DOI: 10.3724/SP.J.1249.2018.02151

Journal of Shenzhen University Science and Engineering (深圳大学学报理工版) 2018/35:2 PP.151-157

An improved method of locating L-edges in DataMatrix codes

The traditional localization method based on DataMatrix (DM) code uses the maximum point in the Hough transform domain to locate the ‘L’ shaped edge of DM code. In order to improve the robustness of locating, a new precise feature edge locating method is proposed, which consists of four parts:① the fast location and priority ranking of DM code candidate regions based on corner distribution; ② DM code candidate area contour extraction, which reduces the impact of non-interesting edge on the location; ③ the improved Hough transform, which is used to locate the edge; ④ the iterative weighted least squares method for linear fitting, which is used to locate the ‘L’ line. This method runs on TMS320DM648 platform with a main frequency of 864 MHz. The average recognition time of single barcode is 64 ms for the DM code with a resolution of 640×480 and the recognition rate is 99.9%. The experimental results show that this method can achieve DM code positioning accurately and fast, and it can meet the industrial requirements.

Key words:information processing technology,image processing,DataMatrix code,L feature edge locating,Hough transform,line fitting

ReleaseDate:2018-03-20 15:26:57

[1] 李梅.物联网科技导论[M].北京:北京邮电大学出版社,2015:17-19. LI Mei. Introduction to science and technology[M]. Beijing:Beijing University of Posts and Telecommunications Press, 2015:17-19.(in Chinese)

[2] 胡晓岽,何加铭.Data Matrix码识别技术研究[J].杭州电子科技大学学报,2008,28(5):124-126. HU Xiaodong, HE Jiaming. The technology research of decoding DataMatrix code[J]. Journal of Hangzhou Dianzi University, 2008, 28(5):124-126.(in Chinese)

[3] 王根源,吴祥坤,胡坤,等.DataMatric码的嵌入式识别算法[J].吉林大学学报信息科学版,2016,34(3):419-426. WANG Genyuan, WU Xiangkun, HU Kun, et al. Embedded recognition of DataMatrix code by using cross correlation matching algorithm and Hough transform[J]. Journal of Jilin University Information Science Edition, 2016,34(3):419-426.(in Chinese)

[4] MOSS C, CHAKRABARTI S, SCOTT D W. Parts quality management:direct part marking of data matrix symbol for mission assurance[C]//Aerospace Conference. Big Sky, USA:IEEE, 2013:51-52.

[5] 陈文艺,陈蓓敏.基于复杂背景的二维条码提取技术[J].西安邮电大学学报,2014,19(2):48-51. CHEN Wenyi, CHEN Beimin. Extraction technology of 2-D barcode under complicated background[J]. Journal of Xi'an University of Posts and Telecommunications, 2014, 19(2):48-51.(in Chinese)

[6] 袁远松,赵小敏,杨东勇.DataMatrix条码的畸变校正[J].计算机系统应用,2008(10):47-50. YUAN Yuansong, ZHAO Xiaomin, YANG Dongyong. The correction of DataMatrix barcode distortion[J]. Journal of Xi'an University of Posts and Telecommunications, 2008(10):47-50.(in Chinese)

[7] 王伟,何卫平,雷蕾,等.污染及多视角下DataMatrix码精确定位[J].计算机辅助设计与图形学学报,2013,25(9):1345-1353. WANG Wei, HE Weiping, LEI Lei, et al. Accurate location of polluted DataMatrix code from multiple views[J]. Journal of Computer-Aided Design & Computer Graphics, 2013, 25(9):1345-1353.(in Chinese)

[8] 乔寅骐,肖健华,黄银和,等.基于最小二乘法修正的随机Hough变换直线检测[J].计算机应用,2015,35(11):3312-3315,3320. QIAO Yinqi, XIAO Jianhua, HUANG Yinhe, et al. Randomized Hough transform straight line detection based on least square correction[J]. Journal of Computer Applications, 2015,35(11):3312-3315, 3320.(in Chinese)

[9] 郭斯羽,翟文娟,唐求,等.结合Hough变换与改进最小二乘法的直线检测[J].计算机科学,2012,39(4):196-200. GUO Siyu, ZHAI Wenjuan, TANG Qiu, et al. Combining the Hough transform and an improved least squares method for line detection[J]. Computer Science, 2012, 39(4):196-200.(in Chinese)

[10] WILLIAM A P. Statistical teaching aids[D]. Worcester(USA):Worcester Polytechnic Institute, 2006.

[11] MICHIEL D, ANDREAS C, MIA H, et al. Robustness of reweighted Least Squares Kernel Based Regression[J]. Journal of Multivariate Analysis, 2010, 101(2):447-463

[12] 周乐.基于SUSAN检测算子的二维条码定位方法[J].微型机与应用,2012,31(9):35-37. ZHOU Le. Location method of two-dimensional bar code based on the SUSAN detection operator[J]. Microcomputer & Its Applications, 2012, 31(9):35-37.(in Chinese)

[13] 齐凤山,蒋廷耀.基于Harris的二维码图像角点检测方法改进[J].软件导刊,2016,15(5):199-201. QI Fengshan, JIANG Tingyao. Improvement on 2-D code image corner detection based on Hasrris[J]. Software Guide, 2016,15(5):199-201.(in Chinese)

[14] 郭莉沙,李俊山,朱英宏,等.基于多尺度FAST-9的图像快速匹配算法[J].计算机工程,2012,38(12):208-217. GUO Lisha, LI Junshan, ZHU Yinghong, et al. Fast image matching algorithm based on multi-scale FAST-9[J]. Computer Engineering, 2012, 38(12):208-217.(in Chinese)