Page 20 -

xviii Contents

Hue and Intensity Histograms 401
Comparing Histograms 402
Requantization 403
Results from Simple Color Features 404
Other Color-Based Methods 407
Grey-Level Image Features 408
Grey Histograms 409
Grey Sigma — Moments 409
Edge Density — Boundaries Between Objects 409
Edge Direction 410
Boolean Edge Density 410
Spatial Considerations 411
Overall Regions 411
Rectangular Regions 412
Angular Regions 412
Circular Regions 414
Hybrid Regions 414
Test of Spatial Sampling 414
Additional Considerations 417
Texture 418
Objects, Contours, Boundaries 418
Data Sets 418
Website Files 419
References 420
Systems 424
Chapter 11 High-Performance Computing for Vision and Image
Processing 425
Paradigms for Multiple-Processor Computation 426
Shared Memory 426
Message Passing 427
Execution Timing 427
Using clock() 428
Using QueryPerformanceCounter 430
The Message-Passing Interface System 432
Installing MPI 432
Using MPI 433
Inter-Process Communication 434
Running MPI Programs 436
Real Image Computations 437
Using a Computer Network — Cluster Computing 440