Color Research and Application最新文献

Facial brightness perception is affected by skin color. It was reported that reddish skin was matched with a higher lightness scale stimulus than yellowish skin among Japanese observers. However, this trend is inconsistent among Thai, Korean, Chinese, and European observers, implying the influence factors, such as ethnicity, environment, and judgment criteria. In this study, we investigated the influence of the experimental method on facial brightness perception using test stimulus images with constant lightness and different hue angles. We examined two instructions (“Appearance match” vs. “Brightness match”) and the scale stimulus for matching (a uniform color patch vs. a face image). We further conducted an impression evaluation experiment of the whole face. The matching results from the Japanese showed a similar trend in both instructions and scale stimuli under most conditions, suggesting that matched brightness is not influenced by instruction and the complexity of scale stimuli. The impression evaluation results were similar for Thai, Japanese, and Chinese observers, with reddish faces being evaluated with higher scores in brightness. Our findings suggest the influence of experimental methods on facial brightness judgment. The holistic judgment of facial brightness would be universal among different East Asian groups, at least for the range of variation in skin color we used.

Owing to the need for beauty in modern society, cosmetics are essential to enhance femininity and attractiveness. Lipstick is effective in reinforcing femininity and increasing beauty. This study conducted a psychophysical experiment to investigate the association between lipstick colors and the impressions they create. Thirty-five observers were invited to participate in the experiment. They were asked to assess 20 lipstick colors on 23 impression scales. The results showed that the impressions created by the lipstick colors comprised three factors: charm, cuteness, and contemporary. Charm was correlated with a* and lightness value of lipstick color and the color difference between lipstick-skin colors. Cuteness was negatively correlated with the hue angle of the lipstick colors and lightness differences between lipstick-skin colors. Contemporary was correlated with chroma differences and negatively correlated with b* of lipstick color. These lipstick colors can be classified into three groups based on impression factors. The results showed that a* value of lipstick color and the color difference ($��△�E�$) between lipstick and skin color are identified to determine the grouping of lipstick colors.

In the field of physics education, the identification of students' preconceptions—especially regarding light and color—has been pivotal, as these foundational ideas often persist through higher education. Within teacher education, this is particularly crucial, as these early conceptions can deeply influence how future educators understand and teach these concepts, highlighting the need for an approach that weaves these initial understandings into a coherent scientific framework. Instructing students on color concepts reveals that many grapple with the fundamental optical principles. These initial understandings are integral to designing educational sequences that facilitate conceptual evolution, allowing for a deeper grasp of scientific ideas. This study aimed to examine and interpret the initial conceptions that aspiring primary and secondary educators hold about color and its optical fundamentals, while also developing and applying virtual teaching resources to promote a conceptual change about these foundational concepts. A quasi-experimental approach was employed, comprising control and experimental groups, and utilizing both qualitative and quantitative methods for a comprehensive analysis. Engaging 409 trainee teachers through non-probabilistic sampling, the study stratified participants by degree program. These groupings facilitated a comparative evaluation of the pedagogical efficacy of the educational resources developed. The study utilized an online assessment comprising single-answer multiple-choice questions, grounded in prior research, which was psychometrically validated. Educational tools were then developed and implemented to foster a deeper understanding of color concepts among prospective teachers. Results analysis highlighted the existence of preconceptions about color among participants from diverse educational backgrounds. The interventions employed were effective in catalyzing a shift in conceptual understanding and in elevating the knowledge levels of the trainee teachers.

When participants sort color samples into piles, Boster showed that their color groupings can resemble the “stages” of Kay and McDaniel's model of color term evolution. Boster concluded that both the unfolding of color piles in a sequential color sorting task and the unfolding of color terms according to Kay and McDaniel's model reveal how human beings understand color. If this is correct, then: (1) pile sorts should be reasonably robust across variations in the palette of colors to be sorted, as long as the palette contains good examples of Berlin and Kay's universal color categories, and (2) pile-sorting should be more related to lexical effects and less related to perceptual processes governed by similarity judgments alone. We report three studies on English speakers and Somali speakers (Study 1 only), where participants sorted colors into 2…6 piles. The three studies used varying numbers of palette colors (25, 30, or 145 colors) and varying chromaticity schemes (mainly hue, widely-separated in hue and lightness, or densely distributed at high chroma). We compared human sorting behavior to Kay and McDaniel's model and to the “optimal” patterns of color sorting predicted by Regier's well-formedness statistic, which quantifies the perceived similarity between colors. Neither hypothesis is confirmed by the results of our studies. We propose that color sorts are determined by pragmatic influences based on heuristics that are inspired by the palette of colors that are available and the task that the viewer is asked to perform.

This study aims to empirically test whether identifying as a supporter of either New South Wales (NSW) or Queensland (QLD) rugby league teams influences the extent that their respective team colors blue and maroon are associated with positively and negatively valenced words. We used a valence categorization experiment and affective rating task (valence and preference) to investigate if team affiliation and shared ingroup experience influenced affective associations with team colors. NSW supporters were faster and more accurate when categorizing positive words presented in blue than maroon font and negative words in maroon than blue font. While QLD supporters did not significantly differ when categorizing words in either blue or maroon, they rated blue and maroon equally positively in contrast to the NSW supporters. Results from this study give us greater insights into how color-valence associations can be formed through subcultural ingroup affiliations.

The DIN color system is a visually uniform system adopted as the standard by several countries in central Europe. Currently, the conversion method from CIE-XYZ color system to DIN color system consists of the DIN 6164 method combined with the manual reading method. However, the DIN 6164 method cannot be used for the edges of a chromaticity diagram. The manual reading method can read all areas in a chromaticity diagram; however, it is too inefficient to convert large quantities of data. This study builds on the manual reading method to create a new method entitled the program reading method. Upon comparing the relative error, absolute error and conversion times of all methods, it was determined that the program reading method achieved higher accuracy than that of the manual reading method. The maximum relative error of the program reading method was 3.24%; however, the conversion time for each sample was 0.07 s, which was 3.5 times slower than that of the DIN 6164 method. Based on these findings, this study proposes an automatic conversion method that combines the strengths of both approaches: the DIN 6164 method to be used for interpolable areas and the program reading method to be used for areas that cannot be interpolated. The automatic conversion method outlined in this study provides an efficient, precise and fast way to convert a CIE-XYZ color system to a DIN color system.

A web-hosted online experiment was previously developed to find the visual difference between four reproduction gamuts using direct magnitude estimation (Proc. IS&T 29th Color and Imaging Conf, 2021:317–322). In order to increase the size of the data set, but without overburdening observers, a modular approach was adopted. The original methodology was therefore extended across 10 linked sub-experiments to make comparisons between some 36 gamuts, which were designed to exhibit a variety of different gamut shapes, contrast ratios, and substrate colors within the constraints of a desktop display. In addition to each set of test images, a common normalization set was included in all sub-experiments in order to adjust each observer's choice of modulus to a global average observer, and thus combine the results into a larger data set. Finally, an interval scale was inferred from the normalized magnitude data using a categorical judgment approach to calculate scale values. The fitted data revealed a power function close to a square-root between the interval and magnitude scales.

Accurately assessing the color quality of printed products becomes intricate  when optical brightening agents (OBAs) are introduced in papers, as diverse interactions occur among different ink pigments and papers containing OBAs due to variations in ink formulation chemistries. Specifically, alkali-based pigments, commonly used as spot colors, are carefully formulated to ensure consistency across production batches. The presence of OBAs, which absorb ultraviolet light and emit it in the visible spectrum, significantly affects  color perception and accuracy on paper when interacting with these inks. This research marks an initial investigation into how OBAs in paper influence the color accuracy of five distinct alkali-based spot color paste inks using a Little Joe ink proofer. The research examines the physical, optical, and colorimetric  characteristics of two paper samples-one with OBA and one without- and analyzes the colorimetric changes occurring during the ink drying process. The results indicate that reflex blue, purple, and violet spot colors achieved acceptable delta E (ΔE₀₀) value of below 3 on non-OBA paper, with rubine red being on the borderline at 3.1 after 48 h. In contrast, purple, rhodamine red and violet achieved acceptable ΔE₀₀ below 3 on high OBA paper. The distinct behavior exhibited by certain inks led to the conclusion that achieving a consistent  proofing procedure across diverse alkali-based ink formulations is impractical.

In this exploratory study, we delved deeply into the intricate interplay of color choices within AI-generated and human-designed posters, analyzing a sample of 120 instances from each category. While it is suggested that human designers may integrate cultural, emotional, and situational contexts into their creations, AI models largely base their selections on vast datasets and pattern recognition. Although AI exhibited prowess in replicating established design parameters, the study underlined the importance of critically assessing its outputs. The quantitative analysis illuminated overarching similarities in primary color selections. However, the AI's diversity in color remains less concentrated than that of human, suggesting a gap in the AI's capacity to match human expertise in color proportioning and distribution. As AI continues to evolve, it is crucial to discern its capabilities and potential limitations in the design domain, ensuring it augments human creativity rather than supplanting it. Notably, the research refrains from seeking human validation, aiming instead for an objective, data-driven reflection on the convergences and divergences between AI-generated and human designs.

We present the results of a series of three brightness-matching experiments which include a key refinement in this established psychophysical method. Constraining the chroma difference between pairs of stimuli matched in brightness allows us to use a novel calculus-based approach to building a model of the brightness of chromatic visual stimuli and the Helmholtz-Kohlrausch effect. The proposed models, compatible with the CIECAM16 color appearance model and CIELAB color space, are compared to other models of the Helmholtz-Kohlrausch effect on these data and other past brightness-matching studies. The proposed CIECAM16-based model demonstrates the overall best performance on predicting the Helmholtz-Kohlrausch effect in four newer data sets but overpredicts the weaker effect reported in three older data sets. The potential experimental factors in this divide between new and old studies are also discussed.