JP3499220B2 - Two-dimensional code, two-dimensional code reading method, program, and computer-readable recording medium - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-dimensional code and a method for reading the same, and more particularly to a two-dimensional code for improving data density, a method for reading the same, a program for causing a computer to execute the reading method, and a computer reading method. It relates to a possible recording medium.

[0002]

2. Description of the Related Art Conventionally, as a two-dimensional code, for example, as described in JP-A-7-168902,
A two-dimensional code that divides a two-dimensional data element into a plurality of two-dimensional arrays to display position information and density information on each core code, or as described in JP-A-7-254037. , An attempt has been made to improve the reading speed and reading accuracy when reading a symbol such as a CCD (Charge Coupled Device) image scanner such as a two-dimensional code formed by embedding a shape for position determination inside a two-dimensional matrix. It is known to have come.

[0003]

However, the above-mentioned attempts have been devised on the premise of the performance of the conventional one-dimensional bar code reader. Therefore, there is an advantage that the position determination information and the density information can be easily obtained, but when storing a large amount of information, the area occupied by the two-dimensional code also increases in proportion to the amount of information. It was On the other hand, due to recent technological innovation,
The performance has been remarkably improved by DSP (Digital Signal Processor), etc., and the reading accuracy has been dramatically improved due to the improvement of image processing technology and the development of high-resolution CCD elements, and information in a limited area. An environment is being set up in which high density can be achieved.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a two-dimensional code capable of increasing the density of information, a reading method therefor, a program for causing a computer to execute the reading method, and a computer-readable code. To provide a suitable recording medium.

[0005]

The present invention solves the above problems by the following means.

That is, according to the present invention, the binary data is symbolized into cells and arranged so as to form a two-dimensional matrix, and the first data area is arranged so as to surround the data area. A two-dimensional code including a pattern that provides information of data density of a region and positioning information, wherein the pattern has a first side and a second side that are adjacent to each other.
And a third side and a fourth side, respectively, which are adjacent to the first data area and are opposed to the first side and the second side, respectively, are arranged so as to be separated from the data area. A substantially rectangular solid line, a first protrusion portion and a second protrusion portion that are arranged at a predetermined pitch so as to extend outward from the first side and the second side, respectively, and the third protrusion. A third protrusion and a fourth protrusion arranged at a predetermined pitch so as to extend inward from the side and the fourth side toward the data area, the first side, and the second side. A fifth end and a sixth end arranged so as to extend the first side and the second side from a first end point that is an intersection point of the sides, and the first end point. And a seventh protrusion arranged so as to extend the fourth side from a second end point which is an end point of the first side different from When, wherein the third endpoint and the first end point is a terminal point of a different said second side, and the eighth of protrusions arranged so as to extend the third side, and
A two-dimensional code having no protrusion is provided at a fourth end point, which is an intersection of the third side and the fourth side.

According to the present invention, since the pattern for giving the data density and the positioning information is provided, even if the number of the binary data is increased and the occupied area of the data area is increased, a single pattern is used. The cell can be positioned with. As a result, the occupied area of the entire two-dimensional code can be made much smaller than a simple multiple of the amount of information stored in the data area. As a result, a two-dimensional code that stores a large amount of information at a high density is provided.

The first to eighth protrusions function as a header line for obtaining the data density and the positioning information in the read image. That is, the fifth and sixth protrusions are arranged at the first end points, the seventh and eighth protrusions are arranged at the second and third end points, respectively, while the fourth and sixth protrusions are arranged. Since the protrusion is not arranged at the end point, the fourth end point can be selected as a reference point for specifying the position coordinates of the cell in the read image. Further, since the first to fourth protrusions are arranged at the predetermined pitch on the rectangular solid line, the number of these protrusions is calculated to calculate the binary data encoded in the data area. It becomes possible to calculate the quantity. This makes it possible to obtain information on the data density in the data area. Further, by providing a straight line connecting the protrusions in the read image, it becomes possible to specify each position coordinate of the cell based on the coordinates of the intersection of these straight lines.

It is desirable that the line widths of the first to fourth sides and the widths of the first to eighth protrusions are set corresponding to the size of the cell.

The first protrusions have a pitch of a first length N (N) from the first end point toward the second end point.
Is a natural number) and the second protrusions are the first protrusions.
M (M is a natural number) are arranged at a pitch of a second length from the end point of the third end point toward the third end point, and the third protrusion extends from the third end point toward the fourth end point. Are arranged at the pitch of the first length and the fourth protrusions are arranged at the pitch of the second length from the second end point toward the fourth end point. It is good to be arranged.
The data capacity of the data area can be easily calculated by recognizing the first to fourth protrusions and specifying the specific numbers of N and M.

Further, according to the present invention, there is provided the above-described method for reading a two-dimensional code according to the present invention, wherein a procedure for obtaining an image of the two-dimensional code and a periphery of the obtained image are the above-mentioned edges. The fourth end point is touched and the seventh
Of cutting out a rectangular area surrounding the pattern so as to include at least a part of the protruding portion and at least a part of the eighth protruding portion, and the fourth end point, the seventh protruding portion, and the Each contact between the eighth protrusion and the peripheral edge of the rectangular area is specified as a first contact, a second contact, and a third contact, respectively, and the fifth or sixth protrusion and the peripheral edge of the rectangular area are specified. And a first line segment connecting the first contact and the second contact is set, and the first contact and the third contact are connected to each other. By setting a second line segment to be connected and setting a first virtual line parallel to the first line segment and moving the first virtual line from the fourth contact toward the third contact, A procedure for recognizing the first protrusion, the third protrusion, and the second side, and the second line segment By setting a parallel second virtual line and moving it from the fourth contact toward the second contact, the second protrusion, the fourth protrusion, and the first side are formed. And the recognized first to fourth steps
Of calculating the capacity of the binary data in the data area based on the number of protruding portions, and a coordinate system having the first line segment and the second line segment as the X axis or the Y axis or the rectangular area Of the sides forming the peripheral edge of the data area, a coordinate system in which two sides orthogonal to each other are used as the X axis or the Y axis, and the coordinates of each cell in the data area are specified; And a procedure for converting the generated binary data into bit string data, a method for reading a two-dimensional code is provided.

According to the two-dimensional code reading method, the position coordinates of each cell in the read image are specified based on the plurality of protrusions, so that the encoded binary data can be restored with high accuracy. it can. Further, since the capacity of the binary data in the data area is calculated based on the recognized number of the first to fourth protrusions, the data density of the data area can be easily and quickly acquired.

Further, according to the present invention, there are provided a program for causing the computer to execute the above-described two-dimensional code reading method, and a computer-readable recording medium recording the program.

[0014]

DETAILED DESCRIPTION OF THE INVENTION Some embodiments of the present invention will be described below with reference to the drawings.

(1) Embodiment of Two-Dimensional Code FIG. 1 is a schematic view showing an embodiment of a two-dimensional code according to the present invention. As shown in the figure, the two-dimensional code 1 of this embodiment is arranged so as to surround the matrix data part 2 and the matrix data part 2 in which the binarized data is stored in the form of bright and dark square cells. A square and heading lines (protrusions) R11 to R14, R21 to R formed by solid lines vertically extending from the sides a to d of the square, respectively.
23, R31 to R33, R41 to R43, R51 to R5
3 and 3. The quadrangle and the headlines R11 to R53 are patterns in the present embodiment, and thereby data density information and positioning information are given by using a reading method described later. The width of the rectangle and each heading line is the same as the length of one side of the data cell.

The headlines R11 and R12 are arranged so as to extend from the point D along the sides b and a, respectively. The headline R13 is arranged so as to extend the side d from the point B, and the headline R14 is arranged so as to extend the side c from the point C. These heading lines R11 to R14
Respectively correspond to the fifth to eighth protrusions in the present embodiment. Of the corners A to D of the quadrangle, the point A (fourth
(Corresponding to the end point of) is not provided with a headline. Thereby, as will be described later, the point A can be used as the origin of the two-dimensional code in the image processing in order to specify the position coordinates of each cell.

Heading lines R21 to R23, R31 to R3
3, R41 to R43 and R51 to R53 indicate the positions of the specific data cells in the row direction or the column direction, respectively. The heading lines R21 to R23 and R41 to R43 are arranged on the sides a and c of the quadrangle at a pitch P1 of a constant length, and correspond to the first protrusion and the third protrusion in the present embodiment, respectively. Further, headline lines R31 to R33, R51 to
The R53 are arranged on the sides b and d of the quadrangle at a pitch P2 of a constant length, and are arranged in the second embodiment in the second embodiment.
Correspond to the protrusion and the fourth protrusion. Pitch P1, P2
Each of the lengths is a known constant, and has the same value in this embodiment.

Heading lines R21 to R23, R31 to R33
Are arranged so as to extend outward from the sides a and b in a quadrangle. On the other hand, headline lines R41 to R4
3, R51 to R53 are arranged so as to extend inward of the quadrangle from the other adjacent two sides c and d. In the present embodiment, the lengths of the respective heading lines are all the same, but in order to prevent the heading lines R41 to R43 and R51 to R53 facing inward from overlapping the matrix data part 2, the side c,
d is arranged apart from the peripheral edge of the matrix data section 2.

The number of header lines can be increased or decreased independently in each of the horizontal and vertical directions depending on the number of data in the matrix data section. Therefore, it is possible to configure the two-dimensional code of various sizes and shapes depending on the usage of the data volume and the place to print. As described above, in the two-dimensional code 1 of this embodiment, the matrix data part 2
Since there is no special print pattern for cutting out, positioning, etc. inside, it is possible to mount more data in a small area. Further, even if the data capacity is increased, the cutting and positioning can be performed with a single pattern that surrounds the matrix data part 2. Therefore, the occupied area of the entire two-dimensional code is larger than the size proportional to the increase of the data capacity. Much smaller. As a result, a two-dimensional code that stores a large amount of information at a high density is provided.

(2) Embodiment of Two-Dimensional Code Reading Method Next, the two-dimensional code reading method shown in FIG. 1 will be described as an embodiment of the two-dimensional code reading method according to the present invention. Here, only the reading procedure peculiar to the two-dimensional code according to the present invention is shown, and the detailed procedures and adjustments generally required for the reading process are omitted.

FIG. 2 is an explanatory view of the reading method of this embodiment, and FIG. 3 is a flowchart showing a schematic procedure of the reading method shown in FIG.

1) First, the digital image data of the two-dimensional code 1 is taken in using an image pickup device such as a CCD (step S1).

2) Next, the distribution (histogram) in which vertical and horizontal dark cells exist in this image data is examined, and a rectangular area AR surrounding the two-dimensional code 1 is defined as shown in FIG. 2 (step S2). .

3) Next, a point which is in contact with each side of the peripheral edge of the rectangular area AR is searched (step S3). In the case of FIG.
Points A, E, F and H are obtained.

4) Next, the dots on the line segment connecting adjacent points of these points A, E, F, H are examined, and the dark solid line corresponds to which line segment of the sides a to d of the quadrangle. It is determined whether to do so (step S4). In the case shown in FIG. 2, line segment AE
And the line segment AF correspond to the solid lines of the sides d and c of the quadrangle, respectively. On the other hand, there is no corresponding solid line between the line segment EH and the line segment FH. The intersection A of the line segment AE and the line segment AF is selected as the origin of the two-dimensional code 1 (step S5).

5) Next, a line segment parallel to the line segment AF and having substantially the same length is examined from the point A to the point E, the line segment BH is specified, and the points B and H from the end points thereof are specified. Specify. Similarly, a line segment CG parallel to the line segment AE and having substantially the same length from the point A to the point F is examined, and the point C
And the point G, and the intersection D between the line segment BH and the line segment CG is specified (step S6).

6) Next, by setting a virtual broken line (heading broken line) parallel to the line segment AF and having the same length, starting from the point A, scanning in the direction of the point E with bd1, bd2 ... , Headlines R31 and R53, R32 and R52, R
33 and R51 are searched (step S7). At this time, a heading broken line bd1 connecting the heading lines R31 and R53
Since the distance from the point A to the point A and the length and pitch of each heading line are known constants with the size of the data cell as a unit, based on the positional relationship between the points A to D already specified in the above procedure. The position and length of each headline can be predicted.
Similarly, an imaginary broken line that is parallel to the line segment AE and has the same length is set, and the ac line is started in the direction from the point A to the point F.
By scanning 1, ac2, ..., Heading lines R23 and R43, R22 and R42, R21 and R41 are searched (step S7). Here, line segment AC (side c of the quadrangle)
Is the same as the number of heading lines recognized as extending vertically inward from the line segment and the number of heading lines recognized as extending vertically from the line segment BD (quadrangle side a) to the same. Yes, and similarly, the number of headline lines recognized to extend vertically inward from the line segment AB (quadrangle side d) and the line segment CD (4
If the number of heading lines recognized to extend vertically outward from the side b) of the polygon is the same, it can be confirmed that each heading line is normally searched. Further, as described above, since the number of headline lines is independently determined in each of the horizontal direction and the vertical direction according to the number of data in the matrix data portion 2, the headline recognized in each line segment (side). The capacity of the matrix data is determined according to the number of lines.

7) Then, as shown by the broken line in FIG.
A line segment bd1 that forms a lattice shape by sequentially connecting the points on the heading line recognized by the two parallel sides of the polygon.
~ Bd3, ac1 to ac3 are assumed again, and the coordinates of intersections n11 to n33 of these line segments are calculated (step S
8). These coordinates correspond to the coordinates of the data cells in the matrix data section 2 extracted at equal intervals.

8) Further, from the coordinates of the intersections obtained in 7) above, the coordinate value of each cell is obtained from the known number of cells between the header lines, and the binary value of each cell is sampled to obtain the bit string data. (Step S9).

9) Finally, since the error correction code is added in advance to the bit string data of the two-dimensional code 1, error correction is performed using this. As a result, the original data is restored (step S10).

As described above, according to the two-dimensional code reading method of the present embodiment, the data stored in the matrix data section 2 can be restored with high accuracy by simple image processing, and the data capacity can be quickly increased. Can be obtained.

(3) Program and Recording Medium The series of procedures of the two-dimensional code reading method described above may be incorporated into a program and read by a computer capable of processing image data to be executed. As a result, the two-dimensional code reading method according to the present invention can be realized using a general-purpose computer. Further, a series of procedures of the above-mentioned two-dimensional code reading method may be stored in a recording medium such as a flexible disk or a CD-ROM as a program to be executed by a computer capable of processing image data, and may be read and executed by the computer. . The recording medium is not limited to a portable one such as a magnetic disk or an optical disk, and may be a fixed recording medium such as a hard disk device or a memory. Further, a program incorporating a series of procedures of the above-described two-dimensional code reading method may be distributed via a communication line (including wireless communication) such as the Internet.
Furthermore, a program incorporating a series of procedures of the above-mentioned two-dimensional code reading method may be encrypted, modulated, or compressed in a state in which it is stored in a recording medium via a wired or wireless line such as the Internet. It may be stored and distributed.

Although some of the embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments.
Needless to say, various modifications can be made within the technical scope.

[0034]

As described above in detail, the present invention has the following effects.

That is, according to the two-dimensional code of the present invention, the substantially rectangular pattern is provided so as to surround the data area and provided with a plurality of protrusions for giving the data density and the positioning information of the data area. Therefore, regardless of the amount of data stored in the data area, each cell can be positioned by a single pattern. As a result, a two-dimensional code that stores a large amount of information and has high reading accuracy is provided.

Further, according to the two-dimensional code reading method of the present invention, since the position coordinates of each cell in the read image are specified based on the plurality of protrusions, the encoded binary data can be obtained with high accuracy. Can be restored.
Further, since the procedure for calculating the capacity of the binary data in the data area is provided based on the recognized number of the first to fourth protrusions, the data density of the data area can be easily and quickly acquired. it can.

Further, according to the program and the computer-readable recording medium of the present invention, the above-mentioned two-dimensional code reading method can be executed using a general-purpose computer.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an embodiment of a two-dimensional code according to the present invention.

FIG. 2 is an explanatory diagram of an embodiment of a two-dimensional code reading method according to the present invention.

FIG. 3 is a flowchart illustrating a schematic procedure of the reading method shown in FIG.

[Explanation of symbols]

1 Two-dimensional code 2 Matrix data part a to quadrangle sides bd1 to bd3, ac1 to ac3 Virtual broken lines P1 and P2 Pitches R11 to R14, R21 to R23, R31 to R33, R between heading lines
41-R43, R51-R53 Headline (projection)

Front page continued (72) Inventor Satomi Mizoguchi 2-21-32 Nakazato, Ninomiya-machi, Naka-gun, Kanagawa Dia Palace Shonan Hills Ninomiya 402 (56) Reference JP-A-11-306272 (JP, A) JP-A-11 -328301 (JP, A) JP-A-11-312215 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G06K 7/10

Claims (7)

(57) [Claims] 1. A data area in which binary data is symbolized into cells and arranged so as to form a two-dimensional matrix; and a data area which is arranged so as to surround the first data area and in which data density information of the data area is provided. And a pattern for providing positioning information, wherein the pattern has a first side and a second side that are adjacent to each other, the first side and the second side being adjacent to each other, and the first side and the second side. A substantially rectangular solid line with a third side and a fourth side facing each other spaced apart from the data area, and extending outward from the first side and the second side. A first protrusion portion and a second protrusion portion that are respectively arranged at a predetermined pitch, and a predetermined pitch so as to extend inward from the third side and the fourth side toward the data area. A third protrusion and a fourth protrusion arranged, The fifth protrusion and the sixth protrusion arranged so as to respectively extend the first side and the second side from a first end point that is an intersection of the first side and the second side. A protrusion; a seventh protrusion arranged to extend the fourth side from a second end that is an end of the first side different from the first end; An eighth projecting portion arranged to extend the third side from a third end point which is an end point of the second side different from the end point, and the third side and the third side A two-dimensional code in which no protrusion is arranged at the fourth end point, which is the intersection with the side of 4. 2. The line widths of the first to fourth sides and the widths of the first to eighth protrusions are set in correspondence with the size of the cell. The two-dimensional code shown. 3. The first protrusions have a pitch of a first length N (N) from the first end point toward the second end point.
Is a natural number), and the second protrusions are arranged M (M is a natural number) pieces at a pitch of a second length from the first end point toward the third end point. N protrusions are arranged at a pitch of the first length from the third end point toward the fourth end point, and the fourth protrusions are arranged from the second end point to the second end point. The two-dimensional code according to claim 1 or 2, wherein the M pieces are arranged at a pitch of the second length toward an end point of No. 4. 4. The two-dimensional code according to claim 3, wherein each of the first length and the second length is set corresponding to a size of the cell. 5. The method for reading a two-dimensional code according to any one of claims 1 to 4, wherein a procedure for obtaining an image of the two-dimensional code, and a periphery of the obtained image is the first A step of cutting out a rectangular area surrounding the pattern so as to include at least a part of the seventh protrusion and at least a part of the eighth protrusion while being in contact with the end point of 4; The contact points of the end point, the seventh protrusion portion and the eighth protrusion portion, and the peripheral edge of the rectangular region are specified as a first contact point, a second contact point, and a third contact point, respectively, and the fifth or the fifth contact point is specified. The procedure of recognizing the contact point between the protruding portion of 6 and the peripheral edge of the rectangular area as a fourth contact point, and the first line segment connecting the first contact point and the second contact point are set to set the first contact point. A second connecting the third contact and the third contact
Of setting the first line segment and moving the first virtual line parallel to the first line segment in the direction from the fourth contact point to the third contact point. Protrusion, the third protrusion, and the second
And a second virtual line parallel to the second line segment and moved from the fourth contact toward the second contact, Protrusion, the fourth protrusion, and the first
Of the sides, a step of calculating the capacity of the binary data in the data area based on the recognized numbers of the first to fourth protrusions, and one of the sides forming the periphery of the rectangular area. A procedure of setting a coordinate system having two sides orthogonal to each other as an X-axis or a Y-axis to specify the coordinates of each cell in the data area; and the binary data encoded as bit string data based on the cell coordinates. A method of reading a two-dimensional code, comprising: 6. A procedure for acquiring an image of the two-dimensional code according to claim 1, wherein a peripheral edge is in contact with the fourth end point in the acquired image, and the seventh A step of cutting out a rectangular area surrounding the pattern so as to include at least a part of a protrusion and at least a part of the eighth protrusion, and the fourth endpoint, the seventh protrusion and the 8 points of intersection of the protrusion and the peripheral edge of the rectangular region are specified as a first contact point, a second contact point and a third contact point, respectively, and the fifth or sixth protrusion portion and the peripheral edge of the rectangular region are specified. And a first line segment connecting the first contact point and the second contact point is set, and the first contact point and the third contact point are connected. Second
And a step of setting a first virtual line parallel to the first line segment and moving the first virtual line in the direction of the third contact point. The step of recognizing the protrusion and the second side, and by setting a second virtual line parallel to the second line segment and moving the second virtual line toward the second contact, And a procedure for recognizing the fourth protrusion and the first side, and calculating the capacity of the binary data in the data area based on the number of the recognized first to fourth protrusions. And a step of specifying a coordinate system of each cell in the data area by setting a coordinate system in which two sides that are orthogonal to each other among the sides forming the periphery of the rectangular area are set as the X axis or the Y axis. A procedure for converting the encoded binary data into bit string data based on the coordinates. Program for executing the, the reading method of the two-dimensional code comprising a computer. 7. A procedure for acquiring an image of the two-dimensional code according to claim 1, wherein a peripheral edge is in contact with the fourth end point in the acquired image, and A step of cutting out a rectangular area surrounding the pattern so as to include at least a part of a protrusion and at least a part of the eighth protrusion, and the fourth endpoint, the seventh protrusion and the 8 points of intersection of the protrusion and the peripheral edge of the rectangular region are specified as a first contact point, a second contact point and a third contact point, respectively, and the fifth or sixth protrusion portion and the peripheral edge of the rectangular region are specified. And a first line segment connecting the first contact point and the second contact point is set, and the first contact point and the third contact point are connected. Second
And a step of setting a first virtual line parallel to the first line segment and moving the first virtual line in the direction of the third contact point. The step of recognizing the protrusion and the second side, and by setting a second virtual line parallel to the second line segment and moving the second virtual line toward the second contact, And a procedure for recognizing the fourth protrusion and the first side, and calculating the capacity of the binary data in the data area based on the number of the recognized first to fourth protrusions. And a step of specifying a coordinate system of each cell in the data area by setting a coordinate system in which two sides that are orthogonal to each other among the sides forming the periphery of the rectangular area are set as the X axis or the Y axis. A procedure for converting the encoded binary data into bit string data based on the coordinates. When the computer-readable recording medium recording a program for executing a method of reading the two-dimensional code to the computer with a.