Machine Compatible Script for Fast Text Entry of Text Using Handwriting
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This document is downloaded from DR‑NTU (https://dr.ntu.edu.sg) Nanyang Technological University, Singapore. Machine compatible script for fast text entry of text using handwriting Ma, Yang 2005 Ma, Y. (2005). Machine compatible script for fast text entry of text using handwriting. Doctoral thesis, Nanyang Technological University, Singapore. https://hdl.handle.net/10356/2389 https://doi.org/10.32657/10356/2389 Nanyang Technological University Downloaded on 04 Oct 2021 19:38:41 SGT ATTENTION: The Singapore Copyright Act applies to the use of this document. Nanyang Technological University Library NANYANG TECHNOLOGICAL UNIVERSITY A MACHINE COMPATIBLE SCRIPT FOR FAST ENTRY OF TEXT USING HANDWRITING Ma Yang A thesis submitted to Nanyang Technological University in fulfillment of the requirements for the Degree of Doctor of Philosophy Division of Computing Systems School of Computer Engineering 2005 ATTENTION: The Singapore Copyright Act applies to the use of this document. Nanyang Technological University Library Acknowledgements I am greatly indebted to my supervisor, Prof. Graham Leedham, who is an endless source of enthusiasm, ideas, and patience. It was him who led me into this exciting area of pattern recognition, and has offered me constant encouragement and advice throughout the last three years. I hope I have learned from him not just his broad knowledge, but his insights, inspiration, and his way of conducting research. I gratefully acknowledge Prof. Colin Higgins and his Ph.D student Swe Myo Htwe from Nottingham University. It is a pleasure to work with them on this project. I benefited a lot from discussions with them. Special thanks to Ms Lynn, Gao Hongliang, Lu mingchun, Feng Yunshan, Daisy Chang, Francis chan, Niang Niang Maw, Yang minhua for their time and patience to write evaluation samples for this project. I gratefully acknowledge all my colleagues in the Center of computational intelligence for creating such a pleasant working environment. Particular thanks to Wang xiangrui, Zhu lin, Ma Li, Liu Feng and Chen Fei. It is really wonderful to work with them and talk with them on different issues. My former and present friends, Zhang Yi, Chen Jinmiao, Li Xuhong, helped lighted the atmosphere beyond the work. To all, my heartfelt thanks. I owe deepest appreciation to my parents and my husband who have given me loads of love, happiness and encouragement in the whole journey. This thesis is dedicated to my family for their constant support over all these years. Finally, I would like to thank Nanyang Technological University for offering me this doctoral research opportunity. ATTENTION: The Singapore Copyright Act applies to the use of this document. Nanyang Technological University Library Table of Contents 1. Introduction....................................................................................................................1 1.1 Background................................................................................................................1 1.2 Brief introduction to Pitman and Renqun shorthand .................................................4 1.3 Objectives ..................................................................................................................6 1.4 Contributions .............................................................................................................7 1.5 Thesis Structure .........................................................................................................8 2. Review of related handwriting recognition techniques ............................................10 2.1 Introduction..............................................................................................................10 2.2 On-line Handwriting Recognition ...........................................................................11 2.2.1 Preprocessing....................................................................................................11 2.2.2 External segmentation.......................................................................................13 2.2.3 Character Recognition ......................................................................................15 2.3 Recognition of shorthand.........................................................................................19 2.4 Related methods.......................................................................................................22 2.4.1 Recognition of Korean Characters....................................................................22 2.4.2 Polygonal Approximation.................................................................................24 2.5 Summary..................................................................................................................27 3. System overview...........................................................................................................29 3.1 Geometric Analysis of Pitman Shorthand ...............................................................29 3.2 Geometric Analysis of Renqun shorthand...............................................................32 3.3 Comparison of Renqun and Pitman.........................................................................36 3.4 System structure.......................................................................................................37 3.4.1 Preprocessing....................................................................................................37 3.4.2 Prerequisite .......................................................................................................39 3.4.3 Recognition of Pitman shorthand .....................................................................42 I ATTENTION: The Singapore Copyright Act applies to the use of this document. Nanyang Technological University Library 3.4.4 Recognition of Renqun shorthand ....................................................................43 4. Recognition of the vocalized outline in Pitman shorthand ......................................45 4.1 Recognition of consonant outline ............................................................................45 4.1.1 Segmentation ....................................................................................................46 4.1.2 Classification ....................................................................................................57 4.1.3 Issue of smooth junctions .................................................................................67 4.2 Vowel and diphthong recognition............................................................................69 4.2.1 Classification of symbol type ...........................................................................71 4.2.2 Place-sequence of vowels and diphone.............................................................73 4.3 Evaluation ................................................................................................................75 4.3.1 PSIS System......................................................................................................75 4.3.2 Data Collection .................................................................................................77 4.3.3 Experimental Results ........................................................................................79 4.4 Conclusion ...............................................................................................................86 5. Classification of shortforms in Pitman shorthand....................................................88 5.1 Templates Construction ...........................................................................................88 5.2 Outline Classification ..............................................................................................89 5.2.1 Pre-classification...............................................................................................89 5.2.2 Dissimilarity measure using polar coordinates.................................................90 5.2.3 Hausdorff distance ............................................................................................90 5.3 Evaluation results.....................................................................................................92 5.4 Conclusion ...............................................................................................................97 6. Recognition of Renqun shorthand..............................................................................99 6.1 Rhyme detection ....................................................................................................101 6.2 Consonant classification ........................................................................................104 6.3 Evaluation ..............................................................................................................108 II ATTENTION: The Singapore Copyright Act applies to the use of this document. Nanyang Technological University Library 6.4 Conclusion .............................................................................................................116 7. Discussion, conclusions and recommendations.......................................................118 7.1 A Pitman shorthand online system ........................................................................118 7.2 Evaluation ..............................................................................................................120 7.2.1 Recognition accuracy......................................................................................123