A practical guide to video and audio compression: from sprockets and rasters to macroblocks

Cliff Wootton9780240806303, 0240806301

Learn all about Codecs – how they work, as well as design and implementation with this comprehensive, easy-to-use guide to compression. After reading this book, you will be able to prepare and distribute professional audio and video on any platform including streamed to the web, broadcast on-air, stored in PVRs, Burned onto CD-ROMs or DVDs, delivered by broadband, or viewed in Kiosk applications, PDA devices, and mobile phones.Key benefits:* Learn from an award-winning technologist for a top media company who knows how to explain codecs in terms you can understand* This entry-level guide contains clear explanations and hundreds of diagrams – no math background needed! Also includes a comprehensive glossary which serves as a useful reference to many technical terms and jargon you will encounter* Learn how to choose the right technique to get the most out of your compression system – saving both storage space and money

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Table of contents :
Table of Contents……Page 6
Preface……Page 10
Acknowledgments……Page 12
1.2 Video Compression Is Like . . …….Page 14
1.3 It’s Not Just About Compressing the Video……Page 15
1.5 The Informed Choice Is Yours……Page 16
1.9 Video Compression Is Not Exactly New……Page 17
1.11 Putting the Salesmen in a Corner……Page 18
1.15 Choosing Your Destination……Page 19
1.18 Working Out the Best Route……Page 20
1.23 Rotate and Wheels-Up……Page 21
1.27 Hitting Some Turbulence on the Way……Page 22
1.30 Conventions……Page 23
1.31 What Did You Call That Codec?……Page 24
1.32 Where to Next?……Page 26
2.2 Compression Is Necessary Because . . …….Page 28
2.5 Spatial Compression……Page 29
2.7 Why Do I Need Video Compression?……Page 31
2.8 Some Real-World Scenarios……Page 32
2.9 Platforms……Page 41
2.10 The Future……Page 46
2.11 On with the Journey……Page 47
3.4 What Sort of User Are You?……Page 48
3.5 Problems You May Encounter……Page 51
3.6 Downsides to Video Compression……Page 53
3.7 Getting Out of the Mire……Page 54
3.9 Moving-Image Formats……Page 55
4.3 How Film Projectors Work……Page 56
4.4 Picture Formats and Sizes……Page 58
4.5 Film Grain and Scanning Resolution……Page 59
4.6 Cinema Formats……Page 62
4.7 Semi-Professional and News-gathering Formats……Page 66
4.8 Home Movie Formats……Page 67
4.9 Audio Synchronization……Page 71
4.10 Magnetic Stripe for Sound Recording……Page 72
4.11 Telecine……Page 73
4.12 Building Your Own Telecine System……Page 77
4.13 Ingest and Restoration……Page 80
4.14 Digital Intermediate Processes……Page 85
4.15 Summary……Page 87
5.2 Video Is Not Film……Page 90
5.4 Frame Rates……Page 91
5.5 Scanning Modes……Page 93
5.6 Interlaced Field Rasters……Page 94
5.8 Picture Sizes and Formats……Page 98
5.9 Aspect Ratio……Page 105
5.10 Analog-to-Digital Conversion……Page 109
5.11 Color Information……Page 118
5.12 Video Formats……Page 124
5.14 Summary……Page 126
6.2 The Power of Convergence……Page 128
6.3 Computer Video Display Standards……Page 129
6.4 Screen Resolution……Page 131
6.5 Video Conferencing Formats……Page 132
6.6 PDA Formats……Page 134
6.7 Mobile Phone Formats……Page 137
6.9 D-Cinema……Page 138
6.11 Dithering to Improve Image Quality……Page 143
6.12 Digital Imaging Processes in the Camera……Page 149
6.13 Color Spaces……Page 150
6.14 High-Dynamic Range Imaging……Page 151
6.16 Summary: All Roads Lead to Rome……Page 158
7.3 Source Audio……Page 160
7.4 How the Audio Is Coded and Synchronized……Page 166
7.6 Source Audio Formats……Page 174
7.7 The New Standards: HE-AAC……Page 176
7.8 Multi-Channel Formats……Page 177
7.9 Pitfalls and Gotchas……Page 180
7.11 Summary: Don’t Tell Harry……Page 181
7.12 Continuing with Our Travels……Page 182
8.2 Not All Codecs Are Created Equal……Page 184
8.3 Why Are Standards So Important?……Page 185
8.4 My Codec Is Better Than Yours……Page 188
8.6 Encoding Tools……Page 191
8.7 Examples of Coded Video to Check Out Online……Page 195
8.16 Conclusions……Page 197
8.17 But How Do They Work?……Page 198
9.2 Video-Compression Technologies……Page 200
9.3 A Short History of Video Compression……Page 201
9.5 Frame Types……Page 202
9.6 Summary……Page 205
10.3 Bit-Stream Structure……Page 208
10.5 The Group of Pictures……Page 209
10.6 Conversion from RGB to Luma and Chroma……Page 212
10.7 Macroblocks……Page 214
10.8 Post-DCT Quantization……Page 220
10.10 Motion-Compensated Coding……Page 224
10.13 The Next Generation……Page 228
11.2 Interlace Tools……Page 230
11.4 Slices……Page 231
11.5 Quantization Improvements……Page 232
11.8 Pan and Scan Support……Page 233
11.9 Aspect Ratio Conversion……Page 234
11.11 Scalable Coding……Page 236
11.12 Systems Layer……Page 237
11.14 Designing a Better Mousetrap……Page 238
12.3 What of Wavelets?……Page 240
12.5 Coding Efficiency Improvements……Page 241
12.6 Shape-Coded Video Applications……Page 242
12.8 Licensing Issues……Page 247
12.9 Summary……Page 248
13.2 Why Do We Need Yet Another Codec?……Page 250
13.3 What’s in a Name?……Page 251
13.5 Performance……Page 252
13.7 Tool Support……Page 253
13.8 Coding Changes……Page 254
13.9 Block-Level Improvements……Page 255
13.10 Issues with GOP Structures, Frames, and Slices……Page 257
13.12 Ongoing Development of the Standard……Page 260
13.14 Risks and Benefits of Adopting H.264……Page 261
13.15 The Output of the Encoder……Page 262
14.2 Producing the Output Bit Stream……Page 264
14.3 Bit-Rate Variability……Page 265
14.6 Flattening Out the Bit Rate (Traffic Shaping)……Page 269
14.7 Joined-Up Systems……Page 272
14.8 The Final Result……Page 274
14.9 Summary of How Encoders Work……Page 275
14.10 The Next Challenge……Page 276
15.2 Streaming Basics……Page 278
15.5 Inserting Additional Data Feeds……Page 279
15.6 Error Correction……Page 280
15.7 Handling Signal Outages……Page 282
15.8 Encoding Latency……Page 284
15.9 Hardware Versus Software……Page 285
15.11 Building Reliable Live-Encoder Farms……Page 287
15.13 Summary: What I’ve Learned About Live Encoding……Page 288
16.3 Basic Concept of Storing Video in Files……Page 290
16.4 File Types……Page 292
16.5 File Formats……Page 294
16.6 MXF Files……Page 302
16.7 ASF Files……Page 303
16.8 File-Related Gotchas……Page 304
16.9 File Management and Life Cycle……Page 306
16.10 Examining File Structures……Page 307
16.11 Solving Problems by Using Compression Tools……Page 310
16.12 Summary of File-Based Video Compression……Page 313
17.3 Grabbing an Analog Feed……Page 314
17.5 Recording Off the Air……Page 315
17.7 Tape Formats and Recording Modes……Page 316
17.9 And Now for Something Completely Different……Page 318
18.2 What Is Digital Rights Management?……Page 320
18.3 Commercial Considerations……Page 322
18.5 Struggles Between Copyright Owners and Pirates……Page 324
18.7 What Rights Do We Need to Protect?……Page 325
18.8 What Is Fair Use?……Page 329
18.11 Where It All Breaks Down……Page 330
18.12 Re-Use……Page 331
18.14 Encryption and Access-Control Techniques……Page 332
18.15 Watermarking Techniques……Page 336
18.16 Patent Pools and Technology Licenses……Page 337