From Photon to Pixel: The Digital Camera Handbook

ISBN-13: 9781786301376 / Angielski / Twarda / 2017 / 464 str.

Henri Maitre

Opis

This second edition of the fully revised and updated From Photon to Pixel presents essential elements in modern digital photographic devices. Our universal infatuation with photography profoundly affects its usage and development.
While some sides of photographic -culture- remain wholly unchanged - art photography, journalistic and advertising photography, scientific photography, etc. - new facets emerge: leisure or travel photography, everyday life photography, anecdotal, observational or unusual photography, and microcosm, or micro-community, photography with its culmination in the narcissistic selfie. These new forms combine an often simplified manner of photographing and modern means of instantaneous, remote and mass communication. This book does not extend into the sociological study of photography, instead it explains how the digital camera works by examining in detail each of the components that constitutes it to provide the reader with a preliminary guide into the inner workings of this device.

Spis treści

Acknowledgements xiii

Chapter 1. First Contact  1

1.1. Toward a society of the image  1

1.1.1. A bit of vocabulary in the form of zoology 4

1.1.2. A brief history of photography 7

1.2. The reason for this book 10

1.3. Physical principle of image formation  11

1.3.1. Light  11

1.3.2. Electromagnetic radiation: wave and particle  12

1.3.3. The pinhole 13

1.3.4. From pinholes to photo cameras 15

1.4. Camera block diagram  21

Chapter 2. The Photographic Objective Lens  25

2.1. Focusing  26

2.1.1. From focusing to blurring 26

2.1.2. Focusing complex scenes 28

2.2. Depth of field  34

2.2.1. Long–distance photography  35

2.2.2. Macrophotography  36

2.2.3. Hyperfocal 37

2.3. Angle of view 38

2.3.1. Angle of view and human visual system  38

2.3.2. Angle of view and focal length  39

2.4. Centered systems 41

2.4.1. Of the importance of glasses in lenses  42

2.4.2. Chromatic corrections 45

2.4.3. The choice of an optical system 47

2.4.4. Diaphragms and apertures  50

2.4.5. Zoom  53

2.4.6. Zoom and magnification 54

2.5. Fisheye systems  57

2.5.1. Projection functions  57

2.5.2. Circular and diagonal fisheyes  59

2.5.3. Fisheyes in practice  61

2.6. Diffraction and incoherent light 63

2.6.1. Coherence: incoherence 63

2.6.2. Definitions and notations 65

2.6.3. For a single wavelength  66

2.6.4. Circular diaphragm  68

2.6.5. Discussion 70

2.6.6. Case of a wide spectrum 71

2.6.7. Separation power 73

2.7. Camera calibration 74

2.7.1. Some geometry of image formation 74

2.7.2. Multi–image calibration: bundle adjustment  77

2.7.3. Fisheye camera calibration  78

2.8. Aberrations 79

2.8.1. Chromatic aberration 79

2.8.2. Geometrical aberrations  80

2.8.3. Internal reflections 82

2.8.4. Vignetting 83

2.8.5. The correction of the aberrations 86

Chapter 3. The Digital Sensor  89

3.1. Sensor size 90

3.1.1. Sensor aspect ratio 90

3.1.2. Sensor dimensions 91

3.1.3. Pixel size  93

3.2. The photodetector 93

3.2.1. Image detection materials 93

3.2.2. CCDs  94

3.2.3. CMOSs 97

3.2.4. Back–side illuminated arrangement (BSI), stacked arrangement 101

3.2.5. Stacked arrangements 102

3.2.6. Influence of the choice of technology on noise 103

3.2.7. Conclusion 104

3.3. Integrated filters in the sensor  104

3.3.1. Microlenses  104

3.3.2. Anti–aliasing filters  106

3.3.3. Chromatic selection filters  109

Chapter 4. Radiometry and Photometry 111

4.1. Radiometry: physical parameters  112

4.1.1. Definitions 112

4.1.2. Radiating objects: emissivity and source temperature  116

4.1.3. Industrial lighting sources  122

4.1.4. Reflecting objects: reflectance and radiosity  123

4.2. Subjective aspects: photometry  125

4.2.1. Luminous efficiency curve  126

4.2.2. Photometric quantities  128

4.3. Real systems  128

4.3.1. Etendue 129

4.3.2. Camera photometry  130

4.4. Radiometry and photometry in practice 134

4.4.1. Measurement with a photometer 134

4.4.2. Integrated measurements 137

4.5. From the watt to the ISO 138

4.5.1. ISO sensitivity: definitions  138

4.5.2. Standard output ISO sensitivity SOS  143

4.5.3. Recommended exposure index  143

4.5.4. Exposure value 144

Chapter 5. Color 145

5.1. From electromagnetic radiation to perception 147

5.1.1. The color of objects  147

5.1.2. Color perception  149

5.2. Color spaces  151

5.2.1. The CIE 1931 RGB space  153

5.2.2. Other chromatic spaces  160

5.2.3. The Lab space 162

5.2.4. Other colorimetric spaces 163

5.2.5. TV spaces 164

5.2.6. The sRGB space  165

5.2.7. ICC profile 168

5.2.8. Chromatic thresholds 169

5.3. The white balance 170

5.3.1. Presettings 171

5.3.2. Color calibration  172

5.3.3. Gray test pattern usage  173

5.3.4. Automatic white balance techniques 173

5.3.5. The Retinex model  175

5.4. Acquiring color  178

5.4.1. True color images  181

5.4.2. Chromatic arrays 186

5.4.3. Chromatic selection of the arrays  192

5.5. Reconstructing color: demosaicing 195

5.5.1. Linear interpolation demosaicing  196

5.5.2. Per channel, nonlinear interpolations  199

5.5.3. Interchannel, non–linear interpolations 199

Chapter 6. Image Quality 205

6.1. Qualitative attributes 206

6.1.1. The signal noise ratio 207

6.1.2. Resolution 211

6.1.3. The modulation transfer function  215

6.1.4. Sharpness  221

6.1.5. Acutance  221

6.2. Global image quality assessment 226

6.2.1. Reference–based evaluations 228

6.2.2. No–reference evaluation  230

6.2.3. Perception model evaluation 234

6.3. Information capacity 237

6.3.1. The number of degrees of freedom 238

6.3.2. Entropy 243

6.3.3. Information capacity in photography  245

6.4. What about aesthetics?  252

6.4.1. Birkhoff s measure of beauty 253

6.4.2. Gestalt theory 254

6.4.3. Shannon information theory, Kolmogorov Complexity and Computational Complexity theory  254

6.4.4. Learning aesthetic by machine  254

Chapter 7. Noise in Digital Photography 257

7.1. Photon noise  258

7.1.1. Fluctuations in the optical signal 258

7.1.2. The Poisson hypothesis in practice 261

7.1.3. From photon flux to electrical charge  262

7.2. Electronic noise  265

7.2.1. Dark current  265

7.2.2. Pixel reading noise  266

7.2.3. Crosstalk noise 266

7.2.4. Reset noise 267

7.2.5. Quantization noise 267

7.3. Non–uniform noise 268

7.3.1. Non–uniformity in detectors 268

7.3.2. Salt–and–pepper noise 268

7.3.3. Image reconstruction and compression noise  268

7.4. Noise models for image acquisition 269

7.4.1. Orders of magnitude  270

Chapter 8. Image Representation: Coding and Formats 273

8.1. Native format and metadata  274

8.2. RAW (native) format 275

8.2.1. Contents of the RAW format 278

8.2.2. Advantages of the native format 280

8.2.3. Drawbacks of the native format 281

8.2.4. Standardization of native formats  281

8.3. Metadata  283

8.3.1. The XMP standard  283

8.3.2. The Exif metadata format 284

8.4. Lossless compression formats  286

8.4.1. General lossless coding algorithms 287

8.4.2. Lossless JPEG coding 288

8.5. Image formats for graphic design  289

8.5.1. The PNG format  289

8.5.2. The TIFF format  291

8.5.3. The GIF format  292

8.6. Lossy compression formats  292

8.6.1. JPEG  294

8.6.2. JPEG 2000 299

8.7. Tiled formats  304

8.8. Video coding  305

8.8.1. Video encoding and standardization 306

8.8.2. MPEG coding 307

8.9. Compressed sensing  310

Chapter 9. Elements of Camera Hardware  313

9.1. Image processors 313

9.1.1. Global architecture and functions  314

9.1.2. The central processing unit  315

9.1.3. The digital signal processor 318

9.1.4. The graphics processing unit 320

9.2. Memory 321

9.2.1. Volatile memory  321

9.2.2. Archival memory cards  321

9.3. Screens 327

9.3.1. Two screen types 327

9.3.2. Performance  329

9.3.3. Choice of technology 330

9.4. The shutter 333

9.4.1. Mechanical shutters  333

9.4.2. Electronic shutters 333

9.5. Measuring focus  335

9.5.1. Maximum contrast detection 337

9.5.2. Phase detection  340

9.5.3. Focusing on multiple targets 341

9.5.4. Telemeter configuration and geometry 342

9.5.5. Mechanics of the autofocus system 343

9.5.6. Autofocus in practice 344

9.6. Stabilization  346

9.6.1. Motion sensors 346

9.6.2. Compensating for movement 349

9.6.3. Video stabilization 352

9.7. Additions to the lens assembly: supplementary lenses and filters  353

9.7.1. Focal length adjustment  353

9.7.2. Infra–red filters 356

9.7.3. Attenuation filters 357

9.7.4. Polarizing filters  358

9.7.5. Chromatic filters  365

9.7.6. Colored filters 366

9.7.7. Special effect filters  367

9.8. Power cells 367

9.8.1. Batteries  368

9.8.2. Rechargeable Ni–Cd batteries  368

9.8.3. Lithium–ion batteries 369

Chapter 10. Photographic Software  373

10.1. Integrated software  374

10.1.1. Noise reduction  374

10.1.2. Classic approaches  375

10.1.3. Iterative methods 376

10.1.4. Non–local approaches  377

10.1.5. Facial detection  379

10.1.6. Motion tracking 382

10.1.7. Image rotation  384

10.1.8. Panoramas  385

10.2. Imported software  394

10.2.1. Improving existing functions  395

10.2.2. Creating new functions 395

10.3. External software 397

10.3.1. High–dynamic images (HDR)  397

10.3.2. Plenoptic imaging: improving the depth of field 402

10.3.3. Improving resolution: super–resolution  408

10.3.4. Flutter–shutters  412

Bibliography 417

Index  439