The Art and Science of Digital Compositing (eBook)

Front Cover 1
The Art and Science of Digital Compositing: Techniques for Visual Effects, Animation and Motion Graphics 4
Copyright Page 5
Contents 6
Introduction to the Second Edition 14
Chapter 1 Introduction to Digital Compositing 22
Definition 23
Historical Perspective 24
Terminology 28
Organization of the Book 32
Chapter 2 Learning to See 36
Judging Color, Brightness, and Contrast 37
Light and Shadow 40
The Camera 48
Resolution Limits 48
Focus and Depth of Field 51
Lens Flares and Other Lens Artifacts 53
Motion Blur 60
Depth, Distance, and Perspective 62
Perspective and the Camera 63
Depth Cues 66
Visual "Correctness" 72
Chapter 3 The Digital Representation of Visual Information 74
Image Generation 74
Pixels, Components, and Channels 76
Spatial Resolution 80
Bit Depth 81
Normalized Values 84
Beyond Black and White 85
Floating-point and High Dynamic Range Imagery (HDRI) 92
The HSV Color Representation 95
The YUV Color Representation 98
Image Input Devices 101
Digital Image File Formats 102
File Format Features 103
Variable Bit Depths 103
Different Spatial Resolutions 103
Compression 103
Comment Information in a Header 103
Additional Image Channels 103
Vendor-specific File Format Implementations 104
Compression 104
Run-length Encoding 104
Lossy Compression 107
Chroma Subsampling 108
Image Sequence Compression 111
Choosing a File Format 111
Nonlinear Color Encoding 112
Chapter 4 Basic Image Manipulation 114
Terminology 115
Color Manipulations 118
RGB Multiply 118
Add 119
Gamma Correction 121
Invert 123
Contrast 124
Channel Swapping 127
HSV Manipulations 128
Look-up Table Manipulations 129
Expression Language 131
Spatial Filters 134
Convolves 134
Blurring 137
Sharpen 140
Median Filter 145
Geometric Transformations 146
Panning 147
Rotation 150
Scale 151
3D Transforms 154
Warping 156
Expression Language 159
Filtering Algorithms 160
Motion Blur 165
Chapter 5 Basic Image Compositing 170
Multisource Operators 170
Add 170
Subtract 172
Mix 174
The Matte Image 175
The Integrated Matte Channel 178
Over 179
Additional Operators 181
Multiply 183
Screen 183
Maximum and Minimum 187
In 189
Out 190
Atop 191
Masks 193
Compositing with Premultiplied Images 195
Color Correcting and Combining Premultiplied Images 199
Luminosity and the Image–Matte Relationship 202
Morphing 204
Chapter 6 Matte Creation and Manipulation 210
Rotoscoping 213
Techniques 216
Motion Blur 224
Limitations 227
Procedural Matte Extraction 227
Keying Based on Luminance 228
Keying Based on Chrominance 231
The Color Difference Method 235
Difference Matting 239
Specialized Keying Software 240
Matte Manipulations 243
Checking the Solidity of your Matte 244
Garbage Mattes 244
Edge Mattes 248
Combining Mattes 249
Image Processing on Mattes 249
Chapter 7 Time and Temporal Manipulations 254
Apparent Motion 254
Temporal Resolution 255
Temporal Artifacts 256
Changing the Length or Timing of a Sequence 257
Keyframing 265
Chapter 8 Image Tracking and Stabilization 270
Tracking an Element into a Plate 271
Choosing the Feature to Track 273
Limiting the Search Area 275
Human Intervention 276
Using Tracking Curves Manually 277
Tracking Multiple Points 278
Stabilizing a Plate 279
Camera Tracking 283
Chapter 9 Interface Interactions 284
Workflow 285
The Evolution of Interactivity 287
Methods of Representing the Compositing Process 289
Layer Lists 290
Trees 291
Compressed Branches 294
Timelines 296
Curve Editors 298
Working with Proxy Images 302
Image Viewing and Analysis Tools 303
Image Viewers 304
Pixel or Regional Information Tools 306
Histograms 308
Chapter 10 Film Formats: Media, Resolution, and Aspect Ratios 312
Aspect Ratio 314
Nonsquare Pixels 315
Deciding on a Resolution When You Have an Aspect Ratio 317
Format Conversion Pipeline 318
A Format Conversion Example 320
Film Formats 323
Common 35 mm Formats 324
16 mm Formats 326
Specialized Film Formats 327
Video Formats 329
Fields 329
Color Resolution 332
Gamma 333
Common Video Formats 333
Other Formats 335
Working with Nonsquare Pixels 335
Converting and Combining Formats 340
Converting between Film and Video 344
Chapter 11 Quality and Efficiency 348
Quality 348
Efficiency 349
Production Methodologies 349
Minimizing Data Loss 350
Internal Software Accuracy 354
Consolidating Operations 357
Region of Interest 361
Working in a Networked Environment 362
Disk Usage 362
Precompositing 363
Chapter 12 Creating Elements 366
Lighting 367
Interactive Lighting 369
Matched Cameras 370
The Reference Stand-in 372
Clean Plates 374
Film Stock 374
Filters 377
Choosing a Format 377
Lighting and Shooting with Bluescreens 379
Bluescreen versus Greenscreen 385
Shooting Order 387
Chapter 13 Additional Integration Techniques 388
Scene Continuity 390
Color and Lighting 390
Lighting 391
Light Wrapping 392
Shadows 397
Digital Color Matching 400
Spill Suppression 403
Atmosphere 409
Camera Characteristics 410
Camera Mismatches 410
Camera Movements 414
Scale and Perspective 415
Focus 416
Motion Blur 418
Lens Flares 419
Film Grain and Sensor Noise 420
Chapter 14 Advanced and Related Topics 426
The Digital Representation of Images, Revisited 426
High Dynamic Range Imaging 427
Color Reproduction 435
Working with Limited Bit Depth 438
Conclusions 449
3D Compositing 449
Working with CG Elements 456
Z-Depth Compositing 458
Multi-pass Rendering 469
Related 2D Disciplines 476
Digital Painting 477
Editing 478
The Digital Intermediate 479
Chapter 15 Case Studies 482
James and the Giant Peach 482
Speed 485
Independence Day 487
The Prince of Egypt 491
Budweiser Lizards Commercial 497
Titanic 499
A Gentlemen's Duel 504
Battlestar Galactica 511
Carlton Draught "Big Ad" 515
Chronicles of Narnia: The Lion, the Witch, and the Wardrobe 520
Golden Compass 525
The Incredibles 528
I, Robot 531
King Kong 535
Lost 541
The Lord of the Rings: The Return of the King 545
The Orion Nebula from The Hubble Space Telescope 549
Sin City 557
Sky Captain and the World of Tomorrow 560
Spider-Man 2 568
Underworld: Evolution 575
Wallace and Gromit: The Curse of the Were-Rabbit 582
Star Wars: Episode 3—Revenge of the Sith 588
Breaking Down the Shot—ccm436 589
Creating the Background 591
Creating the Foreground 595
Effects 607
Final Assembly and Reframing 612
Summary 614
Appendix A: Digital Compositing Software: Tools and Features 616
Color Corrections 617
Filters 618
Geometric Transformations and Warps 619
Image Combination 620
Field Controls 621
Matte Generation 621
Timing and Animation 622
Image Generation 622
Tracking 622
Control 623
Other 623
Appendix B: Digital Image File Formats 626
Common Image File Formats 626
The Cineon File Format 627
The OpenExr File Format 633
Using OpenEXR for Visual Effects Production 633
Abstract 633
Floating-point Pixels 634
Compression 635
Open Source 636
How OpenEXR is used at ILM 636
Color Management 636
Why not Cineon/DPX? 637
Real-time Playback 638
References 639
Appendix C: Common Film and Video Formats 640
Film 640
Scanning Resolutions and File Sizes 641
Digital Cinema Projection 645
Video 645
Aspect Ratios 646
Resolutions 646
Interlacing 647
Frame Rates 647
Bibliography 648
Glossary 652
A 652
B 655
C 657
D 661
E 664
F 666
G 669
H 670
I 671
J 672
K 673
L 673
M 675
N 677
O 678
P 679
Q 682
R 682
S 683
T 688
U 691
V 692
W 693
X 694
Y 694
Z 694
Index 696
A 696
B 696
C 696
D 698
E 698
F 699
G 699
H 700
I 700
J 701
K 701
L 701
M 702
N 702
O 702
P 702
Q 703
R 703
S 703
T 704
U 705
V 705
W 705
Y 705
Z 705