KR100353872B1 - Machine readable code image and method for encoding and decoding thereof - Google Patents

Abstract

The present invention relates to a machine-readable code and a method and apparatus for encoding and decoding the code, wherein the code includes at least two regions, each region including at least one cell. A data area formed of at least one data cell in which colors, shades, shapes, patterns, or a combination thereof are encoded and displayed according to the content of the information; And a parity region formed of at least one parity cell, which is provided to determine whether colors, shades, shapes, patterns, or a combination thereof displayed on the data cells are appropriately represented corresponding to the contents of the information. In addition, since the code image according to the present invention includes a parity region for parity check, there is an effect of easily detecting and correcting color recognition due to a difference in an environment such as a camera input device or light. .

Description

Machine readable code image and method for encoding and decoding information}

The present invention relates to machine recognizable codes and methods and apparatus for encoding and decoding the codes, in particular to encoding data into codes using arrays of cells represented in various colors or shades, A method and apparatus for decoding the encoded code using a computer and a peripheral device.

In recent years, most products on the market are printed with bar codes composed of lines of various thicknesses to indicate product information such as product types and prices. The bar code is composed of thick lines, thin lines, and double lines to represent numeric data encoded with product information.

On the other hand, there is a case where a uniform resource location (URL), such as an Internet home page address or an e-mail address, is printed on a business card for the purpose of general business. The Internet homepage contains the contents of the company's public relations, and an Internet user interested in the company reads the company's public relations contained in the Internet homepage and attempts to contact the e-mail address when inquiries are made. In addition to the business card, the website or the URL of a specific company may be printed in an advertisement column such as a magazine or a newspaper, and in some cases, an internet homepage address may also be printed in a publication.

At this time, if a user wants to access the URL printed on the business card, the user must type the URL printed on the business card (for example, http://comsciyonsei.ac.kr/~nklee) with the keyboard. Or, if an e-mail address (for example, nklee@yonsei.ac.kr) is printed on a business card, a user who wants to send a letter to that e-mail address must type in the e-mail address.

However, Internet homepage addresses or e-mail addresses do not consist of one or two letters, but generally consist of dozens or tens of letters. This has the disadvantage of being cumbersome for the user to enter the address.

In order to solve this disadvantage, US Patent Publication No. USP 5,869,828 (name of the invention: Color and shape system for encoding and decoding data) has been proposed. USP 5,869,828 is a method and system for encoding / decoding character data using a color figure, and can display information of a product by printing a color figure with a simple configuration on the surface of the product.

Since print characteristics are different for each print, when one color figure is printed with different printers, colors are differently printed due to the characteristics of the printer. In other words, when data is encoded into color figures and the color figures are printed to printers of different companies, the color tone of the color figures may vary according to the characteristics of each printer. Therefore, according to US Pat. No. 5,869,828, an error of failing to properly restore the original information when decoding the printed color figure may occur even if the same color figure is caused by the difference in the printing environment.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and to provide a machine-readable code that includes parity information as well as object data in representing information in code.

Another object of the present invention is to provide an encoding method and apparatus for converting predetermined information into a code as described above.

Another object of the present invention is to provide a decoding method and apparatus for extracting original information from a code encoded by the encoding method.

It is still another object of the present invention to provide a computer readable recording medium having recorded thereon a program for realizing the above encoding and decoding method.

1A-1E are diagrams showing an example of the configuration of a machine readable code according to the present invention.

2A is an example of displaying four colors as two bits, FIG. 2B is an example of a code conversion table for converting various characters, etc. into code images, FIG. 2C is an example of grayscale codes, and FIGS. 2D and 2E are code images. A diagram showing an example of a pattern that can be displayed in each cell of.

3A to 3F illustrate various examples in which the parity region may be located in a rectangular matrix code image.

4 is a diagram illustrating a structure of a database storing index information, and FIG. 5 is a diagram for describing a process of obtaining object information by using index information read from a code image.

6 is a flowchart illustrating a method of encoding information such as characters into a code image according to an embodiment of the present invention.

7 is a diagram illustrating a system for implementing an encoding method according to the present invention.

FIG. 8A is a flowchart for describing a decoding method of using a code image as object information according to an embodiment of the present invention, and FIG. 8B is a detailed flowchart of step 84 of FIG. 8A.

9 is a diagram illustrating a system for implementing a decoding method according to the present invention.

10 illustrates an example of a handbill in which a code image is printed according to the present invention.

11 illustrates various expression examples of code images according to the present invention.

Machine-readable code according to the present invention for solving the above-described problems, the code formed to be machine-readable, which displays a predetermined information, comprising at least two areas, each area includes at least one cell A data region comprising at least one data cell, wherein the color, shade, shape, pattern, or a combination thereof is encoded and displayed according to the content of the information; And a parity region formed of at least one parity cell, which is provided to determine whether colors, shades, shapes, patterns, or combinations thereof displayed on the data cells are appropriately represented corresponding to the contents of the information. It is characterized by including.

Code image encoding method according to the present invention for solving the above problems, (a) code conversion table mapping different colors, shades, shapes, patterns, or a combination thereof corresponding to each recognizable characters including numbers, symbols Setting up; (b) setting object data to be encoded; (c) generating a data area with an image formed by a series of colors, shades, shapes, patterns, or a combination thereof by encoding the object data by the code conversion table; (d) setting a parity area for determining whether or not an image displayed in the data area is appropriately represented corresponding to the object data; And (e) generating a physical or electronic code image from the image of the data region and the parity region.

Code image encoding apparatus according to the present invention for solving the above problems is to store a code conversion table that maps colors, shades, shapes, patterns or combinations thereof differently corresponding to each recognizable character including numbers, symbols Storage unit; A data area generation unit which receives the target data to be encoded and encodes the data by using the code conversion table to generate an image to be displayed in the data area; A parity region generating unit generating a parity region for determining whether or not an image displayed in the data region is appropriately represented corresponding to the object data; And a code image generator for generating a physical or electronic code image from the image formed by the data area and the parity area.

Code image decoding method according to the present invention for solving the above problems, (a) the data area and the image displayed in the image and the data area is encoded as the object data according to the color, shade, shape, pattern or combination thereof Receiving a code image having a parity region for determining whether the expression is properly represented corresponding to the object data; (b) distinguishing and identifying a data region and a parity region from the code image; (c) recognizing color, shade, shape, pattern, or a combination thereof from the images represented in the data region and the parity region; (d) calculating a first parity value according to colors, shades, shapes, patterns, or combinations thereof recognized from images of the data area; (e) calculating a second parity value according to a color, shade, shape, pattern, or combination thereof recognized from the image of the parity region and comparing the first parity value with the first parity value; And (f) extracting the object data of recognizable characters including numbers and symbols by decoding according to the recognized colors, shades, shapes, patterns, or combinations thereof from the data area if there is no parity error as a result of the comparison. Characterized in that,

Another code image decoding method according to the present invention for solving the above problems, (a) the target data is encoded according to the color, shade, shape, pattern, or a combination thereof is displayed in the data area and the data area displayed as an image Receiving a code image having a parity region for determining whether an image is properly represented corresponding to the object data; (b) distinguishing and identifying a data region and a parity region from the code image; (c) recognizing color, shade, shape, pattern, or a combination thereof from the images represented in the data region and the parity region; (d) setting parameters for normalizing code values of colors, shades, shapes, patterns, or combinations thereof recognized from the code images in consideration of the environment in which the code images are read; (e) obtaining code values for the data area and the parity area by normalizing colors, shades, shapes, patterns, or a combination thereof recognized from the code image based on the parameters; (f) calculating a first parity value according to a code value of the data area; (g) generating a second parity value according to a code value of the parity region; (h) comparing the first parity value with the second parity value to determine whether there is a parity error; And (i) if a parity error occurs, resetting the parameter and repeating from the step (e).

Code image decoding apparatus according to the present invention for solving the above problems is to store a code conversion table that maps the colors, shades, shapes, patterns or combinations thereof differently corresponding to each recognizable characters including numbers, symbols Storage unit; The data area represented by the image by encoding the target data according to color, shade, shape, pattern, or a combination thereof, and a parity area for determining whether or not the image displayed on the data area is appropriately represented corresponding to the target data. An input unit including a code image encoded by the code conversion table; An information identification unit for discriminating and identifying a data area and a parity area from the code image, and determining a color, a shade, a shape, a pattern, or a combination thereof of each cell displayed in the data area and the parity area; A first parity value is calculated according to a color, shade, shape, pattern, or combination thereof recognized from the image of the data area, and according to the color, shade, shape, pattern, or combination thereof recognized from the image of the parity area. A parity comparison unit for calculating a second parity value and comparing it with the first parity value; And a recognizable character including numbers and symbols by decoding by the code conversion table according to the color, shade, shape, pattern, or combination thereof recognized from the data area if there is no parity error as a result of the comparison of the parity comparison unit. It characterized in that it comprises a data extraction unit for extracting data.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

FIG. 1A is a diagram showing an example of the configuration of a code formed of an image so that predetermined target information can be machine-readable in accordance with the present invention. The code includes at least two regions, and each region includes at least one cell. The code includes a data region 11 formed of at least one data cell in which colors, shades, shapes, patterns, or a combination thereof are encoded and displayed according to the content of the information. It is also possible to vary the shape of the cell or to add a predetermined pattern into the cell.

The code may further include a parity region 13, a reference region 15, and / or a control region 17. The parity area 13 is formed of parity cells for checking a recognition error of cells displayed in the data area 11. The reference area 15 includes at least a reference color, a reference jog, a reference shape, a reference pattern, or a combination thereof for determining the color, shade, shape, pattern, or combination thereof of the data cells formed in the data area 11. It is formed of one reference cell. The control area 17 is formed of at least one control cell indicating a command or a service which can be provided using the information displayed in the data area 11. Hereinafter, regions other than the data region, for example, a region including a parity region, a reference region, and a control region, are collectively referred to as an "secondary region", and a cell included in the auxiliary region is referred to as an auxiliary cell.

In addition, it is preferable to further include a boundary area for distinguishing areas between each area included in the code. In addition, a boundary area for distinguishing cells may be further provided between each cell included in each area. The boundary area may be composed of lines or cells of a specific color or pattern, and the boundary line or boundary area may be black or white. On the other hand, by distinguishing and setting the range of colors or shades that can be displayed in each cell of the data area, parity area, reference area, or control area, these areas can be distinguished, or special patterns are different for cells belonging to each area. Insertion method can be used. On the other hand, such a boundary area may not be displayed for the security of code information.

The data area 11 is composed of one or more data cells in which characters and the like are encoded into an image. The data cells may be configured such that each represents information such as one character, and the plurality of data cell sets may also be configured to represent one or more information. For example, the letter "A" may be displayed as one cell in red or two cells in red and green.

The purpose information contained in the data area 11 is composed of letters, numbers, symbols, etc., name, address, telephone number, fax number, host address of the network, domain name and IP address used in the Internet, URL, protocol, Or it can be various according to user's needs such as document name.

The parity area 13 is used to determine whether colors or shades (shape and / or pattern, if any) are appropriately represented in the data cells corresponding to the contents of the object information. The parity region obtains parity data according to a code value defined in correspondence with a color or shade displayed on the data cells, forms a parity cell with colors or shades corresponding to the parity data, and the parity cells are located in the code image. Are shown in FIGS. 3A-3F.

The reference area 15 is a reference color (or reference joke, if necessary) that recognizes the colors (or shades, shapes or patterns, if any) expressed in the cells in the data area 11 and / or the auxiliary area. Reference pattern). The color of the cell displayed in each area is displayed based on at least one of a red blue green (RGB) color model and a hue saturation value (HSV) color model. In addition, even when codes are formed by black and white shades (gray scale), the information of each cell can be accurately recognized based on the black and / or white displayed on the reference area 15.

Depending on the type of printing or the material of the printing paper, even one color may be printed differently, and the same color may be recognized differently depending on the characteristics of the scanner or camera. In view of this, the reference cell in the reference area 15 provides a criterion for determining the color displayed in the data area. That is, even if the color is output differently according to the output device or the color is input differently according to the input device such as a scanner, the color difference between the color of the reference area 15 and the color of the data area 11 is different. Since it is fixed, the color of the cell represented in the data area 11 can be accurately recognized. Therefore, since the color displayed in the cell of the data area 11 has a relative color difference compared with the reference color of the reference area 15, the color is compared with the reference color of the reference area 15 based on the RGB model or the HSV model. By obtaining the color of the cell in the data area 11, even if the image input device or the output device is changed, it is possible to accurately recognize the information of the data cell. When a shape or a pattern is input to an input device such as a camera, it may be input in a tilted or crushed state. By providing the reference shape or the reference pattern by the reference area, it is possible to detect such a mis-input state to accurately recognize the shape or pattern expressed in the data cell.

The user may be provided with various services according to the application by using the object information of the data area 11. For example, if a business card displays the homepage address (ie URL) of the Internet as a code image, decode the code image into a computer and then launch the WEB browser of that computer or a server computer connected to that computer. Can be programmed to access the home page. In addition, if the e-mail address of the Internet is displayed as a code image, an environment in which the code image can be decoded to a computer and then mailed to the e-mail address by executing mailing software of the computer. Can be provided. As another example, when a code image is input to a portable terminal, a phone number corresponding to the code image may be dialed or a geographic information service may be provided. At this time, the automatic service function may be automatically executed by a separate program or in accordance with the type of object information in the decoding program. In addition, it is possible to include a control region 17 represented by an image such that a separate command is included in the code image, so that it can be automatically serviced by the decoding program using the control information decoded in the control region 17.

In addition, the control area 17 may include a command or meta-data for controlling object information of the data area. For example, the information displayed in the control region 17 may be a reference cell of the reference region 15 that serves as a criterion for decoding the cells formed in the data region 11 or the color of the data cells formed in the data region 11. It may include various meta information, such as the position of, the position of the parity area 13, or the attribute.

1B-1E illustrate examples of relative positional relationships in which a data region and an auxiliary region (parity region, reference region, and / or control region) are represented in a code image. In the drawing, hatched areas indicate auxiliary areas.

2A shows an example in which two bits of data can be represented in four colors. If each cell can have any one of four colors, one color cell can represent two bits of data. Then, if it is defined to display one character as four consecutive cells, it can represent 8 bits, or 256 characters. On the other hand, if you have four types of shapes that have the same color but a cell can have (eg, small square, large square, small circle, large circle), two bits of data can be represented. If it can be filled with different colors, 256 (8 bits) of information can be represented. FIG. 2B is a diagram illustrating an example of a code conversion table for converting various characters (alphabet, special characters, etc.), numbers, or shapes into an image, in which one character is mapped to two color cells.

In the encoding method using the code conversion table of Fig. 2B, various characters and the like are converted into code values, and then code images are generated with colors (colors) assigned to each code value. In this example, code images are generated using eight colors, and two consecutive cells are used to represent one letter or number. For eight colors, code values from "000" to "111" are assigned, and each character is encoded in two colors. For example, the number "3 " is assigned to the code value " 000 011 " and is encoded into the color (black) assigned to the code value " 000 " and the color (white) assigned to the code value " 011 " It is imaged as two cells in succession to cyan. According to the code conversion table shown in FIG. 2B, various characters or numbers included in the object information may be converted into code values, and then the color corresponding to the code values may be expressed in a rectangular matrix form of a combination of square cells.

2C illustrates an embodiment of generating a code image using greyscale code in accordance with the present invention. Although the present invention can be encoded and decoded as color using a color printer and a scanner, it is shown that a code image can be generated using grayscale code, that is, black and white shades according to a user's use and situation.

Grayscale codes form codes according to the brightness of black and white instead of the mixing ratio of R (Red), G (Green), and B (Blue). Accordingly, the reference area is either black, white, or gray, which is set as the reference light, and the cell in the data area has a value coded by the gray difference compared to the reference light of the reference area. If the reference region is not in the code image, the shade of each cell of the code image is calculated, the cells having similar shades (cellset) are collected, the same code value is assigned to cells belonging to the same cellset, and then the parity region is used. Decoding error can be determined. If a discriminant error occurs, the color tone of each cell is recalculated or a criterion for forming a cell set is set differently, and then an error is again determined. This grayscale code image can be applied to a medium mainly printed in black and white, such as a newspaper.

2D and 2E illustrate an embodiment of a pattern that can be displayed in each cell of a code image according to the present invention. In converting information into a code image, it is shown that a method of adding a pattern to a color cell using a vector line in addition to color can be employed. 2D illustrates an example of four-way and eight-way vector lines that may be displayed in a cell. If four-way vector lines are used, as shown in FIG. 2E, 16 different patterns (4 bits) may be added to the color of each cell. Therefore, when 8 colors (3 bits) are used, 128 types (7 bits) of characters can be represented in the code image. In addition, by dividing the cells in the horizontal, vertical or diagonal direction, it is possible to express colors or shades differently.

As described above, in the image code according to the embodiment of the present invention, not only various colors and shades but also shapes or patterns are combined with each other to express a data area and / or an auxiliary area. For example, various types of information may be expressed by changing shapes or by changing patterns represented in cells by using one or several colors.

11 is a diagram illustrating various expression examples of code images according to the present invention. In the drawing, the shape of the cell can be variously implemented in a square, circle, oval, cross, or honeycomb, etc., and combinations of these shapes can be made while forming one image code. Depending on the content or amount of information to be displayed in the code image, the shape and size of the code image or the cells can be selected as appropriate. In addition, Figure 11h shows that the encoding scheme of the present invention can be applied while having a shape similar to a barcode.

3A to 3F illustrate various examples in which the parity region 13 of FIG. 1 may be located in the code image in the case of a rectangular matrix code image. Even when the code image has a circular or other shape, the configuration described in this example can be applied. An area Dn other than the area indicated by the parity area Pn is a data area, a reference area or a control area.

3A illustrates an example in which parity cells having parity information about cells in the same row are displayed in the rightmost column. For example, the parity cell for D11, D12, D13, and D14 cells is P1. 3B illustrates an example in which parity cells having parity information of cells in the same column are displayed in a diagonal direction. FIG. 3C illustrates an example in which parity cells having parity information of cells in the same column are displayed in a lowermost row. 3D illustrates an example in which parity cells having parity information of cells in the same row are displayed in a diagonal direction.

FIG. 3E illustrates parity cells P1r to P4r having parity information about cells in the same row and parity cells having parity information for cells in the same column while displaying parity cells P1r to P4r in the rightmost column. P1c to P4c) show an example shown in the bottom row. And an additional parity cell Prc having parity information for column parity cells and row parity cells. 3F illustrates a code including column parity cells P1r to P4r and row parity cells P1c to P4c similarly to FIG. 3E, where the column parity cells P1r to P4r are arranged in a diagonal direction. . The row parity cells P1c to P4c may be arranged in a diagonal direction.

Next, an example of a method of selecting the color displayed on the parity cell will be described. One parity cell has a code value obtained as a result of an exclusive OR operation of code values of data cells (which may also include a reference cell and a control cell) placed in the same column or the same row. Different types of parity techniques can be applied depending on the number of colors or tints applied to code images.

For example, if there are two kinds of colors or shades, even parity and odd parity may be used. In the case of using an even parity method, an operation result value immediately becomes a code value to form a parity cell in a color corresponding to the code value. When using an odd parity scheme, a complement value of each bit of an operation result value is obtained, and a parity cell is formed in a color corresponding to the value.

If a color to be displayed on the parity cell using the code conversion table shown in Figure 2a is as follows. If the colors of the data cells D11, D12, D13, and D14 are black, red, green, and green, the code values are 11, 10, 01, 01. (XOR = exclusive OR)

Even parity method

11 XOR 10 XOR 01 XOR 01 = 01 (green)

Odd parity scheme

11 XOR 10 XOR 01 XOR 01 = 01-> to 01 = 10 (red)

However, if the number of colors or shades used in the code image increases, one of the various parity schemes may be applied. If you use four kinds of colors or shades, there are four possible parity methods. That is, in addition to even parity and odd parity, 2 is added to the parity value obtained by using the modular and parity values obtained by adding the parity value obtained by the even parity method. There is an odd modular parity method that adds the remainder divided by 4 to the parity value. If you use eight colors or shades, eight parity schemes are available. In general, when there are N colors or shades used in the code image, the types of parity methods that can be used are as follows.

("Parity value obtained by the even parity method" +2 * i)% N,

("Parity value obtained by odd parity" + 2 * i)% N,

Where i = 0,1,2, .., log ₂ N-1, N = 2,4,8, ....%: modular

Using the above four examples, the four parity schemes are applied as follows.

Even parity method

11 XOR 10 XOR 01 XOR 01 = 01 (green)

Even Modular Parity Method

(01 ₂ +10 ₂ )% 4 = 11 ₂ (black)

Odd parity scheme

11 XOR 10 XOR 01 XOR 01 = 01-> to 01 = 10 (red)

Odd Modular Parity

(~ 01 ₂ +10 ₂ )% 4 = 00 ₂ (blue)

By applying a plurality of parity methods to one code image at the same time, it is possible to determine the type of code, the decoding method, the direction of reading the cell, etc. according to the type or shape of the applied parity method. For example, referring to FIG. 3E, the first parity is indicated in the last cells of the row and the column according to the even parity method for each row and each column, and the odd number is present in the cell Prc at the position where the row parity and the column parity intersect. The second parity is indicated according to the parity method. Then, when the first and second parity cells are obtained in the decoding process, the order of the cells to be decoded in the code image may be known. As another example, referring to FIGS. 3A, B, and C, different parity schemes may be applied to each row or column. For example, an even parity scheme may be applied to the first column and an odd parity scheme may be applied to the remaining columns. Then, it can be seen that the column to which even parity is applied is the first column during decoding. On the other hand, instead of expressing the parity value in color or shade, it can be expressed using a shape, a pattern or a combination thereof. For example, if the parity value is 00, a white square may be displayed, a black square if 01, a white circle if 10, and a black circle 11 may be displayed. In addition, the display apparatus may further include a cell (or region) on which information indicating a parity scheme applied to the code image is displayed.

6 is a flowchart illustrating a method of encoding information such as characters into a code image according to an embodiment of the present invention. The information is converted into a code image by the encoding software as follows. One or more letters or numbers included in the object information are converted by a predetermined code conversion table as shown in FIG. 2B and converted into code images having a predetermined shape, color, pattern, or a combination thereof.

First, the encoding method may be classified into a direct encoding method, an indirect (or index) encoding method, and a mixed encoding method according to the type of information encoded into the code image. The direct encoding method refers to a method of generating a code image by directly encoding object information by a code conversion table. Indirect encoding is a method of encoding the index information (for example, the address or record number of the database) for referencing the target information by using a code conversion table to convert the form into an image. There is a mixed encoding method in which the two methods are mixed.

The direct encoding method encodes the target information itself into a code image, and does not require a separate system or a separate storage location, but when the amount of data of the target information increases, the physical size of the code image also increases.

The indirect encoding method encodes the positional information of the storage location where the object information is stored without encoding the object information itself. The location information may be a pointer or a memory address of a storage location where the destination information is stored, or a URL or an IP address indicating the location of the destination information. Therefore, the indirect encoding method requires a separate system or storage location where the target information exists.

In the mixed encoding method, some data essential for the entire purpose information is encoded by the direct encoding method, and other data is encoded by the indirect encoding method. For example, a name and a telephone number are encoded for each character, data having a large amount of data such as a postal address or an email address is stored in a server, and a code image is generated by encoding a memory address of the data stored in the server. In addition, it is preferable to apply a direct encoding scheme to fixed data such as a name, and to apply an indirect encoding scheme to variable information that may change from time to time, such as a homepage address, a telephone number, or an e-mail address. If a user registers the change in the database of the server when his / her personal information is changed, the person who receives the business card displaying the user's code image can always access the latest information even with the previously received business card.

4 is a view for explaining an embodiment of a structure of a database that stores index information required when applying an indirect encoding method in the encoding method according to the present invention. FIG. 5 is a diagram illustrating index information read from a code image. A diagram for describing a process of obtaining objective information. In FIG. 5, together with the index database 51 as shown in FIG. 4, a service pointer database 52 in which pointer information for accessing actual object information according to each index information is stored is provided. The pointer information is information indicating a location where the actual purpose information 53 such as a message, an image or a video is stored.

A unique index is allocated for each actual purpose information (content), and a service code and an offset corresponding to the purpose information are set and stored together. Here, the purpose information is the final information that the user can ultimately use, and includes various information such as a website address, an email address, a message, an image, a video, and music. The service code is a code designated for each service type, for example, the web access service may be coded as "1", the telephone call service as "2", and the like. The offset is information about the location to access the service pointer database 52. For example, when index information is read from the code image, the index database 51 is searched to extract a service code, an offset, and objective information about the index. The pointer information stored in the service pointer database 52 is found according to the offset. Based on the pointer information, find the location of the preset message or picture file and provide the contents to the user. For example, the service type code is acquired in the first database and the location information is obtained in the second database using the object data obtained by decoding the code image. After the purpose information is acquired according to the location information, a service determined by a service type code, for example, a message service, a video service, a web page access service, a telephone service, an e-mail service, etc. is provided using the purpose information.

An encoding process will be described with reference to FIG. 6. A code conversion table in which color or shade (if necessary, shape or pattern) is mapped is set corresponding to each recognizable character including numbers and symbols (61). An example of the code conversion table is shown in FIG. 2B, and a pattern (see FIG. 2E) such as a cell shape or a vector line may be applied to the mapping method.

The user inputs object information to be converted into a code image (62). The user inputs a name, affiliation, telephone number, fax number, etc., for example, in order to encode personal information to be displayed on a business card into a code image. Servers usually store user-entered information in a database or file.

Next, it is determined whether a direct encoding method for directly encoding the object information is applied or whether an indirect encoding method for encoding the position information stored in the database is applied (63). If the direct encoding method is applied, the object information itself is set as the object data to be encoded (64b), and if the indirect encoding method is applied, the position information of the object information is set as the object data to be encoded (64a). ). For example, encoding the personal information (object information) input by the user is a direct encoding method, and when the personal information is encoded an address of a database stored in a server or an index related to the address, an indirect encoding method is used. In addition, a mixed encoding scheme may be applied in which a direct encoding scheme is applied to a name and an indirect encoding scheme is applied to the remaining personal information.

The target data is encoded by the code conversion table (65). Then, a code value corresponding to a character, a number, or the like included in the object data is obtained, and the image to be displayed in the data cell is determined by the color or tint determined by the code value, and the order of characters in the object data is arranged ( Or arranged in accordance with a predetermined method) to complete the data area. After encoding of the object data, at least one of the parity information, the reference information, and the control area is determined as the type of auxiliary information to be displayed on the code image (66). In addition, a display method of auxiliary information, for example, a parity method, is selected.

On the other hand, if the reference area is displayed in the auxiliary area, a reference color or reference joke is determined to provide an interpretation criterion of the color or tint displayed on the data cells of the data area, and the shape or position of the reference cell to be displayed or By defining an array, you can set up more reference areas. In addition, a control region encoded with control information that sets a command or service item that can be used using the purpose information included in the data region may be further set.

Next, if the parity area is displayed in the auxiliary area, the parity value is obtained according to the parity method set in the encoding process by using the code value of the color or shade (if necessary, shape or pattern) displayed on the data area. A color or shade (or shape or pattern, if necessary) corresponding to the value is set and generated as parity data (66). At this time, the region where the parity cell is to be determined is determined (see FIGS. 1 and 3A-3F).

When the data area and the auxiliary area are set, the layout of the code image is set including the shape in which the code image is displayed, the relative position and size of each area, and the size of the unit cell. A code image consisting of a data area and an auxiliary area is generated according to a predetermined layout (67). Code images can be automatically output by the program's algorithms, or they can be created by a graphical editor or by hand, depending on the code conversion scheme. The generated code image is displayed on a predetermined medium or stored as an image file.

7 is a diagram showing a system for implementing an encoding method according to the present invention. The computer 77 receives input information and generates a code image by the encoding method as described above, and generates a code image by the printer 78. May be physically displayed on a medium 79a such as a business card or provided as a code image file 79b in the form of an image file. Here, the media on which the code image is to be displayed includes all media for displaying predetermined information such as a business card, an outer surface of a product, or an advertisement surface of a magazine. In addition, the code image may be output to a display device such as a monitor, may be stored in a computer file, or may be transmitted as an electrical signal on a communication line.

8A is a flowchart illustrating a decoding method of extracting original object information, such as characters, from a code image according to an embodiment of the present invention. To decode the code image of the present invention, as shown in FIG. 9, an image input device 92 such as a scanner, a digital camera, a CCD camera, a sensor, a fax, etc. for reading the code image 91a or a computer 93 is provided. It can be provided in the form of a code image file 91b that can be used directly from. Then, a computer system (a personal computer or a server computer connected to the personal computer) 93 on which a program for decoding the code image is to be executed must be equipped.

First, a code image formed of a data area and an auxiliary area is input to a user computer (80). The user computer can directly receive the code image 91a displayed on the medium using the image input device, and can load the image file 91b that has already been created into the memory through a storage device such as a disk or a buffer. If the code image is an indirect encoding method, it must be connected to a server having a storage device for storing the index information or provided on the user computer itself.

The image inputted by the image input device is subjected to image processing using already set parameters, and then extracts the code image. This may be applied to edge detection or noise image rejection by region extraction. Depending on the operating state of the scanner or the position where the code image is printed on the media, the code image may be read skewed or skewed. In this case, since the code image may be decoded erroneously, the position or direction of the code image is correctly corrected (81). Even if the correction process is not performed, the position of each cell can be determined by considering the inclined state.

The data area and the auxiliary area (parity area, reference area and / or control area) are distinguished from the code image by using information of the boundary area set between each area or information of a cell containing specific information. 82). If there is a reference area, it is used to determine the color, shade, shape, and pattern expressed in each cell. If there is a parity area, it is determined whether an error occurs in the data cell.

When the code image is recognized by the computer, a decoding process of extracting original information therefrom is performed. Decoding involves finding the original information from the code image as defined in the code conversion table. Decoding methods include a direct decoding method and an indirect decoding method according to a method of encoding information. In the direct decoding method, when the code image is decoded, actual object information such as name or address is extracted immediately. In the indirect decoding method, the decoded result has index information, which is a key value for accessing a database storing actual object information such as a name and an address.

In the decoding process, it is necessary to find out the shapes, colors, patterns, and characters included in the code image, and to correct the distorted image. Here, using at least one method of RGB (Red, Green, Blue) model, HSV (Hue angle, Saturation, Value) model, CMY (Cyan, Magenta, Yellow) model, HLS (Hue angle, Lightness, Saturation) model Color discrimination is possible.

For decoding, the code values of the cells in the data area and / or the auxiliary area are extracted (83). If there is a reference area, the color or shade of the reference cell is detected and used as the reference color (or shade), the reference shape or the reference pattern which is a reference for analyzing the information of all the areas including the data area. Colors, shapes, and patterns of cells in the data area, parity area, or control area are detected, and then differences between the reference color, reference shape, and / or reference pattern are detected and converted into code values for each cell. If there is no reference area, a code value corresponding to each cell can be obtained according to the color, shade, shape and / or pattern read by the image input apparatus.

If there is a parity region, a process of checking whether there is an error in parity for each column and row of the code image is performed based on a code value obtained from the parity region, that is, parity data (84). This will be described later with reference to FIG. 8B. If necessary, the direction or position of the code image can be searched based on the parity data.

The code values of the cells obtained by the above-described process are converted into object data of recognizable characters including numbers and symbols by the code conversion table (see FIG. 2B). The content of the object data obtained in step 85 is determined according to an encoding method (86). If the code image is encoded by an indirect encoding method, that is, if the object data is index information, the object data obtained by decoding corresponds to an address or a pointer of a storage location in which the object information is stored, and thus the storage device defined by the object data ( The target information stored in the location of the database) is extracted (87a). If the object data is not index information, the object data obtained by decoding soon becomes desired object information (87b).

If there is a control area in the code image that sets the details of the command or service that can be used by using the objective information (88), the command or service is provided according to the information set in the control area (89a). Provide the specified basic service (89b).

FIG. 8B is a detailed flowchart of step 80 of FIG. 8A, which illustrates a process of checking parity based on the code value extracted in step 84 and correcting color according to the inspection result. First, a parameter for color reading is set (841). The parameter can be set to R, G, B of RGB model or H, S, V of HSV model, or a combination thereof, and normalizes the code value of color or shade recognized from code image in consideration of the environment where code image is read. Is set to. In this case, R, V, and S values, that is, R values obtained from an RGB model, V values obtained from an HSV model, and S values may be used. In general, initial environmental parameters are set to suit the most commonly used lighting environment, such as fluorescent or three wavelength lamp lighting. Alternatively, before entering the code image with the camera, it is preferable to first photograph the white paper against the background and set the parameters according to the lighting environment around it. For example, under halogen lamp lighting, red light is relatively strong, so set the parameter to eliminate the effect of red light caused by halogen lamps. Then, normalizing the color actually read by the parameter can reduce the influence of illumination and obtain a color close to the original color.

Then, based on the parameters R, V, and S, the RGB values of the colors read from the code image are normalized (842). A code value corresponding to a color according to a normalized RGB value is obtained by a code conversion table (843). The parity value is calculated according to a code value of cells in each row and / or column displayed in the data area and / or the auxiliary area (844). The calculated parity value is compared with the parity data of the parity cell set for each row and column of the data area to determine whether there is a parity error (845). In this process, if a plurality of parity schemes are applied to the code image, not only parity check but also a decoding order of cells included in the code image may be easily detected.

If a parity error occurs in a row or column, the new environment parameter is set 846 to perform again from the color normalization step. Parameters optimized for a high frequency lighting environment and weights thereof may be preset and stored in a decoding program or in a database so that the user may select an environment parameter that is most suitable for his environment. The occurrence of a parity error can be considered to be an error in the decoding of the color by the currently set parameter, in which case the other parameters are applied to read the color again.

In the parameter database, the parameters are set experimentally to analyze the optical characteristics of the input optical device and ambient lighting conditions so that the color read by the input optical device can be corrected to the original color or to distinguish the code image from the background. It eliminates the influence of the environment and enables color recognition without error. It is also possible to form two or more parameter groups with different purposes. In other words, one parameter may be set to separate the code image from the background, and the other parameter may be set to determine the color or tint of the code image separated from the background. For example, when a color is determined based on an RGB model in a red-lighted environment, the R value is relatively high, so that the R value read by the optical device is reduced according to a predetermined weight to exclude the influence of the environment. In addition, the code image input in the brightly lit environment increases the weight of the V value to distinguish the color based on the HSV model. In the dark lighting environment, the color of the HSV model is determined by reducing the weight of the V value distinguishing black and white from the color, and reducing the weight of the S value. Also, in resetting the parameter, the optical device grasps the distribution of R, G, B, H, S and / or V values obtained for each cell of the code image, and refers to the parameter and You can reset the weight for.

On the other hand, in the decoding process as described above, if a read error occurs for the code image continuously, the user can directly input the target data with reference to the code conversion table according to the color displayed on the code image. Then, the service is provided according to the purpose data.

10 illustrates an example of a handbill in which a code image is printed according to the present invention. A user viewing the handbill of FIG. 10 may obtain (or capture) information corresponding to a code image by scanning (or photographing) a code image (a rectangular matrix image displayed at the lower left and right sides of the drawing) with an optical device such as a PC camera or a scanner.

The invention can also be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, and may also be implemented in the form of a carrier wave (for example, transmission over the Internet). Include. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

As described above, since the code image according to the present invention includes a parity region for parity check, it is possible to easily detect and correct color recognition due to a difference in environment such as a camera input device or an illumination condition. It works. Therefore, a more efficient decoding method and decoding apparatus can be implemented using the code image of the present invention.

According to the present invention, according to the code conversion table, the parity information is encoded together with the object information into the code image, the parity check is performed in decoding the encoded code image, and the color is accurately applied by appropriately applying environment parameters when a parity check error occurs. I can recognize it. In particular, the present invention can accurately recognize the information of the code even in the environment of normal brightness under normal fluorescent lighting, relatively dark or bright environment, and the environment with strong red light such as under halogen lighting.

Claims (25)

In a machine-readable code for displaying display information consisting of recognizable characters including numbers, symbols, According to the mapping relationship with the color or the tone that is set corresponding to each recognizable character, each character included in the display information is converted into a color or a tone and expressed in at least one data cell to correspond to the character included in the display information. A data area including the data cells imaged and displayed in a combination of colors or shades, and displaying an image corresponding to the display information; And Parity information for determining whether or not an image formed by a combination of colors or shades in the data area is appropriately represented according to the mapping relationship corresponding to the characters in the display information is a combination of colors or shades. And a parity region on which an image corresponding to the parity information is displayed, comprising at least one parity cell imaged and displayed. 2. The apparatus of claim 1, wherein the parity region obtains parity data according to a code value defined corresponding to a combination of colors or shades displayed on the data cells, and forms parity cells with colors or shades corresponding to the parity data. Machine-readable code, characterized in that. The method of claim 1, wherein when the data cells of the data area are formed in a plurality of columns and rows, parity cells for data cells in the same row are displayed in the rightmost column or are displayed in a diagonal direction. Machine readable code. The method of claim 1, wherein when the data cells of the data area are formed in a plurality of columns and rows, parity cells for data cells in the same column are displayed in a lowermost row or in a diagonal direction. Machine readable code. The data cell of claim 1, wherein when the data cells of the data area are formed of a plurality of columns and rows, parity cells for data cells in the same row are displayed in the rightmost column and data in the same column. Machine-readable code, characterized in that the parity cells for the cells are displayed in the bottom row. The data storage device of claim 1, further comprising a reference area formed of at least one reference cell providing a reference color or a reference joke for determining the color or tint of the data cell formed in the data area, or the information displayed in the data area. And a control area formed of at least one control cell for indicating a command or a service which can be used. The method of claim 1, wherein in the data area, when converting a letter or a number into an image for representing a cell, not only colors or shades, but also shapes of cells or patterns including vector lines are used, and cells are horizontally and vertically. Or differently expressing colors or shades by dividing in a diagonal direction. The machine-readable code of claim 1, further comprising a boundary line or a boundary area for distinguishing an area or a cell between each area included in the code or between each cell included in each area. The apparatus of claim 1, wherein the information is at least one of a letter, a number, a symbol, a name, an address, a phone number, a fax number, a network address, a domain name, an IP address, a URL, a protocol, and a document name. Possible code. (a) setting a code conversion table in which colors, shades, shapes, patterns, or a combination thereof are mapped differently in correspondence with each recognizable character including numbers and symbols; (b) setting object data to be encoded; (c) generating a data area with an image formed by a series of colors, shades, shapes, patterns, or a combination thereof by encoding the object data by the code conversion table; (d) setting a parity area for determining whether or not an image displayed in the data area is appropriately represented corresponding to the object data; And (e) generating a physical or electronic code image from the image of the data area and the parity area. The method of claim 10, wherein step (d) Obtaining a prescribed code value corresponding to a color, shade, shape, pattern, or combination thereof displayed on each data cell of the data area; Obtaining a parity code value based on code values of the data cells; And And obtaining a color, shade, shape, pattern, or combination thereof corresponding to the parity code value, and displaying the color, shade, shape, pattern, or combination thereof on the parity cell of the parity region. The method of claim 10, further comprising: setting a reference area in which a reference color, reference joke, reference shape, reference pattern, or a combination thereof is provided which provides an interpretation criterion of a color, shade, shape, pattern, or combination thereof displayed in the data area. And setting up a control area in which items relating to a command or a service that can be used by the target data included in the data area are set. 11. The code image encoding method of claim 10, wherein the object data is object information which is actually information of interest or location information related to a location of a storage location where the information of interest is actually located. A code image generated by encoding object data by the encoding method according to claim 10. A storage unit for storing a code conversion table in which colors, shades, shapes, patterns, or a combination thereof are mapped differently in correspondence with each recognizable character including numbers and symbols; A data area generation unit which receives the target data to be encoded and encodes the data by using the code conversion table to generate an image to be displayed in the data area; A parity region generating unit generating a parity region for determining whether or not an image displayed in the data region is appropriately represented corresponding to the object data; And And a code image generator for generating a physical or electronic code image from the image formed by the data area and the parity area. (a) a code image having a data area encoded with colors or shades and having a parity area for judging whether or not an image displayed on the data area is appropriately represented corresponding to the object data. Receiving an input; (b) distinguishing and identifying a data region and a parity region from the code image; (c) recognizing color, shade, shape, pattern, or a combination thereof from the images represented in the data region and the parity region; (d) calculating a first parity value according to colors, shades, shapes, patterns, or combinations thereof recognized from images of the data area; (e) calculating a second parity value according to a color, shade, shape, pattern, or combination thereof recognized from the image of the parity region and comparing the first parity value with the first parity value; And (f) if there is no parity error as a result of the comparison, decoding the data according to the recognized colors, shades, shapes, patterns, or a combination thereof to extract the object data of recognizable characters including numbers and symbols; Code image decoding method, characterized in that. 17. The method of claim 16, further comprising the step of extracting the information at the location of the storage location defined by the destination data, when the extracted object data is the location information related to the location of the storage location where the information is actually located. Code image decoding method, characterized in that. (a) Determining whether or not the target data is encoded according to color, shade, shape, pattern, or a combination thereof and whether or not the data area represented by the image and the image displayed on the data area are appropriately represented corresponding to the object data. Receiving a code image having a parity area for the code; (b) distinguishing and identifying a data region and a parity region from the code image; (c) recognizing color, shade, shape, pattern, or a combination thereof from the images represented in the data region and the parity region; (d) setting parameters for normalizing code values of colors, shades, shapes, patterns, or combinations thereof recognized from the code images in consideration of the environment in which the code images are read; (e) obtaining code values for the data area and the parity area by normalizing colors, shades, shapes, patterns, or a combination thereof recognized from the code image based on the parameters; (f) calculating a first parity value according to a code value of the data area; (g) generating a second parity value according to a code value of the parity region; (h) comparing the first parity value with the second parity value to determine whether there is a parity error; And (i) if a parity error occurs, resetting the parameter and repeating from the step (e). 19. The method of claim 18, wherein the parameter of step (d) is R, G, B of the RGB model, H, S, V of the HSV model, or a combination thereof. 19. The code image decoding method according to claim 18, wherein the step (d) first captures a white background before inputting the code image to the image input apparatus and sets a parameter according to the lighting environment around the image. 19. The code image decoding of claim 18, wherein the step (d) comprises pre-setting and storing optimized parameters for various lighting environments, and allowing a user to select a parameter most suitable for his environment. Way. 19. The method of claim 18, wherein in resetting the parameter in the step (h), the distribution of the color or shade obtained for each cell of the code image is determined, and the parameter and its weight are reset with reference to the distribution. Code image decoding method characterized in that. 19. The apparatus of claim 18, wherein the code image further includes a reference area in which a reference color, a reference joke, a reference shape, a reference pattern, or a combination thereof is provided, which provides an interpretation criterion of a color or a tone displayed in the data area. Code image, characterized in that to determine the color, shade, shape, pattern, or combination of each of the cells displayed in the data area based on the reference color, reference joke, reference shape, reference pattern or combination thereof displayed on the area. Decoding method. A storage unit for storing a code conversion table in which colors, shades, shapes, patterns, or a combination thereof are mapped differently in correspondence with each recognizable character including numbers and symbols; A parity area for determining whether the object data is encoded according to color, shade, shape, pattern, or a combination thereof and whether or not the image displayed on the data area is appropriately represented corresponding to the object data. An input unit including a code image encoded by the code conversion table; An information identification unit for discriminating and identifying a data area and a parity area from the code image, and determining a color, a shade, a shape, a pattern, or a combination thereof of each cell displayed in the data area and the parity area; A first parity value is calculated according to a color, shade, shape, pattern, or combination thereof recognized from the image of the data area, and according to the color, shade, shape, pattern, or combination thereof recognized from the image of the parity area. A parity comparison unit for calculating a second parity value and comparing it with the first parity value; And If there is no parity error as a result of the comparison of the parity comparison unit, the object data of recognizable characters including numbers and symbols is decoded by the code conversion table according to colors, shades, shapes, patterns, or combinations thereof recognized from the data area. Code image decoding apparatus comprising a data extraction unit for extracting. A computer readable recording medium having recorded thereon a program for realizing the method according to any one of claims 10, 16 and 18.