Color Science

The need for an efficient technique for compression of Images ever increasing because the raw images need large amounts of disk space seems to be a big disadvantage during transmission & storage. Even though there are so many compression technique which is faster, memory efficient and simple surely suits the requirements of the user. This paper consists of review of some of the color image compression techniques. I. Introduction It is used specially for the compression of images where tolerable degradation is required. With the wide use of computers and consequently need for large-scale storage and transmission of data, efficient ways of storing of data have become necessary. With the growth of technology and entrance into the Digital Age, the world has found itself among a vast amount of information. Dealing with such huge information can often present difficulties. Image compression is minimizing the size in bytes of a graphics file without degrading the quality of the image to an...

The need for an efficient technique for compression of Images ever increasing because the raw images need large amounts of disk space seems to be a big disadvantage during transmission & storage. Even though there are so many compression technique which is faster, memory efficient and simple surely suits the requirements of the user. This paper consists of review of some of the color image compression techniques.

A classic photographic task is the mapping of the potentially high dynamic range of real world luminances to the low dynamic range of the photographic print. This tone reproduction problem is also faced by computer graphics practitioners who map digital images to a low dynamic range print or screen. The work presented in this paper leverages the time-tested techniques of photographic practice to develop a new tone reproduction operator. In particular, we use and extend the techniques developed by Ansel Adams to deal with digital images. The resulting algorithm is simple and produces good results for a wide variety of images.

Few tone mapping operators (TMOs) take color management into consideration, limiting compression to luminance values only. This may lead to changes in image chroma and hues which are typically managed with a post-processing step. However, current post-processing techniques for tone reproduction do not explicitly consider the target display gamut. Gamut mapping on the other hand, deals with mapping images from one color gamut to another, usually smaller, gamut but has traditionally focused on smaller scale, chromatic changes. In this context, we present a novel gamut and tone management framework for color-accurate reproduction of high dynamic range (HDR) images, which is conceptually and computationally simple, parameter-free, and compatible with existing TMOs. In the CIE LCh color space, we compress chroma to fit the gamut of the output color space. This prevents hue and luminance shifts while taking gamut boundaries into consideration. We also propose a compatible lightness compression scheme that minimizes the number of color space conversions. Our results show that our gamut management method effectively compresses the chroma of tone mapped images, respecting the target gamut and without reducing image quality.

Background: Recent evidence in systems neuroscience suggests that lighting conditions affect the whole chain of brain processing, from retina to high-level cortical networks, for perceptual and cognitive function. Here, visual adaptation levels to three different environmental lighting conditions, (1) darkness, (2) daylight, and (3) prolonged exposure to very bright light akin to sunlight, were simulated in lab to investigate the effects of light adaptation levels on classic cases of subjective contrast, assimilation, and contrast-induced relative depth in achromatic, i.e., ON-OFF pathway mediated visual configurations. Methods: After adaptation/exposure to a given lighting condition, configurations were shown in grouped and ungrouped conditions in random order to healthy young humans in computer-controlled two-alternative forced-choice procedures that consisted of deciding, as quickly as possible, which of two background patterns in a given configuration of achromatic contrast appeared lighter, or which of two foreground patterns appeared to stand out in front, as if it were nearer to the observer. Results: We found a statistically significant effect of the adaptation levels on the consciously perceived subjective contrast (F(2,23) = 20.73; p < 0.001) and the relative depth (F(2,23) = 12.67; p < 0.001), a statistically significant interaction between the adaptation levels and the grouping factor (F(2,23) = 4.73; p < 0.05) on subjective contrast, and a statistically significant effect of the grouping factor on the relative depth (F(2,23) = 13.71; p < 0.01). Conclusions: Visual adaption to different lighting conditions significantly alters the conscious perception of contrast and assimilation, classically linked to non-linear functional synergies between ON and OFF processing channels in the visual brain, and modulates the repeatedly demonstrated effectiveness of luminance contrast as a depth cue; the physically brighter pattern regions in the configurations are no longer consistently perceived as nearer to a conscious observer under daylight and extreme bright light adapted (rod-saturated) conditions.

The term colour constancy is not defined in the CIE International Lighting Vocabulary, and has been understood differently by different authors, some of whom hold that it should not be used at all. For this article I define colour constancy as the relative stability of the colour we perceive as belonging to an object under varying viewing conditions, including varying illumination. In this sense, colour constancy is the way in which we experience the ability of our visual system to arrive at a relatively consistent estimate of overall spectral reflectance under varying viewing conditions
Colour constancy is normally very high under varying intensities of the same illumination, and diminishes under illumination differing in perceived colour. However, even under quite strongly coloured illumination, the degree of colour constancy our visual system achieves can be remarkable compared to the variation in the stimulus available to it. Paradoxically, the automatic mental processing that enables colour constancy in our perception of most objects in the world can result in dramatic failures of colour constancy in our perception of areas of images, and it's precisely the high level of colour constancy we usually experience, especially under varying intensities of the same illumination, that leads us to think of object colours as fixed, intrinsic properties of objects, and so to find these failures of colour constancy in our perception of image areas so alarming.

The article presents the results of the research carried out on the material of texts of artistic
and advertising discourses. The study aimed to identify and describe the functionality
of foliage colour descriptions, particularly their activity and productivity in creating new
colour terms, based on a reconstructed segment of the colour concept sphere within the floral
space of the Russian language. This is relevant to the field of colour linguistic, which seek to
create as complete a description as possible of the Russian language’s color concept sphere. To
achieve this goal, several methods were used (continuous sampling, descriptive and analytical
processes, contextual, method of quantitative data processing) to address the following
objectives: 1) to determine the quantitative and qualitative composition of colour terms
significant in the perception and visualisation of foliage in the prose of Konstantin Paustovsky,
a master of the artistic prose; 2) to reveal the specificity of Paustovsky’s colour-related
writing style through the analysis of foliage colour descriptions functioning in his artistic text;
3) to identify the functional potential of foliage descriptions realised in fiction and advertising
text; 4) to establish the composition and function of advertising colour terms based on
colouristic descriptions of foliage. The main results of this polydiscursive research include the
identification and description of: 1) the register of colour terms used by Paustovsky to visualize
foliage, of which 26 units belong to the core vocabulary, and more than 30 units expand the colour
and light range; 2) the dominant colour (yellow), reflecting K. Paustovsky’s individual perception;
3) the correlation between the Paustovsky’s colour preferences in foliage visualization and the
Russian-language colour standard; 4) the set of meanings conveyed by the colour terms; 5)
the stylistic diversity of colour terms; 6) the characteristics of Paustovsky’s colour-related
writing style; 7) the functionality of colour terms identified in the fiction text; 8) the mechanism
by which colour terms are produced within both fiction and advertising text, based on coloristic
description of foliage. The study concludes that the obtained results are significant for
describing both the individual colour picture of the world of Paustovsky, and for reconstructing
the colour concept sphere of the floral space of the Russian language. Furthermore, the
productivity of this polydiscursive study of the colour concept sphere allows for the recording
and inventory of the process by which colour terms are created, and also for the explication
of the foundations for their creation and use.

Résumé : Un bandeau noir peint sur le pourtour des murs de l'église et sur lequel figurent les armoiries seigneuriales, appelé litre, révèle un dispositif funéraire. Ce rite fut aboli avec la Révolution, effacé et oublié, il constitue aujourd'hui un enjeu crucial pour la restauration, les monuments historiques, bref notre mémoire. Nous analysons ici l'histoire du droit de litre en relation à l'espace sacré dans sa dimension politique, sociale et anthropologique. Le noir en tant que couleur de deuil renvoie à l'irreprésentable. Trait ultime, il annonce justement l'espace de l'abstraction. Mots-clés : : anthropologie des image, art et histoire, représenter le deuil, restauration, vie et mort des images, trait ultime de l'abstraction

This document presents the full theoretical, mathematical, optical, biological, and genetic foundation for the Legion GEN RAY system — an AI-driven photonic framework capable of identifying, analyzing, and eliminating harmful genetic sequences using light and consciousness modulation. It includes cross-disciplinary analysis in English and Uzbek with detailed formula derivations, physical and genetic interpretations, and a resonance-based healing mechanism guided by the ψ parameter of conscious intention.

High dynamic range (HDR) displays are be-coming more common, which has given rise to a number of reverse tone mapping tech-niques. The goal of these techniques is to ex-pand the dynamic range of all the existing low dynamic range content to fit that of these dis-plays. ...

In vision science, colours such as red, yellow, blue, and white are regarded, not as physical properties as such, but as perceptions of physical properties created by our visual system. Yet colours certainly seem to us to be physically located outside ourselves in objects and in light. In this presentation I’ll examine how this perceived physicality of colour arises and how it misleads us into thinking that when we mix coloured paints and lights we are mixing their colours.

Jizzax davlat pedagogika universiteti, Matematika va informatika yo'nalishi 5kurs talabasi Annotatsiya: Ushbu maqolada tekislikdagi harakat tushunchasi, uning eng sodda turlari va analitik ifodasi ko'rib chiqiladi. Geometriyada harakat deganda, tekislik yoki fazodagi barcha nuqtalar orasidagi masofani saqlovchi o'zgarishlar tushuniladi. Maqolada harakatning asosiy turlariparallel siljish, aylanish va simmetriya akslantirishlari batafsil tahlil qilinadi. Shuningdek, ushbu harakatlarning analitik tavsifi, ya'ni koordinatalar yordamida ifodalanishi ham ko'rib chiqiladi. Harakatlarning matematik modellari va ularning amaliy qo'llanilishi geometriya, fizika va kompyuter grafikasi kabi sohalarda muhim ahamiyat kasb etadi. Mazkur maqola tekislikdagi harakatning nazariy asoslarini tushunish va ularning real dunyodagi qo'llanilishiga doir bilimlarni kengaytirishga xizmat qiladi. Kalit so'zlar: Tekislikdagi harakat, geometrik transformatsiyalar, izometriya, parallel ko'chirish, aylanish harakati, akslantirish, transformatsiyalarning analitik ifodasi, koordinatalar o'zgarishi, matritsalar yordamida ifodalash, affin o'zgarishlar. Maktab geometriya kursida eng sodda almashtirishlar bilan tanishish ko'zda tutiladi, ular: parallel ko'chirish, simmetriya burish va o'xshash almashtirishlardan iborat. Parallel ko'chirish, simmetriya va burish barchasi adabiyotlarda bitta «harakat», yoki «siljitish» yoki «izometriya» deb aytiladi. 1-ta'rif. Tekislikning ixtiyoriy ikki nuqtasi orasidagi masofani o'zgartirmaydigan almashtirish «harakat» yoki «izometriya» deyiladi. Harakatni L orqali belgilaymiz. L harakat bo'lsa, tekislikning har qanday ikki M,N nuqtasi uchun ρ(M,N) =ρ(L(M), L(N)) (M 1 = L(M) N 1 = L(N)

Annotatsiya. Ushbu maqolada bugungi kunda yirik shahar ko'chalarida yuzaga kelayotgan tirbandliklarning asosiy sabablaridan biri chorrahalarda svetoforning ishlash rejimlari transport oqimi qatnoviga muvofiqlashtirilmaganligi oqibatida yuzaga kelayotganligi haqida so'z boradi. Chorrahalardagi tirbandliklar harakat ishtirokchilarining vaqti olinishiga, atrof-muhit ifloslanishining oshishi va tirbandliklarning kuchayishiga olib keladi. Tirbandliklarni bartaraf etishning mavjud usullariga transport oqimini boshqarishda zamonaviy innovotsion texnologiyalardan foydalanish va infratuzilmani o'zgartirish kabi tadbirlarni amalga oshirish kiradi. Shuningdek, chorrahalarda svetoforlar ish taktini optimallashtirishning asosiy yondashuvlari va usullari, transport vositalarining harakat jadalligini aniqlash, hisoblash formulalari ko'rsatib o'tilgan hamda amaliy tavsiyalar berilgan. Аннотация. В данной статье говорится о том, что одной из основных причин пробок, возникающих сегодня на улицах крупных городов, является то, что режим работы светофоров на перекрестках не соответствует с потоком транспортных средств. Пробки на перекрестках приводят к задержкам движения, увеличению загрязнения окружающей среды и увеличению заторов на дорогах. Существующие методы уменьшения заторов включают использование современных инновационных технологий в управлении транспортными потоками и реализацию таких мер, как изменение инфраструктуры. Кроме того, были показаны основные подходы и методы оптимизации такта светофоров на перекрестках, определения скорости транспортных средств, формулы расчета и даны практические рекомендации. Annotation. This article states that one of the main reasons for traffic jams that occur today on the streets of large cities is that the operating modes of traffic lights at intersections do not correspond with the flow of vehicles. Congestion at intersections leads to traffic delays, increased pollution and increased traffic congestion. Existing methods to reduce congestion include the use of modern innovative technologies in traffic management and the implementation of measures such as infrastructure changes. In addition, the main approaches and methods for optimizing the timing of traffic lights at intersections, determining the speed of vehicles, calculation formulas were shown, and practical recommendations were given. Tayanch so'zlar: chorraha, shahar infratuzilmasi, chorraha, optimallashtirish, tirbandlik, piyoda, haydovchi, svetofor, jadallik, tsikl, harakat xavfsizligi. Ключевые слова: перекрёсток, городская инфраструктура, оптимизация перекрёстка, движение транспорта, пешеход, водитель, светофор, скорость, цикл, безопасность дорожного движения.

In the ideation phases of any design process, designers usually establish conceptual parallels between the creative ideas of the project and colour as a visual language, through colour meaning and associations. However, translating abstract or textual concepts to colour selection can be very challenging when dealing with complex or sophisticated meaning associations without physical or concrete visual referents to relate to. At the same time, hue has traditionally been considered the most salient descriptor of colour and colour–meaning associations, as much of what is commonly termed the "psychology of colour" has organized emotional responses to colour, mainly through a hue paradigm. In recent years, several studies have demonstrated that value and saturation have particularly strong meaning connotations and consistent effects on emotions. While models of colour-concept association based on hue alone may work for single-colour applications, they do not lend
themselves well to design contexts where multiple colours are used simultaneously, such as environmental design. The paper presents the Colour Meaning Matrix (CMM), a practical tool to guide the selection of colours to represent conceptual associations based on semantic polar differentiation. The tool provides guidelines and suggestions to relate concepts to the scales of hue, but most importantly, lightness and saturation for the colour-concept association, allowing designers to select colours that convey the intended emotional and contextual meanings. The Colour Meaning Matrix has been tested in didactic contexts of higher education in design, with more than 300 students in two countries in Europe and Latin America.

Ushbu o‘quv qo‘llanma 60210600 – Grafika (Dastgoh va kitob grafikasi) taʼlim yo‘nalishi talabalariga Rangshunoslik va kompozitsiya asoslari” fani uchun ishlab chiqilgan bo‘lib, unda rang, uning xususiyatlari, kolorit, kompozitsiya vositalari, badiiy obraz, oltin kesim, kompozitsiya yechimlari kabi masalalar qamrab olingan. Mavzularni ochib berish uchun zamonaviy axborot texnologiyalaridan foydalanilgan. O‘quv qo‘llanma nazariy qism, amaliy topshiriq, interaktiv havola,  online test va taqdimotlardan iborat.

TV-2160 128 B.3.3 Placement of the TV-2160 Probe 129 C Tristimulus Measurements 130 C.l Introduction 130 C.l.l Precision 130 C.1.2 Accuracy 131 C.2 Repeatability 132 C.3 Integration Time, Area and Noise C.3.1 Detection of single emissions C.3.2 Integration of several emissions C.3.2.1 Integration of noise C.3.2.2 Synchronization of measurement

Este artigo aborda a importância que a humanização do ambiente hospitalar pode causar na recuperação do paciente, auxiliando seu processo de cura. Apresenta algumas soluções arquitetônicas para promover a humanização, como o uso de cores, o controle da iluminação, o contato com a natureza e a personalização dos espaços, visando proporcionar ao ambiente hospitalar um valor mais humano, aproximando-se da vida do paciente e afastando-se do caráter unicamente institucional.

The Cimento academicians investigated the colour change of liquids
treated with acids and alkali. These experiments were carried out after the release of works revealing the trade secrets of dyers and other craftsmen working with colours e.g. Antonio Neri’s L’Arte Vetraria (1612)) and, interestingly, before the publication of Robert Boyle’s Experiments and Considerations Touching Colours (1664). Moreover, though the
dedicated chapter in Saggi di naturali esperienze (1667) is rather short and understudied, a marginal gloss hints that many more similar experiments were carried out and intended for publishing separately. This essay aims to contextualise their experimental agenda on colour change within its historical framework, to present the sorts of test they investigated,
including the unpublished material, and what kind of conclusions can be drawn about their work on this subject matter.

Colour has always fascinated scientists, artists and philosophers, but only in 1931 the Commission Intérnationale de l'Eclairage (CIE) could propose a quantitative evaluation of colour, based on the concept of 'colour temperature' (CT). The historical path that leaded to the CIE method had started much earlier, with Newton, and pursued with Grassmann and Maxwell. The final thrust for a mathematisation of colour came from the economic and social need for a standardized system of lighting. Fundamental research necessary for standardization came from an interesting mixing of research centers of the Anglo-Saxon world: in the United States by the National Bureau of Standards and the National Electric Lamp Association Laboratory; in the UK by the National Physical Laboratory and Imperial College, London. CIE's rules are still a fundamental reference in several industrial and research fields (electronics, dyes, food, cultural heritage). However, CT is not devoid of criticisms: it contradicts common use ('hot' colours exhibit lower CTs as compared to 'cold' colours); it is strictly conventional (a LED with CT~2700 K has an active area at 350 K).

This study aimed to estimate the number of distinct tooth colors using a large dataset of in-vivo CIELAB measurements. It further assessed the coverage error (CE) and coverage error percentage (CEP) of commonly used shade guides and determined the number of shades needed for an ideal guide, using the Euclidean distance (ΔEab) and thresholds for clinical perceptibility (PT) and acceptability (AT) as evaluation criteria. Methods: A total of 8153 untreated maxillary and mandibular anterior teeth were measured in vivo using calibrated dental photography. Cardinality was applied to determine the number of unique natural tooth colors. The CE and CEP were calculated for the Vita Classical and Vita 3D-Master shade guides, while the cardinality method was also used to estimate the number of shades required to adequately cover the estimated gamut of natural tooth colors. Results: The cardinality analysis revealed 1173 unique natural tooth colors. The CE for the Vita Classical shade guide was 4.1 ΔEab, with a CEP of 75 % beyond AT, while the 3D-Master shade guide had a CE of 3.3 ΔEab and a CEP of 70 % beyond AT. Based on cardinality computation, 92 discrete shades are required to adequately cover the estimated gamut of natural tooth colors with a CE of 1.2 ΔEab and CEP of 0.3 % beyond AT. Conclusions: Cardinality computations estimated 1173 unique tooth colors while 92 discrete shades are estimated for full coverage. Such a number is impractical for physical shade guides, but new digital tools and 3D printing may offer future solutions. Both, the Vita Classical and 3D-Master shade guides do not fully represent the range of natural tooth colors. Clinical significance: This study highlights the limitations of existing shade guides and underscores the potential for new developments.

The use of light as a narrative device and as a means of storytelling is becoming increasingly important in architectural lighting design as the focus shifts more and more to the user experience. This master's thesis deals with the topic of narrative lighting in order to develop an awareness of its impact dimensions. To gain insights, the following research question is posed: How does lighting influence the reception process in the recipient? What are the dimensions of narrative lighting? The aim is to open up an understanding of the narrative possibilities of lighting with a focus on humanistic factors. To answer the research question, a literature review will be conducted to develop an understanding of the factors that make up stories and the levels at which light can influence and support a narrative process. Additional insights into how other story-based media forms use light as a narrative device will help to broaden the framework. The objective of this master's thesis is to explore principles and approaches from other disciplines and media and to examine their relevance and applicability in architectural lighting. Can these findings also be used for architectural lighting and if so, what needs to be considered? An objective insight into how recipients are influenced by light in the narrative process is to be gained through an image survey. Subsequently, questions will be answered with the help of the framework in order to develop theses on the narrative dimensions of light. These dimensions are questioned with regard to their transfer to the field of architecture. The analysis shows that the findings of narrative lighting have a different relevance in media based on stories than in architectural space. Requirements of architectural lighting are subject to functionality, standards and norms. The results show that the differences between the two areas result from the fundamentally different initial situation. Despite the dissimilarities, however, both areas also have commonalities, which can be identified as the application of common lighting principles. The dimensions of narrative lighting are already partly applied in the areas of architectural lighting design, but they are named and defined differently.

A good but neglected place to start a course on colour is to ask what kinds of things we perceive as having colours. In this short video I describe a simple exercise that I use to introduce three important kinds of colours: colours perceived as belonging (1) to objects themselves, (2) to the light falling on objects, and (3) to the light reaching our eyes from objects. A version of this exercise along with many more colour exercises by other members of the ISCC/AIC Colour Literacy Project (CLP) are now available on the CLP website.

The effect of different types of nano silica (nano cristobalite, hydrophilic nano silica and hydrophobic nano silica) on some properties of two component polyurethane clear coat has been studied. Rheometric studies at low shear rates shows a shear thinning behavior in ...

يهللرگرز ناميا 1 ، رهچونم يناسارخ 2 * ، يلع رغصا غابص يناولا 2 داجس ، ينايك 3 1 ـ سانشراك ،دشرا ينف هدكشناد ،بونج نارهت دحاو يملاسا دازآ هاگشناد ،يسدنهم ،ناريا ،نارهت يتسپ قودنص : 4435 11365 2 ـ ،رايداتسا هدكشهوژپ گنر و ،رميلپ هاگشناد يتعنص ريبكريما ،ناريا ،نارهت ، يتسپ قودنص : 4413 15875 3 ـ ،دشرا سانشراك گنر و رميلپ يسدنهم هدكشناد ، هاگشناد يتعنص ا ريبكريم ،ناريا ،نارهت ، يتسپ قودنص : 4413 15875 :تفايرد خيرات 25 / 9 / 92 :شريذپ خيرات 20 / 7 / 93 :زا يكينورتكلا تروص هب سرتسد رد 20 / 12 / 1393

In order to improve our knowledge of cation-anion interactions in ionic liquids, we optimized the 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMImBF4]), and their interactions with CO2, with a focus on structural properties and vibrational behavior relevant to chemical applications such as carbon capture. By using density functional theory (DFT), the structures of the cation, anions, and cation-anion ion pairs of [EMImBF4] with CO2 were optimized. Vibrational spectroscopy was employed to emphasize structural properties, and vibrational frequencies of EMImBF4 and EMImBF4-CO2 (monomer) compounds were calculated. The scaled values were compared to experimental far-infrared and far-infrared Raman spectra to validate the theoretical findings.The study identified the most stable geometries of [EMImBF4] and [EMImBF4]-CO2 interactions, showing specific vibrational modes upon interaction with CO2 that align well with experimental data. These insights highlight the potential of [EMImBF4] in gas separation and capture, demonstrating its unique physicochemical properties and reinforcing the importance of understanding IL-CO2 interactions for developing efficient carbon capture technologies.

In order to improve our knowledge of cation-anion interactions in ionic liquids, we optimized the 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMImBF4]), and their interactions with CO2, with a focus on structural properties and vibrational behavior relevant to chemical applications such as carbon capture. By using density functional theory (DFT), the structures of the cation, anions, and cation-anion ion pairs of [EMImBF4] with CO2 were optimized. Vibrational spectroscopy was employed to emphasize structural properties, and vibrational frequencies of EMImBF4 and EMImBF4-CO2 (monomer) compounds were calculated. The scaled values were compared to experimental far-infrared and far-infrared Raman spectra to validate the theoretical findings.The study identified the most stable geometries of [EMImBF4] and [EMImBF4]-CO2 interactions, showing specific vibrational modes upon interaction with CO2 that align well with experimental data. These insights highlight the potential of [EMImBF4] in gas separation and capture, demonstrating its unique physicochemical properties and reinforcing the importance of understanding IL-CO2 interactions for developing efficient carbon capture technologies.

ObjectiveTo investigate the influence of opacity and color of luting cements on the final shade of metal‐free restorations.Materials and MethodsFive resin cement colors in combination with four different thicknesses of CAD/CAM ceramic materials were tested, and a composite substrate was used as dentin color reference (n = 3). Specimen color was measured with a spectrophotometer equipped with an integrating sphere before and after cementation (CIELAB). Cement and ceramic color and opacity (TP) were assessed by measuring the tested ceramic thickness as a 1‐mm thick disk for each of the cement shades. The differences in color were evaluated (ΔE00). Data were statistically analyzed by a Two‐Way ANOVA followed by the Tukey Test for post‐hoc comparison (P &lt; .05) and multiple comparison Pearson&#39;s test (P &lt; .05); the acceptability and perceptibility threshold were evaluated.ResultsStatistically significant influence was found for factors ceramic thickness and cement shade (P &lt; ...

This chapter delves into the interplay between colour and memory from
a dual perspective. The first perspective explores how colour is a potent
conduit for human memory, fostering object recognition, heightening attention, and triggering emotional responses – all pivotal processes for enhancing memory performance. Also, it reflects on the portrayal of memory and flashbacks in the collective imagination, particularly in cinema, where black-and-white depictions have been the norm. However, research indicates that memory recognition is notably more accurate for coloured stimuli than their black-and-white counterparts. The second perspective probes into the fleeting and subjective nature of colour memory. It uncovers humans’ challenges when precisely matching or recalling specific colours, even mere seconds after perceiving them. This exploration elucidates how certain colours are more indelible in memory than others and how properties like hue, lightness, and saturation may impact this phenomenon. Also, the concept of “memory colour” – the quintessential colour associated with canonical objects like the yellow of a banana or the green of grass – is presented along with its complexities
and advantages. Lastly, some concepts discussed are illustrated using
the chromatic visual atlases derived from Mnemosphere’s Open Call for Images.

Ringvorlesung KunstMachen, Technische Universität Berlin, 13 January 2021

Unser Projekt “Farbordnungen, Farbmittel und Farbterminologie” wird die Verbin-dungen zwischen Farbnamen und bestimmten Farbmitteln untersuchen. Histori-schen Maltraktate und Handbücher wiederholen häufig und interessanterweise die gleichen, teilweise rätselhaften, Farbtermini, wie z. B. Haarbraun.  Viele Auto-ren sprechen davon, und man würde sich fragen, ob dies möglicherweise eine be-kannte Pigmentmischung unter Malern und anderen Handwerkern war. Um solche Rätsel zu lösen, helfen uns dabei unter anderem historische Farbkarten, in denen diese Farbnamen von Farbmusters vertreten sind und die bisweilen mit Farbnamen und manchmal sogar mit Mischanleitungen versehen sind. Heute möchten wir die Frage von “reinen Farben” und ihren Farbmitteln in der Dreifarbenlehre nachge-hen. Vorab sei gesagt, dass wir mehr einen Einblick in die ‚Werkstatt‘ geben als dass wir schon fertige und vollständige Resultate vorstellen könnten – das Projekt ist am Anfang, und wir hoffen, Ihnen wenigstens einen Einblick in die Fragen und Materialien geben zu können, mit denen wir uns befassen.

We present a novel, end-to-end workflow for content creation and distribution to a multitude of displays that have different dynamic ranges. The emergence of new, consumer level HDR displays with various peak luminances expected in 2015 gives rise to two new research questions: (i) how can the raw source content be graded for a diverse set of displays both efficiently and without restricting artistic freedom, and (ii) how can an arbitrary number of graded video streams be represented and encoded in an efficient way. In this work we propose a new editing paradigm which we call dynamic range mapping to obtain a novel Continuous Dynamic Range (CDR) video representation, where the luminance of the video content, instead of being a scalar value, is defined as a continuous function of the display dynamic range. We present an interactive interface where CDR videos can be efficiently created while providing full artistic control. In addition, we discuss the efficient approximation of CDR vi...

Hazy images have limited visibility and low contrast. The degradation is expressed by transmission map, which is one of the most important estimates of single image dehazing. Transmission map estimation is an underconstraint problem, and lots of priors have been proposed. Among them, the dark channel prior is widely recognized. However, traditional methods have not fully exploited its power due to improper assumptions or operations, which cause unwanted artifacts. The postrefinement algorithms employed to remove these artifacts in turn undermine the merits of the prior. In this letter, a novel method for estimating transmission map by energy minimization is proposed to solve this problem. The energy function combines the dark channel prior with piecewise smoothness. The method is compared to the state-of-theart methods and shows outstanding performance.

Unique-hue spectral loci were measured under conditions of neutral adaptation as part of a study of hue-response recovery following chromatic adaptation. Four observers adjusted the wavelength of the test-field until it appeared to be neither yellow nor blue (unique green) or neither red nor green (unique yellow and blue) in randomized sessions. The results showed that there were marked individual differences and long-term drifts in the unique-hue settings over a period of a month. The variability within a session was minimal.

Crowdsourcing is a popular tool for conducting subjective evaluations in uncontrolled environments and at low cost. In this paper, a crowdsourcing study is conducted to investigate the impact of High Dynamic Range (HDR) imaging on subjective face recognition accuracy. For that purpose, a dataset of HDR images of people depicted in high-contrast lighting conditions was created and their faces were manually cropped to construct a probe set of faces. Crowdsourcing-based face recognition was conducted for five differently tone-mapped versions of HDR faces and were compared to face recognition in a typical Low Dynamic Range alternative. A similar experiment was also conducted using three automatic face recognition algorithms. The comparative analysis results of face recognition by human subjects through crowdsourcing and machine vision face recognition show that HDR imaging affects the recognition results of human and computer vision approaches differently.

Standards play an important role in providing a common set of specifications and allowing interoperability between devices and systems. Until recently, no standard for High Dynamic Range (HDR) image coding had been adopted by the market, and HDR imaging relies on proprietary and vendor specific formats which are unsuitable for storage or exchange of such images. To resolve this situation, the JPEG Committee is developing a new coding standard called JPEG XT that is backwards compatible to the popular JPEG compression, allowing it to be implemented using standard 8-bit JPEG coding hardware or software. In this paper, we present design principles and technical details of JPEG XT. It is based on a two-layers design, a base layer containing a Low Dynamic Range (LDR) image accessible to legacy implementations, and an extension layer providing the full dynamic range. The paper introduces three of currently defined profiles in JPEG XT, each constraining the common decoder architecture to a subset of allowable configurations. We assess the coding efficiency of each profile extensively through subjective assessments, using 24 naïve subjects to evaluate 20 images, and objective evaluations, using 106 images with five different tone-mapping operators and at 100 different bit rates. The objective results (based on benchmarking with subjective scores) demonstrate that JPEG XT can encode HDR images at bit rates varying from 1.1 to 1.9 bit/pixel for estimated mean opinion score (MOS) values above

Recent advances in high dynamic range (HDR) capture and display technologies have attracted a lot of interest from scientific, professional, and artistic communities. As in any technology, the evaluation of HDR systems in terms of quality of experience is essential. Subjective evaluations are time consuming and expensive, and thus objective quality assessment tools are needed as well. In this paper, we report and analyze the results of an extensive benchmarking of objective quality metrics for HDR image quality assessment. In total, 35 objective metrics were benchmarked on a database of 20 HDR contents encoded with 3 compression algorithms at 4 bit rates, leading to a total of 240 compressed HDR images, using subjective quality scores as ground truth. Performance indexes were computed to assess the accuracy, monotonicity, and consistency of the metric estimation of subjective scores. Statistical analysis was performed on the performance indexes to discriminate small differences between metrics. Results demonstrated that metrics designed for HDR content, i.e., HDR-VDP-2 and HDR-VQM, are the most reliable predictors of perceived quality. Finally, our findings suggested that the performance of most full-reference metrics can be improved by considering non-linearities of the human visual system, while further efforts are necessary to improve performance of no-reference quality metrics for HDR content.

The ability of high dynamic range (HDR) to capture details in environments with high contrast has a significant impact on privacy in video surveillance. However, the extent to which HDR imaging affects privacy, when compared to a typical low dynamic range (LDR) imaging, is neither well studied nor well understood. To achieve such an objective, a suitable dataset of images and video sequences is needed. Therefore, we have created a publicly available dataset of HDR video for privacy evaluation PEViD-HDR, which is an HDR extension of an existing Privacy Evaluation Video Dataset (PEViD). PEViD-HDR video dataset can help in the evaluations of privacy protection tools, as well as for showing the importance of HDR imaging in video surveillance applications and its influence on the privacy-intelligibility trade-off. We conducted a preliminary subjective experiment demonstrating the usability of the created dataset for evaluation of privacy issues in video. The results confirm that a tone-mapped HDR video contains more privacy sensitive information and details compared to a typical LDR video.

Цветовете са около нас от появата ни на този свят. Цветът е носител на информация, на чувства, на виждането ни за красиво, на разбирането ни за добро и лошо, на живот, на принадлежност, на вдъхновение, на знания предавани от майка на дъщеря. Цветовете имат общочовешки, универсални значения, предизвикват идентични емоции и асоциации и се свързват с аналогични символи и ритуали в различни части на света. От праисторически времена човекът се е стремил към красивото. Украсявайки тялото и дрехите си е показвал своята принадлежност и място в обществото. Преплитайки всички багри в една черга българката рисува пъстротата на живота, където има всичко. Втъкани са работата със земята, рожбата, либето, болката, топлото слънце, животворния дъжд - черно, червено, оранжево, жълто, зелено, синьо във всичките им нюанси.
Colours have been around us since our appearance in this world. Colour is a carrier of information, of feelings, of our vision of beauty, of our understanding of good and bad, of life, of belonging, of inspiration, of knowledge passed down from mother to daughter. Colours have common human, universal meanings, evoke identical emotions and associations, and are associated with similar symbols and rituals in different parts of the world. Since prehistoric times, man has aspired to the beautiful. By decorating his body and clothes, he showed his belonging and place in society. Interweaving all the colours in one rug, the Bulgarian woman paints the motley of life, where there is everything. Work with the earth, the child, the pain, the warm sun, the life-giving rain - black, red, orange, yellow, green, blue in all their shades are all woven in.

The aspect of colour theory most fundamental for artists is the classification of colours into ordered systems, because these systems serve as a conceptual framework for solving colour problems of all kinds. This lecture looks at the diversity of colour order systems that have been available to artists both before and after the late 19th century revolution in our understanding of colour.

Effective thinking and communication about colour depends on the existence of a mutually agreed and unambiguous vocabulary. For fundamental terms relating to what colour is and how it can be described and specified, by far the most comprehensive and authoritative standard is the International Lighting Vocabulary of the International Commission on Illumination (CIE, 2011)1. However the verbal CIE definitions, including those of the six fundamental perceived colour attributes of hue, brightness, lightness, colourfulness, chroma and saturation, can be difficult for non-specialists to understand without additional explanation and illustration. In addition, the CIE definitions do not cover many terms relating to applied colour that are important to artists and designers. For such terms we often must acknowledge a number of conflicting usages associated with different traditions.

To celebrate International Colour Day 2017 the NSW Division of the Colour Society of Australia produced an exhibit on the theme Visual Dictionary of Colour at the National Art School, Darlinghurst, Sydney. The bulk of the works to be exhibited were produced by students at the National Art School in the Visual Dictionary of Colour workshop that I conducted there in Margaret Olley Drawing Week at the start of the academic year. The brief of the workshop was to contribute to an exhibition illustrating specific colour-related terms using media of the students’ choice, including drawing, painting, photography, digital illustration and 3D models. The student works were supplemented with some digital illustrations made by myself for a chapter on Colour Spaces for the forthcoming Routledge Handbook of Philosophy of Colour, and for my website The Dimensions of Colour (www.huevaluechroma.com), and also with student exercises and teaching demonstrations associated with the history of the National Art School.

The CIE terminology of colour reflects a scientific orthodoxy that regards the attributes of colour as psychological, but regards the particular colours that we see as intrinsic in lights and objects as neither purely psychological nor purely physical, but as ways of seeing a physical property in terms of the psychological attributes of colour. Specified by tristimulus values as a psychophysical colour, the physical property that a “standard observer” sees as the intrinsic colour of a light/ object is a spectral power distribution/spectral reflectance belonging to an objective, measurable but species-specific class united by the response evoked in the human visual system. (On a very fine-grained level these classes are likely to be individual-specific.)
Colours seen as belonging to objects can be described in terms of hue, lightness, and chroma, or various alternative sets of three attributes. Colours seen as belonging to lights, including the light reflected to the eye by an object at any given point, can be described in terms of hue,
brightness, and either colourfulness or saturation. Three dimensions suffice to describe any colour, but most appearances can be seen as involving more than one colour and thus more than three colour attributes.
Spaces of psychophysical colours can be of the “recipe” type, classifying colours according to physical, imaginary, or theoretical components, or of the psychometric type, classifying colours using dimensions intended as measures of various psychological attributes of colour. The variety
of alternative attributes and the variety of measures available to quantify these attributes together contribute to the great diversity of psychometric colour spaces.

This webinar is based on my two-part paper on the fundamental elements of colour that had been recently accepted for the Journal of the International Colour Association or AIC. Part One of the paper, is the main focus of the webinar, presents an extended answer to the question "what is a colour?" by reviewing the connections between colour stimuli, colour perceptions, and colour measurement. This is followed by some selected highlights from Part Two of the paper, which focuses on an analysis of colour perception, exploring the main modes of colour appearance (as belonging to objects or lights in various ways) and perceived colour attributes (hue, lightness, and so on) and their interrelationships.

The video recording is available at https://www.youtube.com/watch?v=AtrRpGb-7FU

Colour education typically describes colour as having three attributes or dimensions, usually listed as (1) hue, (2) a term for lightness such as "value", "greyscale value", or "tone", and (3) a term for chromatic intensity, usually either "chroma" or "saturation", and generally meaning chroma as defined by the CIE. The remaining CIE-defined attributes of saturation (sensu CIE), brightness and colourfulness are rarely emphasized in colour education, despite being well-suited to the task of describing the colour appearance of illuminated objects. The writer has devised illustrations and explanations to help communicate these and related concepts during many years of teaching colour in art and design courses, and the paper presents selected examples of these that help to communicate the concepts of modes of colour appearance, brightness, colourfulness, saturation, brilliance and blackness.

Colorimetric specification of lights and objects can be a source of confusion in the broader colour community, and many find the concept of colorimetric or psychophysical "colour" to be suspect or even nonsensical. This paper reviews the connections between colour stimuli, colour perceptions, and colorimetric specifications, leading to consideration of the ontology of colour implicit in the CIE definitions of "perceived colour" and "psychophysical colour", which correspond respectively to our perceptions of colour and to the perceivable properties of lights and objects that these perceptions are based on.

This paper presents an extended consideration of the question of what colours are from a scientific perspective by reviewing the connections between colour perceptions, colour stimuli, and colour measurement. The colour of an isolated light can be understood to be the way in which we perceive the overall balance of its spectral composition relative to that of daylight; "overall" here meaning at the level of its long-, middle-and short-wavelength components, as detected by the human visual system. Our ability to detect variations in this overall balance, first demonstrated by Newton, is now understood to rely on comparison of the responses of three receptor types by the process of cone opponency. The colour perceived as belonging to an object when it is freely examined in daylight, which we tend to think of as the (seemingly) intrinsic colour of the object, can similarly be understood to be the way in which we perceive its overall spectral reflectance, again at the level of its long-, middle-and short-wavelength components, as detected by the human visual system. Colorimetric measures are designed to quantify for practical purposes precisely these human-perceiver-dependent "overall" properties of spectral distributions and spectral reflectances, by ignoring physical differences that we do not perceive as colour differences. In defining two senses of word colour, "perceived colour" and "psychophysical colour", the CIE International Lighting Vocabulary in effect expresses a pluralist ontology of colour that acknowledges that we may wish to use the word "colour" either for our perceptions of colour, or for the measurable, human-perceiver-dependent properties that dispose physically different lights or objects to appear the same colour in the same context.

With production side for the HDR video being standardized, the distribution phase is still in its infancy. Although a number of promising HDR video coding methods exist, the standardization efforts for HDR video distribution are hampered due to limited performance evaluations. This paper addresses this shortcoming by first reviewing the existing HDR video coding methods categorically. A comprehensive performance evaluation is then presented of five state-of-the-art HDR video coding methods, namely HDR-MPEG, HDR10 (PQ), HLG HDR-TV, AdaptRes and SHVC-based coding method. The evaluation was performed on a HDR video dataset considering two HDR display configurations with four objective quality measures including HDR-VDP-2.2 and HDR-VQM quality metrics. The results reveal novel observations regarding two-layer backwardcompatible HDR video coding methods indicating that these methods can provide better or similar HDR quality as in single-layer backward-compatible HDR video coding method HLG HDR-TV. Furthermore, HDR10 (PQ), the single-layer method designed for only HDR content delivery, outperforms the other evaluated methods in this work, demonstrating that best HDR quality can be achieved only without the constraint of backward compatibility. Finally, a discrepancy revealed in the performance, in terms of the HDR-VQM metric when compared to the other quality measures, is presented and its implications are discussed. Keywords Backward compatibility • HDR video coding methods • HDR video compression • HDR Video distribution • Layered coding