【作者】 袁开心；

【导师】 刘宁钟；

【作者基本信息】 南京航空航天大学 ， 计算机应用技术， 2009， 硕士

【摘要】 随着全球信息化技术的发展,二维条码应运而生,并且具有很好的应用前景。作为二维条码的一种,QR码是建立在数字图像处理技术、组合编码原理等基础上的一种特殊码制。由于二维条码的信息密度比较高,尤其对于QR码,其识别技术比一维条码的识别更为复杂,所以对二维条码有效快速的检测和识别成为当前重要的研究领域。因此,基于数字图像处理的嵌入式条码识别系统及应用的研究无论是在理论上还是在实践中都具有十分重要的意义。本文首先分析了QR码的符号特征、编码理论以及纠错码的应用,探讨了QR码的应用。接着本文研究了图像预处理的算法如灰度化、中值滤波、二值化技术和边缘检测。QR码的检测和识别是QR码应用的关键技术。本文根据QR码的形状特征分析,提出了一种基于链码跟踪的快速有效的QR码检测算法。接下来研究了QR码的旋转算法和矫正算法。之后,探讨了QR码图像的识别和解码算法。实验表明,本文提出的检测和识别算法具有很好的性能,能够快速准确的检测和识别QR码。本文将以上检测、识别和纠错解码一整套算法用C/C++实现,然后设计并实现了一个基于Symbian平台的QR码识别系统,重点分析了Symbian系统的技术特点的S60的应用程序特性,和在Symbian平台上实现本系统所遇到的图像采集、DLL的开发、异常处理、内存泄露以及多线程处理的技术和相应的解决方法。最后,本系统进行了详细的测试,实验表明本系统可以快速检测并识别QR码,具有良好的性能,可以预言QR码在手机上的识别和应用,必将随着3G时代的到来而得到飞速的发展。更多还原

【Abstract】 The 2D barcode emerged with the development of information technology has a promising future.As a kind of 2D barcode, QR Code is a special code based on Digital Image Processing and coding theory. Because 2D barcode has relatively higher density information, its detection and recognition technology is more complex than that of 1D barcode, especially QR Code.Therefore,it is of important theoretical and practical meaning to study the problems of embedded barcode recognition system based on Digital Image Processing.This paper first introduces the QR Code symbol、coding theory and the application of error-correcting codes, and then discussed the application of QR Code. Then we discuss Image Preprocessing, such as gray level transformation, median filter, binarization and edge detection. Detection and Recognition of QR Code is the key technology. Based on the characteristics of the shape of the QR, the algorithm of QR Code’s detection based on chain code tracking has been proposal.Then the paper researches rotation of the QR code and rectification algorithm. At last, the paper discusses the QR Code’s decoding algorithm. Experiments show that the proposed algorithm has good performance, can quickly and accurately detection and identification QR Code.The paper realizes the algorithm of Detection, Recognition and Decoding in C/C++, and designs QR Code decoding system based on the Symbian platform.The paper analysis of the technical characteristics of the Symbian and features of the S60. Then we resolve some key technologies in Symbian Platform, such as capturing image, developing DLL, exception handling and memory leaks and Multi-threaded.Finally, the system has been tested in detail.The experiments prove that the system can quickly detection and identification QR Code with a good performance.The paper predicts the recognition and application of QR Code in the mobile phone is bound to rapid development with the coming of 3G .更多还原