The CIECAM02 Color Appearance Model
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SpyderX User’s Guide 1 Table of Contents INTRODUCTION 4 WHAT’S IN THE BOX 5 SYSTEM REQUIREMENTS 5 SPYDERX COMPARISON CHART 6 SERIALIZATION AND ACTIVATION 7 SOFTWARE LAYOUT 11 SPYDERX PRO 12 WELCOME SCREEN 12 SELECT DISPLAY 13 DISPLAY TYPE 14 MAKE AND MODEL 15 IDENTIFY CONTROLS 16 DISPLAY TECHNOLOGY 17 CALIBRATION SETTINGS 18 MEASURING ROOM LIGHT 19 CALIBRATION 20 SAVE PROFILE 23 RECAL 24 1-CLICK CALIBRATION 24 CHECKCAL 25 SPYDERPROOF 26 PROFILE OVERVIEW 27 SHORTCUTS 28 DISPLAY ANALYSIS 29 PROFILE MANAGEMENT TOOL 30 SPYDERX ELITE 31 WORKFLOW 31 WELCOME SCREEN 32 SELECT DISPLAY 33 DISPLAY TYPE 34 MAKE AND MODEL 35 IDENTIFY CONTROLS 36 DISPLAY TECHNOLOGY 37 SELECT WORKFLOW 38 STEP-BY-STEP ASSISTANT 39 STUDIOMATCH 41 EXPERT CONSOLE 45 MEASURING ROOM LIGHT 46 CALIBRATION 47 SAVE PROFILE 50 2 RECAL 51 1-CLICK CALIBRATION 51 CHECKCAL 52 SPYDERPROOF 53 SPYDERTUNE 54 PROFILE OVERVIEW 56 SHORTCUTS 57 DISPLAY ANALYSIS 58 SOFTPROOFING/DEVICE SIMULATION 59 PROFILE MANAGEMENT TOOL 60 GLOSSARY OF TERMS 61 FAQ’S 63 INSTRUMENT SPECIFICATIONS 66 Main Company Office: Manufacturing Facility: Datacolor, Inc. Datacolor Suzhou 5 Princess Road 288 Shengpu Road Lawrenceville, NJ 08648 Suzhou, Jiangsu P.R. China 215021 3 Introduction Thank you for purchasing your new SpyderX monitor calibrator. This document will offer a step-by-step guide for using your SpyderX calibrator to get the most accurate color from your laptop and/or desktop display(s). 4 What’s in the Box • SpyderX Sensor • Serial Number • Welcome Card with Welcome page details • Link to download the -
Applying CIECAM02 for Mobile Display Viewing Conditions
Applying CIECAM02 for Mobile Display Viewing Conditions YungKyung Park*, ChangJun Li*, M. R. Luo*, Youngshin Kwak**, Du-Sik Park **, and Changyeong Kim**; * University of Leeds, Colour Imaging Lab, UK*, ** Samsung Advanced Institute of Technology, Yongin, South Korea** Abstract Small displays are widely used for mobile phones, PDA and 0.7 Portable DVD players. They are small to be carried around and 0.6 viewed under various surround conditions. An experiment was carried out to accumulate colour appearance data on a 2 inch 0.5 mobile phone display, a 4 inch PDA display and a 7 inch LCD 0.4 display using the magnitude estimation method. It was divided into v' 12 experimental phases according to four surround conditions 0.3 (dark, dim, average, and bright). The visual results in terms of 0.2 lightness, colourfulness, brightness and hue from different phases were used to test and refine the CIE colour appearance model, 0.1 CIECAM02 [1]. The refined model is based on continuous 0 functions to calculate different surround parameters for mobile 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 displays. There was a large improvement of the model u' performance, especially for bright surround condition. Figure 1. The colour gamut of the three displays studied. Introduction Many previous colour appearance studies were carried out using household TV or PC displays viewed under rather restricted viewing conditions. In practice, the colour appearance of mobile displays is affected by a variety of viewing conditions. First of all, the display size is much smaller than the other displays as it is built to be carried around easily. -
Prediction of Munsell Appearance Scales Using Various Color-Appearance Models
Prediction of Munsell Appearance Scales Using Various Color- Appearance Models David R. Wyble,* Mark D. Fairchild Munsell Color Science Laboratory, Rochester Institute of Technology, 54 Lomb Memorial Dr., Rochester, New York 14623-5605 Received 1 April 1999; accepted 10 July 1999 Abstract: The chromaticities of the Munsell Renotation predict the color of the objects accurately in these examples, Dataset were applied to eight color-appearance models. a color-appearance model is required. Modern color-appear- Models used were: CIELAB, Hunt, Nayatani, RLAB, LLAB, ance models should, therefore, be able to account for CIECAM97s, ZLAB, and IPT. Models were used to predict changes in illumination, surround, observer state of adapta- three appearance correlates of lightness, chroma, and hue. tion, and, in some cases, media changes. This definition is Model output of these appearance correlates were evalu- slightly relaxed for the purposes of this article, so simpler ated for their uniformity, in light of the constant perceptual models such as CIELAB can be included in the analysis. nature of the Munsell Renotation data. Some background is This study compares several modern color-appearance provided on the experimental derivation of the Renotation models with respect to their ability to predict uniformly the Data, including the specific tasks performed by observers to dimensions (appearance scales) of the Munsell Renotation evaluate a sample hue leaf for chroma uniformity. No par- Data,1 hereafter referred to as the Munsell data. Input to all ticular model excelled at all metrics. In general, as might be models is the chromaticities of the Munsell data, and is expected, models derived from the Munsell System per- more fully described below. -
Computational Color Harmony Based on Coloroid System
Computational Aesthetics in Graphics, Visualization and Imaging (2005) L. Neumann, M. Sbert, B. Gooch, W. Purgathofer (Editors) Computational Color Harmony based on Coloroid System László Neumanny, Antal Nemcsicsz, and Attila Neumannx yGrup de Gràfics de Girona, Universitat de Girona, and Institució Catalana de Recerca i Estudis Avançats, ICREA, Barcelona, Spain zBudapest University of Technology and Economics, Hungary xInstitute of Computer Graphics and Algorithms, Vienna University of Technology, Austria [email protected], [email protected], [email protected] (a) (b) Figure 1: (a) visualization of the overall appearance of a dichromatic color set with `caleidoscope' option of the Color Plan Designer software and (b) interactive color selection of a dichromatic color set in multi-layer mode, applying rotated regular grid. Abstract This paper presents experimentally based rules and methods for the creation of harmonic color sets. First, dichro- matic rules are presented which concern the harmony relationships of two hues. For an arbitrarily given hue pair, we define the just harmonic saturation values, resulting in minimally harmonic color pairs. These values express the fuzzy border between harmony and disharmony regions using a single scalar. Second, the value of harmony is defined corresponding to the contrast of lightness, i.e. the difference of perceptual lightness values. Third, we formulate the harmony value of the saturation contrast, depending on hue and lightness. The results of these investigations form a basis for a unified, coherent dichromatic harmony formula as well as for analysis of polychromatic color harmony. Introduced color harmony rules are based on Coloroid, which is one of the 5 6 main color-order systems and − furthermore it is an aesthetically uniform continuous color space. -
Specification of Srgb
How to interpret the sRGB color space (specified in IEC 61966-2-1) for ICC profiles A. Key sRGB color space specifications (see IEC 61966-2-1 https://webstore.iec.ch/publication/6168 for more information). 1. Chromaticity co-ordinates of primaries: R: x = 0.64, y = 0.33, z = 0.03; G: x = 0.30, y = 0.60, z = 0.10; B: x = 0.15, y = 0.06, z = 0.79. Note: These are defined in ITU-R BT.709 (the television standard for HDTV capture). 2. Reference display‘Gamma’: Approximately 2.2 (see precise specification of color component transfer function below). 3. Reference display white point chromaticity: x = 0.3127, y = 0.3290, z = 0.3583 (equivalent to the chromaticity of CIE Illuminant D65). 4. Reference display white point luminance: 80 cd/m2 (includes veiling glare). Note: The reference display white point tristimulus values are: Xabs = 76.04, Yabs = 80, Zabs = 87.12. 5. Reference veiling glare luminance: 0.2 cd/m2 (this is the reference viewer-observed black point luminance). Note: The reference viewer-observed black point tristimulus values are assumed to be: Xabs = 0.1901, Yabs = 0.2, Zabs = 0.2178. These values are not specified in IEC 61966-2-1, and are an additional interpretation provided in this document. 6. Tristimulus value normalization: The CIE 1931 XYZ values are scaled from 0.0 to 1.0. Note: The following scaling equations can be used. These equations are not provided in IEC 61966-2-1, and are an additional interpretation provided in this document. 76.04 X abs 0.1901 XN = = 0.0125313 (Xabs – 0.1901) 80 76.04 0.1901 Yabs 0.2 YN = = 0.0125313 (Yabs – 0.2) 80 0.2 87.12 Zabs 0.2178 ZN = = 0.0125313 (Zabs – 0.2178) 80 87.12 0.2178 7. -
Analysis of White Point and Phosphor Set Differences of CRT Displays
Peter G. Engeldrum Imcotek, Inc. P.O. Box 66 Bloomfield, CT 06002 John L. lngraham Billerica, MA 01821 Analysis of White Point and Phosphor Set Differences of CRT Displays There are a variety of CRT phosphor sets used to display the CRT screen; so called WYSIWYG (what you see is color information. In addition, the white point, achieved what you get) color. To attain this result we require an when the red, green, and blue phosphors are excited by unambiguous description of color on the CRT. The CIE beam currents corresponding to the maximum digital count system of calorimetry provides for this description in terms for each primary, is not standardized. Displaying a file of CIE tristimulus values X, Y, Z. containing RGB digital values on unlike monitors, with dif- For calorimetry to be useful, there are additional quan- ferent phosphors andlor white points, would produce dif- tities that need to be specified. First we need to know the ferent colors. Computer stimulations were conducted to “white point”; that is the tristimulus values of the white on compute the colors for CRTs with di#erent phosphor sets the screen when the luminance output of the three phosphors and constant white points and for d@erent white points with are at their maximum values. The other requirement is the constantphosphor sets. Test results demonstrated that CIE- tristimulus values of the primaries; the red, green, and blue LAB color differences were larger when the phosphor sets phosphors. When the above quantities are known, the CIE were different. Smaller color dt#erences resulted from dtf- tristimulus values X, Y, Z can readily be determined from ferences in white point, assuming a constant phosphor set. -
Color Appearance Models Today's Topic
Color Appearance Models Arjun Satish Mitsunobu Sugimoto 1 Today's topic Color Appearance Models CIELAB The Nayatani et al. Model The Hunt Model The RLAB Model 2 1 Terminology recap Color Hue Brightness/Lightness Colorfulness/Chroma Saturation 3 Color Attribute of visual perception consisting of any combination of chromatic and achromatic content. Chromatic name Achromatic name others 4 2 Hue Attribute of a visual sensation according to which an area appears to be similar to one of the perceived colors Often refers red, green, blue, and yellow 5 Brightness Attribute of a visual sensation according to which an area appears to emit more or less light. Absolute level of the perception 6 3 Lightness The brightness of an area judged as a ratio to the brightness of a similarly illuminated area that appears to be white Relative amount of light reflected, or relative brightness normalized for changes in the illumination and view conditions 7 Colorfulness Attribute of a visual sensation according to which the perceived color of an area appears to be more or less chromatic 8 4 Chroma Colorfulness of an area judged as a ratio of the brightness of a similarly illuminated area that appears white Relationship between colorfulness and chroma is similar to relationship between brightness and lightness 9 Saturation Colorfulness of an area judged as a ratio to its brightness Chroma – ratio to white Saturation – ratio to its brightness 10 5 Definition of Color Appearance Model so much description of color such as: wavelength, cone response, tristimulus values, chromaticity coordinates, color spaces, … it is difficult to distinguish them correctly We need a model which makes them straightforward 11 Definition of Color Appearance Model CIE Technical Committee 1-34 (TC1-34) (Comission Internationale de l'Eclairage) They agreed on the following definition: A color appearance model is any model that includes predictors of at least the relative color-appearance attributes of lightness, chroma, and hue. -
Chromatic Adaptation Transform by Spectral Reconstruction Scott A
Chromatic Adaptation Transform by Spectral Reconstruction Scott A. Burns, University of Illinois at Urbana-Champaign, [email protected] February 28, 2019 Note to readers: This version of the paper is a preprint of a paper to appear in Color Research and Application in October 2019 (Citation: Burns SA. Chromatic adaptation transform by spectral reconstruction. Color Res Appl. 2019;44(5):682-693). The full text of the final version is available courtesy of Wiley Content Sharing initiative at: https://rdcu.be/bEZbD. The final published version differs substantially from the preprint shown here, as follows. The claims of negative tristimulus values being “failures” of a CAT are removed, since in some circumstances such as with “supersaturated” colors, it may be reasonable for a CAT to produce such results. The revised version simply states that in certain applications, tristimulus values outside the spectral locus or having negative values are undesirable. In these cases, the proposed method will guarantee that the destination colors will always be within the spectral locus. Abstract: A color appearance model (CAM) is an advanced colorimetric tool used to predict color appearance under a wide variety of viewing conditions. A chromatic adaptation transform (CAT) is an integral part of a CAM. Its role is to predict “corresponding colors,” that is, a pair of colors that have the same color appearance when viewed under different illuminants, after partial or full adaptation to each illuminant. Modern CATs perform well when applied to a limited range of illuminant pairs and a limited range of source (test) colors. However, they can fail if operated outside these ranges. -
Color Temperature and at 5,600 Degrees Kelvin It Will Begin to Appear Blue
4,800 degrees it will glow a greenish color Color Temperature and at 5,600 degrees Kelvin it will begin to appear blue. But light itself has no heat; Color temperature is usually used so for photography it is just a measure- to mean white balance, white point or a ment of the hue of a specific type of light means of describing the color of white source. light. This is a very difficult concept to ex- plain, because–”Isn’t white always white?” The human brain is incred- ibly adept at quickly correcting for changes in the color temperature of light; many different kinds of light all seem “white” to us. When moving from a bright daylight environment to a room lit by a candle all that will appear to change, to the naked eye, is the light level. Yet record these two situations shooting color film, digital photographs or with tape in an unbalanced camcorder and the outside images will have a blueish hue and the inside images will have a heavy orange cast. The brain quickly adjust to the changes, mak- ing what is perceived as white ap- pear white, whereas film, digital im- ages and camcorders are balanced for one particular color and anything that deviates from this will produce a color cast. A GUIDE TO COLOR TEMPERATURE The color of light is measured by the Kelvin scale . This is a sci- entific temperature scale used to measure the exact temperature of objects. If you heat a carbon rod to 3,200 degrees, it glows orange. -
Soft Proofing & Monitor Calibration
Digital Technology Group, Inc. DTG Digital Color Learning Guide www.DTGweb.com 800.681.0024 Soft Proofing Tampa, FL Soft Proofing Page: 1 The following instructions will help you understand the concept and practice of soft proofing as well as step you through how to soft proof through different applications. General Philosophy & Overview The most frequent tech support phone call we take here at DTG begins with the words...”my print doesn’t match my monitor”. While getting prints to exactly MATCH a monitor is impossible, there’s no reason that we can’t achieve a very close perceptual match. When viewing an image on a monitor you are looking at that image displayed through transmissive light. When viewing a printed image you are viewing it with reflected light.These yield two very different perceptions to our eyes and brains. That’s why “matching” a print to a monitor can be challenging. The solution is a pro- cess called soft proofing. Soft proofing is the process of using your calibrated and profiled monitor, combined with printer/media ICC profiles, to preview how an image (or document) is going to look on printed output. What is needed? A few things are needed for soft proofing besides your computer’s monitor or display... 1) A monitor calibrator. This is a piece of hardware, combined with software, that calibrates your monitor to a known standard. It also produces an ICC profile for your monitor which describes to applications (like Photoshop) how your monitor displays color. 2) ICC Profiles for your printer and media (paper, canvas, etc.) combinations. -
Exploiting Colorimetry for Fidelity in Data Visualization Arxiv
Exploiting Colorimetry for Fidelity in Data Visualization Michael J. Waters,y Jessica M. Walker,y Christopher T. Nelson,z Derk Joester,y and James M. Rondinelli∗,y yDepartment of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA zOak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA E-mail: [email protected] Abstract Advances in multimodal characterization methods fuel a generation of increasing immense hyper-dimensional datasets. Color mapping is employed for conveying higher dimensional data in two-dimensional (2D) representations for human consumption without relying on multiple projections. How one constructs these color maps, however, critically affects how accurately one perceives data. For simple scalar fields, perceptually uniform color maps and color selection have been shown to improve data readability arXiv:2002.12228v1 [cs.HC] 27 Feb 2020 and interpretation across research fields. Here we review core concepts underlying the design of perceptually uniform color map and extend the concepts from scalar fields to two-dimensional vector fields and three-component composition fields frequently found in materials-chemistry research to enable high-fidelity visualization. We develop the software tools PAPUC and CMPUC to enable researchers to utilize these colorimetry principles and employ perceptually uniform color spaces for rigorously meaningful color mapping of higher dimensional data representations. Last, we demonstrate how these 1 approaches deliver immediate improvements in -
Appendix G: the Pantone “Our Color Wheel” Compared to the Chromaticity Diagram (2016) 1
Appendix G - 1 Appendix G: The Pantone “Our color Wheel” compared to the Chromaticity Diagram (2016) 1 There is considerable interest in the conversion of Pantone identified color numbers to other numbers within the CIE and ISO Standards. Unfortunately, most of these Standards are not based on any theoretical foundation and have evolved since the late 1920's based on empirical relationships agreed to by committees. As a general rule, these Standards have all assumed that Grassman’s Law of linearity in the visual realm. Unfortunately, this fundamental assumption is not appropriate and has never been confirmed. The visual system of all biological neural systems rely upon logarithmic summing and differencing. A particular goal has been to define precisely the border between colors occurring in the local language and vernacular. An example is the border between yellow and orange. Because of the logarithmic summations used in the neural circuits of the eye and the positions of perceived yellow and orange relative to the photoreceptors of the eye, defining the transition wavelength between these two colors is particularly acute.The perceived response is particularly sensitive to stimulus intensity in the spectral region from 560 to about 580 nanometers. This Appendix relies upon the Chromaticity Diagram (2016) developed within this work. It has previously been described as The New Chromaticity Diagram, or the New Chromaticity Diagram of Research. It is in fact a foundation document that is theoretically supportable and in turn supports a wide variety of less well founded Hering, Munsell, and various RGB and CMYK representations of the human visual spectrum.