Research On Color Two Dimensional Coding Technology

As a rapid reading technology,bar code has been widely used in commodity settlement,logistics transportation,warehouse management and other fields.One dimensional bar code and two-dimensional bar code are common.Two dimensional bar code is widely used in mobile payment,e-commerce,product traceability and other fields.At present,black-and-white two-dimensional bar code is applied in the market.This paper will study how to add color information to black-and-white two-dimensional bar code to improve information storage capacity and security.In this paper,QR code,which is the most widely used in the market,is taken as the research object.In order to increase the information capacity,color information is added to the QR code lattice diagram to transmit additional information.The information transmitted by QR code lattice diagram is called "original information",and the additional color information is called "additional information".The original information follows the coding rules of QR code to generate QR code lattice;The additional information is added to the black module of the data area to generate the color QR code.The color QR code contains not only the dot matrix information of QR code,but also additional color information,so as to increase the storage capacity and information density;Through the fence encryption algorithm for encryption,improve information security,enhance anti-counterfeiting function.The main tasks of this project are as follows:(1)Color QR code coding.The coding of color QR code is divided into two parts:one part of the original information is coded according to the coding rules of QR code to generate the QR code dot matrix;The other part of the additional information is divided into four modes according to the data type,and then the additional information is encrypted by rail fence cipher to get the encrypted additional information;Then the encrypted additional information is encoded by four colors corresponding to the Quaternary coding rules to get the data codeword,and then the RS error correction algorithm is used to correct the error,and the error correction codeword is added to the data codeword to get the total data codeword;Finally,the four colors corresponding to Quaternary are filled in the black module of QR code data area to generate color QR code.(2)Color QR code decoding.Decoding is the reverse process of coding,the purpose is to obtain the original information and additional information from the color QR code.The original information is that the backup color QR code is grayed and binarized to get the binarized image,and then the location and correction are carried out through the position detection graphics.The QR code dot matrix is obtained through rasterization,and the original information is obtained by decoding according to the QR code coding rules;The additional information is to find the position of each module and the corresponding color information in the color QR code,and then decode it in reverse according to the coding principle to get the additional information,that is,the information that the color QR code can represent is the original information and the additional information.Based on Visual Studio 2019 platform,this paper designs a color QR code encoding and decoding system.In this paper,the color QR code is generated by the color QR code encoding and decoding system,and the decoding function of the color QR code(4 colors and 8 colors)is tested by the color QR code encoding and decoding system;By using wechat "scan" function to scan,print and download color QR code(4 colors and 8 colors)for QR code decoding test,the recognition accuracy of 4 color QR code is higher than that of 8 color QR code,so choosing 4 colors for filling is the best scheme;By comparing the maximum storage capacity of QR code,4-color QR code and 8-color QR code,in the case of version number 1-L,the maximum storage capacity of 4-color QR code is 1.6 times that of QR code,and the maximum storage capacity of 8-color QR code is 1.9 times that of QR code,which shows that the color QR code encoding and decoding algorithm proposed in this paper significantly increases the storage capacity,improves the information density,and enhances the anti-counterfeiting characteristics.