Computational Colour Science Using MATLAB

Stephen Westland was awarded his BSc and PhD from the University of Leeds. In 1986 he joined Courtaulds Research as a Colour Physicist before returning to academia in 1990 to work at the University of Keele. He worked as a post-doctoral researcher and lecturer in the Department of Communication and Neuroscience where he taught and researched colour measurement, human colour vision, computational imaging and image processing. In 1990 he was appointed as a Reader in Colour Imaging at the Colour Imaging Institute of the University of Derby. He was appointed as Professor of Colour Science and Technology in the School of Design at the University of Leeds in 2003 where he currently teaches and researches.He has published more than 100 refereed papers in the areas of colour imaging, colour management, colour physics and colour design. He has been active in professional bodies that are concerned with colour. He is an active participant in conferences organised by the Society of Imaging Society and Technology (IS&T) and served on several organizational and technical committees. In 2008 he was awarded a Fellowship of the Society of Dyers and Colourists and the Davies Medal from the Royal Photographic Society for his research on digital colour imaging.

• AcknowledgementsAbout the Authors1. Introduction 11.1 Preface 11.2 Why Base this Book on MATLAB? 21.3 A Brief Review of the CIE System of Colorimetry 42. Linear Algebra for Beginners 132.1 Some Basic Definitions 132.2 Solving Systems of Simultaneous Equations 142.3 Function Approximation 163. A Short Introduction to MATLAB 193.1 Matrices 193.2 Matrix Operations 213.3 Solving Linear Systems 233.4 M-Files 253.5 Using Functions in MATLAB 254. Computing CIE Tristimulus Values 274.1 Introduction 274.2 Colour-Matching Functions 284.3 Interpolation Methods 294.4 Extrapolation Methods 384.5 Correction for Spectral Bandpass 384.6 Tristimulus Values 394.7 Chromaticity Diagrams 435. CIELAB and Colour Difference 495.1 Introduction 495.2 ACIELAB and CIELUV Colour Space 505.2.1 A Representation of CIELAB Using MATLAB 565.3 CIELAB Colour Difference 605.4 Optimised Colour-Difference Formulae 645.4.1 CMC (l:c) 645.4.2 CIE 94 675.4.3 CIEDE 2000 686. Chromatic-Adaptation Transforms and Colour Appearance 756.1 Introduction 756.2 Chromatic-Adaptation Transforms (CATs) 766.2.1 A Brief History of CATs 806.2.2 CMCCAT97 806.2.3 CMCCAT2000 836.3 Colour-Appearance Models (CAMs) 866.3.1 CIECAM02 887. Physiological Colour Spaces 937.1 Introduction 937.2 Colour Vision 947.3 Cone-Excitation Space 967.4 MacLeod and Boynton Chromaticity Diagram 1017.5 DKL Colour Space 1068. Colour Management 1198.1 The Need for Colour Management 1198.1.1 Using MATLAB to Create Representations of Gamuts 1218.2 RGB Colour Spaces 1228.2.1 sRGB 1238.2.2 Adobe RGB (1998) 1258.3 The International Color Consortium 1268.4 Characterisation and Calibration 1278.4.1 Approaches to Characterisation 1289. Display Characterisation 1319.1 Introduction 1319.2 Gamma 1319.3 The GOG Model 1329.4 Device-Independent Transformation 1339.5 Example Characterisation of CRT Display 1349.6 Beyond CRT Displays 14010. Characterisation of Cameras 14310.1 Introduction 14310.2 Correction for Nonlinearity 14410.3 Correction for Lack of Spatial Uniformity 14610.4 Characterisation 14610.5 Example Characterisation of a Digital Camera 14911. Characterisation of Printers 15911.1 Introduction 15911.1.1 Physical Models 16011.1.2 Neural Networks 16111.2 Characterisation of Half-Tone Printers 16211.2.1 Correction for Nonlinearity 16211.2.2 Neugebauer Models 16311.2.3 Example Characterisation of a Half-Tone Printer 16511.3 Characterisation of Continuous-Tone Printers 16911.3.1 Kubelka-Munk Models 16911.3.2 Interpolation of 3D Look-Up Tables 17211.3.3 General Linear and Nonlinear Transforms 17311.3.4 Example Characterisation of a Half-Tone Printer 17312. Multispectral Imaging 17912.1 Introduction 17912.2 Computational Colour Constancy and Linear Models 18012.2.1 Example Using MATLAB 18112.3 Properties of Reflectance Spectra 18212.3.1 PCA and SVD 18312.3.2 SVD Using MATLAB12.4 Application of SVD to Reflectance Recovery 18912.5 Techniques for Multispectral Imaging 19112.5.1 Maloney-Wandell Method 19112.5.2 Imai-Berns Method 19212.5.3 Shi-Healey Method 19212.5.4 Methods Based on Maximum Smoothness 19312.5.5 Device Characterisation Revisited 19312.5.6 Spectral Recovery Using Low-Dimensional Linear Models in MATLAB 19312.6 Fourier Operations on Reflectance Spectra 193A. Table of White Points of Illuminants used in r2xyz and Other Functions 197B. Colour Toolbox 199B.1 Where to Find the Toolbox 199B.2 How to Install the Toolbox 199B.3 Summary of Toolbox Files 199B.3.1 Computing CIE Tristimulus Values 199B.3.2 CIELAB and Colour Difference 200B.3.3 Chromatic-Adaptation Transforms and ColourAppearance 200B.3.4 Physiological Colour Spaces 200B.3.5 Colour Management 200B.3.6 Display Characterisation 200B.3.7 Characterisation of Cameras 201B.3.8 Characterisation of Printers 201References 203Index 213