| Foreword | 4 |
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| Preface | 6 |
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| 1 Part I: Recognition of Indic Scripts | 9 |
| 2 Part II: Retrieval of Indic Documents | 11 |
| 3 Target Audience | 11 |
| Acknowledgments | 13 |
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| Contents | 14 |
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| Contributors | 16 |
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| Part I Recognition of Indic Scripts | 19 |
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| Building Data Sets for Indian Language OCR Research | 20 |
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| 1 Introduction | 20 |
| 2 Datasets | 21 |
| 2.1 Image Corpus | 21 |
| 2.1.1 Digitization | 22 |
| 2.1.2 Processing and Storage | 22 |
| 2.2 Text Corpus | 23 |
| 2.3 Annotated Data Sets | 23 |
| 3 Annotation | 24 |
| 3.1 Hierarchical Annotation | 26 |
| 3.1.1 Different Levels of Annotation | 26 |
| 3.1.2 Methods of Annotation | 27 |
| 3.2 Annotation Process | 28 |
| 3.2.1 Segmentation | 28 |
| 3.2.2 Components Labeling | 29 |
| 3.2.3 Annotation Tools | 31 |
| 4 Representation and Access | 32 |
| 4.1 Sources of Metainformation | 33 |
| 4.2 Recognizer-Specific Metainformation | 34 |
| 4.3 Digitization Meta Information | 34 |
| 4.4 Annotation Data | 35 |
| 4.4.1 Page Structure Information | 36 |
| 4.4.2 Text Block Structure Information | 36 |
| 4.4.3 Akshara Structure Information | 37 |
| 4.5 Representation Issues | 37 |
| 4.5.1 Complex Layout | 37 |
| 4.5.2 Indian Language Script Issues | 37 |
| 4.6 Data Access | 38 |
| 5 Implementation and Execution | 39 |
| 5.1 Organization of Tasks | 39 |
| 5.2 Status of the Data Sets | 40 |
| 6 Conclusions | 40 |
| References | 41 |
| On OCR of Major Indian Scripts: Bangla and Devanagari | 43 |
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| 1 Introduction | 43 |
| 2 Basic OCR System | 45 |
| 2.1 Group and Individual Character Classifiers | 48 |
| 3 Quantification of Errors | 50 |
| 4 Post-recognition Error Correction | 52 |
| 4.1 Forward--Backward Error Correction Scheme | 53 |
| 5 Discussion | 57 |
| References | 57 |
| A Complete Machine-Printed Gurmukhi OCR System | 59 |
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| 1 Introduction | 59 |
| 2 Characteristics of Gurmukhi Script | 60 |
| 2.1 Character Set | 60 |
| 2.2 Connectivity of Symbols | 60 |
| 2.3 Word Partitioning into Zones | 61 |
| 2.4 Frequently Touching Characters | 62 |
| 2.5 Broken Characters and Headlines | 62 |
| 2.6 Similarity of Group of Symbols | 62 |
| 3 System Overview | 62 |
| 4 Digitization and Pre-processing | 62 |
| 5 Splitting Text into Horizontal Text Strips | 64 |
| 6 Word Segmentation | 67 |
| 7 Sub-division of Strips into Smaller Units | 68 |
| 8 Repairing the Word Shape | 69 |
| 9 Thinning | 70 |
| 10 Repairing Broken Characters | 72 |
| 11 Character Segmentation | 74 |
| 11.1 Touching Characters | 77 |
| 12 Recognition Stage | 78 |
| 12.1 Feature Extraction | 78 |
| 12.2 Classification | 80 |
| 12.2.1 Design of the Binary Tree Classifier | 81 |
| 12.3 Merging Sub-symbols | 81 |
| 13 Post-Processing | 84 |
| 13.1 Check for the Existence of a Word in the Corpus | 84 |
| 13.2 Perform Holistic Recognition of a Word | 84 |
| 14 Experimental Results | 85 |
| 15 Conclusion | 86 |
| References | 87 |
| Progress in Gujarati Document Processing and Character Recognition | 88 |
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| 1 Introduction | 88 |
| 2 Gujarati Script: OCR Perspective | 89 |
| 3 Segmentation | 91 |
| 4 Zone Boundary Identification | 92 |
| 4.1 Using Slopes of the Imaginary Lines Joining Top Left (Bottom Right) Corners | 93 |
| 4.2 Dynamic Programming Approach | 95 |
| 5 Extracting Recognizable Units | 98 |
| 6 Recognition | 98 |
| 6.1 Feature Extraction | 99 |
| 6.1.1 Fringe Map | 100 |
| 6.1.2 Discrete Cosine Transform | 100 |
| 6.1.3 Wavelet Transform | 101 |
| 6.1.4 Zone Information | 102 |
| 6.1.5 Aspect Ratio | 102 |
| 6.2 Classification | 102 |
| 6.2.1 Nearest Neighbor Classifier | 102 |
| 6.2.2 Artificial Neural Networks [ 25 , 26 ] | 103 |
| 6.2.3 Multi-layer Perceptron (MLP) [ 25 ] | 103 |
| 6.2.4 Radial Basis Functions (RBF) networks | 103 |
| 6.2.5 General Regression Neural Network (GRNN) | 104 |
| 6.3 Experimental Setup and Results | 106 |
| 7 Text Generation | 107 |
| 8 Post-processing | 108 |
| 9 Conclusion | 108 |
| References | 109 |
| Design of a Bilingual KannadaEnglish OCR | 111 |
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