Abhay Sharma
UNDERSTANDING COLOR
MANAGEMENT
Second Edition
Understanding Color Management
The Wiley–IS&ampT Series in Imaging Science and Technology
The Society for Imaging Science and Technology is an international society that aims
to advance the science and practices of image assessment. The main objective of the
Wiley–IS&ampT series is to explain the latest scientific and technological developments in
the field of imaging at a professional level. The broad scope of the series focuses on
imaging in all its aspects, with particular emphasis on digital printing, electronic imaging, photofinishing, image preservation, image assessment, image archiving, pre-press
technologies and hybrid imaging systems.
Published
Camera Image Quality ing
by Jonathan B. Phillips, Henrik Eliasson
Color Appearance Models, 3rd Edition
by Mark D. Fairchild
Color in Computer Vision: Fundamentals and Applications
by Theo Gevers, Arjan Gijsenij, Joost van de Weijer, Jan-Mark Geusebroek
Computational Colour Science Using MATLAB, 2nd Edition
by Stephen Westland, Caterina Ripamonti, Vien Cheung
The Art and Science of HDR Imaging
by John J. McCann, Alessandro Rizzi
Measuring Colour, 4th Edition
by R. W. G. Hunt, M. R. Pointer
Fourier Methods in Imaging
by Roger L. Easton Jr.
Color Management : Understanding and Using ICC Profiles
by Phil Green (Editor), Michael Kriss (Series Editor)
The JPEG 2000 Suite
by Peter Schelkens (Editor), Athanassios Skodras (Co-Editor), Touradj Ebrahimi
(Co-Editor)
Digital Color Management: Encoding Solutions, 2nd Edition
by Edward J Giorgianni, Thomas E Madden, Michael Kriss (Series Editor)
Panoramic Imaging: Sensor-Line Cameras and Laser Range-Finders
by Fay Huang, Reinhard Klette, Karsten Scheibe
Color Gamut Mapping
by Ján Morovič
Color Constancy
by Marc Ebner
Colorimetry: Fundamentals and Applications
by Noboru Ohta, Alan Robertson
The Reproduction of Colour, 6th Edition
by R. W. G. Hunt
Understanding Color Management
Abhay Sharma
Ryerson University
Toronto, Canada
Second Edition
This edition first published 2018
© 2018 John Wiley &amp Sons Ltd
Edition History
1e: © 2004 Cengage
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or
transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise,
except as permitted by law. Advice on how to obtain permission to reuse material from this title is available
at http://www.wiley.com/go/permissions.
The right of Abhay Sharma to be identified as the author of this work has been asserted in accordance with
law.
Registered Office(s)
John Wiley &amp Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA
John Wiley &amp Sons Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK
Editorial Office
The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK
For details of our global editorial offices, customer services, and more information about Wiley products
visit us at www.wiley.com.
Wiley also publishes its books in a variety of electronic formats and by print-on-demand. Some content that
appears in standard print versions of this book may not be available in other formats.
Limit of Liability/Disclaimer of Warranty
While the publisher and authors have used their best efforts in preparing this work, they make no
representations or warranties with respect to the accuracy or completeness of the contents of this work and
specifically disclaim all warranties, including without limitation any implied warranties of merchantability or
fitness for a particular purpose. No warranty may be d or extended by sales representatives, written
sales materials or promotional statements for this work. The fact that an organization, website, or product is
referred to in this work as a citation and/or potential source of further information does not mean that the
publisher and authors endorse the information or services the organization, website, or product may provide
or recommendations it may make. This work is sold with the understanding that the publisher is not
engaged in rendering professional services. The advice and strategies contained herein may not be suitable
for your situation. You should consult with a specialist where appropriate. Further, readers should be aware
that websites listed in this work may have changed or disappeared between when this work was written and
when it is read. Neither the publisher nor authors shall be liable for any loss of profit or any other
commercial damages, including but not limited to special, incidental, consequential, or other damages.
Library of Congress Cataloging-in-Publication Data
Names: Sharma, Abhay, author.
Title: Understanding color management / Abhay Sharma, Ryerson University, Toronto, Canada.
Deion: 2nd edition. | Hoboken, NJ : Wiley, [2018] | Series: The Wiley-IS&ampT series in imaging science
and technology | Includes bibliographical references and index. |
Identifiers: LCCN 2018006235 (print) | LCCN 2018006825 (ebook) | ISBN 9781119223733 (pdf ) |
ISBN 9781119223689 (epub) | ISBN 9781119223634 (cloth)
Subjects: LCSH: Color display systems. | Image processing–Digital techniques. | Colorimetry.
Classification: LCC TA1637 (ebook) | LCC TA1637 .S47 2018 (print) | DDC 621.36/7–dc23
LC record available at https://lccn.loc.gov/2018006235
Cover image: © shuoshu/Getty Images
Cover design by Wiley
Set in 10/12pt WarnockPro by Aptara Inc., New Delhi, India
10 9 8 7 6 5 4 3 2 1
Dedicated to my daughter Sasha
Who is the color in my life
vii
Contents
Foreword to nd Edition xv
Foreword to st Edition xvii
Preface xix
Acknowledgments xxvii
1
1.1 Why Do We Need Color Management? 1
1.2 Closed-loop Color Control 3
1.3 Need for an Open System 4
1.4 A Color Management System 5
1.5 Color Management Workflows 8
1.6 ICC – International Color Consortium 10
1.7 RGB and CMYK Color Specification 13
1.8 CIE 1931 Yxy and CIE 1976 L∗ a∗ b∗ 16
1.9 Color Conversions 17
1.10 Three Cs of Color Management 19
1.11 Profile Types 20
1.11.1 Custom Profiles 20
1.11.2 Generic Profiles 21
1.11.3 Standard Profiles 22
1.12 Color Gamuts 24
1.13 Rendering Intents 26
1.14 Color Accuracy 28
1.15 Late-binding Workflows 29
1.16 Spot Colors and Proprietary Systems 30
1.17 Benefits of Color Management 31
1.18 Summary 34
Introduction
Principles of Light and Color 37
2.1 Introduction 37
2.2 Light Source – Object – Human Observer
2.3 Electromagnetic Radiation 39
2.3.1 The Visible Spectrum 39
2.4 Specifying the Light Source 40
2.4.1 Spectral Power Distribution 40
38
viii
Contents
2.5
2.6
2.7
2.8
2.9
2.4.2 Color Temperature 42
2.4.3 CIE Illuminants and Standard Sources 43
2.4.4 Viewing Booths 45
2.4.5 “Warm” and “Cold” Colors 46
Measuring the Sample Spectrum 46
2.5.1 Practical Color Samples 47
Quantifying Human Color Vision 49
2.6.1 CIE Standard Observer 50
2.6.2 Trichromatic Vision 51
Changing the Light Source 53
2.7.1 Chromatic Adaptation 53
2.7.2 Yellow Sodium-Vapor Street Lighting 54
2.7.3 Metamerism – Matching Jacket and Trousers
2.7.4 PANTONE® D50 Lighting Indicator 58
Vision and Measurement 58
2.8.1 Viewing the Invisible – Infrared 59
2.8.2 Ultraviolet Fluorescence 60
2.8.3 Color Illusions 60
2.8.4 Color Appearance Modeling 61
Summary 63
56
Color by Numbers 65
3.1 Introduction 65
3.2 Basic Attributes of Color: Hue, Saturation, and Lightness 66
3.3 Munsell Color System 67
3.4 CIE Color Specification 68
3.5 XYZ Tristimulus Values 69
3.5.1 Calculating XYZ 69
3.5.2 XYZ Example Colors 71
3.5.3 XYZ for Light Sources 72
3.6 CIE 1931 Yxy System 72
3.6.1 Advantages of the Yxy Chromaticity Diagram 74
3.6.2 Disadvantages of the Yxy Chromaticity Diagram 75
3.7 CIE 1976 L∗ a∗ b∗ System 77
3.7.1 L∗ a∗ b∗ Practical Examples 80
3.7.2 L∗ a∗ b∗ vs. Spectral Data 82
3.8 CIE 1976 L∗ C∗ h 83
3.9 Quantifying Color Difference 84
3.9.1 Calculating ΔE 85
3.9.2 Improved ΔE Equations 88
3.9.3 Which ΔE Should I Use? 91
3.9.4 ΔE and Images 92
3.10 Summary 93
Measuring Instruments 95
4.1 Introduction 95
4.2 Instrument Types 96
Contents
4.3
4.4
Instrument Filter Bands 97
Densitometers 98
4.4.1 Density Equation 99
4.4.2 Status Densitometry 99
4.4.3 Density and Process Control 100
4.5 Colorimeters 101
4.5.1 Filter-based Colorimetry 101
4.5.2 Improvements in Display Colorimeters 103
4.6 Spectrophotometers 104
4.6.1 Spectrophotometer Features and Functions 106
4.6.2 Ever Popular X-Rite i1Pro2 109
4.6.3 OBA and UV Fluorescence 110
4.6.4 M0, M1, M2, M3 Measurement Modes 111
4.7 Smartphone and Other Low-cost Systems 114
4.8 Inter-instrument and Inter-model Agreement 115
4.9 Instrument Repeatability vs. Accuracy 116
4.10 Instrument Calibration 117
4.11 Summary 120
121
Introduction 121
ICC Profile Specification 122
Hexadecimal Profile Encoding 123
Structure of an ICC Profile 124
Profile Header 124
5.5.1 Preferred CMM 125
5.5.2 Specification Version 125
5.5.3 Profile Class 126
5.5.4 Data Color Space and PCS 127
5.5.5 Flags 128
5.5.6 Rendering Intent 130
5.5.7 PCS Illuminant 130
5.5.8 Profile Creator 130
Tag Table 131
5.6.1 Profile Deion Tag 131
5.6.2 XYZ Primaries Tag 132
5.6.3 Tone Reproduction Curve Tag 133
5.6.4 Media White Point Tag 133
5.6.5 Chromatic Adaptation Tag 133
5.6.6 Lookup Table Tags 135
5.6.7 Target Tag 137
5.6.8 Gamut Tag 139
5.6.9 Optional Tags 139
5.6.10 Private Tags 140
Version 2 and Version 4 Profiles 140
Version 5 Profiles and iccMAX 141
Inside Profiles
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
ix
x
Contents
5.9 How Does a Lookup Table Work?
5.10 Summary 144
142
Managing Color in Digital Cameras 147
6.1 Introduction 147
6.2 Scanner Profiling 148
6.2.1 Making a Scanner Profile 148
6.3 Paradigm Shift from Scanners to Digital Cameras
6.4 Color Management for a Digital Camera 152
6.4.1 Bayer Color Filter Array 152
6.4.2 In-Camera JPEG Processing 153
6.4.3 Camera RAW Processing 154
6.4.4 Camera RAW Color Management 155
6.4.5 Creating a Camera RAW Profile 157
6.4.6 Digital N
