华南理工大学学报(自然科学版) ›› 2013, Vol. 41 ›› Issue (7): 107-113.doi: 10.3969/j.issn.1000-565X.2013.07.018

• 计算机科学与技术 • 上一篇    下一篇

多笔画联机手写字符识别的动态时间规正算法

Harold Mouchère1 李锦鹏1 Christian Viard- Gaudin1 陈肇欣1,2   

  1. 1.IRCCyN Laboratory,LUNAM Université,Université de Nantes,Nantes 44300,France;2.华南理工大学 电子与信息学院,广东 广州 51064
  • 收稿日期:2013-03-01 出版日期:2013-07-25 发布日期:2013-06-01
  • 通信作者: Harold Mouchère (1981-),男,副教授,主要从事机器学习、联机手写识别、文本分析和联机手写数学表达的研究 E-mail:harold.mouchere@univ- nantes.fr
  • 作者简介:Harold Mouchère (1981-),男,副教授,主要从事机器学习、联机手写识别、文本分析和联机手写数学表达的研究.

A Dynamic Time Warping Algorithm for Recognition of Multi- Stroke On- Line Handwritten Characters

Harold Mouchère1 Li Jin- peng1 Christian Viard- Gaudin1 Chen Zhao- xin1,2   

  1. 1. IRCCyN Laboratory,LUNAM Université,Université de Nantes,Nantes 44300,France; 2.School of Electronic andInformation Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China
  • Received:2013-03-01 Online:2013-07-25 Published:2013-06-01
  • Contact: Harold Mouchère(born in 1981),male,ssociate professor,ainly researches on machine learning,n-line handwritingrecognition,ocument analysis and currently on on-line handwritten math expressions. E-mail:harold.mouchere@univ- nantes.fr
  • About author:Harold Mouchère(born in 1981),male,ssociate professor,ainly researches on machine learning,n-line handwritingrecognition,ocument analysis and currently on on-line handwritten math expressions.

摘要: 在单笔画符号( 或字符) 联机手写识别中,动态时间规正( DTW) 算法遵循时间次序约束和边界约束,并具有较高的识别率.为了将此算法应用于多笔画符号识别,常用而简单的方法是按照人们的手写顺序连接多笔画符号为单笔画符号.但此方法存在一个问题: 人们常使用不同的笔画顺序和笔画方向书写同一个符号,用朴素( Brute Force) 方法寻找所有笔画可能性非常耗时.为了降低计算复杂度, 文中提出了 DTW A *算法.在部分笔画匹配时,此算法保留着次序约束,并用 A * 算法降低计算复杂度. 文中还通过流程图数据库多笔画符号识别实验对比了 DTW A * 算法、DTW 算法、改良Hausdorff 距离3 种算法的性能,结果表明 DTW A *算法具有最高的识别率和最好的稳定性.

关键词: 模式识别, 手写识别, 动态时间规正

Abstract:

Dynamic time warping (DTW) is a famous algorithm to compare two mono- stroke symbols online.It obeys boundary and continuity constraints and possesses high recognition rate.The extension of DTW to multi-stroke symbols raises specific problems.A naive solution is to convert the multi- stroke symbol into a single one via a direct concatenation in the handwriting order.However,people may write a symbol in different stroke di-rections and orders.The application of a brute force method by searching all the possible directions and orders leads to prohibitive calculation times.To reduce the searching complexity,DTW A * algorithm,which keeps the continuity constraint during each partial matching and reduces the searching complexity by using the A * al-gorithm,is proposed and is then tested on a flowchart dataset containing multi- stroke symbols.The results indi-cate that DTW A * algorithm helps to achieve the highest recognition rate and stability,as compared with such two other algorithms as DTW and modified Hausdorff distance.

Key words: pattern recognition, handwriting recognition, dynamic time warping