JP6261118B2 - Two-dimensional code reading method and recording medium for the two-dimensional code - Google Patents

Description

  The present invention relates to a two-dimensional code reading method for reading a two-dimensional code from a two-dimensional code image captured by an image input device such as an image sensor and a camera, and a recording medium for the two-dimensional code.

  Since the two-dimensional code was invented in the United States in the 1980s, a two-dimensional code and a two-dimensional code reading method that can record a large amount of data and have high reading accuracy have been disclosed (for example, (See Patent Document 1). Binary data is converted into cells, and the cells are arranged in two vertical and horizontal directions. The data element area is configured in a two-dimensional matrix, a rectangular part consisting of a broken line surrounding the data element area, and a broken line that forms the rectangular part. And a T-shaped marker for data recognition for cutting out a data element area and cutting out an image formed in a T-shape with broken line segments and a heading line. A two-dimensional code reading method capable of obtaining information recorded in a data element region by reading a two-dimensional code having the number of broken line segments, and is a first method for acquiring image data of a two-dimensional code. A step, a second step of detecting a T-shaped continuous pixel region from the image data acquired in the first step, and a T-shape detected in the second step. A third step of determining whether or not the continued pixel region is a T-shaped marker for data recognition, and a T-shaped continuous pixel region determined as a T-shaped marker for data recognition in the third step. A fourth step for determining whether or not the number has reached a predetermined minimum number at which a data element region can be cut out and an image can be cut out; If it is determined that the predetermined minimum number has been reached, a cell array of data element regions is detected using a T-shaped continuous pixel region group determined as a T-shaped marker for data recognition. And a sixth step of acquiring information from the data element region based on the cell array of the data element region detected in the fifth step.

According to the two-dimensional code reading method according to the first aspect as described above, it is only necessary to detect a continuous T-shaped pixel region as image data and compare the shape with a standard T-shaped marker for data recognition. Since it is possible to detect a plurality of T-shaped continuous pixel region groups arranged around the data element region in accordance with the segmentation and image segmentation, more than 4 cells around the two-dimensional code It is possible to improve the recognition rate of the two-dimensional code by the two-dimensional code reader without securing the white margin.

JP 2011-70477 A

However, the above-described image recognition method includes a first step of acquiring image data of a two-dimensional code, and a second step of detecting T-shaped continuous pixel regions from the image data acquired in the first step. A third step for determining whether the T-shaped continuous pixel region detected in the second step is a T-shaped marker for data recognition, and a T-shaped marker for data recognition in the third step A fourth step of determining whether or not the number of determined T-shaped continuous pixel regions has reached a predetermined minimum number at which a data element region can be cut out and an image can be cut out; If it is determined that the predetermined minimum number that can be cut out and cut out in step 4 has been reached, the T-shapes determined to be data recognition T-shaped markers are consecutive. A fifth step of detecting a cell array of the data element region using the pixel region group, and a sixth step of acquiring information from the data element region based on the cell array of the data element region detected in the fifth step Steps are required, and there are many steps until image recognition, and it takes a lot of time to cut out images.

In addition, the above attempt follows the conventional image segmentation algorithm, that is, an image segmentation method in which an image of a two-dimensional code is captured and binarized to find and recognize a T-shaped marker for data recognition. However, there is a drawback that it takes time to cut out an image.

However, due to the remarkable technological innovation in recent years, the reading accuracy has been dramatically increased by increasing the pixel count of the image scanner and increasing the CPU processing speed. The meaning to do is fading.

An object of the present invention is to provide quick symbol recognition and a large capacity two-dimensional code, which are considered incompatible with such a conventional two-dimensional code.

In order to achieve the above-mentioned object, the two-dimensional code of the present invention uses a conventional two-dimensional code to make a symbol for image clipping conspicuous, or a large number of T-shaped markers in a matrix data element part (MDA). ) And the shape of the matrix data area narrowed, and the image cutout is limited to only four image cutout symbols at four corners having different shapes. The line segment is provided on four sides, and the scanning guideline is arranged on the inner side from the square bracket line segment toward the matrix data part (MDA), thereby increasing the image cut-out and recognition speed of the two-dimensional code.

In addition, the conventional image printing configuration cell has a configuration of 4 dots per cell, and in the data matrix area (MDA), it overlaps depending on the paper quality on which adjacent cells are printed and the status of the printing machine, and is used for data recognition. Since there is a defect that the T-shaped marker image is cut out, the print configuration of the present invention is set to 3 dots or less per cell to prevent overlapping of cells, thereby increasing the information amount and the recognition speed. It provides a two-dimensional code that can be accelerated.

According to the present invention, four image segmentation symbols having different shapes are arranged at the four corners of the two-dimensional matrix data element region, and the pattern feature recognition process is executed. If there is a feature figure, it takes time to recognize, so by making the cell configuration of the MDA area less than 3 dots per cell, it is possible to immediately recognize the 4 symbols for image cropping, and position information and Rotation information can be acquired.

In addition, four square bracket-shaped distortion correction symbols are arranged at the top of the four sides of the MDA, and a scanning guideline is provided inward from the square bracket-shaped distortion correction symbol toward the MDA. Since they can be formed vertically, it is possible to provide a two-dimensional code that can be efficiently used for execution of error correction processing and compression processing.

It is the schematic which shows one Embodiment of the two-dimensional code concerning this invention. It is a figure which shows one form of the image cutout pattern of the two-dimensional code of this invention. It is a figure which shows one form of the distortion correction pattern of the two-dimensional code of this invention, and a scanning guideline. It is a figure which shows one form of the data block line of the two-dimensional code of this invention. It is a flowchart figure which shows the example of preferable embodiment by the two-dimensional code reading method of this invention.

  The best mode for carrying out the two-dimensional code reading method and the two-dimensional code recording medium of the present invention will be described below with reference to the drawings.

  Embodiment of Two-Dimensional Code FIG. 1 is a schematic diagram showing an embodiment of a two-dimensional code according to the present invention. As shown in the figure, the two-dimensional code 1 according to the present embodiment includes a matrix data portion (MDA) in which binarized data is stored in the form of light and dark square cells, and four corners of the matrix data portion (MDA). 4 types of image cutout patterns, four square brackets arranged so as to surround the MDA, and each side K1, K2, K3, K4 of the square brackets toward the matrix data part 2 respectively Scanning lines (projections) K10 to K17, K20 to K27, K30 to K37, and K40 to K47 with solid lines extending vertically are provided.

  FIG. 2 shows one form of the image cut-out pattern, and A arranged at the upper left corner of the matrix data part (MDA) makes the length of one side equal to the length of each scanning line. It is a square and is painted black. B arranged horizontally in the upper right corner of the matrix data part (MDA) is a rectangle whose left and right short sides are equal to the length of each scanning line, and the inner right end of this rectangle has a length of one side. A square with a length equal to the length of each scanning line is placed, and this square is filled with black. C arranged in the lower right corner of the matrix data portion (MDA) is an inverted L shape in which the length equal to the length of each scanning line is blacked out as the width of the lower left portion of the inverted L shape and the short side of the upper right portion. It is. D arranged vertically in the lower left corner of the matrix data part (MDA) is a vertically long rectangle whose upper and lower short sides are equal to the length of each scanning line. A square with the length of one side equal to the length of each scanning line is arranged, and this square is filled with black.

Shown in FIG. 3 are K1, K2, K3, and K4 in the shape of square brackets, each having square projections, inwardly facing the matrix data portion (MDA), K1 and K3, K2 and K4 are arranged to face each other, and scanning guidelines K10 to K47 are arranged at regular intervals corresponding to the data amount of the matrix data portion.

The cell arrangement of the data element area MDA is detected by scanning guidelines K10, K11, K12, K13, K15, K16 extending vertically inward from the square bracket-shaped line segments K1, K2, K3, K4 in the MDA direction. K17, K20, K21, K22, K23, K24, K25, K26, K27, K30, K31, K32, K33, K34, K35, K36, K37, K40, K41, K42, K43, K44, K45, K46, K47 Can scan the data element area MDA. For example, the data block line can be obtained by connecting the scanning guidelines K40 and K20. If either one of the scanning guidelines exists, the data block line is obtained by obtaining a line parallel to K1 or K3. be able to. Accordingly, the data block line connecting the scanning guidelines K43 and K23 and the data block line connecting the scanning guidelines K46 and K26 are also determined to be parallel to K1 or K3 if either one of the heading lines exists. Thus, this data block line can be obtained. In addition, the data block line connecting the scanning guidelines K11 and K31 and the data block line connecting the scanning guidelines K17 and K37 can be obtained by obtaining a line parallel to K2 and K4, respectively, if any one of the scanning guidelines exists. This data block line is required.

  The number of scanning guidelines is determined independently in each of the horizontal direction (X-axis direction) and the vertical direction (Y-axis direction) according to the number of data in the data element area MDA. MDA) capacity can be determined.

  It is possible to restore the original data by equally dividing the data cell in the data element area MDA by scanning guidelines to obtain the position coordinates, and by sampling the binary value of each data cell to obtain bit string data. it can. If an error correction code is added to the bit string data of the two-dimensional code, error correction is performed.

  As described above, according to the two-dimensional code of the present invention, symbols having different shapes provided at the four corners of the matrix data portion (MDA) are detected as image cut-out patterns from the grayscale image, and thus two conventional codes are used. Even without performing the digitization work, it is possible to increase the recognition speed of the image and improve the recognition rate of the two-dimensional code by the two-dimensional code reader.

  Note that a data processing procedure as shown in the flowchart of FIG. 5 may be performed.

  In this data processing procedure, as shown in FIG. 2, a gray scale image is taken by an image scanner, and the four image-cutting symbols having different shapes are recognized as shown in FIG. Then, it is determined whether or not the pattern shape is stored in advance or within a predetermined error range. In the conventional two-dimensional code, the cell configuration for printing is a 4-dot configuration for each cell. However, the cells overlap each other depending on the quality of the printing machine or paper to be printed, and it takes time to recognize the data area. Since the cell data setting cell configuration of the matrix data part (MDA) is set to 3 dots or less per cell so that the cells do not overlap each other, the symbol for image clipping is recognized. Is easily possible.

Subsequently, the four-sided square bracket-shaped distortion correction pattern shown in FIG. 3 is recognized, the image angle of the two-dimensional code is adjusted, and the image is cut out.

Subsequently, as shown in FIG. 4, the data block lines are formed by sequentially connecting the opposing lines on the scanning guide line recognized by the two parallel sides of the square.

Furthermore, the value of each cell is sampled and used as bit string data.
Since the error correction code is added to the bit string data of the two-dimensional code in advance, error correction is performed using this, and finally compression processing is performed.

As described above, according to the two-dimensional code reading method of the present embodiment, it is possible to quickly cut out an image by feature pattern recognition image processing of four image cut-out symbols having different shapes, and to easily capture data. It can be carried out.

A program in which such a data processing procedure is executed by the control unit of the two-dimensional code reader is recorded on a computer-readable recording medium such as a CD or DVD, so that a plurality of two-dimensional code readers or computers are recorded. Available at

Although the present invention has been described with the specific embodiments shown in the drawings, the present invention is not limited to the embodiments shown in the drawings, and is known so far as long as the effects of the present invention are achieved. It goes without saying that any configuration can be adopted.

A ・ ・ ・ ・ Image clipping symbol placed in the upper left corner
B ··· Image clipping symbol placed horizontally in the upper right corner
C ・ ・ ・ ・ Reverse L-shaped image cutout symbol placed in the lower right corner
D ・ ・ ・ ・ Rectangular image cut out symbol placed vertically in the lower left corner
K1 ··· A square bracket-shaped distortion correction line placed between A and B image cutout symbols
K2 ... A square bracket-shaped distortion correction line placed between the B and C image cutout symbols.
K3 ······ Bracket-shaped distortion correction line placed between C and D image cutout symbols
K4 ··· Square bracket-shaped distortion correction line placed between A and D image cutout symbols
K10, K11, K12, K13, K14, K15, K16, K17 ・ ・ ・ Scanning guideline extending vertically inward from the line K1 toward the MDA
K20, K21, K22, K23, K24, K25, K26, K27 ・ ・ ・ Scanning guideline extending vertically inward from the line segment K2 in the MDA direction
K30, K31, K32, K33, K34, K35, K36, K37 ・ ・ ・ Scanning guideline extending vertically inward from the line K3 in the MDA direction
K40, K41, K42, K43, K44, K45, K46, K47 ・ ・ ・ Scanning guideline extending vertically inward from the line segment of K4 in the MDA direction
MDA ・ ・ ・ ・ Matrix data section

Claims (2)

A matrix data portion (MDA) in which binary data is symbolized in a cell shape to form a two-dimensional matrix, and image cutout patterns A having different shapes at the four corners of the first matrix data portion (MDA), B, C, D are provided, and four square brackets having protrusions inward toward the MDA portion are provided between the image cutout patterns at the four corners, and from the inside of the square brackets toward the MDA portion. It has a number of scanning guidelines (protrusions) with a solid line extending vertically ,
The shape of the image cutout pattern provided at the four corners of the matrix data part (MDA) is a square in which the pattern A arranged at the upper left corner is equal in length to one side of each scanning guideline. Pattern B, which is painted black and placed horizontally in the upper right corner, is a rectangle whose left and right short sides are equal to the length of each scanning guideline. A square having a length equal to the length of each scanning guideline is arranged, and this square is filled with black. Inverted L-shaped, painted black as the width of the short side at the lower left and upper right, and the pattern D arranged vertically at the lower left corner is the upper and lower short sides The length is a rectangle equal to the length of each scanning guidelines on the inner lower end of the rectangle, placing a square of equal length of one side and the length of each scanning guidelines have the square blacked out Rukoto Two-dimensional code characterized by In the feature recognition of the image cut-out patterns A, B, C, and D, if the same type of pattern exists in the two-dimensional code, the feature recognition is delayed and the feature recognition is delayed. 2. The two-dimensional code according to claim 1, wherein the structure of one cell is set to 3 dots or less to prevent the cells from being combined during printing and to prevent the generation of the same type of pattern .