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71.
Colors can be characterized by three main attributes: hue, value, and saturation. But colors also exhibit other phenomenological qualities. In this study, we identify one such secondary attribute of color: perceived density. We discuss the prevalence of dense colors in Japan starting from the “48 Teas and 100 Mice” colors of the Edo period, and develop the concept of perceived density through this aspect of Japanese color preference. When vivid colors were forbidden to commoners during the Edo period, subtle variations of brownish and grayish colors were created. These colors with base tones were not salient, yet they looked dense. Muted colors with paradoxical richness are still common in Japan today. Japanese commodity design often uses muddy colors with white or gray undertones, and deep colors with black undertones. Together they form distinct groupings of relatively dense color. The perceived density of color corresponds to how dense and filled, or thin and airy a color appears. Colors of higher perceived density appear to be more packed and to have mass. Perceived density of color is unusual in that it does not have a monotonic relationship with one of the primary perceptual attributes. High apparent density is observed in a central region of an equi‐hue plane where value or saturation are at intermediate values. We consider two possible explanations of how high values of density can coincide with middling values of value and saturation: characteristics of the spectral reflectance curves, or the complexity of the neural signals that underlie the emergent property. 相似文献
72.
Xunwang Shi Xiuhan Yu Caiwen Nie Fengji Li Sam Zhang 《Ceramics International》2021,47(15):21546-21553
Color films are widely used for visual effect as well as for their functional properties. To date, however, synthesizing thin films with desired color remains challenging. In this work, AlN color films are deposited on Si wafers by precise control of the deposition time for different thickness during reactive magnetron sputtering from an Al target in Ar/N2 atmosphere. The thickness, morphology, structure, composition and color index are carefully examined by field emission scanning electron microscopy, atomic force microscopy, grazing incidence X-ray diffraction, X-ray photoelectron spectrometry and colorimeter, respectively. As the film thickness changes from 57 nm to 165 nm, the film exhibits purple, indigo, blue, green, yellow, orange and red in color. These colors repeat in the same order when the thickness goes over 165 nm. Once the thickness exceeds 467 nm, overlapping of colors takes place. The mechanisms are elucidated. 相似文献
73.
本文借助计算机中的视觉自动检测技术来测量在果实表面的着色度,并对该颜色进行了分级,进一步的对颜色进行分析与研究,进而来获得出最终的水果果实的彩色图像,进一步的分析出对应的结果。因此,在本文中,对果实表面颜色进行了全面综合的分析与研究,进而来得出对应的果实颜色分级标准和原则。 相似文献
74.
Aiming at the performance degradation of the existing presentation attack detection methods due to the illumination variation, a two-stream vision transformers framework (TSViT) based on transfer learning in two complementary spaces is proposed in this paper. The face images of RGB color space and multi-scale retinex with color restoration (MSRCR) space are fed to TSViT to learn the distinguishing features of presentation attack detection. To effectively fuse features from two sources (RGB color space images and MSRCR images), a feature fusion method based on self-attention is built, which can effectively capture the complementarity of two features. Experiments and analysis on Oulu-NPU, CASIA-MFSD, and Replay-Attack databases show that it outperforms most existing methods in intra-database testing and achieves good generalization performance in cross-database testing. 相似文献
75.
Dimming technologies have been used in liquid crystal display (LCD) products, especially for mobile applications, to reduce power consumption. It is widely known that dimming technologies tend to degrade the color accuracy. This article, however, presents that color performance of a dimmed LCD is better than a conventional one. We show a max method, one of dimming methods, converting an input digital data into higher values that have less color shift phenomenon. We propose how to compare the color performance of original and dimmed colors based on a modified standard. The average value of measured Δu′v′ of 25 dimmed colors was 0.0040, whereas that of the original colors was 0.0190. In addition, the average value of measured Δ of 25 dimmed colors was 2.40, whereas that of the original colors was 9.24. The measured results prove that the dimming technology can make LCD better in not only power consumption but also color performance. This article is the world's first report that breaks the usual stereotype on dimming technologies. This work proposes a dimmed LCD as a standard color display. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 480–485, 2014 相似文献
76.
以3种不同粒径的规格型号为CC–1250,CC–2500和CC–6000的超细Ca CO3替代20%的联苯胺黄颜料应用于ABS黄色母粒中,研究了这3种超细Ca CO3对ABS黄色母粒色彩性能的影响。结果表明,超细Ca CO3粒子的粒径越小,其对色母粒的色彩性能影响越小;由含有粒径最小的CC–6000型超细Ca CO3的色母粒所制备的ABS样板反射率曲线及明度值与未加超细Ca CO3的最为接近,且两者的色差最小;由含有CC–6000型和CC–1250型超细Ca CO3的色母粒所制备的ABS薄膜透过率曲线与未加超细Ca CO3的也最为接近。 相似文献
77.
78.
文章运用MOPAC半经验量化程序,对部分染料分子结构进行计算,然后将结果和事实相对照与比较,从而分析染料分子结构与颜色的关系,并从中总结出一些规律。 相似文献
79.
80.