Background and foreground interaction: Influence of complementary colors on the search task

Labels are indispensable visual (communication) elements that completely deliver the geospatial message of maps. The objective of this study is to investigate the impact of complementary colors between the map's background and text on the readability of cartographic texts and thus on the efficiency of the map user's search task. This is compared with the use of the “traditional” black labels on the corresponding colored backgrounds. Furthermore, a number of user characteristics, such as gender and expertise, are taken into account as well. The users' eye movements were registered to study their attentive behavior during the visual search task. In addition to the complement of the color's hue, the analyses were based on the difference in luminance, which could also affect the labels' readability. The difference between the black and colored label design was significantly different versus the eye‐tracking metrics. A correlation was found between the color difference and reaction time measurement and between the luminance difference and fixation duration. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 437–445, 2015     

Visual assessment of light source color quality

The color quality of the lit visual environment can be improved by optimizing light source spectral power distributions. For a comprehensive optimization, it is important to identify the relationship among the perceptual properties of color quality. In this work, a colorful still life or tabletop arrangement was constructed from real artificial objects. Thirty observers with normal color vision scaled nine different properties of color quality under three light sources, incandescent, fluorescent and white LED. Six factors were extracted from the correlations among the obtained visual color quality scales. Factors were assigned the following labels: memory, preference, brightness, fidelity, gamut and difference. Mean factor values were computed for each light source. Significant differences were found in case of preference, brightness and fidelity: for preference, INC was rated better than CFL and LED was rated better than CFL, for brightness, LED was better than INC and LED was better than CFL and for fidelity, INC was better than CFL and INC was better than LED. The brightness factor was consistent among the observers. Three clusters of observers were found for preference and fidelity. The memory, gamut and difference factors showed large interobserver variability. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2013     

Performance testing of color-difference metrics using a color tolerance dataset

A color-difference dataset was developed for testing the performance of color metrics. The dataset comprises 45 color-difference vectors varying in five directions at nine color centers under conditions typical of commercial color decisions. Probit analysis was used to estimate the parameters of the population distribution of tolerances for each vector. In addition to estimating the median tolerance, the anlysis allows one to estimate the uncertainty of a tolerance and to test the adequacy of the underlying model tolerance distribution. The median tolerances were used to specify 45 color-difference pairs with equal visual color-difference magnitudes. The performance of eight color-difference metrics was compared using the normalized standard deviation of the color differences of the visually equal difference pairs as a measure of uniformity. A bootstrap statistical technique was used to quantify the variation in performance with varying samples of color centers and color-difference directions and to determine the significance of observed differences in uniformity performance. Some metrics based on weighted CIELAB dl*, dC*, dH* color-difference components had significantly superior performance compared to the CIE recommended color-difference metrics.     

Latent spaces of color preference with and without a context: Using the shape of an automobile as the context

This article compares color preferences with a context to color preferences without it, using chips of 50 colors and the shape of an automobile as the context. Subjects were asked to make preference judgments of the color chips with the shape and also without it in the experiment. Multi- variate analyses were performed on the two sets of data to deriue latent spaces of color preference with and without the context. Through interpretation and comparison of the derived spaces, it was found that there was a noticeable context effect between the preference judgments.     

Gender difference in color preference across cultures: An archetypal pattern modulated by a female cultural stereotype

A gender difference in color preference among British participants has been repeatedly reported, in which both males and females show a preference for blue‐green colors, while females express an additional preference for pink‐purple colors. To investigate the robustness of gender difference in color preference in a different culture, we tested 81 young adult Indians from a school of design and compared them to 80 young British students in Psychology. The 35‐item International Personality Item Pool (IPIP) and Bem Sex Role Inventory (BSRI) questionnaires were also administered to explore possible links between personality traits, gender schemata, and color preferences. Results confirmed a gender difference in both cultures; participants collectively expressed a preference for cool over warm colors, while in addition females showed a preference for pink colors, with a warm bias for Indian females and a cool bias for British females. While these results extend gender difference to Indian culture and support the universality of an underlying pattern they also reveal a culture‐specific contribution essentially observed in females. In British participants, color preference was correlated exclusively with BSRI scores in females and overwhelmingly with IPIP scores in males; this gender‐specific pattern of correlation was not replicated in the Indian sample. Results point to an archetypal pattern of gender difference in color preference with a remarkable cross‐cultural similarity in men and a subtle but significant cultural difference in women whose origin is yet to be explained.     

Evaluation of methods for verifying the performance of color‐measuring instruments. Part I: Repeatability

A recent ASTM specification (ASTM E2214‐02) was created to standardize the terminology and procedures used to evaluate color measuring instruments. This specification addresses the need for uniformity among the manufacturers of such instruments when quantifying the performance of their products. The scope of E2214 is necessarily large, covering the procedures required to compare instruments for a variety of metrics, all of which are important to their overall performance. In this work, we will focus on one aspect of the instrument evaluation: repeatability performance. We will present repeatability results from a long‐term study of twelve commercial spectrophotometers. Comparisons will be made between traditional color difference metrics and the more complex multidimensional methods specified in E2214. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 166–175, 2007     

Wpt (waypoint) shift manifold difference metrics for evaluation of varying observing-condition (observer + illuminant) metamerism and color inconstancy

Metamerism is a critical color phenomenon which can cause serious problems for products assembled by various parts. Customers generally expect all parts are color-matched under different observing conditions. This article extends the concepts of illuminant and observer metamerism to observing-condition metamerism, that is, objects are color-matched under one observing condition but not under others. The color inconstancy of a single object is also expanded to be evaluated under multiple observing conditions. Moreover, four Waypoint (Wpt) Shift Manifold difference metrics are proposed to evaluate not only observing-condition metamerism of metamers and paramers but also observing-condition color inconstancy of single objects: The Mean Object Inconstancy Index (MOII), The Mean Object Color Difference (MMOCD), Object Metamer Index (OMI), and Object Hue Similarity Index (OHSI). Existing indices of metamerism and color inconstancy employ appearance matching using a Chromatic Adaptation Transform (CAT) and color difference formulas such as CIEDE76 or CIEDE2000. The proposed metrics utilize material matching based upon the Waypoint Material Adjustment Transform (Wpt-MAT) and Euclidian color difference in the perceptually uniform Material Color Equivalency Space WLab. Conceptual comparisons between these approaches are discussed and evaluated. Additionally, computational evaluation results under observing conditions composed by 99 illuminants and 70 observers show that MOII provides a measure of color inconstancy for single objects, MMOCD provides a measure of metamerism between metamers and paramers with a generalized assessment of color difference between two objects, OMI provides a measure of paramers, and OHSI provides a quantitative measure of hue characteristics for different observing conditions.     

Comparative studies on color preference in Japan and other Asian regions,with special emphasis on the preference for white

The results of three surveys are presented. The first survey was carried out in four large cities in Japan, and the findings were analyzed by factor analysis and cluster analysis. The second survey was carried out in Seoul, Korea and Tokyo, Japan to determine color preference in the two countries, focusing on the preference for white. The last survey compared color preference in Taipei and Tokyo, also with emphasis on the preference for white. In these successive studies on color preference in Japan and other Asian cities, the subjects were mainly asked to choose from a color chart the three colors they liked most and the three they liked least, and to state the reasons for their choices. The results of Survey 1 showed that color preference could be influenced by differences in age, sex, and geographical region. Also factor analysis and cluster analysis indicated some relation between color preference and the subjects' life styles. Dual scaling analysis of the results of Surveys 2 and 3 indicated that each Asian area has unique color preference tendencies and that there are statistically significant differences in the frequency of selection of colors of certain hues and tones. However, a high preference for white was common to all areas, along with preferences for some other colors. These results thus demonstrated a common strong preference for white in three neighboring Asian areas. The reasons given for the choices suggested that besides the factors of age and sex, associative images based on environmental and cultural aspects may be an important factor influencing color preference. © 1996 John Wiley & Sons, Inc.     

RIT‐DuPont supra‐threshold color‐tolerance individual color‐difference pair dataset

The RIT‐DuPont dataset has been used extensively for formula development and testing since its inception during the 1980's, for example, in the development of CIE94 and CIEDE2000. The dataset was published as 156 color‐tolerances, T₅₀, along specific vector directions about 19 color centers. Probit analysis was used to transform judgments of 958 color‐difference pairs by 50 observers to these 156 tolerances. For most statistical significance testing, the number of samples determines the confidence limits. Thus, there was an interest in publishing the individual color‐difference pair visual and colorimetric data to improve the precision of significance testing. From these 958 pairs, 828 pairs had determinable visual differences. The others had either excessive visual uncertainty or had unanimous visual judgments such that visual differences were undefined. In addition, a method was devised to assign visual uncertainty to each of these pairs using the principles of maximum likelihood and the T₅₀ values. Comparisons were made between the T₅₀ and individual color‐difference pair data both including and omitting uncertainty weightings. The weighted dataset was found to be equivalent to the T₅₀ tolerances. © 2009 Wiley Periodicals, Inc. Col Res Appl, 2010     

日化香精在染发产品中的应用

根据染发类产品的特性,分析染发类用香精和其它香精的区别,调配适合用于染发类产品的日化香精,研究不同香型香精在染发产品中的应用。     

A systematic approach of predicting color preference on the basis of gray relational grade

During the color design process, it is critical to create diversified color schemes for various consumer groups. It is also important to allow members in a design team to brainstorm for creative ideas. A theory of inspecting natural color elements was proposed in this study based on the CIE 1976 (L*,a*,b*) (CIE 1976) color space and the fuzzy c‐means clustering method. A calculation model was built to determine people's preference for colors based on a serialized system. To determine which factors affect the prediction of consumers' preference for a series of products, a gray relational color preference system was used in combination with gray relational grade so that a designer can obtain reasonable prediction results. The proposed system recommends not only the optimal colors for a product but also the optimal color scheme for a series of products.     

Visual determination of suprathreshold color-difference tolerances using probit analysis

As part of a research program to improve the relationship between visual and numerical color-difference evaluation for industrial colorimetry, a color-difference tolerance data set for fitting and testing of color-difference metrics has been extended to include 156 individual color-tolerance determinations. These tolerances were designed to sample 19 color centers over a surface color gamut with balanced sampling of lightness and chromaticness differences. The tolerance determination procedures emphasized accurate estimation of population visual color-difference response and rigorous estimation of tolerance precision. Tolerance accuracy was confirmed by excellent agreement of these results and the majority of previous experiments on five color centers selected for CIE color-difference evaluations. The average uncertainty of the tolerance determinations was ± 11% of the tolerance value at a 2 ó level (95% confidence interval). The completed data set is suitable for estimating the parameters of color-difference metrics or testing the performance of such metrics. The color tolerances indicated the systematic lack of uniformity of the CIELAB space, in general agreement with previous experiments. A simple modification of the CIELAB color-difference metric was shown to account for much of the systematic lack of uniformity.     

Study on the preference of city color image selection based on the logistic model: A case study of Shanghai

With the continuous progress of urbanization, China's urban color planning has begun to receive attention, but there are still many problems in the quality of color environment. In order to clarify further the urban color positioning of our country, the detailed urban color planning objectives are set up, and the opinions of residents with different attributes are included in the consideration scope of urban color planning objectives, so as to guide the future urban color planning scientifically. From the perspective of urban residents' preference, this article takes Shanghai as an example to analyze the difference of residents' preference for urban color selection with different attributes. In this article, the logistic regression model was used to analyze the results of residents' choice, so as to conclude that the significant factors influencing residents' preference for city color image include age, monthly income, current city of residence, frequency of coming to Shanghai and whether they have been to other countries. Therefore, paying attention to the above significant attributes of residents and carrying out in-depth research can provide reference value for the status of the city's future color image.     

Color preference affected by mode of color appearance

Most color preference research focuses on colors in an object color mode. In our daily life, however, colors are perceived not only as an object color mode but also as other modes, such as unnatural object color and light source color modes. To explore the effect of the color appearance mode on color preference, we examined the relationship between color preference and the mode of color appearance. Thirty‐three color chips were chosen from the Munsell notation varying in hues and chromas. The color chips were presented in different color appearance modes by changing the subject's room illuminance and the color chip room illuminance. The experimental results showed that the brightest and most saturated colors were preferred. It was found that the subject preferred color in a light source color mode and unnatural object color mode to color in an object color mode. Moreover, we found that hue had a small effect on color preference in the light source color mode. We also investigated the relationship between color preference and the perceived color attributes (perceived chromaticness, whiteness, and blackness). In a supplementary experiment, elementary color naming was conducted. The results showed that the perceived chromaticness, perceived whiteness, and perceived blackness play a role for the determination of color preference for different color appearance modes. We, consequently, suggest that color preference is dominated not only by color attributes but also by the mode of color appearance. © 2009 Wiley Periodicals, Inc. Col Res Appl, 2010     

Hydroxyethyl cellulose-based indicator labels to track freshness of anchovy (Engraulis encrasicolus)

In this study, it was aimed to develop a freshness indicator label that changes color with spoilage of fish. Hydroxyethyl cellulose-based indicator labels were prepared using two different mixed indicator (bromothymol blue/phenol red, cresol red/thymol blue) formulations. The functionality of prepared indicator labels was tested on anchovy (Engraulis encrasicolus) stored at 2°C and 10°C. Changes in total mesophilic aerobic bacteria, Pseudomonas spp., total yeast and mold counts, and total volatile basic nitrogen (TVB-N) contents of anchovy during storage were examined. Color changes of prepared indicator films were measured by a colorimeter. Correlation between color changes of indicator labels with microorganism growth and content of TVB-N was investigated. It is concluded that developed indicator labels change color with spoilage of anchovy and can be used as freshness indicator in fish industry.     

Evaluation of the quality of different D65 simulators for visual assessment

In this study psychophysical experiments were conducted to investigate the visual color differences of 77 textile metamers using a gray‐scale rating method under five D65 simulators. The quality of each of the D65 simulators was quantified according to the method provided in CIE Publication No. 51.2 using the visible range metamerism index (MI_vis). The five D65 simulators were categorized from A to D according to their MI_vis values. The color difference of each metameric pair was calculated using the spectral power distribution (SPD) of CIE illuminant D65 and artificial SPDs of D65 simulators. The performance factor (PF/3) was used to indicate the agreement between visual differences under five D65 simulators as well as between instrumental color difference and visual difference. Observer accuracy and observer repeatability were also analyzed by PF/3 measure. The experiment results showed that the visual data obtained from category A and B D65 simulators were in good agreement with the PF/3 measure and had no statistical difference in a pair comparison t test. The results also indicated that better agreement between instrumental and visual color differences was obtained using the artificial SPDs of the D65 simulator than with the SPD of CIE illuminant D65. The general color rendering index, Ra, for each D65 simulator was calculated by the CIE No. 13.3 method. © 2002 Wiley Periodicals, Inc. Col Res Appl, 27, 243–251, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10061     

Image color-appearance specification through extension of CIELAB

An extension of the CIE 1976 (L*, a*, b*) color space, CIELAB is described for applications in color reproduction. This extension incorporates a more accurate model of chromatic adaptation, capability to distinguish between the modes of appearance of reflective and self-luminous stimuli, and adjustments to account for changes in surround. The extension of CIELAB is referred to as the RLAB color space. This color space can be used for calculating metrics of lightness, chroma, hue, and color difference. It can also be used to determine the required colors for reproduction across changes in media and viewing conditions. A pilot experiment testing the RLAB model for cross-media color reproduction is also described.     

Distance metrics for very large color differences

Small, supra-threshold color differences are typically described with Euclidean distance metrics, or dimension-weighted Euclidean metrics, in color appearance spaces such as CIELAB. This research examines the perception and modeling of very large color differences in the order of 10 CIELAB units or larger, with an aim of describing the salience of color differences between distinct objects in real-world scenes and images. A psychophysical experiment was completed to compare directly large color-difference pairs designed to probe various Euclidean and non-Euclidean distance metrics. The results indicate that very large color differences are best described by HyAB, a combination of a Euclidean metric in hue and chroma with a city-block metric to incorporate lightness differences.     

Synthetic Photochromic Sodalite

Synthetic photochromic sodalite was prepared (1) by solid-state reaction, (2) from zeolite X-SO₂ or zeolite X-H₂S, and (3) hydrothermally; the preparations are compared and discussed. X-ray diffraction, ultraviolet and visible light absorption (transmission and reflection), and ESR data served to follow the reactions and characterize the products. The content of sulfur and chlorine and the S: C1 ratio affect the depth of color and the bleaching rate. The partial substitution of other halogens for C1 may speed up or slow down the coloring rate as a function of electronegativity. Fluorine may shift the visible absorption maximum from 5300 to 5100 Å. Stoichiometry and ESR data indicate that the photochromism is effected by the transfer of an electron between sulfur as S₂= and a C1 vacancy between four sodium atoms.     

Experimental determination of the laws of color harmony. Part 4: Color preference and the color harmony content

In 1956, we decided at the Budapest University of Technology and Economics to start a large‐scale experiment on color harmony. The experiments and the processing of the experimental results have been completed in 2006. These experiments, described in this article, form a study of how much are people, participating in the experiment, influenced by their own personal color preference in judging the harmony content of a composition. These experiments have utilized the results of former (1958–1969) color preference experiments and the system of color preference indexes, which were developed by the generalization of those results. Within the framework of these experiments, conducted between 1998 and 2006 there were 24 compositions, shown to the participants, at first one by one, then in pairs and at last in groups of six. They had to assess the harmony content of the compositions and award a score on a scale between 0 and 10. Each composition possessed a specific amount of harmony content according to the rules of color space, based on the Coloroid harmony threshold and verified by former experiments. In these experiments the number of elementary observations were 135 568. The people participating in the experiment were approximately equal number of men and women, from the age group between 10 and 70 years. During processing, by using the color preference numerical indexing system, we compared the results of those experiments with the color preference of a similar age group, by using color compositions, identical to the ones used in the present experiment. We have found that the sensation of the color harmony and its intensity have a strong relation to how the observers relate to colors and also their color preferences. The sensation of color harmony is also influenced by the gender and the age of the observer. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 210–224, 2009