bluuebunny/crossref_metadata_2025_split huggingface dataset:
Color harmony: New applications of existing concepts
Authors: Heddell Patricia 
Published: June 2007

AbstractThere is a continuing need in the arts for practical applications of color theories. Many existing color‐harmony theories can be grouped into two categories: those based on complementary color relationships and those based on a common color denominator. Publication of Ellen Marx's book, Optical Color and Simultaneity, makes new applications of complementary harmony possible, while the existence of the OSA Uniform Color Scales samples makes possible new applications of common denominator as well as complementary color theories.
Multidimensional scaling of selected samples from the optical society of America uniform color scales
Authors: Taylor Joann M. , Billmeyer Fred W. 
Published: June 2007

AbstractThe Optical Society of America Uniform Color Scales was produced as an attempt to create a color order system in which equal geometric distances correspond to equally perceived color differences. A psychophysical experiment was designed to determine the perceived visual uniformity within two oblique planar subsets of the Uniform Color Scales. A modified interval‐scaling procedure using perceived value differences within a portion of the Munsell Value scale was used to assess the perceived magnitudes of dissimilarities between sample pairs of the Uniform Color Scales. Multidimensional‐scaling methods were used to analyze the dissimilarity data for the two planar subsets, each of which was judged by five observers. Despite some limited subadditivity for which a number of plausible explanations were provided, each oblique planar subset was shown to demonstrate satisfactory visual uniformity on the basis of the average judgement obtained for five observers. These results also demonstrate that it is possible for human observers to judge dissimilarities within a planar array varying in three attributes of color and to resolve those differences into a true two‐dimensional representation.
The effect of measuring geometry on computer color matching
Authors: Rich Danny C. 
Published: June 2007

AbstractThe debate over the best optical geometry for color measurement dates back to the development of the first recording reflectance spectrophotometer. It is hypothesized that a bidirectional geometry conforms best to the procedure used to inspect colored surface samples visually. This hypothesis was tested using two spectrophotometers of nearly identical design, one utilizing d/8 geometry and the other utilizing 0/45 geometry. The results indicate that bidirectional geometry may be superior to integrating‐sphere geometry when matching standards with varying gloss. The bidirectional measurements are quite sensitive to the size of the source and the detector‐aperture half angle.
The effect of spatial and chromatic parameters on chromatic induction
Authors: Blackwell K. Tiplitz , Buchsbaum G. 
Published: June 2007

AbstractChromatic induction is the change in the perceived color of a visual stimulus caused by surrounding stimuli in the field of view. Most reports of chromatic induction present results for a limited range of center and surround colors. We performed a series of forced response color matching trials in which size, location and color of surrounding visual fields were varied. Results are reported which illustrate that the effect of the surround on the center decreases exponentially as a function of separation between center and surround and that the effect of the surround on the center increases exponentially as a function of surround size. We also show that there is an optimal center‐surround color difference for which chromatic induction is greatest.
Colorimetric calibration of a video digitizing system: Algorithm and applications
Authors: Lee Raymond L. 
Published: June 2007

AbstractIn principle, digitized color video images should be rich and convenient sources of colorimetric information. In practice, these advantages are offset by the difficulty of reliably translating the video camera's output into colorimetric variables. A solution to this problem is outlined here, one which exploits the fact that spectral reflectances of many natural materials vary slowly in the visible. A characteristic vector analysis of reflectances for a set of such materials leads to an algorithm that gives colorimetrically accurate spectral reflectances from the red‐green‐blue output of a video digitizing system. Prior knowledge about the illumination leads to chromaticity and luminance information, which can be comparable in quality to that obtained from a spectrora‐diometer. Some sample retrievals are shown for the algorithm. Since it is designed to correct color biases that are unknown initially, the algorithm has the advantage that images from many sources can be analyzed.
Accuracy of munsell notations in two Japanese color order systems
Authors: Billmeyer Fred W. , Loppnow Glen R. 
Published: June 2007

AbstractThe color chips in two recent color order systems produced by the Japan Color Research Institute, Chroma Cosmos 5000 and Chromaton 707, are denoted by Munsell notations. However,instrumental and visual examination shows that these notations are inaccurate for a significant fraction of the chips. For 1325 cases in which a Chroma Cosmos 5000 chip could be compared to a chip with the same notation in the current U.S. Munsell Book of Color, the CIE‐LAB color difference between them was greater than 3 units (maximum 9.9) 31% of the time, between 1 and 3 units 62% of the time, and less than 1 unit only 7% of the time. Smaller but still significant differences were found for chips from Chromaton 707.
Universal human visual pigment curves from psychophysical data
Authors: Lipetz Leo E. 
Published: June 2007

AbstractA universal spectral absorption curve for visual pigments was used to estimate, first, the visual pigment spectra corresponding to both the photopic psychophysical data of Smith and Pokorny and the scotopic CIE V'λ, and, second, the maximum effective optical density of the visual pigments in each photoreceptor of the “averaged human observer.” These were used to determine improved corrections for light losses in the eye of that averaged observer. The same revised correction held for both long‐wavelength‐ and middle‐wave‐length‐sensitive cones, a different correction was necessary for short‐wavelength‐sensitive cones. To demonstrate the method, the sensitivity spectrum at the cornea for an assumed anomalous middle‐wavelength‐sensitive cone was calculated from these revisions.
Intercomparison on measurement of (total) spectral radiance factor of luminescent specimens
Authors: Billmeyer Fred W. 
Published: June 2007

AbstractThis article is based on a CIE Technical Report that describes an intercomparison of measurements of the (total) spectral radiance factor (SRF) of luminescent materials. Seven luminescent specimens were provided as painted panels: two were white containing fluorescent whitening agents and five were chromatic [green, yellow, orange (two), and red]. The SRFs were measured with direct specimen illumination by a source simulating CIE D65. The SRFs that would have been obtained under D65 illumination were calculated by a method selected from among those previously studied by the committee. Data sets from four laboratories (one supplying two sets) gave useful results. The mean CIELAB color difference from the mean of the five data sets was 2.6 units averaged over all data sets and specimens, with a range among specimens from 1.9 to 3.4 units and among data sets from 1.5 to 4.2 units. The mean color difference from the results of an arbitrary reference laboratory was 3.6 units averaged over all data sets and specimens, with a range among specimens from 3.0 to 4.2 units and a range among data sets from 2.1 to 5.3 units. Maximum values of the SRFs varied considerably among the data sets, from 11.4% to 33.6% among the samples. It was the CIE Technical Committee's feeling that these results are representative of the present state of the art for this measurement, despite the relatively poor performance seen.
Ergonomically optimal crt colours for nonfixed ambient illumination conditions
Authors: Corte Wilfried De 
Published: June 2007

AbstractBuilding on the algorithmic scheme developed by the author, a new computational method is developed to determine an ergonomically optimal set of CRT colours. A set of colours is considered ergonomically optimal when two conditions are met: (a) the smallest colour difference, CIELUV ΔE, between colours is as large as possible, and (b) the selected colours obey certain luminance and saturation constraints. The proposed method is unique in that the colour set is calculated assuming a nonfixed ambient. Two sample applications illustrate the results of the extended algorithm. These results are of particular relevance for the human factors specialist who has to advise on the type of colours to implement on CRT displays that are intended for use in varying illumination conditions.
Spectrophotometric color matching based on two‐constant kubelka‐munk theory
Authors: Walowit Eric , McCarthy Cornelius J. , Berns Roy S. 
Published: June 2007

AbstractAn algorithm is proposed to minimize the spectral difference between the reflectance of a standard and that of a match formed from a mixture of scattering colorants. This method applies linear least‐squares techniques and Kubelka‐Munk two‐constant theory to the calculation of colorant concentrations required to match the K/S curve of a standard. Several advantages may be gained over traditional tristimulus matching: the spectral reflectance of the standard and predicted formulation exhibit lower spectral difference, the use of spectrally similar colorants is enhanced, and formulations can be determined for standards measured over wavelength regions other than the visible spectrum.
Centroids of color categories compared by two methods
Authors: Boynton Robert M. , Maclaury Robert E. , Uchikawa Keiji 
Published: June 2007

AbstractA procedure is described whereby the subset of Munsell colors of maximum chroma, which has been used by anthropologists to study color naming since Berlin and Kay in 1969, can be specified in the L,j,g coordinate system developed more recently by the Uniform Color Scales Committee of the Optical Society of America. The latter permits a meaningful specification of the centroid location of colors named by each basic term. The procedure is validated by comparing centroids obtained from six subjects who named samples of both the Munsell and OSA sets, and its usefulness is illustrated by comparing data from a four‐year old who named only OSA samples and four‐ and two‐year‐olds who named only Munsell colors.
Multiple metamers: Preserving color matches under diverse illuminants
Authors: Burns Scott A. , Cohen Jozef B. , Kuznetsov Edward N. 
Published: June 2007

AbstractThis article extends matrix‐R operations, developed by Cohen and Kappauf in 1982 and 1985 and by Cohen in 1988, to create generalized metameric object color stimuli, here termed multiple metamers, that remain metameric with respect to several different illuminants. As discussed in prior literature, matrix‐R operations resolve any radiometric function (specifying a color stimulus) into a fundamental color stimulus and a residual or metameric black, as hypothesized by Gunter Wyszecki in 1953. The fundamental is sensed by the visual system while the residual is ignored. Metameric color stimuli comprise the same fundamental but different residuals. Thus, matrix‐R operations easily construct metameric suites under an equal‐energy source or under any other illuminant whose physical specification is incorporated into the radiometric function of the color stimulus entering the visual system. In the present article, matrix‐R operations are extended to create metameric stimuli that theoretically remain metameric with respect to an arbitrary number of sequential illuminants. While the stimuli remain metamers under different illuminants, the color sensation evoked with respect to one illuminant is generally different from the color sensation evoked with respect to another illuminant. Examples demonstrate multiple metamers with respect to CIE standard illuminants A and C and with respect to four artificial illuminants. In principle, extended matrix‐R operations create multiple metamers with respect to different observers, or with respect to any combination of observers and illuminants.
Analyzing the natural color system's color‐order system by using a nonlinear color‐appearance model
Authors: Nayatani Yoshinobu , Umemura Yoshifumi , Hashimoto Kenjiro , Takahama Kotaro , Sobagaki Hiroaki 
Published: June 2007

AbstractThe Natural Color System (NCS) is analyzed by using a nonlinear color‐appearance model. Perceptual uniformity was examined for each of the NCS attributes of blackness (s), chromaticness (Cr), and hue. Some nonuniformities were found in chromaticness and hue spacing, which were probably the result of the assessing and scaling method used in developing the system. In addition, a colorimetric interpretation is given to a principal plane in the NCS consisting of the colors with (s,Cr) = (50,0) and (0,100). The colors with (0,100) have different values of Y for different hues. Based on the analysis, a method is developed to predict the NCS attributes from the values x, y, Y of an object color by using the nonlinear color‐appearance model. The present analysis clarifies the importance of the NCS system in studying the color appearance of object colors.
Architects' colour terminology: Is there order?
Authors: O'Connor M. , Whitfield T. W. A. , Wiltshire T. J. 
Published: June 2007

AbstractIn this article we argue that colour order systems represent the conceptualisations of experts and that little attention has been given to how nonexperts in color theory and terminology conceive of colour. Following previous work with British architects1,2, our attention was directed toward this group as a major example of users of colour who are, from the point of view of theoreticians, nonexperts. Given the difficulties of revealing conceptual structures, architects' natural terminology provided the focus of the study. Two tasks were administered: the first sought to identify the main colour terms architects used, while the second sought to group these terms under meaningful descriptors. The main questions of interest concerned the identity of such descriptors, their conceptual organisation, and the correspondence between architects' descriptors/terms and those used in colour‐order systems.
Influence theory for color constancy models
Authors: Stine Wm. Wren , Sparrow John E. 
Published: June 2007

AbstractThe problem that color constancy models address is one of recovering the reflectances of a surface under different illuminants and spatial configurations. As models of the human visual system, they should recover surface reflectances when the human visual system recovers those reflectances and fail when the human visual system fails to recover those reflectances. Unfortunately, it is difficult to determine just when these models will recover surface reflectances and when they will fail. We introduce a theory of influence that quantifies the degree to which the lightness calculated for a given surface element is influenced by the receptor responses to other elements. Influence theory is shown to be a very useful tool for highlighting testable predictions that can discriminate among color constancy models without having to determine directly when they will recover surface reflectances. This technique for generating empirical predictions is demonstrated by studying the effects of choosing different normalizing functions on an asymptotic retinex algorithm.
Artificial daylight for measurement of optical properties of materials
Authors: Terstiege Heinz 
Published: June 2007

AbstractRadiometric properties of materials for lighting and building have to be known in the UV, visible, and IR regions of the spectrum. Radiometric and photometric properties can be measured with spectrometers independent of the spectral power distribution of the irradiating source used for measurement provided there is sufficient radiant energy available at all measured wavelengths. However, for luminescent materials a precise simulation of the reference illuminant has to be used for measurement, otherwise the measured characteristics are meaningless.
An evaluation of methods for producing desired colors on CRT monitors
Authors: Post David L. , Calhoun Christopher S. 
Published: June 2007

AbstractThree experiments were performed to evaluate methods for generating colors having desired CIE chromaticity coordinates and luminances on CRT monitors. Methods based on piecewise linear interpolation were found to yield better accuracy than others based on linear regression. Comparisons between two monitors revealed no substantial differences in accuracy, but the monitor's state of adjustment was found to have important effects. Evidence was also obtained concerning the number of CRT measurement points needed to obtain maximum accuracy from the interpolation‐based methods. The methods' accuracies are characterized and avenues for improvement are suggested.
A planar‐vector based color space for graphic arts color analysis and reproduction
Authors: Huntsman James R. 
Published: June 2007

AbstractA new color space is developed, based on a model of a trigonally symmetric, planar arrangement of three response vectors, which first separates a visual stimulus via tristimulus values into achromatic and chromatic components and then recombines them. Because three visual response vectors are mutually opposed, the model is called the mutually opposed, trichromatic response (MOTR) model. The MOTR model does not introduce any new visual concepts but rather uses established concepts in an empirically different way. The MOTR model directly represents a color as a combination of two chromatic primaries and one achromatic primary. It is, therefore, particularly useful for halftone color reproduction based on two primary colors plus black, sometimes referred to as 100% GCR (gray component replacement). It is useful also because of its linearity properties between lightness and the chromatic and achromatic contents. The MOTR model's color space is applicable to existing color‐order systems and provides a graphic representation often better than CIELAB and CIELUV do. The MOTR model is also consistent with many known visual characteristics such as unique hues, illuminant adaptation, wavelength discrimination, and defective color vision. The model as described herein is limited to the comparison of related colors under a given photopic luminance.
Unique hue loci and implications
Authors: Ikeda M. , Uehira I. 
Published: June 2007

AbstractUnique hue loci of red, yellow, green, and blue were obtained for lights of 0.5 and 2 cd. m‐2 from five normal color vision subjects. Most loci curved on the chromaticity diagram. This result excludes linear equations of colormatching functions as candidates for spectral sensitivity functions of opponent color systems, (r/g)λ and (y/b)λ. The chromatic valence curves of two opponent color systems obtained by the so‐called cancellation experiment were analyzed in relation to the unique hue loci and it was shown that the appearance of the valence curves can be manipulated at will by choosing the cancellation light at various points on the chromaticity diagram. A similar manipulation was also demonstrated for the additivity property of chromatic valence and it was made clear that no unique solution is obtainable.
R/G and Y/B opponent‐color mechanisms revealed in temporal integration for bichromatically mixed lights
Authors: Kawabata Yasuhiro , Aiba Thomas Satoru 
Published: June 2007

AbstractIn the present study, the critical durations for temporal integration at theshold were obtained for bichromatically mixed (red/green and yellow/blue) test lights presented against darkness and achromatic backgrounds of different intensities. Critical durations crucially depended on the mixing ratio of the red and green components: it was shortest when red and green components were balanced in intensity canceling chromaticness of both components, and longer for red and green monochromatic lights. This trend was pronounced with backgrounds of higher intensities but was not obvious with dim backgrounds. The results of yellow/blue condition showed that critical durations were shorter when yellow component was dominant, as well as when yellow and blue components were balanced in intensity canceling chromaticness of both components, but when blue monochromatic light was dominant, it was longer than in other mixture conditions and changed less with the elevation of the background intensity. The results were interpreted as demonstraing the red/green and yellow/blue opponet‐color mechanism's participation.
Color notation by visual interpolation in colour order systems: How accurate is it?
Authors: Döring Günter 
Published: June 2007

AbstractSystematic collections of colour samples from colour order systems are used in many cases, e.g., in architecture and in design. Usually, the colour that a designer has in mind is not found as a colour sample within the collection at hand, but has to be determined by visual interpolation between the available samples. However, because the colour coordinates of the available samples deviate from those of the aim points, these deviations give rise to uncertainties during visual interpolation.I have investigated the influence of the colorimetric accuracy of the colour samples in the collection used on the precision of colour notation by visual interpolation. This research shows that the accuracy of notation by visual interpolation is not influenced by the colorimetric precision of the colour collection alone, but also by the magnitude of the colour differences between adjacent colour samples in the respective colour collection and by the directions of the colour differences from the aim points.
Coexisting or mingling: The visual aspect of the problem in the urban context
Authors: Tosca Theano Fanny 
Published: June 2007

AbstractThe residents of a working‐class settlement in the north of Greece were the subjects of a three‐stage study to determine the degree of satisfaction these people found in their surroundings. The ultimative objective was to take a highly disparate group of individuals and unify them both as a community and with the surrounding Greek population by designing an environment that blends the individuals' colour tastes. The main aspects of the investigation were (a) the residents' use of public spaces, (b) their evaluation of them from functional, psychological, visual, and aesthetic points of view, and (c) their colour preferences (colour palette and combinatory principle) for building exteriors. The second and third stages of the research focussed on, respectively, semantic differentiation and an analysis of a sample building facade by colour elements. The main difficulties in this research resulted from the very disparateness of the population (refugees of various origin), the indifference of the authorities, and the bissection of the area by a highway. In the coloration proposals resulting from the research, the accomplishment of the main objective on the level of the visual and psychological reaction of the users to an organic coloration of their building facades was attempted. Social, semantic, synthetic, and technical factors were taken into account.