This book is a monograph about how to exploit the knowledge of the human color information processing system in order to design usable, ergonomic, and pleasing information displays, entertainment displays, or a highquality visual environment. For the designer of modern selfluminous visual technologies including displays and light sources for general lighting, optimization principles derived from the human visual system are presented. This book has arisen from the need for a specialist text that brings together these principles derived from a comprehensive view of human color information processing from retinal photoreceptors to cogni tion, preference, harmony, and emotions arising in the visual brain with the recent amazing developments of display technology and general indoor light source technology. In this sense, this book is not a textbook on human vision, colorimetry, colorscience,displaytechnology,orlightsourcetechnology.Instead,theemphasisis on how to use the features of the human visual system to meet todays technological challenges including the colorimetric and color appearancebased characterization and calibration of color monitors, color management in digital TV and cinema, optimization of pixel and subpixel architectures for displays of three or more primary colors, color conspicuity, color memory, and color preferencebased enhancement of color displays for visual ergonomics and pleasing image rendering, also concerning cultural and age differences, and last but not least the optimization of spectral power distributions of modern light sources used to illuminate an indoor scene or an image rendering pixel architecture as a backlight.
Peter Bodrogi and Tran Quoc Khanh Illumination, Color and Imaging Wiley-SID Series in Display Technology Series Editor: Anthony C. Lowe Consultant Editor: Michael A. Kriss Display Systems: Design and Applications Lindsay W. MacDonald and Anthony C. Lowe (Eds.) Electronic Display Measurement: Concepts, Techniques, and Instrumentation Peter A. Keller Reflective Liquid Crystal Displays Shin-Tson Wu and Deng-Ke Yang Colour Engineering: Achieving Device Independent Colour Phil Green and Lindsay MacDonald (Eds.) Display Interfaces: Fundamentals and Standards Robert L. Myers Digital Image Display: Algorithms and Implementation Gheorghe Berbecel Flexible Flat Panel Displays Gregory Crawford (Ed.) Polarization Engineering for LCD Projection Michael G. Robinson, Jianmin Chen, and Gary D. Sharp Fundamentals of Liquid Crystal Devices Deng-Ke Yang and Shin-Tson Wu Introduction to Microdisplays David Armitage, Ian Underwood, and Shin-Tson Wu Mobile Displays: Technology and Applications Achintya K. Bhowmik, Zili Li, and Philip Bos (Eds.) Photoalignment of Liquid Crystalline Materials: Physics and Applications Vladimir G. Chigrinov, Vladimir M. Kozenkov and Hoi-Sing Kwok Projection Displays, Second Edition Matthew S. Brennesholtz and Edward H. Stupp Introduction to Flat Panel Displays Jiun-Haw Lee, David N. Liu and Shin-Tson Wu LCD Backlights Shunsuke Kobayashi, Shigeo Mikoshiba and Sungkyoo Lim (Eds.) Liquid Crystal Displays: Addressing Schemes and Electro-Optical Effects, Second Edition Ernst Lueder Transflective Liquid Crystal Displays Zhibing Ge and Shin-Tson Wu Liquid Crystal Displays: Fundamental Physics and Technology Robert H. Chen 3D Displays Ernst Lueder OLED Display Fundamentals and Applications Takatoshi Tsujimura Illumination, Color and Imaging: Evaluation and Optimization of Visual Displays Tran Quoc Khanh and Peter Bodrogi Peter Bodrogi and Tran Quoc Khanh Illumination, Color and Imaging Evaluation and Optimization of Visual Displays The Authors Dr. Peter Bodrogi TU Darmstadt Laboratory of Lighting Technology Darmstadt, Germany bodrogi@lichttechnik.tu-darmstadt.de Prof. Tran Quoc Khanh TU Darmstadt Laboratory of Lighting Technology Darmstadt, Germany khanh@lichttechnik.tu-darmstadt.de The Series Editor Tony Lowe Lambent Consultancy Braishfield, UK lambentconsultants.com All books published by Wiley-VCH are carefully produced. Nevertheless, authors, editors, and publisher do not warrant the information contained in these books, including this book, to be free of errors. Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inadvertently be inaccurate. Library of Congress Card No.: applied for British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. Bibliographic information published by the Deutsche Nationalbibliothek The Deutsche Nationalbibliothek lists this publica- tion in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at http://dnb.d-nb.de. # 2012 Wiley-VCH Verlag & Co. KGaA, Boschstr. 12, 69469 Weinheim, Germany All rights reserved (including those of translation into other languages). No part of this book may be reproduced in any form – by photoprinting, micro- film, or any other means – nor transmitted or trans- lated into a machine language without written permission from the publishers. 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Print ISBN: 978-3-527-41040-8 ePDF ISBN: 978-3-527-65075-0 ePub ISBN: 978-3-527-65074-3 mobi ISBN: 978-3-527-65073-6 oBook ISBN: 978-3-527-65072-9 Cover Design Spieszdesign, Neu-Ulm Typesetting Thomson Digital, Noida, India Printing and Binding Markono Print Media Pte Ltd, Singapore Printed on acid-free paper To Prof. János Schanda, for his research and teaching in the domains of color science, colorimetry, photometry and visual technologies Contents Series Editors Foreword XIII Preface XV About the Authors XXI 1 Color Vision and Self-Luminous Visual Technologies 1 1.1 Color Vision Features and the Optimization of Modern Self-Luminous Visual Technologies 2 1.1.1 From Photoreceptor Structure to Colorimetry 2 1.1.2 Spatial and Temporal Contrast Sensitivity 6 1.1.3 Color Appearance Perception 12 1.1.4 Color Difference Perception 15 1.1.5 Cognitive, Preferred, Harmonic, and Emotional Color 17 1.1.6 Interindividual Variability of Color Vision 18 1.2 Color Vision-Related Technological Features of Modern Self-Luminous (Nonprinting) Visual Technologies 18 1.3 Perceptual, Cognitive, and Emotional Features of the Visual System and the Corresponding Technological Challenge 20 References 23 2 Colorimetric and Color Appearance-Based Characterization of Displays 25 2.1 Characterization Models and Visual Artifacts in General 25 2.1.1 Tone Curve Models and Phosphor Matrices 26 2.1.2 Measured Color Characteristics, sRGB, and Other Characterization Models 27 2.1.3 Additivity and Independence of the Color Channels 35 2.1.4 Multidimensional Phosphor Matrices and Other Methods 35 2.1.5 Spatial Uniformity and Spatial Independence 39 2.1.6 Viewing Direction Uniformity 45 2.1.7 Other Visual Artifacts 46 2.1.8 The Viewing Environment: Viewing Conditions and Modes 48 VII 2.1.9 Application of CIELAB, CIELUV, and CIECAM02 to Self-Luminous Displays 49 2.2 Characterization Models and Visual Artifacts of the Different Display Technologies 51 2.2.1 Modern Applications of the Different Display Technologies 52 2.2.2 Special Characterization Models of the Different Displays 53 2.2.2.1 CRT 53 2.2.2.2 PDP 55 2.2.2.3 Various LCD Technologies and Their Viewing Direction Uniformity 60 2.2.2.4 Head-Mounted Displays and Head-Up Displays 67 2.2.2.5 Projectors Including DMD and LCD 68 2.2.2.6 OLEDs 71 2.3 Display Light Source Technologies 72 2.3.1 Projector Light Sources 73 2.3.2 Backlight Sources 75 2.3.3 Color Filters, Local Dimming, and High Dynamic Range Imaging 79 2.4 Color Appearance of Large Viewing Angle Displays 81 2.4.1 Color Appearance Differences between Small and Large Color Stimuli 81 2.4.1.1 Color Appearance of an Immersive Color Stimulus on a PDP 82 2.4.1.2 Xiao et al.s Experiment on the Appearance of a Self-Luminous 508 Color Stimulus on an LCD 87 2.4.2 Mathematical Modeling of the Color Size Effect 87 References 91 3 Ergonomic, Memory-Based, and Preference-Based Enhancement of Color Displays 97 3.1 Ergonomic Guidelines for Displays 97 3.2 Objectives of Color Image Reproduction 105 3.3 Ergonomic Design of Color Displays: Optimal Use of Chromaticity Contrast 107 3.3.1 Principles of Ergonomic Color Design 107 3.3.2 Legibility, Conspicuity, and Visual Search 108 3.3.3 Chromaticity Contrast for Optimal Search Performance 111 3.3.4 Chromaticity and Luminance Contrast Preference 123 3.4 Long-Term Memory Colors, Intercultural Differences, and Their Use to Evaluate and Improve Color Image Quality 134 3.4.1 Long-Term Memory Colors for Familiar Objects 135 3.4.2 Intercultural Differences of Long-Term Memory Colors 139 3.4.3 Increasing Color Quality by Memory Colors 141 3.5 Color Image Preference for White Point, Local Contrast, Global Contrast, Hue, and Chroma 142 3.5.1 Apparatus and Method to Obtain a Color Image Preference Data Set 143 3.5.2 Image Transforms of Color Image Preference 144 3.5.3 Preferred White Point 144 3.5.4 Preferred Local Contrast 147 VIII Contents 3.5.5 Preferred Global Contrast 147 3.5.6 Preferred Hue and Chroma 150 3.6 Age-Dependent Method for Preference-Based Color Image Enhancement with Color Image Descriptors 151 References 156 4 Color Management and Image Quality Improvement for Cinema Film and TV Production 161 4.1 Workflow in Cinema Film and TV Production Today – Components and Systems 161 4.1.1 Workflow 161 4.1.2 Structure of Color Management in Todays Cinema and TV Technology 164 4.1.3 Color Management Solutions 165 4.2 Components of the Cinema Production Chain 166 4.2.1 Camera Technology in Overview 166 4.2.2 Postproduction Systems 174 4.2.3 CIELAB and CIEDE 2000 Color Difference Formulas Under the Viewing Conditions of TV and Cinema Production 176 4.2.3.1 Procedure of the Visual Experiment 178 4.2.3.2 Experimental Results 181 4.2.4 Applications of the CIECAM02 Color Appearance Model in the Digital Image Processing System for Motion Picture Films 184 4.3 Color Gamut Differences 191 4.4 Exploiting the Spatial–Temporal Characteristics of Color Vision for Digital TV, Cinema, and Camera Development 195 4.4.1 Spatial and Temporal Characteristics in TV and Cinema Production 195 4.4.2 Optimization of the Resolution of Digital Motion Picture Cameras 199 4.4.3 Perceptual and Image Quality Aspects of Compressed Motion Pictures 205 4.4.3.1 Necessity of Motion Picture Compression 205 4.4.3.2 Methods of Image Quality Evaluation 205 4.4.3.3 The Image Quality Experiment 207 4.4.4 Perception-Oriented Development of Watermarking Algorithms for the Protection of Digital Motion Picture Films 214 4.4.4.1 Motivation and Aims of Watermarking Development 214 4.4.4.2 Requirements for Watermarking Technology 216 4.4.4.3 Experiment to Test Watermark Implementations 217 4.5 Optimum Spectral Power Distributions for Cinematographic Light Sources and Their Color Rendering Properties 223 4.6 Visually Evoked Emotions in Color Motion Pictures 229 4.6.1 Technical Parameters, Psychological Factors, and Visually Evoked Emotions 229 4.6.2 Emotional Clusters: Modeling Emotional Strength 231 References 233 Contents IX 5 Pixel Architectures for Displays of Three- and Multi-Color Primaries 237 5.1 Optimization Principles for Three- and Multi-Primary Color Displays to Obtain a Large Color Gamut 238 5.1.1 Target Color Sets 240 5.1.2 Factors of Optimization 244 5.1.2.1 Color Gamut Volume 244 5.1.2.2 Quantization Effi ciency 244 5.1.2.3 Number of Color Primaries 245 5.1.2.4 White Point 245 5.1.2.5 Technological Constraints 246 5.1.2.6 P/W Ratio 247 5.1.2.7 Roundness 249 5.1.2.8 RGB Tone Scales and Display Black Point 250 5.2 Large-Gamut Primary Colors and Their Gamut in Color Appearance Space 250 5.2.1 Optimum Color Primaries 251 5.2.2 Optimum Color Gamuts in Color Appearance Space 252 5.3 Optimization Principles of Subpixel Architectures for Multi-Primary Color Displays 257 5.3.1 The Color Fringe Artifact 258 5.3.2 Optimization Principles 259 5.3.2.1 Minimum Color Fringe Artifact 259 5.3.2.2 Modulation Transfer Function 260 5.3.2.3 Isotropy 260 5.3.2.4 Luminance Resolution 261 5.3.2.5 High Aperture Ratio 261 5.4 Three- and Multi-Primary Subpixel Architectures and Color Image Rendering Methods 262 5.4.1 Three-Primary Architectures 262 5.4.2 Multi-Primary Architectures 264 5.4.3 Color Image Rendering Methods 268 Acknowledgment 270 References 271 6 Improving the Color Quality of Indoor Light Sources 273 6.1 Introduction to Color Rendering and Color Quality 273 6.2 Optimization for Indoor Light Sources to Provide a Visual Environment of High Color Rendering 276 6.2.1 Visual Color Fidelity Experiments 276 6.2.2 Color Rendering Prediction Methods 282 6.2.2.1 Deficits of the Current Color Rendering Index 282 6.2.2.2 Proposals to Redefine the Color Rendering Index 285 6.3 Optimization of Indoor Light Sources to Provide Color Harmony in the Visual Environment 286 6.3.1 Visual Color Harmony Experiments 287 X Contents 6.3.2 Szab et al.s Mathematical Model to Predict Color Harmony 287 6.3.3 A Computational Method to Predict Color Harmony Rendering 289 6.4 Principal Components of Light Source Color Quality 293 6.4.1 Factors Influencing Color Quality 293 6.4.2 Experimental Method to Assess the Properties of Color Quality 296 6.4.3 Modeling Color Quality: Four-Factor Model 302 6.4.4 Principal Components of Color Quality for Three Indoor Light Sources 303 6.5 Assessment of Complex Indoor Scenes Under Different Light Sources 304 6.5.1 Psychological Relationship between Color Difference Scales and Color Rendering Scales 305 6.5.2 Brightness in Complex Indoor Scenes in Association with Color Gamut, Rendering, and Harmony: A Computational Example 311 6.5.3 Whiteness Perception and Light Source Chromaticity 316 6.6 Effect of Interobserver Variability of Color Vision on the Color Quality of Light Sources 318 6.6.1 Variations of Color Vision Mechanisms 319 6.6.2 Effect of Variability on Color Quality 320 6.6.2.1 Variability of the Visual Ratings of Color Quality 321 6.6.2.2 Variability of Perceived Color Differences and the Color Rendering Index 321 6.6.2.3 Variability of Similarity Ratings 322 6.6.3 Relevance of Variability for Light Source Design 324 Acknowledgments 324 References 324 7 Emerging Visual Technologies 329 7.1 Emerging Display Technologies 329 7.1.1 Flexible Displays 329 7.1.2 Laser and LED Displays 330 7.1.3 Color Gamut Extension for Multi-Primary Displays 334 7.2 Emerging Technologies for Indoor Light Sources 339 7.2.1 Tunable LED Lamps for Accent Lighting 339 7.2.2 Optimization for Brightness and Circadian Rhythm 341 7.2.3 Accentuation of Different Aspects of Color Quality 347 7.2.4 Using New Phosphor Blends 348 7.2.5 Implications of Color Constancy for Light Source Design 354 7.3 Summary and Outlook 357 Acknowledgments 360 References 360 Index 363 Contents XI [...]... features of the human visual system to meet todays technological challenges including the colorimetric and color appearance-based characterization and calibration of color monitors, color management in digital TV and cinema, optimization of pixel and subpixel architectures for displays of three or more primary colors, color conspicuity, color memory, and color preference-based enhancement of color displays. .. Features and the Optimization of Modern Self-Luminous Visual Technologies This section summarizes the most important features of color vision for the evaluation and optimization of self-luminous color displays including the photoreceptor structure of the retina, the spatial and temporal contrast sensitivity of the human visual system, color appearance and color difference perception, the components of visual. .. spectral and spatial power distributions of their radiation – without cumbersome and time-consuming direct visual evaluations Illumination, Color and Imaging: Evaluation and Optimization of Visual Displays, First Edition Peter Bodrogi and Tran Quoc Khanh Ó 2012 Wiley-VCH Verlag GmbH & Co KGaA Published 2012 by Wiley-VCH Verlag GmbH & Co KGaA j 1 Color Vision and Self-Luminous Visual Technologies 2 1.1 Color. .. characterization and calibration of color monitors and color management in digital TV and cinema applications However, they also include the less familiar optimization of pixel and subpixel architectures for displays of more than three primary colors, the concepts of color conspicuity, color memory, and color preference-based enhancement of color displays for visual ergonomics and pleasing image rendering... of CIE colorimetry [2] 1.1 Color Vision Features and the Optimization of Modern Self-Luminous Visual Technologies Figure 1.3 Black curves: color matching functions of the CIE 1931 standard colorimetric observer [2]1) denoted by ðlÞ; ðlÞ; ðlÞ x y z intended to describe the matching of color stimuli subtending a visual angle of 1–4 Open gray circles: color matching functions of the CIE 1964 standard... predict the color harmony of different color combinations, and computational methods of color harmony rendering represent an interesting special case of color quality evaluation completed by several other factors of color quality such as perceived brightness, visual clarity, color discrimination capability, and color preference Chapter 6 also shows the result of a principal component analysis of the latter... and emotional color, and the interindividual variability of color vision Specific problems, features, and optimization potentials arising from the characteristics of color vision are described that are relevant for each technology including digital film and TV, cameras, color monitors, head-mounted displays, digital signage displays and large tiled displays, microdisplays, projectors, light sources of. .. appearance of stand-alone color patches, pictorial color images, or combinations of color patches The latter aspect (i.e., esthetic value or preference of color combinations) is called color harmony (Section 6.3) As an example, more or less harmonic combinations of watercolors can be seen in Figure 6.19 Color can also evoke very strong emotions often in combination with other visual and nonvisual factors of. .. three perpendicular axes and certain angles and distances carry psychologically relevant meanings related to the perceived color attributes Hence, these color spaces are very useful tools of color display design and evaluation, including all aspects of color perception, cognition, preference, and emotion For 1.1 Color Vision Features and the Optimization of Modern Self-Luminous Visual Technologies Figure... medium size colors (i.e., below 208) This effect is accounted for by an extension of CIELAB for the specific viewing condition of large self-luminous displays Chapter 3 deals with the ergonomic, memory-based, and preference-based enhancement of color displays Ergonomic guidelines of visual displays and the objectives of color image reproduction are summarized The principles of ergonomic color design . law. Print ISBN: 97 8-3 -5 2 7-4 104 0-8 ePDF ISBN: 97 8-3 -5 2 7-6 507 5-0 ePub ISBN: 97 8-3 -5 2 7-6 507 4-3 mobi ISBN: 97 8-3 -5 2 7-6 507 3-6 oBook ISBN: 97 8-3 -5 2 7-6 507 2-9 Cover Design Spieszdesign, Neu-Ulm Typesetting. Evaluation and Optimization of Visual Displays Tran Quoc Khanh and Peter Bodrogi Peter Bodrogi and Tran Quoc Khanh Illumination, Color and Imaging Evaluation and Optimization of Visual Displays The. power distri- butions of their radiation – without cumbersome and time-consuming direct visual evaluations. Illumination, Color and Imaging: Evaluation and Optimization of Visual Displays, First