Preface |
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vii | |
List of Figures |
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xiii | |
List of Tables |
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xxiii | |
1 Introduction |
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1 | (12) |
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1.1 Keyword Spotting (KWS) as a Scientific Discipline |
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1 | (5) |
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6 | (1) |
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6 | (2) |
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8 | (2) |
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1.5 Outline and Organisation of the Book |
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10 | (3) |
2 Related Work |
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13 | (28) |
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2.1 A Taxonomy of KWS Systems |
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13 | (4) |
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17 | (3) |
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2.3 Formal Representation |
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20 | (7) |
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2.3.1 Statistical Representation |
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20 | (6) |
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2.3.2 Structural Representation |
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26 | (1) |
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27 | (11) |
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2.4.1 Template-based Approaches for KWS |
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29 | (5) |
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2.4.2 Learning-based Approaches for KWS |
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34 | (4) |
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38 | (3) |
3 Datasets |
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41 | (20) |
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3.1 Historical Manuscripts |
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41 | (4) |
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3.1.1 George Washington (GW) |
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44 | (1) |
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44 | (1) |
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3.1.3 Alvermann Konzilsprotokolle (AK) |
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44 | (1) |
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45 | (1) |
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3.2 Preprocessing the Datasets |
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45 | (13) |
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50 | (2) |
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52 | (1) |
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53 | (1) |
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54 | (1) |
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3.2.5 Morphological Filtering |
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55 | (2) |
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57 | (1) |
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58 | (3) |
4 Graph Representations |
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61 | (22) |
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4.1 Introduction and Basic Definitions |
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61 | (1) |
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4.2 Graph-Based Pattern Recognition |
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62 | (2) |
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4.3 From Handwriting to Graphs |
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64 | (11) |
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4.3.1 Keypoint-Based Graphs |
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65 | (2) |
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67 | (2) |
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4.3.3 Projection-Based Graphs |
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69 | (4) |
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73 | (2) |
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4.4 Preliminary Experimental Evaluation |
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75 | (5) |
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80 | (3) |
5 Graph Matching |
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83 | (28) |
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5.1 Overview and Broader Perspective |
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83 | (1) |
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5.2 Graph Matching for KWS |
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84 | (6) |
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5.2.1 Exact Graph Matching |
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84 | (3) |
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5.2.2 Inexact Graph Matching |
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87 | (2) |
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5.2.3 Formal Requirements |
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89 | (1) |
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90 | (13) |
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5.3.1 Suboptimal Algorithms |
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93 | (1) |
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5.3.2 Bipartite Graph Edit Distance (BP) |
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94 | (3) |
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5.3.3 Hausdorff Edit Distance (HED) |
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97 | (4) |
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5.3.4 Bipartite Graph Edit Distance 2 (BP2) |
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101 | (2) |
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5.4 Polar Graph Dissimilarity (PGD) |
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103 | (5) |
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5.4.1 Polar Segmentation of Graphs |
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104 | (1) |
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5.4.2 Histogram-Based Representation |
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104 | (2) |
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5.4.3 Histogram-Based Dissimilarity Measure |
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106 | (2) |
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108 | (3) |
6 Graph-Based Keyword Spotting |
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111 | (18) |
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6.1 Overview of our Framework for KWS |
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111 | (2) |
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6.2 From Graph Edit Distance (GED) to Retrieval Indices |
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113 | (6) |
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6.2.1 Cost Model for Keyword Spotting |
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113 | (5) |
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118 | (1) |
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6.3 Extensions of the Basic Framework |
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119 | (6) |
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6.3.1 Quadtree Segmentations |
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120 | (2) |
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6.3.2 Fast Rejection Methods |
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122 | (1) |
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123 | (2) |
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125 | (2) |
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127 | (2) |
7 Experiments |
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129 | (70) |
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7.1 Overview of Experimental Evaluation |
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129 | (2) |
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131 | (7) |
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7.2.1 Validation of Parameters |
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132 | (6) |
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7.3 The Baseline KWS System Using BP |
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138 | (3) |
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7.4 Speeding Up the Baseline KWS System |
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141 | (15) |
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7.4.1 KWS System Based on BP with Quadtree Segmentations |
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142 | (4) |
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7.4.2 KWS System Based on BP with Fast Rejection Methods |
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146 | (5) |
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7.4.3 KWS System Based on PGD |
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151 | (5) |
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7.5 KWS System Based on HED |
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156 | (9) |
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7.5.1 Hausdorff Edit Distance |
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156 | (5) |
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7.5.2 Context-aware Hausdorff Edit Distance |
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161 | (4) |
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7.6 KWS System Based on BP2 |
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165 | (4) |
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7.7 Graph-Based Ensembles for KWS |
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169 | (7) |
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7.7.1 Ensemble Methods Based on BP |
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170 | (5) |
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7.7.2 Ensemble Methods Based on HED, CED, and BP2 |
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175 | (1) |
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7.8 Cross-Evaluation of Graph-Based Systems |
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176 | (4) |
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7.9 Quantitative and Qualitative Summary of Graph-Based Systems |
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180 | (9) |
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7.9.1 Quantitative Summary |
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180 | (3) |
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7.9.2 Qualitative Summary |
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183 | (6) |
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7.10 Comparison of Our Framework with Reference Systems |
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189 | (5) |
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189 | (2) |
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7.10.2 Comparison with Template-Based Reference Systems |
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191 | (2) |
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7.10.3 Comparison with Learning-Based Reference Systems |
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193 | (1) |
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194 | (5) |
8 Conclusion & Future Work |
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199 | (8) |
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199 | (5) |
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204 | (3) |
9 Visualisation of Graph Representations |
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207 | (12) |
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209 | (2) |
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211 | (2) |
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213 | (2) |
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215 | (4) |
10 Optimisation of the Parameters |
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219 | (6) |
11 Ensemble Methods |
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225 | (16) |
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11.1 Ensemble Methods Based on HED |
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226 | (4) |
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11.2 Ensemble Methods Based on CED |
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230 | (6) |
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11.3 Ensemble Methods Based on BP2 |
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236 | (5) |
Bibliography |
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241 | (22) |
Index |
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263 | |