JP2007047871A - Bar code reader and bar code reading method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bar code reader and a bar code reading method capable of accurately acquiring information shown by a bar code colored in three or more colors regardless of a display state. <P>SOLUTION: The bar code reader 1 is a device for acquiring information shown by the bar code colored in three or more colors by reading the bar code. The bar code reader 1 comprises, as functional components, a data reading part 11 reading an area including the bar code and the peripheral part thereof to acquire read data; a data separation part 12 separating bar code data and reference data from the read data and performing color decomposition; a reference information storage part 13; a reference information comparison part 14; a correction value storage part 15; a color information correction part 16 correcting the bar code data based on the reference data; a used color information storage part 18; a color information specification part 17; and an information acquisition part 19 acquiring information shown by a bar code part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a barcode reading apparatus and a barcode reading method.

A bar code is a symbol obtained by coding information, and is applied to various fields such as mobile phones, physical distribution, and information media. In order to further promote the application in such various fields, it is required to further increase the capacity of information held by the barcode. In order to meet such demands, it has been recently studied to apply barcodes color-coded to three or more colors (see, for example, Patent Documents 1 and 2). A barcode that is color-coded into three or more colors can contain more information than a black and white barcode.
JP 2000-244857 A JP 2003-122876 A

  However, barcodes classified into three or more colors may be printed in a color different from the color originally indicating the information. In that case, there arises a problem that the information to be indicated by the barcode cannot be acquired correctly.

  The present invention has been made to solve the above-described problems, and a barcode reader that can accurately acquire information indicated by a barcode that is color-coded in three or more colors regardless of the display state. An object is to provide a barcode reading method.

  In order to achieve such an object, a barcode reading apparatus according to the present invention is a barcode reading apparatus that reads a barcode that is color-coded into at least three colors and acquires information indicated by the barcode, Data reading means for reading an area including a barcode and its peripheral portion and acquiring read data for specifying a color at a position in the area, and barcode data corresponding to the barcode and a reference from the acquired read data Data separation means for separating data, color information correction means for correcting color information of each of a plurality of data elements constituting the barcode data based on the separated reference data, and correction by the color information correction means The barcode data and the reference data are configured for the color information of each of the plurality of data elements constituting the barcode data. A color information specifying unit that specifies color information that can be used as possible color information; and an information acquisition unit that acquires information indicated by the barcode based on a result of specifying the color information specifying unit. .

  On the other hand, the barcode reading method according to the present invention is a barcode reading method for obtaining information indicated by the barcode by reading the barcode classified into at least three colors, and includes the barcode and its peripheral portion. A data reading step for reading a region and acquiring read data for specifying a color at a position in the region, and a data separation step for separating barcode data corresponding to a barcode and reference data from the acquired read data And a color information correction step for correcting color information of each of a plurality of data elements constituting the barcode data based on the separated reference data, and barcode data in which the color information is corrected in the color information correction step Included in barcode data and reference data for color information for each of multiple data elements A color information specifying step of specifying a color information available as the color information that, based on the identification result of the color information specifying step, characterized in that it comprises an information acquisition step of acquiring information indicating the barcode, a.

  According to these bar code reading devices and bar code reading methods, it is possible to read bar codes color-coded in at least three colors or more, and to read bar codes containing a large amount of information. In these bar code reading devices and bar code reading methods, the color information of each of a plurality of data elements constituting the bar code data is specified based on reference data separated from the read data. Further, the information indicated by the barcode is acquired based on the result of specifying the color information in this way. Therefore, according to these bar code reading devices and bar code reading methods, it is possible to accurately acquire information indicated by bar codes that are color-coded at least in three colors regardless of the display state.

  The data separation means arranges primary color components corresponding to the primary color components obtained by separating all the colors that can be included in the barcode and are arranged in a predetermined order at predetermined positions corresponding to the barcode. It is preferable to obtain the reference data by separating the read data included. In this case, since the reference data is at a predetermined position of the read data, separation from the barcode data is easy. In addition, since the reference data includes all primary colors that can form a barcode, it is possible to accurately specify color information based on the reference data by adding and mixing the primary colors. In order to specify color information with high accuracy, characteristic colors such as black and white can be used as the color applied to the reference data, and the reference data can be used to detect the orientation and inclination of the barcode. .

  For example, the color information correction unit may be configured such that, for example, a primary color component obtained by decomposing color information included in the reference data and a primary color component obtained by decomposing color information of each of a plurality of data elements constituting the barcode data in advance. The color information of each of a plurality of data elements constituting the barcode data may be corrected by performing correction based on a difference obtained by comparing the prepared comparative primary color component.

  The information acquisition means, for example, converts each value representing the lightness of each primary color component of the color information identified as usable by the color information identification means from the barcode data corrected by the color information correction means into a binary bit string. For the converted bit string, the information indicated by the barcode may be acquired by decoding the code added at the time of printing.

  As described above, according to the barcode reading apparatus and the barcode reading method according to the present invention, the information indicated by the barcode classified into three or more colors can be accurately acquired regardless of the display state.

  The knowledge of the present invention can be easily understood by considering the following detailed description with reference to the accompanying drawings shown for illustration only. Subsequently, embodiments of the present invention will be described with reference to the accompanying drawings. Where possible, the same parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a diagram for explaining a configuration of an embodiment of a barcode reading apparatus configured according to the present invention. The configuration of the barcode reader 1 will be described with reference to FIG. The bar code reader 1 is physically a computer system having an input interface such as a CPU, a memory, and a scanner. The barcode reader 1 includes, as functional components, a data reading unit (data reading unit) 11, a data separation unit (data separation unit) 12, a reference information storage unit 13, a reference information comparison unit 14, and a correction value storage unit. 15, a color information correction unit (color information correction unit) 16, a color information identification unit 17 (color information identification unit), a use color information storage unit 18, and an information acquisition unit (information acquisition unit) 19.

  Prior to detailed description of each element of the barcode reader 1, a reading area that the barcode reader 1 reads will be described. FIG. 2 is a diagram schematically illustrating a reading area 20 read by the barcode reading apparatus 1 according to the present embodiment. The reading area 20 includes an area including a reference information part 30, a barcode part 40, and a margin part 21. The reference information unit 30 and the barcode unit 40 are two-dimensional barcodes, and the reference information unit 30 is divided into five minute portions 31 to 35. In the minute portions 31 to 35, a specific color is displayed as necessary in addition to the primary colors constituting all the colors displayed on the barcode unit 40. The barcode part 40 is divided into 20 minute parts 41 to 60, and is color-coded into at least three colors. In FIG. 2, the difference of the color given to each micro part 31-60 by the difference in the shade of shaded line, thickness, and a pattern is represented. Moreover, in FIG. 2, the code | symbol of the micro parts 42-44, 47-49, 52-54 is abbreviate | omitted for easiness to see.

  The blank portion 21 has a closed shape surrounding the reference information portion 30 and the barcode portion 40. The margin portion 21 is provided with a color that is not included in the use color data stored in the later-described use color information storage unit 18 as usable color information.

  The reference information unit 30 displays the primary colors of all the colors that can constitute the barcode unit 40, and in the peripheral portion of the barcode unit 40, along one side of the barcode unit 40 in the present embodiment, It is configured by arranging these colors. Therefore, for example, when the barcode part 40 is color-coded according to 256 gradations of each color expressed in RGB, the reference information part 30 is R color for the first color part, G color for the second color part, and G color for the third color part. B color is displayed adjacent to the barcode portion 40.

  Returning to FIG. 1 again, each component of the barcode reader 1 will be described in detail. The data reading unit 11 is a part that reads the reading area 20 that is an area including the reference information part 30, the barcode part 40, and the margin part 21 and acquires read data. In the read data, the color at the position in the reading area 20 is specified. The data reading unit 11 outputs the read data to the data separation unit 12. The data reading unit 11 is physically a scanner or the like.

  The data separation unit 12 is a part that separates the reference data corresponding to the reference information unit 30 and the barcode data corresponding to the barcode unit 40 from the read data. When the data separation unit 12 receives the read data from the data reading unit 11, the data separation unit 12 color-separates the color information of the reference data separated from the read data into primary color components, and the reference primary color data including the obtained primary color components is a reference information comparison unit 14, and the barcode primary color data including the primary color components obtained by color-separating the color information of the barcode data separated from the read data is output to the color information correction unit 16.

  The data separation unit 12 separates read data corresponding to a portion including a portion applied to all primary colors that can constitute the barcode unit 40 at a predetermined position corresponding to the barcode unit 40. To obtain the reference data. In the reading area 20 that is read by the barcode reading apparatus 1 according to the present embodiment, the reference information section 30 has a predetermined reference information color at a predetermined position adjacent to the barcode section 40 in the reading area 20. Are arranged in order. That is, the data separation unit 12 is arranged in a predetermined order at a predetermined position corresponding to the barcode unit 40, and is a primary color obtained by separating all the colors that can constitute the barcode unit 40. The reference data is obtained by separating the read data including the primary color components corresponding to the components.

  The reference information storage unit 13 is a part that stores comparative primary color data including primary color components of colors applied to a preset reference information unit 30. The comparative primary color data is used as a reference for detecting the degree of color shift caused by printing or the like for the reference primary color data obtained from the reference data separated from the read data. The reference information storage unit 13 outputs comparative primary color data to the reference information comparison unit 14 as necessary.

  The reference information comparison unit 14 compares the comparison primary color data output from the reference information storage unit 13 with the reference primary color data output from the data separation unit 12, and the color shift for each primary color component included in the color information of the reference data. This is a part for calculating a correction value. When the reference information comparison unit 14 receives the reference primary color data from the data separation unit 12 and the comparison primary color data from the reference information storage unit 13, it calculates a color misregistration correction value and outputs it to the correction value storage unit 15. The calculated color misregistration correction value is stored in the correction value storage unit 15 for use in correcting the barcode data.

  The correction value storage unit 15 is a part for storing the color misregistration correction value calculated by the reference information comparison unit 14. The correction value storage unit 15 outputs an offset correction value to the color information correction unit 16 as necessary.

  The color information correction unit 16 is a part for correcting the color information of each of a plurality of data elements constituting the barcode data based on the reference data separated from the read data. The color information correction unit 16 adds the color misregistration correction value stored in the correction value storage unit 15 to the portion corresponding to the primary color of the barcode primary color data to the barcode primary color data output from the data separation unit 12. As a result, the color information of the barcode data is corrected to obtain corrected barcode data. As a result, the color information of the barcode data that has been shifted due to the printing condition or the like is reproduced.

  A color correction method for barcode data in the barcode reader 1 will be specifically described. 3 to 5 are diagrams for explaining an example of a color correction method in the case of RGB notation. 3 to 5, the horizontal axis represents wavelength, and the vertical axis represents amplitude intensity.

A color shift that deviates from the colors originally applied to the reference information section 30 and the barcode section 40 due to printing or the like is a wavelength shift of the primary colors constituting the colors applied to the reference information section 30 and the barcode section 40. And a shift in the mixing amount of the primary colors constituting the color. FIG. 3 is a diagram for explaining the occurrence of color misregistration. The graph X ₀ shown in FIG. 3 is blue data before printing, the graph Y ₀ is green data before printing, the graph Z ₀ is red data before printing, and the graph X ₁ is blue data at the time of reading. Graph Y ₁ represents green data at the time of reading, and graph Z ₁ represents red data at the time of reading.

As shown in FIG. 3, reading the printed reading area 20 causes wavelength shifts Δλ ₁ , Δλ ₂ , Δλ ₃ , and amplitude intensity shifts ΔA ₁ , ΔA ₂ , ΔA ₃ for each primary color, This causes color misregistration. In order to correct the color misregistration generated in this way, the barcode reader 1 performs wavelength / amplitude intensity conversion on the color information applied to the reference information unit 30 and the barcode unit 40 in the data separation unit 12 by Fourier transform, A primary color component constituting the color is taken out, and a shift in wavelength and a shift in amplitude intensity are detected.

FIG. 4 is a diagram for explaining a method of calculating the color misregistration correction value by comparing the reference primary color data and the comparative primary color data. Blue data graph X ₂ is a comparative primary color data shown in FIG. 4, a graph Y ₂ is a green data comparison primary data, red data graph Z ₂ are comparative primary color data, the graph X ₃ blue data of the reference primary color data The graph Y ₃ represents the green data of the reference primary color data, and the graph Z ₃ represents the red data of the reference primary color data.

The reference information comparison unit 14 compares the comparison primary color data stored in the reference information storage unit 13 with the reference primary color data output from the data separation unit 12, as shown in FIG. Wavelength shifts Δλ ₄ , Δλ ₅ , Δλ ₆ and amplitude intensity shifts ΔA ₄ , ΔA ₅ , ΔA ₆ , which are color shift correction values, are calculated and stored in the correction value storage unit 15. As described above, the comparison primary color data stored in the reference information storage unit 13 is preset with the wavelength and amplitude intensity of the primary color component for each color information of the reference data.

FIG. 5 is a diagram for explaining correction of color information of barcode data. The graph X ₄ shown in FIG. 5 is blue data corrected by the color shift correction value, the graph Y ₄ is green data corrected by the color shift correction value, and the graph Z ₄ is red data corrected by the color shift correction value. and the blue data of the bar code data before the graph X ₅ is corrected, the green data of the bar code data before the graph Y ₅ is corrected, the graph Z ₅ represents respectively a red data bar code data before correction.

The color information correction unit 16 calls the color misregistration correction value from the correction value storage unit 15 and, as shown in FIG. 5, calls the color misregistration correction values (wavelength shifts Δλ ₇ , Δλ ₈ , Δλ ₉ , and amplitude intensity). The deviations ΔA ₇ , ΔA ₈ , ΔA ₉ ) are added to or subtracted from the barcode primary color data output from the data separator 12 for each primary color. As a result, the color information of the barcode data that has been shifted due to printing or the like is reproduced as the color information before printing or the like, and the original color information that is the original color information is reproduced.

  As described above, the color information correction unit 16 converts the color information included in the reference data into the primary color component (barcode primary color data) obtained by decomposing the color information of each of the plurality of data elements constituting the barcode data. By performing correction based on the difference (color misregistration correction value) obtained by comparing the primary color component (reference primary color data) obtained by the separation and the comparison primary color component (comparative primary color data) prepared in advance, the barcode The color information of each of a plurality of data elements constituting the data is corrected.

  The color information specifying unit 17 can be used as color information included in the barcode data and the reference data for the color information of each of a plurality of data elements constituting the barcode data whose color information has been corrected by the color information correction unit 16. This is the part that specifies the correct color information. The color information specifying unit 17 compares the corrected barcode data, which is the barcode data corrected by the color information correction unit 16, with the use color data stored in the use color information storage unit 18. In the use color data, color information of colors that can be used as colors that can be applied to the barcode unit 40 is set in advance. The color information specifying unit 17 obtains specific correction barcode data including a part corresponding to color information determined to be usable as a color that can be applied to the barcode unit 40 of the corrected barcode data as a result of comparison. 19 output. A color that is not used as a color that can be applied to the barcode portion 40 can be used for the margin portion 21 of the reading region 20 or a headline in the barcode. The determination that the color can be used as a color that can be applied to the barcode unit 40 is made when the strength of the correction barcode data matches the strength of the usage color data.

  The information acquisition unit 19 is a part that acquires digital information indicated by the barcode unit 40 based on the specific correction barcode data output from the color information specifying unit 17. The information acquisition unit 19 has a function of reversely converting encoding such as data compression and error correction performed at the printing source and combining the original digital information.

  FIG. 6 is a diagram schematically showing the bit structure of the specific correction barcode data. The vertical axis in FIG. 6 corresponds to the vertical direction of the reference information unit 30 and the barcode unit 40 that are two-dimensional barcodes, and the horizontal axis corresponds to the horizontal direction of the reference information unit 30 and the barcode unit 40 that are two-dimensional barcodes. Correspond. The depth direction in FIG. 6 corresponds to a bit string (length n) representing color information applied to each minute portion 31-60. Therefore, each bit string in FIG. 6 corresponds to each minute portion 31 to 60 of the reference information portion 30 and the barcode portion 40.

  The length n of the bit string differs depending on the number of color gradations used for color coding of the reference information unit 30 and the barcode unit 40. That is, for example, when color classification is performed according to 256 gradations of each color, each bit string is 24 bits, and the surface constituted by each bit of the bit string representing the color is from the first surface to the 24th surface. Therefore, each minute portion 31 to 60 reproduces the color by the arrangement of the first bit Xa to the nth bit Xn (X = 31 to 60).

  A specific example of obtaining information indicated by a barcode that is color-coded into three or more colors will be described. When information is recorded in each surface unit of the barcode data and the reference data, bits 31a to 60a constituting the first surface, bits 31b to 60b constituting the second surface, bits 31n constituting the nth surface By arranging the data values stored in the respective bits in the order of ˜60n, the information indicated by the reference information unit 30 and the information indicated by the barcode unit 40 can be acquired.

  Alternatively, when information is recorded in units of bit strings representing the color of the reference information and the barcode data, the first to nth bits 31a to 31n of the minute portion 31 and the first to nth bits 32a to 32n of the minute portion 32 are recorded. ..., the information of the reference information unit 30 and the information indicated by the barcode unit 40 are obtained by arranging the data values stored in the respective bits in the arrangement of the first to nth bits 60a to 60n of the minute portion 39. can do.

  Next, a barcode reading method by the barcode reading apparatus 1 will be described while explaining specific operations of the barcode reading apparatus 1 with reference to a flowchart shown in FIG.

  First, the data reading unit 11 of the barcode reading apparatus 1 reads the reading area 20 and acquires electrical reading data (data reading step S1).

  The data separation unit 12 to which the read data is input separates the barcode data and the reference data and obtains them from the read data (data separation step S2). In separating the reference data, the data separating unit 12 separates the reference data arranged at a predetermined position in a predetermined order. The reference data and barcode data obtained by separation are each color-separated into primary color components by Fourier transform in the data separation unit 12 to obtain barcode source color data and reference primary color data. The reference primary color data is output to the reference information comparison unit 14, and the barcode primary color data is output from the color information correction unit 16 (data separation step S2).

  The reference information comparison unit 14 compares the reference primary color data output from the data separation unit 12 with the comparison primary color data stored in the reference information storage unit 13, and determines the color for each primary color component included in the color information of the reference data. A shift correction value is calculated (color shift correction value calculation step S3). The reference information comparison unit 14 stores the color misregistration correction value thus calculated in the correction value storage unit 15 (correction value storage step S4).

  The color information correction unit 16 compares and references the bar code primary color data output from the data separation unit 12 and the color misregistration correction value stored in the correction value storage unit 15 to perform color misregistration correction of each primary color component. Then, the color information of the barcode data is corrected, and the corrected barcode data is output to the color information specifying unit 17. As a result, the color information of the barcode data shifted due to printing or the like is reproduced as the original color information (color shift correction step S5). The color misregistration correction value calculation step S3, the correction value storage step S4, and the color misregistration correction step S5 constitute a color information correction step.

  The color information specifying unit 17 to which the correction barcode data is input refers to the use color data read from the use color information storage unit 18 storing the primary color component information of the color information that can be used in advance, and uses the correction barcode data. A portion (specific correction barcode data) corresponding to the color information set in the color data is output to the information acquisition unit 19. The color information specifying unit 17 discards the portion of the correction barcode data that does not correspond to the color information set in the use color data without outputting it to the information acquiring unit 19 (color information specifying step S6).

  The information acquisition unit 19 converts the value for each primary color component of the specific correction barcode data output from the color information specifying unit into a binary number, and decodes it from various code processing and conversion such as error correction performed at the printing source. Thus, the information indicated by the barcode unit 40 is restored (information acquisition step S7). More specifically, the information acquisition unit 19 performs reverse conversion such as zero bit string compression or addition of an error correction code applied to the binary number converted from the value for each primary color component of the specific correction barcode data. And decode it into the information bit string of the printing source.

  According to the barcode reading apparatus 1, as described above, the reference information portion 30 and the barcode portion 40 that are color-coded into at least three colors can be accurately read, so that a barcode including a large amount of information is read. It becomes possible.

  In particular, the bar code reader 1 does not correspond to predetermined information for each color, but generates an information bit string from the displayed color, so that it can cope with a bar code having an increased storage capacity. it can.

  In the barcode reading apparatus 1, the color information of each of the plurality of data elements constituting the barcode data is specified by the color information correction unit 16 and the color information specifying unit 17 by the correction value based on the reference data separated from the read data. ing. Further, based on the result of specifying the color information in this way, information indicated by the barcode unit 40 is acquired by the information acquisition unit 19. Therefore, according to the barcode reading apparatus 1, it is possible to accurately acquire information indicated by a barcode that is color-coded at least three colors regardless of the display state that changes depending on the printing conditions.

  The data separating unit 12 separates the reference information unit 30 disposed at a predetermined position with respect to the barcode unit 40 from the read data. Therefore, it is possible to easily separate the reference data and the barcode data. It is preferable that the predetermined arrangement position of the reference information unit 30 is automatically determined by the shape and size of the barcode.

  Further, in the data separation unit 12, each of the reference data and the barcode data is color-separated into primary colors constituting all displayed colors, and the reference primary color data and the barcode primary color data are obtained. Since the color information is corrected based on these primary color data, the information included in the reference information portion can be corrected with a high degree of accuracy, and the color information of the color originally applied to the barcode portion 40 can be corrected. It can be easily reproduced.

  The color information specifying unit 17 refers to use color data stored in advance in the use color information storage unit 18 and includes a portion including color information that can be used as a color that can be applied to the barcode unit 40 in the corrected barcode data. Separate no parts. Therefore, the color information of the margin part 21 or the color information such as the heading or the symbol representing the content indicated by the barcode part 40 can be easily changed for the part not including usable color information. In this way, by setting available colors in advance, flexible bar codes can be used, and convenience in bar code use can be improved.

  The smallest unit of bar code data is 1 pixel, which can be miniaturized. For this reason, the bar code can have an arbitrary shape such as a character shape in addition to a basic shape such as a square or a circle.

  In addition, a barcode that is color-coded into three or more colors can include a lot of information. For this reason, the use of the barcode reader 1 that reads barcodes classified into three or more colors makes it possible to save resources on the storage medium.

  The correction based on the reference data of the barcode data is performed based on the barcode primary color data including the primary color components and the reference primary color data. Therefore, even if the number of colors applied to the reference information unit 30 is small, highly accurate correction can be performed. This facilitates the setting of the position where the reference information unit 30 is arranged in advance, and various arrangement methods such as mixing reference information in the barcode unit 40 or using the barcode unit as the reference information unit are possible. is there.

  The barcode read by the barcode reading method according to the present embodiment is not limited to a two-dimensional barcode. Furthermore, the color of the margin part may be a color given to the barcode. Further, the method for specifying the color information of each of the plurality of data elements constituting the barcode data based on the reference data and the method for acquiring the information indicated by the barcode are not limited to the examples described above.

  Moreover, it is preferable that the barcode reader further includes an error correction unit that detects and corrects dirty data with respect to the barcode data corrected by the information acquisition unit. By further including an error correction unit, it is possible to reliably read even a slight stain on the barcode.

  Further, authentication can be realized by using the barcode reading apparatus and barcode reading method according to the present invention. The authentication is realized by obtaining information (bit string) from the color-coded authentication barcode and applying the bit string to a designated position of the prepared bit string.

It is a figure for demonstrating the structure of a barcode reader. It is the figure which represented typically an example of the reading area which a barcode reader reads. It is the figure which represented typically the correction value calculation and correction method of color information. It is a figure for demonstrating the method of comparing a reference | standard primary color data and comparative primary color data, and calculating a color shift correction value. It is a figure for demonstrating correction | amendment of the color information of barcode data. It is the figure which represented typically about the bit structure of the corrected barcode data. It is a flowchart which shows the barcode reading method which reads the barcode classified into three or more colors.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Barcode reader, 11 ... Data reading part, 12 ... Data separation part, 13 ... Reference | standard information storage part, 14 ... Reference | standard information comparison part, 15 ... Correction value storage part, 16 ... Color information correction part, 17 ... Color Information specifying unit, 18 ... used color information storage unit, 19 ... information acquisition unit, 20 ... reading area, 21 ... margin part, 30 ... reference information part, 40 ... barcode part, 31-60 ... small part

Claims (5)

A barcode reader that reads a barcode that is color-coded into at least three colors and acquires information indicated by the barcode,
A data reading means for reading a region including the barcode and its peripheral portion and acquiring read data for specifying a color at a position in the region;
Data separating means for separating the barcode data corresponding to the barcode and the reference data from the acquired read data;
Color information correction means for correcting color information of each of a plurality of data elements constituting the barcode data based on the separated reference data;
For the color information of each of the plurality of data elements constituting the barcode data corrected by the color information correction means, color information that can be used as color information that can constitute the barcode data and the reference data is specified. Color information identification means to perform,
Information acquisition means for acquiring the information indicated by the barcode based on the identification result of the color information identification means;
A bar code reader characterized by comprising:   The data separating means is arranged in a predetermined order at a predetermined position corresponding to the barcode, and corresponds to a primary color component obtained by separating all colors that can constitute the barcode. 2. The barcode reading apparatus according to claim 1, wherein the reference data is obtained by separating the reading data including primary color components.   The color information correction means is a primary color component obtained by decomposing color information included in the reference data with respect to a primary color component obtained by decomposing color information of each of the plurality of data elements constituting the barcode data. The color information of each of the plurality of data elements constituting the barcode data is corrected by performing correction based on a difference obtained by comparing the comparison primary color component prepared in advance with a comparison primary color component. Item 3. A barcode reader according to item 1 or item 2.   The information acquisition means is a binary bit string representing a value representing the lightness of each primary color component of the color information identified as usable in the color information identification means among the barcode data corrected in the color information correction means. The information indicated by the bar code is obtained by decoding the converted bit string and decoding the code added at the time of printing. The barcode reader described in 1. A barcode reading method of reading a barcode color-coded at least three colors and acquiring information indicated by the barcode,
A data reading step of reading an area including the barcode and its peripheral portion and acquiring read data for specifying a color at a position in the area;
A data separation step for separating the barcode data corresponding to the barcode and the reference data from the acquired read data;
A color information correction step for correcting color information of each of a plurality of data elements constituting the barcode data based on the separated reference data;
Color information that can be used as color information included in the barcode data and the reference data for color information of each of a plurality of data elements constituting the barcode data whose color information has been corrected in the color information correction step. Identifying color information identification step;
An information acquisition step of acquiring information indicated by the barcode based on the identification result of the color information identification step;
A bar code reading method comprising:

Images