matrix of n rows and m columns, and a plurality of binary data of the original data For each element of the binary number original data matrix | Bij | (i = 1 to n, j = 1 to m−1), a predetermined procedure is performed so as to correspond to the first to m−1th columns of the elements for each row. The obtained modulation elements are sequentially assigned from the second column excluding the first column of the modulation elements, and the first column of the modulation elements is set as a predetermined element, so that the binary elements corresponding to the two-dimensional code are set. A modulation code matrix | Aij | (i = 1 to n, j = 1 to m) is created, and coloring corresponding to each element of the modulation code matrix | Aij | Is to createAs the predetermined procedure, each row of the binary original data matrix | Bij | for each of the case where the modulation element in the first column of each row of the modulation code matrix | Aij | is “0” and “1”. For each binary element data matrix | Bij | corresponding to the modulation element, it is determined whether the element of the corresponding column is “0” or “1”. If the element of the corresponding column is “0”, the modulation is performed. While the element is the modulation element of the next column, and the element of the corresponding column is “1”, the modulation process of changing the modulation element of the next column to a modulation element different from the modulation element is performed, and the modulation of the first column One of the modulation processes when the element is set to “0” and “1” is selected, and the selection of the modulation process for each of the second and subsequent lines includes the current line and the previous line. The sum of the absolute values of the differences in the modulation elements between the columns is larger. To select the tone processingA method of creating a two-dimensional code characterized by the above. It is.
[0012]
  The invention according to claim 3 is a sheet provided with a two-dimensional code in which either one of two different colors is given to each element of a matrix of n rows and m columns, and a plurality of binary data of the original data A predetermined procedure for each element of the binary original data matrix | Bij | (i = 1 to n, j = 1 to m−1) so as to correspond to the first to m−1th columns of the elements for each row. Are sequentially assigned from the second column excluding the first column of the modulation elements, and the first column of the modulation elements is set as a predetermined element, thereby providing a binary element corresponding to the two-dimensional code. A modulation code matrix | Aij | (i = 1 to n, j = 1 to m) is created and colored corresponding to each element of the modulation code matrix | Aij |The predetermined procedure is as follows. For each of the cases where the modulation element in the first column of each row of the modulation code matrix | Aij | is “0” and “1”, each row of the binary original data matrix | Bij | For each binary element data matrix | Bij | corresponding to the modulation element, it is determined whether the element of the corresponding column is “0” or “1”. If the element of the corresponding column is “0”, the modulation While the element is the modulation element of the next column, and the element of the corresponding column is “1”, the modulation process of changing the modulation element of the next column to a modulation element different from the modulation element is performed, and the modulation of the first column One of the modulation processes when the element is set to “0” and “1” is selected, and the selection of the modulation process for each of the second and subsequent lines includes the current line and the previous line. Modulation with the larger absolute value of the difference in modulation elements between each column One in which you select the physicalA sheet having a two-dimensional code characterized by the above.
[0013]
According to these inventions, the modulation code matrix | Aij | (i = 1 to n, j = 1 to m) formed by a predetermined procedure is represented by a binary original data matrix | Bij | (i = 1 to n, There is an increase in code digits for one column compared to j = 1 to m−1), but the number of columns may be reduced by one column compared to a conventional code matrix in which positioning codes are added to both ends of each row. Therefore, when the entire area of the area for the two-dimensional code is limited, the information amount of the modulation code matrix | Aij | can be made larger than that of the conventional one, while the predetermined information amount is secured. In this case, the area of the modulation code matrix | Aij | in the entire sheet can be reduced.
[0014]
Further, by appropriately setting a predetermined procedure, each row of the modulation code matrix | Aij | can be distinguished from each other without providing a positioning code, which is separate from reading a two-dimensional code. 2D code can be read at a higher speed than before because the conventional inconvenience of having to always check whether the line change has been performed by reading the positioning code is solved and the access time is shortened. become.
[0015]
Furthermore, the modulation code matrix | Aij | is not obtained by simply converting the original data into binary numbers, but instead converting the elements of the binary original data matrix | Bij | The original data cannot be reproduced simply by fitting “0” to “0” and black to “1”, which is effective in maintaining the confidentiality of the data and solves the security problem.
[0018]
  In the predetermined procedure,Binary data matrix | Bij |Against aboveModulation code matrix | Aij |Is obtained. This modulation code matrix | Aij |In this case, the adjacent elements in each row are compared with each other and set to “0” when they are the same, and set to “1” when they are the same, and the matrix obtained by sequentially performing such processing is the original matrix The binary number original data matrix | Bij |
[0019]
  Further, the above modulation processing is performed for each of the case where the modulation element in the first column of each row of the modulation code matrix | Aij | is “0” and “1”, and the modulation element in the first column is One of the modulation processes in the case of “0” and “1” is selected, and the selection of the modulation process for each of the second and subsequent lines is as follows. Modulation process in which the sum of absolute values of differences in modulation elements between columns is largerIs selected, a modulation code matrix | Aij | that can significantly express a difference between rows as a two-dimensional code is formed. Accordingly, by sequentially reading each row of the modulation code matrix | Aij | without providing a positioning code as in the prior art, the distinction between columns can be easily recognized based on the above bias.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a diagram showing an embodiment of a two-dimensional code according to the present invention. (A) is a state where elements of a code matrix are color-coded into white and black, and (b) is white indicating “0”. , Black is replaced with “1” and converted into a binary code matrix.
[0021]
As shown in FIG. 1A, the two-dimensional code 100 is a variety of information (for example, date, reference number, sales location, etc.) that has been modulated into a predetermined area of paper P such as a gift certificate or admission ticket. (Amount of money, expiration date, etc.) are printed, and are formed by dividing a plurality of square-shaped squares by vertical and horizontal lines so that they can be obtained vertically and horizontally. In the example shown in FIG. 1A, the two-dimensional code 100 is formed over substantially the entire area of the paper P for convenience of illustration. However, in the present invention, the two-dimensional code 100 is the entire area of the paper P. The sheet P is not limited to be formed, and can be set at an arbitrary position such as a corner or a center in accordance with a print layout corresponding to the purpose of use of the paper P.
[0022]
The two-dimensional code 100 is formed by including a matrix of n rows by a plurality of cells (cells) and m columns Mj, i rows and j columns (where i = 1 to n, j = 1 to m), that is, white or black is printed on the cell Sij, and various types of information are displayed in combination. For white, the background color of the paper P is generally adopted as it is, and therefore, actually, only the black color is printed in a predetermined cell Sij, and the two-dimensional code 100 is completed. Incidentally, in FIG. 1, the two-dimensional code 100 is shown in the form of 4 rows and 6 columns (n = 4, m = 6) for convenience of illustration, but in the present invention, the 2D code 100 is 4 rows and 6 columns. It is not limited to being.
[0023]
In such a two-dimensional code 100, the white cell Sij is determined to be “0” and the black cell Sij is determined to be “1”. Accordingly, as shown in FIG. 1B, the two-dimensional code 100 corresponds to a modulation code matrix | Aij | in which binary numbers are described for each row.
[0024]
Incidentally, in the example shown in FIG. 1, the first row and the first column of the two-dimensional code 100 are white as shown in (a), and accordingly the modulation code matrix | Aij | As shown in (b) of FIG. 1, “0” is set in the first row and the first column, and similarly, modulation corresponding to the black color in the first row and the second column of the two-dimensional code 100 is performed. “1” is set in the first row and the second column of the code matrix | Aij |. The first row of the modulation code matrix | Aij | is “011000”, the second row is “000111”, the third row is “110001”, and the fourth row is “100111”. The numerical information of the decimal number is set respectively.
[0025]
Such a two-dimensional code 100 (that is, modulation code matrix | Aij |) is further added to original data (binary number original data matrix | Bij |) obtained by binarizing raw data such as date and reference number. It is formed by performing the modulation process. Hereinafter, this modulation processing will be described with reference to FIG.
[0026]
FIG. 2 is a diagram showing a binary original data matrix | Bij | corresponding to the modulation code matrix | Aij | of FIG. As shown in this figure, the binary original data matrix | Bij | (i = 1 to n (n = 4), j = 1 to m-1 (m-1 = 5)) is 4 rows and 5 columns. The modulated code matrix | Aij | after the modulation is 4 rows and 6 columns, but one row less. In other words, by modulating the binary original data matrix | Bij |, the number of rows is increased by 1 to become the modulation code matrix | Aij |. That is, in the binary original data matrix | Bij |, the value of each column M'j for each row N'i is changed to the value of each column Mj for each row Ni of the modulation code matrix | Aij | by a predetermined modulation process. Thus, a modulation code matrix | Aij | is formed. In the specific examples of FIGS. 1 and 2, “10100”, “00100”, “01001” and “10100” in the first to fourth rows of the binary original data matrix | Bij | It is modulated to “011000”, “000111”, “110001”, and “100111” of the modulation code matrix | Aij | ((b) in FIG. 1).
[0027]
FIG. 3 is an explanatory diagram for explaining the modulation processing. Referring to this figure, first, when the first row N′1 (“10100”) of the binary original data matrix | Bij | is modulated to the first row N1 (“011000”) of the modulation code matrix | Aij | Will be described in detail, and the modulation after the second row N′2 will be described.
[0028]
As shown in FIG. 3, when performing modulation, a modulation process {circle over (1)} that performs modulation processing by setting “0” in the first column M1 of the first row N1 of the modulation code matrix | Aij | A modulation process {circle over (2)} is performed in which “1” is set and the modulation process is performed.
[0029]
In each modulation process, the modulation element in the first column of each row of the modulation code matrix | Aij | is “0” (modulation process (1)) and “1” (modulation process (2)). The value of the modulation element Aij is set for each of ▼) according to the value of the element Bij of the binary original data matrix | Bij | in the same column, and the modulation element Aij in the next column is sequentially determined. When the element Bij of the binary number original data matrix | Bij | of the corresponding column of the modulation element Aij is “0”, the modulation element Aij of that column is set as the modulation element Ai (j + 1) of the next column. That is, each element Bij of the binary number original data matrix | Bij | plays a role as a control signal (command) when setting the modulation element Aij of the modulation code matrix | Aij |.
[0030]
In the specific example of FIG. 3, in the case of the modulation process {circle around (1)}, the first row and the first column (element B11) of the binary original data matrix | Bij | are “0”, so the modulation code matrix | Aij | “0” in the first row and first column (modulation element A11) is set in the first row and second column (modulation element A12) of the modulation code matrix | Aij |, and modulation is performed by sequentially repeating the same processing. The first row N1 of the code matrix | Aij | is “011000”. Similarly, in the case of the modulation process (2), the first row N1 of the modulation code matrix | Aij | is “100111”.
[0031]
In determining the first row N1 of the modulation code matrix | Aij |, it is arbitrary which of the modulation results (1) and (2) is used. In the present embodiment, the result of the modulation process (1) is adopted.
[0032]
Next, in obtaining the second row N2 of the modulation code matrix | Aij |, the same modulation processing (1) and modulation processing (2) are executed, and “000111” is obtained as a result of the modulation processing (1). However, “111000” is obtained as a result of the modulation process (2). For the second and lower rows N2 and below of the modulation code matrix | Aij |, the difference between each column in this row and each column in the row immediately above is calculated one by one, and the modulation processing with the larger sum of their absolute values is performed. The result is selected. In the example shown in FIG. 3, when modulation processes {circle around (1)} and {circle around (2)} that are candidates for the first row N1 and the second row N2 of the modulation code matrix | Aij |
1st line "011000"
Modulation process (1) “000111”
Modulation process (2) “111000”
It becomes.
[0033]
Then, the difference between each column of the modulation process {circle around (1)} and each column of the first row N1 of the modulation code matrix | Aij | Similarly, the difference between each column of the modulation process {circle around (2)} and each column of the first row N1 of the modulation code matrix | Aij | is calculated one by one and the absolute value thereof is summed to be “1”. Therefore, the result of the modulation process (1) having a large absolute value is selected as the second row N2 of the modulation code matrix | Aij |.
[0034]
Such a modulation process is similarly executed for the third and lower rows N3 of the modulation code matrix | Aij |, and as a result, a modulation code matrix | Aij | as shown in FIG. . The modulation code matrix | Aij | obtained by such processing has a very high probability that the same column between adjacent rows has a different value. As shown in FIG. 1 (a), the black and white are very clearly divided between the lines, and the boundary between the lines is very easy to see, and also when the two-dimensional code 100 is read by the reader, the apparatus In this way, it is possible to reliably perform the line segmentation process.
[0035]
Hereinafter, reading of the two-dimensional code 100 will be described with reference to FIGS. 4 and 5. FIG. 4 is a schematic perspective view of a reading device for explaining a reading device that reads the two-dimensional code 100, and FIG. 5 is an explanatory diagram for explaining reading scanning by CIS. First, as shown in FIG. 4, the reading device 1 includes a pair of upper and lower feed rollers 2 that feed the paper P into the device at a predetermined feed speed, and a two-dimensional paper P that is being fed by the feed roller 2. A CIS (contact image sensor (contact image line sensor)) 3 that reads the code 100 and a control device 4 that performs a predetermined process on the value of each cell Sij read by the CIS 3 and classifies the value for each row Ni. It is configured.
[0036]
The CIS 3 has a plurality of contact sensors 3j (i = 1 to m (m = 6 in the present embodiment, the actual number of contact sensors 3j) provided on the surface facing the paper P corresponding to each row Mj. Has a modulation code matrix | Aij |, which is considerably larger than six, and is set to six according to the scale of the modulation code matrix | Aij |) described above, and the reflection of the two-dimensional code 100 from the paper surface to these contact sensors 3j. Each contact sensor 3j converts the incident light into a current value proportional to the amount of incident light and outputs it to the control device 4. The reading of the two-dimensional code 100 by the CIS 3 is intermittently performed every preset several μsec, and the sheet P moves at a predetermined speed, so that the cells Sij in each row Ni of the two-dimensional code 100 are targeted. Several data points per line It should be noted that the number of data collection points by the contact sensor 3j per line of the two-dimensional code 100 varies depending on the movement speed of the paper P, and therefore is not necessarily constant. Absent.
[0037]
The control device 4 determines the delimiter of each row of the modulation code matrix | Aij | from each set of data (line data) read by the contact sensor 3j of the CIS 3, and determines the value of each modulation element Aij. It functions to restore each modulation element Aij value to the element Bij of the binary original data matrix | Bij |. The data conversion unit 41, the line data comparison unit 42, the row data setting unit 43, and the original data A restoration unit 44 and a suitability determination unit 45 are provided. The determination result by the suitability determination unit 45 is output to the output device 46 and expires when a predetermined action based on the determination result (for example, the modulation code matrix | Aij | is given to the admission ticket) by the function of the output device 46 If it is determined that the entrance gate is not suitable, an action such as closing the entrance gate) is performed.
[0038]
The data converter 41 converts a current value, which is an analog amount based on the intensity of reflected light read from the two-dimensional code 100 by the contact sensor 3j of the CIS 3, into a digital value of “0” or “1”. . A preset current threshold value is input into the data conversion unit 41 that converts the two-dimensional code 100 into data, and the current value from the contact sensor 3j is compared with this threshold value. As this threshold value, an intermediate current value between the current value from the contact sensor 3j when the cell Sij is white and the current value from the contact sensor 3j when the cell Sij is black is employed. When the current value is larger than the threshold value, it is determined as “0” (white), while when the current value is smaller than the threshold value, it is determined as “1” (black).
[0039]
The data conversion unit 41 also has a function of converting the current value from the CIS 3 into a numerical value as it is and storing it. The numerically converted value is used when the next line data comparison unit 42 determines the row section of the two-dimensional code 100.
[0040]
The line data comparison unit 42 compares the previous value with the current value for the current value of each column of the two-dimensional code 100 read by the contact sensor 3j of the CIS 3 one by one. It finds out whether it is changing or not and determines the partition of the row. The current value is “0” when the cell Sij of the paper P is a complete black body, “10” when the cell Sij is completely white, and is 0 or more and 10 or less depending on the brightness of the reflected light. A value is given.
[0041]
In the following, a method for determining a row segment will be described based on the example shown in FIG. In FIG. 5, scanning by CIS3 is expressed by a one-dot chain line, and the detected current value of the cell Sij is written in each cell Sij. That is, the brightness (that is, the current value) of each cell Sij of the two-dimensional code 100 is detected by the CIS 3 that is stationary by actually moving the sheet P upward in FIG. In FIG. 5, for convenience of explanation, the CIS 3 moves with respect to the stationary paper P.
[0042]
As shown in FIG. 5, in the first scan, the contact sensors 31, 32... 3j... 36 read the reflected light of the cells S11, S12. Output to the conversion unit 41. The data converter 41 converts this current value into a numerical value of 0 to 10 according to the magnitude. In the example of FIG. 5, since the cells S11 to S16 of the two-dimensional code 100 are “white, black, black, white, white, white”, the current value is “8, 0, 0, 8, 8, 8”. It becomes. The reason why white is set to “8” is that the ground color of the paper P is not necessarily completely white.
[0043]
Next, after a predetermined interval time has elapsed, the second operation is performed, and S1j (j = 1 to 6) is read at this time, and the detected current value is “8, 0, 0, 8, 8, 8 ". Then, immediately after the second detection is performed, the difference between the current values for each column is calculated, and then the absolute value of each difference is calculated according to the following calculation formula.
[0044]
X = Σ | X_kj-X_{(k-1) j}｜
(K = 1-12, j = 1-6)
X: Total difference between current and previous current values for each column
k: Number of scans
j: Number of columns of the two-dimensional code 100
X_kj: Current value of cells in column j in this scan
X_{(k-1) j}: Current value of cells in column j in the previous scan
In the example shown in FIG. 5, for k = 1 and k = 2,
X = | 8-8 | + | 0-0 | + | 0-0 | + | 8-8 | + | 8-8 | + | 8-8 | = 0
Therefore, it is determined that the first scan and the second scan are in the same column in the cell Sij of the two-dimensional code 100. Whether or not they are the same column based on the value of X is determined by using 1/2 as the threshold value when X and all columns are reversed in black and white in the current scan and the previous scan. When it is equal to or larger than this threshold, it is determined that the column has changed. In the example of FIG. 5, the threshold value is “24” ((8 × 6) / 2) where “8” is white and “0” is black.
[0045]
Since the value of X obtained for the second scan and the third scan is also “0”, it can be seen that the third scan is for the first row.
[0046]
Next, the result of the third scan is compared with the result of the fourth scan. In this case, the third scan is for the first row (i = 1) of the cell Sij as in the second scan, while the fourth scan is for the second row ( Since i = 2), the current detection result by the contact sensor 3j is “888000”. When X is calculated by comparing the result of the fourth scan with the result of the third scan,
X = | 8-8 | + | 8-0 | + | 8-0 | + | 0-8 | + | 0-8 | + | 0-8 | = 40
Thus, when the threshold value is greater than “24”, it is determined that the fourth scan is for the second row of the cells Sij. Thereby, it is determined that the detection results by the CIS3 from the first to the third time are those of the first row of the cell Sij. The same scanning by CIS3 is continued thereafter, and the values of all the cells Sij are determined by repeating 12 times in total.
[0047]
Note that the square sum Y of the difference between columns instead of the above X, that is,
Y = Σ (X_kj-X_{(k-1) j})²
(K = 1-12, j = 1-6)
May be adopted.
[0048]
The row data setting unit 43 functions to set the value of the modulation element Aij of each column in the previous row when it is determined that the row of the cell Sij has changed as a result of the comparison by the line data comparison unit 42. To do. That is, in the example of FIG. 5, it is determined that the row of the cell Sij has changed from the first row to the second row based on the third scan result and the fourth scan result. The average value of the detection results from the first time to the third time is calculated, and this average value becomes the data of the first row. In particular,
Cell S_1j(J = 1-6) = “011000”
Cell S_2j(J = 1-6) = “000111”
Cell S_3j(J = 1-6) = “110001”
Cell S_4j(J = 1-6) = “100111”
It becomes. This modulation code matrix | Aij | is a value that is read by the CIS 3 from the two-dimensional code 100 and converted by the line data comparison unit 42, and this matrix is stored in the row data setting unit 43.
[0049]
The original data restoration unit 44 plays a role of restoring the modulation code matrix | Aij | stored in the row data setting unit 43 into a binary original data matrix | Bij |. Here, in the modulation code matrix | Aij |, adjacent ones of the modulation elements Aij in the same row are sequentially compared. If they are the same, “0” is set, and if they are different, “1” is set and the matrix is set. Made. This matrix becomes the binary original data matrix | Bij |.
[0050]
For example, modulation element A_1jIn the case of (j = 1 to 6), the cell S_1jSince the value is “011000” and the first column and the second column are compared, the value is different between “0” and “1”.₁₁= 1. When the second column and the third column are compared, the value is the same for “1” and “1”, so element B₁₂= 0. Similarly, by obtaining the element Bij in the same manner,
Element B_1j(J = 1 to 5) = “10100”.
[0051]
The suitability determination unit 45 is configured to compare the binary original data matrix | Bij | restored by the original data restoration unit 44 with a preset value of suitability to determine suitability. The determination result is output to the output device 46, and a predetermined process is performed.
[0052]
【The invention's effect】
According to the first and third aspects of the invention, the modulation code matrix | Aij | (i = 1 to n, j = 1 to m) formed by a predetermined procedure is represented by a binary original data matrix | Bij | (i = 1 to n, j = 1 to m-1), the code digit is increased by one column, but the number of columns is reduced by one column compared to a conventional code matrix in which positioning codes are added to both ends of each row. Therefore, when the total area area for the two-dimensional code is limited, the information amount of the modulation code matrix | Aij | can be made larger than the conventional one, while a predetermined amount of information is secured. In order to achieve this, the area of the modulation code matrix | Aij |
[0053]
Further, by appropriately setting a predetermined procedure, each row of the modulation code matrix | Aij | can be distinguished from each other without providing a positioning code, which is separate from reading a two-dimensional code. The conventional inconvenience of having to constantly check whether or not the line change has been performed by reading the positioning code is solved, the access time is shortened, and the two-dimensional code can be read at a higher speed than before. .
[0054]
Further, the modulation code matrix | Aij | is not obtained by simply binary conversion of the original data, but is obtained by converting the elements of the binary original data matrix | Bij | The original data cannot be reproduced simply by fitting “0” to “0” and black to “1”, which is effective in maintaining confidentiality of data, and can further improve security.
[0055]
According to the second and fourth aspects of the invention, the binary original data matrix for each of the case where the modulation element in the first column of each row of the modulation code matrix | Aij | is “0” and “1”. For each row of | Bij |, the modulation element is compared with the element of the corresponding column of the binary original data matrix | Bij |. When the element of the corresponding column is “0”, the modulation element is compared with the modulation element of the next column. In addition, the modulation element in the first column in each row of the modulation code matrix | Aij | is selected so that the sum of the absolute values of the differences between the columns in the adjacent row of the obtained modulation code matrix | Aij | Since the modulation code matrix | Aij | is obtained, the modulation code matrix | Aij | obtained in this way is selected when the first row is “0” or “1”. Sum of absolute values of differences between columns in adjacent rows By selects whichever larger, 2-dimensional code as the line spacing significantly expressed to be modulated code matrix of | Aij | can be formed. Accordingly, by sequentially reading each row of the modulation code matrix | Aij | without providing a positioning code as in the prior art, it is possible to easily recognize the column distinction based on the above-described bias.
[Brief description of the drawings]
1A and 1B are diagrams showing an embodiment of a two-dimensional code according to the present invention, in which FIG. 1A is a state in which elements of a code matrix are color-coded into white and black, and FIG. , Black is replaced with “1” and converted into a binary code matrix.
FIG. 2 is a diagram illustrating a binary original data matrix | Bij | that is a basis of the modulation code matrix | Aij | of FIG. 1;
FIG. 3 is an explanatory diagram for explaining a modulation process;
FIG. 4 is a schematic perspective view of a reading device for explaining a reading device that reads a two-dimensional code.
FIG. 5 is an explanatory diagram for explaining reading scanning by CIS.
FIG. 6 is an explanatory diagram showing an example of a conventional two-dimensional code.
[Explanation of symbols]
1 Reader
2 Feed roller
3 CIS
4 Control device
41 Data converter
42 Line data comparator
43 Line data setting part
44 Original data restoration part
45 Appropriateness judgment part
46 Output device
100 2D code
| Aij | Modulation code matrix
Aij modulation element
｜ Bij | Binary data matrix
Bij element
Sij cell

Claims (2)

A method for creating a two-dimensional code in which one of two different colors is assigned to each element of an n-row, m-column matrix, and a plurality of binary original data matrices | Bij | For each element of (i = 1 to n, j = 1 to m−1), a modulation element obtained by a predetermined procedure so as to correspond to the first column to m−1th column of each element for each row Are sequentially assigned from the second column except for the first column, and the first column of modulation elements is set as a predetermined element, whereby a modulation code matrix | Aij | (consisting of binary elements corresponding to the two-dimensional code is set. i = 1 to n, j = 1 to m), and a two-dimensional code is created by applying coloring corresponding to each element of the modulation code matrix | Aij |
As the predetermined procedure, each row of the binary original data matrix | Bij | for each of the case where the modulation element in the first column of each row of the modulation code matrix | Aij | is “0” and “1”. For each binary element data matrix | Bij | corresponding to the modulation element, it is determined whether the element of the corresponding column is “0” or “1”. If the element of the corresponding column is “0”, the modulation is performed. While the element is the modulation element of the next column, and the element of the corresponding column is “1”, the modulation process of changing the modulation element of the next column to a modulation element different from the modulation element is performed, and the modulation of the first column One of the modulation processes when the element is set to “0” and “1” is selected, and the selection of the modulation process for each of the second and subsequent lines includes the current line and the previous line. The sum of the absolute values of the differences in the modulation elements between the columns is larger. How to create two-dimensional code and selects the halftone processing. A plurality of binary original data matrices | Bij, which is a sheet having a two-dimensional code in which either one of two different colors is given to each element of a matrix of n rows and m columns, and the original data is binarized For each element of | (i = 1 to n, j = 1 to m−1), a modulation element obtained by a predetermined procedure is modulated for each row so as to correspond to the first column to the m−1th column of the element. A modulation code matrix | Aij | composed of binary elements corresponding to the two-dimensional code is set by sequentially assigning elements from the second column excluding the first column of elements and setting the first column of modulation elements as a predetermined element. (I = 1 to n, j = 1 to m), and coloring corresponding to each element of the modulation code matrix | Aij |
The predetermined procedure is as follows. For each of the cases where the modulation element in the first column of each row of the modulation code matrix | Aij | is “0” and “1”, each row of the binary original data matrix | Bij | For each binary element data matrix | Bij | corresponding to the modulation element, it is determined whether the element of the corresponding column is “0” or “1”. If the element of the corresponding column is “0”, the modulation While the element is the modulation element of the next column, and the element of the corresponding column is “1”, the modulation process of changing the modulation element of the next column to a modulation element different from the modulation element is performed, and the modulation of the first column One of the modulation processes when the element is set to “0” and “1” is selected, and the selection of the modulation process for each of the second and subsequent lines includes the current line and the previous line. Modulation with the larger absolute value of the difference in modulation elements between each column Paper having a two-dimensional code, characterized in that is obtained by selecting a sense.

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