Age effects on colour emotion,preference, and harmony

Two psychophysical experiments were carried out to investigate whether or not colour emotion responses would change with the advance of the viewer's age. Two forms of stimuli were used: 30 single colours (for Experiment 1) and 190 colour pairs (for Experiment 2). Four word pairs, warm/cool, heavy/light, active/passive, and like/dislike, were used to assess colour emotion and preference in Experiment 1. In Experiment 2, harmonious/disharmonious was also used in addition to the four scales for Experiment 1. A total of 72 Taiwanese observers participated, including 40 (20 young and 20 older) for Experiment 1 and 32 (16 young and 16 older) for Experiment 2. The experimental results show that for single colours, all colour samples were rated as less active, less liked, and cooler for older observers than for young observers. For colour combinations, light colour pairs were rated as less active and cooler for older observers than for young observers; achromatic colour pairs and those consisting of colours in similar chroma were rated as cooler, less liked and less harmonious for older observers than for young observers. The findings may challenge a number of existing theories, including the adaptation mechanism for retaining consistent perception of colour appearance across the lifespan, the modeling of colour emotion based on relative colour appearance values, and the additive approach to prediction of colour‐combination emotion. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2011     

An aesthetic measurement method for matching colours in product design

Since it is important to know how to evaluate human emotions reflected in the image of a product during the process of product design precisely, a means of evaluating the aesthetic measurement of the image of a product with colour matching is proposed in this article. This method entails a solid visual angle of the subject, the distribution of colour‐area ratios, and colour images as experimental samples for colour matching. The evaluation was conducted based on a formula of the aesthetic measurement of the coloured area. To ensure that the entire practical colour co‐ordinate system was covered, 111 coloured chips were distributed throughout the implementation procedure. The aesthetic measure of colour harmony in this study was calculated based on aesthetic measure theory; moreover, each of the three given images received three symbolic colour combinations before using the fuzzy theory to determine the relationship between the image and the colour combinations of the products. Observers' evaluations of the fuzzy theory and the aesthetic measurement model were then compared, and the results showed that the proposed method succeeded in obtaining a high degree of satisfaction for the top 2 ranked samples in the aesthetic measurement model evaluation and human evaluation. Although only 2 product designs were used as examples for performing the evaluation procedure, the procedure can also be applied to other products.     

A colour harmony model for two‐colour combinations

This study investigates harmony in two‐colour combinations in order to develop a quantitative model. A total of 1431 colour pairs were used as stimuli in a psychophysical experiment for the visual assessment of harmony. These colour pairs were generated using 54 colours selected systematically from CIELAB colour space. During the experiment, observers were presented with colour pairs displayed individually against a medium gray background on a cathode ray tube monitor in a darkened room. Colour harmony was assessed for each colour pair using a 10‐category scale ranging from “extremely harmonious” to “extremely disharmonious.” The experimental results showed a general pattern of two‐colour harmony, from which a quantitative model was developed and principles for creating harmony were derived. This model was tested using an independent psychophysical data set and the results showed satisfactory performance for model prediction. The study also discusses critical issues including the definition of colour harmony, the relationship between harmony and pleasantness, and the relationship between harmony and order in colour. © 2006 Wiley Periodicals, Inc. Col Res Appl, 31, 191–204, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20208     

Experimental modeling of colour harmony

This study investigates colour harmony in visual experiments in order to develop a new quantitative colour harmony model. On the basis of new experimental results, colour harmony formulae were developed to predict colour harmony from the CIECAM02 hue, chroma, and lightness correlates of the members of two‐ or three‐colour combinations. In the experiments, observers were presented two‐ and three‐colour combinations displayed on a well‐characterized CRT monitor in a dark room. Colour harmony was estimated visually on an 11 category scale from ?5 (meaning completely disharmonious) to +5 (meaning completely harmonious), including 0 as the neutral colour harmony impression. From these results, mathematical models of colour harmony were developed. The visual results were also compared with classical colour harmony theories. Two supplementary experiments were also carried out: one of them tested the main principles of colour harmony with real Munsell colour chips, and another one compared the visual rating of the new models with existing colour harmony theories. © 2009 Wiley Periodicals, Inc. Col Res Appl, 2010.     

Colour preference for Taiwanese floral pattern fabrics

A psychophysical experiment was carried out to investigate factors affecting colour preference for Taiwanese floral pattern fabrics, as a case study of object colour preference. A total of 175 test images of Taiwanese fabrics were used as the stimuli presented on a calibrated computer display. The images were generated on the basis of 5 existing Taiwanese fabrics, each manipulated into 35 images by changing the fabric colour. The 35 colours were selected to cover the most frequently used colours for existing Taiwanese fabrics. The 175 test images were assessed by 76 Taiwanese observers in terms of 9 semantic scales, including Taiwanese style/non‐Taiwanese style, Japanese style/non‐Japanese style, splendid/plain, traditional/modern, active/passive, warm/cool, heavy/light, like/dislike and harmonious/disharmonious. The experimental results reveal two underlying factors: “Splendidness” and “Harmony.” The like/dislike response was found to highly correlate with harmonious/disharmonious, but have poor correlation with Taiwanese style/non‐Taiwanese style. The study also reveals several factors affecting colour preference for Taiwanese fabrics, including the interaction effect of colour and pattern, observer's general liking for the object, and the effect of user experience. These findings can help develop a more robust, comprehensive theory of object colour preference. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 43–55, 2016     

Effect of area on color harmony in simulated interiors

The main aim of this study is to examine the effect of area on color harmony in simulated interior spaces. The secondary aim of the study is to investigate how the term color harmony is defined and the link between color harmony and related terms used to define it. These terms can explain why a color scheme is evaluated as harmonious. Four sets of three-color combinations created by using the hues red, blue, yellow, green, purple, and orange were studied in a simulated office interior emphasizing different proportional use of each color. Firstly, participants evaluated harmony content of the images. Secondly, they evaluated each image regarding the terms related to color harmony. Findings indicated that area had an effect on color harmony for two of the color combinations (warm & cool). However, there were no strong but rather moderate and weak correlations between color harmony and the terms.     

Color harmony in two‐piece garments

Using a categorical scale of 10 U, we have assessed color harmony in two‐piece garments (jackets‐trousers) considering a vicenarian and a quinquagenarian style. The experiment was performed by a panel of 59 Chinese observers (26 males and 33 females) with normal color vision and ages ranging 20–78 years, considering 300 color combinations for each of the two styles. For a given color combination, comparing results in the vicenarian/quinquagenarian styles for female/male observers, and observers below/above 45 years old, we found generally higher harmony scores for the vicenarian style, male observers, and observers older than 45 years. We found statistically significant differences (Welch two‐sample t test, P < 0.001) between color‐harmony results for the vicenarian and quinquagenarian styles, as well as considering the scores reported both by male/female observers and by observers below/above 45 years old. We propose a very simple lineal model fitting our current results with an average root mean square error (RMSE) of 0.70 U in our 10‐unit scale, which is below the one achieved by other complex models previously proposed, and also below the inter‐ and intra‐observer variability in our experiment. From our total experimental results, each of the five traditional color‐harmony principles (complementary hues and equal lightness, chroma, tone, and hue) was found to be valid at a low percentage (53–58% of the cases). © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 498–511, 2017     

Investigation of colour appearance models for illumination changes across media

The key to achieving successful cross‐media colour reproduction is a reliable colour appearance model, which is capable of predicting the colour appearance across a variety of imaging devices under different viewing conditions. The two most commonly used media, CRT displays (soft copy) and printed images (hard copy), were included in this study using four complex images. The original printed images were captured using a digital camera and processed using eight colour appearance models (CIELAB, RLAB, LLAB, ATD, Hunt96, Nayatani97, CIECAM97s, and CAM97s2) and two chromatic adaptation transforms (von Kries and CMCCAT97). Psychophysical experiments were carried out to assess colour model performance in terms of colour fidelity by comparing soft‐copy and hard‐copy images. By employing the memory‐matching method, observers categorized the reproductions displayed on a CRT and compared them to the original printed images viewed in a viewing cabinet. The experiment was divided into three phases according to the different colour temperatures between the CRT and light source, i.e., print (D50, A, and A) and CRT (D93, D93, and D50), respectively). It was found that the CIECAM97s‐type models performed better than the other models. In addition, input parameters for each model had a distinct impact on model performance. © 2001 John Wiley & Sons, Inc. Col Res Appl, 26, 428–435, 2001     

A methodology for predicting the color trend to get a three‐colored combination

A color design/selection system for predicting the color trend based on aesthetic measures is proposed in this article. In this method, the analytic hierarchy process theory was used to evaluate the weights for four major consumption style factors in human environment, including Economy, Education, Culture, and Technology. Then 10 product imageries were selected by using the questionnaire, and mapped the images and the factors with the weighted results and clustered both variables with the corresponding ranks. During the implementation procedure, 111 colors samples covering the entire domain of the PCCS (Practical Color Co‐ordinate System) color system were taken, and the aesthetic measure for three‐colored harmony based on aesthetic measure theory was calculated. Then 200 tri‐colored combinations were divided into 10 clusters by using fuzzy clustering. The three‐colored products were then mapped into each cluster with the calculated grand average and Standard Deviation of the imagery values obtained for the three‐colored products. According to the above implementation logic, the relationship among the consumption style factors, the images, as well as the tri‐colored cars can be obtained, and then used to construct a color trend based on market requirement. With the aid of this system, one can get a three‐colored car to match his/her requirement. Although the selection of three‐colored car is taken as an example to specify the methodology, it can also be used to develop a system for other products. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 102–114, 2017     

Colour harmony of two‐colour combinations using a 3D colour configuration

Over the past few years, although many studies have investigated colour harmony, most of those used the planar colour configuration, which is not in line with the design requirements of real‐life products. Therefore, this study used 11 basic colours and five types of colour scheme techniques to derive 141 colour combinations applied upon a physical 3D colour configuration to observe the phenomena of colour harmony. The results show that colour harmony on a 3D colour configuration is different from that on a planar colour configuration, and can be divided into four phenomena: (i) lightness difference was found to determine the colour harmony while achromatic colour was configured with achromatic colour; (ii) lightness sum prompted colour harmony while chromatic colour was configured with achromatic colour; (iii) lightness sum and chroma sum were found to determine colour harmony while chromatic colour was configured with chromatic colour with a two‐colour hue angle difference >90°; and (iv) lightness sum and hue difference were a determination of colour harmony while chromatic colour was configured with chromatic colour with a two‐colour hue angle difference of ≤90°. On the basis of these phenomena, this study develops a colour harmony model based on the colour parameters, most of which are derived from the addition of the colour attributes of two colours.     

Preference for accent and background colors in interior architecture in terms of similarity/contrast of natural color system attributes

Color combination criteria are said to entail an affective response in interior design. We investigated the color combination criteria that orient the preference of current observers, after Le Corbusier's 1931 Salubra keyboards. We explored the similarity/contrast in Natural Color System (NCS) hue, blackness, and chromaticness in 312 combinations with four colors, two backgrounds and two accent colors, coming from 43 individual colors, on the walls of a simulated interior of a bedroom from the Swiss Pavilion (Le Corbusier, 1930-1931). Participants were 644 students of architecture and interior design in Western Europe and Near East, who evaluated with a Likert scale their preference for virtual images via an online survey. Results indicate that the most preferred color combinations are those with hues closer in the color wheel, being the similarity between hues in the backgrounds more important than in the accent colors, and with NCS B30G to G as the most preferred hues. Observers preferred color compositions with blackness under 10% and similar blackness between the two background colors, together with a certain blackness contrast between these background colors and the two color accents. Similarly, observers liked color compositions with low chromaticness and low chromaticness difference among the four colors of the composition.     

A cross‐cultural comparison of colour emotion for two‐colour combinations

Psychophysical experiments were conducted in the UK, Taiwan, France, Germany, Spain, Sweden, Argentina, and Iran to assess colour emotion for two‐colour combinations using semantic scales warm/cool, heavy/light, active/passive, and like/dislike. A total of 223 observers participated, each presented with 190 colour pairs as the stimuli, shown individually on a cathode ray tube display. The results show consistent responses across cultures only for warm/cool, heavy/light, and active/passive. The like/dislike scale, however, showed some differences between the observer groups, in particular between the Argentinian responses and those obtained from the other observers. Factor analysis reveals that the Argentinian observers preferred passive colour pairs to active ones more than the other observers. In addition to the cultural difference in like/dislike, the experimental results show some effects of gender, professional background (design vs. nondesign), and age. Female observers were found to prefer colour pairs with high‐lightness or low‐chroma values more than their male counterparts. Observers with a design background liked low‐chroma colour pairs or those containing colours of similar hue more than nondesign observers. Older observers liked colour pairs with high‐lightness or high‐chroma values more than young observers did. Based on the findings, a two‐level theory of colour emotion is proposed, in which warm/cool, heavy/light, and active/passive are identified as the reactive‐level responses and like/dislike the reflective‐level response. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2012     

A study of colour emotion and colour preference. Part III: Colour preference modeling

In this study three colour preference models for single colours were developed. The first model was developed on the basis of the colour emotions, clean–dirty, tense–relaxed, and heavy–light. In this model colour preference was found affected most by the emotional feeling “clean.” The second model was developed on the basis of the three colour‐emotion factors identified in Part I, colour activity, colour weight, and colour heat. By combining this model with the colour‐science‐based formulae of these three factors, which have been developed in Part I, one can predict colour preference of a test colour from its colour‐appearance attributes. The third colour preference model was directly developed from colour‐appearance attributes. In this model colour preference is determined by the colour difference between a test colour and the reference colour (L*, a*, b*) = (50, ?8, 30). The above approaches to modeling single‐colour preference were also adopted in modeling colour preference for colour combinations. The results show that it was difficult to predict colour‐combination preference by colour emotions only. This study also clarifies the relationship between colour preference and colour harmony. The results show that although colour preference is strongly correlated with colour harmony, there are still colours of which the two scales disagree with each other. © 2004 Wiley Periodicals, Inc. Col Res Appl, 29, 381–389, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20047     

Lightness dependencies and the effect of texture on suprathreshold lightness tolerances

A psychophysical experiment was performed to determine the effects of lightness dependency on suprathreshold lightness tolerances. Using a pass/fail method of constant stimuli, lightness tolerance thresholds were measured using achromatic stimuli centered at CIELAB L* = 10, 20, 40, 60, 80, and 90 using 44 observers. In addition to measuring tolerance thresholds for uniform samples, lightness tolerances were measured using stimuli with a simulated texture of thread wound on a card. A texture intermediate between the wound thread and the uniform stimuli was also used. A computer‐controlled CRT was used to perform the experiments. Lightness tolerances were found to increase with increasing lightness of the test stimuli. For the uniform stimuli this effect was only evident at the higher lightnesses. For the textured stimuli, this trend was more evident throughout the whole lightness range. Texture had an effect of increasing the tolerance thresholds by a factor of almost 2 as compared to the uniform stimuli. The intermediate texture had tolerance thresholds that were between those of the uniform and full‐textured stimuli. Transforming the results into a plot of threshold vs. intensity produced results that were more uniform across the three conditions. This may indicate that CIELAB is not the best space in which to model these effects. © 2000 John Wiley & Sons, Inc. Col Res Appl, 25, 241–249, 2000     

A study of colour emotion and colour preference. Part II: Colour emotions for two‐colour combinations

Eleven colour‐emotion scales, warm–cool, heavy–light, modern–classical, clean–dirty, active–passive, hard–soft, harmonious–disharmonious, tense–relaxed, fresh–stale, masculine–feminine, and like–dislike, were investigated on 190 colour pairs with British and Chinese observers. Experimental results show that gender difference existed in masculine–feminine, whereas no significant cultural difference was found between British and Chinese observers. Three colour‐emotion factors were identified by the method of factor analysis and were labeled “colour activity,” “colour weight,” and “colour heat.” These factors were found similar to those extracted from the single colour emotions developed in Part I. This indicates a coherent framework of colour emotion factors for single colours and two‐colour combinations. An additivity relationship was found between single‐colour and colour‐combination emotions. This relationship predicts colour emotions for a colour pair by averaging the colour emotions of individual colours that generate the pair. However, it cannot be applied to colour preference prediction. By combining the additivity relationship with a single‐colour emotion model, such as those developed in Part I, a colour‐appearance‐based model was established for colour‐combination emotions. With this model one can predict colour emotions for a colour pair if colour‐appearance attributes of the component colours in that pair are known. © 2004 Wiley Periodicals, Inc. Col Res Appl, 29, 292–298, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20024     

Preference for color‐enhanced images assessed by color deficiencies

In this study, we propose color images with color enhancement for congenital red–green color deficiency on the basis of the model proposed by Mochizuki et al. [In Terrassa, Spain: Proceedings for CGIV, Springfield VA: IS&T 2008;208–213] with the aim of facilitating color customization in displays used by color‐deficient observers. Three types of color enhancements for deficiency were addressed in this study: colors were enhanced along the protan confusion line (i.e., P‐enhancement), deutan confusion line (i.e., D‐enhancement), and a line between the protan and deutan confusion lines (i.e., mix‐enhancement). We investigated the color‐enhanced image that is most preferred by each group of protan, deutan, and normal observers. Protan and deutan in this study indicate observers that are both dichromats and anomalous trichromats. Nine protan, nine deutan, and six normal observers participated in the experiment. The results showed that among the three types of color enhancements, the D‐enhancement provided the best performance for protan observers. For deutan observers, all three types provided effective enhancement, although the P‐ and mix‐enhancements were slightly better than the D‐enhancement. Our results indicated that color enhancement increases the preference evaluations of protan and deutan observers. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 234–251, 2014; Published Online 20 February 2013 in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/col.21795     

Detection and modification of confusing color combinations for red‐green dichromats to achieve a color universal design

Color‐vision deficiency is a relatively common genetic condition, which often leads to the obstruction of necessary information in colored images. It is important to minimize such inconvenient effects in communication using colored images from a universal design perspective. The universal design principle stipulates that all environments and products should be usable by all people, regardless of age, physical attributes, and ability. This article proposes a method to detect color combinations in a given image that would confuse color dichromats, and suggests a way in which to modify them to make the image easily distinguishable for both normal and dichromatic observers. Confusing color combinations were detected based on a color‐difference calculation using simulations of how the color would appear to dichromats. The confusing colors were then modified based on the minimization of an evaluation function, which was defined as the sum of the degree of confusion and the degree of color change from the original image. Several colored images obtained by the proposed method were compared with the originals by red–green dichromatic observers who judged them to be clearer, thereby confirming that the proposed method was effective for color rendering for universal design. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 203–211, 2008     

Colour matching using LEDs as primaries

In our metameric experiment, the colour of a filtered incandescent lamp was matched with the additive mixture of three LEDs in a Lummer–Brodhun‐type visual photometer. Two sets of primaries were used, one had their dominant wavelengths at 467, 533, and 600 nm; the other set had dominant wavelengths at 478, 552, and 635 nm. These values correspond approximately to the characteristic wavelengths of the Prime and Non‐Prime Colour spectral regions defined by W. A. Thornton. 1 Both the light of the incandescent lamp and that of the LED clusters were seen monocularly in a centrally divided bipartite field at a visual angle of 2°. The luminance of the matching fields was in the order of 20 cd/m² to provide sufficient gamut for the LED mixture. Ten young observers with normal colour vision participated in the experiment. The emission spectra of the viewing fields were measured with an array‐type spectroradiometer, and two sets of colour‐matching functions were used to calculate the chromaticity of the matching stimuli: the CIE 1931 standard colorimetric observer and the Judd–Vos modification of the colour‐matching functions. We found that the Judd–Vos modification of the CIE 1931 standard observer represents more accurately the real observers in the evaluation of our results. No systematic differences between the use of the two sets of LEDs were detected in contradiction to Thornton's findings. © 2004 Wiley Periodicals, Inc. Col Res Appl, 29, 360–364, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20044     

Universal models of colour emotion and colour harmony

A new set of quantitative models of colour emotion and colour harmony were developed in this study using psychophysical data collected from 12 regions in the world, including Argentina, China, France, Germany, Hungary, Iran, Japan, Spain, Sweden, Taiwan, Thailand, and the UK. These data have previously been published in journals or conferences (for details see Tables 1 and 2 ). For colour emotion, three new models were derived, showing satisfactory predictive performance in terms of an average correlation coefficient of 0.78 for “warm/cool”, 0.80 for “heavy/light” and 0.81 for “active/passive”. The new colour harmony model also had satisfactory predictive performance, with an average correlation coefficient of 0.72. Principal component analysis shows that the common colour harmony principles, including hue similarity, chroma similarity, lightness difference and high lightness principles, were partly agreed by observers of the same region. The findings suggest that it is feasible to develop universal models of colour emotion and colour harmony, and that the former was found to be relatively more culture‐independent than the latter.     

The impact of signboard-building color combinations on color harmony and legibility

The aim of this study was to investigate the impact of signboard-building color combinations on color harmony and legibility. Two hundred and three participants rated 54 signboard-building color combinations against two scales of color harmony and legibility. In this article, the terms “brick,” “stone,” and “glass” refer to three types of building exteriors used in the experiment (ie, brick masonry, greystone, and curtain walls, respectively). Major findings are as follows: (a) there was a positive linear correlation between color harmony and legibility in all three types of building exteriors, (b) the type of building exterior affected the color harmony and legibility of signboard colors, (c) no hue-related patterns were observed, (d) the effects of chroma differences on color harmony were weak and the effects of chroma differences on legibility were moderate, (e) the effects of lightness differences on color harmony and legibility were strong in brick, but the effects of lightness differences were weak in stone and glass, (f) white color combinations (ie, color pairs including white signboards) turned out to be the most harmonious and legible, and (g) color combinations of light signboards and dark buildings (negative polarity) were rated most harmonious and legible, with the exception of vivid red (positive polarity). The findings of this study provide insight into the characteristics of harmonious and legible colors in the context of signboard design.