Computational Colour Science using MATLAB

Presenting a practical, problem-based approach to colour physics, this title describes the key issues encountered in modern colour engineering, including efficient representation of colour information, fourier analysis of reflectance spectra and advanced colorimetric computation. Emphasis is placed on the practical applications rather than the techniques themselves, with material structured around key topics, such as colour calibration of visual displays, computer recipe prediction and models for colour-appearance prediction. Each topic is carefully introduced at three levels to enhance student understanding. Firstly, theoretical ideas and background information are discussed, explanations of mathematical solutions then follow and finally practical solutions are presented using MATLAB. Includes a compendium of equations and numerical data required by the modern colour and imaging scientist. Numerous examples of solutions and algorithms for a wide-range of computational problems in colour science. Provides example scripts using the MATLAB programming language. This text is a must-have for students taking courses in colour science, colour chemistry and colour physics as well as technicians and researchers working in the area. 0470845627 TeamLiB 1 Cover 1 Contents 8 Acknowledgements 12 1.Introduction 14 1.1 Who this book is for 14 1.2 Why base this book upon MATLAB? 15 1.3 A brief review of the CIE system of colorimetry 17 2.Linear Algebra for Beginners 26 2.1 Some basic de . nitions 26 2.2 Solving systems of simultaneous equations 27 2.3 Transposes and inverses 29 2.4 Linear and non- linear transforms 29 3.A Short Introduction to MATLAB 32 3.1 Matrix operations 33 3.2 Computing the transpose and inverse of matrices 35 3.3 M- . les 38 3.4 Using functions in MATLAB 38 4.Computing CIE Tristimulus Values 40 4.1 Introduction 40 4.2 Standard colour- matching functions 40 4.3 Interpolation methods 42 4.4 Extrapolation methods 46 4.5 Tables of weights 47 4.6 Correction for spectral bandpass 48 4.7 Chromaticity diagrams 48 4.8 Implementations and Examples 50 4.8.1 Spectral bandpass correction 50 4.8.2 Reflectance interpolation 52 4.8.3 Computing tristimulus values 54 4.8.4 Plotting the spectral locus 58 5.Computing Colour Di . erence 62 5.1 Introduction 62 5.2 CIELAB and CIELUV colour space 63 5.3 CIELAB colour di . erence 65 5.4 Optimized colour- di . erence formulae 68 5.4.1 CMC( l: c) 68 5.4.2 CIE94 69 5.4.3 CIEDE2000 70 5.5 Implementations and examples 71 5.5.1 Computing CIELAB and CIELUV coordinates 71 5.5.2 Computing colour difference 81 6.Chromatic- adaptation Transforms and Colour Appearance 94 6.1 Introduction 94 6.2 CATs 95 6.2.1 CIECAT94 99 6.2.2 CMCCAT97 102 6.2.3 CMCCAT2000 103 6.3 CAMs 105 6.3.1 CIECAM97s 106 6.3.2 CMCCAM2000 109 6.4 Implementations and examples 109 6.4.1 CATs 109 6.4.2 Computing colour appearance 117 7.Characterization of Computer Displays 124 7.1 Introduction 124 7.2 Gamma 125 7.3 The GOG model 125 7.4 Device- independent transformation 127 7.5 Typical characterization procedure 128 7.6 Implementations and examples 129 8.Characterization of Cameras 140 8.1 Introduction 140 8.2 Correction for non- linearity 141 8.3 Device- independent representation 142 8.4 Implementations and examples 143 9.Characterization of Printers 154 9.1 Introduction 154 9.2 Physical models 155 9.3 Neural networks 156 9.4 Characterization of half- tone printers 158 9.4.1 Correction for non- linearity 158 9.4.2 Device- independent representation 159 9.4.3 The Kubelka ̈C Munk model 160 9.5 Implementations and examples 163 9.5.1 Half- tone printer 163 9.5.2 Continuous- tone printer 168 10.Multispectral Imaging 176 10.1 Introduction 176 10.2 Computational colour constancy and linear models 177 10.3 Surface and illuminant estimation algorithms 183 10.4 Techniques for multispectral imaging 184 10.4.1 The Hardeberg method 184 10.4.2 The Imai and Berns method 185 10.4.3 Methods based on maximum smoothness 185 10.5 Implementations and examples 185 10.5.1 Deriving a set of basis functions 185 10.5.2 Representation of reflectance spectra in a linear model 189 10.5.3 Estimation of reflectance spectra from tristimulus values 192 10.5.4 Estimation of reflectance spectra from camera responses 196 10.5.5 Fourier operations on reflectance spectra 198 11.Colour Toolbox 202 11.1 cband. m ( Box 1) 202 11.2 pinterp. m ( Box 2) 202 11.3 r2xyz. m ( Box 3) 203 11.4 plocus. m ( Box 4) 203 11.5 xyz2lab. m ( Box 5) 203 11.6 lab2xyz. m ( Box 6) 203 11.7 xyz2luv. m ( Box 7) 204 11.8 car2pol. m ( Box 8) 204 11.9 pol2car ( Box 9) 204 11.10 cielabde. m ( Box 10) 204 11.11 dhpolarity ( Box 11) 205 11.12 cmcde. m ( Box 12) 205 11.13 cie94de. m ( Box 13) 205 11.14 cie00de. m ( Box 14) 206 11.15 cmccat97. m ( Box 15) 206 11.16 cmccat00. m ( Box 16) 206 11.17 ciecam97s. m ( Box 17) 207 11.18 gogtest. m ( Box 18) 207 11.19 compgog. m ( Box 19) 208 11.20 rgb2xyz. m ( Box 20) 208 11.21 xyz2rgb. m ( Box 21) 208 11.22 compigog ( Box 22) 208 11.23 getlincam. m ( Box 23) 209 11.24 lincam ( Box 24) 209 11.25 gettrc ( Box 25) 209 11.26 r2xyz ( Box 26) 210 References 212 Index 218 TeamLiB......Page 0 Cover......Page 1 Contents......Page 8 Acknowledgements......Page 12 1.1 Who this book is for......Page 14 1.2 Why base this book upon MATLAB?......Page 15 1.3 A brief review of the CIE system of colorimetry......Page 17 2.1 Some basic de . nitions......Page 26 2.2 Solving systems of simultaneous equations......Page 27 2.4 Linear and non- linear transforms......Page 29 3.A Short Introduction to MATLAB......Page 32 3.1 Matrix operations......Page 33 3.2 Computing the transpose and inverse of matrices......Page 35 3.4 Using functions in MATLAB......Page 38 4.2 Standard colour- matching functions......Page 40 4.3 Interpolation methods......Page 42 4.4 Extrapolation methods......Page 46 4.5 Tables of weights......Page 47 4.7 Chromaticity diagrams......Page 48 4.8.1 Spectral bandpass correction......Page 50 4.8.2 Reflectance interpolation......Page 52 4.8.3 Computing tristimulus values......Page 54 4.8.4 Plotting the spectral locus......Page 58 5.1 Introduction......Page 62 5.2 CIELAB and CIELUV colour space......Page 63 5.3 CIELAB colour di . erence......Page 65 5.4.1 CMC( l: c)......Page 68 5.4.2 CIE94......Page 69 5.4.3 CIEDE2000......Page 70 5.5.1 Computing CIELAB and CIELUV coordinates......Page 71 5.5.2 Computing colour difference......Page 81 6.1 Introduction......Page 94 6.2 CATs......Page 95 6.2.1 CIECAT94......Page 99 6.2.2 CMCCAT97......Page 102 6.2.3 CMCCAT2000......Page 103 6.3 CAMs......Page 105 6.3.1 CIECAM97s......Page 106 6.4.1 CATs......Page 109 6.4.2 Computing colour appearance......Page 117 7.1 Introduction......Page 124 7.3 The GOG model......Page 125 7.4 Device- independent transformation......Page 127 7.5 Typical characterization procedure......Page 128 7.6 Implementations and examples......Page 129 8.1 Introduction......Page 140 8.2 Correction for non- linearity......Page 141 8.3 Device- independent representation......Page 142 8.4 Implementations and examples......Page 143 9.1 Introduction......Page 154 9.2 Physical models......Page 155 9.3 Neural networks......Page 156 9.4.1 Correction for non- linearity......Page 158 9.4.2 Device- independent representation......Page 159 9.4.3 The Kubelka ̈C Munk model......Page 160 9.5.1 Half- tone printer......Page 163 9.5.2 Continuous- tone printer......Page 168 10.1 Introduction......Page 176 10.2 Computational colour constancy and linear models......Page 177 10.3 Surface and illuminant estimation algorithms......Page 183 10.4.1 The Hardeberg method......Page 184 10.5.1 Deriving a set of basis functions......Page 185 10.5.2 Representation of reflectance spectra in a linear model......Page 189 10.5.3 Estimation of reflectance spectra from tristimulus values......Page 192 10.5.4 Estimation of reflectance spectra from camera responses......Page 196 10.5.5 Fourier operations on reflectance spectra......Page 198 11.2 pinterp. m ( Box 2)......Page 202 11.6 lab2xyz. m ( Box 6)......Page 203 11.10 cielabde. m ( Box 10)......Page 204 11.13 cie94de. m ( Box 13)......Page 205 11.16 cmccat00. m ( Box 16)......Page 206 11.18 gogtest. m ( Box 18)......Page 207 11.22 compigog ( Box 22)......Page 208 11.25 gettrc ( Box 25)......Page 209 11.26 r2xyz ( Box 26)......Page 210 References......Page 212 Index......Page 218 Presenting a practical, problem based approach to colour physics, this title describes the key issues encountered in modern colour engineering, including efficient representation of colour information, fourier analysis of reflectance spectra and advanced colorimetric computation. Emphasis is placed on the practical applications rather than the techniques themselves, with material structured around key topics, such as colour calibration of visual displays, computer recipe prediction and models for colour appearance prediction. Each topic is carefully introduced at three levels to enhance student understanding. Firstly, theoretical ideas and background information are discussed, explanations of mathematical solutions then follow and finally practical solutions are presented using MATLAB. It : includes a compendium of equations and numerical data required by the modern colour and imaging scientist; contains numerous examples of solutions and algorithms for a wide range of computational problems in colour science; and, provides example scripts using the MATLAB programming language. This text is a must have for students taking courses in colour science, colour chemistry and colour physics as well as technicians and researchers working in the area An Invaluable Resource For Students Taking Courses In Colour Science, Colour Chemistry And Colour Physics As Well As Technicians And Researchers Working In The Area. This Book Will Also Be A Useful Reference For Professionals And Researchers Working In Related Industries.--book Jacket. Linear Algebra For Beginners -- A Short Introduction To Matlab -- Computing Cie Tristimulus Values -- Computing Colour Difference -- Chromatic-adaptation Transforms And Colour Appearance -- Characterization Of Computer Displays -- Characterization Of Cameras -- Characterization Of Printers -- Multispectral Imaging -- Colour Toolbox. Stephen Westland, Caterina Ripamonti. Includes Bibliographical References (p. [199]-203) And Index. Presenting a problem based approach to colour physics, this title describes various issues encountered in colour engineering, including representation of colour information, fourier analysis of reflectance spectra and colorimetric computation. It discusses topics such as colour calibration of visual displays and computer recipe prediction. "An invaluable resource for students taking courses in colour science, colour chemistry and colour physics as well as technicians and researchers working in the area. This book will also be a useful reference for professionals and researchers working in related industries."--Résumé de l'éditeur