本书是机器视觉课程的理想教材，作者清晰、系统地阐述了机器视觉的基本概念，介绍理论的基本元素的同时强调算法和实用设计的约束。书中阐述各个主题时，既阐述了基本算法，又介绍了数学工具。此外，本书还使用案例演示具体技术的应用，并阐明设计现实机器视觉系统的关键约束。

本书清晰而系统地阐述了计算机与机器视觉的基本概念，对重要的图像处理和计算机视觉算法进行了详细分析，既介绍理论的基本元素，又强调算法和实际设计约束，并通过实际案例演示具体技术的应用。前三版已经奠定了本书在机器视觉领域中独一无二的地位，这一版进行了全面更新和修订，增加了最新进展，是一部全面而且与时俱进的权威著作。

本书特色
通过丰富的实例和案例研究揭示开发实际视觉系统的来龙去脉，展示了如何在实践中应用这些基本原理。
新增章节包含监视和驾驶辅助系统方面的案例研究，给出了计算机视觉中那些尖端领域应用的实际方法。
对于必要的数学工具和关键理论都进行了详细解释和很好的实例说明。
内容更丰富，覆盖人类虹膜定位、图像拼接、使用RANSAC进行线条检测、性能度量和高光谱成像等主题。
每章的“More Recent Developments”介绍了相关主题的一些新进展。
作者简介
E. R. Davies　著名机器视觉专家、英国物理学会会士、英国机器视觉协会的执行委员，现为伦敦大学皇家霍洛威学院机器视觉荣誉退休教授。Davies教授在图像分析、自动视觉检测和噪声抑制技术等方面有丰富的教学和科研经验。他已发表200余篇论文，出版3部著作。他曾被英国机器视觉协会授予杰出会士奖，并且还是国际模式识别协会的会士。

计算机\人工智能

本书清晰而系统地阐述了计算机与机器视觉的基本概念，对重要的图像处理和计算机视觉算法进行了详细分析，既介绍理论的基本元素，又强调算法和实际设计约束，并通过实际案例演示具体技术的应用。前三版已经奠定了本书在机器视觉领域中独一无二的地位，这一版进行了全面更新和修订，增加了最新进展，是一部全面而且与时俱进的权威著作。
本书特色
 通过丰富的实例和案例研究揭示开发实际视觉系统的来龙去脉，展示了如何在实践中应用这些基本原理。
 新增章节包含监视和驾驶辅助系统方面的案例研究，给出了计算机视觉中那些尖端领域应用的实际方法。
 对于必要的数学工具和关键理论都进行了详细解释和很好的实例说明。
 内容更丰富，覆盖人类虹膜定位、图像拼接、使用RANSAC进行线条检测、性能度量和高光谱成像等主题。
 每章的“More Recent Developments”介绍了相关主题的一些新进展。

（英）E. R. Davies著 伦敦大学：E. R. Davies 著名机器视觉专家、英国物理学会会士、英国机器视觉协会的执行委员，现为伦敦大学皇家霍洛威学院机器视觉荣誉退休教授。Davies教授在图像分析、自动视觉检测和噪声抑制技术等方面有丰富的教学和科研经验。他已发表200余篇论文，出版3部著作。他曾被英国机器视觉协会授予杰出会士奖，并且还是国际模式识别协会的会士。

Contents
Foreword .......................................v
Preface........................................... vii
About the Author ......................... xi
Acknowledgements........................xii
Glossary of Acronyms and Abbreviations ............................. xvi
CHAPTER 1 Vision, the Challenge　.......................... 1
1.1　Introduction—Man and His Senses........................ 1
1.2　The Nature of Vision .................................. 2
1.2.1　The Process of Recognition ......................2
1.2.2　Tackling the Recognition Problem .............................4
1.2.3　Object Location .....................................6
1.2.4　Scene Analysis..........................................8
1.2.5　Vision as Inverse Graphics....................................9
1.3　From Automated Visual Inspection to Surveillance................... 10
1.4　What This Book is About....................................... 12
1.5　The Following Chapters ............................... 13
1.6　Bibliographical Notes ................................... 14
PART　1 LOW-LEVEL VISION 15
CHAPTER 2 Images and Imaging Operations　........................... 17
2.1　Introduction...................................................... 18
2.1.1　Gray Scale Versus Color ....................19
2.2　Image Processing Operations ....................... 23
2.2.1　Some Basic Operations on Grayscale Images ..................24
2.2.2　Basic Operations on Binary Images ...28
2.3　Convolutions and Point Spread Functions ... 32
2.4　Sequential Versus Parallel Operations ......... 34
2.5　Concluding Remarks .................................... 36
2.6　Bibliographical and Historical Notes ........... 36
2.7　Problems ........................... 36
CHAPTER 3 Basic Image Filtering Operations .......................... 38
3.1　Introduction...................................................... 38
3.2　Noise Suppression by Gaussian Smoothing .............. 40
3.3　Median Filters......................................... 43
3.4　Mode Filters................................................ 45
3.5　Rank Order Filters ....................................... 52
3.6 Reducing Computational Load .................. 54
3.7 Sharp　 Unsharp Masking ........................... 55
3.8 Shifts Introduced by Median Filters .......... 56
3.8.1　Continuum Model of Median Shifts................................57
3.8.2　Generalization to Grayscale Images................................59
3.8.3　Problems with Statistics...............................60
3.9 Discrete Model of Median Shifts .............. 62
3.10　Shifts Introduced by Mode Filters ............. 65
3.11　Shifts Introduced by Mean and Gaussian Filters .................
3.12　Shifts Introduced by Rank Order Filters ... 68
3.12.1　Shifts in Rectangular Neighborhoods............................69
3.13　The Role of Filters in Industrial Applications of Vision ......... 74
3.14　Color in Image Filtering ............................ 74
3.15　Concluding Remarks .................................. 76
3.16　Bibliographical and Historical
Notes........................................ 77
3.16.1　More Recent Developments ...........78
3.17　Problems ......................... 79
CHAPTER 4 Thresholding Techniques ......................... 82
4.1 Introduction .................... 83
4.2 Region-Growing Methods....................................... 83
4.3 Thresholding.................................................. 84
4.3.1　Finding a Suitable Threshold ...........85
4.3.2　Tackling the Problem of Bias in Threshold Selection ....86
4.3.3　Summary ...........................................88
4.4　 Adaptive Thresholding ............................... 88
4.4.1　The Chow and Kaneko Approach ...................................91
4.4.2　Local Thresholding Methods ............92
4.5 More Thoroughgoing Approaches to Threshold Selection ...... 93
4.5.1　Variance-Based Thresholding..........................................95
4.5.2　Entropy-Based Thresholding ............96
4.5.3　Maximum Likelihood Thresholding................................97
4.6 The Global Valley Approach to Thresholding ......................... 98
4.7 Practical Results Obtained Using the Global Valley Method.................................. 101
4.8 Histogram Concavity Analysis ................ 106
4.9 Concluding Remarks ................................ 107
4.10　Bibliographical and Historical Notes........................ 108
4.10.1　More Recent Developments .........109
4.11　Problems ....................... 110
CHAPTER 5 Edge Detection .......................................111
5.1 Introduction .................. 112
5.2 Basic Theory of Edge Detection ............. 113
5.3 The Template Matching Approach .......... 115
5.4 Theory of 3 3 3 Template Operators.............. 116
5.5 The Design of Differential Gradient Operators ..................... 117
5.6 The Concept of a Circular Operator ........ 118
5.7 Detailed Implementation of Circular Operators ..................... 120
5.8 The Systematic Design of Differential Edge Operators ........ 122
5.9 Problems with the Above Approach—Some Alternative Schemes.......... 123
5.10　Hysteresis Thresholding ........................... 126
5.11　The Canny Operator ..................................... 128
5.12　The Laplacian Operator ........................... 131
5.13　Active Contours................................ 134
5.14　Practical Results Obtained Using Active Contours................ 137
5.15　The Level Set Approach to Object Segmentation.................. 140
5.16　The Graph Cut Approach to Object Segmentation ................ 141
5.17　Concluding Remarks ................................ 145
5.18　Bibliographical and Historical Notes...................... 146
5.18.1　More Recent Developments .........147
5.19　Problems ....................... 148
CHAPTER 6 Corner and Interest Point Detection .................. 149
6.1 Introduction .................. 150
6.2 Template Matching .................................. 150
6.3 Second-Order Derivative Schemes .......... 151
6.4 A Median Filter-Based Corner Detector ........................153
6.4.1　Analyzing the Operation of the Median Detector ........154
6.4.2　Practical Results .............................156
6.5 The Harris Interest Point Operator .......... 158
6.5.1　Corner Signals and Shifts for Various Geometric Configurations ..........................161
6.5.2　Performance with Crossing Points and Junctions.........162
6.5.3　Different Forms of the Harris Operator ........................165
6.6 Corner Orientation ................................... 166
6.7 Local Invariant Feature Detectors and Descriptors................ 168
6.7.1　Harris Scale and Affine-Invariant Detectors and Descriptors ..................171
6.7.2　Hessian Scale and Affine-Invariant Detectors and Descriptors ......................................173
6.7.3　The SIFT Operator .........................173
6.7.4　The SURF Operator .......................174
6.7.5　Maximally Stable Extremal Regions ............................176
6.7.6　Comparison of the Various Invariant Feature Detectors...............177
6.8　　Concluding Remarks ................................ 180
6.9　　Bibliographical and Historical Notes ....... 181
6.9.1　More Recent Developments ...........184
6.10　Problems ............................................... 184
CHAPTER 7 Mathematical Morphology ......................... 185
7.1 Introduction .................. 185
7.2 Dilation and Erosion in Binary Images ... 186
7.2.1　Dilation and Erosion ......................186
7.2.2　Cancellation Effects .......................186
7.2.3　Modified Dilation and Erosion Operators ....................187
7.3 Mathematical Morphology............................... 187
7.3.1　Generalized Morphological Dilation ............................187
7.3.2　Generalized Morphological Erosion .............................188
7.3.3　Duality Between Dilation and Erosion.........................189
7.3.4　Properties of Dilation and Erosion Operators ..............190
7.3.5　Closing and Opening .....................193
7.3.6　Summary of Basic Morphological Operations .............195
7.4 Grayscale Processing ............................... 197
7.4.1　Morphological Edge Enhancement...............................198
7.4.2　Further Remarks on the Generalization to Grayscale Processing...............199
7.5 Effect of Noise on Morphological Grouping Operations....... 201
7.5.1　Detailed Analysis ...........................203
7.5.2　Discussion ......................................205
7.6 Concluding Remarks ................................ 205
7.7 Bibliographical and Historical Notes ...... 206
7.7.1　More Recent Developments...............................207
7.8 Problem ........................ 208
CHAPTER 8 Texture .............................................. 209
8.1 Introduction ............ 209
8.2 Some Basic Approaches to Texture Analysis ........................ 213
8.3 Graylevel Co-occurrence Matrices .................................... 213
8.4 Laws’ Texture Energy Approach................................ 217
8.5 Ade’s Eigenfilter Approach ............................. 220
8.6 Appraisal of the Laws and Ade Approaches.......................... 221
8.7 Concluding Remarks ................................... 223
8.8 Bibliographical and Historical Notes ................. 223
8.8.1　More Recent Developments..........................................224
PART　2 INTERMEDIATE-LEVEL VISION...................... 227
CHAPTER 9 Binary Shape Analysis　..................................... 229
9.1　　Introduction.................................................... 230
9.2　　Connectedness in Binary Images ............. 230
9.3　　Object Labeling and Counting ................. 231
9.3.1　Solving the Labeling Problem in a More Complex Case....................................235
9.4　　Size Filtering ...................................238
9.5　　Distance Functions and Their Uses ......... 240
9.5.1　Local Maxima and Data Compression .........................243
9.6　　Skeletons and Thinning ............................ 244
9.6.1　Crossing Number ............................247
9.6.2　Parallel and Sequential Implementations of Thinning .248
9.6.3　Guided Thinning............................................251
9.6.4　A Comment on the Nature of the Skeleton ..................251
9.6.5　Skeleton Node Analysis .................251
9.6.6　Application of Skeletons for Shape Recognition .........253
9.7　　Other Measures for Shape Recognition ... 254
9.8　　Boundary Tracking Procedures ................ 257
9.9　　Concluding Remarks ................................ 257
9.10　Bibliographical and Historical Notes........................... 259
9.10.1　More Recent Developments .........260
9.11　Problems ....................... 261
CHAPTER 10 Boundary Pattern Analysis　............................. 266
10.1　　Introduction .......................................266
10.2　　Boundary Tracking Procedures................................ 269
10.3　　Centroidal Profiles......................................269
10.4　　Problems with the Centroidal Profile Approach ................270
10.4.1　Some Solutions ............................271
10.5　　The (s, ψ) Plot ........................................ 274
10.6　　Tackling the Problems of Occlusion ..... 276
10.7　　Accuracy of Boundary Length Measures .......................279
10.8　　Concluding Remarks .............................. 280
10.9　　Bibliographical and Historical Notes........................... 281
10.9.1　More Recent Developments ...............................282
10.10　Problems ..................... 282
CHAPTER 11 Line Detection ...........................................284
11.1 Introduction .........................................284
11.2 Application of the Hough Transform to Line Detection ..... 285
11.3 The Foot-of-Normal Method ................. 288
11.3.1　Application of the Foot-of-Normal Method..............290
11.4 Longitudinal Line Localization ............. 290
11.5 Final Line Fitting ................................... 292
11.6 Using RANSAC for Straight Line Detection....................... 293
11.7 Location of Laparoscopic Tools ............ 297
11.8 Concluding Remarks....................................... 299
11.9 Bibliographical and Historical Notes .... 300
11.9.1　More Recent Developments ......................................301
11.10　Problems ..................... 301
CHAPTER 12 Circle and Ellipse Detection　........................... 303
12.1　　Introduction .....................................304
12.2　　Hough-Based Schemes for Circular Object Detection ......... 305
12.3　　The Problem of Unknown Circle Radius .......................308
12.3.1　Some Practical Results ...............310
12.4　 The Problem of Accurate Center Location ....................311
12.4.1　A Solution Requiring Minimal Computation ............313
12.5　 Overcoming the Speed Problem.......................... 314
12.5.1　More Detailed Estimates of Speed ........................314
12.5.2　Robustness ...................................315
12.5.3　Practical Results ..........................316
12.5.4　Summary....................................................317
12.6　　Ellipse Detection .................................... 320
12.6.1　The Diameter Bisection Method................................320
12.6.2　The Chord　 Tangent Method.....................................322
12.6.3　Finding the Remaining Ellipse Parameters ............... 323
12.7　　Human Iris Location .............................. 325
12.8　　Hole Detection........................................... 327
12.9　　Concluding Remarks .............................. 327
12.10　Bibliographical and Historical Notes .... 328
12.10.1　More Recent Developments.....................................330
12.11　Problems ..................... 331
CHAPTER 13 The Hough Transform and Its Nature ............... 333
13.1　　Introduction ........................................333
13.2　　The Generalized Hough Transform ....... 334
13.3　　Setting Up the Generalized Hough Transform—Some Relevant Questions.............................................336
13.4　　Spatial Matched Filtering in Images........................... 336
13.5　　From Spatial Matched Filters to Generalized Hough Transforms........................... 337
13.6　　Gradient Weighting Versus Uniform Weighting.................. 339
13.6.1　Calculation of Sensitivity and Computational Load ................339
13.7　 Summary ....................................................... 342
13.8　 Use of the GHT for Ellipse Detection .................... 343
13.8.1　Practical Details ....................................347
13.9　　Comparing the Various Methods ........... 349
13.10　Fast Implementations of the Hough Transform ................... 350
13.11　The Approach of Gerig and Klein ......... 352
13.12　Concluding Remarks .............................. 353
13.13　Bibliographical and Historical Notes .... 354
13.13.1　More Recent Developments ....................................356
13.14　Problems ..................... 357
CHAPTER 14 Pattern Matching Techniques ......................... 358
14.1　　Introduction ............................................
359
14.2　　A Graph-Theoretic Approach to Object Location................ 359
14.2.1　A Practical Example—Locating Cream Biscuits ......363
14.3　　Possibilities for Saving Computation .... 366
14.4　　Using the Generalized Hough Transform for Feature Collation ..................... 369
14.4.1　Computational Load ....................370
14.5　 Generalizing the Maximal Clique and Other Approaches .................................... 371
14.6　　Relational Descriptors ............................ 373
14.7　　Search ......................... 376
14.8　　Concluding Remarks .............................. 377
14.9　　Bibliographical and Historical Notes.................................... 378
14.9.1　More Recent Developments.......................................380
14.10　Problems ..................... 381
PART　3 3-D VISION AND MOTION 387
CHAPTER 15 The Three-Dimensional World ......................... 389
15.1　　Introduction ............................................ 389
15.2　　3-D Vision—the Variety of Methods .... 390
15.3　　Projection Schemes for Three-Dimensional Vision ............. 392
15.3.1　Binocular Images ........................393
15.3.2　The Correspondence Problem ....................................396
15.4 Shape from Shading........................................ 398
15.5 Photometric Stereo.......................................... 402
15.6 The Assumption of Surface Smoothness ............................. 405
15.7 Shape from Texture ............................... 407
15.8 Use of Structured Lighting .................... 408
15.9 Three-Dimensional Object Recognition Schemes ............... 410
15.10　Horaud’s Junction Orientation Technique........................411
15.11　An Important Paradigm—Location of Industrial Parts ........ 415
15.12　Concluding Remarks .............................. 417
15.13　Bibliographical and Historical Notes .... 419
15.13.1　More Recent Developments.....................................420
15.14　Problems ..................... 421
CHAPTER 16 Tackling the Perspective n-point Problem　....... 424
16.1 Introduction ........................................424
16.2 The Phenomenon of Perspective Inversion .......................... 425
16.3 Ambiguity of Pose under Weak Perspective Projection ...... 427
16.4 Obtaining Unique Solutions to the Pose Problem ............... 430
16.4.1　Solution of the Three-Point Problem ........................433
16.4.2　Using Symmetric Trapezia for Estimating Pose ......434
16.5 Concluding Remarks............................... 434
16.6 Bibliographical and Historical Notes .... 436
16.6.1　More Recent Developments ......................................437
16.7 Problems.................................................... 438
CHAPTER 17 Invariants and Perspective　............................. 439
17.1　 Introduction.............................................. 440
17.2　 Cross-ratios: the “Ratio of Ratios” Concept ................. 441
17.3　 Invariants for Noncollinear Points ......... 445
17.3.1　Further Remarks About the Five-PointConfiguration..............................................447
17.4　 Invariants for Points on Conics .............. 449
17.5　 Differential and Semi-differential Invariants ........................ 452
17.6　 Symmetric Cross-ratio Functions ........... 454
17.7　 Vanishing Point Detection.................................... 456
17.8　　More on Vanishing Points ..................... 458
17.9　　Apparent Centers of Circles and Ellipses ............................. 460
17.10　The Route to Face Recognition ............. 462
17.10.1　The Face as Part of a 3-D Object ............................464
17.11　Perspective Effects in Art and Photography ........................466
17.12　Concluding Remarks .............................. 472
17.13　Bibliographical and Historical Notes .... 474
17.13.1　More Recent Developments ....................................475
17.14　Problems ..................... 475
CHAPTER 18 Image Transformations and Camera Calibration .. 478
18.1　　Introduction .......................................479
18.2　　Image Transformations .......................... 479
18.3　　Camera Calibration ................................ 483
18.4　　Intrinsic and Extrinsic Parameters ......... 486
18.5　　Correcting for Radial Distortions .......... 488
18.6　　Multiple View Vision.............................. 490
18.7　　Generalized Epipolar Geometry ............ 491
18.8　　The Essential Matrix .............................. 492
18.9　　The Fundamental Matrix................................... 495
18.10　Properties of the Essential and Fundamental Matrices ........ 496
18.11　Estimating the Fundamental Matrix ...... 497
18.12　An Update on the Eight-Point Algorithm ....................497
18.13　Image Rectification ................................ 498
18.14　3-D Reconstruction ................................ 499
18.15　Concluding Remarks .............................. 501
18.16　Bibliographical and Historical Notes .... 502
18.16.1　More Recent Developments ............................503
18.17　Problems ..................... 504
CHAPTER 19 Motion ........................... 505
19.1　　Introduction ................................505
19.2　　Optical Flow ...................................506
19.3　　Interpretation of Optical Flow Fields .... 509
19.4　　Using Focus of Expansion to Avoid Collision ............511
19.5　　Time-to-Adjacency Analysis................................. 513
19.6　　Basic Difficulties with the Optical Flow Model ..............514
19.7　　Stereo from Motion ................................ 515
19.8　　The Kalman Filter .................................. 517
19.9　　Wide Baseline Matching ........................ 519
19.10　Concluding Remarks .............................. 521
19.11　Bibliographical and Historical Notes .... 522
19.12　Problem ...................... 522
PART　4 TOWARD REAL-TIME PATTERN
RECOGNITION SYSTEMS...................... 523
CHAPTER 20 Automated Visual Inspection　.......................... 525
20.1　　Introduction ......................................525
20.2　　The Process of Inspection ...................... 527
20.3　　The Types of Object to be Inspected....................... 527
20.3.1　Food Products .............................528
20.3.2　Precision Components ................528
20.3.3　Differing Requirements for Size Measurement ........529
20.3.4　Three-Dimensional Objects ........530
20.3.5　Other Products and Materials for Inspection ............530
20.4　　Summary: The Main Categories of Inspection..................... 530
20.5　　Shape Deviations Relative to a Standard Template ............. 532
20.6　　Inspection of Circular Products ............. 533
20.7　　Inspection of Printed Circuits ................ 537
20.8　　Steel Strip and Wood Inspection ........... 538
20.9　　Inspection of Products with High Levels of Variability ...... 539
20.10　X-Ray Inspection ................................... 542
20.10.1　The Dual-Energy Approach to X-Ray Inspection ..546
20.11　The Importance of Color in Inspection ....................... 546
20.12　Bringing Inspection to the Factory ........ 548
20.13　Concluding Remarks .............................. 549
20.14　Bibliographical and Historical Notes .... 550
20.14.1　More Recent Developments ....................................552
CHAPTER 21 Inspection of Cereal Grains　............................ 553
21.1　　Introduction ...................................553
21.2　　Case Study: Location of Dark Contaminants in Cereals ..... 554
21.2.1　Application of Morphological and Nonlinear Filters to Locate Rodent Droppings .......................555
21.2.2　Problems with Closing...........................................558
21.2.3　Ergot Detection Using the Global Valley
Method ........................................558
21.3　　Case Study: Location of Insects ............ 560
21.3.1　The Vectorial Strategy for Linear Feature Detection .....................................560
21.3.2　Designing Linear Feature Detection Masks for Larger Windows...................................................563
21.3.3　Application to Cereal Inspection ...............................564
21.3.4　Experimental Results ..................564
21.4　　Case Study: High-Speed Grain Location...............566
21.4.1　Extending an Earlier Sampling Approach.................566
21.4.2　Application to Grain Inspection ................................567
21.4.3　Summary .....................................571
21.5　　Optimizing the Output for Sets of Directional Template Masks ..................................... 572
21.5.1　Application of the Formulae......................................573
21.5.2　Discussion ...................................574
21.6　　Concluding Remarks .............................. 575
21.7　　Bibliographical and Historical Notes.................................... 575
21.7.1　More Recent Developments ......................................576
CHAPTER 22 Surveillance .......................................578
22.1　　Introduction ......................................579
22.2　　Surveillance—The Basic Geometry ...... 580
22.3　　Foreground—Background Separation........................584
22.3.1　Background Modeling ................585
22.3.2　Practical Examples of Background Modeling...........591
22.3.3　Direct Detection of the Foreground ..........................593
22.4　　Particle Filters ........................................ 594
22.5　　Use of Color Histograms for Tracking .. 600
22.6　　Implementation of Particle Filters ......... 604
22.7　　Chamfer Matching, Tracking, and Occlusion ...............607
22.8　　Combining Views from Multiple Cameras ......................609
22.8.1　The Case of Nonoverlapping Fields of View ...........613
22.9　　Applications to the Monitoring of Traffic Flow .............614
22.9.1　The System of Bascle et al. ........614
22.9.2　The System of Koller et al. ........616
22.10　License Plate Location........................................... 619
22.11　Occlusion Classification for Tracking ... 621
22.12　Distinguishing Pedestrians by Their Gait............................. 623
22.13　Human Gait Analysis ............................. 627
22.14　Model-Based Tracking of Animals ....... 629
22.15　Concluding Remarks .............................. 631
22.16　Bibliographical and Historical Notes .... 632
22.16.1　More Recent Developments ....................................634
22.17　Problem ...................... 635
CHAPTER 23 In-Vehicle Vision Systems .............................. 636
23.1　　Introduction ........................................ 637
23.2　　Locating the Roadway ........................... 638
23.3　　Location of Road Markings ................... 640
23.4　　Location of Road Signs.......................................... 641
23.5　　Location of Vehicles .............................. 645
23.6　　Information Obtained by Viewing License Plates and Other Structural Features ....................... 647
23.7　　Locating Pedestrians .............................. 651
23.8　　Guidance and Egomotion ....................... 653
23.8.1　A Simple Path Planning Algorithm...........................656
23.9　　Vehicle Guidance in Agriculture ........... 656
23.9.1　3-D Aspects of the Task .............660
23.9.2　Real-Time Implementation .........661
23.10　Concluding Remarks .............................. 662
23.11　More Detailed Developments and Bibliographies Relating to Advanced Driver Assistance Systems ............... 663
23.11.1　Developments in Vehicle Detection........................664
23.11.2　Developments in Pedestrian Detection ...................666
23.11.3　Developments in Road and Lane Detection............668
23.11.4　Developments in Road Sign Detection ...................669
23.11.5　Developments in Path Planning, Navigation,and Egomotion .........................................................671
23.12 Problem ....................... 671
CHAPTER 24 Statistical Pattern Recognition　....................... 672
24.1　　Introduction ........................................673
24.2　　The Nearest Neighbor Algorithm .......... 674
24.3　　Bayes’ Decision Theory ......................... 676
24.3.1　The Naive Bayes’ Classifier .......678
24.4　　Relation of the Nearest Neighbor and Bayes’Approaches ................................679
24.4.1　Mathematical Statement of the Problem ...................679
24.4.2　The Importance of the Nearest Neighbor Classifier .....................................681
24.5　　The Optimum Number of Features....................................... 681
24.6　　Cost Functions and Error　 Reject Tradeoff.......................... 682
24.7　　The Receiver Operating Characteristic................................. 684
24.7.1　On the Variety of Performance Measures Relating to Error Rates ..............................................686
24.8　　Multiple Classifiers ................................ 688
24.9　　Cluster Analysis ..................................... 691
24.9.1　Supervised and Unsupervised Learning ....................691
24.9.2　Clustering Procedures .................692
24.10　Principal Components Analysis ............. 695
24.11　The Relevance of Probability in Image Analysis ................ 699
24.12　Another Look at Statistical Pattern Recognition: The Support Vector Machine ................................... 700
24.13　Artificial Neural Networks .................... 701
24.14　The Back-Propagation Algorithm......................................... 705
24.15　MLP Architectures ................................. 708
24.16　Overfitting to the Training Data ............ 709
24.17　Concluding Remarks .............................. 712
24.18　Bibliographical and Historical Notes .... 713
24.18.1　More Recent Developments ....................................715
24.19　Problems ..................... 717
CHAPTER 25 Image Acquisition .......................................... 718
25.1　　Introduction ................................718
25.2　　Illumination Schemes ............................. 719
25.2.1　Eliminating Shadows ..................721
25.2.2　Principles for Producing Regions of Uniform Illumination ........................... 724
25.2.3　Case of Two Infinite Parallel Strip Lights ................726
25.2.4　Overview of the Uniform Illumination Scenario ......729
25.2.5　Use of Line-Scan Cameras .........730
25.2.6　Light Emitting Diode (LED) Sources .......................731
25.3　　Cameras and Digitization............................ 732
25.3.1　Digitization.....................................734
25.4　　The Sampling Theorem.......................................... 735
25.5　　Hyperspectral Imaging ........................... 738
25.6　　Concluding Remarks .............................. 739
25.7　　Bibliographical and Historical Notes............................ 740
25.7.1　More Recent Developments ......................................741
CHAPTER 26 Real-Time Hardware and Systems Design
Considerations ............................................... 742
26.1　　Introduction ..........................743
26.2　　Parallel Processing ................................. 744
26.3　　SIMD Systems................................ 745
26.4　　The Gain in Speed Attainable with N Processors ................ 747
26.5　　Flynn’s Classification....................................748
26.6　　Optimal Implementation of Image Analysis Algorithms ..... 75