Based On. Net Platform Qr Code Recognition And Applications

Two-dimensional (2D) matrix code is a kind of auto-reading graphics symbol code which takes the image processing technique and the combination coding of computer as the foundation. The efficient and quick identification of 2D-barcode becomes an important research field for its higher information density as present.The thesis mainly analyzes the encoding technique and the decoding technique of the Quick Respond Code (QR-Code). First of all, it gets on from the theory of the encoding system, taking turns to introduce the Linear grouping code, cycling code, BCH code and RS code. It also takes an in-depth research on the RS correct coding, which makes a good theory foundation for the steady circulation of the QR code application system. Secondly, concerning about the digital image processing, the thesis mainly studies the image pre-processing identifying technique. This technique takes use of the Hough transform and the Sobel edge detection arithmetic to locate the coding image, it also uses the space transform to correct the distortion appeared in the image collection, and at the same time it puts forward a weighed neighbor average arithmetic which carries the noise wiping towards histogram. At the process of identifying, it gets out the threshold of the image according to the symmetrical feature of the black and white module for the QR code, which takes the management toward the inputted gray image. Then it gets out the setting of the apex of the horizontal borderline and the vertical borderline using the Sobel edge detection arithmetic and the projective arithmetic. The apex could be used for the partition towards the unit module of the QR code, then gets the corresponding image of each unit module, last the symbol matrix of the identified QR code can be got. Finally, the thesis studies the relative theory of the RS decoding technique; the symbol matrix of the QR code decompounds the letter information contained in the image taking the use of the correct coding. In order to improve the transplanting feature of the encoding and decoding modules of the QR code, the center arithmetic of the QR code is made into the dynamic link libraries to provide the transferring for other processes.Encoding system and decoding system have made the realization on the .NET framework according to the C# language, which is a QR coding image identifying application system with the PC-Camera foundation. Lots of actual tests indicate that either the encoding system could print correctly the QR code image according with the requirement or the decoding system could identify the noisy QR code image correctly during the field of correcting, furthermore, the identifying time of the code could satisfy totally the requirement of the application system.