Font Size: a A A

Correction Of QR Code Of Quadratic Surface Based On Curve Fitting

Posted on:2018-01-23Degree:MasterType:Thesis
Country:ChinaCandidate:Z Z DingFull Text:PDF
GTID:2348330515979898Subject:Signal and Information Processing
Abstract/Summary:PDF Full Text Request
The 21st century is the information society,it brings people more convenient and efficient way in life.As the visual basis of the human perception of the world,the image is an important means for human to obtain information,to express information and to transmit information,and the two-dimensional barcode such as QR Code,Data Matrix,Aztec code,Maxicode,is widely used in various trades as a symbol which complies with all the above characteristics,as the two-dimensional barcode was developed at the beginning,it was mainly applied in the automotive assembly during the tracking of the auto parts.After more than 20 years,it was extended in various industries.The barcode itself has the characteristics,such as:low cost,high reliability,high security,high error correction capability,editable appearance,is also the main reason for its widespread usage.The QR code in the traditional circulation process belongs to semi-automatic identification,such as the QR code in the supermarket,if the first scan is failed,we can correct the recognition direction to continue to identify,so it is easy to detect the information contained in the symbol.But the industrial production line QR code recognition can not easily change the recognition conditions,so the difficulty of identification is relatively large.The main research object of the thesis is industrial two-dimensional code.In the thesis,we mainly study the basic knowledge of QR Code and the characteristics of the code and the principle of encoding and decoding,and have a detailed understanding of the steps with error correction code in the decoding process.Two-dimensional code image recognition,including image detection,image correction,image location,image extraction and image extractions.Based on the general two-dimensional code pre-processing,the thesis focusing on the following content:(1)For the industrial QR two-dimensional code image acquisition environment is limited,which resulting in two-dimensional code poor quality,such as the background is too dark or too strong exposure,etc.,Adaptive gamma correction method can be used to increase image contrast.(2)For the industrial QR two-dimensional code image's background is complex,and there are more interference factors,the bicubic interpolation(the double three)algorithm is used to distortion-free scaling.(3)In order to solve the problem that the QR two-dimensional code symbol is strongly compress,and the duty cycle is small in the huge picture,according to the two-dimensional QR code symbolic characteristics,auxiliary search is carried out by means of the image template search.(4)The two-dimensional code images collected by the image collection device contain tilt deformation,using intelligent rotation correction method.In the QR code recognition process,the traditional recognition algorithm has good processing effect on the planar image,but the recognition effect is not that good when it is applied to the distorted QR code.In the thesis,a QR code correction algorithm based on curve fitting is proposed,which is based on QR code self-symbol feature-position detection pattern,which can achieve the result of QR code correction by combining the QR code's own symbol characteristics.At last,we.combine the algorithm of classical image preprocessing and the the correction algorithm proposed in the thesis.Using C++ language programming,combined with Google open source library ZXing,we designed the software for many kinds of abnormal environment.Experimental with this software and other software on hundreds of pictures,compared with other identification software,this software recognition rate and recognition time has improved significantly.In view of the general software can not identify the surface QR code,so the surface QR code alone experiment to verify when the image is different in different curvature of the surface,the curve fitting algorithm for image recognition.
Keywords/Search Tags:Industrial QR code, Adaptive Gamma correction, Bicubic Interpolation, Image template matching, Quadratic surface distortions, Curve fitting, ZXing
PDF Full Text Request
Related items