Research On Two-dimensional Barcode Dynamic Recognition And Evaluation In The Environment Of Large Scale Logistics

Barcode technology is a kind of automatic recognition technology which integrates coding,printing,identification,data acquisition and processing.Due to fast reading speed,high accuracy and good reliability,barcode has been widely used in logistics,storage,transportation,production automation management and other fields,which occupies an important position in the field of automatic identification.Information contained by 2D barcode is expressed its graphic pattern.Generally,area array CCD or CMOS sensor is used as a means of reading.Therefore,the printing quality of 2D barcode,lighting conditions in current reading environment,imaging capabilities of reading camera and the algorithm applied in the decode process have an important impact on the results of barcode reading and evaluation.As a hot issue,studies on 2D barcode quality in dynamic environment are valuable in practical applications.In this paper,the reading performance of 2D barcode under dynamic environment is studied,base on which a 2D barcode quality evaluation photoelectric system in the environment of logistics is designed.Firstly,the technology and industry background is described in this paper.The feasibility,innovation and practicability of this 2D barcode quality evaluation photoelectric system is proved,in which part QR code reference decoding method and quality evaluation parameters are introduced in detail as an example.Simultaneously,2D barcode detection technology is introduced,including 2D barcode symbol collection and 2D bar code symbol image preprocessing.Secondly,to solve the encountered problems,the 2D barcode quality evaluation photoelectric system is designed based on the hardware including CMOS camera,LED light source and a simulated logistics environment.The software part includes denoising,contrast enhancement,binarization and projection transformation algorithms.The lighting and software performance of this system is tested respectively.The System perform well and successfully accomplish the process of 2D barcode evaluation including symbol contrast,modulation ratio,axial non-uniformity and grid non-uniformity detection.Finally,a direct-linear-transform method is cited to calculate the space position of 2D barcode.For experimental verification,QR code is tested as an example.This space positioning process provides a new reference parameter for 2D barcode quality standardization under logistics environment.