JPH11312215A - Two-dimensional code decoder and storage medium thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the segmenting/reading time of a two-dimensional code and also to improve the data error detection reliability of the two-dimensional code by forming the two-dimensional code by arranging plural inner cells as the processing units and using a series of code data, including a specific cell to form each inner cell. SOLUTION: A two-dimensional code consists of plural inner cells which are arranged as the processing units, and each inner cell consists of a series of code data, including error detection cells and recognition pointer cells. As a result, a reading means is able to the two-dimensional code by each inner cell and also segment each inner cell by identifying the position of each of recognition pointer cells which constitute an inner cell and deciding the reading position of the inner cell. In such a constitution of a two-dimensional code decoder, an inner cell 10, for example, consists of a pointer cell PO1, separator cells S0 to S3, parity cells P0 to P3 and data cells D0 to D15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a two-dimensional code decoding device for reading and decoding a two-dimensional code, and a storage medium.

[0002]

2. Description of the Related Art Generally, as means for inputting data to a computer or the like, for example, there are various means for optically reading, from OMR such as punch cards and mark sheets to OCR for reading characters as they are. Among them, bar codes are widely used as a kind of symbol codes, and are used for inputting data in sales management, distribution management, production management, and the like.

Various types of barcodes have been proposed, developed, and improved from the invention of the barcode to the present, and it is no exaggeration to say that the barcode as a one-dimensional code has been almost completed.

[0004] Under such circumstances, the information that can be encoded by a one-dimensional barcode is limited, and a two-dimensional barcode has been developed in response to a desire to encode more information. However, since the two-dimensional barcode was based on the idea of simply stacking one-dimensional barcodes, it only increased the amount of information and information density several times. there were.

On the other hand, a matrix type two-dimensional code having a large amount of information and a large information density has been developed. The two-dimensional code is composed of a data cell containing data and a timing cell serving as a reference when reading the code. The data cell is read based on the timing cell to determine a data value. For this reason, it is necessary to determine the data value by inferring the direction and the distortion when the two-dimensional code is sensed by the area sensor and the like from the direction of the timing cell and the distortion. In addition, when sensing a two-dimensional code with an area sensor or the like, regarding the extraction of data as to which part is determined as a two-dimensional code, a square around the matrix of the two-dimensional code, or to easily determine the direction, There is a method of enclosing in an L-shaped frame and setting it as a cutout frame pattern. When this rectangular frame pattern or L-shaped frame pattern is detected, it is determined that it is a two-dimensional code, and it is inferred from those frame patterns. And cut out the two-dimensional code.

[0006]

However, when detecting a two-dimensional code surrounded by a rectangular frame pattern, the angle at which sensing is performed by an area sensor or the like, and whether the point at which sensing starts is a vertex or a side of the square, etc. Therefore, there is a problem that it takes time to detect a two-dimensional code. Also, in the case of an L-shaped frame pattern, the method of cutting is different between the case where the frame is read from the L-shaped side where the frame is a solid line and the case where the frame is read from the opposite side of the L-shaped where the frame is blank. There was a problem that it took time to detect the code.

Further, when reading each data cell because the data cell and the timing cell are separated, it is necessary to judge the value based on the separated timing cell. Even in such a case, even if it is impossible to read, or even if it can be read, it often relies on data correction using an error correction code (ECC), and it takes a lot of time to decode. Was.

Further, when sensing a two-dimensional code with an area sensor, it is usually difficult for the user to know which part of the two-dimensional code is being sensed, and the two-dimensional code is correctly read in the sensing range of the area sensor. Was difficult. In addition, the conventional two-dimensional code, since it is not possible to cut out data and detect data errors without reading the entire code, even if shortening the decoding time, from the sense by the area sensor that depends on the user operation, There was a limit to the reduction of the total time required to extract and decode the two-dimensional code.

SUMMARY OF THE INVENTION An object of the present invention is to provide a two-dimensional code decoding apparatus and a storage medium for shortening the time required to cut out and read a two-dimensional code and improving the reliability of detecting a data error of the two-dimensional code. That is.

[0010]

According to the first aspect of the present invention,
In a two-dimensional code decoding device that reads and decodes a two-dimensional code, the two-dimensional code includes: an error detection cell for detecting an error in code data expanded in the two-dimensional code; A series of code data including a recognition pointer cell for recognizing the developed position is defined as a middle cell, and the middle cell is arranged as a plurality of processing units of two-dimensional code data to be decoded, and the two-dimensional code is read. Reading means for identifying the read position of each of the medium cells based on the recognition pointer cell and reading the two-dimensional code; and based on the error detection cells included in each of the medium cells read by the reading means. Then, an error portion in the code data to be decoded is detected for each of the medium cells, and the code data in the two-dimensional code is detected. It is characterized by comprising a decoding means for decoding in units of cells, a.

According to the two-dimensional code decoding device of the present invention, the two-dimensional code is constituted by arranging the plurality of middle cells with the middle cells as processing units. Each of the arranged middle cells is composed of a series of code data including the error detection cell and the recognition pointer cell. For this reason, the reading means can read the two-dimensional code in units of medium cells,
By identifying the position of each of the recognition pointer cells constituting each of the middle cells and determining the read position of each of the middle cells, each of the middle cells can be cut out.

Therefore, since the two-dimensional code can be cut out and read for each medium cell constituting the two-dimensional code, it is not necessary to cut out and read all the two-dimensional codes at once. Further, by performing a plurality of cutting and reading processes in units of medium cells in parallel, the time for cutting and reading can be reduced. In addition, even when the two-dimensional code is distorted, cutting and reading can be performed within a range that does not affect the respective middle cells.

The decoding means detects the error in the code data to be decoded for each of the medium cells based on the error detection cells constituting the medium cell, and decodes the code data in the two-dimensional code. Decode in medium cells. Therefore, since a data error can be detected in units of middle cells, the range of data errors can be specified in the range of the middle cells of the two-dimensional code, and the reliability of data error detection can be improved. In addition, since the decoding means decodes the medium cells in units, the decoding time can be shortened by performing decoding processing on the plurality of read medium cells in parallel.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIGS. 1 to 8 show a computer system according to a first embodiment of the present invention.

First, the configuration will be described.

FIG. 1 is a block diagram showing a main configuration of a computer system 1 according to the first embodiment. In FIG. 1, the computer system 1 has a C
It comprises a PU 2, a RAM 3, a storage device 4, a storage medium 5, a display unit 6, an input unit 7, and an area sensor 8, and each unit except the storage medium 5 is connected by a bus 9.

CPU (Central Processing Unit) 2
Develops an application program specified from a system program stored in the storage device 4 and various application programs corresponding to the system into a program storage area (not shown) in the RAM 3 and is input from the input unit 7. Various instructions or data are temporarily stored in the RAM 3, various processings are executed in accordance with the application instructions stored in the storage device 4 in accordance with the input instructions and the input data, and the processing results are stored in the RAM 3. Are displayed on the display unit 6. Then, the processing result stored in the RAM 3 is stored in a storage destination in the storage device 4 designated by the input unit 7.

In the image data processing, the CPU 2 recognizes an electric signal input from the area sensor 8 as image data, detects whether or not a frame described later exists in the image data, and cuts out a frame if it exists. And a process of extracting a two-dimensional code. Further, the black area at the corner of the cut-out two-dimensional code is determined as a pointer cell, and a middle cell described later is cut out, and the position and color of each small cell described later in the middle cell are detected. Judge the data.

The CPU 2 performs a data error detection process based on a value of a parity cell, which will be described later, among the detected data of each small cell.

The input unit 7 includes a keyboard and a pointing device such as a mouse provided with a cursor key, numeral input keys, various function keys, and the like.
Output to The display unit 6 is a CRT (Cathode Ray Tube)
And the like, and displays display data (image data of the area sensor, decoding result of a two-dimensional code, etc.) input from the CPU 2.

A RAM (Random Access Memory) 3 is a C
When the PU 2 forms the program storage area for developing various data when executing the various application programs, and when the CPU 2 executes the image data processing, it expands the electric signal input from the area sensor 8. A frame for extracting a two-dimensional code, and a memory area for developing the position, color, data, etc. of each small cell constituting the middle cell, which will be described later, are formed.

The storage device 4 has a storage medium 5 in which programs, data and the like are stored in advance, and this storage medium 5 is constituted by a magnetic or optical storage medium or a semiconductor memory. The storage medium 5 is fixedly provided in the storage device 4 or is detachably mounted. The storage medium 4 includes the system program, various application programs corresponding to the system, an image data processing program, It stores a two-dimensional code cutout processing program, data processed by various processing programs, and the like.

The program, data, and the like stored in the storage medium 4 may be configured to be received and stored from another device connected via a communication line or the like. A storage device having the storage medium may be provided on another connected device side, and the program and data stored in the storage medium 4 may be used via a communication line.

Next, the area sensor 8 will be described with reference to FIG. FIG. 2 shows a configuration of the computer system 1 centering on the area sensor 8. In FIG.
The RAM 3, the storage device 4, the storage medium 5, the display unit 6, the input unit 7, and the bus 9 are not shown for easy understanding. In FIG. 2, the area sensor 8 is, for example, a CC.
Like D (Charge-Coupled Devices), a photodiode is arranged on a line or a plane, and a light receiving unit for measuring the intensity of light, a focus control unit using a lens or the like for improving the accuracy at the time of receiving light, A well-known device which comprises a scanning unit for sequentially scanning the light receiving unit, an A / D conversion circuit for digitizing an electric signal output from the light receiving unit through the scanning unit, and the like, and converts an optical signal into an electric signal. It is. CPU2
Performs image recognition processing from an electric signal output from the area sensor 8, performs detection of a two-dimensional code, detection of data error, and decoding, which will be described later, and changes the aperture stop of the area sensor 8. Output a control signal for causing the

FIG. 3 is a diagram showing a basic configuration of the middle cell 10 included in the two-dimensional code processed in the first embodiment.

In the two-dimensional code, the method of expressing one bit, which is the minimum data structure, is as follows. In FIG. 3, the minimum unit square is one cell, and when the color of this cell is black, "1" is used. The case of white is represented as “0”. Book first
In this embodiment, this cell is called a small cell. A block in which the small cells are configured as 5 vertical cells × 5 horizontal cells will be referred to as the middle cell 10.

As shown in FIG. 3, the middle cell 10
1 ”, four separator cells“ S0 to S3 ”, four parity cells“ P0 to P3 ”, and 16 data cells“ D0 to D15 ”. Have been.

Here, the pointer cell PO1 is always set to black. The pointer cell PO1 is used to cut out a middle cell 10 of 5 × 5 cells, which will be described later, and to use the data cell after cutting. Used for detecting D0 to D15 and parity cells P0 to P3. The separator cells S0 to S3 are always set to white. This is to make the small cell adjacent to the black pointer cell PO1 white when making a two-dimensional code by arranging a plurality of middle cells 10 described later, so that the pointer cell PO1 can be easily detected.

The parity cell P0 is the data cell D0.
To D7, and the parity cell P
1 is the parity bit of data cells D8 to D15, and parity cell P2 is the data cells D0, D1, D4, D5, D
8, D9, D12, and D13, and parity cell P3 is a data cell D2, D3, D6, D7, D1.
0, D11, D14, and D15 represent parity bits.

With these parity cells P0 to P3,
When the data of the data cells D0 to D15 is black and white inverted due to dirt or the like, a data error described later is detected in the category of the middle cell 10, and two parity cells are targeted for one data cell. Thereby, the reliability of data error detection is improved. Data cell D
Numerals 0 to D15 are small cells representing binary data, in which actual data to be represented by a two-dimensional code is stored.

FIG. 4 shows a method for detecting a data error in the middle cell 10. The middle cells 10-1, 10-2, and 10-3 show cases of detectable data errors, and 10-4 shows the case of undetectable data errors. The middle cell 10-1 shows a case where the data cell D6 has a data error, and the error is detected by the parity cells P0 and P3 which are the parity bits of the data cell D6. Similarly, the middle cell 10
-2 indicates a case where the data cells D6 and D9 have an error, and the error is detected by the parity cells P0, P1, P2, and P3. Similarly, in the middle cell 10-3, the case where the data cells D5 and D6 have an error is shown. As described later, the parity cell P0 cannot be detected, but the error is detected by the parity cells P2 and P3.

However, in the middle cell 10-4, although the data cells D4 and D5 have an error, no error can be detected using any parity cell. This is because, as is well known, the parity bit is a determination bit of whether the number of bits 1 of the target data is an even number or an odd number. In the case of the middle cell 10-4, the data cells D4 and D5 which are data errors are an even number of data errors for the parity cell P0 serving as the parity bit and cannot be detected. Similarly, the parity cell P2
For even number of data errors and cannot be detected,
A data error in the middle cell 10-4 cannot be detected.

Here, when the middle cell 10-3 is reviewed again, if the data cells D5 and D6 are erroneous, an even number of data errors will occur for the parity cell P0 serving as the parity bit, and the data cannot be detected as described above. , The data cells D5 and D6 are the parity cells P2 and P2, respectively.
3, the data error is detected by the parity cells P2 and P3. As described above, in the rare case where there are a plurality of data errors in the middle cell, and there is an even number in the parity cell, and there is an even number in the other parity cells of the data error, it is rare. As described above, as described above, two parity cells are targeted for one data cell, and one parity cell is assigned to eight data cells, thereby improving the reliability of data error detection. Have improved.

FIG. 5 shows a two-dimensional code 100 according to the first embodiment constituted by middle cells 10 to 90. The two-dimensional code 100 is configured by arranging the middle cells 10 sequentially in the same direction. Here, a method of cutting out the middle cell will be described by taking the middle cell 10 as an example. As described above, the separator cells 10-PO1 to 90-PO1 of the middle cells 10 to 90 are black, and are arranged at positions that are easily detected by the adjacent white separator cells. The range of the middle cell 10 is indicated by the respective pointer cells 20-PO1, 40-PO1, and 50-PO1 of the adjacent middle cells 20, 40, and 50. The size of the pointer cell is one small cell, and the distance between the pointer cells is 4 small cells.
Therefore, the middle cell 10 can easily and accurately cut out the middle cell 10 based on its own pointer cell 10-PO1. Thus, other middle cells can be cut out in the same manner.

FIG. 6 shows the two-dimensional code 100 according to the first embodiment surrounded by a frame 150 according to the first embodiment. As shown in FIG. 6, a frame 150 according to the first embodiment is provided.
Is a white frame with a small cell width around the two-dimensional code 100 of the first embodiment, and a black frame with a small cell width surrounding the white frame. Frame 15 with 2D code 100
By enclosing the two-dimensional code 100, the two-dimensional code 100 can be cut out at high speed. This means that if there is no frame 150,
To cut out the two-dimensional code 100, use the two-dimensional code 10
Since it was necessary to perform the cutout while recognizing the difference from characters, pictures, etc. existing around 0, it took a lot of time.
This is because the cutout of 0 is replaced by the cutout of the frame 150, and the cutout can be easily performed because the frame 150 is a specific pattern having the above-described configuration.

Next, the operation will be described.

The two-dimensional code detection process executed by the CPU 2 in the computer system 1 according to the first embodiment will be described with reference to the flowchart shown in FIG.

First, the frame 150 containing the target two-dimensional code 100 is sensed by the area sensor 8, and the obtained image data is analyzed by the CPU 2 to cut out the frame 150 (step S1). Further, the CPU 2 cuts out the two-dimensional code 100 by removing the black frame and the white frame of the frame 150 from the image data of the frame 150 including the cut-out two-dimensional code 100 according to the above configuration (step S1).

At this time, the image data sensed by the area sensor 8 is temporarily stored in a memory area in the RAM 3, and the stored image data is read and analyzed by the CPU 2. Thereafter, data similarly analyzed by the CPU 2 is appropriately stored in a memory area in the RAM 3.

Next, the CPU 2 executes the two-dimensional code 10
With the configuration of the 0 and the middle cell 10, the black area existing at the corner of the two-dimensional code 100 detected in step S1 is determined as the pointer cell A (step S2), and the size of the black area determined as the pointer cell A is determined. The size is determined as one small cell (step S3).

Further, the CPU 2 executes the two-dimensional code 100
Is determined as the pointer cell B in the vertical direction of the five small cells whose size has been determined in step S3. Similarly, it is determined that the black area of five small cells in the horizontal direction is the pointer cell C, and the black area of five small cells in the horizontal direction from the pointer cell B is the pointer cell D (step S4). .

Next, the CPU 2 obtains the center address of the pointer cell A determined in step S3 (step S3).
5), the pointer cells A, B,
The area surrounded by C and D is determined to be the middle cell 10, and the pointer cell A and the pointer cell B are determined by the structure of the middle cell 10.
Are determined to be equal intervals for four small cells, and the parity cell 2
The color of the portion corresponding to the two center addresses is determined, and is set as the value of each of the two parity cells (step S6).

Subsequently, similarly, the CPU 2 operates the middle cell 1
As in the configuration of 0, the center address of each of the other parity cells and data cells of the middle cell is determined from the pointer cells A, B, C, and D, the color of the corresponding location is determined, and the value is determined ( Step S7).

By replacing the pointer cells B, C, or D with the pointer cells A (step S9), the middle cells including the pointer cells are similarly cut out from the pointer cells, and the small cells constituting the middle cells are similarly cut out. By repeatedly determining the cell value, the two-dimensional code 100
Detect code.

As described above, in the computer system 1 of the first embodiment, the CPU 2
0, the frame 150 is the two-dimensional code 100
, The two-dimensional code 100 can be easily cut out by detecting the frame 150 from the image data sensed by the area sensor 8.

The detected two-dimensional code 100 is a medium cell 10 composed of 25 small cells of 5 × 5.
Are arranged in a plurality.
Is a pointer cell P indicating the location of each medium cell 10.
O1, the pointer cell PO when a plurality of middle cells 10 are arranged.
Separator cells S0 to S3 to facilitate detection of 1
Since the data cells D0 to D15 corresponding to the actual data of the two-dimensional code 100 and the parity cells P0 to P3 for detecting data errors in the data cells D0 to D15 are used, the CPU 2 executes The cell 10 is cut out, and data of all the small cells of the two-dimensional code 100 is detected.

The CPU 2 cuts out the middle cell 10 from the detected two-dimensional code 100,
1, the pointer cell PO1 of the adjacent middle cell 10 is used.
Therefore, by determining the boundary of the middle cell 10, the middle cell 10 can be easily cut out. Further, the CPU 2 obtains the center address of the pointer cell PO1 of the middle cell 10,
Since the middle cell 10 is composed of 25 small cells of 5 × 5, the address of each cell is determined and data is detected. Similarly, the CPU 2 cuts out the other middle cell 10, detects data of each cell constituting the middle cell 10, and detects all data of the two-dimensional code 100. By using the parity cells P0 to P3 of the middle cell 10, the CPU 2 can detect a data error in the data cells D0 to D15.

Therefore, the CPU 2 can easily cut out the two-dimensional code 100 by cutting out the frame 150 from the image data sensed by the area sensor 8, and the two-dimensional codes 100 are arranged at equal intervals. A plurality of middle cells 10 constituting the two-dimensional code 100 can be easily cut out from the pointer cell PO1. Further, the CPU 2 easily detects the data of each cell from the configuration of the cut-out middle cell 10 and also detects the parity cell P0.
It is possible to detect whether or not there is a data error according to # 3.

Although the frame 150 surrounds the two-dimensional code 100 in order to cut out the two-dimensional code 100, the frame 150 is printed at the same time as when printing an image such as the two-dimensional code 100 or the like that requires pattern recognition, or before and after printing. Can be applied to other than the two-dimensional code 100 by printing or enclosing the frame 150, and the configuration of the frame 150 can be black and white.
Although the frame has a small cell width, as shown in FIG. 8, it may be a frame line of another line type such as a thin line, a thick line, or a multiple line. To make it possible, the line width and line type of each side of the frame may be changed.

In the method of detecting the two-dimensional code 100, the black area existing at the corner of the two-dimensional code 100 is determined to be the pointer cell PO1, and the middle cell 10 is started to be cut out. Since there are a plurality of small cells at equal intervals, the two-dimensional code 100
May be started to be cut out from the pointer cell PO1 other than the corner.

(Second Embodiment) Next, a computer system according to a second embodiment will be described.

The main configuration of the computer system according to the second embodiment is the same as the main configuration of the computer system according to the first embodiment. The difference from the first embodiment is the two-dimensional code detection processing executed by the CPU in the computer system. This processing will be described with reference to FIG.

FIG. 9 is a schematic diagram of an image in which the area sensor 8 captures the two-dimensional code 100 according to the second embodiment. As described above, the area sensor 8 includes a light receiving unit, a scanning unit,
As is well known, the light receiving unit detects the light intensity for each square grid called a pixel as shown in FIG. In general, the size of the minimum unit cell that forms the two-dimensional code is sufficiently larger than one pixel, and thus the two-dimensional code 100 according to the second embodiment is configured as shown in FIG. The size of the small cell is also larger than one pixel of the area sensor 8.

In FIG. 9, the two-dimensional code 100 is not in a parallel position with respect to the area sensor 8, but when the user senses the two-dimensional code 100 with the area sensor 8, it is difficult and time-consuming to sense the two-dimensional code 100 in parallel. Therefore, in most cases, the sensing is performed diagonally as shown in FIG.

The CPU 2 analyzes the image data sensed by the area sensor 8 and cuts out the frame 150 and the two-dimensional code 100.
The black area existing at the corner of 00 is determined as a pointer cell,
The middle cell is cut out, the position and color of each small cell constituting the middle cell are detected, and the data of each small cell is determined. The image data of the two-dimensional code 100 used for detecting the position of each small cell is data of a pixel developed on the RAM 3 and detected by the area sensor 8.
The method of detecting the position of the small cell is described in detail in CPU2.
However, a pixel serving as a center address of a small cell is obtained, and the color of the pixel is determined to be a data value of the small cell.

In the computer system according to the second embodiment, when obtaining the center address of this small cell,
By moving the entire image data of the two-dimensional code 100 developed on the RAM 3 by one pixel in the left-right direction and performing a logical AND operation of the colors at the respective pixel positions before and after the movement, the white pixels in the left-right direction are obtained. The adjacent black pixel is set to white, and the image data of the pixel is rewritten. Similarly,
The image data is moved up and down by one pixel, and a logical AND operation of the colors at the pixel positions before and after the movement is performed. rewrite. Moving the image data up, down, left, and right by one pixel and performing a logical operation on the color of the pixel before and after the movement is referred to as “shaking the image data”.

By shaking the image data in this manner, the number of black pixels is reduced. After swinging the image data, the CPU 2 detects the address of the small cell. For example, when obtaining the center address of a pointer cell for cutting out a middle cell, the number of black pixels occupying the pointer cell is one pixel around by shaking the image data because the pointer cell is adjacent to a white separator cell. Because it is running low
The pixel corresponding to the center address can be detected more easily and faster than before shaking the image data.

Similarly, the CPU 2 similarly detects a pixel corresponding to the center address of another small cell and sets it as the value of the small cell. As described above, when a white cell is adjacent, the number of pixels is small. Therefore, the pixel at the center address can be easily and quickly detected. Further, when the two-dimensional code 100 has dirt or the like, the dirt can be eliminated or reduced by shaking the image data, thereby preventing erroneous detection of the data.

As described above, in the computer system according to the second embodiment, when detecting the center address of each small cell constituting each medium cell of the two-dimensional code, the entire image data of the two-dimensional code is converted to one. Move up, down, left and right by pixels,
Since the logical operation of the color at the pixel position before and after the movement is performed, the number of the pixels in each small cell can be reduced. Therefore, the pixel corresponding to the center address of the small cell can be easily and quickly detected. In addition, when there is dirt or the like, the dirt can be erased or reduced, thereby preventing erroneous detection of data.

Although the image data is shaken for one pixel, the image data may be moved by a plurality of pixels within a range where the pixel of the small cell is not lost. In this case, the number of pixels of the small cell is further increased. By reducing the number, the center address of the small cell can be detected more easily and faster. In addition, since the image data can be shaken by a predetermined process, a control unit for performing the process may be provided, and the process may be executed as hardware. In this case, the process may be executed at higher speed. It is possible.

(Third Embodiment) Next, a computer system according to a third embodiment will be described.

The main configuration of the computer system according to the third embodiment is the same as the main configuration of the computer system according to the first embodiment, and therefore, the description is omitted. Further, the difference from the first embodiment is the process of cutting out a frame including a two-dimensional code and the configuration of the frame, which are executed by the CPU in the computer system. This will be described using 10 to 12.

FIG. 10 shows a circular pattern constituting a frame 200 described later of the third embodiment. As shown in FIG. 10, the circular pattern 10-A is a circle, and 10-B is
It is a black circle, 10-C is a black donut-shaped concentric circle, and 10-D is a double line circle.

FIG. 11 shows a frame 200 according to the third embodiment. The frame 200 has a circular pattern 10-A at the upper left corner, a circular pattern 10-B at the upper right corner, and a circular pattern 10-C at the lower left corner of the corners of the frame 150 of the first embodiment.
Is arranged in a circular pattern 10-D at the lower right corner. As described above, since the four corners of the frame 200 have different circular patterns, the top, bottom, left, and right directions and the front and back of the frame 200 including the two-dimensional code can be easily determined.

The extraction of the two-dimensional code is to extract the frame 200 as in the first embodiment.
Since the circular pattern is arranged at the four corners of the frame 200, the frame 200 can be easily cut out by detecting the circular pattern. Further, the circular pattern is a pattern in which one or a plurality of circles are configured as concentric circles.
As shown in FIG. 2, the same circular pattern is obtained regardless of which direction the sensing is performed by the area sensor.
For this reason, it is not necessary to consider the processing in the case of oblique sensing, and the recognition program for the circular pattern can be simplified, so that the memory capacity for the recognition processing can be reduced and the processing speed can be increased. .

Next, the process of the CPU 2 cutting out the frame 200 will be described. The CPU 2 first determines the circular patterns 10-A to 10-A from the image data sensed by the area sensor.
10-D is detected. Even when the frame 200 is image data sensed diagonally, the circular patterns 10-A to 10-A
O-D can be easily and quickly detected because of the above configuration.
The CPU 2 also detects the detected circular patterns 10-A to 10-A-1.
The top, bottom, left, right, front and back of the frame 200 are determined from the position of 0-D. Next, frame 2 connecting patterns 10-A to 10-D
By detecting the range of 00, it is possible to cut out the frame 200 and cut out the two-dimensional code.

As described above, in the computer system according to the third embodiment, the frame 200 has the circular pattern 10-.
A to 10-D are arranged at four corners, and since this circular pattern is composed of one or a plurality of concentric circles, even if the frame 200 is sensed diagonally, the image data is the same. It becomes a circular pattern. For this reason, since the recognition program for the circular pattern can be simplified, the memory capacity required for the recognition processing can be reduced, and the processing speed can be increased.

Since the circular patterns 10-A to 10-D are different circular patterns, the cut frame 2
The top, bottom, left, right, front and back of 00 can be determined easily and at high speed.

It should be noted that the circular pattern may have a configuration using a plurality of other concentric circles. In this case, it is necessary to determine what kind of two-dimensional code the two-dimensional code is at the time of cutting out the two-dimensional code by combining four circular patterns. Can be.

(Fourth Embodiment) Next, a computer system according to a fourth embodiment will be described.

The main configuration of the computer system according to the fourth embodiment is the same as the main configuration of the computer system according to the first embodiment, and a description thereof will be omitted. The difference from the first embodiment lies in the two-dimensional code extraction process executed by the CPU in the computer system and the configuration of the extraction pattern described later. Will be described with reference to FIGS.

First, the structure of the two-dimensional code will be described.

FIG. 13 shows a code finding pattern and a cut-out pattern of a two-dimensional code according to the fourth embodiment. In order to avoid confusion with the cutout pattern of the first embodiment, it is referred to as a “center cross cutout pattern”. The central cross cut pattern is a code finding pattern 13 arranged at the center of the two-dimensional code 100.
-1 and the code cutout patterns 13-2 to 13-4 arranged in the up, down, left, and right directions from the code finding pattern 13-1
13-5.

The code discovery pattern 13-1 is
A white circle corresponding to a cell having a diameter of 1 to 2 small cells arranged at the center of the two-dimensional code 100, a black circle surrounding the white circle with a black line corresponding to a cell having a width of 1 small, and the black circle having a width of 1 small It consists of a black circle surrounded by a white line equivalent to a cell.

Also, the code cutting pattern 13-2
Is from the right end of the black circle of the code discovery pattern 13-1.
It consists of a black line for one small cell and a white line for one small cell extending to the right end of the outer frame of the two-dimensional code. Similarly, the code cutting pattern 13-3 is the code finding pattern 1
From the lower end of the black circle of 3-1 to the lower end of the outer frame of the two-dimensional code,
In this configuration, a black line for one small cell width and a white line for one small cell width are drawn, and the code cutout pattern 13-4 is outside the two-dimensional code from the left end of the black circle of the code discovery pattern 13-1. The black line for one small cell and the white line for one small cell are drawn to the left end of the frame.
3-5 is a configuration in which a black line for one small cell and a white line for one small cell are drawn from the upper end of the black circle of the code finding pattern 13-1 to the upper end of the outer frame of the two-dimensional code.

As described above, since the two-dimensional code of the fourth embodiment has the center cross cut pattern inside, the two-dimensional code is easily realized by detecting the center cross cut pattern. can do.

Next, the operation will be described.

A two-dimensional code cutout process executed by the CPU 2 in the computer system according to the fourth embodiment will be described with reference to the flowchart shown in FIG.

First, the CPU 2 retrieves a white circle having a diameter of one small cell or more from the image data of the two-dimensional code including the central cross cut-out pattern (step S141).
Next, it is determined whether or not the periphery of the detected white circle is a black circle (step S142). If not, the process returns to step S141.

Next, if it is a black circle, the CPU 2 detects a black line connected to the circle and stores the address of the black line (step S143). At this time, the stored data is appropriately stored in a memory area in the RAM 3.

Next, the CPU 2 determines the stored black line or the black line stored in the memory area in the RAM 3 as a code cutting pattern, and determines the horizontal or vertical black line address range of the black line. Is determined as the data area of the two-dimensional code, and the two-dimensional code is cut out (step S144).

As described above, the computer system according to the fourth embodiment has the center cross cut pattern inside the two-dimensional code. A two-dimensional code can be cut out from the data.

In the fourth embodiment, one central cross cutout pattern is provided for the two-dimensional code. However, a plurality of central cross-cut patterns may be arranged depending on the size of the two-dimensional code. It is possible to cope with local distortion of the two-dimensional code in each range of the center cross cutout pattern by the code cutout pattern of the center cross cutout pattern.

[0085]

According to the first and seventh aspects of the present invention, the two-dimensional code can be cut out and read for each medium cell constituting the two-dimensional code.
It is not necessary to cut out and read all the two-dimensional codes at once, and furthermore, it is possible to shorten the cutting and reading time by performing a plurality of cutting and reading processes in medium cells in parallel. . In addition, even when the two-dimensional code is distorted, cutting and reading can be performed within a range that does not affect the respective middle cells.

Further, since the data error can be detected in the medium cell unit by the decoding means, the range of the data error can be specified to the range of the medium cell of the two-dimensional code.
The reliability of data error detection can be improved. In addition, since decoding is performed in units of middle cells, the decoding time can be reduced by performing decoding processing on a plurality of read middle cells in parallel.

According to the second aspect of the invention, in addition to the effect of the first aspect, the reading means can cut out the entire two-dimensional code by recognizing the cutout frame pattern. The time for cutting out the dimension code can be reduced. In addition, by using different frame lines for the cut-out frame patterns, the vertical and horizontal directions of the two-dimensional code can be easily recognized.

According to the third aspect of the present invention, in addition to the effect of the first aspect, the reading means recognizes the circular cutout patterns arranged at the four corners of the cutout frame pattern, It is possible to easily recognize the vertical and horizontal directions and the front and back of the cutout frame pattern including the two-dimensional code. In addition, because of the circular shape, the same circular pattern is obtained regardless of the sense from any direction by the area sensor, so that the program for recognizing the circular pattern can be simplified, and the memory capacity required for the recognition process can be reduced. Higher speed can be realized.

According to the fourth aspect of the invention, in addition to the effect of the first aspect, the reading means recognizes the code finding pattern and the cutout pattern, thereby cutting out the entire two-dimensional code. Therefore, the time for cutting out the two-dimensional code can be reduced.

According to the fifth aspect of the present invention, in addition to the effect of the first aspect of the invention, when the reading unit identifies the central pixel of the recognition pointer cell of the middle cell, the reading unit changes the code data up and down. By moving the code data before and after the movement by a predetermined amount in the left and right direction and taking the logical product of the code data before and after the movement, the number of black pixels of the recognition pointer cell is reduced by the white pixels of the separator cells adjacent in the up, down, left and right directions, It is possible to easily and quickly identify the central pixel of the recognition pointer cell.

According to the sixth aspect of the invention, in addition to the effect of the first aspect of the invention, the decoding means further comprises means for determining the value of each code data from the center pixel of each code data constituting the middle cell. Since the determination is made, it is not necessary to determine the value of each code data from a large number of pixels representing each code data, and the determination can be made easily and quickly. Further, since the configuration of each of the middle cells is the same, it is possible to easily and quickly identify the center pixel position of the code data from the center pixel of the recognition pointer cell of the middle cell identified by the reading unit.

[Brief description of the drawings]

FIG. 1 is an exemplary block diagram showing a main configuration of a computer system 1 according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a computer system 1 centering on an area sensor 8 of FIG.

FIG. 3 is a diagram showing a basic configuration of a middle cell 10 according to the first embodiment.

FIG. 4 is a diagram illustrating a data error detection method in the middle cell 10 according to the first embodiment.

FIG. 5 is a diagram showing a two-dimensional code 100 according to the first embodiment.

FIG. 6 is a diagram showing the two-dimensional code 100 surrounded by a frame 150 according to the first embodiment.

FIG. 7 is a flowchart showing a two-dimensional code detection process executed by the computer system 1 according to the first embodiment;

FIG. 8 is a modified example of the frame 150 of the first embodiment.

FIG. 9 is a schematic diagram showing an image in which the area sensor 8 captures the two-dimensional code 100 according to the second embodiment.

FIG. 10 is a diagram showing a circular pattern forming a frame 200 according to the third embodiment;

FIG. 11 is a diagram showing a circular pattern according to the third embodiment.

FIG. 12 is a diagram illustrating a case where a circular pattern according to the third embodiment is sensed obliquely.

FIG. 13 is a diagram showing a code finding pattern and a cutout pattern according to the fourth embodiment;

FIG. 14 is a computer system 1 according to a fourth embodiment.
9 is a flowchart showing a two-dimensional code cutout process executed by (1).

[Explanation of symbols]

Reference Signs List 1 computer system 2 CPU 3 RAM 4 storage device 5 storage medium 6 display unit 7 input unit 8 area sensor 9 bus 10 medium cell PO1 pointer cell S0 to S3 separator cell P0 to P3 parity cell D0 to D15 data cell 10-1, 10 -2, 10-3, 10-4
Medium cells 20, 30, 40, 50, 60, 70, 80, 90,
Medium cell 10-PO1, 20-PO1, 40-PO1, 50-P
O1, pointer cells 10-A, 10-B, 10-C, 10-D Circular pattern for clipping 13-1 Code finding pattern 13-2, 13-3, 13-4, 13-5 Code clipping pattern 100 Two-dimensional code 150, 151-153, 200 Cutting frame

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G06K 19/06 G06K 19/00 E

Claims (7)

[Claims] 1. A two-dimensional code decoding device for reading and decoding a two-dimensional code, wherein the two-dimensional code comprises: an error detection cell for detecting an error in code data expanded in the two-dimensional code; A series of code data including a recognition pointer cell for recognizing the development position of the two-dimensional code is defined as a middle cell, and the plurality of middle cells are arranged as processing units of two-dimensional code data to be decoded. When reading the two-dimensional code, a reading unit that identifies the reading position of each of the medium cells based on the recognition pointer cell and reads the two-dimensional code, and the reading unit that is included in each of the medium cells read by the reading unit. Based on the error detection cell, an error portion in the code data to be decoded for each of the medium cells is detected, and an error portion in the two-dimensional code is detected. Two-dimensional code decoding apparatus being characterized in that and a decoding means for decoding at medium cell units Dodeta. 2. The two-dimensional code further comprises a cutout frame pattern surrounding the expanded plurality of middle cells, wherein the reading means reads the two-dimensional code when reading the two-dimensional code. 2. The two-dimensional code decoding device according to claim 1, wherein the two-dimensional code is cut out and read by recognizing the frame pattern. 3. The two-dimensional code is configured by arranging the cut-out frame pattern, and further arranging a circular cut-out pattern at four corners of the cut-out frame pattern. 2. The two-dimensional code decoding apparatus according to claim 1, wherein, when reading the two-dimensional code, the circular cutting pattern is recognized, and the entire two-dimensional code is cut out and read. 4. The two-dimensional code is configured by arranging a code finding pattern and a cut-out pattern inside the developed middle cells, wherein the reading unit reads the two-dimensional code when reading the two-dimensional code. 2. The two-dimensional code decoding device according to claim 1, wherein the two-dimensional code is cut out and read by recognizing the code finding pattern and the cut-out pattern. 5. The apparatus according to claim 1, wherein said reading means identifies a central pixel of the recognition pointer cell when identifying the recognition pointer cell, and determines the position of the recognition pointer cell from the pixel. 2. The two-dimensional code decoding device according to 1. 6. The decoding means identifies a central pixel position of each code data constituting the middle cell based on a central pixel position of the recognition pointer cell identified by the reading means. 2. The two-dimensional code decoding device according to claim 1, wherein the value of each of the code data is determined from the identification result of the above. 7. A storage medium storing a computer-executable program for reading and decoding a two-dimensional code, wherein the two-dimensional code detects an error in code data expanded in the two-dimensional code. A series of code data including an error detection cell for causing the two-dimensional code to be recognized and a recognition pointer cell for recognizing the developed position of the two-dimensional code is defined as a middle cell. When reading this two-dimensional code, a computer-executable program code for identifying the read position of each of the middle cells based on the recognition pointer cell and reading the two-dimensional code is provided. Based on the read error detecting cells included in each of the read middle cells, Detects the error location in Dodeta, storage medium characterized by computer for decoding the code data of the in the two-dimensional code in the middle cell unit and program code executable, storing a program including.