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Sample records for blue-yellow color opponent

  1. P1-12: Different Double-Pulse Distinguishability Among the Luminance Opponency, the Red-Green Opponency, and the Blue-Yellow Opponency

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    Lin Shi

    2012-10-01

    Full Text Available The inter-stimuli-interval (ISI thresholds of double pulses discrimination were measured to investigate the temporal distinguishability of double pulses of the luminance opponency, the red-green opponency, and the blue-yellow opponency. Double pulses were presented randomly in one of four quadrants, defined by a central fixation cross on a CRT display controlled by the real time sequencer (RTS of the VSG system in 42-bit color mode calibrated with less than 3% display error rate of the 1931 CIE luminance and chromatic coordinate. Each pulse was of duration 6.7 msec and included a Gaussian patch with gradation of tristimulus values from the peak to the background in equal-energy-white (the luminance opponency or isoluminance (the red-green and the blue-yellow opponency configuration. Eleven observers were asked to report the number of pulses (one or two observed while ISI was adjusted by a psi method. Psychometric functions were estimated using the cumulative distribution function of the extreme value distribution. The threshold was the ISI value corresponding with the rate of 63.21% correct answer. Significant differences were found among ISI thresholds of the luminance, blue-yellow, and red-green opponency. Results supported that the temporal distinguishability of double pulses of the luminance opponency, the red-green opponency, and the blue-yellow opponency were significantly different. The difference can be explained by the impulse response functions (IRF with various first peak time among the luminance opponency, the red-green opponency, and the blue-yellow opponency.

  2. A Color-Opponency Based Biological Model for Color Constancy

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    Yongjie Li

    2011-05-01

    Full Text Available Color constancy is the ability of the human visual system to adaptively correct color-biased scenes under different illuminants. Most of the existing color constancy models are nonphysiologically plausible. Among the limited biological models, the great majority is Retinex and its variations, and only two or three models directly simulate the feature of color-opponency, but only of the very earliest stages of visual pathway, i.e., the single-opponent mechanisms involved at the levels of retinal ganglion cells and lateral geniculate nucleus (LGN neurons. Considering the extensive physiological evidences supporting that both the single-opponent cells in retina and LGN and the double-opponent neurons in primary visual cortex (V1 are the building blocks for color constancy, in this study we construct a color-opponency based color constancy model by simulating the opponent fashions of both the single-opponent and double-opponent cells in a forward manner. As for the spatial structure of the receptive fields (RF, both the classical RF (CRF center and the nonclassical RF (nCRF surround are taken into account for all the cells. The proposed model was tested on several typical image databases commonly used for performance evaluation of color constancy methods, and exciting results were achieved.

  3. Color opponent receptive fields self-organize in a biophysical model of visual cortex via spike-timing dependent plasticity.

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    Eguchi, Akihiro; Neymotin, Samuel A; Stringer, Simon M

    2014-01-01

    Although many computational models have been proposed to explain orientation maps in primary visual cortex (V1), it is not yet known how similar clusters of color-selective neurons in macaque V1/V2 are connected and develop. In this work, we address the problem of understanding the cortical processing of color information with a possible mechanism of the development of the patchy distribution of color selectivity via computational modeling. Each color input is decomposed into a red, green, and blue representation and transmitted to the visual cortex via a simulated optic nerve in a luminance channel and red-green and blue-yellow opponent color channels. Our model of the early visual system consists of multiple topographically-arranged layers of excitatory and inhibitory neurons, with sparse intra-layer connectivity and feed-forward connectivity between layers. Layers are arranged based on anatomy of early visual pathways, and include a retina, lateral geniculate nucleus, and layered neocortex. Each neuron in the V1 output layer makes synaptic connections to neighboring neurons and receives the three types of signals in the different channels from the corresponding photoreceptor position. Synaptic weights are randomized and learned using spike-timing-dependent plasticity (STDP). After training with natural images, the neurons display heightened sensitivity to specific colors. Information-theoretic analysis reveals mutual information between particular stimuli and responses, and that the information reaches a maximum with fewer neurons in the higher layers, indicating that estimations of the input colors can be done using the output of fewer cells in the later stages of cortical processing. In addition, cells with similar color receptive fields form clusters. Analysis of spiking activity reveals increased firing synchrony between neurons when particular color inputs are presented or removed (ON-cell/OFF-cell).

  4. Chromatic aberration and the roles of double-opponent and color-luminance neurons in color vision

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    Vladusich, Tony

    2007-01-01

    How does the visual cortex encode color? I summarize a theory in which cortical double-opponent color neurons perform a role in color constancy and a complementary set of color-luminance neurons function to selectively correct for color fringes induced by chromatic aberration in the eye. The theory

  5. Chromatic aberration and the roles of double-opponent and color-luminance neurons in color vision.

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    Vladusich, Tony

    2007-03-01

    How does the visual cortex encode color? I summarize a theory in which cortical double-opponent color neurons perform a role in color constancy and a complementary set of color-luminance neurons function to selectively correct for color fringes induced by chromatic aberration in the eye. The theory may help to resolve an ongoing debate concerning the functional properties of cortical receptive fields involved in color coding.

  6. Proton feedback mediates the cascade of color-opponent signals onto H3 horizontal cells in goldfish retina.

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    Kamiji, Nilton L; Yamamoto, Kazunori; Hirasawa, Hajime; Yamada, Masahiro; Usui, Shiro; Kurokawa, Makoto

    2012-04-01

    It has been postulated that horizontal cells (HCs) send feedback signals onto cones via a proton feedback mechanism, which generates the center-surround receptive field of bipolar cells, and color-opponent signals in many non-mammalian vertebrates. Here we used a strong pH buffer, HEPES, to reduce extracellular proton concentration changes and so determine whether protons mediate color-opponent signals in goldfish H3 (triphasic) HCs. Superfusion with 10mM HEPES-fortified saline elicited depolarization of H3 HCs' dark membrane potential and enhanced hyperpolarizing responses to blue stimuli, but suppressed both depolarization by yellow and orange and hyperpolarization by red stimuli. The response components suppressed by HEPES resembled the inverse of spectral responses of H2 (biphasic) HCs. These results are consistent with the Stell-Lightfoot cascade model, in which the HEPES-suppressed component of H3 HCs was calculated using light responses recorded experimentally in H1 (monophasic) and H2 HCs. Selective suppression of long- or long-+middle-wavelength cone signals by long-wavelength background enhanced the responses to short-wavelength stimuli. These results suggest that HEPES inhibited color opponent signals in H3 HCs, in which the source of opponent-color signals is primarily a feedback from H2 HCs and partly from H1 HCs onto short-wavelength cones, probably mediated by protons.

  7. Color constancy of color-deficient observers under illuminations defined by individual color discrimination ellipsoids.

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    Ma, Ruiqing; Kawamoto, Ken-Ichiro; Shinomori, Keizo

    2016-03-01

    We explored the color constancy mechanisms of color-deficient observers under red, green, blue, and yellow illuminations. The red and green illuminations were defined individually by the longer axis of the color discrimination ellipsoid measured by the Cambridge Colour Test. Four dichromats (3 protanopes and 1 deuteranope), two anomalous trichromats (2 deuteranomalous observers), and five color-normal observers were asked to complete the color constancy task by making a simultaneous paper match under asymmetrical illuminations in haploscopic view on a monitor. The von Kries adaptation model was applied to estimate the cone responses. The model fits showed that for all color-deficient observers under all illuminations, the adjustment of the S-cone response or blue-yellow chromatically opponent responses modeled with the simple assumption of cone deletion in a certain type (S-M, S-L or S-(L+M)) was consistent with the principle of the von Kries model. The degree of adaptation was similar to that of color-normal observers. The results indicate that the color constancy of color-deficient observers is mediated by the simplified blue-yellow color system with a von Kries-type adaptation effect, even in the case of brightness match, as well as by a possible cone-level adaptation to the S-cone when the illumination produces a strong S-cone stimulation, such as blue illumination.

  8. Contrast edge colors under different natural illuminations.

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    Nieves, Juan Luis; Nascimento, Sérgio M C; Romero, Javier

    2012-02-01

    Essential to sensory processing in the human visual system is natural illumination, which can vary considerably not only across space but also along the day depending on the atmospheric conditions and the sun's position in the sky. In this work, edges derived from the three postreceptoral Luminance, Red-Green, and Blue-Yellow signals were computed from hyperspectral images of natural scenes rendered with daylights of Correlated Color Temperatures (CCTs) from 2735 to 25,889 K; for low CCT, the same analysis was performed using Planckian illuminants up to 800 K. It was found that average luminance and chromatic edge contrasts were maximal for low correlated color temperatures and almost constants above 10,000 K. The magnitude of these contrast changes was, however, only about 2% across the tested daylights. Results suggest that the postreceptoral opponent and nonopponent color vision mechanisms produce almost constant responses for color edge detection under natural illumination.

  9. The evolution of concepts of color vision.

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    Lee, Barry B

    2008-07-01

    The evolution of ideas about the way we see color was closely linked to physical theories of light. Proponents of both corpuscular and wave theories viewed light as a continuous spectrum. This was not easily reconciled with the fact that, for the human eye, all colors can be matched by mixture of three primaries. Physicists such as Mayer who described trichromatic color matching often assumed that there were just three types of rays in the spectrum. This argument was finally resolved by Thomas Young, who noted that trichromatic color matching was consistent with a continuous spectrum if there were just three receptors in the eye. This kind of conceptual mistake, in this case the confusion of the properties of the visual system with physical properties of light, has been common in the history of color science. As another example, the idea of trichromacy was disputed by those who viewed color sensations as opponent processes, red-green, blue-yellow and black-white. The discovery of color-opponent neurons in the visual pathway has partly resolved this dilemma. Much of the physiological substrate of the way we detect and distinguish colors is now established, but the link between the signals leaving the retina and the way we name and order colors is still poorly defined.

  10. Projections of color coding retinal neurons in urodele amphibians.

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    Himstedt, W; Helas, A; Sommer, T J

    1981-01-01

    Optic fiber projection in the brain of Salamandra salamandra was investigated by degeneration techniques. Terminal fields are described in the thalamus and in the optic tectum. Microelectrode recordings were performed from ganglion cells in the retina and from their terminals in the thalamus and tectum in Salamandra and Triturus alpestris. 'On' cells showed maximal sensitivity either in the blue or in the yellow spectral region; they project to the thalamus. Color coding 'on-off' cells project to the tectum opticum. In Triturus a seasonal change in these neurons occurs. Probably due to transition of vitamin A2 into vitamin A1 the spectral sensitivity is different. In springtime blue-red opponent-color neurons were recorded, in fall however, blue-yellow neurons were found.

  11. Perception of color emotions for single colors in red-green defective observers.

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    Sato, Keiko; Inoue, Takaaki

    2016-01-01

    It is estimated that inherited red-green color deficiency, which involves both the protan and deutan deficiency types, is common in men. For red-green defective observers, some reddish colors appear desaturated and brownish, unlike those seen by normal observers. Despite its prevalence, few studies have investigated the effects that red-green color deficiency has on the psychological properties of colors (color emotions). The current study investigated the influence of red-green color deficiency on the following six color emotions: cleanliness, freshness, hardness, preference, warmth, and weight. Specifically, this study aimed to: (1) reveal differences between normal and red-green defective observers in rating patterns of six color emotions; (2) examine differences in color emotions related to the three cardinal channels in human color vision; and (3) explore relationships between color emotions and color naming behavior. Thirteen men and 10 women with normal vision and 13 men who were red-green defective performed both a color naming task and an emotion rating task with 32 colors from the Berkeley Color Project (BCP). Results revealed noticeable differences in the cleanliness and hardness ratings between the normal vision observers, particularly in women, and red-green defective observers, which appeared mainly for colors in the orange to cyan range, and in the preference and warmth ratings for colors with cyan and purple hues. Similarly, naming errors also mainly occurred in the cyan colors. A regression analysis that included the three cone-contrasts (i.e., red-green, blue-yellow, and luminance) as predictors significantly accounted for variability in color emotion ratings for the red-green defective observers as much as the normal individuals. Expressly, for warmth ratings, the weight of the red-green opponent channel was significantly lower in color defective observers than in normal participants. In addition, the analyses for individual warmth ratings in

  12. Perception of color emotions for single colors in red-green defective observers

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    Keiko Sato

    2016-12-01

    Full Text Available It is estimated that inherited red-green color deficiency, which involves both the protan and deutan deficiency types, is common in men. For red-green defective observers, some reddish colors appear desaturated and brownish, unlike those seen by normal observers. Despite its prevalence, few studies have investigated the effects that red-green color deficiency has on the psychological properties of colors (color emotions. The current study investigated the influence of red-green color deficiency on the following six color emotions: cleanliness, freshness, hardness, preference, warmth, and weight. Specifically, this study aimed to: (1 reveal differences between normal and red-green defective observers in rating patterns of six color emotions; (2 examine differences in color emotions related to the three cardinal channels in human color vision; and (3 explore relationships between color emotions and color naming behavior. Thirteen men and 10 women with normal vision and 13 men who were red-green defective performed both a color naming task and an emotion rating task with 32 colors from the Berkeley Color Project (BCP. Results revealed noticeable differences in the cleanliness and hardness ratings between the normal vision observers, particularly in women, and red-green defective observers, which appeared mainly for colors in the orange to cyan range, and in the preference and warmth ratings for colors with cyan and purple hues. Similarly, naming errors also mainly occurred in the cyan colors. A regression analysis that included the three cone-contrasts (i.e., red-green, blue-yellow, and luminance as predictors significantly accounted for variability in color emotion ratings for the red-green defective observers as much as the normal individuals. Expressly, for warmth ratings, the weight of the red-green opponent channel was significantly lower in color defective observers than in normal participants. In addition, the analyses for individual warmth

  13. "Tilt" in color space: Hue changes induced by chromatic surrounds.

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    Klauke, Susanne; Wachtler, Thomas

    2015-01-01

    The perceived color of a chromatic stimulus is influenced by the chromaticity of its surround. To investigate these influences along the dimension of hue, we measured hue changes induced in stimuli of different hues by isoluminant chromatic surrounds. Generally, induced hue changes were directed in color space away from the hue of the inducing surround and depended on the magnitude on the hue difference between stimulus and surround. With increasing difference in hue between stimulus and surround, induced hue changes increased up to a maximum and then decreased for larger differences. This qualitative pattern was similar for different inducers, but quantitatively, induction was weaker along some directions in cone-opponent color space than along other directions. The strongest induction effects were found along an oblique, blue-yellow axis that corresponds to the daylight axis. The overall pattern of the induction effect shows similarities to the well-known tilt effect, where shifts in perceived angle of oriented stimuli are induced by oriented surrounds. This suggests analogous neural representations and similar mechanisms of contextual processing for different visual features such as orientation and color.

  14. Color naming deficits and attention-deficit/hyperactivity disorder: A retinal dopaminergic hypothesis

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    Tannock Rosemary

    2006-01-01

    Full Text Available Abstract Background Individuals with Attention-Deficit/Hyperactive Disorder (ADHD have unexplained difficulties on tasks requiring speeded processing of colored stimuli. Color vision mechanisms, particularly short-wavelength (blue-yellow pathways, are highly sensitive to various diseases, toxins and drugs that alter dopaminergic neurotransmission. Thus, slow color processing might reflect subtle impairments in the perceptual encoding stage of stimulus color, which arise from hypodopaminergic functioning. Presentation of hypotheses 1 Color perception of blue-yellow (but not red-green stimuli is impaired in ADHD as a result of deficient retinal dopamine; 2 Impairments in the blue-yellow color mechanism in ADHD contribute to poor performance on speeded color naming tasks that include a substantial proportion of blue-yellow stimuli; and 3 Methylphenidate increases central dopamine and is also believed to increase retinal dopamine, thereby normalizing blue-yellow color perception, which in turn improves performance on the speeded color naming tasks. Testing the hypothesis Requires three approaches, including:1 direct assessment of color perception in individuals with ADHD to determine whether blue-yellow color perception is selectively impaired; 2 determination of relationship between performance on neuropsychological tasks requiring speeded color processing and color perception; and 3 randomized, controlled pharmacological intervention with stimulant medication to examine the effects of enhancing central dopamine on color perception and task performance Implications of hypothesis If substantiated, the findings of color perception problems would necessitate a re-consideration of current neuropsychological models of attention-deficit/hyperactivity disorder, guide psycho-education, academic instruction, and require consideration of stimulus color in many of the widely used neuropsychological tests.

  15. Color averaging linked to contours, textures and orientation

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    Anstis, S.; Vergeer, M.L.T.; Lier, R.J. van

    2008-01-01

    A blurry, multicolored plaid was made by superimposing two crossed colored sinusoidal gratings: a horizontal red/green grating, and a vertical blue/yellow grating. [Disregarding 'monocular rivalry', which may just be an artifact from eye movements], we have found ways to enhance the visibility of e

  16. Color vision: retinal blues.

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    Johnston, Jamie; Esposti, Federico; Lagnado, Leon

    2012-08-21

    Two complementary studies have resolved the circuitry underlying green-blue color discrimination in the retina. A blue-sensitive interneuron provides the inhibitory signal required for computing green-blue color opponency.

  17. Acquired Color Vision Defects and Hexane Exposure: A Study of San Francisco Bay Area Automotive Mechanics.

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    Beckman, Stella; Eisen, Ellen A; Bates, Michael N; Liu, Sa; Haegerstrom-Portnoy, Gunilla; Hammond, S Katharine

    2016-06-01

    Occupational exposure to solvents, including n-hexane, has been associated with acquired color vision defects. Blue-yellow defects are most common and may be due to neurotoxicity or retinal damage. Acetone may potentiate the neurotoxicity of n-hexane. We present results on nonhexane solvent and hexane exposure and color vision from a cross-sectional study of 835 automotive repair workers in the San Francisco Bay Area, California (2007-2013). Cumulative exposure was estimated from self-reported work history, and color vision was assessed using the Lanthony desaturated D-15 panel test. Log-binomial regression was used to estimate prevalence ratios for color vision defects. Acquired color vision defects were present in 29% of participants, of which 70% were blue-yellow. Elevated prevalence ratios were found for nonhexane solvent exposure, with a maximum of 1.31 (95% confidence interval (CI): 0.86, 2.00) for blue-yellow. Among participants aged ≤50 years, the prevalence ratio for blue-yellow defects was 2.17 (95% CI: 1.03, 4.56) in the highest quartile of nonhexane solvent exposure and 1.62 (95% CI: 0.97, 2.72) in the highest category of exposure to hexane with acetone coexposure. Cumulative exposures to hexane and nonhexane solvents in the highest exposure categories were associated with elevated prevalence ratios for color vision defects in younger participants.

  18. Study on Birefringent Color Generation for a Reflective Ferroelectric Liquid Crystal Display

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    Valyukh, Sergiy; Valyukh, Iryna; Xu, Peizhi; Chigrinov, Vladimir

    2006-10-01

    We study the possibility of a layer of a surface stabilized ferroelectric liquid crystal coupled with several retardation plates for birefringent color generation. Double and single polarizer reflective bistable dichromatic ferroelectric liquid crystal displays are considered. We demonstrate that one or two retardation plates are sufficient for a display having good color characteristics and high brightness. Optimal parameters for green/red and blue/yellow ferroelectric liquid crystal displays are found.

  19. Crayfish recognize the faces of fight opponents.

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    Joanne Van der Velden

    Full Text Available The capacity to associate stimuli underlies many cognitive abilities, including recognition, in humans and other animals. Vertebrates process different categories of information separately and then reassemble the distilled information for unique identification, storage and recall. Invertebrates have fewer neural networks and fewer neural processing options so study of their behavior may reveal underlying mechanisms still not fully understood for any animal. Some invertebrates form complex social colonies and are capable of visual memory-bees and wasps, for example. This ability would not be predicted in species that interact in random pairs without strong social cohesion; for example, crayfish. They have chemical memory but the extent to which they remember visual features is unknown. Here we demonstrate that the crayfish Cherax destructor is capable of visual recognition of individuals. The simplicity of their interactions allowed us to examine the behavior and some characteristics of the visual features involved. We showed that facial features are learned during face-to-face fights, that highly variable cues are used, that the type of variability is important, and that the learning is context-dependent. We also tested whether it is possible to engineer false identifications and for animals to distinguish between twin opponents.

  20. Theoretical aspects of color vision

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    Wolbarsht, M. L.

    1972-01-01

    The three color receptors of Young-Helmholtz and the opponent colors type of information processing postulated by Hering are both present in the human visual system. This mixture accounts for both the phenomena of color matching or hue discrimination and such perceptual qualities of color as the division of the spectrum into color bands. The functioning of the cells in the visual system, especially within the retina, and the relation of this function to color perception are discussed.

  1. Motion opponency and transparency in the human middle temporal area.

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    Garcia, Javier O; Grossman, Emily D

    2009-09-01

    Motion transparency is the perception of multiple, moving surfaces within the same retinal location (for example, a ripple on the surface of a drifting stream), and is an interesting challenge to motion models because multiple velocities must be represented within the same region of space. When these motion vectors are in opposite directions, brief in duration and spatially constrained within a very local region, the result is little or no perceived motion (motion opponency). Both motion transparency and motion opponency inhibit the firing rate of single middle temporal area (MT) neurons as compared with the preferred direction alone, but neither generally influences the firing rate of primary visual cortex neurons. Surprisingly, neuroimaging studies of human middle temporal area (hMT+) have found less activation due only to motion opponency and an increase in neural responses for motion transparency. Here we parametrically manipulate the local balance between competing motion vectors and find an interaction between motion opponency and transparency in the population blood oxygen level-dependent (BOLD) response. We find reduced BOLD amplitude for motion opponency throughout visual cortex, but weakened responses due to perceptual transparency that is most apparent only within the hMT+. We interpret our results as evidence for two distinct mechanisms mediating opponency and transparency.

  2. Memory of opponents is more potent than visual sign stimuli after social hierarchy has been established

    DEFF Research Database (Denmark)

    Korzan, W.J.; Höglund, Erik; Watt, M.J.;

    2007-01-01

    was designed to examine the effect of eyespot manipulation on behavior and social rank during a second interaction between opponents that had previously established a natural dyadic social hierarchy. Prior to a second interaction, eyespots of familiar size-matched combatants were manipulated to reverse...... when animals were re-introduced, regardless of visual signal reversal or length of separation between interactions. However in males with "normal" eyespot color, dominant males had reduced serotonergic activity in CA3 and raphe, while subordinate males exhibited elevated CA3 dopaminergic activity...

  3. Progress in color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2012-01-01

    We present an overview of our recent progress and the current state-of-the-art techniques of color image fusion for night vision applications. Inspired by previously developed color opponent fusing schemes, we initially developed a simple pixel-based false color-mapping scheme that yielded fused fal

  4. A pseudoisochromatic test of color vision for human infants.

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    Mercer, Michele E; Drodge, Suzanne C; Courage, Mary L; Adams, Russell J

    2014-07-01

    Despite the development of experimental methods capable of measuring early human color vision, we still lack a procedure comparable to those used to diagnose the well-identified congenital and acquired color vision anomalies in older children, adults, and clinical patients. In this study, we modified a pseudoisochromatic test to make it more suitable for young infants. Using a forced choice preferential looking procedure, 216 3-to-23-mo-old babies were tested with pseudoisochromatic targets that fell on either a red/green or a blue/yellow dichromatic confusion axis. For comparison, 220 color-normal adults and 22 color-deficient adults were also tested. Results showed that all babies and adults passed the blue/yellow target but many of the younger infants failed the red/green target, likely due to the interaction of the lingering immaturities within the visual system and the small CIE vector distance within the red/green plate. However, older (17-23 mo) infants, color- normal adults and color-defective adults all performed according to expectation. Interestingly, performance on the red/green plate was better among female infants, well exceeding the expected rate of genetic dimorphism between genders. Overall, with some further modification, the test serves as a promising tool for the detection of early color vision anomalies in early human life.

  5. Pain relief as an opponent process: a psychophysical investigation.

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    Leknes, Siri; Brooks, Jonathan C W; Wiech, Katja; Tracey, Irene

    2008-08-01

    Relief from pain in humans is frequently measured by computing the reduction on an 11-point pain intensity scale. However, this definition of relief may be insufficient to capture the utility of pain relief for the individual. Based on pain literature and evidence from studies examining relief and reward, it is clear that pain relief is a broad concept comprising several factors, only one of which is pain intensity reduction. According to opponent process theory, all sensations consist of a primary process and a slow 'opponent process' of opposite valence, the purpose of which is to reduce the deviation from homeostatic balance. Here, opponent process theory provided a framework to explore the interaction between pain, relief and reward. We devised three psychophysical studies examining the temporal (Experiment I) and magnitude (Experiments I and II) relationships between pain severity and its subsequent relief. In Experiment III, we further manipulated the magnitude and pleasantness of relief experienced by applying innocuous cooling following noxious heat stimulation of capsaicin-sensitized skin. Results confirmed predictions from opponent process theory and showed that pain intensity reduction was significantly stronger than relief intensity ratings. Furthermore, continuous relief ratings appeared to reflect the speed of pain intensity reduction. Varying pain intensity parametrically confirmed that relief increases with pain intensity. That innocuous cooling following primary hyperalgesia intervention significantly increased the intensity, pleasantness and duration of relief provides further evidence that pain relief encapsulates more than a reduction in pain intensity. Importantly, the high relief pleasantness ratings confirmed the hypothesized link between relief and reward.

  6. Iterated Prisoner's Dilemma contains strategies that dominate any evolutionary opponent.

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    Press, William H; Dyson, Freeman J

    2012-06-26

    The two-player Iterated Prisoner's Dilemma game is a model for both sentient and evolutionary behaviors, especially including the emergence of cooperation. It is generally assumed that there exists no simple ultimatum strategy whereby one player can enforce a unilateral claim to an unfair share of rewards. Here, we show that such strategies unexpectedly do exist. In particular, a player X who is witting of these strategies can (i) deterministically set her opponent Y's score, independently of his strategy or response, or (ii) enforce an extortionate linear relation between her and his scores. Against such a player, an evolutionary player's best response is to accede to the extortion. Only a player with a theory of mind about his opponent can do better, in which case Iterated Prisoner's Dilemma is an Ultimatum Game.

  7. Opponent process properties of self-administered cocaine.

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    Ettenberg, Aaron

    2004-01-01

    Over the past decade, data collected in our laboratory have demonstrated that self-administered cocaine produces Opponent-Process-like behavioral effects. Animals running a straight alley once each day for IV cocaine develop over trials an approach-avoidance conflict about re-entering the goal box. This conflict behavior is characterized by a stop in forward locomotion (usually at the very mouth of the goal box) followed by a turn and 'retreat' back toward the goal box. The results of a series of studies conducted over the past decade collectively suggest that the behavioral ambivalence exemplified by rats running the alley for IV cocaine stems from concurrent and opponent positive (rewarding) and negative (anxiogenic) properties of the drug--both of which are associated with the goal box. These opponent properties of cocaine have been shown to result from temporally distinct affective states. Using a conditioned place preference test, we have been able to demonstrate that while the initial immediate effects of IV cocaine are reinforcing, the state present 15 min post-injection is aversive. In our most recent work, the co-administration of IV cocaine with either oral ethanol or IV heroin was found to greatly diminish the development and occurrence of retreat behaviors in the runway. It may therefore be that the high incidence of co-abuse of cocaine with either ethanol or heroin, stems from the users' motivation to alleviate some of the negative side effects of cocaine. It would seem then that the Opponent Process Theory has provided a useful conceptual framework for the study of the behavioral consequences of self-administered cocaine including the notion that both positive and negative reinforcement mechanisms are involved in the development and maintenance of cocaine abuse.

  8. Schopenhauer on vision and the colors.

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    Crone, R A

    1997-01-01

    Arthur Schopenhauer (1788-1860) published his book, On Vision and the Colors in 1816. He started from Aristotle's linear color system and Goethe's three pairs of contrast colors. His work preceded Hering's theory of opponent colors but his path to insight was blocked by his anti-Newtonianism and his neo-Hellenistic attitude toward science. Because of his theory of the subjectivity of colors he was a forerunner of the psycho-physiological variant of neo-Kantianism.

  9. Color vision.

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    Gegenfurtner, Karl R; Kiper, Daniel C

    2003-01-01

    Color vision starts with the absorption of light in the retinal cone photoreceptors, which transduce electromagnetic energy into electrical voltages. These voltages are transformed into action potentials by a complicated network of cells in the retina. The information is sent to the visual cortex via the lateral geniculate nucleus (LGN) in three separate color-opponent channels that have been characterized psychophysically, physiologically, and computationally. The properties of cells in the retina and LGN account for a surprisingly large body of psychophysical literature. This suggests that several fundamental computations involved in color perception occur at early levels of processing. In the cortex, information from the three retino-geniculate channels is combined to enable perception of a large variety of different hues. Furthermore, recent evidence suggests that color analysis and coding cannot be separated from the analysis and coding of other visual attributes such as form and motion. Though there are some brain areas that are more sensitive to color than others, color vision emerges through the combined activity of neurons in many different areas.

  10. Response time to colored stimuli in the full visual field

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    Haines, R. F.; Dawson, L. M.; Galvan, T.; Reid, L. M.

    1975-01-01

    Peripheral visual response time was measured in seven dark adapted subjects to the onset of small (45' arc diam), brief (50 msec), colored (blue, yellow, green, red) and white stimuli imaged at 72 locations within their binocular field of view. The blue, yellow, and green stimuli were matched for brightness at about 2.6 sub log 10 units above their absolute light threshold, and they appeared at an unexpected time and location. These data were obtained to provide response time and no-response data for use in various design disciplines involving instrument panel layout. The results indicated that the retina possesses relatively concentric regions within each of which mean response time can be expected to be of approximately the same duration. These regions are centered near the fovea and extend farther horizontally than vertically. Mean foveal response time was fastest for yellow and slowest for blue. Three and one-half percent of the total 56,410 trials presented resulted in no-responses. Regardless of stimulus color, the lowest percentage of no-responses occurred within 30 deg arc from the fovea and the highest within 40 deg to 80 deg arc below the fovea.

  11. Color Evoked Potentials in Adults and Infants.

    Science.gov (United States)

    White, Carroll T.; And Others

    This paper discusses recent studies of the adult visual evoked potential (VEP) which have indicated that specific components of the complex waveform obtained are related to the three basic color processes, and that these components interact in ways that seem to agree with opponent-colors phenomena. The components identified as being related to the…

  12. Gender-related asymmetric brain vasomotor response to color stimulation: a functional transcranial Doppler spectroscopy study

    Directory of Open Access Journals (Sweden)

    Njemanze Philip C

    2010-11-01

    Full Text Available Abstract Background and Purpose The present study was designed to examine the effects of color stimulation on cerebral blood mean flow velocity (MFV in men and women. Methods The study included 16 (8 men and 8 women right-handed healthy subjects. The MFV was recorded simultaneously in both right and left middle cerebral arteries in Dark and white Light conditions, and during color (Blue, Yellow and Red stimulations, and was analyzed using functional transcranial Doppler spectroscopy (fTCDS technique. Results Color processing occurred within cortico-subcortical circuits. In men, wavelength-differencing of Yellow/Blue pairs occurred within the right hemisphere by processes of cortical long-term depression (CLTD and subcortical long-term potentiation (SLTP. Conversely, in women, frequency-differencing of Blue/Yellow pairs occurred within the left hemisphere by processes of cortical long-term potentiation (CLTP and subcortical long-term depression (SLTD. In both genders, there was luminance effect in the left hemisphere, while in men it was along an axis opposite (orthogonal to that of chromatic effect, in women, it was parallel. Conclusion Gender-related differences in color processing demonstrated a right hemisphere cognitive style for wavelength-differencing in men, and a left hemisphere cognitive style for frequency-differencing in women. There are potential applications of fTCDS technique, for stroke rehabilitation and monitoring of drug effects.

  13. Reduced Discrimination in the Tritanopic Confusion Line for Congenital Color Deficiency Adults

    Directory of Open Access Journals (Sweden)

    Marcelo Fernandes Costa

    2016-03-01

    Full Text Available In congenital color blindness the red-green discrimination is impaired resulting in an increased confusion between those colors with yellow. Our post-receptoral physiological mechanisms are organized in two pathways for color perception, a red-green (protanopic and deuteranopic and a blue-yellow (tritanopic. We argue that the discrimination losses in the yellow area in congenital color vision deficiency subjects could generate a subtle loss of discriminability in the tritanopic channel considering discrepancies with yellow perception. We measured color discrimination thresholds for blue and yellow of tritanopic channel in congenital color deficiency subjects. Chromaticity thresholds were measured around a white background (0.1977 u’, 0.4689 v’ in the CIE 1976 consisting of a blue-white and white-yellow thresholds in a tritanopic color confusion line of 21 congenital colorblindness subjects (mean age = 27.7; SD= 5.6 years; 14 deuteranomalous and 7 protanomalous and of 82 (mean age = 25.1; SD= 3.7 years normal color vision subjects. Significant increase in the whole tritanopic axis was found for both deuteranomalous and protanomalous subjects compared to controls for the blue-white (F2,100= 18.80; p< 0.0001 and white-yellow (F2,100= 22.10; p< 0.0001 thresholds. A Principal Component Analysis found a weighting toward to the yellow thresholds induced by deuteranomalous subjects. In conclusion, the discrimination in the tritanopic color confusion axis is significantly reduced in congenital color vision deficiency compared to normal subjects. Since yellow discrimination was impaired the balance of the blue-yellow channels is impaired justifying the increased thresholds found for blue-white discrimination. The weighting toward the yellow region of the color space with the deuteranomalous contributing to that perceptual distortion is discussed in terms of physiological mechanisms.

  14. Blue-yellow photoluminescence from Ce{sup 3+} {yields} Dy{sup 3+} energy transfer in HfO{sub 2}:Ce{sup 3+}:Dy{sup 3+} films deposited by ultrasonic spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Martinez, R. [Instituto de Fisica y Matematicas, Universidad Tecnologica de la Mixteca, Carretera a Acatlima Km. 2.5, Huajuapan de Leon, Oaxaca 69000 (Mexico); Lira, A.C. [Unidad Academica Profesional Nezahualcoyotl, Universidad Autonoma del Estado de Mexico, Av. Bordo de Xochiaca s/n, Nezahualcoyotl, Estado de Mexico 57000 (Mexico); Speghini, A. [DiSTeMeV, Universita di Verona, and INSTM, UdR Verona, Via Della Pieve 70, I-37029 San Floriano (Verona) (Italy); Falcony, C. [Departamento de Fisica, Universidad Autonoma Metropolitana-Iztapalapa, P.O. Box 55-534, Mexico, D.F. 09340 (Mexico); Caldino, U., E-mail: cald@xanum.uam.mx [Departamento de Fisica, Universidad Autonoma Metropolitana-Iztapalapa, P.O. Box 55-534, Mexico, D.F. 09340 (Mexico)

    2011-02-10

    Research highlights: > A blue-yellow emission phosphor excited with UV radiation can be manufactured with CeCl{sub 3} and DyCl{sub 3} doped HfO{sub 2} films deposited at 300 deg. C by the ultrasonic spray pyrolysis technique. > The addition of DyCl{sub 3} in the HfO{sub 2}:CeCl{sub 3} film leads to a non-radiative energy transfer from Ce{sup 3+} to Dy{sup 3+} under Ce{sup 3+} excitation at 280 nm. > The efficiency of this transfer increases up to 86 {+-} 3% for the film with the highest Dy{sup 3+} content. > The possibility of achieving the coordinates of ideal white light with increasing the concentration of dysprosium is demonstrated. - Abstract: HfO{sub 2} films codoped with Ce{sup 3+} and several concentrations of Dy{sup 3+} have been processed by the ultrasonic spray pyrolysis technique. Emissions from Dy{sup 3+} ions centred at 480 and 575 nm associated with the {sup 4}F{sub 9/2} {yields} {sup 6}H{sub 15/2} and {sup 4}F{sub 9/2} {yields} {sup 6}H{sub 13/2} transitions, respectively, have been observed upon UV excitation via a non-radiative energy transfer from Ce{sup 3+} to Dy{sup 3+} ions. Such energy transfer via an electric dipole-quadrupole interaction appears to be the most probable transfer mechanism. The efficiency of this transfer increases up to 86 {+-} 3% for the film with the highest Dy{sup 3+} content (1.9 {+-} 0.1 at.% as measured from EDS). The possibility of achieving the coordinates of ideal white light with increasing the concentration of dysprosium is demonstrated.

  15. Illustrating Color Evolution and Color Blindness by the Decoding Model of Color Vision

    CERN Document Server

    Lu, Chenguang

    2011-01-01

    A symmetrical model of color vision, the decoding model as a new version of zone model, was introduced. The model adopts new continuous-valued logic and works in a way very similar to the way a 3-8 decoder in a numerical circuit works. By the decoding model, Young and Helmholtz's tri-pigment theory and Hering's opponent theory are unified more naturally; opponent process, color evolution, and color blindness are illustrated more concisely. According to the decoding model, we can obtain a transform from RGB system to HSV system, which is formally identical to the popular transform for computer graphics provided by Smith (1978). Advantages, problems, and physiological tests of the decoding model are also discussed.

  16. Color-detection thresholds in rhesus macaque monkeys and humans

    OpenAIRE

    Gagin, Galina; Bohon, Kaitlin S.; Butensky, Adam; Gates, Monica A.; Hu, Jiun-Yiing; Lafer-Sousa, Rosa; Pulumo, Reitumetse L.; Qu, Jane; Stoughton, Cleo M.; Swanbeck, Sonja N.; Conway, Bevil R.

    2014-01-01

    Macaque monkeys are a model of human color vision. To facilitate linking physiology in monkeys with psychophysics in humans, we directly compared color-detection thresholds in humans and rhesus monkeys. Colors were defined by an equiluminant plane of cone-opponent color space. All subjects were tested on an identical apparatus with a four-alternative forced-choice task. Targets were 2° square, centered 2° from fixation, embedded in luminance noise. Across all subjects, the change in detection...

  17. THE IMPORTANCE OF COLOR IN THE MAJOR ROMANIAN BRANDS MARKETING

    Directory of Open Access Journals (Sweden)

    Radiana Maria TAMBA BEREHOIU

    2013-01-01

    Full Text Available The approach of our study is to identify the most important elements which characterize the use of color in the successful Romanian brands marketing, starting from the main media of the marketing messages, such as: website, advertising posters used in campaigns in the past three years and package of the main product. In the background of Romanian brands’ sites, the predominant color is white, followed at a great distance by various shades of green, blue and red. The best positions in the top 50 are associated to the websites that use blue background in construction, followed by the red and yellow. The most common background colors for posters were blue, white, red and green, and the color associated with the best positions in the top 50 for the studied brands was red. The most colors used for the background of the main product package were white, green, blue, yellow and red. The color red was associated with the best top positions. For alcoholic beverages brands, the most common color was yellow, which is mainly used in the design of the main product package (beer and wine brands.

  18. The effect of opponent type on human performance in a three-alternative choice task.

    Science.gov (United States)

    Lie, Celia; Baxter, Jennifer; Alsop, Brent

    2013-10-01

    Adult participants played computerised games of "Paper Scissors Rock". Participants in one group were told that they were playing against the computer, and those in the other group were told that they were playing against another participant in the adjacent room. The participant who won the most games would receive a $50 prize. For both groups however, the opponent's responses (paper, scissors, or rock) were generated by the computer, and the distribution of these responses was varied across four blocks of 126 trials. Results were analysed using the generalised matching law for the three possible pairs of alternatives (paper vs. scissors, paper vs. rock, and scissors vs. rock) across all participants in each group. Overall, significantly higher estimates of sensitivity to the distribution of opponent's responses were obtained from participants who were told their opponent was a computer compared to participants who were told their opponent was another participant. While adding to the existing literature showing that the generalised matching law is an adequate descriptor of human three-alternative choice behaviour, these findings show that external factors such as perceived opponent type can affect the efficacy of reinforcer contingencies on human behaviour. This suggests that generalising the results from tasks performed against a computer to real-life human-to-human interactions warrants some caution.

  19. PREVALENCE OF COLOR BLINDNESS IN STUDENTS: ISFAHAN – 1999

    Directory of Open Access Journals (Sweden)

    A ZANDI

    2001-06-01

    Full Text Available Introduction. The light waves stimulates the retinal cell and eventually the brain cortex will interpret it to a color vision. Color vision defects can be congenital or acquired. Congenital types have a lifelong constant state (Severity. These patients almost always have red-green defect. These types are sex-linked, and according to the existing data have a prevalence of 8 percent in males and 0.5 percent in females. Acquired color vision defects are frequently of blue-yellow type and have an equal prevalence in males and females. Methods. This is a descriptive study and includes 1500 male and 1500 female students of 34 Isfahan high schools, in 1378. We used the "lshihara test" for the evaluation of color vision in these cases. Results. Prevalence of color blindness was 4.2 percent in males and 0.33 percent in female cases. Discussion. These findings are very different from what are registered in our references; so we recommend to perform the "Ishihara test" (which has a low cost and job consultation for all males before entering their occupational field. This can help them to have a better selection, more suitable job and less problems because of their probable color vision defects.

  20. Receiving post-conflict affiliation from the enemy's friend reconciles former opponents.

    Directory of Open Access Journals (Sweden)

    Roman M Wittig

    Full Text Available The adaptive function of bystander initiated post-conflict affiliation (also: consolation & appeasement has been debated for 30 years. Three influential hypotheses compete for the most likely explanation but have not previously been tested with a single data set. The consolation hypothesis argues that bystander affiliation calms the victim and reduces their stress levels. The self-protection hypothesis proposes that a bystander offers affiliation to either opponent to protect himself from redirected aggression by this individual. The relationship-repair hypothesis suggests a bystander can substitute for a friend to reconcile the friend with the friend's former opponent. Here, we contrast all three hypotheses and tested their predictions with data on wild chimpanzees (Pan troglodytes verus of the Taï National Park, Côte d'Ivoire. We examined the first and second post-conflict interactions with respect to both the dyadic and triadic relationships between the bystander and the two opponents. Results showed that female bystanders offered affiliation to their aggressor friends and the victims of their friends, while male bystanders offered affiliation to their victim friends and the aggressors of their friends. For both sexes, bystander affiliation resulted in a subsequent interaction pattern that is expected for direct reconciliation. Bystander affiliation offered to the opponent's friend was more likely to lead to affiliation among opponents in their subsequent interaction. Also, tolerance levels among former opponents were reset to normal levels. In conclusion, this study provides strong evidence for the relationship-repair hypothesis, moderate evidence for the consolation hypothesis and no evidence for the self-protection hypothesis. Furthermore, that bystanders can repair a relationship on behalf of their friend indicates that recipient chimpanzees are aware of the relationships between others, even when they are not kin. This presents a

  1. Evidence for opponent process analysis of sound source location in humans.

    Science.gov (United States)

    Briley, Paul M; Kitterick, Pádraig T; Summerfield, A Quentin

    2013-02-01

    Research with barn owls suggested that sound source location is represented topographically in the brain by an array of neurons each tuned to a narrow range of locations. However, research with small-headed mammals has offered an alternative view in which location is represented by the balance of activity in two opponent channels broadly tuned to the left and right auditory space. Both channels may be present in each auditory cortex, although the channel representing contralateral space may be dominant. Recent studies have suggested that opponent channel coding of space may also apply in humans, although these studies have used a restricted set of spatial cues or probed a restricted set of spatial locations, and there have been contradictory reports as to the relative dominance of the ipsilateral and contralateral channels in each cortex. The current study used electroencephalography (EEG) in conjunction with sound field stimulus presentation to address these issues and to inform the development of an explicit computational model of human sound source localization. Neural responses were compatible with the opponent channel account of sound source localization and with contralateral channel dominance in the left, but not the right, auditory cortex. A computational opponent channel model reproduced every important aspect of the EEG data and allowed inferences about the width of tuning in the spatial channels. Moreover, the model predicted the oft-reported decrease in spatial acuity measured psychophysically with increasing reference azimuth. Predictions of spatial acuity closely matched those measured psychophysically by previous authors.

  2. The voice of the other : A dialogico-rhetorical understanding of opponent and of Toulmin's rebuttal

    NARCIS (Netherlands)

    Slob, Wouter H.; Hitchcock, D; Verheij, B

    2006-01-01

    Although contemporary dialectical logic recognizes an important role for the opponent in argumentation, it remains loyal to the idea that arguments are supportive. In this paper, it is argued that because of this dialectical logic does not take seriously its own dialogical perspective. Without ackno

  3. Video Game Violence and the Female Game Player: Self- and Opponent Gender Effects on Presence and Aggressive Thoughts

    Science.gov (United States)

    Eastin, Matthew S.

    2006-01-01

    Adding depth and breadth to the general aggression model, this paper presents three experiments that test the relationships among user and opponent gender representation, opponent type, presence, and aggressive thoughts from violent video game play. Studies 1 and 2 suggest that females experience greater presence and more aggressive thoughts from…

  4. Uniform color spaces and natural image statistics.

    Science.gov (United States)

    McDermott, Kyle C; Webster, Michael A

    2012-02-01

    Many aspects of visual coding have been successfully predicted by starting from the statistics of natural scenes and then asking how the stimulus could be efficiently represented. We started from the representation of color characterized by uniform color spaces, and then asked what type of color environment they implied. These spaces are designed to represent equal perceptual differences in color discrimination or appearance by equal distances in the space. The relative sensitivity to different axes within the space might therefore reflect the gamut of colors in natural scenes. To examine this, we projected perceptually uniform distributions within the Munsell, CIE L(*)u(*)v(*) or CIE L(*)a(*)b(*) spaces into cone-opponent space. All were elongated along a bluish-yellowish axis reflecting covarying signals along the L-M and S-(L+M) cardinal axes, a pattern typical (though not identical) to many natural environments. In turn, color distributions from environments were more uniform when projected into the CIE L(*)a(*)b(*) perceptual space than when represented in a normalized cone-opponent space. These analyses suggest the bluish-yellowish bias in environmental colors might be an important factor shaping chromatic sensitivity, and also suggest that perceptually uniform color metrics could be derived from natural scene statistics and potentially tailored to specific environments.

  5. Testosterone response to competition in males is unrelated to opponent familiarity or threat appraisal

    OpenAIRE

    2014-01-01

    It has been proposed in the literature that the testosterone (T) response to competition in humans may be modulated by cognitive variables. In a previous experiment with a female sample we have reported that opponent familiarity and threat appraisal moderated the T response to competition in women. With this experiment we aim to investigate if these variables have the same impact on males T response to competition, extending the previous findings in our lab. Forty male participants (20 dyads)...

  6. Flexibility of theory of mind in a matrix game when the opponent's level changes.

    Science.gov (United States)

    Li, Jing; Liu, Xi-Ping; Tang, Wei-Hai

    2014-01-01

    This study used a matrix game to explore adolescents' and young adults' flexibility of theory of mind (ToM) and to examine whether prediction could promote a person's ToM reasoning when the opponent's level of ToM changed during the course of the game. A total of 202 participants of different ages (13, 16, 19, and 24 years) were presented with the task. Results showed that the ToM flexibility in prediction and decision making was not significantly different across the age groups. A person's flexibility of ToM was better when the opponent's level was stable than when the level changed. It was even more difficult for a person to adapt when the opponent changed from a higher-order to lower-order level. The results showed prediction to be a kind of information clue that would prompt people to think further. It is both feasible and discriminative to explore even higher levels of ToM with matrix games.

  7. Eigenvectors of optimal color spectra.

    Science.gov (United States)

    Flinkman, Mika; Laamanen, Hannu; Tuomela, Jukka; Vahimaa, Pasi; Hauta-Kasari, Markku

    2013-09-01

    Principal component analysis (PCA) and weighted PCA were applied to spectra of optimal colors belonging to the outer surface of the object-color solid or to so-called MacAdam limits. The correlation matrix formed from this data is a circulant matrix whose biggest eigenvalue is simple and the corresponding eigenvector is constant. All other eigenvalues are double, and the eigenvectors can be expressed with trigonometric functions. Found trigonometric functions can be used as a general basis to reconstruct all possible smooth reflectance spectra. When the spectral data are weighted with an appropriate weight function, the essential part of the color information is compressed to the first three components and the shapes of the first three eigenvectors correspond to one achromatic response function and to two chromatic response functions, the latter corresponding approximately to Munsell opponent-hue directions 9YR-9B and 2BG-2R.

  8. Color-induced graph colorings

    CERN Document Server

    Zhang, Ping

    2015-01-01

    A comprehensive treatment of color-induced graph colorings is presented in this book, emphasizing vertex colorings induced by edge colorings. The coloring concepts described in this book depend not only on the property required of the initial edge coloring and the kind of objects serving as colors, but also on the property demanded of the vertex coloring produced. For each edge coloring introduced, background for the concept is provided, followed by a presentation of results and open questions dealing with this topic. While the edge colorings discussed can be either proper or unrestricted, the resulting vertex colorings are either proper colorings or rainbow colorings. This gives rise to a discussion of irregular colorings, strong colorings, modular colorings, edge-graceful colorings, twin edge colorings and binomial colorings. Since many of the concepts described in this book are relatively recent, the audience for this book is primarily mathematicians interested in learning some new areas of graph colorings...

  9. Testosterone response to competition in males is unrelated to opponent familiarity or threat appraisal

    Directory of Open Access Journals (Sweden)

    Rui F Oliveira

    2014-11-01

    Full Text Available It has been proposed in the literature that the Testosterone (T response to competition in humans may be modulated by cognitive variables.In a previous experiment with a female sample we have reported that opponent familiarity and threat appraisal moderated the Testosterone (T response to competition in women. With this experiment we aim to investigate if these variables have the same impact on males T response to competition, extending the previous findings in our lab. Forty male participants (twenty dyads were recruited to engage in a same sex, face to face competition using the Number Tracking Test as a competitive task. Levels of T, Cortisol (C and Dehydroepiandrosterone (DHEA were measured before and twenty minutes after the competition. Results show that losers report higher levels of threat than winners and increased their T levels after the competition, however this T change was not predicted by opponent familiarity or threat appraisal. No variation was detected for C and DHEA levels. These findings suggest that there could be sex differences for the moderators/mediators of the T response to competition in humans.

  10. Testosterone response to competition in males is unrelated to opponent familiarity or threat appraisal.

    Science.gov (United States)

    Oliveira, Gonçalo A; Uceda, Sara; Oliveira, Tânia F; Fernandes, Alexandre C; Garcia-Marques, Teresa; Oliveira, Rui F

    2014-01-01

    It has been proposed in the literature that the testosterone (T) response to competition in humans may be modulated by cognitive variables. In a previous experiment with a female sample we have reported that opponent familiarity and threat appraisal moderated the T response to competition in women. With this experiment we aim to investigate if these variables have the same impact on males T response to competition, extending the previous findings in our lab. Forty male participants (20 dyads) were recruited to engage in a same sex, face to face competition using the Number Tracking Test as a competitive task. Levels of T, cortisol (C) and dehydroepiandrosterone (DHEA) were measured before and 20 min after the competition. Results show that losers report higher levels of threat than winners and increased their T levels after the competition, however this T change was not predicted by opponent familiarity or threat appraisal. No variation was detected for C and DHEA levels. These findings suggest that there could be sex differences for the moderators/mediators of the T response to competition in humans.

  11. Characteristics of grouping colors for figure segregation on a multicolored background.

    Science.gov (United States)

    Nagai, Takehiro; Uchikawa, Keiji

    2008-11-01

    A figure is segregated from its background when the colored elements belonging to the figure are grouped together. We investigated the range of color distribution conditions in which a figure could be segregated from its background using the color distribution differences. The stimulus was a multicolored texture composed of randomly shaped pieces. It was divided into two regions: a test region and a background region. The pieces in these two regions had different color distributions in the OSA Uniform Color Space. In our experiments, the subject segregated the figure of the test region using two different procedures. Since the Euclidean distance in the OSA Uniform Color Space corresponds to perceived color difference, if segregation thresholds are determined by only color difference, the thresholds should be independent of position and direction in the color space. In the results, however, the thresholds did depend on position and direction in the OSA Uniform Color Space. This suggests that color difference is not the only factor in figure segregation by color. Moreover, the threshold dependence on position and direction is influenced by the distances in the cone-opponent space whose axes are normalized by discrimination thresholds, suggesting that figure segregation threshold is determined by similar factors in the cone-opponent space for color discrimination. The analysis of the results by categorical color naming suggests that categorical color perception may affect figure segregation only slightly.

  12. Color Blindness

    Science.gov (United States)

    ... rose in full bloom. If you have a color vision defect, you may see these colors differently than most people. There are three main kinds of color vision defects. Red-green color vision defects are the most ...

  13. Signals for color and achromatic contrast in the goldfish inner retina.

    Science.gov (United States)

    Burkhardt, Dwight A

    2014-11-01

    A moving stimulus paradigm was designed to investigate color contrast encoding in the retina. Recently, this paradigm yielded suggestive evidence for color contrast encoding in zebrafish but the significance and generality remain uncertain since the properties of color coding in the zebrafish inner retina are largely unknown. Here, the question of color contrast is pursued in the goldfish retina where there is much accumulated evidence for retinal mechanisms of color vision and opponent color-coding, in particular. Recordings of a sensitive local field potential of the inner retina, the proximal negative response, were made in the intact, superfused retina in the light-adapted state. Responses to color contrast and achromatic contrast were analyzed by comparing responses to a green moving bar on green versus red backgrounds. The quantitative form of the irradiance/response curves was distinctly different under a range of conditions in 32 retinas, thereby providing robust evidence for red-green color contrast. The color contrast is based on successive contrast, occurs in the absence of overt color opponency, and clearly differs from previous findings in the goldfish retina for simultaneous color contrast mediated by color-opponent neurons. The form of the irradiance/response curves suggests that successive color contrast is particularly important when achromatic contrast is low, as often occurs in natural environments. The present results provide a parallel with the well-known principle of human color vision, first proposed by Kirschmann as the third law of color contrast, and may also have implications for the evolution of vertebrate color vision.

  14. Complete sparing of high-contrast color input to motion perception in cortical color blindness.

    Science.gov (United States)

    Cavanagh, P; Hénaff, M A; Michel, F; Landis, T; Troscianko, T; Intriligator, J

    1998-07-01

    It is widely held that color and motion are processed by separate parallel pathways in the visual system, but this view is difficult to reconcile with the fact that motion can be detected in equiluminant stimuli that are defined by color alone. To examine the relationship between color and motion, we tested three patients who had lost their color vision following cortical damage (central achromatopsia). Despite their profound loss in the subjective experience of color and their inability to detect the motion of faint colors, all three subjects showed surprisingly strong responses to high-contrast, moving color stimuli--equal in all respects to the performance of subjects with normal color vision. The pathway from opponent-color detectors in the retina to the motion analysis areas must therefore be independent of the damaged color centers in the occipitotemporal area. It is probably also independent of the motion analysis area MT/V5, because the contribution of color to motion detection in these patients is much stronger than the color response of monkey area MT.

  15. Distinguishing the opponents in the prisoner dilemma in well-mixed populations

    CERN Document Server

    Wardil, Lucas

    2010-01-01

    Here we study the effects of adopting different strategies against different opponent instead of adopting the same strategy against all of them in the prisoner dilemma structured in well-mixed populations. We consider an evolutionary process in which strategies that provide reproductive success are imitated and players replace one of their worst interactions by the new one. We set individuals in a well-mixed population so that network reciprocity effect is excluded and we analyze both synchronous and asynchronous updates. As a consequence of the replacement rule, we show that mutual cooperation is never destroyed and the initial fraction of mutual cooperation is a lower bound for the level of cooperation. We show by simulation and mean-field analysis that for synchronous update cooperation dominates while for asynchronous update only cooperations associated to the initial mutual cooperations are maintained. As a side effect of the replacement rule, an "implicit punishment" mechanism comes up in a way that exp...

  16. Communication, opponents, and clan performance in online games: a social network approach.

    Science.gov (United States)

    Lee, Hong Joo; Choi, Jaewon; Kim, Jong Woo; Park, Sung Joo; Gloor, Peter

    2013-12-01

    Online gamers form clans voluntarily to play together and to discuss their real and virtual lives. Although these clans have diverse goals, they seek to increase their rank in the game community by winning more battles. Communications among clan members and battles with other clans may influence the performance of a clan. In this study, we compared the effects of communication structure inside a clan, and battle networks among clans, with the performance of the clans. We collected battle histories, posts, and comments on clan pages from a Korean online game, and measured social network indices for communication and battle networks. Communication structures in terms of density and group degree centralization index had no significant association with clan performance. However, the centrality of clans in the battle network was positively related to the performance of the clan. If a clan had many battle opponents, the performance of the clan improved.

  17. Friends shrink foes: the presence of comrades decreases the envisioned physical formidability of an opponent.

    Science.gov (United States)

    Fessler, Daniel M T; Holbrook, Colin

    2013-05-01

    In situations of potential violent conflict, deciding whether to fight, flee, or try to negotiate entails assessing many attributes contributing to the relative formidability of oneself and one's opponent. Summary representations can usefully facilitate such assessments of multiple factors. Because physical size and strength are both phylogenetically ancient and ontogenetically recurrent contributors to the outcome of violent conflicts, these attributes provide plausible conceptual dimensions that may be used by the mind to summarize the relative formidability of opposing parties. Because the presence of allies is a vital factor in determining victory, we hypothesized that men accompanied by male companions would therefore envision a solitary foe as physically smaller and less muscular than would men who were alone. We document the predicted effect in two studies, one using naturally occurring variation in the presence of male companions and one employing experimental manipulation of this factor.

  18. Color vision deficiency in a middle-aged population: the Shahroud Eye Study.

    Science.gov (United States)

    Jafarzadehpur, Ebrahim; Hashemi, Hassan; Emamian, Mohammad Hassan; Khabazkhoob, Mehdi; Mehravaran, Shiva; Shariati, Mohammad; Fotouhi, Akbar

    2014-10-01

    The aim of this study was to determine the prevalence of color vision defects in the middle-age population of Shahroud, Iran. We selected 6,311 people from the 40- to 64-year-old population through random cluster sampling. Color vision testing was performed with the Farnsworth D-15. Cases with similar and symmetric results in both eyes were classified as hereditary, and those with asymmetric results were considered acquired. Cases that did not conform to standard patterns were classified as unknown category. Of 5,190 respondents (response rate 82.2 %), 5,102 participants underwent the color vision test. Of these, 14.7 % (95 % confidence interval 13.7-15.6) had some type of color vision deficiency. Of the 2,157 male participants, 6.2 % were hereditary and 10.2 % were acquired and of the 2,945 female participants, 3.1 % were hereditary and 10 % were acquired. Hereditary color deficiencies were mostly of the deutan form (63.8 %), and acquired deficiencies were mostly tritan (66.1 %). The prevalence of hereditary and acquired color vision deficiency, as well as different types of red-green and blue-yellow color vision defects significantly increased with age (p color vision defects among the middle-aged population of Shahroud was significantly different from that seen in the younger population. This could be due to changes associated with age, gender, medical and ocular conditions, and differences in race and environment. Thus, results of previous examinations and the overall health status should be considered before making any judgment about the status of color vision in middle-aged people.

  19. Reinforcement Learning in the Game of Othello: Learning Against a Fixed Opponent and Learning from Self-Play

    NARCIS (Netherlands)

    van der Ree, Michiel; Wiering, Marco

    2013-01-01

    This paper compares three strategies in using reinforcement learning algorithms to let an artificial agent learnto play the game of Othello. The three strategies that are compared are: Learning by self-play, learning from playing against a fixed opponent, and learning from playing against a fixed op

  20. Automated processes in tennis: do left-handed players benefit from the tactical preferences of their opponents?

    Science.gov (United States)

    Loffing, Florian; Hagemann, Norbert; Strauss, Bernd

    2010-02-01

    Previous research on laterality in sport suggests an over-representation of left-handers in interactive sports such as tennis and cricket. These findings potentially reflect left-handers' advantage over their right-handed competitors in those sports. Although considered crucial for successful performance, the tactical component of their superiority has yet to be analysed. Two studies were conducted to test for a side bias in tennis players' tactical preferences. In the first study, 108 right- and left-handed players of varying skill watched rallies on a computer screen and had to indicate where they would place the ball in the opposing half. The results showed the tactical preference of players to place more balls on a left-handed opponent's mostly stronger forehand side compared with when faced with a right-hander. In the second study, 54 professional tennis matches involving right- and left-handers were analysed with respect to ball placement frequencies on the opponent's backhand side. Significantly fewer balls were hit to the backhand side of a left-handed opponent, thus replicating the findings of Study 1 in on-court situations. Both studies indicate players' preference to place shots to their right irrespective of their opponent's handedness. Findings support the assumption that left-handers might enjoy a strategic advantage in tennis.

  1. Skilled players' and novices' difficulty anticipating left- vs. right-handed opponents' action intentions varies across different points in time.

    Science.gov (United States)

    Loffing, Florian; Hagemann, Norbert; Schorer, Jörg; Baker, Joseph

    2015-04-01

    A left-handers' performance advantage in interactive sports is assumed to result from their relative rarity compared to right-handers. Part of this advantage may be explained by athletes facing difficulties anticipating left-handers' action intentions, particularly when anticipation is based on kinematic cues available at an early stage of an opponent's movement. Here we tested whether the type of volleyball attack is predicted better against right- vs. left-handed opponents' movements and whether such handedness effects are evident at earlier time points in skilled players than novices. In a video-based experiment volleyball players and novices predicted the type of shot (i.e., smash vs. lob) of left- and right-handed volleyball attacks occluded at six different time points. Overall, right-handed attacks were better anticipated than left-handed attacks, volleyball players outperformed novices, and performance improved in later occlusion conditions. Moreover, in skilled players the handedness effect was most pronounced when attacks were occluded 480 ms prior to hand-ball-contact, whereas in novices it was most evident 240 ms prior to hand-ball-contact. Our findings provide further evidence of the effect of an opponent's handedness on action outcome anticipation and suggest that its occurrence in the course of an opponent's unfolding action likely depends on an observers' domain-specific skill.

  2. A different form of color vision in mantis shrimp.

    Science.gov (United States)

    Thoen, Hanne H; How, Martin J; Chiou, Tsyr-Huei; Marshall, Justin

    2014-01-24

    One of the most complex eyes in the animal kingdom can be found in species of stomatopod crustaceans (mantis shrimp), some of which have 12 different photoreceptor types, each sampling a narrow set of wavelengths ranging from deep ultraviolet to far red (300 to 720 nanometers). Functionally, this chromatic complexity has presented a mystery. Why use 12 color channels when three or four are sufficient for fine color discrimination? Behavioral wavelength discrimination tests (Δλ functions) in stomatopods revealed a surprisingly poor performance, ruling out color vision that makes use of the conventional color-opponent coding system. Instead, our experiments suggest that stomatopods use a previously unknown color vision system based on temporal signaling combined with scanning eye movements, enabling a type of color recognition rather than discrimination.

  3. Opponent and bidirectional control of movement velocity in the basal ganglia.

    Science.gov (United States)

    Yttri, Eric A; Dudman, Joshua T

    2016-05-02

    For goal-directed behaviour it is critical that we can both select the appropriate action and learn to modify the underlying movements (for example, the pitch of a note or velocity of a reach) to improve outcomes. The basal ganglia are a critical nexus where circuits necessary for the production of behaviour, such as the neocortex and thalamus, are integrated with reward signalling to reinforce successful, purposive actions. The dorsal striatum, a major input structure of basal ganglia, is composed of two opponent pathways, direct and indirect, thought to select actions that elicit positive outcomes and suppress actions that do not, respectively. Activity-dependent plasticity modulated by reward is thought to be sufficient for selecting actions in the striatum. Although perturbations of basal ganglia function produce profound changes in movement, it remains unknown whether activity-dependent plasticity is sufficient to produce learned changes in movement kinematics, such as velocity. Here we use cell-type-specific stimulation in mice delivered in closed loop during movement to demonstrate that activity in either the direct or indirect pathway is sufficient to produce specific and sustained increases or decreases in velocity, without affecting action selection or motivation. These behavioural changes were a form of learning that accumulated over trials, persisted after the cessation of stimulation, and were abolished in the presence of dopamine antagonists. Our results reveal that the direct and indirect pathways can each bidirectionally control movement velocity, demonstrating unprecedented specificity and flexibility in the control of volition by the basal ganglia.

  4. Dopaminergic signaling mediates the motivational response underlying the opponent process to chronic but not acute nicotine.

    Science.gov (United States)

    Grieder, Taryn E; Sellings, Laurie H; Vargas-Perez, Hector; Ting-A-Kee, Ryan; Siu, Eric C; Tyndale, Rachel F; van der Kooy, Derek

    2010-03-01

    The mesolimbic dopamine (DA) system is implicated in the processing of the positive reinforcing effect of all drugs of abuse, including nicotine. It has been suggested that the dopaminergic system is also involved in the aversive motivational response to drug withdrawal, particularly for opiates, however, the role for dopaminergic signaling in the processing of the negative motivational properties of nicotine withdrawal is largely unknown. We hypothesized that signaling at dopaminergic receptors mediates chronic nicotine withdrawal aversions and that dopaminergic signaling would differentially mediate acute vs dependent nicotine motivation. We report that nicotine-dependent rats and mice showed conditioned place aversions to an environment paired with abstinence from chronic nicotine that were blocked by the DA receptor antagonist alpha-flupenthixol (alpha-flu) and in DA D(2) receptor knockout mice. Conversely, alpha-flu pretreatment had no effect on preferences for an environment paired with abstinence from acute nicotine. Taken together, these results suggest that dopaminergic signaling is necessary for the opponent motivational response to nicotine in dependent, but not non-dependent, rodents. Further, signaling at the DA D(2) receptor is critical in mediating withdrawal aversions in nicotine-dependent animals. We suggest that the alleviation of nicotine withdrawal primarily may be driving nicotine motivation in dependent animals.

  5. Color Blindness

    Institute of Scientific and Technical Information of China (English)

    严双红

    2007-01-01

    About one in 12 boys is color-blind, and one in every 400 girls, so in each school class there are likely to be at least one or two people who are color-blind. Because they are color- blind from birth, most people do not know that they are color-

  6. Color blindness

    Science.gov (United States)

    ... color blindness often have problems seeing reds and greens, too. The most severe form of color blindness is achromatopsia. This is a rare condition in which a person cannot see any color, only shades of gray. Most color blindness is due to ...

  7. Roughness perception in tactile channels: evidence for an opponent process in the sense of touch.

    Science.gov (United States)

    Gescheider, George A; Wright, John H

    2013-09-01

    Magnitude estimates of the tactile roughness of raised-dot surfaces revealed that perceived overall roughness, defined as the combination of the perceived roughness of the dot pattern and the perceived roughness of the individual dots in the pattern, is an inverted U-shaped function of dot spacing, reaching a maximum at approximately 3.0 mm of dot separation. The hypothesis that Pacinian corpuscles are involved in roughness perception has been supported by the finding that selective adaptation of the Pacinian corpuscle (PC) channel with a 250-Hz stimulus at 20-dB SL results in a decrease in the perceived overall roughness of the raised-dot surface at the fingertip. The effect of PC channel adaptation on perceived overall roughness was attributable entirely to a reduction in the perceived roughness of the individual raised dots; PC adaptation had no effect on the perceived roughness of the raised-dot pattern. Selective adaptation of the slowly adapting type I (SA I) channel with a 5-Hz stimulus at 20-dB SL had the opposite effect of PC channel adaptation and resulted in an increase in the perceived roughness of the individual raised dots, and consequently the perceived overall roughness of the raised-dot surface. As was the case with PC channel adaptation, SA I channel adaptation had no effect on the perceived roughness of the pattern. Adaptation with a compound adapting stimulus containing 5- and 250-Hz components at 20-dB SL had no effect on perceived overall roughness, which suggests that the PC and SA I channels operate antagonistically in an opponent-process fashion in the perception of the microstructure of a textured surface. Neither PC adaptation nor SA I adaptation affected perceived pattern roughness, which suggests that pattern roughness is coded by relative rather than by absolute spatial variation in firing rate.

  8. Ocean Color

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellite-derived Ocean Color Data sets from historical and currently operational NASA and International Satellite missions including the NASA Coastal Zone Color...

  9. Entropy, color, and color rendering.

    Science.gov (United States)

    Price, Luke L A

    2012-12-01

    The Shannon entropy [Bell Syst. Tech J.27, 379 (1948)] of spectral distributions is applied to the problem of color rendering. With this novel approach, calculations for visual white entropy, spectral entropy, and color rendering are proposed, indices that are unreliant on the subjectivity inherent in reference spectra and color samples. The indices are tested against real lamp spectra, showing a simple and robust system for color rendering assessment. The discussion considers potential roles for white entropy in several areas of color theory and psychophysics and nonextensive entropy generalizations of the entropy indices in mathematical color spaces.

  10. Bio-inspired color image enhancement model

    Science.gov (United States)

    Zheng, Yufeng

    2009-05-01

    Human being can perceive natural scenes very well under various illumination conditions. Partial reasons are due to the contrast enhancement of center/surround networks and opponent analysis on the human retina. In this paper, we propose an image enhancement model to simulate the color processes in the human retina. Specifically, there are two center/surround layers, bipolar/horizontal and ganglion/amacrine; and four color opponents, red (R), green (G), blue (B), and yellow (Y). The central cell (bipolar or ganglion) takes the surrounding information from one or several horizontal or amacrine cells; and bipolar and ganglion both have ON and OFF sub-types. For example, a +R/-G bipolar (red-center- ON/green-surround-OFF) will be excited if only the center is illuminated, or inhibited if only the surroundings (bipolars) are illuminated, or stay neutral if both center and surroundings are illuminated. Likewise, other two color opponents with ON-center/OFF-surround, +G/-R and +B/-Y, follow the same rules. The yellow (Y) channel can be obtained by averaging red and green channels. On the other hand, OFF-center/ON-surround bipolars (i.e., -R/+G and -G/+R, but no - B/+Y) are inhibited when the center is illuminated. An ON-bipolar (or OFF-bipolar) only transfers signals to an ONganglion (or OFF-ganglion), where amacrines provide surrounding information. Ganglion cells have strong spatiotemporal responses to moving objects. In our proposed enhancement model, the surrounding information is obtained using weighted average of neighborhood; excited or inhibited can be implemented with pixel intensity increase or decrease according to a linear or nonlinear response; and center/surround excitations are decided by comparing their intensities. A difference of Gaussian (DOG) model is used to simulate the ganglion differential response. Experimental results using natural scenery pictures proved that, the proposed image enhancement model by simulating the two-layer center

  11. Color invariance

    NARCIS (Netherlands)

    Geusebroek, J.M.; van den Boomgaard, R.; Smeulders, A.W.M.; Geerts, H.

    2001-01-01

    This paper presents the measurement of colored object reflectance, under different, general assumptions regarding the imaging conditions. We exploit the Gaussian scale-space paradigm for color images to define a framework for the robust measurement of object reflectance from color images. Object ref

  12. Color Algebras

    Science.gov (United States)

    Mulligan, Jeffrey B.

    2017-01-01

    A color algebra refers to a system for computing sums and products of colors, analogous to additive and subtractive color mixtures. We would like it to match the well-defined algebra of spectral functions describing lights and surface reflectances, but an exact correspondence is impossible after the spectra have been projected to a three-dimensional color space, because of metamerism physically different spectra can produce the same color sensation. Metameric spectra are interchangeable for the purposes of addition, but not multiplication, so any color algebra is necessarily an approximation to physical reality. Nevertheless, because the majority of naturally-occurring spectra are well-behaved (e.g., continuous and slowly-varying), color algebras can be formulated that are largely accurate and agree well with human intuition. Here we explore the family of algebras that result from associating each color with a member of a three-dimensional manifold of spectra. This association can be used to construct a color product, defined as the color of the spectrum of the wavelength-wise product of the spectra associated with the two input colors. The choice of the spectral manifold determines the behavior of the resulting system, and certain special subspaces allow computational efficiencies. The resulting systems can be used to improve computer graphic rendering techniques, and to model various perceptual phenomena such as color constancy.

  13. Color Categories and Color Appearance

    Science.gov (United States)

    Webster, Michael A.; Kay, Paul

    2012-01-01

    We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary…

  14. The detection of various color combinations under different chromatic ambient illuminations.

    Science.gov (United States)

    Neri, D F; Luria, S M; Kobus, D A

    1986-06-01

    Our purpose was to reveal the effects of ambient illumination color and various foreground/background color pairings on a choice reaction time task performed on a color CRT. Six men and two women with normal color vision served as observers in a four-alternative forced choice procedure. A small (18' visual angle) colored circle appeared in the center of one of the unmarked quadrants of the screen. The observer's task was to respond as quickly as possible to this target by pressing one of four buttons corresponding to its location. We found that target colors that were opponent to the background colors were most quickly detected. Detection was enhanced by maximizing both brightness and chromatic contrast, but brightness contrast was much more effective. Chromatic ambient lighting which was a log unit dimmer than the target luminance had no effect on performance.

  15. Color Analysis

    Science.gov (United States)

    Wrolstad, Ronald E.; Smith, Daniel E.

    Color, flavor, and texture are the three principal quality attributes that determine food acceptance, and color has a far greater influence on our judgment than most of us appreciate. We use color to determine if a banana is at our preferred ripeness level, and a discolored meat product can warn us that the product may be spoiled. The marketing departments of our food corporations know that, for their customers, the color must be "right." The University of California Davis scorecard for wine quality designates four points out of 20, or 20% of the total score, for color and appearance (1). Food scientists who establish quality control specifications for their product are very aware of the importance of color and appearance. While subjective visual assessment and use of visual color standards are still used in the food industry, instrumental color measurements are extensively employed. Objective measurement of color is desirable for both research and industrial applications, and the ruggedness, stability, and ease of use of today's color measurement instruments have resulted in their widespread adoption.

  16. Processing of Color Words Activates Color Representations

    Science.gov (United States)

    Richter, Tobias; Zwaan, Rolf A.

    2009-01-01

    Two experiments were conducted to investigate whether color representations are routinely activated when color words are processed. Congruency effects of colors and color words were observed in both directions. Lexical decisions on color words were faster when preceding colors matched the color named by the word. Color-discrimination responses…

  17. Ready for a fight? The physiological effects of detecting an opponent's pheromone cues prior to a contest.

    Science.gov (United States)

    Garcia, Mark J; Williams, John; Sinderman, Benjamin; Earley, Ryan L

    2015-10-01

    Reception of pheromone cues can elicit significant physiological (e.g. steroid hormone levels) changes in the recipient. These pheromone-induced physiological changes have been well documented for male-female interactions, but scarcely in same-sex interactions (male-male and female-female). We sought to address this dearth in the current literature and examine whether mangrove rivulus fish (Kryptolebias marmoratus) could detect and, ultimately, mount a physiological response to the pheromone signature of a potential, same-sex competitor. We examined steroid hormone levels in mangrove rivulus exposed to one of three treatments: 1) isolation, 2) exposure to pheromones of a size-matched partner, and 3) pheromone exposure to a size-matched opponent followed by a physical encounter with the opponent. We found that exposure to a competitor's pheromone cues elicited a significant increase in testosterone levels. Increases in testosterone were similar across genetically distinct lineages derived from geographically distinct populations. Further, testosterone levels were similar between individuals only exposed to pheromone cues and individuals exposed to both pheromone cues and a subsequent physical encounter. Our findings led us to generate a number of testable predictions regarding how mangrove rivulus utilize pheromone signals in social interactions, the molecular mechanisms linking social stimuli and hormonal responses, and the possible adaptive benefits of hormonal responsiveness to receiving a potential competitor's pheromone cues.

  18. COLOR IMAGES

    Directory of Open Access Journals (Sweden)

    Dominique Lafon

    2011-05-01

    Full Text Available The goal of this article is to present specific capabilities and limitations of the use of color digital images in a characterization process. The whole process is investigated, from the acquisition of digital color images to the analysis of the information relevant to various applications in the field of material characterization. A digital color image can be considered as a matrix of pixels with values expressed in a vector-space (commonly 3 dimensional space whose specificity, compared to grey-scale images, is to ensure a coding and a representation of the output image (visualisation printing that fits the human visual reality. In a characterization process, it is interesting to regard color image attnbutes as a set of visual aspect measurements on a material surface. Color measurement systems (spectrocolorimeters, colorimeters and radiometers and cameras use the same type of light detectors: most of them use Charge Coupled Devices sensors. The difference between the two types of color data acquisition systems is that color measurement systems provide a global information of the observed surface (average aspect of the surface: the color texture is not taken into account. Thus, it seems interesting to use imaging systems as measuring instruments for the quantitative characterization of the color texture.

  19. Color matrix display simulation based upon luminance and chromatic contrast sensitivity of early vision

    Science.gov (United States)

    Martin, Russel A.; Ahumada, Albert J., Jr.; Larimer, James O.

    1992-01-01

    This paper describes the design and operation of a new simulation model for color matrix display development. It models the physical structure, the signal processing, and the visual perception of static displays, to allow optimization of display design parameters through image quality measures. The model is simple, implemented in the Mathematica computer language, and highly modular. Signal processing modules operate on the original image. The hardware modules describe backlights and filters, the pixel shape, and the tiling of the pixels over the display. Small regions of the displayed image can be visualized on a CRT. Visual perception modules assume static foveal images. The image is converted into cone catches and then into luminance, red-green, and blue-yellow images. A Haar transform pyramid separates the three images into spatial frequency and direction-specific channels. The channels are scaled by weights taken from human contrast sensitivity measurements of chromatic and luminance mechanisms at similar frequencies and orientations. Each channel provides a detectability measure. These measures allow the comparison of images displayed on prospective devices and, by that, the optimization of display designs.

  20. Opponent actor learning (OpAL): modeling interactive effects of striatal dopamine on reinforcement learning and choice incentive.

    Science.gov (United States)

    Collins, Anne G E; Frank, Michael J

    2014-07-01

    The striatal dopaminergic system has been implicated in reinforcement learning (RL), motor performance, and incentive motivation. Various computational models have been proposed to account for each of these effects individually, but a formal analysis of their interactions is lacking. Here we present a novel algorithmic model expanding the classical actor-critic architecture to include fundamental interactive properties of neural circuit models, incorporating both incentive and learning effects into a single theoretical framework. The standard actor is replaced by a dual opponent actor system representing distinct striatal populations, which come to differentially specialize in discriminating positive and negative action values. Dopamine modulates the degree to which each actor component contributes to both learning and choice discriminations. In contrast to standard frameworks, this model simultaneously captures documented effects of dopamine on both learning and choice incentive-and their interactions-across a variety of studies, including probabilistic RL, effort-based choice, and motor skill learning.

  1. Color contrast and stability as key elements for effectivewarning signals

    Directory of Open Access Journals (Sweden)

    Lina María Arenas

    2014-06-01

    Full Text Available Vivid warning signals (aposematism have evolved repeatedly throughout the animal kingdom. However, relatively few studies consider what makes an effective signal, such as in terms of preventing attack and promoting avoidance learning by predators. Signal form varies substantially among and sometimes within species, but there has also been apparent convergence on relatively few main color types. We aimed to determine why warning signals often combine red, orange, yellow and black colors, and specifically to determine whether these colors provide highly salient and reliable visual signals under a range of environmental conditions. Using digital image analysis, we modeled ladybird (ladybug coloration to an avian visual system. We calculated the contrast of several different ladybird species against an average green background, based on predicted opponent color channel responses in bird vision. Our results suggest that longwave colors (i.e. red, orange are more contrasting than colors such as blue, against green natural backgrounds. Moreover, these colors yield relatively unchanging (stable signals throughout the day and under different weather conditions. These analyses show how aposematic signals have evolved under selection to be more effective by being more conspicuous and reliable to the visual system of their potential avian predators.

  2. Color-detection thresholds in rhesus macaque monkeys and humans.

    Science.gov (United States)

    Gagin, Galina; Bohon, Kaitlin S; Butensky, Adam; Gates, Monica A; Hu, Jiun-Yiing; Lafer-Sousa, Rosa; Pulumo, Reitumetse L; Qu, Jane; Stoughton, Cleo M; Swanbeck, Sonja N; Conway, Bevil R

    2014-07-15

    Macaque monkeys are a model of human color vision. To facilitate linking physiology in monkeys with psychophysics in humans, we directly compared color-detection thresholds in humans and rhesus monkeys. Colors were defined by an equiluminant plane of cone-opponent color space. All subjects were tested on an identical apparatus with a four-alternative forced-choice task. Targets were 2° square, centered 2° from fixation, embedded in luminance noise. Across all subjects, the change in detection thresholds from initial testing to plateau performance (“learning”) was similar for +L − M (red) colors and +M − L (bluish-green) colors. But the extent of learning was higher for +S (lavender) than for −S (yellow-lime); moreover, at plateau performance, the cone contrast at the detection threshold was higher for +S than for −S. These asymmetries may reflect differences in retinal circuitry for S-ON and S-OFF. At plateau performance, the two species also had similar detection thresholds for all colors, although monkeys had shorter reaction times than humans and slightly lower thresholds for colors that modulated L/M cones. We discuss whether these observations, together with previous work showing that monkeys have lower spatial acuity than humans, could be accounted for by selective pressures driving higher chromatic sensitivity at the cost of spatial acuity amongst monkeys, specifically for the more recently evolved L − M mechanism.

  3. Physiological outperformance at the morphologically-transformed edge of the cyanobacteriosponge Terpios hoshinota (Suberitidae: Hadromerida when confronting opponent corals.

    Directory of Open Access Journals (Sweden)

    Jih-Terng Wang

    Full Text Available Terpios hoshinota, an encrusting cyanosponge, is known as a strong substrate competitor of reef-building corals that kills encountered coral by overgrowth. Terpios outbreaks cause significant declines in living coral cover in Indo-Pacific coral reefs, with the damage usually lasting for decades. Recent studies show that there are morphological transformations at a sponge's growth front when confronting corals. Whether these morphological transformations at coral contacts are involved with physiological outperformance (e.g., higher metabolic activity or nutritional status over other portions of Terpios remains equivocal. In this study, we compared the indicators of photosynthetic capability and nitrogen status of a sponge-cyanobacteria association at proximal, middle, and distal portions of opponent corals. Terpios tissues in contact with corals displayed significant increases in photosynthetic oxygen production (ca. 61%, the δ13C value (ca. 4%, free proteinogenic amino acid content (ca. 85%, and Gln/Glu ratio (ca. 115% compared to middle and distal parts of the sponge. In contrast, the maximum quantum yield (Fv/Fm, which is the indicator usually used to represent the integrity of photosystem II, of cyanobacteria photosynthesis was low (0.256~0.319 and showed an inverse trend of higher values in the distal portion of the sponge that might be due to high and variable levels of cyanobacterial phycocyanin. The inconsistent results between photosynthetic oxygen production and Fv/Fm values indicated that maximum quantum yields might not be a suitable indicator to represent the photosynthetic function of the Terpios-cyanobacteria association. Our data conclusively suggest that Terpios hoshinota competes with opponent corals not only by the morphological transformation of the sponge-cyanobacteria association but also by physiological outperformance in accumulating resources for the battle.

  4. Vector model for normal and dichromatic color vision.

    Science.gov (United States)

    Guth, S L; Massof, R W; Benzschawel, T

    1980-02-01

    The inclusion of cone mechanisms in a slightly revised version of an earlier model allows accounts of phenomena that involve receptor effects as well as dichromatic color vision. Intensity-dependent parameters that stimulate the adaptation of receptors and opponent and nonopponent mechanisms are varied to predict a wide range of data for both normals and dichromats, including: (i) color matching; (ii) the approximate apparent hue and saturation of the spectrum; (iii) foveal spectral sensitivities obtained by flicker photometry and by detection in the dark and under conditions of achromatic or chromatic adaptation; (iv) heterochromatic additivity failures in the dark-adapted and chromatically adapted eye; (v) approximate differences between brightness and luminance; and, (vi) color and wavelength discrimination under varying adaptation conditions.

  5. Color tejido

    OpenAIRE

    Rius Tormo, Palmira

    2010-01-01

    Póster presentado en el IX Congreso Nacional del Color, Alicante, 29-30 junio, 1-2 julio 2010. La exposición que se propone tiene como núcleo principal el color y muestra las posibilidades expresivas que aporta a los diferentes materiales. Las 7 obras presentadas buscan la armonía estética y la fuerza simbólica.

  6. A Vision Chip for Color Segmentation and Pattern Matching

    Directory of Open Access Journals (Sweden)

    Ralph Etienne-Cummings

    2003-06-01

    Full Text Available A 128(H × 64(V × RGB CMOS imager is integrated with region-of-interest selection, RGB-to-HSI transformation, HSI-based pixel segmentation, (36bins × 12bits-HSI histogramming, and sum-of-absolute-difference (SAD template matching. Thirty-two learned color templates are stored and compared to each image. The chip captures the R, G, and B images using in-pixel storage before passing the pixel content to a multiplying digital-to-analog converter (DAC for white balancing. The DAC can also be used to pipe in images for a PC. The color processing uses a biologically inspired color opponent representation and an analog lookup table to determine the Hue (H of each pixel. Saturation (S is computed using a loser-take-all circuit. Intensity (I is given by the sum of the color components. A histogram of the segments of the image, constructed by counting the number of pixels falling into 36 Hue intervals of 10 degrees, is stored on a chip and compared against the histograms of new segments using SAD comparisons. We demonstrate color-based image segmentation and object recognition with this chip. Running at 30 fps, it uses 1 mW. To our knowledge, this is the first chip that integrates imaging, color segmentation, and color-based object recognition at the focal plane.

  7. The effects of spatial pattern on color appearance

    Science.gov (United States)

    Hu, Weijie; Zhao, Dazun

    2006-01-01

    The color appearance of an image is different from that of a uniform color patch because of spatial pattern effects. We have studied how the color appearance of square wave bars varies with stimulus strength and spatial frequency. The asymmetric matching method is used in the experiments, which means the color of uniform patch is adjusted by an observer to match the color appearance of the bars in square wave patterns. The square wave patterns have relatively low spatial frequencies of 1, 2, 4 and 8 cycles per degree (c p d). The area of a square wave pattern box only spreads a 2° field to the observers which means the matching is established mainly in the fovea. We find the matches are not colorimetric matches. The experiment data are analyzed and a conclusion that the cone contrast of the uniform patch is nearly proportional to the square wave stimulus strength is obtained, which reveal the property of color- homogeneity. Therefore the matches would have the basic properties of a linear system. In the article, all analyses are based on the opponent-color system. Precision of the experiments and some reasons about the data diversity are also discussed. The final conclusion suggests that the pattern separable mode could be used to predict the matches.

  8. Color superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Wilczek, F. [Institute for Advanced Study, Princeton, NJ (United States)

    1997-09-22

    The asymptotic freedom of QCD suggests that at high density - where one forms a Fermi surface at very high momenta - weak coupling methods apply. These methods suggest that chiral symmetry is restored and that an instability toward color triplet condensation (color superconductivity) sets in. Here I attempt, using variational methods, to estimate these effects more precisely. Highlights include demonstration of a negative pressure in the uniform density chiral broken phase for any non-zero condensation, which we take as evidence for the philosophy of the MIT bag model; and demonstration that the color gap is substantial - several tens of MeV - even at modest densities. Since the superconductivity is in a pseudoscalar channel, parity is spontaneously broken.

  9. Colored Preons

    CERN Document Server

    Finkelstein, Robert J

    2009-01-01

    Previous studies have suggested complementary models of the elementary particles as (a) quantum knots and (b) preonic nuclei that are field and particle descriptions, respectively, of the same particles. This earlier work, carried out in the context of standard electroweak (SU(2) x U(1)) physics, is here extended to the strong interactions by the introduction of color (SU(3)) charges.

  10. Color Sense

    Science.gov (United States)

    Johnson, Heidi S. S.; Maki, Jennifer A.

    2009-01-01

    This article reports a study conducted by members of the WellU Academic Integration Subcommittee of The College of St. Scholastica's College's Healthy Campus Initiative plan whose purpose was to determine whether changing color in the classroom could have a measurable effect on students. One simple improvement a school can make in a classroom is…

  11. Impartial coloring games

    CERN Document Server

    Beaulieu, Gabriel; Duchêne, Eric

    2012-01-01

    Coloring games are combinatorial games where the players alternate painting uncolored vertices of a graph one of $k > 0$ colors. Each different ruleset specifies that game's coloring constraints. This paper investigates six impartial rulesets (five new), derived from previously-studied graph coloring schemes, including proper map coloring, oriented coloring, 2-distance coloring, weak coloring, and sequential coloring. For each, we study the outcome classes for special cases and general computational complexity. In some cases we pay special attention to the Grundy function.

  12. Color calculations for and perceptual assessment of computer graphic images

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, G.W.

    1986-01-01

    Realistic image synthesis involves the modelling of an environment in accordance with the laws of physics and the production of a final simulation that is perceptually acceptable. To be considered a scientific endeavor, synthetic image generation should also include the final step of experimental verification. This thesis concentrates on the color calculations that are inherent in the production of the final simulation and on the perceptual assessment of the computer graphic images that result. The fundamental spectral sensitivity functions that are active in the human visual system are introduced and are used to address color-blindness issues in computer graphics. A digitally controlled color television monitor is employed to successfully implement both the Farnsworth Munsell 100 hues test and a new color vision test that yields more accurate diagnoses. Images that simulate color blind vision are synthesized and are used to evaluate color scales for data display. Gaussian quadrature is used with a set of opponent fundamental to select the wavelengths at which to perform synthetic image generation.

  13. Computational color technology

    CERN Document Server

    Kang, Henry R

    2006-01-01

    Henry Kang provides the fundamental color principles and mathematical tools to prepare the reader for a new era of color reproduction, and for subsequent applications in multispectral imaging, medical imaging, remote sensing, and machine vision. This book is intended to bridge the gap between color science and computational color technology, putting color adaptation, color constancy, color transforms, color display, and color rendition in the domain of vector-matrix representations and theories. Computational Color Technology deals with color digital images on the spectral level using vector-m

  14. Emergence of Exploratory, Technical and Tactical Behavior in Small-Sided Soccer Games when Manipulating the Number of Teammates and Opponents

    Science.gov (United States)

    Ric, Angel; Hristovski, Robert; Torres-Ronda, Lorena; Vicente, Emili; Sampaio, Jaime

    2016-01-01

    The effects that different constraints have on the exploratory behavior, measured by the variety and quantity of different responses within a game situation, is of the utmost importance for successful performance in team sports. The aim of this study was to determine how the number of teammates and opponents affects the exploratory behavior of both professional and amateur players in small-sided soccer games. Twenty-two professional (age 25.6 ± 4.9 years) and 22 amateur (age 23.1 ± 0.7 years) male soccer players played three small-sided game formats (4 vs. 3, 4 vs. 5, and 4 vs. 7). These trials were video-recorded and a systematic observation instrument was used to notate the actions, which were subsequently analyzed by means of a principal component analysis and the dynamic overlap order parameter (measure to identify the rate and breadth of exploratory behavior on different time scales). Results revealed that a higher the number of opponents required for more frequent ball controls. Moreover, with a higher number of teammates, there were more defensive actions focused on protecting the goal, with more players balancing. In relation to attack, an increase in the number of opponents produced a decrease in passing, driving and controlling actions, while an increase in the number of teammates led to more time being spent in attacking situations. A numerical advantage led to less exploratory behavior, an effect that was especially clear when playing within a team of seven players against four opponents. All teams showed strong effects of the number of teammates on the exploratory behavior when comparing 5 vs 7 or 3 vs 7 teammates. These results seem to be independent of the players’ level. PMID:28005978

  15. Exploring Opponent Formats

    DEFF Research Database (Denmark)

    Jensen, Mads Møller; Rasmussen, Majken; Grønbæk, Kaj

    2013-01-01

    The recent growth in development and research in computer-supported physical games has sprouted a wide variety of games merging qualities from both computer games and sports. Despite the increasing interest in this type of games, exploration of their specific game mechanics and the understanding...

  16. The relationship of psychophysiological characteristics karate qualifications in light weight category with the effective implementation of kick leg techniques in upper level of the opponent

    Directory of Open Access Journals (Sweden)

    Vladimir Saienko

    2015-04-01

    Full Text Available Purpose: set the density of the relationship of psycho-physiological characteristics of karate qualifications in light weight category with the efficiency of the implementation of kick leg techniques in the upper level of the opponent. Material and Methods: The study involved thirty highly skilled karatekas in light weight category. Conducted pedagogical and psychophysiological testing, carried out an analysis of competitive actions, carried out a special analysis of scientific and methodical literature, applied the methods of mathematical statistics. Results: The degree of correlation between the obtained numerical results of psycho-physiological characteristics and indicators of the effectiveness different types of gradient kicking karate qualifications in light weight category in upper level of the opponent. Conclusions: karatekas high qualifications in light weight category, the higher the strength of neural processes in the processing of information in the imposed rhythm, the more reliable in a competitive match under implementation methods kick leg them with maximum power and speed-up in upper level of the opponent, and at the higher they characteristic of functional mobility of nervous processes in the processing of information in the imposed rhythm, the greater the likelihood of fighters attacking moves fast.

  17. Color blindness and Rorschach color responsivity.

    Science.gov (United States)

    Corsino, B V

    1985-10-01

    Color vision deficits occur in 10% of the American white male population. Thus, color blindness may invalidate diagnostic hypotheses generated from Rorschach data. The Rorschach protocols of 43 white, college male color-blind subjects were compared to the protocols of normally sighted controls. The color-blind group manifested fewer pure "C" responses. No significant between group differences emerged for any of the other primary Rorschach color variables. Pure "C" responses rarely figure prominently in Rorschach evaluations, and the apparent lowered frequency of these responses by the color-blind is insufficient to warrant modification of current Rorschach practice. The data suggest that color blindness is unlikely to confound Rorschach assessment.

  18. Automated assessment of the quality of diffusion tensor imaging data using color cast of color-encoded fractional anisotropy images.

    Science.gov (United States)

    He, Xiaofu; Liu, Wei; Li, Xuzhou; Li, Qingli; Liu, Feng; Rauh, Virginia A; Yin, Dazhi; Bansal, Ravi; Duan, Yunsuo; Kangarlu, Alayar; Peterson, Bradley S; Xu, Dongrong

    2014-06-01

    Diffusion tensor imaging (DTI) data often suffer from artifacts caused by motion. These artifacts are especially severe in DTI data from infants, and implementing tight quality controls is therefore imperative for DTI studies of infants. Currently, routine procedures for quality assurance of DTI data involve the slice-wise visual inspection of color-encoded, fractional anisotropy (CFA) images. Such procedures often yield inconsistent results across different data sets, across different operators who are examining those data sets, and sometimes even across time when the same operator inspects the same data set on two different occasions. We propose a more consistent, reliable, and effective method to evaluate the quality of CFA images automatically using their color cast, which is calculated on the distribution statistics of the 2D histogram in the color space as defined by the International Commission on Illumination (CIE) on lightness and a and b (LAB) for the color-opponent dimensions (also known as the CIELAB color space) of the images. Experimental results using DTI data acquired from neonates verified that this proposed method is rapid and accurate. The method thus provides a new tool for real-time quality assurance for DTI data.

  19. Preparatory Body State before Reacting to an Opponent: Short-Term Joint Torque Fluctuation in Real-Time Competitive Sports.

    Directory of Open Access Journals (Sweden)

    Keisuke Fujii

    Full Text Available In a competitive sport, the outcome of a game is determined by an athlete's relationship with an unpredictable and uncontrolled opponent. We have previously analyzed the preparatory state of ground reaction forces (GRFs dividing non-weighted and weighted states (i.e., vertical GRFs below and above 120% of body weight, respectively in a competitive ballgame task and demonstrated that the non-weighted state prevented delay of the defensive step and promoted successful guarding. However, the associated kinetics of lower extremity joints during a competitive sports task remains unknown. The present study aims to investigate the kinetic characteristics of a real-time competitive sport before movement initiation. As a first kinetic study on a competitive sport, we initially compared the successful defensive kinetics with a relatively stable preparatory state and the choice-reaction sidestep as a control movement. Then, we investigated the kinetic cause of the outcome in a 1-on-1 dribble in terms of the preparatory states according to our previous study. The results demonstrated that in successful defensive motions in the non-weighted state guarding trial, the times required for the generation of hip abduction and three extension torques for the hip, knee, and ankle joints were significantly shortened compared with the choice-reaction sidestep, and hip abduction and hip extension torques were produced almost simultaneously. The sport-specific movement kinetics emerges only in a more-realistic interactive experimental setting. A comparison of the outcomes in the 1-on-1 dribble and preparatory GRF states showed that, in the non-weighted state, the defenders guarded successfully in 68.0% of the trials, and the defender's initiation time was earlier than that in the weighted state (39.1%. In terms of kinetics, the root mean squares of the derivative of hip abduction and three extension torques in the non-weighted state were smaller than those in the

  20. Embedding Color Watermarks in Color Images

    Directory of Open Access Journals (Sweden)

    Wu Tung-Lin

    2003-01-01

    Full Text Available Robust watermarking with oblivious detection is essential to practical copyright protection of digital images. Effective exploitation of the characteristics of human visual perception to color stimuli helps to develop the watermarking scheme that fills the requirement. In this paper, an oblivious watermarking scheme that embeds color watermarks in color images is proposed. Through color gamut analysis and quantizer design, color watermarks are embedded by modifying quantization indices of color pixels without resulting in perceivable distortion. Only a small amount of information including the specification of color gamut, quantizer stepsize, and color tables is required to extract the watermark. Experimental results show that the proposed watermarking scheme is computationally simple and quite robust in face of various attacks such as cropping, low-pass filtering, white-noise addition, scaling, and JPEG compression with high compression ratios.

  1. Color vision and color formation in dragonflies.

    Science.gov (United States)

    Futahashi, Ryo

    2016-10-01

    Dragonflies including damselflies are colorful and large-eyed insects, which show remarkable sexual dimorphism, color transition, and color polymorphism. Recent comprehensive visual transcriptomics has unveiled an extraordinary diversity of opsin genes within the lineage of dragonflies. These opsin genes are differentially expressed between aquatic larvae and terrestrial adults, as well as between dorsal and ventral regions of adult compound eyes. Recent topics of color formation in dragonflies are also outlined. Non-iridescent blue color is caused by coherent light scattering from the quasiordered nanostructures, whereas iridescent color is produced by multilayer structures. Wrinkles or wax crystals sometimes enhances multilayer structural colors. Sex-specific and stage-specific color differences in red dragonflies is attributed to redox states of ommochrome pigments.

  2. Urine - abnormal color

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003139.htm Urine - abnormal color To use the sharing features on this page, please enable JavaScript. The usual color of urine is straw-yellow. Abnormally colored urine ...

  3. Skin color - patchy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003224.htm Skin color - patchy To use the sharing features on this page, please enable JavaScript. Patchy skin color is areas where the skin color is irregular. ...

  4. Digital color imaging

    CERN Document Server

    Fernandez-Maloigne, Christine; Macaire, Ludovic

    2013-01-01

    This collective work identifies the latest developments in the field of the automatic processing and analysis of digital color images.For researchers and students, it represents a critical state of the art on the scientific issues raised by the various steps constituting the chain of color image processing.It covers a wide range of topics related to computational color imaging, including color filtering and segmentation, color texture characterization, color invariant for object recognition, color and motion analysis, as well as color image and video indexing and retrieval. <

  5. a New Color Correction Method for Underwater Imaging

    Science.gov (United States)

    Bianco, G.; Muzzupappa, M.; Bruno, F.; Garcia, R.; Neumann, L.

    2015-04-01

    Recovering correct or at least realistic colors of underwater scenes is a very challenging issue for imaging techniques, since illumination conditions in a refractive and turbid medium as the sea are seriously altered. The need to correct colors of underwater images or videos is an important task required in all image-based applications like 3D imaging, navigation, documentation, etc. Many imaging enhancement methods have been proposed in literature for these purposes. The advantage of these methods is that they do not require the knowledge of the medium physical parameters while some image adjustments can be performed manually (as histogram stretching) or automatically by algorithms based on some criteria as suggested from computational color constancy methods. One of the most popular criterion is based on gray-world hypothesis, which assumes that the average of the captured image should be gray. An interesting application of this assumption is performed in the Ruderman opponent color space lαβ, used in a previous work for hue correction of images captured under colored light sources, which allows to separate the luminance component of the scene from its chromatic components. In this work, we present the first proposal for color correction of underwater images by using lαβ color space. In particular, the chromatic components are changed moving their distributions around the white point (white balancing) and histogram cutoff and stretching of the luminance component is performed to improve image contrast. The experimental results demonstrate the effectiveness of this method under gray-world assumption and supposing uniform illumination of the scene. Moreover, due to its low computational cost it is suitable for real-time implementation.

  6. Unsupervised color normalisation for H and E stained histopathology image analysis

    Science.gov (United States)

    Celis, Raúl; Romero, Eduardo

    2015-12-01

    In histology, each dye component attempts to specifically characterise different microscopic structures. In the case of the Hematoxylin-Eosin (H&E) stain, universally used for routine examination, quantitative analysis may often require the inspection of different morphological signatures related mainly to nuclei patterns, but also to stroma distribution. Nevertheless, computer systems for automatic diagnosis are often fraught by color variations ranging from the capturing device to the laboratory specific staining protocol and stains. This paper presents a novel colour normalisation method for H&E stained histopathology images. This method is based upon the opponent process theory and blindly estimates the best color basis for the Hematoxylin and Eosin stains without relying on prior knowledge. Stain Normalisation and Color Separation are transversal to any Framework of Histopathology Image Analysis.

  7. Bipolar cell pathways for color and luminance vision in a dichromatic mammalian retina.

    Science.gov (United States)

    Li, Wei; DeVries, Steven H

    2006-05-01

    The mammalian retina is fundamentally dichromatic, with trichromacy only recently emerging in some primates. In dichromats, an array of short wavelength-sensitive (S, blue) and middle wavelength-sensitive (M, green) cones is sampled by approximately ten bipolar cell types, and the sampling pattern determines how retinal ganglion cells and ultimately higher visual centers encode color and luminance. By recording from cone-bipolar cell pairs in the retina of the ground squirrel, we show that the bipolar cell types sample cone signals in three ways: one type receives input exclusively from S-cones, two types receive mixed S/M-cone input and the remaining types receive an almost pure M-cone signal. Bipolar cells that carry S- or M-cone signals can have a role in color discrimination and may contact color-opponent ganglion cells. Bipolar cells that sum signals from S- and M-cones may signal to ganglion cells that encode luminance.

  8. Texture affects color emotion

    NARCIS (Netherlands)

    Lucassen, M.P.; Gevers, T.; Gijsenij, A.

    2011-01-01

    Several studies have recorded color emotions in subjects viewing uniform color (UC) samples. We conduct an experiment to measure and model how these color emotions change when texture is added to the color samples. Using a computer monitor, our subjects arrange samples along four scales: warm-cool,

  9. Industrial Color Physics

    CERN Document Server

    Klein, Georg A

    2010-01-01

    This unique book starts with a short historical overview of the development of the theories of color vision and applications of industrial color physics. The three dominant factors producing color - light source, color sample, and observer - are described in detail. The standardized color spaces are shown and related color values are applied to characteristic color qualities of absorption as well as of effect colorants. The fundamentals of spectrometric and colorimetric measuring techniques together with specific applications are described. Theoretical models for radiative transfer in transparent, translucent, and opaque layers are detailed; the two, three, and multi-flux approximations are presented for the first time in a coherent formalism. These methods constitute the fundamentals not only for the important classical methods, but also modern methods of recipe prediction applicable to all known colorants. The text is supplied with 52 tables, more than 200 partially colored illustrations, an appendix, and a...

  10. Cortical fMRI activation to opponents' body kinematics in sport-related anticipation: expert-novice differences with normal and point-light video.

    Science.gov (United States)

    Wright, M J; Bishop, D T; Jackson, R C; Abernethy, B

    2011-08-18

    Badminton players of varying skill levels viewed normal and point-light video clips of opponents striking the shuttle towards the viewer; their task was to predict in which quadrant of the court the shuttle would land. In a whole-brain fMRI analysis we identified bilateral cortical networks sensitive to the anticipation task relative to control stimuli. This network is more extensive and localised than previously reported. Voxel clusters responding more strongly in experts than novices were associated with all task-sensitive areas, whereas voxels responding more strongly in novices were found outside these areas. Task-sensitive areas for normal and point-light video were very similar, whereas early visual areas responded differentially, indicating the primacy of kinematic information for sport-related anticipation.

  11. Colors Can Affect Us!

    Institute of Scientific and Technical Information of China (English)

    张俊斌

    2006-01-01

    Different colors affect us differently.The following will show us how they work. Experiment proves that math problems worked on yellow paper have fewer mistakes than problems written on other colors of paper.

  12. Color chiral solitons

    CERN Document Server

    Novozhilov, V Yu; Novozhilov, Victor; Novozhilov, Yuri

    2002-01-01

    We discuss specific features of color chiral solitons (asymptotics, possibility of confainment, quantization) at example of isolated SU(2) color skyrmions, i.e. skyrmions in a background field which is the vacuum field forming the gluon condensate.

  13. White polymer light-emitting diodes co-doped with three phosphorescent iridium(III) complexes aimed at improvement of color rendering properties

    Energy Technology Data Exchange (ETDEWEB)

    Ikawa, Shigeru [Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531 (Japan); Yagi, Shigeyuki, E-mail: yagi@chem.osakafu-u.ac.jp [Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531 (Japan); Maeda, Takeshi; Nakazumi, Hiroyuki [Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531 (Japan); Sakurai, Yoshiaki [Textile and Polymer Section, Technology Research Institute of Osaka Prefecture, 2-7-1 Ayumino, Izumi, Osaka 594-1157 (Japan)

    2014-11-15

    To obtain white electroluminescence (EL) with a high color rendering index (CRI), we fabricated polymer light-emitting diodes (PLEDs) co-doped with high-efficiency blue-, yellow- and red-phosphorescent bis-cyclometalated iridium(III) complexes (Ir-1, Ir-2, and Ir-3, respectively) in a single emitting layer based on a PVCz-OXD-7 blended film (PVCz, poly(9-vinylcarbazole); OXD-7, 1,3-bis[5-(4-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene). When the constituent ratio of the emitting layer (PVCz:OXD-7:Ir-1:Ir-2:Ir-3) was adjusted to 10:3.0:1.2:0.060:0.036 in weight ratio, an approximately white PLED (WPLED) was obtained showing a Commission Internationale de l'Eclairage (CIE) chromaticity coordinate of (0.38, 0.44) and a CRI of 83 at 1000 cd m{sup −2}. To elucidate the energy transfer among the phosphorescent emitters, we also investigated the photophysical properties of the PVCz-based thin film whose constituent ratio is the same as the emitting layer of the WPLED, and it was found that a cascade of the energy transfer from the blue to the red via the yellow emitter considerably contributes to the emission process along with the direct energy transfer from the blue to the red and yellow emitters. - Highlights: • PLEDs co-doped with three phosphorescent emitters were fabricated. • Approximately white EL with a color rendering index of 83 was obtained. • The energy transfer mechanism among the phosphorescent emitters was elucidated.

  14. Reimagining the Color Wheel

    Science.gov (United States)

    Snyder, Jennifer

    2011-01-01

    Color wheels are a traditional project for many teachers. The author has used them in art appreciation classes for many years, but one problem she found when her pre-service art education students created colored wheels was that they were boring: simple circles, with pie-shaped pieces, which students either painted or colored in. This article…

  15. Measurement of Color Texture

    NARCIS (Netherlands)

    Hoang, M.A.; Geusebroek, J.M.; Chantler, M.

    2002-01-01

    In computer vision, measurement of image properties such as color or texture is essential. In this paper, we propose a solid framework for the local measurement of texture in color images. We give a physical basis for the integration of the well-known Gabor filters with the measurement of color. Our

  16. Color: Implications in dentistry

    Directory of Open Access Journals (Sweden)

    Sikri Vimal

    2010-01-01

    Full Text Available The success of restorative dentistry is determined on the basis of functional and esthetic results. To achieve esthetics, four basic determinants are required in sequence; viz., position, contour, texture and color. The knowledge of the concept of color is essential for achieving good esthetics. This review compiles the various aspects of color, its measurements and shade matching in dentistry.

  17. Tanslation of Color Words

    Institute of Scientific and Technical Information of China (English)

    徐丹

    2009-01-01

    Being a minor part in the translation field,the translation of color words is far more complex than people may have imagined.Apart from the literal meaning of color words in the target language,there are other factors that affect the understanding.This paper mainly focuses on three main characteristics of color words that make the translation work difficult-color words'variations and combinations,rich symbolic meanings and culture differences.It also provides possible ways to deal with the prickly problem of finding equivalents,the complexity of transferring symbolic meanings and the subtle problem of crossing culture boundaries in translation of color words.

  18. [Colors and their meaning in culture and psychology--a historical outline and contemporary status of color vision theories].

    Science.gov (United States)

    Grzybowski, Andrzej; Lewicka, Romana; Torlińska, Teresa; Stelcer, Bogusław

    2008-01-01

    The mechanism of color perception has intrigued scholars from antiquity. However, the understanding of this phenomena only came with the recognition of the nature of light and visual perception. Ancient concepts, present in science until the Renaissance, were based more on philosophical considerations and theoretical speculations than on anatomical studies and a matter-of-fact assessment of physiological functions of the visual system. From antiquity to 17th century scientific approach to the concept of vision was dominated by two theories: intromission and extramission (emanation). Intromission theory, propagated by Alhazen (lbn al.-Haythama), Vitello, John Peckham, Roger Bacon and Leonardo da Vinci, assumed that the light was transmitted from the observed object perpendicularly to the transparent eye structures. Johannes Kepler was the first scholar to propose that the retina was the receptive part of the eye. In the first half of the 17th century, Kepler's groundbreaking optical achievements and anatomical discoveries of many other scientists cast new light on the understanding of the role of different eye structures, finally wiping out the intromission theory. A further major achievement contributing to the recognition of the true nature of colors was a theory presented by Newton in 1688. He argued that they were colored rays, and not white light, that were composed of homogenous and pure light. It was, however, not until the 19th century when two modern theories of color appeared, i.e. a trichromatic theory mostly associated with the names of Young and Hemlholtz, and an opponent colors theory of Hering. In the 20th century, the two theories--previously assumed as contradictory--were joined into the zone theories of color vision. Colors have their cultural and social meanings, as far as a very individual and personal interpretation. In the former function they are used to illustrate some cultural and sociological phenomena; in the latter, they are helpful in

  19. Acquired color vision deficiency.

    Science.gov (United States)

    Simunovic, Matthew P

    2016-01-01

    Acquired color vision deficiency occurs as the result of ocular, neurologic, or systemic disease. A wide array of conditions may affect color vision, ranging from diseases of the ocular media through to pathology of the visual cortex. Traditionally, acquired color vision deficiency is considered a separate entity from congenital color vision deficiency, although emerging clinical and molecular genetic data would suggest a degree of overlap. We review the pathophysiology of acquired color vision deficiency, the data on its prevalence, theories for the preponderance of acquired S-mechanism (or tritan) deficiency, and discuss tests of color vision. We also briefly review the types of color vision deficiencies encountered in ocular disease, with an emphasis placed on larger or more detailed clinical investigations.

  20. Colors, colored overlays, and reading skills

    Directory of Open Access Journals (Sweden)

    Arcangelo eUccula

    2014-07-01

    Full Text Available In this article, we are concerned with the role of colors in reading written texts. It has been argued that colored overlays applied above written texts positively influence both reading fluency and reading speed. These effects would be particularly evident for those individuals affected by the so called Meares-Irlen syndrome, i.e. who experience eyestrain and/or visual distortions – e.g. color, shape or movement illusions – while reading. This condition would interest the 12-14% of the general population and up to the 46% of the dyslexic population. Thus, colored overlays have been largely employed as a remedy for some aspects of the difficulties in reading experienced by dyslexic individuals, as fluency and speed. Despite the wide use of colored overlays, how they exert their effects has not been made clear yet. Also, according to some researchers, the results supporting the efficacy of colored overlays as a tool for helping readers are at least controversial. Furthermore, the very nature of the Meares-Irlen syndrome has been questioned. Here we provide a concise, critical review of the literature.

  1. Color Reproduction with a Smartphone

    Science.gov (United States)

    Thoms, Lars-Jochen; Colicchia, Giuseppe; Girwidz, Raimund

    2013-01-01

    The world is full of colors. Most of the colors we see around us can be created on common digital displays simply by superposing light with three different wavelengths. However, no mixture of colors can produce a fully pure color identical to a spectral color. Using a smartphone, students can investigate the main features of primary color addition…

  2. The nature of colors

    Science.gov (United States)

    da Pos, Osvaldo

    2002-06-01

    Color is a visible aspect of objects and lights, and as such is an objective characteristic of our phenomenal world. Correspondingly also objects and lights are objective, although their subjectivity cannot be disregarded since they belong to our phenomenal world. The distinction between perception and sensation deals with colors seen either in complex displays or in isolation. Reality of colors is apparently challenged by virtual reality, while virtual reality is a good example of what colors are. It seems difficult to combine that aspect of reality colors have in our experience and the concept that colors represent something in the external environment: the distinction between stimulation and perceived object is crucial for understanding the relationships between phenomenal world and physical reality. A modern concept of isomorphism seems useful in interpreting the role of colors. The relationship between the psychological structure of colors and the physical stimulation is enlightened by the analysis of pseudocolors. The perceptual, subjective characteristics of colors go along with the subjectivity of scientific concepts. Colors, emotions, and concepts are all in some people's mind: none of them is independent of the subject mind. Nevertheless they can be communicated from person to person by an appropriate scientific terminology.

  3. Affective Image Colorization

    Institute of Scientific and Technical Information of China (English)

    Xiao-Hui Wang; Jia Jia; Han-Yu Liao; Lian-Hong Cai

    2012-01-01

    Colorization of gray-scale images has attracted many attentions for a long time.An important role of image color is the conveyer of emotions (through color themes).The colorization with an undesired color theme is less useful,even it is semantically correct.However this has been rarely considered.Automatic colorization respecting both the semantics and the emotions is undoubtedly a challenge.In this paper,we propose a complete system for affective image colorization.We only need the user to assist object segmentation along with text labels and an affective word.First,the text labels along with other object characters are jointly used to filter the internet images to give each object a set of semantically correct reference images.Second,we select a set of color themes according to the affective word based on art theories.With these themes,a generic algorithm is used to select the best reference for each object,balancing various requirements.Finally,we propose a hybrid texture synthesis approach for colorization.To the best of our knowledge,it is the first system which is able to efficiently colorize a gray-scale image semantically by an emotionally controllable fashion.Our experiments show the effectiveness of our system,especially the benefit compared with the previous Markov random field (MRF) based method.

  4. Selection of small color palette for color image quantization

    Science.gov (United States)

    Chau, Wing K.; Wong, S. K. M.; Yang, Xuedong; Wan, Shijie J.

    1992-05-01

    Two issues are involved in color image quantization: color palette selection and color mapping. A common practice for color palette selection is to minimize the color distortion for each pixel (the median-cut, the variance-based and the k-means algorithms). After the color palette has been chosen, a quantized image may be generated by mapping the original color of each pixel onto its nearest color in the color palette. Such an approach can usually produce quantized images of high quality with 128 or more colors. For 32 - 64 colors, the quality of the quantized images is often acceptable with the aid of dithering techniques in the color mapping process. For 8 - 16 color, however, the above statistical method for color selection becomes no longer suitable because of the great reduction of color gamut. In order to preserve the color gamut of the original image, one may want to select the colors in such a way that the convex hull formed by these colors in the RGB color space encloses most colors of the original image. Quantized images generated in such a geometrical way usually preserve a lot of image details, but may contain too much high frequency noises. This paper presents an effective algorithm for the selection of very small color palette by combining the strengths of the above statistical and geometrical approaches. We demonstrate that with the new method images of high quality can be produced by using only 4 to 8 colors.

  5. Laser color recording unit

    Science.gov (United States)

    Jung, E.

    1984-05-01

    A color recording unit was designed for output and control of digitized picture data within computer controlled reproduction and picture processing systems. In order to get a color proof picture of high quality similar to a color print, together with reduced time and material consumption, a photographic color film material was exposed pixelwise by modulated laser beams of three wavelengths for red, green and blue light. Components of different manufacturers for lasers, acousto-optic modulators and polygon mirrors were tested, also different recording methods as (continuous tone mode or screened mode and with a drum or flatbed recording principle). Besides the application for the graphic arts - the proof recorder CPR 403 with continuous tone color recording with a drum scanner - such a color hardcopy peripheral unit with large picture formats and high resolution can be used in medicine, communication, and satellite picture processing.

  6. The road coloring problem

    CERN Document Server

    Trahtman, A N

    2007-01-01

    The synchronizing word of deterministic automaton is a word in the alphabet of colors (considered as letters) of its edges that maps the automaton to a single state. A coloring of edges of a directed graph is synchronizing if the coloring turns the graph into deterministic finite automaton possessing a synchronizing word. The road coloring problem is a problem of synchronizing coloring of directed finite strongly connected graph with constant outdegree of all its vertices if the greatest common divisor of lengths of all its cycles is one. The problem was posed by Adler, Goodwyn and Weiss over 30 years ago and evoked a noticeable interest among the specialists in theory of graphs, deterministic automata and symbolic dynamics. The problem is described even in "Vikipedia" - the popular Internet Encyclopedia. The positive solution of the road coloring problem is presented.

  7. The Translation Of Colors

    Institute of Scientific and Technical Information of China (English)

    王冰

    2012-01-01

    Different nations have different or even opposite perception of color, which results in non-equivalence of color words in mutual translation between Chinese and English. This paper is to discuss non-equivalence of color words between Chinese and English on the two aspects and emphasizes the importance of transmitting cultural message accurately in the mutual translation between Chinese and English. Studying the cultural connotations of the words is of great importance for successful communication.

  8. Color sensing under microwaves

    Science.gov (United States)

    Choudhury, Debesh

    2013-09-01

    Inspired by recent results of artificial color due to Caulfield, we carry out intuitive experimental investigations on color sensing under microwave illumination. Experiemnts have been carried out using a Gunn diode as the microwave source and a microwave diode as a detector. More precise experimental studies have also been carried out utilizing a vector network analyzer. Preliminary results of the experiments validate the feasibility of sensing and discriminating otherwise visual colors under microwave illumination. Caulfield's presumption possibly paves the way for artificial color perception using microwaves.

  9. Weaving versus blending: a quantitative assessment of the information carrying capacities of two alternative methods for conveying multivariate data with color.

    Science.gov (United States)

    Hagh-Shenas, Haleh; Kim, Sunghee; Interrante, Victoria; Healey, Christopher

    2007-01-01

    found that participants' abilities to accurately interpret each of the individual components in a high frequency color texture typically falls off as the number of components increases from 4 to 6. We found no significant advantages, in either color blending or color weaving, to using color scales based on component hues thatare more widely separated in the L*a*b* color space. Furthermore, we found some indications that extra difficulties may arise when opponent hues are employed.

  10. Encyclopedia of color science and technology

    CERN Document Server

    2016-01-01

    The Encyclopedia of Color Science and Technology provides an authoritative single source for understanding and applying the concepts of color to all fields of science and technology, including artistic and historical aspects of color. Many topics are discussed in this timely reference, including an introduction to the science of color, and entries on the physics, chemistry and perception of color. Color is described as it relates to optical phenomena of color and continues on through colorants and materials used to modulate color and also to human vision of color. The measurement of color is provided as is colorimetry, color spaces, color difference metrics, color appearance models, color order systems and cognitive color. Other topics discussed include industrial color, color imaging, capturing color, displaying color and printing color. Descriptions of color encodings, color management, processing color and applications relating to color synthesis for computer graphics are included in this work. The Encyclo...

  11. 3-D Color Wheels

    Science.gov (United States)

    DuBois, Ann

    2010-01-01

    The blending of information from an academic class with projects from art class can do nothing but strengthen the learning power of the student. Creating three-dimensional color wheels provides the perfect opportunity to combine basic geometry knowledge with color theory. In this article, the author describes how her seventh-grade painting…

  12. Gauge color codes

    DEFF Research Database (Denmark)

    Bombin Palomo, Hector

    2015-01-01

    Color codes are topological stabilizer codes with unusual transversality properties. Here I show that their group of transversal gates is optimal and only depends on the spatial dimension, not the local geometry. I also introduce a generalized, subsystem version of color codes. In 3D they allow...

  13. Measurement of Color Texture

    NARCIS (Netherlands)

    Hoang, M.A.; Geusebroek, J.M.; Deprettere, E.F.; Belloum, A.; Heijnsdijk, J.W.J.; van der Stappen, F.

    2002-01-01

    In computer vision, measurement of image properties such as color or texture is essential. However, existing methods for measuring color and texture in combination are not well-defined neither from a measurement theoretical basis nor from a physical point of view. We propose a solid framework for th

  14. Dynamic egg color mimicry.

    Science.gov (United States)

    Hanley, Daniel; Šulc, Michal; Brennan, Patricia L R; Hauber, Mark E; Grim, Tomáš; Honza, Marcel

    2016-06-01

    Evolutionary hypotheses regarding the function of eggshell phenotypes, from solar protection through mimicry, have implicitly assumed that eggshell appearance remains static throughout the laying and incubation periods. However, recent research demonstrates that egg coloration changes over relatively short, biologically relevant timescales. Here, we provide the first evidence that such changes impact brood parasite-host eggshell color mimicry during the incubation stage. First, we use long-term data to establish how rapidly the Acrocephalus arundinaceus Linnaeus (great reed warbler) responded to natural parasitic eggs laid by the Cuculus canorus Linnaeus (common cuckoo). Most hosts rejected parasitic eggs just prior to clutch completion, but the host response period extended well into incubation (~10 days after clutch completion). Using reflectance spectrometry and visual modeling, we demonstrate that eggshell coloration in the great reed warbler and its brood parasite, the common cuckoo, changes rapidly, and the extent of eggshell color mimicry shifts dynamically over the host response period. Specifically, 4 days after being laid, the host should notice achromatic color changes to both cuckoo and warbler eggs, while chromatic color changes would be noticeable after 8 days. Furthermore, we demonstrate that the perceived match between host and cuckoo eggshell color worsened over the incubation period. These findings have important implications for parasite-host coevolution dynamics, because host egg discrimination may be aided by disparate temporal color changes in host and parasite eggs.

  15. The Colored Jones Function

    Institute of Scientific and Technical Information of China (English)

    HAN You-fa; YAN Xin-ming; LV Li-li

    2012-01-01

    In this paper,we discuss the properties of the colored Jones function of knots.Particularly,we calculate the colored Jones function of some knots(31,41,51,52).Furthermore,one can compute the Kashaev's invariants and study some properties of the Kashaev's conjecture.

  16. Plasmonic color tuning

    Science.gov (United States)

    Lee, Byoungho; Yun, Hansik; Lee, Seung-Yeol; Kim, Hwi

    2016-03-01

    In general, color filter is an optical component to permit the transmission of a specific color in cameras, displays, and microscopes. Each filter has its own unchangeable color because it is made by chemical materials such as dyes and pigments. Therefore, in order to express various colorful images in a display, one pixel should have three sub-pixels of red, green, and blue colors. Here, we suggest new plasmonic structure and method to change the color in a single pixel. It is comprised of a cavity and a metal nanoaperture. The optical cavity generally supports standing waves inside it, and various standing waves having different wavelength can be confined together in one cavity. On the other hand, although light cannot transmit sub-wavelength sized aperture, surface plasmons can propagate through the metal nanoaperture with high intensity due to the extraordinary transmission. If we combine the two structures, we can organize the spatial distribution of amplitudes according to wavelength of various standing waves using the cavity, and we can extract a light with specific wavelength and amplitude using the nanoaperture. Therefore, this cavity-aperture structure can simultaneously tune the color and intensity of the transmitted light through the single nanoaperture. We expect that the cavity-apertures have a potential for dynamic color pixels, micro-imaging system, and multiplexed sensors.

  17. The Color of Lobsters

    NARCIS (Netherlands)

    Wijk, Arjan van

    2005-01-01

    Synthesis of 13C-enriched carotenoids. Carotenoids are natural colorants, ranging in color from pale yellow to deep purple, with important biological functions. Carotenoids in the human diet have a beneficial health effect, playing a role in the prevention of cardiovascular disease and cancer. To ge

  18. List coloring with requests

    OpenAIRE

    Dvořák, Zdeněk; Norin, Sergey; Postle, Luke

    2016-01-01

    Let G be a graph with a list assignment L. Suppose a preferred color is given for some of the vertices; how many of these preferences can be respected when L-coloring G? We explore several natural questions arising in this context, and propose directions for further research.

  19. Image color reduction method for color-defective observers using a color palette composed of 20 particular colors

    Science.gov (United States)

    Sakamoto, Takashi

    2015-01-01

    This study describes a color enhancement method that uses a color palette especially designed for protan and deutan defects, commonly known as red-green color blindness. The proposed color reduction method is based on a simple color mapping. Complicated computation and image processing are not required by using the proposed method, and the method can replace protan and deutan confusion (p/d-confusion) colors with protan and deutan safe (p/d-safe) colors. Color palettes for protan and deutan defects proposed by previous studies are composed of few p/d-safe colors. Thus, the colors contained in these palettes are insufficient for replacing colors in photographs. Recently, Ito et al. proposed a p/dsafe color palette composed of 20 particular colors. The author demonstrated that their p/d-safe color palette could be applied to image color reduction in photographs as a means to replace p/d-confusion colors. This study describes the results of the proposed color reduction in photographs that include typical p/d-confusion colors, which can be replaced. After the reduction process is completed, color-defective observers can distinguish these confusion colors.

  20. Color Medical Image Analysis

    CERN Document Server

    Schaefer, Gerald

    2013-01-01

    Since the early 20th century, medical imaging has been dominated by monochrome imaging modalities such as x-ray, computed tomography, ultrasound, and magnetic resonance imaging. As a result, color information has been overlooked in medical image analysis applications. Recently, various medical imaging modalities that involve color information have been introduced. These include cervicography, dermoscopy, fundus photography, gastrointestinal endoscopy, microscopy, and wound photography. However, in comparison to monochrome images, the analysis of color images is a relatively unexplored area. The multivariate nature of color image data presents new challenges for researchers and practitioners as the numerous methods developed for monochrome images are often not directly applicable to multichannel images. The goal of this volume is to summarize the state-of-the-art in the utilization of color information in medical image analysis.

  1. Aspects of Color Superconductivity

    CERN Document Server

    Hong, D K

    2001-01-01

    I discuss some aspects of recent developments in color superconductivity in high density quark matter. I calculate the Cooper pair gap and the critical points at high density, where magnetic gluons are not screened. The ground state of high density QCD with three light flavors is shown to be a color-flavor locking state, which can be mapped into the low-density hadronic phase. The meson mass at the CFL superconductor is also calculated. The CFL color superconductor is bosonized, where the Fermi sea is identified as a $Q$-matter and the gapped quarks as topological excitations, called superqualitons, of mesons. Finally, as an application of color supercoductivity, I discuss the neutrino interactions in the CFL color superconductor.

  2. Color vision and dentistry.

    Science.gov (United States)

    Wasson, W; Schuman, N

    1992-05-01

    Color vision is a critical component of restorative and esthetic dentistry, but dentists, as a group, do not have their color vision tested at any time during their careers. A study was undertaken to ascertain the color-vision status of practicing dental personnel at the University of Tennessee, College of Dentistry. One hundred fifty individuals, 75 men and 75 women, were screened. The results corroborated the existing medical data for the general population. It was found that 9.3% of the men and none of the women exhibited color-vision defect. Since most dentists are male, this study demonstrates an area of potential weakness for some practitioners. Once a color-vision problem is found, it is simple to remedy by employing a team approach to shade matching or mechanical means of matching shades (by the practitioner). No ethnic or racial distinctions were detected, although these have been reported in other studies.

  3. Stool Color: When to Worry

    Science.gov (United States)

    Stool color: When to worry Yesterday, my stool color was bright green. Should I be concerned? Answers from Michael ... M.D. Stool comes in a range of colors. All shades of brown and even green are ...

  4. Color-avoiding percolation

    CERN Document Server

    Krause, Sebastian M; Zlatić, Vinko

    2016-01-01

    Many real world networks have groups of similar nodes which are vulnerable to the same failure or adversary. Nodes can be colored in such a way that colors encode the shared vulnerabilities. Using multiple paths to avoid these vulnerabilities can greatly improve network robustness. Color-avoiding percolation provides a theoretical framework for analyzing this scenario, focusing on the maximal set of nodes which can be connected via multiple color-avoiding paths. In this paper we extend the basic theory of color-avoiding percolation that was published in [Krause et. al., Phys. Rev. X 6 (2016) 041022]. We explicitly account for the fact that the same particular link can be part of different paths avoiding different colors. This fact was previously accounted for with a heuristic approximation. We compare this approximation with a new, more exact theory and show that the new theory is substantially more accurate for many avoided colors. Further, we formulate our new theory with differentiated node functions, as s...

  5. Colors and contact dermatitis.

    Science.gov (United States)

    Bonamonte, Domenico; Foti, Caterina; Romita, Paolo; Vestita, Michelangelo; Angelini, Gianni

    2014-01-01

    The diagnosis of skin diseases relies on several clinical signs, among which color is of paramount importance. In this review, we consider certain clinical presentations of both eczematous and noneczematous contact dermatitis in which color plays a peculiar role orientating toward the right diagnosis. The conditions that will be discussed include specific clinical-morphologic subtypes of eczematous contact dermatitis, primary melanocytic, and nonmelanocytic contact hyperchromia, black dermographism, contact chemical leukoderma, and others. Based on the physical, chemical, and biologic factors underlying a healthy skin color, the various skin shades drawing a disease picture are thoroughly debated, stressing their etiopathogenic origins and histopathologic aspects.

  6. Biological Components of Colour Preference in Infancy

    Science.gov (United States)

    Franklin, Anna; Bevis, Laura; Ling, Yazhu; Hurlbert, Anya

    2010-01-01

    Adult colour preference has been summarized quantitatively in terms of weights on the two fundamental neural processes that underlie early colour encoding: the S-(L+M) ("blue-yellow") and L-M ("red-green") cone-opponent contrast channels ( Ling, Hurlbert & Robinson, 2006; Hurlbert & Ling, 2007). Here, we investigate whether colour preference in…

  7. A new method for colors characterization of colored stainless steel using CIE and Munsell color systems

    Science.gov (United States)

    Ji, Keming; Xue, Yongqiang; Cui, Zixiang

    2015-09-01

    It is important to establish an accurate and comprehensive method of characterizing colors of colored stainless steel and understand the changing mechanism and the regularity of colors for the research, production and application of colored stainless steel. In this work, the method which combines reflectance-wavelength with both CIE and Munsell color systems is studied, the changing regularity of hue, brightness and saturation with increasing coloring potential differences is investigated, and the mechanism of color changing is discussed. The results show that by using this method the colors of colored stainless steel can be accurately and comprehensively characterized; with coloring potential differences and colored film thickness increasing, the peaks and troughs of the reflectance curves in visible region move toward long wave, causing the cyclically changing of hue and brightness; the amplitude of reflectance curves increases, resulting in growing of the saturation; the CIE 1931 coordinate curve of colors counterclockwise and cyclically changes around the equal energy light spot.

  8. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... about the members of the eye-care team . Consumer warning about the improper use of colored contact ... About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of ...

  9. The color of money

    DEFF Research Database (Denmark)

    Ásgeirsson, Árni Gunnar; Kristjánsson, Árni; Einarsdóttir, Kristin Vala;

    2014-01-01

    of attention are affected by reward, and whether the effect involves general enhancement or is specific to discrete components of attention. Observers viewed brief displays of differentially colored letters and reported their identity. Each color signified a consistent monetary value and we measured...... the accuracy of identification under different color-pairing conditions. At the end of the session, observers were paid the balance earned during the experiment. By fitting a model based on the Theory of Visual Attention (Bundesen, 1990) to the data, we estimated processing speed, selectivity, visual short......, by including conditions with color-contingent negative values. This gave an opportunity to compare high-gain with high-loss conditions. We found clear effects of value on selectivity when comparing high- and low-value conditions. When comparing equally valuable high-loss and high-gain conditions there were...

  10. Facts About Color Blindness

    Science.gov (United States)

    ... perception of its employees, such as graphic design, photography, and food quality inspection. The Farnsworth Lantern Test ... a green chalkboard when yellow chalk is used. Art classes, which require selecting appropriate colors of paint ...

  11. Color vision test

    Science.gov (United States)

    ... vision problems: Achromatopsia -- complete color blindness , seeing only shades of gray Deuteranopia -- difficulty telling the difference between red/purple and green/purple Protanopia -- difficulty telling the difference between blue/ ...

  12. Colors of the Sky.

    Science.gov (United States)

    Bohren, Craig F.; Fraser, Alistair B.

    1985-01-01

    Explains the physical principles which result in various colors of the sky. Topics addressed include: blueness, mystical properties of water vapor, ozone, fluctuation theory of scattering, variation of purity and brightness, and red sunsets and sunrises. (DH)

  13. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... shop, but 10 hours after she first put in a pair of colored contact lenses, Laura Butler of Parkersburg, W.Va., had "extreme pain in both eyes," she said. "Because I had not ...

  14. Naturally Colored Cotton

    Institute of Scientific and Technical Information of China (English)

    履之

    1994-01-01

    Instead of using dye to color cotton, an Arizona cotton breeder is letting nature do the work. Through crossbreeding, Sally Fox of Natural Cotton Colours in Wickenberg is creating plants that yield fiber in an array

  15. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... 000 per violation. "Many of the lenses found online or in beauty salons, novelty shops or in ... de contacto de color Find an Ophthalmologist Advanced Search Ask an Ophthalmologist Browse Answers Free Newsletter Get ...

  16. Food Coloring and Behavior

    OpenAIRE

    J Gordon Millichap

    1994-01-01

    The association between the ingestion of tartrazine synthetic food coloring and behavioral change in children referred for assessment of hyperactivity was investigated at the Royal Children’s Hospital, University of Melbourne, Australia.

  17. A Colorful Equatorial Wonderland

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Papua New Guinea (PNG) is one of the least visited countries in the world... a last frontier for international travelers. PNG is a colorful equatorial wonderland as well as a living example of human's culture 1000 years ago.

  18. Relighting multiple color textures

    Institute of Scientific and Technical Information of China (English)

    DIAO Chang-yu; LU Dong-ming; LIU Gang

    2005-01-01

    With the development of digital library technology, library books made of paper can be digital released and read, and Endangered Cultural Heritages can be preserved. Traditional library's contents and functions can be greatly enhanced by digital technologies. For these new library objects, the primary key problem is precisely reconstructing their 3D models. When constructing complete 3D models, multiple color texture maps are often necessary. A commonly encountered problem uncounted during fusing of textures from multiple color images is color distortion. Each texture of a single 3D model may be obtained under possibly different lighting conditions and color response of the camera. To remove any visible seam and improve color consistency between the textures while avoiding color distortion, we propose a new efficient algorithm to relight all the texture images globally,spread residual light difference, and recolor each image by homogeneous transformation. A relative illumination model was adopted to obtain the relighting function. We choose lαβ color space with minimal correlation between channels for many natural scenes, for calculating the relighting result. Looking into two overlapped images A and B, we can pairwise relight B into A's luminosity condition in two steps. We first scale B's l channel by the lA/lB ratio of the overlapped region. We can assume A and B are in a same color plane now. Then a homogeneous transformation is applied to B's α and β channels which moves B into A's hue and saturation condition. For multiple overlapped color textures, a patch based weighted global relighting method was proposed to minimize the total color difference. The pairwise relighting method was used between each two overlapped images, and the difference in every overlapped region after relighting was weighted and summed up to construct an energy value. We used Nelder-Mead method to find a minimal energy value and the relighting parameters for every image. After

  19. Color Blind Affirmative Action

    OpenAIRE

    2003-01-01

    This paper presents a conceptual framework for understanding the consequences of the widespread adoption of race-neutral alternatives' to conventional racial affirmative action policies in college admissions. A simple model of applicant competition with endogenous effort is utilized to show that, in comparison to color-conscious affirmative action, these color-blind alternatives can significantly lower the efficiency of the student selection process in equilibrium. We examine data on matricul...

  20. The Computation of Color

    Science.gov (United States)

    1989-09-01

    patches of random colors, named Mondrians after the twentieth-century Dutch painter Piet Mondrian . In one demon- stration, Land illuminates a Mondrian with...Hsien-Che Lee, for his meticulous reading of thesis drafts, insights into color science, and inspiring collaboration on the " Mondrian -sphere" ex...Heinrich for his es- sential contributions to the " Mondrian -spheres" experiments. Special thanks to Nikos for the hours and hours he spent helping me

  1. Novikov Color Algebra and Tortken Color Algebra%Novikov Color 代数与 Tortken Color 代数

    Institute of Scientific and Technical Information of China (English)

    高秀娟; 徐丽媛

    2016-01-01

    Three concepts of Novikov color algebra,Tortken color algebra and Jordan color algebra were defined,then the relations among three algebras were discussed.We gave the basic properties of Novikov color algebra and Tortken color algebra.Then we proved a Tortken color algebra with an identity element is both associative and color commutative.We also showed how to use Novikov color algebra to construct a Tortken color algebra.%给出 Novikov color 代数、Tortken color 和 Jordan color 代数的定义,并讨论它们之间的关系,证明了有单位元的 Tortken color 代数是结合的,也是 color 交换的。给出 Novikov color 代数和 Tortken color 代数的基本性质以及利用 Novikov color 代数构造 Tortken color代数的方法。

  2. Static Filtered Sky Color Constancy

    Directory of Open Access Journals (Sweden)

    Ali Alkhalifah

    2016-05-01

    Full Text Available In Computer Vision, the sky color is used for lighting correction, image color enhancement, horizon alignment, image indexing, and outdoor image classification and in many other applications. In this article, for robust color based sky segmentation and detection, usage of lighting correction for sky color detection is investigated. As such, the impact of color constancy on sky color detection algorithms is evaluated and investigated. The color correction (constancy algorithms used includes Gray-Edge (GE, Gray-World (GW, Max-RGB (MRGB and Shades-of-Gray (SG. The algorithms GE, GW, MRGB, and SG, are tested on the static filtered sky modeling. The static filter is developed in the LAB color space. This evaluation and analysis is essential for detection scenarios, especially, color based object detection in outdoor scenes. From the results, it is concluded that the color constancy before sky color detection using LAB static filters has the potential of improving sky color detection performance. However, the application of the color constancy can impart adverse effects on the detection results. For images, the color constancy algorithms depict a compact and stable representative of the sky chroma loci, however, the sky color locus might have a shifting and deviation in a particular color representation. Since the sky static filters are using the static chromatic values, different results can be obtained by applying color constancy algorithms on various datasets.

  3. Luminance contours can gate afterimage colors and 'real' colors

    NARCIS (Netherlands)

    Anstis, S.; Vergeer, M.L.T.; Lier, R.J. van

    2012-01-01

    It has long been known that colored images may elicit afterimages in complementary colors. We have already shown (Van Lier, Vergeer, & Anstis, 2009) that one and the same adapting image may result in different afterimage colors, depending on the test contours presented after the colored image. The c

  4. Color planner for designers based on color emotions

    Science.gov (United States)

    Cheng, Ka-Man; Xin, John H.; Taylor, Gail

    2002-06-01

    During the color perception process, an associated feeling or emotion is induced in our brains, and this kind of emotion is termed as 'color emotion.' The researchers in the field of color emotions have put many efforts in quantifying color emotions with the standard color specifications and evaluating the influence of hue, lightness and chroma to the color emotions of human beings. In this study, a color planner was derived according to these findings so that the correlation of color emotions and standard color specifications was clearly indicated. Since people of different nationalities usually have different color emotions as different cultural and traditional backgrounds, the subjects in this study were all native Hong Kong Chinese and the color emotion words were all written in Chinese language in the visual assessments. Through the color planner, the designers from different areas, no matter fashion, graphic, interior or web site etc., can select suitable colors for inducing target color emotions to the customers or product-users since different colors convey different meanings to them. In addition, the designers can enhance the functionality and increase the attractiveness of their designed products by selecting suitable colors.

  5. Color measurement and discrimination

    Science.gov (United States)

    Wandell, B. A.

    1985-01-01

    Theories of color measurement attempt to provide a quantative means for predicting whether two lights will be discriminable to an average observer. All color measurement theories can be characterized as follows: suppose lights a and b evoke responses from three color channels characterized as vectors, v(a) and v(b); the vector difference v(a) - v(b) corresponds to a set of channel responses that would be generated by some real light, call it *. According to theory a and b will be discriminable when * is detectable. A detailed development and test of the classic color measurement approach are reported. In the absence of a luminance component in the test stimuli, a and b, the theory holds well. In the presence of a luminance component, the theory is clearly false. When a luminance component is present discrimination judgements depend largely on whether the lights being discriminated fall in separate, categorical regions of color space. The results suggest that sensory estimation of surface color uses different methods, and the choice of method depends upon properties of the image. When there is significant luminance variation a categorical method is used, while in the absence of significant luminance variation judgments are continuous and consistant with the measurement approach.

  6. Artificial color perception using microwaves

    CERN Document Server

    Choudhury, Debesh

    2013-01-01

    We report the feasibility of artificial color perception under microwave illumination using a standard microwave source and an antenna. We have sensed transmitted microwave power through color objects and have distinguished the colors by analyzing the sensed transmitted power. Experiments are carried out using a Gunn diode as the microwave source, some colored liquids as the objects and a microwave diode as the detector. Results are presented which open up an unusual but new way of perceiving colors using microwaves.

  7. Precision of Synesthetic Color Matching Resembles That for Recollected Colors Rather than Physical Colors

    Science.gov (United States)

    Arnold, Derek H.; Wegener, Signy V.; Brown, Francesca; Mattingley, Jason B.

    2012-01-01

    Grapheme-color synesthesia is an atypical condition in which individuals experience sensations of color when reading printed graphemes such as letters and digits. For some grapheme-color synesthetes, seeing a printed grapheme triggers a sensation of color, but "hearing" the name of a grapheme does not. This dissociation allowed us to…

  8. The color "fruit": object memories defined by color.

    Science.gov (United States)

    Lewis, David E; Pearson, Joel; Khuu, Sieu K

    2013-01-01

    Most fruits and other highly color-diagnostic objects have color as a central aspect of their identity, which can facilitate detection and visual recognition. It has been theorized that there may be a large amount of overlap between the neural representations of these objects and processing involved in color perception. In accordance with this theory we sought to determine if the recognition of highly color diagnostic fruit objects could be facilitated by the visual presentation of their known color associates. In two experiments we show that color associate priming is possible, but contingent upon multiple factors. Color priming was found to be maximally effective for the most highly color diagnostic fruits, when low spatial-frequency information was present in the image, and when determination of the object's specific identity, not merely its category, was required. These data illustrate the importance of color for determining the identity of certain objects, and support the theory that object knowledge involves sensory specific systems.

  9. Color control of the multi-color printing device

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-hua; XIU Xiao-jie; ZHU Wen-hua; TANG Hong-jun

    2006-01-01

    Conventional color-printing systems often use inks of three hues, such as CMY, CMYK and CMYKLcLm, but in order to obtain more realistic color reproductions, the ink set of more than three hues has been adopted by some color-printing systems. It is difficult, however, to model the composed color with the multiple inks when the number of the output ink hues exceeds three due to the none-unique mapping between the color spaces of the CIE Lab and the multi-color printing device. In this paper, we propose a fine color-printing method for multi-color printing device with the ink set of more than three hues. The proposed approach has good color expression ability and provides fine control of the printed color. By dividing the output color space into several subspaces, our method allows one-to-one mapping between the standard color space and the multi-color output color space. It has been proved effective when applied to the digital inkjet printer-Mutoh8000.

  10. Plate Full of Color

    Centers for Disease Control (CDC) Podcasts

    2008-08-04

    The Eagle Books are a series of four books that are brought to life by wise animal characters - Mr. Eagle, Miss Rabbit, and Coyote - who engage Rain That Dances and his young friends in the joy of physical activity, eating healthy foods, and learning from their elders about health and diabetes prevention. Plate Full of Color teaches the value of eating a variety of colorful and healthy foods.  Created: 8/4/2008 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 8/5/2008.

  11. Future of color

    Science.gov (United States)

    Ladson, Jack A.; Turner, Laraine B.; Green-Armytage, Paul; Hunt, Robert W. G.

    2002-06-01

    We live in a world in which styles and technologies are nearly the same from place to place, but change daily. This changing global culture is unprecedented, and reinforced by emerging new technologies that affect us all. The Future of Color, examines new technologies, how they will affect the selection and promulgation of color in the near future, and their impact upon us. We examine this topic from many perspectives - technological, business and commercial. Most importantly, as we understand how our world is emerging, we can position ourselves strategically for tomorrow.

  12. Color appearance in stereoscopy

    Science.gov (United States)

    Gadia, Davide; Rizzi, Alessandro; Bonanomi, Cristian; Marini, Daniele; Galmonte, Alessandra; Agostini, Tiziano

    2011-03-01

    The relationship between color and lightness appearance and the perception of depth has been studied since a while in the field of perceptual psychology and psycho-physiology. It has been found that depth perception affects the final object color and lightness appearance. In the stereoscopy research field, many studies have been proposed on human physiological effects, considering e.g. geometry, motion sickness, etc., but few has been done considering lightness and color information. Goal of this paper is to realize some preliminar experiments in Virtual Reality in order to determine the effects of depth perception on object color and lightness appearance. We have created a virtual test scene with a simple 3D simultaneous contrast configuration. We have created three different versions of this scene, each with different choices of relative positions and apparent size of the objects. We have collected the perceptual responses of several users after the observation of the test scene in the Virtual Theater of the University of Milan, a VR immersive installation characterized by a semi-cylindrical screen that covers 120° of horizontal field of view from an observation distance of 3.5 m. We present a description of the experiments setup and procedure, and we discuss the obtained results.

  13. "Color-Blind" Racism.

    Science.gov (United States)

    Carr, Leslie G.

    Examining race relations in the United States from a historical perspective, this book explains how the constitution is racist and how color blindness is actually a racist ideology. It is argued that Justice Harlan, in his dissenting opinion in Plessy v. Ferguson, meant that the constitution and the law must remain blind to the existence of race…

  14. Transparency and imaginary colors

    NARCIS (Netherlands)

    Richards, W.; Koenderink, J.J.; Van Doorn, A.

    2009-01-01

    Unlike the Metelli monochrome transparencies, when overlays and their backgrounds have chromatic content, the inferred surface colors may not always be physically realizable, and are in some sense “imaginary.” In these cases, the inferred chromatic transmittance or reflectance of the overlay lies ou

  15. Dinosaurs' True Colors

    Institute of Scientific and Technical Information of China (English)

    TANG YUANKAI

    2010-01-01

    @@ On March 10,the Beijing Museum of Natural History(BMNH)announced scientists from China and abroad had decoded the full-body color patterns of a dinosaur,a small theropod named as anchiomis huxleyi,for the first time.

  16. Colorful Kindergarten Mice

    Science.gov (United States)

    Bobick, Bryna; Wheeler, Elizabeth

    2008-01-01

    Developing kindergarten lessons can be very challenging, especially at the beginning of the school year when many students are just learning to cut paper and hold crayons. The author's favorite beginning unit of the year is "mice paintings," a practical introduction to drawing, color theory, and painting. This unit also incorporates children's…

  17. Color Wheel Windows

    Science.gov (United States)

    Leonard, Stephanie

    2012-01-01

    In this article, the author describes a painting and drawing lesson which was inspired by the beautiful circular windows found in cathedrals and churches (also known as "rose windows"). This two-week lesson would reinforce both the concept of symmetry and students' understanding of the color wheel. (Contains 1 online resource.)

  18. Social Property of Colors and Translation of Color Words

    Institute of Scientific and Technical Information of China (English)

    曾慧彬

    2013-01-01

    The paper is about the social property of colors andtranslationofcolorwords.Colorsareveryimportantinour sociallife,accordingtothispaperwecanknowsomerelations aboutsocialandcolor.EspeciallyaboutthedifferencesofChinese and English color words. Through the differences, three basic translatingmethodsaregeneralized.

  19. Using Single Colors and Color Pairs to Communicate Basic Tastes

    Directory of Open Access Journals (Sweden)

    Andy T. Woods

    2016-07-01

    Full Text Available Recently, it has been demonstrated that people associate each of the basic tastes (e.g., sweet, sour, bitter, and salty with specific colors (e.g., red, green, black, and white. In the present study, we investigated whether pairs of colors (both associated with a particular taste or taste word would give rise to stronger associations relative to pairs of colors that were associated with different tastes. We replicate the findings of previous studies highlighting the existence of a robust crossmodal correspondence between individual colors and basic tastes. However, while there was evidence that pairs of colors could indeed communicate taste information more consistently than single colors, our participants took more than twice as long to match the color pairs with tastes than the single colors. Possible reasons for these results are discussed.

  20. How bees distinguish colors

    Directory of Open Access Journals (Sweden)

    Horridge A

    2015-03-01

    Full Text Available Adrian Horridge Biological Sciences, Australian National University, Canberra, ACT, Australia Abstract: Behind each facet of the compound eye, bees have photoreceptors for ultraviolet, green, and blue wavelengths that are excited by sunlight reflected from the surrounding panorama. In experiments that excluded ultraviolet, bees learned to distinguish between black, gray, white, and various colors. To distinguish two targets of differing color, bees detected, learned, and later recognized the strongest preferred inputs, irrespective of which target displayed them. First preference was the position and measure of blue reflected from white or colored areas. They also learned the positions and a measure of the green receptor modulation at vertical edges that displayed the strongest green contrast. Modulation is the receptor response to contrast and was summed over the length of a contrasting vertical edge. This also gave them a measure of angular width between outer vertical edges. Third preference was position and a measure of blue modulation. When they returned for more reward, bees recognized the familiar coincidence of these inputs at that place. They cared nothing for colors, layout of patterns, or direction of contrast, even at black/white edges. The mechanism is a new kind of color vision in which a large-field tonic blue input must coincide in time with small-field phasic modulations caused by scanning vertical edges displaying green or blue contrast. This is the kind of system to expect in medium-lowly vision, as found in insects; the next steps are fresh looks at old observations and quantitative models. Keywords: vision, honey bee, visual processing, optimum system, picture sorting

  1. Human preference for individual colors

    Science.gov (United States)

    Palmer, Stephen E.; Schloss, Karen B.

    2010-02-01

    Color preference is an important aspect of human behavior, but little is known about why people like some colors more than others. Recent results from the Berkeley Color Project (BCP) provide detailed measurements of preferences among 32 chromatic colors as well as other relevant aspects of color perception. We describe the fit of several color preference models, including ones based on cone outputs, color-emotion associations, and Palmer and Schloss's ecological valence theory. The ecological valence theory postulates that color serves an adaptive "steering' function, analogous to taste preferences, biasing organisms to approach advantageous objects and avoid disadvantageous ones. It predicts that people will tend to like colors to the extent that they like the objects that are characteristically that color, averaged over all such objects. The ecological valence theory predicts 80% of the variance in average color preference ratings from the Weighted Affective Valence Estimates (WAVEs) of correspondingly colored objects, much more variance than any of the other models. We also describe how hue preferences for single colors differ as a function of gender, expertise, culture, social institutions, and perceptual experience.

  2. A color management system for multi-colored LED lighting

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita; Thorseth, Anders; Jepsen, Jørgen;

    2015-01-01

    A new color control system is described and implemented for a five–color LED light engine, covering a wide white gamut. The system combines a new way of using pre-calibrated look-up tables and a rule-based optimization of chromaticity distance from the Planckian locus with a calibrated color sens...

  3. An innovative color LCD using three color bank scrolling backlights

    Science.gov (United States)

    Wang, Jia-Chang; Lin, Jui-Lung

    2009-02-01

    In order to improve the approach of the conventional LCD colored image display that has been using color filter, this research is to lead a unique innovative design by using three colors bank scrolling backlight. The backlight scrolling uses Light-Emitting-Diodes (LEDs) to replace the conventional cold cathode fluorescent lamp for fleetly light alternating between Red, Green, and Blue. Images with bank segments can be displayed in terms of RGB colors in time series. According to the human persistence of vision effect, a colorful image can be demonstrated. The advantages of this three color bank scrolling can provide a cost saving because there is no color-filter of the display, resolution tripling with RGB on the same pixel, and abundant in color saturation for the selection of dedicating wavelength LEDs color mixture. Practically, this research contents the experiments of three color bank scrolling, a building up of the prototype for backlight system, optics adjustment for a proper color mixture. The results of this research show the system not only could displace the color filter but also triple the resolution. Consequently, the system is practicable and can be proposed as a new innovation to LCD industry.

  4. Color Changes Mark Polymer Reactions.

    Science.gov (United States)

    Krieger, James H.

    1980-01-01

    Describes how polydiacetylenes can be used as educational aids. These polymers have conjugated backbones, which cause changes in color when the polydiacetylenes undergo various chemical and physical processes. Diagrams summarize all chemical reactions and their associated color changes. (CS)

  5. Color and appearance metrology facility

    Data.gov (United States)

    Federal Laboratory Consortium — The NIST Physical Measurement Laboratory has established the color and appearance metrology facility to support calibration services for 0°/45° colored samples, 20°,...

  6. Personalized 2D color maps

    KAUST Repository

    Waldin, Nicholas

    2016-06-24

    2D color maps are often used to visually encode complex data characteristics such as heat or height. The comprehension of color maps in visualization is affected by the display (e.g., a monitor) and the perceptual abilities of the viewer. In this paper we present a novel method to measure a user\\'s ability to distinguish colors of a two-dimensional color map on a given monitor. We show how to adapt the color map to the user and display to optimally compensate for the measured deficiencies. Furthermore, we improve user acceptance of the calibration procedure by transforming the calibration into a game. The user has to sort colors along a line in a 3D color space in a competitive fashion. The errors the user makes in sorting these lines are used to adapt the color map to his perceptual capabilities.

  7. Artificial color perception using microwaves

    OpenAIRE

    Choudhury, Debesh; Caulfield, H. John

    2013-01-01

    We report the feasibility of artificial color perception under microwave illumination using a standard microwave source and an antenna. We have sensed transmitted microwave power through color objects and have distinguished the colors by analyzing the sensed transmitted power. Experiments are carried out using a Gunn diode as the microwave source, some colored liquids as the objects and a microwave diode as the detector. Results are presented which open up an unusual but new way of perceiving...

  8. Procedures for Testing Color Vision,

    Science.gov (United States)

    1981-01-01

    uased on the principles of Helmholtz’s theory of color vision. Helmholtz (1866) had tentatively proposed that color blindness could manifest itself in...purple) specifically to detect the three proposed types of color blindness . As a result, the Holmgren test is based on an erroneous and misleading set...of color blindness categories and an unwise choice of test and match skeins. Pseudoisochromatic plates were first introduced by Stilling (1873). The

  9. PENGARUH PENGERINGAN DENGAN FAR INFRARED DRYER, OVEN VAKUM DAN FREEZE DRYER TERHADAP WARNA, KADAR TOTAL KAROTEN, BETA KAROTEN DAN VITAMIN C PADA DAUM BAYAM (Amaranthus Tricolor L. [Effect of Drying with Far Infrared Dryer, Oven Vacuum, and Freeze Dryer on the Color, Total Carotene, Beta-Carotene, and Vitamin C of Spinach Leaves (Amaranthus Tricolor L.

    Directory of Open Access Journals (Sweden)

    Ridwan Thahir2

    2005-08-01

    Full Text Available Spinach is a well known vegetable as a source of nutrition especially for is carotene. Soinach leaves need to be dried for application in product development of food like biscuit, extruded products and analysis. One the drying method that became popular is drying using infrared wave. The aim of this research was to compare the effect of blanching and drying (far infrared dryer, oven vacuum, and freeze dryer on the color, total carotene, beta-carotene, and vitamin C of spinach leaves. Blanching and drying of increased brightness, a value, and b value. The a value is shows spinach brightness in mix red-green color while b value shows mix blue-yellow. Total carotene of fresh spinach decreased by 10.47% after blanching. Drying with vacuum decreased the total carotene by 39.31% (with blanching and 31.66 (with blanching. Drying with freeze dryer decreased the beta carotene by 4.99% (with blanching and 18.60% (with blanching. Drying with FIR dryer decreased spinach total carotene by 34.90% (with blanching and 24.86% (with blanching. The beta-carotene of fresh spinach with balancing treatment decreased of by 16.53%.drying oven vacuum decreased the beta carotene by 42.80% (wiyh blanching and 18.91% (with blanching. Drying with freeze dyer decreased the beta carotene by 29.03% (with blanching the beta carotene. The decreased of beta-carotene is bigger than total carotene. Vitamin C of fresh spinach decreased by 20.35% after blanching. Drying with oven vacuum decreased of 55.77% (without blanching and 65.42% (with blanching f the vitamin C. drying with freeze dryer decreased the vitamin C by 13.21% (without blanching and 30.67% (with blanching. Meanwhile, the vitamin C of spinach after drying with FIR dyer decreased of 60.53% (without blanching and 70.29% (with blanching.

  10. Wetting in Color

    Science.gov (United States)

    Burgess, Ian Bruce

    Colorimetric litmus tests such as pH paper have enjoyed wide commercial success due to their inexpensive production and exceptional ease of use. However, expansion of colorimetry to new sensing paradigms is challenging because macroscopic color changes are seldom coupled to arbitrary differences in the physical/chemical properties of a system. In this thesis I present in detail the development of Wetting in Color Technology, focusing primarily on its application as an inexpensive and highly selective colorimetric indicator for organic liquids. The technology exploits chemically-encoded inverse-opal photonic crystals to control the infiltration of fluids to liquid-specific spatial patterns, projecting minute differences in liquids' wettability to macroscopically distinct, easy-to-visualize structural color patterns. It is shown experimentally and corroborated with theoretical modeling using percolation theory that the high selectivity of wetting, upon-which the sensitivity of the indicator relies, is caused by the highly symmetric structure of our large-area, defect-free SiO2 inverse-opals. The regular structure also produces a bright iridescent color, which disappears when infiltrated with liquid - naturally coupling the optical and fluidic responses. Surface modification protocols are developed, requiring only silanization and selective oxidation, to facilitate the deterministic design of an indicator that differentiates a broad range of liquids. The resulting tunable, built-in horizontal and vertical chemistry gradients allow the wettability threshold to be tailored to specific liquids across a continuous range, and make the readout rely only on countable color differences. As wetting is a generic fluidic phenomenon, Wetting in Color technology could be suitable for applications in authentication or identification of unknown liquids across a broad range of industries. However, the generic nature of the response also ensures chemical non-specificity. It is shown

  11. Sexual selection on color and behavior within and between cichlid populations: Implications for speciation

    Directory of Open Access Journals (Sweden)

    Michael J. PAUERS, Jeffrey S. MCKINNON

    2012-06-01

    Full Text Available Sexual selection is widely viewed as playing a central role in haplochromine cichlid speciation. Hypothetically, once divergent mate preferences evolve among populations of these fishes, reproductive isolation follows and the populations begin to behave as different species. Various studies have examined patterns of assortative mating among species and sometimes populations, but few have examined variation in directional preferences, especially among populations of the same species. We investigated mate choice behavior in two populations of Labeotropheus fuelleborni, a Lake Malawi endemic. We test whether mating preferences between populations are based on the same traits and in the same direction as preferences within populations. We examine the potential contributions of two classes of trait, color patterns and behaviors, to reproductive isolation. When females chose between either two males of their own population, or two from another, female preferences were generally similar (for the female population across the two contexts. Mate choice patterns differed between (female populations for a measure of color, but only modestly for male behavior. In a separate experiment we simultaneously offered females a male of their own population and a male from a different population. In these trials, females consistently preferred males from their own population, which were also the males that displayed more frequently than their opponents, but not necessarily those with color traits suggested to be most attractive in the previous experiment. Thus directional preferences for chroma and related aspects of color may be important when females are presented with males of otherwise similar phenotypes, but may play little role in mediating assortative mating among populations with substantially different color patterns. A preference for male behavior could play some role in speciation if males preferentially court same-population females, as we have observed

  12. Sexual selection on color and behavior within and between cichlid populations: Implications for speciation

    Institute of Scientific and Technical Information of China (English)

    Michael J.PAUERS; Jeffrey S.MCKINNON

    2012-01-01

    Sexual selection is widely viewed as playing a central role in hapiochromine cichlid speciation.Hypothetically,once divergent mate preferences evolve among populations of these fishes,reproductive isolation follows and the populations begin to behave as different species.Various studies have examined patterns of assortative mating among species and sometimes populations,but few have examined variation in directional preferences,especially among populations of the same species.We investigated mate choice behavior in two populations of Labeotropheus fuelleborni,a Lake Malawi endemic.We test whether mating.preferences between populations are based on the same traits and in the same direction as preferences within populations.We examine the potential contributions of two classes of trait,color patterns and behaviors,to reproductive isolation.When females chose between either two males of their own population,or two from another,female preferences were generally similar (for the female population) across the two contexts.Mate choice patterns differed between (female) populations for a measure of color,but only modestly for male behavior.In a separate experiment we simultaneously offered females a male of their own population and a male from a different population.In these trials,females consistently preferred males from their own population,which were also the males that displayed more frequently than their opponents,but not necessarily those with color traits suggested to be most attractive in the previous experiment.Thus directional preferences for chroma and related aspects of color may be important when females are presented with males of otherwise similar phenotypes,but may play little role in mediating assortative mating among populations with substantially different color patterns.A preference for male behavior could play some role in speciation if males preferentially court same-population females,as we have observed for the populations studied herein.

  13. Characterization of color texture: color texture based sorting of tiles

    Science.gov (United States)

    Bourada, Y.; Lafon, Dominique; Eterradossi, O.

    1998-09-01

    Many materials used by the building industry show a color texture which affects the product commercial value. This texture can be seen as the spatial arrangement of regions of acceptable color differences. This work describes an appearance based automated sorting via color texture analysis, using ceramic tiles as example. Textural analysis of the tiles digital images expressed in CIEL*a*b* color system is performed through the analysis of intrinsic features of each region and relationships between regions. Results obtained through the automated process are compared to a visual sorting which leads to calculation of application dependant color and texture tolerances.

  14. Color Addition and Subtraction Apps

    Science.gov (United States)

    Ruiz, Frances; Ruiz, Michael J.

    2015-01-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step…

  15. Color texture measurement and segmentation

    NARCIS (Netherlands)

    Hoang, M.A.; Geusebroek, J.M.; Smeulders, A.W.M.

    2005-01-01

    In computer vision, meaurement of image properties such as color or texture is essential. In this paper, we propose a solid framework for the local measurement of texture in color images. We give a physical basis for the integration of the well-known Gabor filters with the measurement of color. Our

  16. Image indexing using color correlograms

    Science.gov (United States)

    Huang, Jing; Kumar, Shanmugasundaram Ravi; Mitra, Mandar; Zhu, Wei-Jing

    2001-01-01

    A color correlogram is a three-dimensional table indexed by color and distance between pixels which expresses how the spatial correlation of color changes with distance in a stored image. The color correlogram may be used to distinguish an image from other images in a database. To create a color correlogram, the colors in the image are quantized into m color values, c.sub.i . . . c.sub.m. Also, the distance values k.epsilon.[d] to be used in the correlogram are determined where [d] is the set of distances between pixels in the image, and where dmax is the maximum distance measurement between pixels in the image. Each entry (i, j, k) in the table is the probability of finding a pixel of color c.sub.i at a selected distance k from a pixel of color c.sub.i. A color autocorrelogram, which is a restricted version of the color correlogram that considers color pairs of the form (i,i) only, may also be used to identify an image.

  17. Astronomy with the Color Blind

    Science.gov (United States)

    Smith, Donald A.; Melrose, Justyn

    2014-01-01

    The standard method to create dramatic color images in astrophotography is to record multiple black and white images, each with a different color filter in the optical path, and then tint each frame with a color appropriate to the corresponding filter. When combined, the resulting image conveys information about the sources of emission in the…

  18. Typography, Color, and Information Structure.

    Science.gov (United States)

    Keyes, Elizabeth

    1993-01-01

    Focuses on how typography and color complement and differ from each other in signaling an underlying content structure; the synergism between typography, color, and page layout (use of white space) that aids audience understanding and use; and the characteristics of typography and of color that are most important in these contexts. (SR)

  19. Can Coloring Mandalas Reduce Anxiety?

    Science.gov (United States)

    Curry, Nancy A.; Kasser, Tim

    2005-01-01

    This study examined the effectiveness of different types of art activities in the reduction of anxiety. After undergoing a brief anxiety-induction, 84 undergraduate students were randomly assigned to color a mandala, to color a plaid form, or to color on a blank piece of paper. Results demonstrated that anxiety levels declined approximately the…

  20. Image composition with color harmonization

    Institute of Scientific and Technical Information of China (English)

    Congde Wang; Rong Zhang; Fan Deng

    2009-01-01

    Image matting and color transfer are combined to achieve image composition.Firstly,digital matting is used to pull out the region of interest.Secondly,taking color harmonization into account,color transfer techniques are introduced in pasting the region onto the target image.Experimental results show that the proposed approach generates visually plea.sing composite images.

  1. COLOR- SENSITIZED SOLAR ELEMENTS

    Directory of Open Access Journals (Sweden)

    Gish R. A.

    2016-05-01

    Full Text Available Photovoltaic devices are a promising solution to the energy crisis, because they generate electricity directly from sunlight, without producing CO2. While color-sensitized batteries are the most studied element, mainly due to its low cost and high efficiency solar energy conversion into electricity. Until recently, the color-sensitized solar cells performance was less than 1%, however, the use of titanium dioxide as the anode material have greatly raised their efficiency. The advantages of titanium dioxide is primarily in the low cost, but its use provides high light capture efficiency, with external quantum efficiency (efficiency incident photon - charge, usually in the range of 60-90% using nanocrystal forms in comparison with

  2. Structural color in Myxomycetes.

    Science.gov (United States)

    Inchaussandague, Marina; Skigin, Diana; Carmaran, Cecilia; Rosenfeldt, Sonia

    2010-07-19

    In this paper we report evidence of structural color in Myxomycetes, a group of eukaryotic microorganisms with an uncertain taxonomic position. We investigated the Diachea leucopoda, which belongs to the Physarales order, Myxomycetes class, and found that its peridium -protective layer that encloses the mass of spores- is basically a corrugated layer of a transparent material, which produces a multicolored pointillistic effect, characteristic of this species. Scanning (SEM) and transmission (TEM) electron microscopy techniques have been employed to characterize the samples. A simple optical model of a planar slab is proposed to calculate the reflectance. The chromaticity coordinates are obtained, and the results confirm that the color observed is a result of an interference effect.

  3. Coloring geographical threshold graphs

    Energy Technology Data Exchange (ETDEWEB)

    Bradonjic, Milan [Los Alamos National Laboratory; Percus, Allon [Los Alamos National Laboratory; Muller, Tobias [EINDHOVEN UNIV. OF TECH

    2008-01-01

    We propose a coloring algorithm for sparse random graphs generated by the geographical threshold graph (GTG) model, a generalization of random geometric graphs (RGG). In a GTG, nodes are distributed in a Euclidean space, and edges are assigned according to a threshold function involving the distance between nodes as well as randomly chosen node weights. The motivation for analyzing this model is that many real networks (e.g., wireless networks, the Internet, etc.) need to be studied by using a 'richer' stochastic model (which in this case includes both a distance between nodes and weights on the nodes). Here, we analyze the GTG coloring algorithm together with the graph's clique number, showing formally that in spite of the differences in structure between GTG and RGG, the asymptotic behavior of the chromatic number is identical: {chi}1n 1n n / 1n n (1 + {omicron}(1)). Finally, we consider the leading corrections to this expression, again using the coloring algorithm and clique number to provide bounds on the chromatic number. We show that the gap between the lower and upper bound is within C 1n n / (1n 1n n){sup 2}, and specify the constant C.

  4. Colored Traveling Salesman Problem.

    Science.gov (United States)

    Li, Jun; Zhou, MengChu; Sun, Qirui; Dai, Xianzhong; Yu, Xiaolong

    2015-11-01

    The multiple traveling salesman problem (MTSP) is an important combinatorial optimization problem. It has been widely and successfully applied to the practical cases in which multiple traveling individuals (salesmen) share the common workspace (city set). However, it cannot represent some application problems where multiple traveling individuals not only have their own exclusive tasks but also share a group of tasks with each other. This work proposes a new MTSP called colored traveling salesman problem (CTSP) for handling such cases. Two types of city groups are defined, i.e., each group of exclusive cities of a single color for a salesman to visit and a group of shared cities of multiple colors allowing all salesmen to visit. Evidences show that CTSP is NP-hard and a multidepot MTSP and multiple single traveling salesman problems are its special cases. We present a genetic algorithm (GA) with dual-chromosome coding for CTSP and analyze the corresponding solution space. Then, GA is improved by incorporating greedy, hill-climbing (HC), and simulated annealing (SA) operations to achieve better performance. By experiments, the limitation of the exact solution method is revealed and the performance of the presented GAs is compared. The results suggest that SAGA can achieve the best quality of solutions and HCGA should be the choice making good tradeoff between the solution quality and computing time.

  5. Coloring and Guarding Arrangements

    CERN Document Server

    Bose, Prosenjit; Collette, Sébastien; Hurtado, Ferran; Korman, Matias; Langerman, Stefan; Taslakian, Perouz

    2012-01-01

    Given an arrangement of lines in the plane, what is the minimum number $c$ of colors required to color the lines so that no cell of the arrangement is monochromatic? In this paper we give bounds on the number c both for the above question, as well as some of its variations. We redefine these problems as geometric hypergraph coloring problems. If we define $\\Hlinecell$ as the hypergraph where vertices are lines and edges represent cells of the arrangement, the answer to the above question is equal to the chromatic number of this hypergraph. We prove that this chromatic number is between $\\Omega (\\log n / \\log\\log n)$. and $O(\\sqrt{n})$. Similarly, we give bounds on the minimum size of a subset $S$ of the intersections of the lines in $\\mathcal{A}$ such that every cell is bounded by at least one of the vertices in $S$. This may be seen as a problem on guarding cells with vertices when the lines act as obstacles. The problem can also be defined as the minimum vertex cover problem in the hypergraph $\\Hvertexcell$...

  6. Watermarking on Colored Images

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The great success of internet and the ease of copying anddistributing the electronic data has presented a new challenge of how to protect the digital data. Digital watermarks have been proposed as a means for copyright protection of multimedia. Unlike the traditional visible watermark, the challenge here is to introduce a digital watermark that does not alter the quality of electronic content, while being extremely robust to attack. From the angle of signal processing, the two basic requirements for an effective watermarking scheme, robustness and transparency conflict with each other. So the digital watermark is information that is imperceptibly and robustly embedded in the host data such that it can not be removed without important degradation of images quality. This paper consists of two parts. In the first part, an authentication technique by embedding digital “watermarks” into colored images is proposed. In our approach, we embed the “watermarks” with visually recognizable patterns into the images by selectively modifying the middle-frequency coefficients of the image. In the second part, the technique of hiding a colored image into another colored one is proposed. The experimental results show that the proposed techniques successfully survive image processing operations, image cropping and the JPEG lossy compression.

  7. On Dominator Colorings in Graphs

    Indian Academy of Sciences (India)

    S Arumugam; Jay Bagga; K Raja Chandrasekar

    2012-11-01

    A dominator coloring of a graph is a proper coloring of in which every vertex dominates every vertex of at least one color class. The minimum number of colors required for a dominator coloring of is called the dominator chromatic number of and is denoted by $ d(G)$. In this paper we present several results on graphs with $ d(G)=(G)$ and $ d(G)=(G)$ where $(G)$ and $(G)$ denote respectively the chromatic number and the domination number of a graph . We also prove that if $(G)$ is the Mycielskian of , then $ d(G)+1≤ d((G))≤ d(G)+2$.

  8. Color imaging fundamentals and applications

    CERN Document Server

    Reinhard, Erik; Oguz Akyuz, Ahmet; Johnson, Garrett

    2008-01-01

    This book provides the reader with an understanding of what color is, where color comes from, and how color can be used correctly in many different applications. The authors first treat the physics of light and its interaction with matter at the atomic level, so that the origins of color can be appreciated. The intimate relationship between energy levels, orbital states, and electromagnetic waves helps to explain why diamonds shimmer, rubies are red, and the feathers of the Blue Jay are blue. Then, color theory is explained from its origin to the current state of the art, including image captu

  9. Color stabilizes textbook visual processing

    Science.gov (United States)

    Paeglis, Roberts; Orlovska, Madara; Bluss, Kristaps

    2011-05-01

    We report that pages with color illustrations elicit more homogeneous duration of fixations in 12 elementary school children. For six first graders, we compared the reading of the color cover and a greyscale illustrated text page of an abcbook. For six second grade pupils, we demonstrated a color and a greyscale fairytale book page. The fixations we recorded are concordant with the duration for preschoolers reported elsewhere. Average duration of fixations on a page with color elements are shorter than on greyscale ones, 425 (SE=13.4) and 461 (18.3) ms, respectively. The correlation analysis lends support that a color page is processed differently than its greyscale version. Fixation duration for color and greyscale condition was correlated neither for text (r=.567, p=.241) nor for images (r=.517, p=.294) for the second graders. Our research suggests that color elements on textbook pages encourage emergent readers to perform better in acquisition.

  10. Structural Colors from Fano Resonances

    CERN Document Server

    Shen, Yichen; Wang, Imbert; Stelmakh, Veronika; Joannopoulos, John D; Soljacic, Marin

    2014-01-01

    Structural coloration is an interference phenomenon where colors emerge when visible light interacts with nanoscopically structured material, and has recently become a most interesting scientific and engineering topic. However, current structural color generation mechanisms either require thick (compared to the wavelength) structures or lack dynamic tunability. This report proposes a new structural color generation mechanism, that produces colors by the Fano resonance effect on thin photonic crystal slab. We experimentally realize the proposed idea by fabricating the samples that show resonance-induced colors with weak dependence on the viewing angle. Finally, we show that the resonance-induced colors can be dynamically tuned by stretching the photonic crystal slab fabricated on an elastic substrate.

  11. Color image and video enhancement

    CERN Document Server

    Lecca, Michela; Smolka, Bogdan

    2015-01-01

    This text covers state-of-the-art color image and video enhancement techniques. The book examines the multivariate nature of color image/video data as it pertains to contrast enhancement, color correction (equalization, harmonization, normalization, balancing, constancy, etc.), noise removal and smoothing. This book also discusses color and contrast enhancement in vision sensors and applications of image and video enhancement.   ·         Focuses on enhancement of color images/video ·         Addresses algorithms for enhancing color images and video ·         Presents coverage on super resolution, restoration, in painting, and colorization.

  12. A field guide to digital color

    CERN Document Server

    Stone, Maureen

    2013-01-01

    Maureen Stone's field guide to digital color presents a survey of digital color with special emphasis on those fields important for computer graphics. The book provides the foundation for understanding color and its applications, discusses color media and color management and the use of color in computer graphics, including color design and selection. The book provides a guide for anyone who wants to understand and apply digital color. An annotated bibliography provides in-depth references for further study on each topic.

  13. Evaluation of color mapping algorithms in different color spaces

    Science.gov (United States)

    Bronner, Timothée.-Florian; Boitard, Ronan; Pourazad, Mahsa T.; Nasiopoulos, Panos; Ebrahimi, Touradj

    2016-09-01

    The color gamut supported by current commercial displays is only a subset of the full spectrum of colors visible by the human eye. In High-Definition (HD) television technology, the scope of the supported colors covers 35.9% of the full visible gamut. For comparison, Ultra High-Definition (UHD) television, which is currently being deployed on the market, extends this range to 75.8%. However, when reproducing content with a wider color gamut than that of a television, typically UHD content on HD television, some original color information may lie outside the reproduction capabilities of the television. Efficient gamut mapping techniques are required in order to fit the colors of any source content into the gamut of a given display. The goal of gamut mapping is to minimize the distortion, in terms of perceptual quality, when converting video from one color gamut to another. It is assumed that the efficiency of gamut mapping depends on the color space in which it is computed. In this article, we evaluate 14 gamut mapping techniques, 12 combinations of two projection methods across six color spaces as well as R'G'B' Clipping and wrong gamut interpretation. Objective results, using the CIEDE2000 metric, show that the R'G'B' Clipping is slightly outperformed by only one combination of color space and projection method. However, analysis of images shows that R'G'B' Clipping can result in loss of contrast in highly saturated images, greatly impairing the quality of the mapped image.

  14. 7 CFR 51.892 - Color terms.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color terms. 51.892 Section 51.892 Agriculture... Standards for Grades of Table Grapes (European or Vinifera Type) 1 Definitions § 51.892 Color terms. The color terms well colored, reasonably well colored, and fairly well colored are defined in Table...

  15. Prevalent Color Extraction and Indexing

    Directory of Open Access Journals (Sweden)

    K.K.Thyagharajan

    2014-01-01

    Full Text Available Colors in an image provides tremendous amount of information. Using this color information images can be segmented, analyzed, labeled and indexed. In content based image retrieval system, color is one of the basic primitive features used. In Prevalent Color Extraction and indexing, the most extensive color on an image is identified and it is used for indexing. For implementation, Asteroideae flower family image dataset is used. It consist of more than 16,000 species, among them nearly 100 species are considered and indexed by dominating colors. To extract the most appealable color from the user defined images, the overall color of an image has to be quantized. Spatially, quantizing the color of an image to extract the prevalent color is the major objective of this paper. A combination of K-Mean and Expectation Minimization clustering algorithm called hidden-value learned K-mean clustering quantization algorithm is used to avoid the over clustering behavior of K-Mean algorithm. The experimental result shows the marginal differences between these algorithms.

  16. Spatial processing in color reproduction

    Science.gov (United States)

    Liu, Li; Yang, Yongyi; Stark, Henry

    2005-08-01

    We consider the reproduction of color subject to material and neighborhood constraints. By 'material constraints,' we mean any constraints that are applied to the amount of ink, lights, voltages, and currents that are used in the generation of color. In the first instance we consider the problem of reproducing a target color constrained by maximum additive color signals, such as in the phosphorescence process in a cathode ray tube. In the second instance we consider the more difficult problem of reproducing color subject to constraints on the maximum primary color variations in a (spatial) neighborhood. We introduce the idea of adjacent color variance (ACV) and then attempt to reproduce colors subject to an upper bound on the ACV. An algorithm that is suitable for this task is the method of vector space projections (VSP). In order to use VSP for constrained color reproduction, we use a novel approach to linearize nonlinear CIE-Lab space constraints. Experimental results are furnished that demonstrate that using the ACV as a bound helps to reduce reproduction artifacts in a color image.

  17. The color of night: surface color categorization by color defective observers under dim illuminations.

    Science.gov (United States)

    Pokorny, Joel; Lutze, Margaret; Cao, Dingcai; Zele, Andrew J

    2008-01-01

    People with normal trichromatic color vision experience variegated hue percepts under dim illuminations where only rod photoreceptors mediate vision. Here, hue perceptions were determined for persons with congenital color vision deficiencies over a wide range of light levels, including very low light levels where rods alone mediate vision. Deuteranomalous trichromats, deuteranopes and protanopes served as observers. The appearances of 24 paper color samples from the OSA Uniform Color Scales were gauged under successively dimmer illuminations from 10 to 0.0003 Lux (1.0 to -3.5 log Lux). Triads of samples were chosen representing each of eight basic color categories; "red," "pink," "orange," "yellow," "green," "blue," "purple," and "gray." Samples within each triad varied in lightness. Observers sorted samples into groups that they could categorize with specific color names. Above -0.5 log Lux, the dichromatic and anomalous trichromatic observers sorted the samples into the original representative color groups, with some exceptions. At light levels where rods alone mediate vision, the color names assigned by the deuteranomalous trichromats were similar to the color names used by color normals; higher scotopic reflectance samples were classified as blue-green-grey and lower reflectance samples as red-orange. Color names reported by the dichromats at the dimmest light levels had extensive overlap in their sample scotopic lightness distributions. Dichromats did not assign scotopic color names based on the sample scotopic lightness, as did deuteranomalous trichromats and colour-normals. We reasoned that the reduction in color gamut that a dichromat experiences at photopic light levels leads to a limited association of rod color perception with objects differing in scotopic reflectance.

  18. "Color Revolutions" and Beyond

    Institute of Scientific and Technical Information of China (English)

    Ji Zhiye; Xu Tao; Jiang Li; Da Wei; Chen Xiangyang; Ding Xiaoxing

    2005-01-01

    @@ Astring of media-coined "color revolutions" broke out in Georgia, Ukraine and Kirgyzstan one after another inside the Commonwealth of Independent States since October 2003,reminiscent of the drama of collapse of the former Soviet bloc at the turn of the 1990s. Why those upheavals came hot on the heels of the Soviet disintegration merely a dozen or so years ago? Are we expecting more Domino effects down the road? What geographical repercussions will they spark? We have invited some experts over from the China Institutes of Contemporary International Relations to air their views on these interesting issues.

  19. Coloring GPenSIM

    OpenAIRE

    2008-01-01

    The object of this report is to present a solution on how to implement color functionality in GPenSIM. Current version of GPenSIM is based on Place/Transition nets (PT-nets). When creating systems with PT-nets there are some issues when modeling large real life systems. First of all PT-nets have no data concepts. This results in extremely large nets, because the data manipulation has to be represented in the net as places and transitions. The other issue concerns the hierarc...

  20. Color Changing Hydrogen Sensors

    Science.gov (United States)

    Roberson, Luke B.; Williams, Martha; Captain, Janine E.; Mohajeri, Nahid; Raissi, Ali

    2015-01-01

    During the Space Shuttle Program, one of the most hazardous operation that occurred was the loading of liquid hydrogen (LH2) during fueling operations of the spacecraft. Due to hydrogen's low explosive limit, any amount leaked could lead to catastrophic event. Hydrogen's chemical properties make it ideal as a rocket fuel; however, the fuel is deemed unsafe for most commercial use because of the inability to easily detect the gas leaking. The increased use of hydrogen over traditional fossil fuels would reduce greenhouse gases and America's dependency on foreign oil. Therefore a technology that would improve safety at NASA and in the commercial sector while creating a new economic sector would have a huge impact to NASA's mission. The Chemochromic Detector for sensing hydrogen gas leakage is a color-changing detector that is useful in any application where it is important to know not only the presence but also the location of the hydrogen gas leak. This technology utilizes a chemochromicpigment and polymer matrix that can be molded or spun into rigid or pliable shapes useable in variable temperature environments including atmospheres of inert gas, hydrogen gas, or mixtures of gases. A change in color of the detector material indicates where gaseous hydrogen leaks are occurring. The irreversible sensor has a dramatic color change from beige to dark grey and remains dark grey after exposure. A reversible pigment changes from white to blue in the presence of hydrogen and reverts back to white in the presence of oxygen. Both versions of the sensor's pigments were comprised of a mixture of a metal oxide substrate and a hydro-chromic compound (i.e., the compound that changed color in the presence of hydrogen) and immediately notified the operator of the presence of low levels of hydrogen. The detector can be used in a variety of formats including paint, tape, caulking, injection molded parts, textiles and fabrics, composites, and films. This technology brings numerous

  1. 'Snow White' in Color

    Science.gov (United States)

    2008-01-01

    This color image taken by the Surface Stereo Imager on NASA's Phoenix Mars Lander shows the trench dubbed 'Snow White,' after further digging on the 25th Martian day, or sol, of the mission (June 19, 2008). The lander's solar panel is casting a shadow over a portion of the trench. The trench is about 5 centimeters (2 inches) deep and 30 centimeters (12 inches) long. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  2. EPSON STYLUS COLOR 580

    Institute of Scientific and Technical Information of China (English)

    侯亮

    2001-01-01

    @@ STYLUS COLOR 580打印机机身乳白色,造型小巧而活泼.上盖采用白色半透明塑料制成,和白色机身相映成趣,摆放在家中,和家里温馨的情调非常和谐.打印机全身除了一个电源接口和一个USB接口之外,没有其他任何形式的按钮或指示灯.

  3. The color of night: Surface color perception under dim illuminations.

    Science.gov (United States)

    Pokorny, Joel; Lutze, Margaret; Cao, Dingcai; Zele, Andrew J

    2006-01-01

    Several studies document rudimentary color vision under dim illumination. Here, hue perceptions of paper color samples were determined for a wide range of light levels, including very low light levels where rods alone mediate vision. The appearances of 24 paper color samples from the OSA Uniform Color Scales were gauged under successively dimmer illuminations from 10-0.0003 Lux. Triads of samples were chosen representing each of eight basic color categories; red, pink, orange, yellow, green, blue, purple, and gray. Samples within each triad varied in lightness. Observers sorted samples into groups that they could categorize with specific color names. Above 0.32 Lux, observers sorted the samples into the originally chosen color groups with few exceptions. For 0.1-0.01 Lux, the red and orange samples were usually correctly identified as either red or orange. The remaining samples tended to be grouped into two categories, associated with the scotopic sample reflectance. The lowest reflectance samples were below threshold and were named black. The higher reflectance group was named predominately as green or blue-green (three observers; the fourth observer used blue or achromatic). At the three dimmest levels (< or = 0.0032 Lux) there continued to be conspicuous color percepts. Color categories were reliably assigned based on relative sample scotopic lightness. Of the samples above threshold, those with lower reflectance were classified as red or orange (all observers) and the higher reflectance samples as green or blue-green (three observers) or achromatic or blue (the fourth observer). Rods and L-cones presumably mediated color percepts at the intermediate light levels used in the study. At the three lowest light levels there were distinct color appearances mediated exclusively by rods. We speculate that at these light levels the visual system estimates probable colors based on prior natural experience.

  4. Edge detection of color images using the HSL color space

    Science.gov (United States)

    Weeks, Arthur R.; Felix, Carlos E.; Myler, Harley R.

    1995-03-01

    Various edge detectors have been proposed as well as several different types of adaptive edge detectors, but the performance of many of these edge detectors depends on the features and the noise present in the grayscale image. Attempts have been made to extend edge detection to color images by applying grayscale edge detection methods to each of the individual red, blue, and green color components as well as to the hue, saturation, and intensity color components of the color image. The modulus 2(pi) nature of the hue color component makes its detection difficult. For example, a hue of 0 and 2(pi) yields the same color tint. Normal edge detection of a color image containing adjacent pixels with hue of 0 and 2(pi) could yield the presence of an edge when an edge is really not present. This paper presents a method of mapping the 2(pi) modulus hue space to a linear space enabling the edge detection of the hue color component using the Sobel edge detector. The results of this algorithm are compared against the edge detection methods using the red, blue, and green color components. By combining the hue edge image with the intensity and saturation edge images, more edge information is observed.

  5. A color management system for multi-colored LED lighting

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita; Thorseth, Anders; Jepsen, Jørgen;

    2015-01-01

    A new color control system is described and implemented for a five–color LED light engine, covering a wide white gamut. The system combines a new way of using pre-calibrated look-up tables and a rule-based optimization of chromaticity distance from the Planckian locus with a calibrated color sensor....... The color sensor monitors the chromaticity of the mixed light providing the correction factor for the current driver by using the generated look-up table. The long term stability and accuracy of the system will be experimentally investigated with target tolerance within a circle radius 0.0011 in the uniform...

  6. Toward a No-Reference Image Quality Assessment Using Statistics of Perceptual Color Descriptors.

    Science.gov (United States)

    Lee, Dohyoung; Plataniotis, Konstantinos N

    2016-08-01

    Analysis of the statistical properties of natural images has played a vital role in the design of no-reference (NR) image quality assessment (IQA) techniques. In this paper, we propose parametric models describing the general characteristics of chromatic data in natural images. They provide informative cues for quantifying visual discomfort caused by the presence of chromatic image distortions. The established models capture the correlation of chromatic data between spatially adjacent pixels by means of color invariance descriptors. The use of color invariance descriptors is inspired by their relevance to visual perception, since they provide less sensitive descriptions of image scenes against viewing geometry and illumination variations than luminances. In order to approximate the visual quality perception of chromatic distortions, we devise four parametric models derived from invariance descriptors representing independent aspects of color perception: 1) hue; 2) saturation; 3) opponent angle; and 4) spherical angle. The practical utility of the proposed models is examined by deploying them in our new general-purpose NR IQA metric. The metric initially estimates the parameters of the proposed chromatic models from an input image to constitute a collection of quality-aware features (QAF). Thereafter, a machine learning technique is applied to predict visual quality given a set of extracted QAFs. Experimentation performed on large-scale image databases demonstrates that the proposed metric correlates well with the provided subjective ratings of image quality over commonly encountered achromatic and chromatic distortions, indicating that it can be deployed on a wide variety of color image processing problems as a generalized IQA solution.

  7. Full Color Holographic Endoscopy

    Science.gov (United States)

    Osanlou, A.; Bjelkhagen, H.; Mirlis, E.; Crosby, P.; Shore, A.; Henderson, P.; Napier, P.

    2013-02-01

    The ability to produce color holograms from the human tissue represents a major medical advance, specifically in the areas of diagnosis and teaching. This has been achieved at Glyndwr University. In corporation with partners at Gooch & Housego, Moor Instruments, Vivid Components and peninsula medical school, Exeter, UK, for the first time, we have produced full color holograms of human cell samples in which the cell boundary and the nuclei inside the cells could be clearly focused at different depths - something impossible with a two-dimensional photographic image. This was the main objective set by the peninsula medical school at Exeter, UK. Achieving this objective means that clinically useful images essentially indistinguishable from the object human cells could be routinely recorded. This could potentially be done at the tip of a holo-endoscopic probe inside the body. Optimised recording exposure and development processes for the holograms were defined for bulk exposures. This included the optimisation of in-house recording emulsions for coating evaluation onto polymer substrates (rather than glass plates), a key step for large volume commercial exploitation. At Glyndwr University, we also developed a new version of our in-house holographic (world-leading resolution) emulsion.

  8. Natural colorants from filamentous fungi.

    Science.gov (United States)

    Torres, Fábio Aurélio Esteves; Zaccarim, Bruna Regina; de Lencastre Novaes, Letícia Celia; Jozala, Angela Faustino; Dos Santos, Carolina Alves; Teixeira, Maria Francisca Simas; Santos-Ebinuma, Valéria Carvalho

    2016-03-01

    In the last years, there is a trend towards the replacement of synthetic colorants by natural ones, mainly due to the increase of consumer demand for natural products. The natural colorants are used to enhance the appearance of pharmaceutical products, food, and different materials, making them preferable or attractive. This review intends to provide and describe a comprehensive overview of the history of colorants, from prehistory to modern time, of their market and their applications, as well as of the most important aspects of the fermentation process to obtain natural colorants. Focus is given to colorants produced by filamentous fungal species, aiming to demonstrate the importance of these microorganisms and biocompounds, highlighting the production performance to get high yields and the aspects of conclusion that should be taken into consideration in future studies about natural colorants.

  9. Bosonic colored group field theory

    Energy Technology Data Exchange (ETDEWEB)

    Ben Geloun, Joseph [Universite Paris XI, Laboratoire de Physique Theorique, Orsay Cedex (France); University of Abomey-Calavi, Cotonou (BJ). International Chair in Mathematical Physics and Applications (ICMPA-UNESCO Chair); Universite Cheikh Anta Diop, Departement de Mathematiques et Informatique, Faculte des Sciences et Techniques, Dakar (Senegal); Magnen, Jacques [Ecole Polytechnique, Centre de Physique Theorique, Palaiseau Cedex (France); Rivasseau, Vincent [Universite Paris XI, Laboratoire de Physique Theorique, Orsay Cedex (France)

    2010-12-15

    Bosonic colored group field theory is considered. Focusing first on dimension four, namely the colored Ooguri group field model, the main properties of Feynman graphs are studied. This leads to a theorem on optimal perturbative bounds of Feynman amplitudes in the ''ultraspin'' (large spin) limit. The results are generalized in any dimension. Finally, integrating out two colors we write a new representation, which could be useful for the constructive analysis of this type of models. (orig.)

  10. Color Strategies for Image Databases

    OpenAIRE

    Süsstrunk, Sabine

    2001-01-01

    In this paper, color encoding strategies for different image database applications are discussed. The color image workflow is examined in detail, and master and derivative file encoding strategies are outlined in relation to capture, maintenance, and deployment of image files. For the most common image database purposes, recommendations are given as to which type of color encoding is most suitable. Advantages and disadvantages of sensor, input-referred, output-referred, and output device spec...

  11. Estimating the colors of paintings

    OpenAIRE

    Nascimento, Sérgio M C; Linhares, João M. M., ed. lit.; João, Catarina A. R.; Amano, Kinjiro; Montagner, Cristina; Melo, Maria J.; Vilarigues, Marcia

    2015-01-01

    Observers can adjust the spectrum of illumination on paintings for optimal viewing experience. But can they adjust the colors of paintings for the best visual impression? In an experiment carried out on a calibrated color moni- tor images of four abstract paintings obtained from hyperspectral data were shown to observers that were unfamiliar with the paintings. The color volume of the images could be manipulated by rotating the volume around the axis through the average (a*, b*) point for eac...

  12. 局部颜色映射的彩色夜视算法%Color night vision algorithm based on local color mapping

    Institute of Scientific and Technical Information of China (English)

    钱小燕; 张天慈; 王帮峰; 黄圣国

    2012-01-01

    In this paper we put forward a simple and efficient color mapping method to improve the sufficiency of nearly color night vision schemes based on global statistics. First, multi-band images are fused into the three components of an RGB image in terms of a simple linear fusion strategy based on the opponent property of ON-center OFF-surround reception in biological vision. Then a color clustering method is applied to produce color fields in the fused image. The corresponding fields in the reference image are obtained by locating the pixels in the fused image and finding the corresponding pixels in the reference image. Finally, the local mapping in the simplified Lab color space optimizes the match between the night vision and the reference images. Experiments have shown that the proposed scheme can yield a night vision image with a natural daytime color appearance while also improving the speed.%针对现有基于全局统计信息的彩色夜视算法不能较好保持图像目标色彩恒常性的不足,提出一种简单有效的局部自然彩色夜视算法.首先依据人类视觉系统的中心-环绕对抗结构生成伪彩色融合图像;按照不同颜色特征对伪彩色融合图像进行聚类,分割成不同颜色域,参考自然彩色图像中对应域为与融合图像对应位置像素集合;最后在简化Lab空间实现对应域间的局部颜色映射,将参考图像颜色特征传输至融合图像.实验结果表明,本文方法使得夜视图像获得如白天参考图像般自然、真实的效果,有利于提高场景辨识能力;方法执行速度快,便于实时处理.

  13. Color 3D Reverse Engineering

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper presents a principle and a method of col or 3D laser scanning measurement. Based on the fundamental monochrome 3D measureme nt study, color information capture, color texture mapping, coordinate computati on and other techniques are performed to achieve color 3D measurement. The syste m is designed and composed of a line laser light emitter, one color CCD camera, a motor-driven rotary filter, a circuit card and a computer. Two steps in captu ring object's images in the measurement process: Firs...

  14. COLORING PROPERTIES OF WOOL FABRIC COLORED BY NEW DYESTUFFS - AZOMETHINES

    Directory of Open Access Journals (Sweden)

    DJORDJEVIC Dragan

    2016-05-01

    Full Text Available The azomethines have broad applications in food and dyestuff industries, and in analytical chemistry, catalysis and also in the field of agrochemical. These have played an influential part in the improvement of modern coordination chemistry, but also they can also be found at key points in the development of inorganic biochemistry, catalysis and also in optical materials. The present paper describes coloring properties of wool fabric colored by new dyestuffs - azomethines, derivate of isatin. Synthesizing of dyestuffs can often have one to six chromogen, which can be defined as the photoactive components that contain colored or uncolored absorbent components. In addition of monoazo, diazo, poly-azo, anthraquinone, xanthan and similar systems, the azomethines or imines, also includes to the chromogen groups. Azomethines, such as, isatin-3-hydrazone, isatin-3-thiosemicarbazone and isatin-3-phenylhydrazone, were synthesized and their coloring performance on wool fabric assessed. The synthesized azomethines showed very good substantively for wool fibers with good coloring performance according to CIEL*a*b* system which characterized quantitative and qualitative coloring property. Dyestuff 3 or isatin-3-phenylhydrazone bound to woolen textiles to a greater extent and greater intensity (minimum value of L. Dyestuff 2 or isatin-3-thiosemicarbazone linked to the minimum amount for textiles (the largest value of L. Although it must be noted that it is a lighter shade (yellow color as opposed to the dyestuff 3 (red color.

  15. Resource Letter CCV-1: Color and Color Vision.

    Science.gov (United States)

    Stuewer, Roger H., Ed.; Pease, Paul L.

    1980-01-01

    Listed are selected resource materials on color vision and the measurement and specification of the stimulus for vision, photometry, and colorimetry. The author's purpose is to equip teachers and students with an understanding of normal and abnormal color vision. References are categorized relative to content level. (Author/DS)

  16. Color the night : applying daytime colors to nighttime imagery

    NARCIS (Netherlands)

    Toet, A.

    2003-01-01

    We present a method to give (fused) multiband night-time imagery a natural day-time color appearance. For input, the method requires a false color RGB image that is produced by mapping 3 individual bands (or the first 3 principal components) of a multiband nightvision system to the respective channe

  17. Adding Texture to Color: Quantitative Analysis of Color Emotions

    NARCIS (Netherlands)

    Lucassen, M.P.; Gevers, T.; Gijsenij, A.

    2010-01-01

    What happens to color emotion responses when texture is added to color samples? To quantify this we performed an experiment in which subjects ordered samples (displayed on a computer monitor) along four scales: Warm-Cool, Masculine-Feminine, Hard-Soft and Heavy-Light. Three sample types were used: u

  18. Alice Walker's Womanism Colored in The Color Purple

    Institute of Scientific and Technical Information of China (English)

    蒋慧慧

    2009-01-01

    In her famous novel The Color Purple,Alice Walker's womanism is colored by four kinds of conseiousness-female consciousness,racial consciousness,root-seeking consciousness,and universal consciousness.It is owing to the womanism that the heroine celie grown from an abused woman to an independent selfhood.

  19. Colorful boojums at the interface of a color superconductor

    CERN Document Server

    Cipriani, Mattia; Nitta, Muneto

    2012-01-01

    We study junctions of vortices, or boojums, at the interface between color and hadronic super- conducting/superfluid phases. This type of interface could be present in the interior of neutron stars, where an inner core made of quark matter in the color-flavor-locked phase is surrounded by an outer shell of superconducting protons and superfluid neutrons. We study the fate of magnetic (proton) and superfluid (neutron) vortices as they enter the color-flavor locked phase. We find that proton vortices terminate on Dirac monopoles of the massless magnetic field, and magnetic fluxes of massive gauge field spread along the surface and are screened by surface superconducting currents. Neutron vortices, on the other hand, split into three color magnetic vortices which host confined color-magnetic monopoles when strange quark mass is taken into account. We also present a simple numerical modelization of the shape of the neutron boojum.

  20. Color of turbulence

    CERN Document Server

    Zare, Armin; Georgiou, Tryphon T

    2016-01-01

    Second-order statistics of turbulent flows can be obtained either experimentally or via direct numerical simulations. Statistics reflect fundamentals of flow physics and can be used to develop low-complexity turbulence models. Due to experimental or numerical limitations it is often the case that only partial flow statistics can be reliably known, i.e., only certain correlations between a limited number of flow field components are available. Thus, it is of interest to complete the statistical signature of the flow field in a way that is consistent with the known dynamics. This is an inverse problem and our approach utilizes stochastically-forced linearization around turbulent mean velocity profile. In general, white-in-time stochastic forcing is not sufficient to explain turbulent flow statistics. In contrast, colored-in-time forcing of the linearized equations allows for exact matching of available correlations. To accomplish this, we develop dynamical models that generate the required stochastic excitation...

  1. Wiedemann: color y exilio

    Directory of Open Access Journals (Sweden)

    Juan Gustavo Cobo Borda

    1995-01-01

    Full Text Available El exiliado mantiene viva, en la retina de la memoria, los colores de su inicial contacto con el mundo. Al nacer en Munich en 1905 e interesarse por las artes plásticas, las primeras visiones de Guillermo Wiedemann bien pudieran fijarse en los caballos azules de Franz Marc o en las remotas tierras vírgenes de ese adánico primitivismo con que los expresionistas alemanes de la nueva sensibilidad huían hacia la naturaleza, trátese del bosque verde o las cumbres recubiertas de nieve. La choza africana o lo~ archipiélagos del Pacífico donde los tótems de Gauguin todavía arden, con sensualidad ancestral, en la penumbra salvaje.

  2. False color viewing device

    Science.gov (United States)

    Kronberg, J.W.

    1992-10-20

    A viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching the user's eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage. 7 figs.

  3. Topography of Io (color)

    Science.gov (United States)

    1997-01-01

    The images used to create this color composite of Io were acquired by Galileo during its ninth orbit (C9) of Jupiter and are part of a sequence of images designed to map the topography or relief on Io and to monitor changes in the surface color due to volcanic activity. Obtaining images at low illumination angles is like taking a picture from a high altitude around sunrise or sunset. Such lighting conditions emphasize the topography of the volcanic satellite. Several mountains up to a few miles high can be seen in this view, especially near the upper right. Some of these mountains appear to be tilted crustal blocks. Most of the dark spots correspond to active volcanic centers.North is to the top of the picture which merges images obtained with the clear, red, green, and violet filters of the solid state imaging (CCD) system on NASA's Galileo spacecraft. . The resolution is 8.3 kilometers per picture element. The image was taken on June 27, 1997 at a range of 817,000 kilometers by the solid state imaging (CCD) system on NASA's Galileo spacecraft.The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  4. Color in machine vision and its application

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Color is the phenomenon of human visual perception and the module of machine vision. Color information is widely used in the areas of virtual reality and humancomputer interaction. Color is the product of a visual environment, illumination and the human brain. Research on color information representation and its processing is typically interdisciplinary. Based on our research work on human color perception and machine color vision and its application, we summarized the hotspots of color studies in recent developments and new approaches to color vision,including basic theories and the application of color information in virtual reality, content-based image retrieval, and face recognition.

  5. Color confinement multi quark resonance

    Energy Technology Data Exchange (ETDEWEB)

    Wang Fan [Department of Physics, Nanjing University, Joint Center for Particle Nuclear Physics and Cosmology, Nanjing University and Pupil Mountain Observatory, Nanjing, 210008 (China); Ping, J.L. [Department of Physics, Nanjing Normal University, Nanjing, 210097 (China); Pang, H.R. [Department of Physics, Southeast University, Nanjing, 210008 (China); Chen, L.Z. [Department of Physics, Nanjing University, Joint Center for Particle Nuclear Physics and Cosmology, Nanjing University and Pupil Mountain Observatory, Nanjing, 210008 (China)

    2007-06-15

    A new kind microscopic resonance, the color confinement multi quark resonance is proposed and studied. The quark delocalization color screening model is compared to one of the chiral quark model, the Salamanca model, and a new mechanism of the intermediate range NN interaction, the mutual distortion of interacting nucleons, is checked to be similar to the {sigma} meson exchange.

  6. Color of Meat and Poultry

    Science.gov (United States)

    ... temperature of 160 °F as measured with a food thermometer. 9. What causes iridescent colors on meats? Meat contains iron, fat, and other compounds. When light hits a slice of meat, it splits into colors like a rainbow. There are various pigments in meat compounds that can give it an ...

  7. A Quilt of Many Colors

    Science.gov (United States)

    Masse, Don

    2012-01-01

    The author discovered artist Eleanor McCain's work on "Dear Ada," an art blog he follows. McCain makes brightly colored art quilts using various rectangles and squares. She creates visual "pop" by using these shapes in a variety of sizes and bright colors. There is an interesting spatial "push and pull" that happens when looking at her quilts.…

  8. The Chemistry of Color Photography

    Science.gov (United States)

    Guida, Wayne C.; Raber, Douglas J.

    1975-01-01

    Presents several topics in color photography which can serve as an introduction of scientific concepts into the classroom, such as: photochemistry (energy transport), organic chemistry (dye formation), physics (nature of light), psychology (color perception), and engineering (isolation of different chemical processes within layers of the film).…

  9. Gold color in dental alloys.

    Science.gov (United States)

    Cameron, T

    1997-01-01

    This article will help the dental laboratory with alloy selection by exploring how the relationship among color, ductility and strength applies to gold and how color can be quantified. Because higher quality materials translate into higher profits, upselling to the dentist and patient is also discussed.

  10. 7 CFR 28.403 - Middling Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Middling Color. 28.403 Section 28.403 Agriculture..., TESTING, AND STANDARDS Standards Official Cotton Standards of the United States for the Color Grade of American Upland Cotton § 28.403 Middling Color. Middling Color is color which is within the...

  11. Portable real-time color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2008-01-01

    We developed a simple and fast lookup-table based method to derive and apply natural daylight colors to multi-band night-time images. The method deploys an optimal color transformation derived from a set of samples taken from a daytime color reference image. The colors in the resulting colorized mul

  12. 7 CFR 29.3011 - Color intensity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color intensity. 29.3011 Section 29.3011 Agriculture... Color intensity. The varying degree of saturation or chroma. Color intensity as applied to tobacco describes the strength or weakness of a specific color or hue. It is applicable to all colors...

  13. 7 CFR 51.1436 - Color classifications.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color classifications. 51.1436 Section 51.1436... STANDARDS) United States Standards for Grades of Shelled Pecans Color Classifications § 51.1436 Color classifications. (a) The skin color of pecan kernels may be described in terms of the color...

  14. Paint or color? Bursa example

    Science.gov (United States)

    Habib, Susan; Cetinturk, Nihal

    2002-06-01

    While traditional/vernacular color scheme of a city in historical regions should be protected, changes in life style reflect on cityscapes in all ways, in which the role of new materials, paints, etc. cannot be denied. Lack of architectural and urban design studies in this field added to existing countless opportunities of new technology, with the strong desire to trying those by building owners, users and contractors have caused a chaotic situation in the use of color in cities; Bursa with its historical colorful background is no exception. All these form a trial and error phase, with painted or materials applied on surfaces without a sensitive touch to transform them to color. This must be taken in mind that color with its inherent power can bind past, present and future of the city and create an urban sense of place.

  15. Color metasurfaces in industrial perspective

    DEFF Research Database (Denmark)

    Højlund-Nielsen, Emil; Kristensen, Anders

    color modification by laser ablation is briefly described. The environmental benefits are analyzed by life cycle analysis, where the high recyclability leads to reduced environmental impact compared to conventional plastic production. In summary, a promising future is anticipated for plasmonic colors......This doctoral thesis describes the utilization of color metasurfaces in an industrial perspective, where nano-scale textures and contingent post processing replace inks, dyes and pigments in plastic production. The concept of colors by structure arguably reduces the number of raw materials...... and eliminates mechanical color sorting in the recycling stage. First, the development of experimental processes, techniques and equipment is described. A single-spot electron beam lithography scheme for master pattern definition is developed, and optical characterization equipment for both laboratory...

  16. Inheritance of goat coat colors.

    Science.gov (United States)

    Adalsteinsson, S; Sponenberg, D P; Alexieva, S; Russel, A J

    1994-01-01

    Goat color inheritance was evaluated based on color description of 218 kids and their parents (10 sires, 178 dams) from mixed crosses between several goat populations in an experiment on cashmere fiber production. Altogether 10 color patterns were observed. They were postulated to be caused by 10 alleles at the Agouti locus, with the allele for white or tan color being the top dominant allele, and the nine others codominant. The bottom recessive allele, for nonagouti color, was the 11th allele at this locus. The postulated alleles are white or tan (A(wt)), black mask (A(blm)), bezoar (A(bz)), badgerface (A(b)), grey (A(g)), lightbelly (A(lb)), swiss markings (A(sm)), lateral stripes (A(ls)), mahogany (A(mh)), red cheek (A(rc)), and nonagouti (Aa). Two types of eumelanin pigment were observed, black and light brown, the latter being dominant. Recessive brown was not observed.

  17. Color Naming Experiment in Mongolian Language

    Directory of Open Access Journals (Sweden)

    Nandin-Erdene Osorjamaa

    2015-11-01

    Full Text Available There are numerous researches on color terms and names in many languages. In Mongolian language there are few doctoral theses on color naming. Cross cultural studies of color naming have demonstrated Semantic relevance in French and Mongolian color name Gerlee Sh. (2000; Comparisons of color naming across English and Mongolian Uranchimeg B. (2004; Semantic comparison between Russian and Mongolian idioms Enhdelger O. (1996; across symbolism Dulam S. (2007 and few others. Also a few articles on color naming by some Mongolian scholars are Tsevel, Ya. (1947, Baldan, L. (1979, Bazarragchaa, M. (1997 and others. Color naming studies are not sufficiently studied in Modern Mongolian. Our research is considered to be the first intended research on color naming in Modern Mongolian, because it is one part of Ph.D dissertation on color naming. There are two color naming categories in Mongolian, basic color terms and non- basic color terms. There are seven basic color terms in Mongolian. This paper aims to consider how Mongolian color names are derived from basic colors by using psycholinguistics associative experiment. It maintains the students and researchers to acquire the specific understanding of the differences and similarities of color naming in Mongolian and  English languages from the psycho-linguistic aspect. Keywords: modern Mongolian, basic color terms, non-basic color terms, associative experiment, signal word, response word, color naming

  18. 基于区域直方图统计的灰度图像色彩传递方法%A Color Transfer Method for Colorization of Grayscale Image Based on Region Histogram Statistics

    Institute of Scientific and Technical Information of China (English)

    赵源萌; 王岭雪; 金伟其; 骆媛

    2012-01-01

    A color transfer method for grayscale image colorization based on region histogram texture description is proposed in this article. First a suitable reference image is selected for the grayscale image to be colorized, and linear transformation was applied to the luminance channels of the two images in a de-correlated opponent color space. Then the pixels were matched between two images using pixel neighborhood texture features described by histogram statistics, and the color values of best matching reference image pixel were transferred to the corresponding chromatic channels of grayscale image pixel. Finally the color transferred image is transformed back to the RGB space to be displayed. The result shows that the proposed method has the advantages of high pixel matching accuracy and low computational complexity. The obtained colorized image has better natural colorful feeling than that from image using conventional color transfer methods.%应用直方图统计法描述图像的区域纹理,提出基于区域直方图纹理描述的灰度图像色彩传递处理方法.为待彩色化处理的灰度图像选定适当的参考图像,并在去相关的对立色空间对两幅图像的亮度通道作线性变换.用直方图统计法描述的像素邻域纹理特征进行图像间的像素匹配,将匹配性最佳的参考图像像素的颜色值传递给相应灰度图像像素的颜色通道,将色彩传递结果图像转换回RGB空间显示.实验结果表明:该方法能够提高像素匹配的准确性,获得色彩自然感优于常规色彩传递方法的彩色化图像;该方法运算量较小,便于实际应用.

  19. 'Clovis' in Color

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Figure 1 This approximate true-color image taken by the Mars Exploration Rover Spirit shows the rock outcrop dubbed 'Clovis.' The rock was discovered to be softer than other rocks studied so far at Gusev Crater after the rover easily ground a hole into it with its rock abrasion tool. This image was taken by the 750-, 530- and 480-nanometer filters of the rover's panoramic camera on sol 217 (August 13, 2004). Elemental Trio Found in 'Clovis' Figure 1 above shows that the interior of the rock dubbed 'Clovis' contains higher concentrations of sulfur, bromine and chlorine than basaltic, or volcanic, rocks studied so far at Gusev Crater. The data were taken by the Mars Exploration Rover Spirit's alpha particle X-ray spectrometer after the rover dug into Clovis with its rock abrasion tool. The findings might indicate that this rock was chemically altered, and that fluids once flowed through the rock depositing these elements.

  20. LOVE IS COLOR BLIND

    Institute of Scientific and Technical Information of China (English)

    陈梦扬

    2013-01-01

    <正>看完这部电影,突然想起小时候看完《辛德勒的名单》后,问过母亲一个问题:"为什么有些人要嘲笑和歧视那些与众不同的人?"母亲告诉我:"我们都是一样的,没有人应当受到责备,每个人都应当为自己而活,要始终坚信‘Love is color blind(爱无定界)’。"爱究竟有无定界?有太多故事让我们相信这句话并非纸上谈兵。《汤姆叔叔的小屋》、《美国往事》、《为黛西小姐开车》……是的,"Love"是"Listen(倾听)",是无条件无偏见地倾听对方的需求,并予以协助;是"Obligate(感恩)",需要不断地感恩,付出爱来灌

  1. Biomimetics, color, and the arts

    Science.gov (United States)

    Schenk, Franziska

    2015-03-01

    Color as dramatic, dynamic and dazzling as the iridescent hues on the wings of certain butterflies has never been encountered in the art world. Unlike and unmatched by the chemical pigments of the artists' palette, this changeable color is created by transparent, colorless nanostructures that, as with prisms, diffract and reflect light to render spectral color visible. Until now, iridescent colors, by their very nature, have defied artists' best efforts to fully capture these rainbow hues. Now, for the first time, the artist and researcher Franziska Schenk employs latest nature-inspired color-shift technology to actually simulate the iridescence of butterflies and beetles on canvas. Crucially, studying the ingenious ways in which a range of such displays are created by insects has provided the artist with vital clues on how to adapt and adopt these challenging optical nano-materials for painting. And indeed, after years of meticulous and painstaking research both in the lab and studio, the desired effect is achieved. The resulting paintings, like an iridescent insect, do in fact fluctuate in perceived color - depending on the light and viewing angle. In tracing the artist's respective biomimetic approach, the paper not only provides an insight into the new color technology's evolution and innovative artistic possibilities, but also suggests what artists can learn from nature.

  2. Symbolism of Colors in English

    Institute of Scientific and Technical Information of China (English)

    李蔚

    2013-01-01

    There are so many words to convey different colors in English. We should pay attention to not only their basic mean-ing, but also their deeply symbolized meaning. They express different meaning owing to different cultures. In western society, col-ors have their exotic symbolized meaning. This is a permanent cultural phenomenon. In the thesis, the author discusses the sym-bolic meaning of five basic colors:red, white, black, yellow and green, and the background of the symbolic meaning of each col-or.Color is very close to people’s life. It is important for people to understand the world. Colors not only have physical character, but also have rich intension and stretchy meanings. People of different nations often have different feeling about the same color as a result of their different cultural and historical background. So colors show differences between different cultures. The author dis-cusses seven main reasons that lead to the differences of colors’symbolic meaning between Chinese and western culture, such as different political systems, different historic vicissitudes, different cultural tradition and custom, different habits of thinking and way of expressing, different natural environments and living standards, different mentality, different emotion. These words are used frequently and have plenty of sentiment. What should pay more attention to is that because of the differences between differ-ent nationalities and cultural background, or different social classes, each color has its special meaning. It is active in terms of lin-guistics. That endows color words with associative meaning.

  3. Symbolic Significance of Colors in the Novel The Color Purple

    Institute of Scientific and Technical Information of China (English)

    王卓珏

    2007-01-01

    This paper mainly explains the symbolic significance of colors in the novel The Color Purple by using theory of Alice Walker's Womaism. Black,in The Color Purple stands for humbleness,blue for a life of impulse,red for liberty and hope ,purple for women's consummate happiness. And the choice of "purple" as its title ,conceives a purple centered symbolic color system,which reveals the black women's expectation for living an ideal happy life. Walker gives an expression of black women's political condition ,state of life under the racial and sexual oppression. Her intentions are to arouse women's consciousness of self and to call on them to be self-respected ,self-supported and eventually be self-liberated.

  4. Fluorescence of ceramic color standards.

    Science.gov (United States)

    Koo, Annette; Clare, John F; Nield, Kathryn M; Deadman, Andrew; Usadi, Eric

    2010-04-20

    Fluorescence has been found in color standards available for use in calibration and verification of color measuring instruments. The fluorescence is excited at wavelengths below about 600?nm and emitted above 700?nm, within the response range of silicon photodiodes, but at the edge of the response of most photomultipliers and outside the range commonly scanned in commercial colorimeters. The degree of fluorescence on two of a set of 12 glossy ceramic tiles is enough to introduce significant error when those tiles have been calibrated in one mode of measurement and are used in another. We report the nature of the fluorescence and the implications for color measurement.

  5. Effects of color and colored light on depth perception

    OpenAIRE

    Atlı, Deniz

    2010-01-01

    Ankara : The Department of Interior Architecture and Environment Design and the Institute of Economics and Social Sciences of Bilkent University, 2010. Thesis (Master's) -- Bilkent University, 2010. Includes bibliographical references leaves 75-78. The main purpose of this study is to understand the relationship between different objects and background colors, and depth perception in interior spaces. The experiment was conducted in two phases which consist of colored background...

  6. Color Energy Of A Unitary Cayley Graph

    Directory of Open Access Journals (Sweden)

    Adiga Chandrashekar

    2014-11-01

    Full Text Available Let G be a vertex colored graph. The minimum number χ(G of colors needed for coloring of a graph G is called the chromatic number. Recently, Adiga et al. [1] have introduced the concept of color energy of a graph Ec(G and computed the color energy of few families of graphs with χ(G colors. In this paper we derive explicit formulas for the color energies of the unitary Cayley graph Xn, the complement of the colored unitary Cayley graph (Xnc and some gcd-graphs.

  7. Modules Over Color Hom-Poisson Algebras

    OpenAIRE

    2014-01-01

    In this paper we introduce color Hom-Poisson algebras and show that every color Hom-associative algebra has a non-commutative Hom-Poisson algebra structure in which the Hom-Poisson bracket is the commutator bracket. Then we show that color Poisson algebras (respectively morphism of color Poisson algebras) turn to color Hom-Poisson algebras (respectively morphism of Color Hom-Poisson algebras) by twisting the color Poisson structure. Next we prove that modules over color Hom–associative algebr...

  8. Cortical color blindness is not "blindsight for color".

    Science.gov (United States)

    Heywood, C A; Kentridge, R W; Cowey, A

    1998-09-01

    Cortical color blindness, or cerebral achromatopsia, has been likened by some authors to "blindsight" for color or an instance of "covert" processing of color. Recently, it has been shown that, although such patients are unable to identify or discriminate hue differences, they nevertheless show a striking ability to process wavelength differences, which can result in preserved sensitivity to chromatic contrast and motion in equiluminant displays. Moreover, visually evoked cortical potentials can still be elicited in response to chromatic stimuli. We suggest that these demonstrations reveal intact residual processes rather than the operation of covert processes, where proficient performance is accompanied by a denial of phenomenal awareness. We sought evidence for such covert processes by conducting appropriate tests on achromatopsic subject M.S. An "indirect" test entailing measurement of reaction times for letter identification failed to reveal covert color processes. In contrast, in a forced choice oddity task for color, M.S. was unable to verbally indicate the position of the different color, but was surprisingly adept at making an appropriate eye movement to its location. This "direct" test thus revealed the possible covert use of chromatic differences.

  9. Autophagy supports color vision.

    Science.gov (United States)

    Zhou, Zhenqing; Vinberg, Frans; Schottler, Frank; Doggett, Teresa A; Kefalov, Vladimir J; Ferguson, Thomas A

    2015-01-01

    Cones comprise only a small portion of the photoreceptors in mammalian retinas. However, cones are vital for color vision and visual perception, and their loss severely diminishes the quality of life for patients with retinal degenerative diseases. Cones function in bright light and have higher demand for energy than rods; yet, the mechanisms that support the energy requirements of cones are poorly understood. One such pathway that potentially could sustain cones under basal and stress conditions is macroautophagy. We addressed the role of macroautophagy in cones by examining how the genetic block of this pathway affects the structural integrity, survival, and function of these neurons. We found that macroautophagy was not detectable in cones under normal conditions but was readily observed following 24 h of fasting. Consistent with this, starvation induced phosphorylation of AMPK specifically in cones indicating cellular starvation. Inhibiting macroautophagy in cones by deleting the essential macroautophagy gene Atg5 led to reduced cone function following starvation suggesting that cones are sensitive to systemic changes in nutrients and activate macroautophagy to maintain their function. ATG5-deficiency rendered cones susceptible to light-induced damage and caused accumulation of damaged mitochondria in the inner segments, shortening of the outer segments, and degeneration of all cone types, revealing the importance of mitophagy in supporting cone metabolic needs. Our results demonstrate that macroautophagy supports the function and long-term survival of cones providing for their unique metabolic requirements and resistance to stress. Targeting macroautophagy has the potential to preserve cone-mediated vision during retinal degenerative diseases.

  10. Color Perception and Factor Analysis.

    Science.gov (United States)

    Cartwright, Hugh

    1986-01-01

    Provides background theory and an experiment relating to chemometrics. Describes the phenomenon where solutions are dichromatic or dichromic. Discusses the difficulty students have in describing such solutions that appear to be several different colors at the same time. (TW)

  11. Riemann Geometric Color-Weak Compensationfor Individual Observers

    OpenAIRE

    Kojima, Takanori; Mochizuki, Rika; Lenz, Reiner; Chao, Jinhui

    2014-01-01

    We extend a method for color weak compensation based on the criterion of preservation of subjective color differences between color normal and color weak observers presented in [2]. We introduce a new algorithm for color weak compensation using local affine maps between color spaces of color normal and color weak observers. We show howto estimate the local affine map and how to determine correspondences between the origins of local coordinates in color spaces of color normal and color weak ob...

  12. Plasmonic Structural Colors for Plastic Consumer Products

    DEFF Research Database (Denmark)

    Højlund-Nielsen, Emil; Mortensen, N. Asger; Kristensen, Anders

    2014-01-01

    Today colorants, such as pigments or dyes, are used to color plastic-based consumer products, either as base for solid colored bulk polymer or in inks for surface decoration. After usage, the products must be mechanically sorted by color before recycling, limiting any large-scale efficient...... recycling effort. As an alternative to chemistry-based coloring, nano-scale structural coloring has been proposed to reduce the number of materials needed and to increase pattern resolution. Here colors are created by structural based light-matter interactions in the surface. Thereby, the sorting by color...... can be avoided in the recycling state. Plasmon color technology based on aluminum has recently been firmly established as a route towards structural coloring of polymeric materials. We report on the fabrication of colors by localized surface plasmon resonances (LSPR) using roll-to-roll printing...

  13. Structural color from colloidal glasses

    Science.gov (United States)

    Magkiriadou, Sofia

    When a material has inhomogeneities at a lengthscale comparable to the wavelength of light, interference can give rise to structural colors: colors that originate from the interaction of the material's microstructure with light and do not require absorbing dyes. In this thesis we study a class of these materials, called photonic glasses, where the inhomogeneities form a dense and random arrangement. Photonic glasses have angle-independent structural colors that look like those of conventional dyes. However, when this work started, there was only a handful of colors accessible with photonic glasses, mostly hues of blue. We use various types of colloidal particles to make photonic glasses, and we study, both theoretically and experimentally, how the optical properties of these glasses relate to their structure and constituent particles. Based on our observations from glasses of conventional particles, we construct a theoretical model that explains the scarcity of yellow, orange, and red photonic glasses. Guided by this model, we develop novel colloidal systems that allow a higher degree of control over structural color. We assemble glasses of soft, core-shell particles with scattering cores and transparent shells, where the resonant wavelength can be tuned independently of the reflectivity. We then encapsulate glasses of these core-shell particles into emulsion droplets of tunable size; in this system, we observe, for the first time, angle-independent structural colors that cover the entire visible spectrum. To enhance color saturation, we begin experimenting with inverse glasses, where the refractive index of the particles is lower than the refractive index of the medium, with promising results. Finally, based on our theoretical model for scattering from colloidal glasses, we begin an exploration of the color gamut that could be achieved with this technique, and we find that photonic glasses are a promising approach to a new type of long-lasting, non-toxic, and

  14. [Acquired disorders of color vision].

    Science.gov (United States)

    Lascu, Lidia; Balaş, Mihaela

    2002-01-01

    This article is a general view of acquired disorders of color vision. The revision of the best known methods and of the etiopathogenic classification is not very important in ophthalmology but on the other hand, the detection of the blue defect advertise and associated ocular pathology. There is a major interest in serious diseases as multiple sclerosis, AIDS, diabetes melitus, when the first ocular sign can be a defect in the color vision.

  15. Perceptual Representation of Color in Abstract Non-Color Word Processing

    OpenAIRE

    Aitao Lu; Ling Yang; Zhang, John X.; Yue Wu

    2012-01-01

    Three experiments showed that naming latencies were significantly shorter when the patch color was consistent with the object’s typical color relative to when they were inconsistent. Such color simulation was also found for verbs involving an object with color and words psychologically-related to color, indicating that color simulation is not limited to situations where there is a concrete, direct connection between the concept and the color information. Results from SOA manipulation indicate...

  16. Dominant color extraction based color correction for multi-view images

    Institute of Scientific and Technical Information of China (English)

    Feng Shao; Mei Yu; Gangyi Jiang

    2007-01-01

    Color information is very important in setting the style of images. In this paper, a color correction method based on dominant color extraction is proposed to eliminate the color inconsistence between multi-view images. With the theory of basic color categories, dominant colors from the categories are extracted for reference image and input image, and then the corresponding color mapping relationships are built.Experimental results show that the proposed method is quite effective.

  17. Reproduction of various colors on Jacquard textiles by only eight kinds of color wefts

    Science.gov (United States)

    Osaki, Keiji

    2002-06-01

    By making use of the information of the textile color blocks, reproduction of high-precision colors on fabrics that we call 'Color Image Fabrics' could be woven by Jacquard loom. Color components for each pixel on digitized original image are transformed into weaving data on textile by minimizing the color difference in CIEL*a*b* representation between the original image color and the simulated textile color.

  18. SRF Coloring: Stream Register File Allocation via Graph Coloring

    Institute of Scientific and Technical Information of China (English)

    Xue-Jun Yang; Yu Deng; Li Wang; Xiao-Bo Yan; Jing Du; Ying Zhang; Gui-Bin Wang; Tao Tang

    2009-01-01

    Stream Register File (SRF) is a large on-chip memory of the stream processor and its efficient management is essential for good performance. Current stream programming languages expose the management of SRF to the programmer, incurring heavy burden on the programmer and bringing difficulties to inheriting the legacy codes. SF95 is the language developed for FT64 which is the first 64-bit stream processor designed for scientific applications. SF95 conceals SRF from the programmer and leaves the management of SRF to its compiler. In this paper, we present a compiler approach named SRF Coloring to manage SRF automatically. The novelties of this paper are: first, it is the first time to use the graph coloring-based algorithm for the SRF management; second, an algorithm framework for SRF Coloring that is well suited to the FT64 architecture is proposed -- this framework is based on a well-understood graph coloring algorithm for register allocation, together with some modifications to deal with the unusual aspects of SRF problem; third, the SRF Coloring algorithm is implemented in SF95Compiler, a compiler designed for FT64 and SF95. The experimental results show that our approach represents a practical and promising solution to SRF allocation.

  19. A Color Image Edge Detection Algorithm Based on Color Difference

    Science.gov (United States)

    Zhuo, Li; Hu, Xiaochen; Jiang, Liying; Zhang, Jing

    2016-12-01

    Although image edge detection algorithms have been widely applied in image processing, the existing algorithms still face two important problems. On one hand, to restrain the interference of noise, smoothing filters are generally exploited in the existing algorithms, resulting in loss of significant edges. On the other hand, since the existing algorithms are sensitive to noise, many noisy edges are usually detected, which will disturb the subsequent processing. Therefore, a color image edge detection algorithm based on color difference is proposed in this paper. Firstly, a new operation called color separation is defined in this paper, which can reflect the information of color difference. Then, for the neighborhood of each pixel, color separations are calculated in four different directions to detect the edges. Experimental results on natural and synthetic images show that the proposed algorithm can remove a large number of noisy edges and be robust to the smoothing filters. Furthermore, the proposed edge detection algorithm is applied in road foreground segmentation and shadow removal, which achieves good performances.

  20. 7 CFR 58.329 - Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Color. 58.329 Section 58.329 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections....329 Color. Coloring, when used shall be Annatto or any color which is approved by the U.S. Food...

  1. 7 CFR 29.3025 - General color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false General color. 29.3025 Section 29.3025 Agriculture... General color. The color of tobacco considered in relation to the type as a whole. General color is distinguished from the restricted use of the term “color” within a group. It is basically related to body...

  2. 7 CFR 51.2283 - Off color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Off color. 51.2283 Section 51.2283 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) Color Requirements § 51.2283 Off color. The term “off color” is not a color classification, but shall be applied to any lot which fails to meet...

  3. 7 CFR 58.435 - Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Color. 58.435 Section 58.435 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections....435 Color. Coloring when used, shall be Annatto or any cheese or butter color which meet...

  4. A universal color image quality metric

    NARCIS (Netherlands)

    Toet, A.; Lucassen, M.P.

    2003-01-01

    We extend a recently introduced universal grayscale image quality index to a newly developed perceptually decorrelated color space. The resulting color image quality index quantifies the distortion of a processed color image relative to its original version. We evaluated the new color image quality

  5. Three-Rainbow Coloring of Split Graphs

    Institute of Scientific and Technical Information of China (English)

    胡玉梅; 刘婷婷

    2015-01-01

    After a necessary condition is given, 3-rainbow coloring of split graphs with time complexity O(m) is obtained by constructive method. The number of corresponding colors is at most 2 or 3 more than the minimum num-ber of colors needed in a 3-rainbow coloring.

  6. Basic Color Terms in Estonian Sign Language

    Science.gov (United States)

    Hollman, Liivi; Sutrop, Urmas

    2011-01-01

    The article is written in the tradition of Brent Berlin and Paul Kay's theory of basic color terms. According to this theory there is a universal inventory of eleven basic color categories from which the basic color terms of any given language are always drawn. The number of basic color terms varies from 2 to 11 and in a language having a fully…

  7. Color Perception of the Textile and Clothing

    Institute of Scientific and Technical Information of China (English)

    陈雁; 李栋高; 陈之戈

    2004-01-01

    The color perception is related to color objects, vision system and central nervous system. The methods of evaluation, classification and prediction of the color perception are investigated and analyzed in this paper. The artificial neural networks are used for color perception, clustering and predicting based on the given data obtained from both objective measurement and subjective evaluation.

  8. Graphics-System Color-Code Interface

    Science.gov (United States)

    Tulppo, J. S.

    1982-01-01

    Circuit originally developed for a flight simulator interfaces a computer graphics system with color monitor. Subsystem is intended for particular display computer (AGT-130, ADAGE Graphics Terminal) and specific color monitor (beam penetration tube--Penetron). Store-and-transmit channel is one of five in graphics/color-monitor interface. Adding 5-bit color code to existing graphics programs requires minimal programing effort.

  9. Infants' Recognition of Objects Using Canonical Color

    Science.gov (United States)

    Kimura, Atsushi; Wada, Yuji; Yang, Jiale; Otsuka, Yumiko; Dan, Ippeita; Masuda, Tomohiro; Kanazawa, So; Yamaguchi, Masami K.

    2010-01-01

    We explored infants' ability to recognize the canonical colors of daily objects, including two color-specific objects (human face and fruit) and a non-color-specific object (flower), by using a preferential looking technique. A total of 58 infants between 5 and 8 months of age were tested with a stimulus composed of two color pictures of an object…

  10. 7 CFR 51.778 - Slightly colored.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Slightly colored. 51.778 Section 51.778 Agriculture... Standards for Grades of Florida Grapefruit Definitions § 51.778 Slightly colored. Slightly colored means that except for an aggregate area of green color which does not exceed the area of a circle 2...

  11. 7 CFR 29.3505 - Brown colors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Brown colors. 29.3505 Section 29.3505 Agriculture... Type 95) § 29.3505 Brown colors. A group of colors ranging from a light brown to a dark brown. These colors vary from medium to low saturation and from medium to very low brillance. As used in...

  12. 7 CFR 51.305 - Color requirements.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color requirements. 51.305 Section 51.305 Agriculture... Standards for Grades of Apples Color Requirements § 51.305 Color requirements. In addition to the... percentage of color specified for the variety in table I appearing in this section. All apple varieties...

  13. 7 CFR 29.1006 - Color intensity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color intensity. 29.1006 Section 29.1006 Agriculture... Type 92) § 29.1006 Color intensity. The varying degree of saturation or chroma. Color intensity as applied to tobacco describes the strength or weakness of a specific color or hue. (See Elements of...

  14. 7 CFR 51.2281 - Color classifications.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color classifications. 51.2281 Section 51.2281... STANDARDS) United States Standards for Shelled English Walnuts (Juglans Regia) Color Requirements § 51.2281 Color classifications. The following classifications are provided to describe the color of any...

  15. 7 CFR 29.2504 - Brown colors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Brown colors. 29.2504 Section 29.2504 Agriculture...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2504 Brown colors. A group of colors ranging from a reddish brown to yellowish brown. These colors vary from low to medium saturation and from...

  16. 7 CFR 29.2254 - Brown colors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Brown colors. 29.2254 Section 29.2254 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... colors. A group of colors ranging from a reddish brown to yellowish brown. These colors vary from low...

  17. 7 CFR 51.2276 - Color chart.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color chart. 51.2276 Section 51.2276 Agriculture... Standards for Shelled English Walnuts (Juglans Regia) General § 51.2276 Color chart. The color chart (USDA Walnut Color Chart) to which reference is made in §§ 51.2281 and 51.2282 illustrates the four shades...

  18. A kaleidoscopic view of graph colorings

    CERN Document Server

    Zhang, Ping

    2016-01-01

    This book describes kaleidoscopic topics that have developed in the area of graph colorings. Unifying current material on graph coloring, this book describes current information on vertex and edge colorings in graph theory, including harmonious colorings, majestic colorings, kaleidoscopic colorings and binomial colorings. Recently there have been a number of breakthroughs in vertex colorings that give rise to other colorings in a graph, such as graceful labelings of graphs that have been reconsidered under the language of colorings. The topics presented in this book include sample detailed proofs and illustrations, which depicts elements that are often overlooked. This book is ideal for graduate students and researchers in graph theory, as it covers a broad range of topics and makes connections between recent developments and well-known areas in graph theory.

  19. A new Color Feature Extraction method Based on Dynamic Color Distribution Entropy of Neighbourhoods

    Directory of Open Access Journals (Sweden)

    Fatemeh Alamdar

    2011-09-01

    Full Text Available One of the important requirements in image retrieval, indexing, classification, clustering and etc. is extracting efficient features from images. The color feature is one of the most widely used visual features. Use of color histogram is the most common way for representing color feature. One of disadvantage of the color histogram is that it does not take the color spatial distribution into consideration. In this paper dynamic color distribution entropy of neighborhoods method based on color distribution entropy is presented, which effectively describes the spatial information of colors. The image retrieval results in compare to improved color distribution entropy show the acceptable efficiency of this approach.

  20. Interaction between facial expression and color

    OpenAIRE

    Kae Nakajima; Tetsuto Minami; Shigeki Nakauchi

    2017-01-01

    Facial color varies depending on emotional state, and emotions are often described in relation to facial color. In this study, we investigated whether the recognition of facial expressions was affected by facial color and vice versa. In the facial expression task, expression morph continua were employed: fear-anger and sadness-happiness. The morphed faces were presented in three different facial colors (bluish, neutral, and reddish color). Participants identified a facial expression between t...

  1. Color-Blind Racism, Color-Blind Theology, and Church Practices

    Science.gov (United States)

    Hearn, Mark

    2009-01-01

    Color-blind racism develops when persons ignore color in people and see them simply as individuals. As persons of color in racialized societies such as the United States are unequally treated on account of their color, the issue becomes a matter of faith and religious experience as religious leaders and educators, who disregard color, overlook…

  2. Hybrid Color Space Transformation to Visualize Color Constancy

    Science.gov (United States)

    Moreno, Ramón; López-Guede, José Manuel; D'Anjou, Alicia

    Color constancy and chromatic edge detection are fundamental problems in artificial vision. In this paper we present a way to provide a visualization of color constancy that works well even in dark scenes where such humans and computer vision algorithms have hard problems due to the noise. The method is an hybrid and non linear transform of the RGB image based on the assignment of the chromatic angle as the luminosity value in the HSV space. This chromatic angle is defined on the basis of the dichromatic reflection model, having thus a physical model supporting it.

  3. Creating experimental color harmony map

    Science.gov (United States)

    Chamaret, Christel; Urban, Fabrice; Lepinel, Josselin

    2014-02-01

    Starting in the 17th century with Newton, color harmony is a topic that did not reach a consensus on definition, representation or modeling so far. Previous work highlighted specific characteristics for color harmony on com- bination of color doublets or triplets by means of a human rating on a harmony scale. However, there were no investigation involving complex stimuli or pointing out how harmony is spatially located within a picture. The modeling of such concept as well as a reliable ground-truth would be of high value for the community, since the applications are wide and concern several communities: from psychology to computer graphics. We propose a protocol for creating color harmony maps from a controlled experiment. Through an eye-tracking protocol, we focus on the identification of disharmonious colors in pictures. The experiment was composed of a free viewing pass in order to let the observer be familiar with the content before a second pass where we asked "to search for the most disharmonious areas in the picture". Twenty-seven observers participated to the experiments that was composed of a total of 30 different stimuli. The high inter-observer agreement as well as a cross-validation confirm the validity of the proposed ground-truth.

  4. Natural Enhancement of Color Image

    Directory of Open Access Journals (Sweden)

    Chen Shaohua

    2010-01-01

    Full Text Available A new algorithm of Natural Enhancement of Color Image (NECI is proposed. It is inspired by multiscale Retinex model. There are four steps to realize this enhancement. At first, the image appearance is rendered by content-dependent global mapping for light cast correction, and then a modified Retinex filter is applied to enhance the local contrast. Histogram rescaling is used afterwards for normalization purpose. At last, the texture details of image are enhanced by emphasizing the high-frequency components of image using multichannel decomposition of Cortex Transform. In the contrast enhancement step, luminance channel is firstly enhanced, and then a weighing map is calculated by collecting luminance enhancement information and applied to chrominance channel in color space CIELCh which enables a proportional enhancement of chrominance. It avoids the problem of unbalanced enhancement in classical RGB independent channel operation. In this work, it is believed that image enhancement should avoid dramatic modifications to image such as light condition changes, color temperature alteration, or additional artifacts introduced or amplified. Disregarding light conditions of the scene usually leads to unnaturally sharpened images or dramatic white balance changes. In the proposed method, the ambience of image (warm or cold color impression is maintained after enhancement, and no additional light sources are added to the scene, and no halo effect and blocking effect are amplified due to overenhancement. It realizes a Natural Enhancement of Color Image. Different types of natural scene images have been tested and an encouraging performance is obtained for the proposed method.

  5. Development of colored alumilite dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Obara, Kenjiro; Shibanuma, Kiyoshi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Yagi, Toshiaki [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Yokoo, Noriko [Radiation Application Development Association, Tokai, Ibaraki (Japan)

    2003-03-01

    In the ITER (International Thermonuclear Experimental Reactor), in-vessel components such as blanket and divertor, which are installed in the vacuum vessel of the ITER, are maintained by remote handling equipment (RH equipment). The RH equipment for maintenance is operated under sever environmental conditions, such as high temperature (50{approx}100 degC), high gamma-ray radiation ({approx}1 kGy/h) in an atmosphere of inert gas or vacuum; therefore many components of the RH equipment must have a suitable radiation resistance efficiency for long time operation (10{approx}100 MGy). Typical components of the RH equipment have been extensively tested under an intensive gamma-ray radiation. Monitoring of the radiation dose of the components of the RH equipment is essential to control the operation period of the RH equipment considering radiation resistance. However, the maximum measurable radiation dose of the conventional dosimeters, such as ionization chamber, liquid, glass and plastic dosimeters are limited to be approximately 1MGy which is too low to monitor the RH equipment for the ITER. In addition, these conventional dosimeters do not involve sufficient radiation resistance against the high gamma-ray radiation as well as are not easy handling and low cost. Based on the above backgrounds, a new dosimeter with bleaching of an azo group dye to be applied to a radiation monitor has been developed for high gamma-ray radiation use. The colored alumilite dosimeter is composed of the azo group dye (-N=N-) in an anodic oxidation layer of aluminum alloy (Al{sub 2}O{sub 3}). It can monitor the radiation dose by measuring the change of the bleaching of azo dye in the Al{sub 2}O{sub 3} layer due to gamma-ray irradiation. The degree of bleaching is measured as the change of hue (color) and brightness based on the Munsell's colors with a three dimensional universe using spectrophotometer. In the tests, the dependencies such as colors, anodized layer thickness, type of azo

  6. Perceptual Color Characterization of Cameras

    Directory of Open Access Journals (Sweden)

    Javier Vazquez-Corral

    2014-12-01

    Full Text Available Color camera characterization, mapping outputs from the camera sensors to an independent color space, such as \\(XYZ\\, is an important step in the camera processing pipeline. Until now, this procedure has been primarily solved by using a \\(3 \\times 3\\ matrix obtained via a least-squares optimization. In this paper, we propose to use the spherical sampling method, recently published by Finlayson al., to perform a perceptual color characterization. In particular, we search for the \\(3 \\times 3\\ matrix that minimizes three different perceptual errors, one pixel based and two spatially based. For the pixel-based case, we minimize the CIE \\(\\Delta E\\ error, while for the spatial-based case, we minimize both the S-CIELAB error and the CID error measure. Our results demonstrate an improvement of approximately 3for the \\(\\Delta E\\ error, 7& for the S-CIELAB error and 13% for the CID error measures.

  7. Colored Tensor Models - a Review

    Directory of Open Access Journals (Sweden)

    Razvan Gurau

    2012-04-01

    Full Text Available Colored tensor models have recently burst onto the scene as a promising conceptual and computational tool in the investigation of problems of random geometry in dimension three and higher. We present a snapshot of the cutting edge in this rapidly expanding research field. Colored tensor models have been shown to share many of the properties of their direct ancestor, matrix models, which encode a theory of fluctuating two-dimensional surfaces. These features include the possession of Feynman graphs encoding topological spaces, a 1/N expansion of graph amplitudes, embedded matrix models inside the tensor structure, a resumable leading order with critical behavior and a continuum large volume limit, Schwinger-Dyson equations satisfying a Lie algebra (akin to the Virasoro algebra in two dimensions, non-trivial classical solutions and so on. In this review, we give a detailed introduction of colored tensor models and pointers to current and future research directions.

  8. Electroweak Baryogenesis and Colored Scalars

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, Timothy; /SLAC /Michigan U., MCTP; Pierce, Aaron; /Michigan U., MCTP

    2012-02-15

    We consider the 2-loop finite temperature effective potential for a Standard Model-like Higgs boson, allowing Higgs boson couplings to additional scalars. If the scalars transform under color, they contribute 2-loop diagrams to the effective potential that include gluons. These 2-loop effects are perhaps stronger than previously appreciated. For a Higgs boson mass of 115 GeV, they can increase the strength of the phase transition by as much as a factor of 3.5. It is this effect that is responsible for the survival of the tenuous electroweak baryogenesis window of the Minimal Supersymmetric Standard Model. We further illuminate the importance of these 2-loop diagrams by contrasting models with colored scalars to models with singlet scalars. We conclude that baryogenesis favors models with light colored scalars. This motivates searches for pair-produced di-jet resonances or jet(s) + = E{sub T}.

  9. Rate calculation with colored noise

    CERN Document Server

    Bartsch, Thomas; Benito, R M; Borondo, F

    2016-01-01

    The usual identification of reactive trajectories for the calculation of reaction rates requires very time-consuming simulations, particularly if the environment presents memory effects. In this paper, we develop a new method that permits the identification of reactive trajectories in a system under the action of a stochastic colored driving. This method is based on the perturbative computation of the invariant structures that act as separatrices for reactivity. Furthermore, using this perturbative scheme, we have obtained a formally exact expression for the reaction rate in multidimensional systems coupled to colored noisy environments.

  10. The crystallography of color superconductivity

    CERN Document Server

    Bowers, J A; Bowers, Jeffrey A.; Rajagopal, Krishna

    2003-01-01

    We describe the crystalline phase of color superconducting quark matter. This phase may occur in quark matter at densities relevant for compact star physics, with possible implications for glitch phenomena in pulsars. We use a Ginzburg-Landau approach to determine that the crystal has a face-centered-cubic (FCC) structure. Moreover, our results indicate that the phase is robust, with gaps, critical temperature, and free energy comparable to those of the color-flavor-locked (CFL) phase. Our calculations also predict ``crystalline superfluidity'' in ultracold gases of fermionic atoms.

  11. A color management system for multi-colored LED lighting

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita; Thorseth, Anders; Jepsen, Jørgen

    2015-01-01

    . The color sensor monitors the chromaticity of the mixed light providing the correction factor for the current driver by using the generated look-up table. The long term stability and accuracy of the system will be experimentally investigated with target tolerance within a circle radius 0.0011 in the uniform...

  12. Measuring the color of maxillofacial prosthetic material.

    Science.gov (United States)

    Hu, X; Johnston, W M; Seghi, R R

    2010-12-01

    Color information from different color-measuring systems varies during color matching in maxillofacial prosthetics. We studied the hypothesis that a non-contact measuring system and 4 contact color-measuring instruments perform comparably in accuracy and precision on measurements of pigmented maxillofacial elastomer specimens having human skin colors. Measurement comparisons in accuracy on opaque standard color patches were made in Phase I. In Phase II, the system with the best accuracy was used as the reference instrument, and comparisons in accuracy and precision on elastomer specimens were made. The CIEDE2000 color difference formula was used. Repeated-measures ANOVA with Tukey testing and linear regression analysis for CIELAB and color differences among the instruments were performed. The contact measuring systems perform differently in accuracy, possibly due to edge loss and other factors, but performed comparably in precision with the non-contact measuring instrument. This non-contact system is recommended for color measurement of maxillofacial prosthetic materials.

  13. Object color affects identification and repetition priming.

    Science.gov (United States)

    Uttl, Bob; Graf, Peter; Santacruz, Pilar

    2006-10-01

    We investigated the influence of color on the identification of both non-studied and studied objects. Participants studied black and white and color photos of common objects and memory was assessed with an identification test. Consistent with our meta-analysis of prior research, we found that objects were easier to identify from color than from black and white photos. We also found substantial priming in all conditions, and study-to-test changes in an object's color reduced the magnitude of priming. Color-specific priming effects were large for color-complex objects, but minimal for color-simple objects. The pattern and magnitude of priming effects was not influenced either by the extent to which an object always appears in the same color (i.e., whether a color is symptomatic of an object) or by the object's origin (natural versus fabricated). We discuss the implications of our findings for theoretical accounts of object perception and repetition priming.

  14. Transfer color to night vision images

    Institute of Scientific and Technical Information of China (English)

    Shaoyuan Sun; Zhongliang Jing; Gang Liu; Zhenhua Li

    2005-01-01

    @@ Natural color appearance is the key problem of color night vision field. In this paper, the color mood of daytime color image is transferred to the monochromic night vision image. This method gives the night image a natural color appearance. For each pixel in the night vision image, the best matching pixel in the color image is found based on texture similarity measure. Entropy, energy, contrast, homogeneity, and correlation features based on co-occurrence matrix are combined as texture similarity measure to find the corresponding pixels between the two images. We use a genetic algorithm (GA) to find the optimistic weighting factors assigned to the five different features. GA is also employed in searching the matching pixels to make the color transfer algorithm faster. When the best matching pixel in the color image is found, the chromaticity values are transferred to the corresponding pixel of the night vision image. The experiment results demonstrate the efficiency of this natural color transfer technique.

  15. Color extended visual cryptography using error diffusion.

    Science.gov (United States)

    Kang, InKoo; Arce, Gonzalo R; Lee, Heung-Kyu

    2011-01-01

    Color visual cryptography (VC) encrypts a color secret message into n color halftone image shares. Previous methods in the literature show good results for black and white or gray scale VC schemes, however, they are not sufficient to be applied directly to color shares due to different color structures. Some methods for color visual cryptography are not satisfactory in terms of producing either meaningless shares or meaningful shares with low visual quality, leading to suspicion of encryption. This paper introduces the concept of visual information pixel (VIP) synchronization and error diffusion to attain a color visual cryptography encryption method that produces meaningful color shares with high visual quality. VIP synchronization retains the positions of pixels carrying visual information of original images throughout the color channels and error diffusion generates shares pleasant to human eyes. Comparisons with previous approaches show the superior performance of the new method.

  16. Modeling, Measuring, and Compensating Color Weak Vision

    Science.gov (United States)

    Oshima, Satoshi; Mochizuki, Rika; Lenz, Reiner; Chao, Jinhui

    2016-06-01

    We use methods from Riemann geometry to investigate transformations between the color spaces of color-normal and color weak observers. The two main applications are the simulation of the perception of a color weak observer for a color normal observer and the compensation of color images in a way that a color weak observer has approximately the same perception as a color normal observer. The metrics in the color spaces of interest are characterized with the help of ellipsoids defined by the just-noticable-differences between color which are measured with the help of color-matching experiments. The constructed mappings are isometries of Riemann spaces that preserve the perceived color-differences for both observers. Among the two approaches to build such an isometry, we introduce normal coordinates in Riemann spaces as a tool to construct a global color-weak compensation map. Compared to previously used methods this method is free from approximation errors due to local linearizations and it avoids the problem of shifting locations of the origin of the local coordinate system. We analyse the variations of the Riemann metrics for different observers obtained from new color matching experiments and describe three variations of the basic method. The performance of the methods is evaluated with the help of semantic differential (SD) tests.

  17. Color regeneration from reflective color sensor using an artificial intelligent technique.

    Science.gov (United States)

    Saracoglu, Ömer Galip; Altural, Hayriye

    2010-01-01

    A low-cost optical sensor based on reflective color sensing is presented. Artificial neural network models are used to improve the color regeneration from the sensor signals. Analog voltages of the sensor are successfully converted to RGB colors. The artificial intelligent models presented in this work enable color regeneration from analog outputs of the color sensor. Besides, inverse modeling supported by an intelligent technique enables the sensor probe for use of a colorimetric sensor that relates color changes to analog voltages.

  18. 用于复杂场景背景减除的拮抗方向能量时空显著性%Spatiotemporal saliency based on opponent oriented energy for background subtraction in complex scenes

    Institute of Scientific and Technical Information of China (English)

    施鹍; 周越

    2012-01-01

    本文基于生物视觉启发构建了一种用于复杂场景下的无监督时空显著性检测方法.为了紧致描述场景局部动态纹理运动,首先提出分布式拮抗方向能量导出的动态纹理描述子获取局部运动信息.然后,本文探索了利用该表达结合扩展的自相似显著性框架得到时空显著性检测器.在多个极端动态背景和摄像头运动的图像序列中,利用本文提出的算法进行了背景减除实验.广泛的定性与定量实验结果表明本文方法快速且高效.在检测精度与计算代价平衡性方面,本文算法与最先进算法具有一定竞争力.%A computational unsupervised saliency model utilizing bio-inspired features for spatiotemporal saliency is presented in this paper. We first propose distributed opponent oriented energy for capturing local dynamic texture ensemble motion. Then, we integrate the derived characterization and a revised self-resemblance saliency framework. High effectiveness and efficiency of the proposed method is extensively demonstrated both qualitatively and quantitatively, for background subtraction in the cases of extremely dynamic scenes and camera jitter. In terms of the trade-off between accuracy and computation cost, our method achieved competitive results in contrast to the state-of-art algorithm.

  19. PPARs: Protectors or Opponents of Myocardial Function?

    Directory of Open Access Journals (Sweden)

    Christine J. Pol

    2015-01-01

    Full Text Available Over 5 million people in the United States suffer from the complications of heart failure (HF, which is a rapidly expanding health complication. Disorders that contribute to HF include ischemic cardiac disease, cardiomyopathies, and hypertension. Peroxisome proliferator-activated receptors (PPARs are members of the nuclear receptor family. There are three PPAR isoforms: PPARα, PPARγ, and PPARδ. They can be activated by endogenous ligands, such as fatty acids, as well as by pharmacologic agents. Activators of PPARs are used for treating several metabolic complications, such as diabetes and hyperlipidemia that are directly or indirectly associated with HF. However, some of these drugs have adverse effects that compromise cardiac function. This review article aims to summarize the current basic and clinical research findings of the beneficial or detrimental effects of PPAR biology on myocardial function.

  20. On Einstein's opponents, and other crackpots

    NARCIS (Netherlands)

    van Dongen, J.A.E.F.

    2010-01-01

    Einsteins Gegner: Die öffentliche Kontroverse um die Relativitätstheorie in den 1920er Jahren, Milena Wazeck. Campus Verlag, pp. 429, EUR 39.90. ISBN: 978-3593389141 “This world is a strange madhouse. Currently, every coachman and every waiter is debating whether relativity theory is correct. Belief

  1. Digital color management in full-color holographic three-dimensional printer.

    Science.gov (United States)

    Yang, Fei; Murakami, Yuri; Yamaguchi, Masahiro

    2012-07-01

    We propose a new method of color management for a full-color holographic, three-dimensional (3D) printer, which produces a volume reflection holographic stereogram using red, green, and blue three-color lasers. For natural color management in the holographic 3D printer, we characterize its color reproduction characteristics based on the spectral measurement of reproduced light. Then the color conversion formula, which comprises a one-dimensional lookup table and a 3×3 matrix, was derived from the measurement data. The color reproducibility was evaluated by printing a color chart hologram, and the average CIELAB ΔE=13.19 is fairly small.

  2. Digital color acquisition, perception, coding and rendering

    CERN Document Server

    Fernandez-Maloigne, Christine; Macaire, Ludovic

    2013-01-01

    In this book the authors identify the basic concepts and recent advances in the acquisition, perception, coding and rendering of color. The fundamental aspects related to the science of colorimetry in relation to physiology (the human visual system) are addressed, as are constancy and color appearance. It also addresses the more technical aspects related to sensors and the color management screen. Particular attention is paid to the notion of color rendering in computer graphics. Beyond color, the authors also look at coding, compression, protection and quality of color images and videos.

  3. Bright color reflective displays with interlayer reflectors

    Science.gov (United States)

    Kitson, Stephen; Geisow, Adrian; Rudin, John; Taphouse, Tim

    2011-08-01

    A good solution to the reflective display of color has been a major challenge for the display industry, with very limited color gamuts demonstrated to date. Conventional side-by-side red, green and blue color filters waste two-thirds of incident light. The alternative of stacking cyan, magenta and yellow layers is also challenging -- a 10% loss per layer compounds to nearly 50% overall. Here we demonstrate an architecture that interleaves absorbing-to-clear shutters with matched wavelength selective reflectors. This increases color gamut by reducing losses and more cleanly separating the color channels, and gives much wider choice of electro-optic colorants.

  4. On the Color Dipole Picture

    CERN Document Server

    Schildknecht, Dieter

    2016-01-01

    We give a brief representation of the theoretical results from the color dipole picture, covering the total photoabsorption cross section, high-energy $J/\\psi$ photoproduction with respect to recent experimental data from the LHCb Collaboration at CERN, and ultra-high energy neutrino scattering, relevant for the ICE-CUBE experiment.

  5. Color management in textile application

    Science.gov (United States)

    De Lucia, Maurizio; Vannucci, Massimiliano; Buonopane, Massimo; Fabroni, Cosimo; Fabrini, Francesco

    2002-03-01

    The aim of this research was to study a system of acquisition and processing of images capable of confronting colored wool with a reference specimen, in order to define the conformity using objective parameters. The first step of the research was to comprise and to analyze in depth the problem: there has been numerous implications of technical, physical, cultural, biological and also psychological character, that come down from the attempt of giving a quantitative appraisal to the color. In the scene of the national and international scientific and technological research, little has been made as regards measurement of color through digital processing of the images through linear CCD. The reason is fundamentally of technological nature: only during the last years we found the presence on the market of low cost equipment capable of acquiring and processing images with adequate performances and qualities. The job described has permitted to create a first prototype of system for the color measuring with use of CCD linear devices. -Hardware identification to carry out a series of tests and experiments in laboratory. -Verification of such device in a textile facility. -Statistics analysis of the collected data and of the employed models.

  6. Color prediction in textile application

    Science.gov (United States)

    De Lucia, Maurizio; Buonopane, Massimo

    2004-09-01

    Nowadays production systems of fancy yarns for knits allow the creation of extremely complex products in which many effects are obtained by means of color alteration. Current production technique consists in defining type and quantity of fibers by making preliminary samples. This samples are then compared with a reference one. This comparison is based on operator experience. Many samples are required in order to achieve a sample similar to the reference one. This work requires time and then additional costs for a textile manufacturer. In addition, the methodology is subjective. Nowadays, spectrophotometers are the only devices that seem to be able to provide objective indications. They are based on a spectral analysis of the light reflected by the knit material. In this paper the study of a new method for color evaluation of a mix of wool fibers with different colors is presented. First of all fiber characterization were carried out through scattering and absorption coefficients using the Kubelka-Munk theory. Then the estimated color was compared with a reference item, in order to define conformity by means of objective parameters. Finally, theoretical characterization was compared with the measured quantity. This allowed estimation of prediction quality.

  7. Isocentric color saliency in images

    NARCIS (Netherlands)

    Valenti, R.; Sebe, N.; Gevers, T.

    2009-01-01

    In this paper we propose a novel computational method to infer visual saliency in images. The computational method is based on the idea that salient objects should have local characteristics that are different than the rest of the scene, being edges, color or shape, and that these characteristics ca

  8. At the Speed of Color.

    Science.gov (United States)

    Campbell, Meghan A

    2016-01-01

    Tied up with a (rain)bow: Looking ahead to 2016, important changes are underway at ChemBioChem. The elimination of color charges and accelerated publication times keep ChemBioChem at the forefront of chemical biology. We also enjoy a look back at the highlights of 2015 and upcoming changes to the editorial office and board.

  9. Nylon Fashion to Be Colorful

    Institute of Scientific and Technical Information of China (English)

    By Flora Zhao

    2012-01-01

    The thematic exhibition named "colorful life, fashionable nylon" will strike a pose on the stage of China International Trade Fair for Fibers and Yarns from March 29th to March 31st this year, delivering the fashion pulse of Chinese nylon development. Since 2007, the productivity

  10. Neural locus of color afterimages.

    Science.gov (United States)

    Zaidi, Qasim; Ennis, Robert; Cao, Dingcai; Lee, Barry

    2012-02-07

    After fixating on a colored pattern, observers see a similar pattern in complementary colors when the stimulus is removed [1-6]. Afterimages were important in disproving the theory that visual rays emanate from the eye, in demonstrating interocular interactions, and in revealing the independence of binocular vision from eye movements. Afterimages also prove invaluable in exploring selective attention, filling in, and consciousness. Proposed physiological mechanisms for color afterimages range from bleaching of cone photopigments to cortical adaptation [4-9], but direct neural measurements have not been reported. We introduce a time-varying method for evoking afterimages, which provides precise measurements of adaptation and a direct link between visual percepts and neural responses [10]. We then use in vivo electrophysiological recordings to show that all three classes of primate retinal ganglion cells exhibit subtractive adaptation to prolonged stimuli, with much slower time constants than those expected of photoreceptors. At the cessation of the stimulus, ganglion cells generate rebound responses that can provide afterimage signals for later neurons. Our results indicate that afterimage signals are generated in the retina but may be modified like other retinal signals by cortical processes, so that evidence presented for cortical generation of color afterimages is explainable by spatiotemporal factors that modify all signals.

  11. Illustrating Chromatography with Colorful Proteins

    Science.gov (United States)

    Lefebvre, Brian G.; Farrell, Stephanie; Dominiak, Richard S.

    2007-01-01

    Advances in biology are prompting new discoveries in the biotechnology, pharmaceutical, medical technology, and chemical industries. This paper presents a detailed description of an anion exchange chromatography experiment using a pair of colorful proteins and summarizes the effect of operating parameters on protein separation. This experiment…

  12. 7 CFR 28.415 - Low Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Low Middling Light Spotted Color. 28.415 Section 28... Spotted Color. Low Middling Light Spotted Color is color which in spot or color, or both, is between Low Middling Color and Low Middling Spotted Color....

  13. 7 CFR 28.412 - Strict Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strict Middling Light Spotted Color. 28.412 Section 28... Light Spotted Color. Strict Middling Light Spotted Color is color which in spot or color, or both, is between Strict Middling Color and Strict Middling Spotted Color....

  14. 7 CFR 28.413 - Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Middling Light Spotted Color. 28.413 Section 28.413... Spotted Color. Middling Light Spotted Color is color which in spot or color, or both, is between Middling Color and Middling Spotted Color....

  15. 7 CFR 28.411 - Good Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Good Middling Light Spotted Color. 28.411 Section 28... Light Spotted Color. Good Middling Light Spotted Color is color which in spot or color, or both, is between Good Middling Color and Good Middling Spotted Color....

  16. Color back projection for fruit maturity evaluation

    Science.gov (United States)

    Zhang, Dong; Lee, Dah-Jye; Desai, Alok

    2013-12-01

    In general, fruits and vegetables such as tomatoes and dates are harvested before they fully ripen. After harvesting, they continue to ripen and their color changes. Color is a good indicator of fruit maturity. For example, tomatoes change color from dark green to light green and then pink, light red, and dark red. Assessing tomato maturity helps maximize its shelf life. Color is used to determine the length of time the tomatoes can be transported. Medjool dates change color from green to yellow, and the orange, light red and dark red. Assessing date maturity helps determine the length of drying process to help ripen the dates. Color evaluation is an important step in the processing and inventory control of fruits and vegetables that directly affects profitability. This paper presents an efficient color back projection and image processing technique that is designed specifically for real-time maturity evaluation of fruits. This color processing method requires very simple training procedure to obtain the frequencies of colors that appear in each maturity stage. This color statistics is used to back project colors to predefined color indexes. Fruit maturity is then evaluated by analyzing the reprojected color indexes. This method has been implemented and used for commercial production.

  17. Color Calibration for Colorized Vision System with Digital Sensor and LED Array Illuminator

    Directory of Open Access Journals (Sweden)

    Zhenmin Zhu

    2016-01-01

    Full Text Available Color measurement by the colorized vision system is a superior method to achieve the evaluation of color objectively and continuously. However, the accuracy of color measurement is influenced by the spectral responses of digital sensor and the spectral mismatch of illumination. In this paper, two-color vision system illuminated by digital sensor and LED array, respectively, is presented. The Polynomial-Based Regression method is applied to solve the problem of color calibration in the sRGB and CIE  L⁎a⁎b⁎ color spaces. By mapping the tristimulus values from RGB to sRGB color space, color difference between the estimated values and the reference values is less than 3ΔE. Additionally, the mapping matrix ΦRGB→sRGB has proved a better performance in reducing the color difference, and it is introduced subsequently into the colorized vision system proposed for a better color measurement. Necessarily, the printed matter of clothes and the colored ceramic tile are chosen as the application experiment samples of our colorized vision system. As shown in the experimental data, the average color difference of images is less than 6ΔE. It indicates that a better performance of color measurement is obtained via the colorized vision system proposed.

  18. Color Vision Defects: What Teachers Should Know.

    Science.gov (United States)

    Lewis, Barbara A.; And Others

    1990-01-01

    Discusses the nature of color vision defects as they relate to reading instruction. Suggests ways that teachers can adapt instruction to help provide maximal learning opportunities for the color deficient child. (RS)

  19. 7 CFR 51.764 - Well colored.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... fruit has characteristic color for the variety with practically no trace of green color....

  20. Angle-independent structural colors of silicon

    DEFF Research Database (Denmark)

    Højlund-Nielsen, Emil; Weirich, Johannes; Nørregaard, Jesper;

    2014-01-01

    Structural colors are optical phenomena of physical origin, where microscale and nanoscale structures determine the reflected spectrum of light. Artificial structural colors have been realized within recent years. However, multilayer structures require substantial fabrication. Instead we consider...

  1. Ask a Scientist: What is Color Blindness?

    Medline Plus

    Full Text Available ... Sheldon Miller answers questions about color blindness, whether it can be treated, and how people become color ... I’m sleeping? Click to Watch What does it mean to be nearsighted or farsighted? Click to ...

  2. Spectral Test Instrument for Color Vision Measurement

    Institute of Scientific and Technical Information of China (English)

    Balázs Vince Nagy; Gy(o)rgy (A)brahám

    2005-01-01

    Common displays such as CRT or LCD screens have limited capabilities in displaying most color spectra correctly. The main disadvantage of these devices is that they work with three primaries and the colors displayed are the mixture of these three colours. Consequently these devices can be confusing in testing human color identification, because the spectral distribution of the colors displayed is the combined spectrum of the three primaries. We have developed a new instrument for spectrally correct color vision measurement. This instrument uses light emitting diodes (LEDs) and is capable of producing all spectra of perceivable colors, thus with appropriate test methods this instrument can be a reliable and useful tool in testing human color vision and in verifying color vision correction.

  3. Adaptive Color Mapping for NAO Robot Using Neural Network

    Directory of Open Access Journals (Sweden)

    Vahid Rahmani

    Full Text Available While playing soccer, the main task of the robot vision system is identifying and tracking objects such as ball, goals, teammate robots and opponent robots. The basis of many object identification methods, particularly those in soccer robots and RoboCup e ...

  4. DERIVATIONS AND EXTENSIONS OF LIE COLOR ALGEBRA

    Institute of Scientific and Technical Information of China (English)

    Zhang Qingcheng; Zhang Yongzheng

    2008-01-01

    In this article, the authors obtain some results concerning derivations of fi-nitely generated Lie color algebras and discuss the relation between skew derivation space SkDer(L) and central extension H2(L, F) on some Lie color algebras. Meanwhile, they generalize the notion of double extension to quadratic Lie color algebras, a sufficient con-dition for a quadratic Lie color algebra to be a double extension and further properties are given.

  5. Spatiochromatic Context Modeling for Color Saliency Analysis.

    Science.gov (United States)

    Zhang, Jun; Wang, Meng; Zhang, Shengping; Li, Xuelong; Wu, Xindong

    2016-06-01

    Visual saliency is one of the most noteworthy perceptual abilities of human vision. Recent progress in cognitive psychology suggests that: 1) visual saliency analysis is mainly completed by the bottom-up mechanism consisting of feedforward low-level processing in primary visual cortex (area V1) and 2) color interacts with spatial cues and is influenced by the neighborhood context, and thus it plays an important role in a visual saliency analysis. From a computational perspective, the most existing saliency modeling approaches exploit multiple independent visual cues, irrespective of their interactions (or are not computed explicitly), and ignore contextual influences induced by neighboring colors. In addition, the use of color is often underestimated in the visual saliency analysis. In this paper, we propose a simple yet effective color saliency model that considers color as the only visual cue and mimics the color processing in V1. Our approach uses region-/boundary-defined color features with spatiochromatic filtering by considering local color-orientation interactions, therefore captures homogeneous color elements, subtle textures within the object and the overall salient object from the color image. To account for color contextual influences, we present a divisive normalization method for chromatic stimuli through the pooling of contrary/complementary color units. We further define a color perceptual metric over the entire scene to produce saliency maps for color regions and color boundaries individually. These maps are finally globally integrated into a one single saliency map. The final saliency map is produced by Gaussian blurring for robustness. We evaluate the proposed method on both synthetic stimuli and several benchmark saliency data sets from the visual saliency analysis to salient object detection. The experimental results demonstrate that the use of color as a unique visual cue achieves competitive results on par with or better than 12 state

  6. Film Recording of Digital Color Images

    Science.gov (United States)

    1975-05-28

    physiological evidence indicating that the retina contains three kinds of color receptors. In fact, various kinds of color blindness have been...fundamental sensitivites of the eye. Fortunately, estimates of the s-(X) can be obtained by alternative methods, such as color blindness studies [4]. A...number of fundamental response curves have been proposed. One set which was deduced from color blindness data, and is in good agreement with more

  7. 7 CFR 51.2946 - Color chart.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color chart. 51.2946 Section 51.2946 Agriculture... Standards for Grades of Walnuts in the Shell General § 51.2946 Color chart. The color chart (USDA Walnut Color Chart) to which reference is made in §§ 51.2948, 51.2949, 51.2950, 51.2954, and...

  8. 7 CFR 29.3508 - Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color. 29.3508 Section 29.3508 Agriculture Regulations... Type 95) § 29.3508 Color. The third factor of a grade based on the relative hues, saturations or chromas, and color values common to the type....

  9. 7 CFR 29.2257 - Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color. 29.2257 Section 29.2257 Agriculture Regulations... INSPECTION Standards Official Standard Grades for Virginia Fire-Cured Tobacco (u.s. Type 21) § 29.2257 Color. The third factor of a grade based on the relative hues, saturation or chroma, and color values...

  10. 7 CFR 29.3010 - Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color. 29.3010 Section 29.3010 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Color. The third factor of a grade, based on the relative hues, saturations or chroma, and color...

  11. Color Charts, Esthetics, and Subjective Randomness

    Science.gov (United States)

    Sanderson, Yasmine B.

    2012-01-01

    Color charts, or grids of evenly spaced multicolored dots or squares, appear in the work of modern artists and designers. Often the artist/designer distributes the many colors in a way that could be described as "random," that is, without an obvious pattern. We conduct a statistical analysis of 125 "random-looking" art and design color charts and…

  12. 7 CFR 29.2507 - Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color. 29.2507 Section 29.2507 Agriculture Regulations...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2507 Color. The third factor of a grade based on the relative hues, saturation or chroma, and color values common to the type....

  13. 7 CFR 29.1005 - Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color. 29.1005 Section 29.1005 Agriculture Regulations... Type 92) § 29.1005 Color. The third factor of a grade based on the relative hues, saturations or chromas, and color values common to the type....

  14. 7 CFR 58.633 - Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Color. 58.633 Section 58.633 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections....633 Color. Coloring used for ice cream and related products shall be those certified by the U.S....

  15. Color Vision Deficits and Literacy Acquisition.

    Science.gov (United States)

    Hurley, Sandra Rollins

    1994-01-01

    Shows that color blindness, whether partial or total, inhibits literacy acquisition. Offers a case study of a third grader with impaired color vision. Presents a review of literature on the topic. Notes that people with color vision deficits are often unaware of the handicap. (RS)

  16. The Pragmatics of Color in Antara's Poetry

    Science.gov (United States)

    Btoosh, Mousa A.

    2014-01-01

    Perhaps rarely is there any piece of Pre-Islamic Arabic literature where color features more strongly and less naturally than in Antara's poetry. Therefore, the intended message of color in Antara's poetry is adequately understood inasmuch as the pragmatic implicatures of color are worked out. Evidence in literature explicitly attributes Antara's…

  17. 7 CFR 51.1860 - Color classification.

    Science.gov (United States)

    2010-01-01

    ... of green color may vary from light to dark; (2) Breakers. “Breakers” means that there is a definite... the aggregate, shows pink or red color; (5) Light red. “Light red” means that more than 60 percent of... color designations may be designated as “Mixed Color”. (c) For tolerances see § 51.1861. (d)...

  18. What It's Like to Be Color Blind

    Science.gov (United States)

    ... see colors properly. When your cones don't work properly, or you don't have the right combination, your brain doesn't get the right message about which colors you're seeing. To someone who's color blind, a green leaf might look tan or gray. ...

  19. 7 CFR 52.3760 - Color.

    Science.gov (United States)

    2010-01-01

    ... § 52.3760 Color. (a) General. The evaluation of color shall be determined within five minutes after the... green-ripe type olives. Off-color means dark brown, dark purple or black olives. (e) The USDA spinning... type—(i) Whole; pitted; halved. The olives or units have a practically uniform black or dark...

  20. Digital color restoration of old paintings.

    Science.gov (United States)

    Pappas, M; Pitas, I

    2000-01-01

    Physical and chemical changes can degrade the visual color appearance of old paintings. Five digital color restoration techniques, which can be used to simulate the original appearance of paintings, are presented. Although a small number of color samples is employed in the restoration procedure, simulation results indicate that good restoration quality can be attained.

  1. Color Vision Deficiencies in Children. United States.

    Science.gov (United States)

    National Center for Health Statistics (DHEW/PHS), Hyattsville, MD.

    Presented are prevalence data on color vision deficiencies (color blindness) in noninstitutionalized children, aged 6-11, in the United States, as estimated from the Health Examination Survey findings on a representative sample of over 7,400 children. Described are the two color vision tests used in the survey, the Ishihara Test for Color…

  2. Endangered Species of Florida Coloring Book.

    Science.gov (United States)

    King, Merlien W.

    This coloring book portrays endangered animal and plant species of Florida in their natural environment. Each picture is to be colored by the student. On the back of each page bearing the picture to be colored is a description of the animal or plant, its preferred habitat, and the reason the animal or plant is endangered. (RE)

  3. What It's Like to Be Color Blind

    Science.gov (United States)

    ... los dientes Video: Getting an X-ray What It's Like to Be Color Blind KidsHealth > For Kids > What It's Like to Be Color Blind Print A A ... blind. But some people really are color blind. It doesn't mean they can't see any ...

  4. Boltzmann Samplers for Colored Combinatorial Objects

    CERN Document Server

    Bodini, Olivier

    2009-01-01

    In this paper, we give a general framework for the Boltzmann generation of colored objects belonging to combinatorial constructible classes. We propose an intuitive notion called profiled objects which allows the sampling of size-colored objects (and also of k-colored objects) although the corresponding class cannot be described by an analytic ordinary generating function.

  5. 14 CFR 23.1397 - Color specifications.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Color specifications. 23.1397 Section 23.1397 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Color specifications. Each position light color must have the applicable International Commission...

  6. 7 CFR 29.2508 - Color intensity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color intensity. 29.2508 Section 29.2508 Agriculture...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2508 Color intensity. The varying degree of saturation or chroma. Color intensity as applied to tobacco describes the strength or weakness of a...

  7. 14 CFR 27.1397 - Color specifications.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Color specifications. 27.1397 Section 27... AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Lights § 27.1397 Color specifications. Each position light color must have the applicable International Commission on Illumination...

  8. 14 CFR 25.1397 - Color specifications.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Color specifications. 25.1397 Section 25... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Lights § 25.1397 Color specifications. Each position light color must have the applicable International Commission on Illumination...

  9. 14 CFR 29.1397 - Color specifications.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Color specifications. 29.1397 Section 29... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Lights § 29.1397 Color specifications. Each position light color must have the applicable International Commission on Illumination...

  10. 7 CFR 29.2258 - Color intensity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color intensity. 29.2258 Section 29.2258 Agriculture... INSPECTION Standards Official Standard Grades for Virginia Fire-Cured Tobacco (u.s. Type 21) § 29.2258 Color intensity. The varying degree of saturation or chroma. Color intensity as applied to tobacco describes...

  11. Dynamic simulation of color blindness for studying color vision requirements in practice

    NARCIS (Netherlands)

    Lucassen, M.P.; Alferdinck, J.W.A.M.

    2006-01-01

    We report on a dynamic simulation of defective color vision. Using an RGB video camera connected to a PC or laptop, the captured and displayed RGB colors are translated by our software into modified RGB values that simulate the color appearance of a person with a color deficiency. Usually, the simul

  12. Priming Letters by Colors: Evidence for the Bidirectionality of Grapheme-Color Synesthesia

    Science.gov (United States)

    Weiss, Peter H.; Kalckert, Andreas; Fink, Gereon R.

    2009-01-01

    In synesthesia, stimulation of one sensory modality leads to a percept in another nonstimulated modality, for example, graphemes trigger an additional color percept in grapheme-color synesthesia, which encompasses the variants letter-color and digit-color synesthesia. Until recently, it was assumed that synesthesia occurs strictly unidirectional:…

  13. Objective color harmony assessment for visible and infrared color fusion images of typical scenes

    Science.gov (United States)

    Gao, Shaoshu; Jin, Weiqi; Wang, Lingxue

    2012-11-01

    For visible and infrared color fusion images of three typical scenes, color harmony computational models are proposed to evaluate the color quality of fusion images without reference images. The models are established based on the color-combination harmony model and focus on the influence of the color characteristics of typical scenes and the color region sizes in the fusion image. For the influence of the color characteristics of typical scenes, color harmony adjusting factors for natural scene images (green plants, sea, and sky) are defined by measuring the similarity between image colors and corresponding memory colors, and that for town and building images are presented based on the optimum colorfulness range suited for a human. Simultaneously, considering the influence of color region sizes, the weight coefficients are established using areas of the color regions to optimize the color harmony model. Experimental results show that the proposed harmony models are consistent with human perception and that they are suitable to evaluate the color harmony for color fusion images of typical scenes.

  14. Vision Screening by Color Photography

    Science.gov (United States)

    Jayroe, R.; Richardson, J. R.; Kerr, J.; Hay, S.; Mcbride, R.

    1985-01-01

    Screening test developed for detecting a range of vision defects in eye, including common precursors to amblyopia. Test noninvasive, safe, and administered easily in field by operator with no medical training. Only minimal momentary cooperation of subject required: Thus, test shows promise for use with very young children. Test produces color-slide images of retinas of eyes under specially-controlled lighting conditions. Trained observer screens five children per minute.

  15. Mechanochromic Fibers with Structural Color.

    Science.gov (United States)

    Li, Houpu; Sun, Xuemei; Peng, Huisheng

    2015-12-21

    Responsive photonic crystals have been widely developed to realize tunable structural colors by manipulating the flow of light. Among them, mechanochromic photonic crystals attract increasing attention due to the easy operation, high safety and broad applications. Recently, mechanochromic photonic crystal fibers were proposed to satisfy the booming wearable smart textile market. In this Concept, the fundamental mechanism, fabrication, and recent progress on mechanochromic photonic crystals, especially in fiber shape, are summarized to represent a new direction in sensing and displaying.

  16. Anthocyanins as Functional Food Colors

    Science.gov (United States)

    Motohashi, Noboru; Sakagami, Hiroshi

    Anthocyanins, a proanthocyanidin-type of flavonoid, contain an abundance of functional phytochemicals and occur in fruits such as cranberry, blueberry, orange, apple and in vegetables such as tomato, sweet pepper, spinach, and radishes. Functional and essential diets have been ingested in daily life since the primitive era of history. When anthocyanins are coupled with some water-soluble sugar molecules, their color becomes red, yellow, violet, or blue. It is very intriguing that anthocyanins provide the colorful variety of pigments for pansies, petunias, plums, and other diverse flowers. Chlorophyll in various fruits and vegetables is the main green phyto-component, while anthocyanins are probably the most important visible plant pigments in the natural kingdom having specific colors. Anthocyanins have been clinically used in many folklore medicines worldwide. Anthocyanins could provide health benefits for age-related diseases as well as other diseases. Anthocyanins have higher antioxidant capacity against oxidative stress induced by excess reactive oxygen species (ROS) such as superoxide radicals, hydrogen peroxide, and thus the human body might be protected from oxidative injury by anthocyanins. On the basis of these facts, we review the synthesis of plant flavonoids and their ability to scavenge oxidants, inhibit or activate enzymes, and the safety of proanthocyanidins and anthocyanidins present in common foods.

  17. Towards a new urbarchitectonic coloration

    Directory of Open Access Journals (Sweden)

    Cekić Nikola

    2008-01-01

    Full Text Available The crisis in ecorurbarchitecture of modern times is reflected in the large number of superficially conceived villages and towns, houses, streets and plazas, lacking the artistic contents, as well as the coloration synchronized with the natural structures in the environment. Creators of the architecture failed to see the color as the fourth dimension, even though it was at hand. The failed to understand its role as a primarily multidisciplinary issue of awareness, culture, tradition, human customs, their ethnic and historical understanding of the artifact-nature relation, and its role as a corrective procedure to improve the living conditions in the habitations and its role in unifying of ecorurbarchitectonic values in the vision of art. The creators also failed to convince the future users to comprehend that village and city, different as they are, have noticeably drawn closer in terms of art. The aim of this paper is to pose the crucial questions concerning the new ecorurbarchitectonic coloration, which may improve the state of physical structures in space.

  18. Three-flavor color superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Malekzadeh, H.

    2007-12-15

    I investigate some of the inert phases in three-flavor, spin-zero color-superconducting quark matter: the CFL phase (the analogue of the B phase in superfluid {sup 3}He), the A and A{sup *} phases, and the 2SC and sSC phases. I compute the pressure of these phases with and without the neutrality condition. Without the neutrality condition, after the CFL phase the sSC phase is the dominant phase. However, including the neutrality condition, the CFL phase is again the energetically favored phase except for a small region of intermediate densities where the 2SC/A{sup *} phase is favored. It is shown that the 2SC phase is identical to the A{sup *} phase up to a color rotation. In addition, I calculate the self-energies and the spectral densities of longitudinal and transverse gluons at zero temperature in color-superconducting quark matter in the CFL phase. I find a collective excitation, a plasmon, at energies smaller than two times the gap parameter and momenta smaller than about eight times the gap. The dispersion relation of this mode exhibits a minimum at some nonzero value of momentum, indicating a van Hove singularity. (orig.)

  19. [Cosmetic colorants. Toxicology and regulation].

    Science.gov (United States)

    Platzek, T; Krätke, R; Klein, G; Schulz, C

    2005-01-01

    Some recent publications raised concern over a possible link between hair dye use and the incidence of bladder tumours in a Californian population. The Scientific Committee for Cosmetic Products and Non-Food Products intended for Consumers (SCCNFP) demanded the toxicological testing of all hair dyes used in Europe to exclude any risk. The EU commission initiated corresponding measures. Only safe hair dyes will be included on a positive list while all other hair dyes will be banned. The hair dye lawsone--the dyeing ingredient of henna--was evaluated by the SCCNFP as genotoxic but the BfR came to another conclusion. The regulation of both lawsone and henna remains an open question. Furthermore, some cosmetic colorants were critically discussed. The azo dyes CI 12150, CI 26100, CI 27290 and CI 20170 are allowed for use in cosmetics. On cleavage they form the carcinogenic aromatic amines o-anisidine, 4-aminoazobenzene and 2,4-xylidine, respectively. For three of these dyes the cleavage by human skin bacteria in vitro to the respective arylamine was shown experimentally. Further problems may arise from colorants used for tattoos and permanent makeup. These products up to now are not subject to legislation and there are no regulatory stipulations with respect to health safety and purity for colorants used for these purposes.

  20. Optically tunable plasmonic color filters

    Science.gov (United States)

    Liu, Y. J.; Si, G. Y.; Leong, E. S. P.; Wang, B.; Danner, A. J.; Yuan, X. C.; Teng, J. H.

    2012-04-01

    We fabricated sub-wavelength patterned gold plasmonic nanostructures on a quartz substrate through the focused ion beam (FIB) technique. The perforated gold film demonstrated optical transmission peaks in the visible range, which therefore can be used as a plasmonic color filter. Furthermore, by integrating a layer of photoresponsive liquid crystals (LCs) with the gold nanostructure to form a hybrid system, we observed a red-shift of transmission peak wavelength. More importantly, the peak intensity can be further enhanced more than 10% in transmittance due to the refractive index match of the media on both sides of it. By optically pumping the hybrid system using a UV light, nematic-isotropic phase transition of the LCs was achieved, thus changing the effective refractive index experienced by the impinging light. Due to the refractive index change, the transmission peak intensity was modulated accordingly. As a result, an optically tunable plasmonic color filter was achieved. This kind of color filters could be potentially applied to many applications, such as complementary metal-oxide-semiconductor (CMOS) image sensors, liquid crystal display devices, light emitting diodes, etc.

  1. Color visualization of cyclic magnitudes

    Science.gov (United States)

    Restrepo, Alfredo; Estupiñán, Viviana

    2014-02-01

    We exploit the perceptual, circular ordering of the hues in a technique for the visualization of cyclic variables. The hue is thus meaningfully used for the indication of variables such as the azimuth and the units of the measurement of time. The cyclic (or circular) variables may be both of the continuous type or the discrete type; among the first there is azimuth and among the last you find the musical notes and the days of the week. A correspondence between the values of a cyclic variable and the chromatic hues, where the natural circular ordering of the variable is respected, is called a color code for the variable. We base such a choice of hues on an assignment of of the unique hues red, yellow, green and blue, or one of the 8 even permutations of this ordered list, to 4 cardinal values of the cyclic variable, suitably ordered; color codes based on only 3 cardinal points are also possible. Color codes, being intuitive, are easy to remember. A possible low accuracy when reading instruments that use this technique is compensated by fast, ludic and intuitive readings; also, the use of a referential frame makes readings precise. An achromatic version of the technique, that can be used by dichromatic people, is proposed.

  2. The influence of surface color information and color knowledge information in object recognition.

    Science.gov (United States)

    Bramão, Inês; Faísca, Luís; Petersson, Karl Magnus; Reis, Alexandra

    2010-01-01

    In order to clarify whether the influence of color knowledge information in object recognition depends on the presence of the appropriate surface color, we designed a name-object verification task. The relationship between color and shape information provided by the name and by the object photo was manipulated in order to assess color interference independently of shape interference. We tested three different versions for each object: typically colored, black and white, and nontypically colored. The response times on the nonmatching trials were used to measure the interference between the name and the photo. We predicted that the more similar the name and the photo are, the longer it would take to respond. Overall, the color similarity effect disappeared in the black-and-white and nontypical color conditions, suggesting that the influence of color knowledge on object recognition depends on the presence of the appropriate surface color information.

  3. [Study of spectrum drifting of primary colors and its impact on color rendering properties].

    Science.gov (United States)

    Cui, Xiao-yan; Zhang, Xiao-dong

    2012-08-01

    LEDs are currently used widely to display text, graphics and images in large screens. With red, green and blue LEDs as three primary colors, color rendition will be realized through color mixing. However, LEDs' spectrum will produce drifts with the changes in the temperature environment. With the changes in the driving current simulating changes in the temperature, the three primary color LEDs' spectral drifts were tested, and the drift characteristics of the three primary colors were obtained respectively. Based on the typical characteristics of the LEDs and the differences between LEDs with different colors in composition and molecular structure, the paper analyzed the reason for the spectrum drifts and the drift characteristics of different color LEDs, and proposed the equations of spectrum drifts. Putting the experimental data into the spectrum drift equations, the paper analyzed the impacts of primary colors on the mixed color, pointed out a way to reduce the chromatic aberration, and provided the theory for engineering application of color LEDs.

  4. Color management understanding and using ICC profiles

    CERN Document Server

    Green, Phil

    2010-01-01

    Color Management serves as a comprehensive guide to the implementation of the ICC (International Color Consortium) profile specification, widely used for maintaining color fidelity across multi-media imaging devices and software. The book draws together many of the White Papers produced by the ICC to promote the use of color management and disseminate good practice; the ICC specification has become widely accepted within the color industry, and these papers have been updated, expanded and edited for this collection. Other chapters comprise material that will go on to form future ICC Whi

  5. Perceptual transparency in neon color spreading displays.

    Science.gov (United States)

    Ekroll, Vebjørn; Faul, Franz

    2002-08-01

    In neon color spreading displays, both a color illusion and perceptual transparency can be seen. In this study, we investigated the color conditions for the perception of transparency in such displays. It was found that the data are very well accounted for by a generalization of Metelli's (1970) episcotister model of balanced perceptual transparency to tristimulus values. This additive model correctly predicted which combinations of colors would lead to optimal impressions of transparency. Color combinations deviating slightly from the additive model also looked transparent, but less convincingly so.

  6. Harmonious colors: from alchemy to science

    Science.gov (United States)

    Beretta, Giordano B.; Moroney, Nathan M.

    2012-01-01

    There is a very long tradition in designing color palettes for various applications, going back to at least the Upanishad. Although color palettes have been influenced by the available colorants, starting with the advent of aniline dyes in the late 1850s there have been few physical limits on the choice of individual colors. This abundance of choices exacerbates the problem of limiting the number of colors in a palette, i.e., in keeping them into a manageable quantity. For example, it is not practical for a car company to offer each model in hundreds of colors. Instead, for each model year a small number of color palettes is offered, each containing the colors for the body, trim, interior, etc. Another example is the fashion industry, where in addition to solid colors there are also patterns, leading to a huge variety of combinations that would be impossible to stock. The traditional solution is that of "color forecasting." Color consultants assess the sentiment or affective state of a target customer class and compare it with new colorants offered by the industry. They assemble a limited color palette, name the colors according to the sentiment, and publish their result. Textile manufacturers will produce fabrics in these colors and fashion designers will design clothes, accessories, and furniture based on these fabrics. Eventually, the media will communicate these forecasts to the consumers, who will be admired by their cohorts when they choose colors from the forecast palette, which by then is widely diffused. The color forecasting business is very labor intensive and difficult, thus for years computer engineers have tried to come up with algorithms to design harmonious color palettes, alas with little commercial success. For example, Johannes Itten's color theory has been implemented many times, but despite Itten's success in the Bauhaus artifacts, the computer tools have been of little utility. Indeed, contrary to the auditory sense, there is no known

  7. Aluminum plasmonic metamaterials for structural color printing.

    Science.gov (United States)

    Cheng, Fei; Gao, Jie; Stan, Liliana; Rosenmann, Daniel; Czaplewski, David; Yang, Xiaodong

    2015-06-01

    We report a structural color printing platform based on aluminum plasmonic metamaterials supporting near perfect light absorption and narrow-band spectral response tunable across the visible spectrum to realize high-resolution, angle-insensitive color printing with high color purity and saturation. Additionally, the fabricated metamaterials can be protected by a transparent polymer thin layer for ambient use with further improved color performance. The demonstrated structural color printing with aluminum plasmonic metamaterials offers great potential for relevant applications such as security marking and information storage.

  8. Dichromatic confusion lines and color vision models.

    Science.gov (United States)

    Fry, G A

    1986-12-01

    An attempt has been made to explain how dichromatic confusion lines can be used in building a model for color vision. In the König color vision model the fundamental colors are located on the mixture diagram at the copunctal points for protanopes, deuteranopes, and tritanopes. In Fry's model the copunctal points fall on the alychne and cannot represent the fundamental colors. On a constant luminance diagram the confusion lines for the different dichromats are sets of parallel lines. This arrangement of the confusion lines can be explained in terms of a zone theory of color vision.

  9. Evaluation of the Artificial Neural Network for Color Discrimination : Discrimination of Non-learned Colors

    OpenAIRE

    Tayagaki, Yasuko; Sekiya, Satoko; Sekine, Seishi; Ohkawa, Masashi

    2004-01-01

    Our research purpose is to build an artificial neural network with an excellent color discrimination capability like human being on a computer. In this study, we built the network, which was trained to learn 10 colors with different hues in the Munsell color system. Then, we examined the response of the trained network when the network was interrogated about 10 non-learned colors. The network showed a good color discrimination capability, close to that of human being.

  10. When colors backfire: The impact of color cues on moral judgment

    OpenAIRE

    De Bock, Tine; Pandelaere, Mario; Van Kenhove, Patrick

    2013-01-01

    This article investigates if and how the valence of color cues affects moral acceptability of (un)desirable consumer behaviors. Study 1 uses colors with definite differences in terms of valence, namely, red and green. Study 2 applies an evaluative conditioning paradigm to endow initially neutral colors with negative versus positive valences. We find an ironic color effect: undesirable behaviors become more acceptable when presented with negatively valenced colors. In general, respondents find...

  11. Colors of Ellipticals from GALEX to Spitzer

    CERN Document Server

    Schombert, J

    2016-01-01

    Multi-color photometry is presented for a large sample of local ellipticals selected by morphology and isolation. The sample uses data from GALEX, SDSS, 2MASS and Spitzer to cover the filters NUV, ugri, JHK and 3.6mum. Various two-color diagrams, using the half-light aperture defined in the 2MASS J filter, are very coherent from color to color, meaning that galaxies defined to be red in one color are always red in other colors. Comparison to globular cluster colors demonstrates that ellipticals are *not* composed of a single age, single metallicity (e.g., [Fe/H]) stellar population, but require a multi-metallicity model using a chemical enrichment scenario. Such a model is sufficient to explain two-color diagrams and the color-magnitude relations for all colors using only metallicity as a variable on a solely 12 Gyrs stellar population with no evidence of stars younger than 10 Gyrs. The [Fe/H] values that match galaxy colors range from -0.5 to +0.4, much higher (and older) than population characteristics dedu...

  12. k-fold coloring of planar graphs

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A k-fold n-coloring of G is a mapping φ: V (G) → Zk(n) where Zk(n) is the collection of all ksubsets of {1,2,...,n} such that φ(u) ∩φ(v) = φ if uv ∈ E(G).If G has a k-fold n-coloring,i.e.,G is k-fold n-colorable.Let the smallest integer n such that G is k-fold n-colorable be the k-th chromatic number,denoted by χk(G).In this paper,we show that any outerplanar graph is k-fold 2k-colorable or k-fold χk(C*)-colorable,where C* is a shortest odd cycle of G.Moreover,we investigate that every planar graph with odd girth at least 10k-9(k 3) can be k-fold (2k + 1)-colorable.

  13. Frequency correlates in grapheme-color synaesthesia.

    Science.gov (United States)

    Beeli, Gian; Esslen, Michaela; Jäncke, Lutz

    2007-09-01

    Individuals with synaesthesia experience certain stimuli in more than one sensory modality. Most common is the linkage of letters and digits (graphemes) to colors. Whereas synaesthesia might be partly genetically determined, the linkages to specific colors are assumed to be learned. We present a systematic statistical analysis of synaesthetic color perception based on subjects' reproduction of individual colors for each grapheme, instead of simple verbal categorizations. The statistical analysis revealed that the color perceptions, measured with the HSL (hue, saturation, and luminance) scale, varied systematically among the different digits and letters. The frequencies of the digits and letters (in the German language) partly explained these systematic variations. However, digit frequency was more strongly related to color perception in the synaesthetes than was letter frequency. The results for digit and letter frequency indicate that experience with graphemes may shape synaesthetic color perception.

  14. Colored Range Searching in Linear Space

    DEFF Research Database (Denmark)

    Grossi, Roberto; Vind, Søren Juhl

    2014-01-01

    In colored range searching, we are given a set of n colored points in d ≥ 2 dimensions to store, and want to support orthogonal range queries taking colors into account. In the colored range counting problem, a query must report the number of distinct colors found in the query range, while...... an answer to the colored range reporting problem must report the distinct colors in the query range. We give the first linear space data structure for both problems in two dimensions (d = 2) with o(n) worst case query time. We also give the first data structure obtaining almost-linear space usage and o......(n) worst case query time for points in d > 2 dimensions. Finally, we present the first dynamic solution to both counting and reporting with o(n) query time for d ≥ 2 and d ≥ 3 dimensions, respectively....

  15. Number of discernible colors for color-deficient observers estimated from the MacAdam limits.

    Science.gov (United States)

    Perales, Esther; Martínez-Verdú, Francisco Miguel; Linhares, João Manuel Maciel; Nascimento, Sérgio Miguel Cardoso

    2010-10-01

    We estimated the number of colors perceived by color normal and color-deficient observers when looking at the theoretic limits of object-color stimuli. These limits, the optimal color stimuli, were computed for a color normal observer and CIE standard illuminant D65, and the resultant colors were expressed in the CIELAB and DIN99d color spaces. The corresponding color volumes for abnormal color vision were computed using models simulating for normal trichromatic observers the appearance for dichromats and anomalous trichomats. The number of colors perceived in each case was then computed from the color volumes enclosed by the optimal colors also known as MacAdam limits. It was estimated that dichromats perceive less than 1% of the colors perceived by normal trichromats and that anomalous trichromats perceive 50%-60% for anomalies in the medium-wavelength-sensitive and 60%-70% for anomalies in the long-wavelength-sensitive cones. Complementary estimates obtained similarly for the spectral locus of monochromatic stimuli suggest less impairment for color-deficient observers, a fact that is explained by the two-dimensional nature of the locus.

  16. A quantitative theory of human color choices.

    Science.gov (United States)

    Komarova, Natalia L; Jameson, Kimberly A

    2013-01-01

    The system for colorimetry adopted by the Commission Internationale de l'Eclairage (CIE) in 1931, along with its subsequent improvements, represents a family of light mixture models that has served well for many decades for stimulus specification and reproduction when highly controlled color standards are important. Still, with regard to color appearance many perceptual and cognitive factors are known to contribute to color similarity, and, in general, to all cognitive judgments of color. Using experimentally obtained odd-one-out triad similarity judgments from 52 observers, we demonstrate that CIE-based models can explain a good portion (but not all) of the color similarity data. Color difference quantified by CIELAB ΔE explained behavior at levels of 81% (across all colors), 79% (across red colors), and 66% (across blue colors). We show that the unexplained variation cannot be ascribed to inter- or intra-individual variations among the observers, and points to the presence of additional factors shared by the majority of responders. Based on this, we create a quantitative model of a lexicographic semiorder type, which shows how different perceptual and cognitive influences can trade-off when making color similarity judgments. We show that by incorporating additional influences related to categorical and lightness and saturation factors, the model explains more of the triad similarity behavior, namely, 91% (all colors), 90% (reds), and 87% (blues). We conclude that distance in a CIE model is but the first of several layers in a hierarchy of higher-order cognitive influences that shape color triad choices. We further discuss additional mitigating influences outside the scope of CIE modeling, which can be incorporated in this framework, including well-known influences from language, stimulus set effects, and color preference bias. We also discuss universal and cultural aspects of the model as well as non-uniformity of the color space with respect to different

  17. Color quantization and processing by Fibonacci lattices.

    Science.gov (United States)

    Mojsilovic, A; Soljanin, E

    2001-01-01

    Color quantization is sampling of three-dimensional (3-D) color spaces (such as RGB or Lab) which results in a discrete subset of colors known as a color codebook or palette. It is extensively used for display, transfer, and storage of natural images in Internet-based applications, computer graphics, and animation. We propose a sampling scheme which provides a uniform quantization of the Lab space. The idea is based on several results from number theory and phyllotaxy. The sampling algorithm is very much systematic and allows easy design of universal (image-independent) color codebooks for a given set of parameters. The codebook structure allows fast quantization and ordered dither of color images. The display quality of images quantized by the proposed color codebooks is comparable with that of image-dependent quantizers. Most importantly, the quantized images are more amenable to the type of processing used for grayscale ones. Methods for processing grayscale images cannot be simply extended to color images because they rely on the fact that each gray-level is described by a single number and the fact that a relation of full order can be easily established on the set of those numbers. Color spaces (such as RGB or Lab) are, on the other hand, 3-D. The proposed color quantization, i.e., color space sampling and numbering of sampled points, makes methods for processing grayscale images extendible to color images. We illustrate possible processing of color images by first introducing the basic average and difference operations and then implementing edge detection and compression of color quantized images.

  18. Color Space and Its Divisions: Color Order from Antiquity to the Present

    Science.gov (United States)

    Kuehni, Rolf G.

    2003-03-01

    It has been postulated that humans can differentiate between millions of gradations in color. Not surprisingly, no completely adequate, detailed catalog of colors has yet been devised, however the quest to understand, record, and depict color is as old as the quest to understand the fundamentals of the physical world and the nature of human consciousness. Rolf Kuehni's Color Space and Its Divisions: Color Order from Antiquity to the Present represents an ambitious and unprecedented history of man's inquiry into color order, focusing on the practical applications of the most contemporary developments in the field. Kuehni devotes much of his study to geometric, three-dimensional arrangements of color experiences, a type of system developed only in the mid-nineteenth century. Color spaces are of particular interest for color quality-control purposes in the manufacturing and graphics industries. The author analyzes three major color order systems in detail: Munsell, OSA-UCS, and NCS. He presents historical and current information on color space developments in color vision, psychology, psychophysics, and color technology. Chapter topics include: A historical account of color order systems Fundamentals of psychophysics and the relationship between stimuli and experience Results of perceptual scaling of colors according to attributes History of the development of mathematical color space and difference formulas Analysis of the agreements and discrepancies in psychophysical data describing color differences An experimental plan for the reliable, replicated perceptual data necessary to make progress in the field Experts in academia and industry, neuroscientists, designers, art historians, and anyone interested in the nature of color will find Color Space and Its Divisions to be the authoritative reference in its field.

  19. 7 CFR 28.442 - Middling Yellow Stained Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Middling Yellow Stained Color. 28.442 Section 28.442... Stained Color. Middling Yellow Stained Color is American Upland cotton which in color is deeper than Middling Tinged Color. below color grade cotton...

  20. Study on the Pigments of the Colored Cotton

    Institute of Scientific and Technical Information of China (English)

    GU Zhao-wen; SHI Song-cun

    2004-01-01

    The ecological characteristics and fiber structure of the colored cotton were introduced briefly. The color changing mechanisms of the pigments extracted from colored cottons and some plants were discussed with the results of different experiments, which could offer an academic reference for the color fixations of the colored cotton textile produces and promote the development of the natural colored cotton industry.

  1. The Color of Safety: Ingroup Associated Colors make Beer Safer

    Science.gov (United States)

    Loersch, Chris; Bartholow, Bruce D.

    2010-01-01

    Individuals display high levels of trust and express feelings of safety when interacting with social ingroup members. Here, we investigated whether cues related to ingroup membership would change perceptions of the safety of alcohol. Participants were exposed to images of beer in either a standard can or a can featuring the colors of their university (i.e., ‘fan cans’). We hypothesized that exposure to fan cans would change perceptions of the risks of beer drinking. Results showed that participants exposed to fan cans rated beer consumption as less dangerous (Experiment 1), were more likely to automatically activate safety-related mental content after unconscious perception of beer cues (Experiment 2), and viewed their ingroup’s party practices as less dangerous (Experiment 3). These results provide evidence that ingroup-associated colors can serve as a safety cue for alcohol, which may in theory perpetuate alcohol-related risk-taking, already a cause for concern on college and university campuses. PMID:21499547

  2. Nonlinear color-image decomposition for image processing of a digital color camera

    Science.gov (United States)

    Saito, Takahiro; Aizawa, Haruya; Yamada, Daisuke; Komatsu, Takashi

    2009-01-01

    This paper extends the BV (Bounded Variation) - G and/or the BV-L1 variational nonlinear image-decomposition approaches, which are considered to be useful for image processing of a digital color camera, to genuine color-image decomposition approaches. For utilizing inter-channel color cross-correlations, this paper first introduces TV (Total Variation) norms of color differences and TV norms of color sums into the BV-G and/or BV-L1 energy functionals, and then derives denoising-type decomposition-algorithms with an over-complete wavelet transform, through applying the Besov-norm approximation to the variational problems. Our methods decompose a noisy color image without producing undesirable low-frequency colored artifacts in its separated BV-component, and they achieve desirable high-quality color-image decomposition, which is very robust against colored random noise.

  3. Synesthesia induced colors do not bias attention in the same manner as physical colors do

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik; Ásgeirsson, Árni Gunnar

    2015-01-01

    display. Retaining color information in memory biases attention towards that specific color in visual search, apparent by response time costs when a matching distractor is present, but a benefit when the target matches the retained color. We investigated whether a synesthetic color is automatically...... represented in visual memory of observers with color-grapheme synesthesia, and consequently biases attention towards the synesthesia congruent stimuli. A group of synesthetes performed a memory task combined with a visual search for colored Landolt squares to explore this question. Each trial started......Grapheme-color synesthesia affects visual cognition in significant ways. The congruence or incongruence of physical stimuli with synesthetic color affects how quickly and accurately synesthetes respond to stimuli, and the induced color experience may help them memorize achromatic material...

  4. Development of an XYZ Digital Camera with Embedded Color Calibration System for Accurate Color Acquisition

    Science.gov (United States)

    Kretkowski, Maciej; Jablonski, Ryszard; Shimodaira, Yoshifumi

    Acquisition of accurate colors is important in the modern era of widespread exchange of electronic multimedia. The variety of device-dependent color spaces causes troubles with accurate color reproduction. In this paper we present the outlines of accomplished digital camera system with device-independent output formed from tristimulus XYZ values. The outstanding accuracy and fidelity of acquired color is achieved in our system by employing an embedded color calibration system based on emissive device generating reference calibration colors with user-defined spectral distribution and chromaticity coordinates. The system was tested by calibrating the camera using 24 reference colors spectrally reproduced from 24 color patches of the Macbeth Chart. The average color difference (CIEDE2000) has been found to be ΔE =0.83, which is an outstanding result compared to commercially available digital cameras.

  5. 3D histogram visualization in different color spaces with application in color clustering classification

    Science.gov (United States)

    Marcu, Gabriel G.; Abe, Satoshi

    1995-04-01

    The paper presents a dynamically visualization procedure for 3D histogram of color images. The procedure runs for RGB, YMC, HSV, HSL device dependent color spaces and for Lab, Luv device independent color spaces and it is easily extendable to other color spaces if the analytical form of color transformations is available. Each histogram value is represented in the color space as a colored ball, in a position corresponding to the place of color in the color space. The paper presents the procedures for nonlinear ball normalization, ordering of drawing, space edges drawing, translation, scaling and rotation of the histogram. The 3D histogram visualization procedure can be used in different applications described in the second part of the paper. It enables to get a clear representation of the range of colors of one image, to derive and compare the efficiency of different clusterization procedures for color classification, to display comparatively the gamut of different color devices, to select the color space for an optimal mapping procedure of the outside gamut colors for minimizing the hue error, to detect bad-alignment in RGB planes for a sequential process.

  6. Simple perceptual color space for color specification and real-time processing

    Science.gov (United States)

    Kotsarenko, Yuriy; Ramos, Fernando

    2011-08-01

    In this work an alternative color space is described that defines the color elements in terms of approximated brightness, hue and saturation, similar to other color spaces commonly used in computer applications. The classical color spaces such as HSL and HSV in the form that is widely used are made for convenience, and do not model colors based on human perception. Other classical color spaces such as CIELAB, DIN99 and even more recent CIECAM-based color spaces are too cumbersome and difficult to work with. The proposed alternative, on the other hand, is simple to work with and has its "lightness" component tuned up to represent the perceived brightness closer to the reality. It is based on how luma is calculated in color spaces such as YUV and YIQ among others, but instead of using constant coefficients, it uses Euclidean distance formula with weighting coefficients. Several experiments are described that illustrate the proposed color space visualized in 3D and compared to other color spaces in perceptual terms and performance benchmarks. This is aided by a novel technique that allows normalizing the chroma of existing color spaces within a fixed interval. The experiments show that the proposed color space is a viable alternative for applications that already use HSV and HSL. A practical application is described, where the color space is used for 3D illumination with specular reflections running on dedicated graphics processor unit using shaders. This resolves visual defects present in the classical approaches that use RGB color space.

  7. How redundant are redundant color adjectives? An efficiency-based analysis of color overspecification

    Directory of Open Access Journals (Sweden)

    Paula eRubio-Fernández

    2016-02-01

    Full Text Available Color adjectives tend to be used redundantly in referential communication. I propose that redundant color adjectives are often intended to exploit a color contrast in the visual context and hence facilitate object identification, despite not being necessary to establish unique reference. Two language-production experiments investigated two types of factors that may affect the use of redundant color adjectives: factors related to the efficiency of color in the visual context and factors related to the semantic category of the noun. The results of Experiment 1 confirmed that people produce redundant color adjectives when color may facilitate object recognition; e.g., they do so more often in polychrome displays than in monochrome displays, and more often in English (pre-nominal position than in Spanish (post-nominal position. Redundant color adjectives are also used when color is a central property of the object category; e.g., people referred to the color of clothes more often than to the color of geometrical figures (Experiment 1, and they overspecified atypical colors more often than variable and stereotypical colors (Experiment 2. These results are relevant for pragmatic models of referential communication based on Gricean pragmatics and informativeness. An alternative analysis is proposed, which focuses on the efficiency and pertinence of color in a given referential situation.

  8. Global Color Mosaic of Triton

    Science.gov (United States)

    1980-01-01

    Global color mosaic of Triton, taken in 1989 by Voyager 2 during its flyby of the Neptune system. Color was synthesized by combining high- resolution images taken through orange, violet, and ultraviolet filters; these images were displayed as red, green, and blue images and combined to create this color version. With a radius of 1,350 (839 mi), about 22% smaller than Earth's moon, Triton is by far the largest satellite of Neptune. It is one of only three objects in the Solar System known to have a nitrogen-dominated atmosphere (the others are Earth and Saturn's giant moon, Titan). Triton has the coldest surface known anywhere in the Solar System (38 K, about -391 degrees Farenheit); it is so cold that most of Triton's nitrogen is condensed as frost, making it the only satellite in the Solar System known to have a surface made mainly of nitrogen ice. The pinkish deposits constitute a vast south polar cap believed to contain methane ice, which would have reacted under sunlight to form pink or red compounds. The dark streaks overlying these pink ices are believed to be an icy and perhaps carbonaceous dust deposited from huge geyser-like plumes, some of which were found to be active during the Voyager 2 flyby. The bluish-green band visible in this image extends all the way around Triton near the equator; it may consist of relatively fresh nitrogen frost deposits. The greenish areas include what is called the cataloupe terrain, whose origin is unknown, and a set of 'cryovolcanic' landscapes apparently produced by icy-cold liquids (now frozen) erupted from Triton's interior.

  9. Watermarking spot colors in packaging

    Science.gov (United States)

    Reed, Alastair; Filler, TomáÅ.¡; Falkenstern, Kristyn; Bai, Yang

    2015-03-01

    In January 2014, Digimarc announced Digimarc® Barcode for the packaging industry to improve the check-out efficiency and customer experience for retailers. Digimarc Barcode is a machine readable code that carries the same information as a traditional Universal Product Code (UPC) and is introduced by adding a robust digital watermark to the package design. It is imperceptible to the human eye but can be read by a modern barcode scanner at the Point of Sale (POS) station. Compared to a traditional linear barcode, Digimarc Barcode covers the whole package with minimal impact on the graphic design. This significantly improves the Items per Minute (IPM) metric, which retailers use to track the checkout efficiency since it closely relates to their profitability. Increasing IPM by a few percent could lead to potential savings of millions of dollars for retailers, giving them a strong incentive to add the Digimarc Barcode to their packages. Testing performed by Digimarc showed increases in IPM of at least 33% using the Digimarc Barcode, compared to using a traditional barcode. A method of watermarking print ready image data used in the commercial packaging industry is described. A significant proportion of packages are printed using spot colors, therefore spot colors needs to be supported by an embedder for Digimarc Barcode. Digimarc Barcode supports the PANTONE spot color system, which is commonly used in the packaging industry. The Digimarc Barcode embedder allows a user to insert the UPC code in an image while minimizing perceptibility to the Human Visual System (HVS). The Digimarc Barcode is inserted in the printing ink domain, using an Adobe Photoshop plug-in as the last step before printing. Since Photoshop is an industry standard widely used by pre-press shops in the packaging industry, a Digimarc Barcode can be easily inserted and proofed.

  10. Color Vision Defects in School Going Children

    Directory of Open Access Journals (Sweden)

    R K Shrestha

    2010-12-01

    Full Text Available Introduction: Color Vision defect can be observed in various diseases of optic nerve and retina and also a significant number of people suffer from the inherited condition of red and green color defect. Methods: A cross-sectional descritptive study was designed with purposive sampling of students from various schools of Kathmandu Valley. All children were subjected to color vision evaluation using Ishihara Isochromatic color plates along with other examination to rule out any other causes of color deficiency. Results: A total of 2001 students were examined, 1050 male students and 951 females with mean age of 10.35 (±2.75 and 10.54 (±2.72 respectively. Among the total students examined, 2.1% had some form of color vision defects. Of the male population , 3.9% had color vision defects while none of the female was found with the deficiency. Conclusions: The prelevance of color vision defect in Nepal is significant and comparable with the prelevance quoted in the studies from different countries. Keywords:color vision; congenital red green color effect; Nepal; prevalence.

  11. Full-color holographic 3D printer

    Science.gov (United States)

    Takano, Masami; Shigeta, Hiroaki; Nishihara, Takashi; Yamaguchi, Masahiro; Takahashi, Susumu; Ohyama, Nagaaki; Kobayashi, Akihiko; Iwata, Fujio

    2003-05-01

    A holographic 3D printer is a system that produces a direct hologram with full-parallax information using the 3-dimensional data of a subject from a computer. In this paper, we present a proposal for the reproduction of full-color images with the holographic 3D printer. In order to realize the 3-dimensional color image, we selected the 3 laser wavelength colors of red (λ=633nm), green (λ=533nm), and blue (λ=442nm), and we built a one-step optical system using a projection system and a liquid crystal display. The 3-dimensional color image is obtained by synthesizing in a 2D array the multiple exposure with these 3 wavelengths made on each 250mm elementary hologram, and moving recording medium on a x-y stage. For the natural color reproduction in the holographic 3D printer, we take the approach of the digital processing technique based on the color management technology. The matching between the input and output colors is performed by investigating first, the relation between the gray level transmittance of the LCD and the diffraction efficiency of the hologram and second, by measuring the color displayed by the hologram to establish a correlation. In our first experimental results a non-linear functional relation for single and multiple exposure of the three components were found. These results are the first step in the realization of a natural color 3D image produced by the holographic color 3D printer.

  12. Statistical pressure snakes based on color images.

    Energy Technology Data Exchange (ETDEWEB)

    Schaub, Hanspeter [ORION International Technologies, Albuquerque, NM

    2004-05-01

    The traditional mono-color statistical pressure snake was modified to function on a color image with target errors defined in HSV color space. Large variations in target lighting and shading are permitted if the target color is only specified in terms of hue. This method works well with custom targets where the target is surrounded by a color of a very different hue. A significant robustness increase is achieved in the computer vision capability to track a specific target in an unstructured, outdoor environment. By specifying the target color to contain hue, saturation and intensity values, it is possible to establish a reasonably robust method to track general image features of a single color. This method is convenient to allow the operator to select arbitrary targets, or sections of a target, which have a common color. Further, a modification to the standard pixel averaging routine is introduced which allows the target to be specified not only in terms of a single color, but also using a list of colors. These algorithms were tested and verified by using a web camera attached to a personal computer.

  13. Theoretical research on color indirect effects

    Science.gov (United States)

    Liu, T. C.; Liao, Changjun; Liu, Songhao

    1995-05-01

    Color indirect effects (CIE) means the physiological and psychological effects of color resulting from color vision. In this paper, we study CIE from the viewpoints of the integrated western and Chinese traditional medicine and the time quantum theory established by C. Y. Liu et al., respectively, and then put forward the color-automatic-nervous-subsystem model that could color excites parasympathetic subsystem and hot color excites sympathetic subsystem. Our theory is in agreement with modern color vision theory, and moreover, it leads to the resolution of the conflict between the color code theory and the time code theory oncolor vision. For the latitude phenomena on athlete stars number and the average lifespan, we also discuss the possibility of UV vision. The applications of our theory lead to our succeeding in explaining a number of physiological and psychological effects of color, in explaining the effects of age on color vision, and in explaining the Chinese chromophototherapy. We also discuss its application to neuroimmunology. This research provides the foundation of the clinical applications of chromophototherapy.

  14. [True color accuracy in digital forensic photography].

    Science.gov (United States)

    Ramsthaler, Frank; Birngruber, Christoph G; Kröll, Ann-Katrin; Kettner, Mattias; Verhoff, Marcel A

    2016-01-01

    Forensic photographs not only need to be unaltered and authentic and capture context-relevant images, along with certain minimum requirements for image sharpness and information density, but color accuracy also plays an important role, for instance, in the assessment of injuries or taphonomic stages, or in the identification and evaluation of traces from photos. The perception of color not only varies subjectively from person to person, but as a discrete property of an image, color in digital photos is also to a considerable extent influenced by technical factors such as lighting, acquisition settings, camera, and output medium (print, monitor). For these reasons, consistent color accuracy has so far been limited in digital photography. Because images usually contain a wealth of color information, especially for complex or composite colors or shades of color, and the wavelength-dependent sensitivity to factors such as light and shadow may vary between cameras, the usefulness of issuing general recommendations for camera capture settings is limited. Our results indicate that true image colors can best and most realistically be captured with the SpyderCheckr technical calibration tool for digital cameras tested in this study. Apart from aspects such as the simplicity and quickness of the calibration procedure, a further advantage of the tool is that the results are independent of the camera used and can also be used for the color management of output devices such as monitors and printers. The SpyderCheckr color-code patches allow true colors to be captured more realistically than with a manual white balance tool or an automatic flash. We therefore recommend that the use of a color management tool should be considered for the acquisition of all images that demand high true color accuracy (in particular in the setting of injury documentation).

  15. P1-15: Categorical Color Perception of LED Illuminant Color for Deuteranomals

    Directory of Open Access Journals (Sweden)

    Saeko Oishi

    2012-10-01

    Full Text Available Color information has great value in our everyday lives, but it is not mindful of people with color vision deficiency (CVD. We can choose several color names to categorize a lot of colors around us. Eleven color names (white, black, red, green, yellow, blue, brown, orange, pink, and gray are known as basic color categories, but people with CVD cannot necessarily describe colors as people who are color vision normal (CVN do. Previous studies showed that it was hard for people with CVD to discriminate illuminant color from object color, and their color perception changed largely depending on experimental conditions. In this study we investigated categorical color perception of illuminant color for deuteranomals, using a mixture of light which consists of a red, a green, and a blue LED as a test stimulus. We tested those stimuli with three luminance levels (180 cd/m2, 18 cd/m2, 1.8 cd/m2 and two visual angles (10 deg, 0.5 deg. Subjects were three deuteranomals and three people who are CVN. Our result showed that the categorical color of mild deuteranomals was similar to that of those who were CVN, but that of severe deuteranomals was not. Severe deuteranomals judged more low chromatic colors as achromatic colors than those who were CVN. The smaller visual angle or lower luminance level the test stimulus had, the more deuteranomals confused color. The results suggest that the effect of the Bezold-Brucke phenomenon is greater to deuteranomals than to those who are CVN. Furthermore, deuteranomals use not only chromatic information but also luminance information when they describe color.

  16. [Research on developping the spectral dataset for Dunhuang typical colors based on color constancy].

    Science.gov (United States)

    Liu, Qiang; Wan, Xiao-Xia; Liu, Zhen; Li, Chan; Liang, Jin-Xing

    2013-11-01

    The present paper aims at developping a method to reasonably set up the typical spectral color dataset for different kinds of Chinese cultural heritage in color rendering process. The world famous wall paintings dating from more than 1700 years ago in Dunhuang Mogao Grottoes was taken as typical case in this research. In order to maintain the color constancy during the color rendering workflow of Dunhuang culture relics, a chromatic adaptation based method for developping the spectral dataset of typical colors for those wall paintings was proposed from the view point of human vision perception ability. Under the help and guidance of researchers in the art-research institution and protection-research institution of Dunhuang Academy and according to the existing research achievement of Dunhuang Research in the past years, 48 typical known Dunhuang pigments were chosen and 240 representative color samples were made with reflective spectral ranging from 360 to 750 nm was acquired by a spectrometer. In order to find the typical colors of the above mentioned color samples, the original dataset was devided into several subgroups by clustering analysis. The grouping number, together with the most typical samples for each subgroup which made up the firstly built typical color dataset, was determined by wilcoxon signed rank test according to the color inconstancy index comprehensively calculated under 6 typical illuminating conditions. Considering the completeness of gamut of Dunhuang wall paintings, 8 complementary colors was determined and finally the typical spectral color dataset was built up which contains 100 representative spectral colors. The analytical calculating results show that the median color inconstancy index of the built dataset in 99% confidence level by wilcoxon signed rank test was 3.28 and the 100 colors are distributing in the whole gamut uniformly, which ensures that this dataset can provide reasonable reference for choosing the color with highest

  17. On the complexity of the colorful directed paths in vertex coloring of digraphs

    Directory of Open Access Journals (Sweden)

    S. Saqaeeyan

    2013-06-01

    Full Text Available The colorful paths and rainbow paths have been considered by severalauthors.A colorful directed path in a digraph $G$ is a directed path with $chi(G$ vertices whose colors are different. A $v$-colorful directed path is such a directed path, starting from $v$. We prove that for a given $3$-regular triangle-free digraph $G$ determining whether there is a proper $chi(G$-coloring of $G$such that for every $v in V (G$, there exists a $v$-colorful directed path is $ mathbf{NP} $-complete.

  18. Individualization of 2D color maps for people with color vision deficiencies

    KAUST Repository

    Waldin, Nicholas

    2016-12-13

    2D color maps are often used to visually encode complex data characteristics such as heat or height. The comprehension of color maps in visualization is affected by the display (e.g., a monitor) and the perceptual abilities of the viewer. People with color vision deficiencies, such as red-green blindness, face difficulties when using conventional color maps. We propose a novel method for adapting a color map to an individual person, by having the user sort lines extracted from a given color map.

  19. Color Regeneration from Reflective Color Sensor Using an Artificial Intelligent Technique

    Directory of Open Access Journals (Sweden)

    Hayriye Altural

    2010-09-01

    Full Text Available A low-cost optical sensor based on reflective color sensing is presented. Artificial neural network models are used to improve the color regeneration from the sensor signals. Analog voltages of the sensor are successfully converted to RGB colors. The artificial intelligent models presented in this work enable color regeneration from analog outputs of the color sensor. Besides, inverse modeling supported by an intelligent technique enables the sensor probe for use of a colorimetric sensor that relates color changes to analog voltages.

  20. Lateralization of categorical perception of color changes with color term acquisition

    OpenAIRE

    Franklin, A.; Drivonikou, G. V.; Clifford, A.; Kay, P; Regier, T.; Davies, I. R. L.

    2008-01-01

    Categorical perception (CP) of color is the faster and more accurate discrimination of two colors from different categories than two colors from the same category, even when same- and different-category chromatic separations are equated. In adults, color CP is lateralized to the left hemisphere (LH), whereas in infants, it is lateralized to the right hemisphere (RH). There is evidence that the LH bias in color CP in adults is due to the influence of color terms in the LH. Here we show that th...

  1. Functional silk: colored and luminescent.

    Science.gov (United States)

    Tansil, Natalia C; Koh, Leng Duei; Han, Ming-Yong

    2012-03-15

    Silkworm silk is among the most widely used natural fibers for textile and biomedical applications due to its extraordinary mechanical properties and superior biocompatibility. A number of physical and chemical processes have also been developed to reconstruct silk into various forms or to artificially produce silk-like materials. In addition to the direct use and the delicate replication of silk's natural structure and properties, there is a growing interest to introduce more new functionalities into silk while maintaining its advantageous intrinsic properties. In this review we assess various methods and their merits to produce functional silk, specifically those with color and luminescence, through post-processing steps as well as biological approaches. There is a highlight on intrinsically colored and luminescent silk produced directly from silkworms for a wide range of applications, and a discussion on the suitable molecular properties for being incorporated effectively into silk while it is being produced in the silk gland. With these understanding, a new generation of silk containing various functional materials (e.g., drugs, antibiotics and stimuli-sensitive dyes) would be produced for novel applications such as cancer therapy with controlled release feature, wound dressing with monitoring/sensing feature, tissue engineering scaffolds with antibacterial, anticoagulant or anti-inflammatory feature, and many others.

  2. Processing Color in Astronomical Imagery

    CERN Document Server

    Arcand, Kimberly K; Rector, Travis; Levay, Zoltan G; DePasquale, Joseph; Smarr, Olivia

    2013-01-01

    Every year, hundreds of images from telescopes on the ground and in space are released to the public, making their way into popular culture through everything from computer screens to postage stamps. These images span the entire electromagnetic spectrum from radio waves to infrared light to X-rays and gamma rays, a majority of which is undetectable to the human eye without technology. Once these data are collected, one or more specialists must process the data to create an image. Therefore, the creation of astronomical imagery involves a series of choices. How do these choices affect the comprehension of the science behind the images? What is the best way to represent data to a non-expert? Should these choices be based on aesthetics, scientific veracity, or is it possible to satisfy both? This paper reviews just one choice out of the many made by astronomical image processors: color. The choice of color is one of the most fundamental when creating an image taken with modern telescopes. We briefly explore the ...

  3. Color, light, and altruistic creation

    Science.gov (United States)

    Charnay, Yves

    2002-06-01

    It seems necessary to me to combine a certain technical inventivity with plastic creation, a particular poetry arises from this relation. The sources of inspiration for works, especially works in which color plays a pre-eminent role, do not only come from nature. The fantasy of the creators evolves and changes thanks to discoveries and technological inventions. My work as a painter has made me particularly sensitive to the diversity of the plastic writings in general and to the chromatic writings in particular. (1) Environmental creation imposes a renewal of the means of creation. Conducting experimental works, I study the particularities of light, mainly its incidence on materials (transmission, reflection, colors, textures, etc.) and its mobility. These works are a source of inspiration for my architectural works and nurture my lectures at the Ecole Nationale Superieure des Arts Decoratifs (National College of Decorative Arts). Environmental creation also imposes some qualities on the artist since he, whether he serves a social entity or a person, serves the whole collectivity. Environmental creation has to be envisaged as an altruistic approach.

  4. Electromagnetic currents induced by color fields

    CERN Document Server

    Tanji, Naoto

    2015-01-01

    The quark production in classical color fields is investigated with a focus on the induction of an electromagnetic current by produced quarks. We show that the SU(2) and the SU(3) theories lead significantly different results for the electromagnetic current. In uniform SU(2) color fields, the net electromagnetic current is not generated, while for SU(3) the net current is induced depending on the color direction of background fields. Also the numerical study of the quark production in inhomogeneous color fields is done. Motivated by gauge field configurations provided by the color glass condensate framework, we introduce an ensemble of randomly distributed color electric fluxtubes. The spectrum of photons emitted from the quarks by a classical process is shown.

  5. Color Data Compensation for Illumination Change

    Institute of Scientific and Technical Information of China (English)

    Pranchalee Rattanasakornchai; Yasushi Hoshino; Chun Weilin

    2004-01-01

    Compensation method for illumination change, which has big influences on the characteristics of imaging system, is studied. On the condition that color chart is placed in the view of camera, the imaging system recognizes the color chart and the signals from the camera are processed by using the color chart data. Concerning the light from the window, and fluorescent light, it is confirmed that color chart is possible to be recognized and the color system is corrected to the expected chart signal within the error 10 % by considering quadratic terms of RGB. This method is considered to improve the accuracy of motion detection and also to better video communication by realizing preferalle color reproduction.

  6. An adaptively spatial color gamut mapping algorithm

    Institute of Scientific and Technical Information of China (English)

    Xiandou Zhang; Haisong Xu

    2009-01-01

    To improve the accuracy of color image reproduction from displays to printers,an adaptively spatial color gamut mapping algorithm(ASCGMA)is proposed.In this algorithm,the compression degree of outof-reproduction-gamut color is not only related to the position of the color in CIELCH color space,but also depending on the neighborhood of the color to be mapped.The psychophysical experiment of pair comparison ks carried out to evaluate and compare this new algorithm with the HPMINDE and SGCK gamut mapping algorithms recommended by the International Commission on Illumination(CIE).The experimental results indicate that the proposed algorithm outperforms the algorithms of HPMINDE and SGCK except for the very dark images.

  7. Bio-inspired variable structural color materials.

    Science.gov (United States)

    Zhao, Yuanjin; Xie, Zhuoying; Gu, Hongcheng; Zhu, Cun; Gu, Zhongze

    2012-04-21

    Natural structural color materials, especially those that can undergo reversible changes, are attracting increasing interest in a wide variety of research fields. Inspired by the natural creatures, many elaborately nanostructured photonic materials with variable structural colors were developed. These materials have found important applications in switches, display devices, sensors, and so on. In this critical review, we will provide up-to-date research concerning the natural and bio-inspired photonic materials with variable structural colors. After introducing the variable structural colors in natural creatures, we will focus on the studies of artificial variable structural color photonic materials, including their bio-inspired designs, fabrications and applications. The prospects for the future development of these fantastic variable structural color materials will also be presented. We believe this review will promote the communications among biology, bionics, chemistry, optical physics, and material science (196 references).

  8. Structural colors: from plasmonic to carbon nanostructures.

    Science.gov (United States)

    Xu, Ting; Shi, Haofei; Wu, Yi-Kuei; Kaplan, Alex F; Ok, Jong G; Guo, L Jay

    2011-11-18

    In addition to colorant-based pigmentation, structure is a major contributor to a material's color. In nature, structural color is often caused by the interaction of light with dielectric structures whose dimensions are on the order of visible-light wavelengths. Different optical interactions including multilayer interference, light scattering, the photonic crystal effect, and combinations thereof give rise to selective transmission or reflection of particular light wavelengths, which leads to the generation of structural color. Recent developments in nanofabrication of plasmonic and carbon nanostructures have opened another efficient way to control light properties at the subwavelength scale, including visible-light wavelength selection, which can produce structural color. In this Concept, the most relevant and representative achievements demonstrated over the last several years are presented and analyzed. These plasmonic and carbon nanostructures are believed to offer great potential for high-resolution color displays and spectral filtering applications.

  9. Synesthetic colors for Japanese late acquired graphemes.

    Science.gov (United States)

    Asano, Michiko; Yokosawa, Kazuhiko

    2012-06-01

    Determinants of synesthetic color choice for the Japanese logographic script, Kanji, were studied. The study investigated how synesthetic colors for Kanji characters, which are usually acquired later in life than other types of graphemes in Japanese language (phonetic characters called Hiragana and Katakana, and Arabic digits), are influenced by linguistic properties such as phonology, orthography, and meaning. Of central interest was a hypothesized generalization process from synesthetic colors for graphemes, learned prior to acquisition of Kanji, to Kanji characters learned later. Results revealed that color choices for Kanji characters depend on meaning and phonological information. Some results suggested that colors are generalized from Hiragana characters and Arabic digits to Kanji characters via phonology and meaning, respectively. Little influence of orthographic information was observed. The findings and approach of this study contributes to a clarification of the mechanism underlying grapheme-color synesthesia, especially in terms of its relationship to normal language processing.

  10. Quaternion Diffusion for Color Image Filtering

    Institute of Scientific and Technical Information of China (English)

    Zhong-Xuan Liu; Shi-Guo Lian; Zhen Ren

    2006-01-01

    How to combine color and multiscale information is a fundamental question for computer vision, and quite a few color diffusion techniques have been presented. Most of these proposed techniques do not consider the direct interactions between color channel pairs. In this paper, a new method of color diffusion considering these effects is presented, which is based on quaternion diffusion (QD) equation. In addition to showing the solution to linear QD and its analysis, one form of nonlinear QD is discussed. Compared with other color diffusion techniques, considering the interactions between channel pairs, QD has the following advantages: 1) staircasing effect is avoided; 2) as diffusion tensor, the image derivative is regu larized without requiring additional convolution; 3) less time is needed. Experimental results demonstrate the effectiveness of linear and nonlinear QD applied to natural color images for denoising by both visual and quantitative evaluations.

  11. Hepatitis Diagnosis Using Facial Color Image

    Science.gov (United States)

    Liu, Mingjia; Guo, Zhenhua

    Facial color diagnosis is an important diagnostic method in traditional Chinese medicine (TCM). However, due to its qualitative, subjective and experi-ence-based nature, traditional facial color diagnosis has a very limited application in clinical medicine. To circumvent the subjective and qualitative problems of facial color diagnosis of Traditional Chinese Medicine, in this paper, we present a novel computer aided facial color diagnosis method (CAFCDM). The method has three parts: face Image Database, Image Preprocessing Module and Diagnosis Engine. Face Image Database is carried out on a group of 116 patients affected by 2 kinds of liver diseases and 29 healthy volunteers. The quantitative color feature is extracted from facial images by using popular digital image processing techni-ques. Then, KNN classifier is employed to model the relationship between the quantitative color feature and diseases. The results show that the method can properly identify three groups: healthy, severe hepatitis with jaundice and severe hepatitis without jaundice with accuracy higher than 73%.

  12. Hypertension and color blindness in young men.

    Science.gov (United States)

    Morton, W E

    1975-05-01

    Medical data from Selective Service registrants born from 1939 to 1941 were studied in Oregon and Colorado. Among 29,119 registrants with medical information (41.3% of all registrants), 1,073 (3.6%) had definite hypertension, and 1,226 (4.2%) had some type of color blindness. In both states, there was a highly significant association between the prevalence of hypertension and the prevalence of color blindness. Thus, definite hypertension was present in 6.0% of color clind individuals but in only 3.6% of those with unimparied color vision, while color blindness occurred in 6.8% with definite hypertension, in 5.8% with borderline hypertension, and in only 4.0% with normal blood pressure. The data did not differentiate among types of color blindness, and the reason for the association is not yet evident.

  13. Prevalence of Color Vision Deficiency in Qazvin

    Directory of Open Access Journals (Sweden)

    Mohammad khalaj

    2014-01-01

    Full Text Available Background: Color vision deficiency (CVD is an X chromosome-linked recessive autosomal dominant. Determine the prevalence of color blindness in Qazvin population. Materials and Methods: In a cross sectional study color vision deficiency examined in 1853 individuals with age 10-25 years old who participated in private clinics and eye clinic of Bu-Ali hospital in Qazvin in 2010. The screening of color vision deficiency was performed using Ishihara test. Data were analyzed by SPSS-16 with χP2P test with p<0.05. Results: Mean age of participant was 17.86±4.48 years. 59.5% of them were female. 3.49% of the total population had color vision deficiency that 0.93% and 2.56% were female and male respectively. Conclusion: color vision deficiency must be noticed by decision makers in health field for screen planning.

  14. Application of Graph Coloring to Biological Networks

    CERN Document Server

    Khor, Susan

    2009-01-01

    We explore the application of graph coloring to biological networks, specifically protein-protein interaction (PPI) networks. First, we find that given similar conditions (i.e. number of nodes, number of links, degree distribution and clustering), fewer colors are needed to color disassortative (high degree nodes tend to connect to low degree nodes and vice versa) than assortative networks. Fewer colors create fewer independent sets which in turn imply higher concurrency potential for a network. Since PPI networks tend to be disassortative, we suggest that in addition to functional specificity and stability proposed previously by Maslov and Sneppen (Science 296, 2002), the disassortative nature of PPI networks may promote the ability of cells to perform multiple, crucial and functionally diverse tasks concurrently. Second, since graph coloring is closely related to the presence of cliques in a graph, the significance of node coloring information to the problem of identifying protein complexes, i.e. dense subg...

  15. Tongue Color Analysis for Medical Application

    Directory of Open Access Journals (Sweden)

    Bob Zhang

    2013-01-01

    Full Text Available An in-depth systematic tongue color analysis system for medical applications is proposed. Using the tongue color gamut, tongue foreground pixels are first extracted and assigned to one of 12 colors representing this gamut. The ratio of each color for the entire image is calculated and forms a tongue color feature vector. Experimenting on a large dataset consisting of 143 Healthy and 902 Disease (13 groups of more than 10 samples and one miscellaneous group, a given tongue sample can be classified into one of these two classes with an average accuracy of 91.99%. Further testing showed that Disease samples can be split into three clusters, and within each cluster most if not all the illnesses are distinguished from one another. In total 11 illnesses have a classification rate greater than 70%. This demonstrates a relationship between the state of the human body and its tongue color.

  16. Conditional and Unique Coloring of Graphs

    CERN Document Server

    Reddy, P Venkata Subba

    2011-01-01

    For integers $k, r > 0$, a conditional $(k,r)$-coloring of a graph $G$ is a proper $k$-coloring of the vertices of $G$ such that every vertex $v$ of degree $d(v)$ in $G$ is adjacent to at least $\\min\\{r, d(v)\\}$ differently colored vertices. Given $r$, the smallest integer $k$ for which $G$ has a conditional $(k,r)$-coloring is called the $r$th order conditional chromatic number $\\chi_r(G)$ of $G$. We give results (exact values or bounds for $\\chi_r(G)$, depending on $r$) related to the conditional coloring of some graphs. We introduce \\emph{unique conditional colorability} and give some related results. (Keywords. cartesian product of graphs; conditional chromatic number; gear graph; join of graphs.)

  17. Color and Contingency in Robert Boyle's Works.

    Science.gov (United States)

    Baker, Tawrin

    2015-01-01

    This essay investigates the relationship between color and contingency in Robert Boyle's Experiments and Considerations Touching Colours (1664) and his essays on the unsuccessfulness of experiments in Certain Physiological Essays (1661). In these two works Boyle wrestles with a difficult practical and philosophical problem with experiments, which he calls the problem of contingency. In Touching Colours, the problem of contingency is magnified by the much-debated issue of whether color had any deep epistemic importance. His limited theoretical principle guiding him in Touching Colours, that color is but modified light, further exacerbated the problem. Rather than theory, Boyle often relied on craftsmen, whose mastery of color phenomena was, Boyle mentions, brought about by economic forces, to determine when colors were indicators of important 'inward' properties of substances, and thus to secure a solid foundation for his experimental history of color.

  18. Color segmentation in the HSI color space using the K-means algorithm

    Science.gov (United States)

    Weeks, Arthur R.; Hague, G. Eric

    1997-04-01

    Segmentation of images is an important aspect of image recognition. While grayscale image segmentation has become quite a mature field, much less work has been done with regard to color image segmentation. Until recently, this was predominantly due to the lack of available computing power and color display hardware that is required to manipulate true color images (24-bit). TOday, it is not uncommon to find a standard desktop computer system with a true-color 24-bit display, at least 8 million bytes of memory, and 2 gigabytes of hard disk storage. Segmentation of color images is not as simple as segmenting each of the three RGB color components separately. The difficulty of using the RGB color space is that it doesn't closely model the psychological understanding of color. A better color model, which closely follows that of human visual perception is the hue, saturation, intensity model. This color model separates the color components in terms of chromatic and achromatic information. Strickland et al. was able to show the importance of color in the extraction of edge features form an image. His method enhances the edges that are detectable in the luminance image with information from the saturation image. Segmentation of both the saturation and intensity components is easily accomplished with any gray scale segmentation algorithm, since these spaces are linear. The modulus 2(pi) nature of the hue color component makes its segmentation difficult. For example, a hue of 0 and 2(pi) yields the same color tint. Instead of applying separate image segmentation to each of the hue, saturation, and intensity components, a better method is to segment the chromatic component separately from the intensity component because of the importance that the chromatic information plays in the segmentation of color images. This paper presents a method of using the gray scale K-means algorithm to segment 24-bit color images. Additionally, this paper will show the importance the hue

  19. Color calibration of an RGB camera mounted in front of a microscope with strong color distortion.

    Science.gov (United States)

    Charrière, Renée; Hébert, Mathieu; Trémeau, Alain; Destouches, Nathalie

    2013-07-20

    This paper aims at showing that performing color calibration of an RGB camera can be achieved even in the case where the optical system before the camera introduces strong color distortion. In the present case, the optical system is a microscope containing a halogen lamp, with a nonuniform irradiance on the viewed surface. The calibration method proposed in this work is based on an existing method, but it is preceded by a three-step preprocessing of the RGB images aiming at extracting relevant color information from the strongly distorted images, taking especially into account the nonuniform irradiance map and the perturbing texture due to the surface topology of the standard color calibration charts when observed at micrometric scale. The proposed color calibration process consists first in computing the average color of the color-chart patches viewed under the microscope; then computing white balance, gamma correction, and saturation enhancement; and finally applying a third-order polynomial regression color calibration transform. Despite the nonusual conditions for color calibration, fairly good performance is achieved from a 48 patch Lambertian color chart, since an average CIE-94 color difference on the color-chart colors lower than 2.5 units is obtained.

  20. EVALUATION OF FOOD COLOR CONSUMPTION AND DETERMINING COLOR TYPE BY THIN LAYER CHROMATOGRAPHY

    Directory of Open Access Journals (Sweden)

    Fereshteh Farzianpour

    2013-01-01

    Full Text Available The aim of this research was to investigate the role of the social demographic parameters of the people in charge of the facilities producing pastry, poolak (a type of coin-shaped candy and rock candy in the consumption of food colors and to determine color type by thin layer chromatography in Shahr-e-kord city in 2011. This research was an interventional-analytical study and its target population is the people in charge of the facilities producing pastry, poolak and rock candy in Shahr-e-kord city. Social demographic data of the participants were collected using checklists and 720 samples of pastry, poolak and rock candy weighing at least 250 gr were randomly taken over a period of 10 months. With respect to color additives, the samples were analyzed by Thin Layer Chromatography (TLC in four groups: natural colors permitted artificial colors, forbidden artificial colors and without colors. 48.47% contained food color and 6.52% contained forbidden artificial food color. Sunset Yellow was the color the most consumed among the colors used. Regarding the results obtained, there is a high rate of consumption of artificial colors (41.22%, sunset Yellow being the most consumed. Therefore, it is of great importance to raise the awareness and change the attitude of the people in charge in these jobs as well as the consumers with regard to the side effects of artificial colors, which can be done through the mass media and NGOs.

  1. Magnetoresponsive Photonic Microspheres with Structural Color Gradient.

    Science.gov (United States)

    Lee, Seung Yeol; Choi, Jongkook; Jeong, Jong-Ryul; Shin, Jung H; Kim, Shin-Hyun

    2017-02-06

    Photonic Janus particles are created by alternately sputtering silica and titania on microspheres in order to obtain a structural color gradient. In addition, the microspheres are rendered magnetoresponsive. The Janus microspheres with optical and magnetic anisotropy enable on-demand control over orientation and structural color through manipulation of an external magnetic field, thereby being useful as active color pigments for reflection-mode displays.

  2. Designing for Color in Additive Manufacturing

    DEFF Research Database (Denmark)

    Eiríksson, Eyþór Rúnar; Luongo, Andrea; Frisvad, Jeppe Revall

    2016-01-01

    In this paper we present a color design pipeline for 3D printed or additively manufactured parts. We demonstrate how to characterize and calibrate a commercial printer and how to obtain its forward and backward color transformation models. We present results from our assistive color design tool......, allowing for colorimetric accurate prints and visualization of the printed outcome, prior to print. Lastly, we demonstrate our pipeline by accurately reproducing a real physical object....

  3. Optical Spectra and Color of Silver Colloids

    Directory of Open Access Journals (Sweden)

    N.L. Dmitruk

    2013-10-01

    Full Text Available In present work, the color features of the aqueous silver suspensions were investigated. Color systems CIE XYZ and CIELAB are considered. In the case of low concentrations of nanoparticles chromaticity coordinates were determined from the transmission spectra of the colloids. For high concentrations of nanoparticles, when the multiple scattering effects play a key role and the medium turns to be turbid, the color of nanoparticles was found using the Kubelka-Munk relation. Experimental data is compared with that calculated from the Mie theory. Color features of a planar array of non-interacting silver nanoparticles are discussed for the first time.

  4. Colorization by classifying the prior knowledge

    Institute of Scientific and Technical Information of China (English)

    DU Weiwei

    2011-01-01

    When a one-dimensional luminance scalar is replaced by a vector of a colorful multi-dimension for every pixel of a monochrome image,the process is called colorization.However,colorization is under-constrained.Therefore,the prior knowledge is considered and given to the monochrome image.Colorization using optimization algorithm is an effective algorithm for the above problem.However,it cannot effectively do with some images well without repeating experiments for confirming the place of scribbles.In this paper,a colorization algorithm is proposed,which can automatically generate the prior knowledge.The idea is that firstly,the prior knowledge crystallizes into some points of the prior knowledge which is automatically extracted by downsampling and upsampling method.And then some points of the prior knowledge are classified and given with corresponding colors.Lastly,the color image can be obtained by the color points of the prior knowledge.It is demonstrated that the proposal can not only effectively generate the prior knowledge but also colorize the monochrome image according to requirements of user with some experiments.

  5. Color and polarization vision in foraging Papilio.

    Science.gov (United States)

    Kinoshita, Michiyo; Arikawa, Kentaro

    2014-06-01

    This paper gives an overview of behavioral studies on the color and polarization vision of the Japanese yellow swallowtail butterfly, Papilio xuthus. We focus on indoor experiments on foraging individuals. Butterflies trained to visit a disk of certain color correctly select that color among various other colors and/or shades of gray. Correct selection persists under colored illumination, but is systematically shifted by background colors, indicating color constancy and simultaneous color contrast. While their eyes contain six classes of spectral receptors, their wavelength discrimination performance indicates that their color vision is tetrachromatic. P. xuthus innately prefers brighter targets, but can be trained to select dimmer ones under certain conditions. Butterflies trained to a dark red stimulus select an orange disk presented on a bright gray background over one on dark gray. The former probably appears darker to them, indicating brightness contrast. P. xuthus has a strong innate preference for vertically polarized light, but the selection of polarized light changes depending on the intensity of simultaneously presented unpolarized light. Discrimination of polarization also depends on background intensity. Similarities between brightness and polarization vision suggest that P. xuthus perceive polarization angle as brightness, such that vertical polarization appears brighter than horizontal polarization.

  6. Facial expression recognition in perceptual color space.

    Science.gov (United States)

    Lajevardi, Seyed Mehdi; Wu, Hong Ren

    2012-08-01

    This paper introduces a tensor perceptual color framework (TPCF) for facial expression recognition (FER), which is based on information contained in color facial images. The TPCF enables multi-linear image analysis in different color spaces and demonstrates that color components provide additional information for robust FER. Using this framework, the components (in either RGB, YCbCr, CIELab or CIELuv space) of color images are unfolded to two-dimensional (2- D) tensors based on multi-linear algebra and tensor concepts, from which the features are extracted by Log-Gabor filters. The mutual information quotient (MIQ) method is employed for feature selection. These features are classified using a multi-class linear discriminant analysis (LDA) classifier. The effectiveness of color information on FER using low-resolution and facial expression images with illumination variations is assessed for performance evaluation. Experimental results demonstrate that color information has significant potential to improve emotion recognition performance due to the complementary characteristics of image textures. Furthermore, the perceptual color spaces (CIELab and CIELuv) are better overall for facial expression recognition than other color spaces by providing more efficient and robust performance for facial expression recognition using facial images with illumination variation.

  7. Do instantons like a colorful background?

    Energy Technology Data Exchange (ETDEWEB)

    Gies, H.; Pawlowski, J.M.; Wetterich, C. [Heidelberg Univ. (Germany). Inst. fuer Theoretische Physik; Jaeckel, J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2006-08-15

    We investigate chiral symmetry breaking and color symmetry breaking in QCD. The effective potential of the corresponding scalar condensates is discussed in the presence of non-perturbative contributions from the semiclassical one-instanton sector. We concentrate on a color singlet scalar background which can describe chiral condensation, as well as a color cotet scalar background which can generate mass for the gluons. Whereas a non-vanishing singlet chiral field is favored by the instantons, we have found no indication for a preference of color octet backgrounds. (orig.)

  8. Data Security With Colors Using Rsa

    Directory of Open Access Journals (Sweden)

    G. Sankara Rao,

    2014-04-01

    Full Text Available Data Security with Colors using RSA technique that integrates the RGB Color model with the well-known public key cryptographic algorithm RSA (Rivest, Shamir and Adleman. This model provides both confidentiality and authentication to the data sent across the network. RSA algorithm uses public key and private key to encrypt and decrypt the data and thus provides confidentiality. But the public key is known to everyone and so anyone can encrypt the data and send the message. Hence authentication of users is needed. In this technique we use RGB color model to provide authentication. Every user will have a unique color assigned to him. A sender must know the receiver’s color to send a message. The color value is encrypted using a key which is used as a password while decrypting the message. To decrypt the message, the receiver must provide his color values. If the decrypted color values and his color values are equal then the sender and receiver are send to be authentic. The data encryption and decryption follows RSA procedure. Thus both authentication and confidentiality are provided for the data.

  9. Charged black holes in colored Lifshitz spacetimes

    Directory of Open Access Journals (Sweden)

    Zhong-Ying Fan

    2015-04-01

    Full Text Available We consider Einstein gravities coupled to a cosmological constant and SU(2 Yang–Mills fields in four and five dimensions. We find that the theories admit colored Lifshitz solutions with dynamic exponents z>1. We study the wave equations of the SU(2 scalar triplet in the bulk, and find that the vacuum color modifies the scaling dimensions of the dual operators. We also introduce a Maxwell field and construct exact solutions of electrically-charged black holes that approach the D=4, z=3 and D=5, z=4 colored Lifshitz spacetimes. We derive the thermodynamical first law for general colored and charged Lifshitz black holes.

  10. The color space of a graph

    DEFF Research Database (Denmark)

    Jensen, T.R.; Thomassen, Carsten

    2000-01-01

    If k is a prime power, and G is a graph with n vertices, then a k-coloring of G may be considered as a vector in GF(k)(n). We prove that the subspace of GF(3)(n) spanned by all 3-colorings of a planar triangle-free graph with n vertices has dimension n. In particular, any such graph has at least n...... - 1 nonequivalent 3-colorings, and the addition of any edge or any vertex of degree 3 results in a 3-colorable graph. (C) 2000 John Wiley & Sons, Inc....

  11. Pet fur color and texture classification

    Science.gov (United States)

    Yen, Jonathan; Mukherjee, Debarghar; Lim, SukHwan; Tretter, Daniel

    2007-01-01

    Object segmentation is important in image analysis for imaging tasks such as image rendering and image retrieval. Pet owners have been known to be quite vocal about how important it is to render their pets perfectly. We present here an algorithm for pet (mammal) fur color classification and an algorithm for pet (animal) fur texture classification. Per fur color classification can be applied as a necessary condition for identifying the regions in an image that may contain pets much like the skin tone classification for human flesh detection. As a result of the evolution, fur coloration of all mammals is caused by a natural organic pigment called Melanin and Melanin has only very limited color ranges. We have conducted a statistical analysis and concluded that mammal fur colors can be only in levels of gray or in two colors after the proper color quantization. This pet fur color classification algorithm has been applied for peteye detection. We also present here an algorithm for animal fur texture classification using the recently developed multi-resolution directional sub-band Contourlet transform. The experimental results are very promising as these transforms can identify regions of an image that may contain fur of mammals, scale of reptiles and feather of birds, etc. Combining the color and texture classification, one can have a set of strong classifiers for identifying possible animals in an image.

  12. Anatomy of Vitis Berries During Their Coloring

    Institute of Scientific and Technical Information of China (English)

    WAN Yi-zhen; HE Pu-chao

    2002-01-01

    During 1998-1999, the course of the berry coloring and the development of the pigment cells from veraison to ripeness were studied by freeze sectioning 43 accessions of 12 Vitis species (including 10 Chinese wild species). External observation showed that the berries of most species began coloring on the fruit top surface or on the sun-lit surface, and the berry surface color was evenly distributed when the berry was ripe.Internal observation revealed that the pigment cells in a few layers between cuticle and sub-cuticle colored first, the cuticle colored from inner layers to outer layers while the sub-cuticle from outer to inner, and the cuticle cells began coloring a little earlier than the sub-cuticle ones in most species. The pigment cells developed unevenly during the berry ripening. In the beginning of berry coloring, the cell pigment density among the layers or among the cells in the same layer was different. Both the numbers of the pigmented cells and the cell pigment density increased during the berry coloring, while the former lasted a short time; however, the latter kept increasing from veraison to ripeness, and they reached the deepest color when the berry was ripe.

  13. Congenital color blindness in young Turkish men.

    Science.gov (United States)

    Citirik, Mehmet; Acaroglu, Golge; Batman, Cosar; Zilelioglu, Orhan

    2005-04-01

    We investigated a healthy population of men from different regions of Turkey for the presence of congenital red-green color blindness. Using Ishihara pseudoisochromatic plates, 941 healthy men from the Turkish army were tested for congenital red-green color blindness. The prevalence of red-green color blindness was 7.33 +/- 0.98% (5.10% protans and 2.23% deutans). These ratios were higher than other reported samples from Mediterranean Europe. Higher percentages of color blindness were found in regions with a lower education level and more consanguineous marriages.

  14. Unsupervised Color-texture Image Segmentation

    Institute of Scientific and Technical Information of China (English)

    YU Sheng-yang; ZHANG Fan; WANG Yong-gang; YANG Jie

    2008-01-01

    The measure J in J value segmentation (JSEG) falls to represent the discontinuity of color, which degrades the robustness and discrimination of JSEG. An improved approach for JSEG algorithm was proposed for unsupervised color-texture image segmentation. The texture and photometric invariant edge information were combined, which results in a discriminative measure for color-texture homogeneity. Based on the image whose pixel values are values of the new measure, region growing-merging algorithm used in JSEG was then employed to segment the image. Finally, experiments on a variety of real color images demonstrate performance improvement due to the proposed method.

  15. Effect of glucuronosylation on anthocyanin color stability.

    Science.gov (United States)

    Osmani, Sarah Anne; Hansen, Esben Halkjaer; Malien-Aubert, Céline; Olsen, Carl-Erik; Bak, Søren; Møller, Birger Lindberg

    2009-04-22

    The effect of glucuronosylation on the color stability of anthocyanins was investigated using glucuronosylated anthocyanins isolated from the flower petals of the red daisy (Bellis perennis) or obtained by enzymatic in vitro synthesis using heterologously expressed red daisy glucuronosyltransferase BpUGT94B1. Color stability toward light and heat stress was assessed by monitoring CIELAB color coordinates and stability at pH 7.0 by A(550). Cyanidin-3-O-2''-O-glucuronosylglucoside showed improved color stability in response to light compared to both cyanidin 3-O-glucoside and cyanidin 3-O-2''-O-diglucoside. A similar increase in color stability was not observed following heat treatment. Glucuronosylation did not increase the stability of anthocyanins at pH 7.0 as determined by A(550). To test for a possible effect of glucuronosylation on the color stability of anthocyanins in plant extracts used for food coloration, an elderberry (Sambucus nigra) extract was glucuronosylated in vitro. Glucuronosylation of approximately 50% of total anthocyanins proceeded fast and resulted in increased color stability in response to both heat and light. The data show that glucuronosylation may be used to stabilize industrially used extracts of natural colorants.

  16. Color in Computer Vision Fundamentals and Applications

    CERN Document Server

    Gevers, Theo; van de Weijer, Joost; Geusebroek, Jan-Mark

    2012-01-01

    While the field of computer vision drives many of today’s digital technologies and communication networks, the topic of color has emerged only recently in most computer vision applications. One of the most extensive works to date on color in computer vision, this book provides a complete set of tools for working with color in the field of image understanding. Based on the authors’ intense collaboration for more than a decade and drawing on the latest thinking in the field of computer science, the book integrates topics from color science and computer vision, clearly linking theor

  17. Transferring color between three-dimensional objects

    Science.gov (United States)

    Shen, Hui-Liang; Xin, John H.

    2005-04-01

    A framework for transferring image-based color between three-dimensional objects by the use of a dichromatic reflection model is proposed. The framework addresses the following issues: (1) accurate recovery of an implicit geometric coefficient, (2) calculation of body color, (3) color transfer between different illuminants, and (4) segmentation of multicolored regions. The experimental results show that high color accuracy and photorealistic effects of the synthesized images can be achieved. The proposed technique has wide applications in image-based design and visualization of three-dimensional objects.

  18. Dihyperons in chiral color dielectric model

    Indian Academy of Sciences (India)

    S C Phatak

    2003-11-01

    The mass of the dibaryon having spin, parity =0+, isospin = 0 and strangeness -2 is computed using chiral color dielectric model. The bare wave function is constructed as a product of two color-singlet three-quark clusters and then it is properly antisymmetrized by considering appropriate exchange operators for spin, flavor and color. Color magnetic energy due to gluon exchange, meson self energy and energy correction due to center of mass motion are computed. The calculation shows that the mass of the particle is 80 to 160 MeV less than twice mass.

  19. Natural Colorants: Historical, Processing and Sustainable Prospects.

    Science.gov (United States)

    Yusuf, Mohd; Shabbir, Mohd; Mohammad, Faqeer

    2017-02-01

    With the public's mature demand in recent times pressurized the textile industry for use of natural colorants, without any harmful effects on environment and aquatic ecosystem, and with more developed functionalities simultaneously. Advanced developments for the natural bio-resources and their sustainable use for multifunctional clothing are gaining pace now. Present review highlights historical overview of natural colorants, classification and predominantly processing of colorants from sources, application on textiles surfaces with the functionalities provided by them. Chemistry of natural colorants on textiles also discussed with relevance to adsorption isotherms and kinetic models for dyeing of textiles.

  20. Digital devices: big challenge in color management

    Science.gov (United States)

    Vauderwange, Oliver; Curticapean, Dan; Dreβler, Paul; Wozniak, Peter

    2014-09-01

    The paper will present how the students learn to find technical solutions in color management by using adequate digital devices and recognize the specific upcoming tasks in this area. Several issues, problems and their solutions will be discussed. The scientific background offer specific didactical solutions in this area of optics. Color management is the major item of this paper. Color management is a crucial responsibility for media engineers and designers. Print, screen and mobile applications must independently display the same colors. Predictability and consistency in the color representation are the aims of a color management system. This is only possible in a standardized and audited production workflow. Nowadays digital media have a fast-paced development process. An increasing number of different digital devices with different display sizes and display technologies are a great challenge for every color management system. The authors will present their experience in the field of color management. The design and development of a suitable learning environment with the required infrastructure is in the focus. The combination of theoretical and practical lectures creates a deeper understanding in the area of the digital color representation.

  1. Colored Noise Prediction Based on Neural Network

    Institute of Scientific and Technical Information of China (English)

    Gao Fei; Zhang Xiaohui

    2003-01-01

    A method for predicting colored noise by introducing prediction of nonhnear time series is presented By adopting three kinds of neural networks prediction models, the colored noise prediction is studied through changing the filter bandwidth for stochastic noise and the sampling rate for colored noise The results show that colored noise can be predicted The prediction error decreases with the increasing of the sampling rate or the narrowing of the filter bandwidth. If the parameters are selected properly, the prediction precision can meet the requirement of engineering implementation. The results offer a new reference way for increasing the ability for detecting weak signal in signal processing system

  2. The chromatic polynomial and list colorings

    DEFF Research Database (Denmark)

    Thomassen, Carsten

    2009-01-01

    We prove that, if a graph has a list of k available colors at every vertex, then the number of list-colorings is at least the chromatic polynomial evaluated at k when k is sufficiently large compared to the number of vertices of the graph.......We prove that, if a graph has a list of k available colors at every vertex, then the number of list-colorings is at least the chromatic polynomial evaluated at k when k is sufficiently large compared to the number of vertices of the graph....

  3. Lattice Associative Memories for Segmenting Color Images in Different Color Spaces

    Science.gov (United States)

    Urcid, Gonzalo; Valdiviezo-N., Juan Carlos; Ritter, Gerhard X.

    This paper describes a technique for segmenting color images in different color spaces based on lattice auto-associative memories. Basically, the min- or max auto-associative memories can be used to determine tetrahedra enclosing different subsets of image pixels. The column vectors of either memory, additively scaled, correspond to the most saturated color pixels that are the vertices of a specified tetrahedron, and any other color pixel can be considered a linear mixture of these points. The non-negative least square method is used to linearly unmix color pixels and provides the fundamental step in the unsupervised segmentation of a given input color image. We give illustrative examples to demonstrate the effectiveness of our method as well as the color separation results in four different color spaces.

  4. Color reproductivity improvement with additional virtual color filters for WRGB image sensor

    Science.gov (United States)

    Kawada, Shun; Kuroda, Rihito; Sugawa, Shigetoshi

    2013-02-01

    We have developed a high accuracy color reproduction method based on an estimated spectral reflectance of objects using additional virtual color filters for a wide dynamic range WRGB color filter CMOS image sensor. The four virtual color filters are created by multiplying the spectral sensitivity of White pixel by gauss functions which have different central wave length and standard deviation, and the virtual sensor outputs of those virtual filters are estimated from the four real output signals of the WRGB image sensor. The accuracy of color reproduction was evaluated with a Macbeth Color Checker (MCC), and the averaged value of the color difference ΔEab of 24 colors was 1.88 with our approach.

  5. Harmony between groups : nuancing traditional views of color-blindness and color-consciousness/

    OpenAIRE

    Maquil, Annemie

    2007-01-01

    Color-blindness and color-consciousness are two ideologies aiming at prejudice and negative intergroup behavior reduction. Whereas color-blindness emphasizes the importance of breaking down group differences and considering everybody as an individal similar and equal to each other, color-consciousness emphasizes the recognition and appreciation of group differences. This dissertation is about the positive and negative aspects of both ideologies, as well as about their differential effects on ...

  6. Characterization of Angle Dependent Color Travel of Printed Multi-Color Effect Pigment on Different Color Substrates

    Directory of Open Access Journals (Sweden)

    Mirica Karlovits

    2015-03-01

    Full Text Available Color-travel pigments, which exhibit much more extensive color change as well provide angle-dependent optical effect can be used in many industrial products. In present paper the multi-color effect pigment printed on three different foils with different background color (black, silver and transparent was investigated. The pigment was based on synthetically produced transparent silicon dioxide platelets coated with titanium dioxide. CIEL*a*b* values and reflection of prints were measured by multi-angle spectrophotometer at constant illumination at an angle of 45º and different viewing angles (-15º, 15°, 25º, 45º, 75º and 110º were used. The measurements of printed multi-color pigment showed that CIEL*a*b* color coordinates varied to great extents, depending on detection angles as well on color of the printing substrate. The study revealed that pigmnet printed on black background obtained significant change in color. The study has also shown that when viewing angle increases, the reflection curves decreases.

  7. Two-color infrared detector

    Science.gov (United States)

    Klem, John F; Kim, Jin K

    2014-05-13

    A two-color detector includes a first absorber layer. The first absorber layer exhibits a first valence band energy characterized by a first valence band energy function. A barrier layer adjoins the first absorber layer at a first interface. The barrier layer exhibits a second valence band energy characterized by a second valence band energy function. The barrier layer also adjoins a second absorber layer at a second interface. The second absorber layer exhibits a third valence band energy characterized by a third valence band energy function. The first and second valence band energy functions are substantially functionally or physically continuous at the first interface and the second and third valence band energy functions are substantially functionally or physically continuous at the second interface.

  8. COLOR FEATURE EXTRACTION FOR CBIR

    Directory of Open Access Journals (Sweden)

    Dr. H.B.KEKRE

    2011-12-01

    Full Text Available Content Based Image Retrieval is the application of computer vision techniques to the image retrieval problem of searching for digital images in large databases. The method of CBIR discussed in this paper can filter images based their content and would provide a better indexing and return more accurate results. In this paper we wouldbe discussing: Feature vector generation using color averaging technique, Similarity measures and Performance evaluation using randomly selected 5 query images per class out of which result of one class is discussed. Precision –Recall cross over plot is used as the performance evaluation measure to check the algorithm. As thesystem developed is generic, database consists of images from different classes. The effect due to the size of database and number of different classes is seen on the number of relevancy of the retrievals.

  9. Cobalt: for strength and color

    Science.gov (United States)

    Boland, Maeve A.; Kropschot, S.J.

    2011-01-01

    Cobalt is a shiny, gray, brittle metal that is best known for creating an intense blue color in glass and paints. It is frequently used in the manufacture of rechargeable batteries and to create alloys that maintain their strength at high temperatures. It is also one of the essential trace elements (or "micronutrients") that humans and many other living creatures require for good health. Cobalt is an important component in many aerospace, defense, and medical applications and is a key element in many clean energy technologies. The name cobalt comes from the German word kobold, meaning goblin. It was given this name by medieval miners who believed that troublesome goblins replaced the valuable metals in their ore with a substance that emitted poisonous fumes when smelted. The Swedish chemist Georg Brandt isolated metallic cobalt-the first new metal to be discovered since ancient times-in about 1735 and identified some of its valuable properties.

  10. Color speckle in laser displays

    Science.gov (United States)

    Kuroda, Kazuo

    2015-07-01

    At the beginning of this century, lighting technology has been shifted from discharge lamps, fluorescent lamps and electric bulbs to solid-state lighting. Current solid-state lighting is based on the light emitting diodes (LED) technology, but the laser lighting technology is developing rapidly, such as, laser cinema projectors, laser TVs, laser head-up displays, laser head mounted displays, and laser headlamps for motor vehicles. One of the main issues of laser displays is the reduction of speckle noise1). For the monochromatic laser light, speckle is random interference pattern on the image plane (retina for human observer). For laser displays, RGB (red-green-blue) lasers form speckle patterns independently, which results in random distribution of chromaticity, called color speckle2).

  11. Color doppler sonography in thickened gallbladder wall

    Energy Technology Data Exchange (ETDEWEB)

    Han, Sang Suk; Choi, Seok Jin; Seo, Chang Hae; Eun, Choong Ki [Inje Univ. College of Medicine, Kimhae (Korea, Republic of)

    1996-11-01

    The thickening of the gallbladder wall is a valuable finding for the diagnosis of cholecystitis, but may be seen in non-cholecystic disease as well as in acute or chronic cholecystitis. The purpose of this study is to determine the value of color Doppler sonography in differentiating the causes of thickened gallbladder wall. Ninety eight patients with thickened gallbladder wall(more than 3mm) which was not due to gallbladder cancer were prospectively evaluated with color Doppler sonography. Sixty-six cases, confirmed by pathologic reports and clinical records, were analyzed for correlation between thickened gallbladder wall and color flow signal according to the underlying causes. Of the 66 patients, 28 cases were cholecystitis and 38 cases had non-cholecystic causes such as liver cirrhosis, ascites, hepatitis, pancreatitis, renal failure, and hypoalbuminemia. Of the 28 patients with cholecystitis(12 acute, 16 chronic), 23(82%) had color Doppler flow signals in the thickened gallbladder wall. Of the 38 patients with non-cholecystic causes, eight(21%) had color Doppler flow signals. There was a statistically significant difference of color Doppler flow signals between the cholecystitis and non-cholecystic groups(p=0.0001). No significant difference of color Doppler flow signals was found between cases of acute and chronic cholecystitis. Of the 23 patients with color Doppler flow signals in 28 cases of cholecystitis, 18(78.3%) showed a linear pattern and five(21.7%) showed a spotty pattern. Of the eight patients with color Doppler flow signals in the 38 non-cholecystic cases, four(50%) showed a linear pattern and four(50%) showed a spotty pattern. In cholecystitis, a linear color Doppler flow signal pattern is a much more frequent finding than a spotty pattern. Color Doppler sonography is a useful and adequate method for determining whether a thickened gallbladder wall is the result of cholecystitis or has non-cholecystic causes.

  12. Color management: printing processes - opportunities and limitations

    Science.gov (United States)

    Ingram, Samuel T.

    2002-06-01

    Digital tools have impacted traditional methods employed to reproduce color images during the past decade. The shift from a purely photomechanical process in color reproduction to colorimetric reproduction offers tremendous opportunity in the graphic arts industry. But good things do not necessarily come to all in the same package. Printing processes possess different reproduction attributes: tone reproduction, gray balance and color correction requirements are as different as the ingredient sets selected for color reproduction. This paper will provide insight toward understanding advantages and limitations offered by the new digital technologies in printing, publishing and packaging. For the past five years the Clemson University Graphic Communications Department has conducted numerous color projects using the new digital colorimetric tools during the previous decade. Several approaches have been used including experimental research and typical production workflows. The use of colorimetric data in color reproduction has given an opportunity to realize real gains in color use, predictability and consistency. Meeting an image's separation and reproduction requirements for a specified printing process can involve disruption of the anticipated workflow. Understanding the printing process requirements and the fit within the specifications of a colorimetric workflow are critical to the successful adoption of a color managed workflow. The paper will also provide an insight into the issues and challenges experienced with a color managed workflow. The printing processes used include offset litho, narrow and wide-web flexography (paper, liner board, corrugated and film), screen printing (paper board and polycarbonates), and digital imaging with toner, ink and inkjet systems. A proposal for technology integration will be the focus of the presentation drawn from documented experiences in over 300 applications of color management tools. Discussion will include the structure of

  13. A SEVEN-COLOR THEOREM ON EDGE-FACE COLORING OF PLANE GRAPHS

    Institute of Scientific and Technical Information of China (English)

    王维凡; 张克民

    2001-01-01

    Melnikov(1975) conjectured that the edges and faces of a plane graph G can be colored with △(G) + 3 colors so that any two adjacent or incident elements receive distinct colors, where △(G) denotes the maximum degree of G. This paper proves theconjecture for the case △(G) 4.

  14. Derivation of Color Confusion Lines for Pseudo-Dichromat Observers from Color Discrimination Thresholds

    Directory of Open Access Journals (Sweden)

    Kahiro Matsudaira

    2011-05-01

    Full Text Available The objective is to develop a method of defining color confusion lines in the display RGB color space through color discrimination tasks. In the experiment, reference and test square patches were presented side by side on a CRT display. The subject's task is to set the test color where the color difference from the reference is just noticeable to him/her. In a single trial, the test color was only adjustable along one of 26 directions around the reference. Thus 26 colors with just noticeable difference (JND were obtained and made up a tube-like or an ellipsoidal shape around each reference. With color-anomalous subjects, the major axes of these shapes should be parallel to color confusion lines that have a common orientation vector corresponding to one of the cone excitation axes L, M, or S. In our method, the orientation vector was determined by minimizing the sum of the squares of the distances from JND colors to each confusion line. To assess the performance the method, the orientation vectors obtained by pseudo-dichromats (color normal observers with a dichromat simulator were compared to those theoretically calculated from the color vision model used in the simulator.

  15. Using Color and Grayscale Images to Teach Histology to Color-Deficient Medical Students

    Science.gov (United States)

    Rubin, Lindsay R.; Lackey, Wendy L.; Kennedy, Frances A.; Stephenson, Robert B.

    2009-01-01

    Examination of histologic and histopathologic microscopic sections relies upon differential colors provided by staining techniques, such as hematoxylin and eosin, to delineate normal tissue components and to identify pathologic alterations in these components. Given the prevalence of color deficiency (commonly called "color blindness")…

  16. Using Color and Grayscale Images to Teach Histology to Color-Deficient Medical Students

    Science.gov (United States)

    Rubin, Lindsay R.; Lackey, Wendy L.; Kennedy, Frances A.; Stephenson, Robert B.

    2009-01-01

    Examination of histologic and histopathologic microscopic sections relies upon differential colors provided by staining techniques, such as hematoxylin and eosin, to delineate normal tissue components and to identify pathologic alterations in these components. Given the prevalence of color deficiency (commonly called "color blindness") in the…

  17. From ultra-dense QCD towards NICA densities: Color-flavor locking and other color superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, Andreas [University of Southampton, Mathematical Sciences and STAG Research Centre, Southampton (United Kingdom)

    2016-08-15

    At asymptotically large densities and sufficiently low temperatures, quark matter is a color superconductor in the color-flavor locked phase. I present a brief discussion of this phase and of possible other color superconductors that may appear at densities reached at NICA and in the interior of compact stars. (orig.)

  18. New approach to color calibration of high fidelity color digital camera by using unique wide gamut color generator based on LED diodes

    Science.gov (United States)

    Kretkowski, M.; Shimodaira, Y.; Jabłoński, R.

    2008-11-01

    Development of a high accuracy color reproduction system requires certain instrumentation and reference for color calibration. Our research led to development of a high fidelity color digital camera with implemented filters that realize the color matching functions. The output signal returns XYZ values which provide absolute description of color. In order to produce XYZ output a mathematical conversion must be applied to CCD output values introducing a conversion matrix. The conversion matrix coefficients are calculated by using a color reference with known XYZ values and corresponding output signals from the CCD sensor under each filter acquisition from a certain amount of color samples. The most important feature of the camera is its ability to acquire colors from the complete theoretically visible color gamut due to implemented filters. However market available color references such as various color checkers are enclosed within HDTV gamut, which is insufficient for calibration in the whole operating color range. This led to development of a unique color reference based on LED diodes called the LED Color Generator (LED CG). It is capable of displaying colors in a wide color gamut estimated by chromaticity coordinates of 12 primary colors. The total amount of colors possible to produce is 25512. The biggest advantage is a possibility of displaying colors with desired spectral distribution (with certain approximations) due to multiple primary colors it consists. The average color difference obtained for test colors was found to be ▵E~0.78 for calibration with LED CG. The result is much better and repetitive in comparison with the Macbeth ColorCheckerTM which typically gives ▵E~1.2 and in the best case ▵E~0.83 with specially developed techniques.

  19. Color-symmetric superconductivity in a phenomenological QCD model

    DEFF Research Database (Denmark)

    Bohr, Henrik; Providencia, C.; Providencia, J. da

    2009-01-01

    In this paper, we construct a theory of the NJL type where superconductivity is present, and yet the superconducting state remains, in the average, color symmetric. This shows that the present approach to color superconductivity is consistent with color singletness. Indeed, quarks are free...... in the deconfined phase, but the deconfined phase itself is believed to be a color singlet. The usual description of the color superconducting state violates color singletness. On the other hand, the color superconducting state here proposed is color symmetric in the sense that an arbitrary color rotation leads...

  20. Colorful ESL Test Papers And Spatial Intelligence:

    Directory of Open Access Journals (Sweden)

    Dennis Moradkhan

    2014-11-01

    Full Text Available The purpose of this research was to find out whether introducing color as an element which may appeal to spatially-intelligent candidates affects their performance on ESL grammar tests. 52 participants were given two parallel grammar tests, one in black and white and the other bearing the full spectrum of colors in the natural daylight. In order to identify the candidates with visual-spatial learning style, the participants and their teachers were asked to respond to Visual-Spatial Identifier rating scale. Based on the results, no significant relationship was found between the performance of candidates on the colorful and black and white grammar tests and their visual-spatial intelligence. It was concluded that other variables including the method of applying colors, the type and combination of colors as well as the differential impact of different colors on candidates with different cultural backgrounds needed to be addressed before any conclusions can be drawn about the application of color in language assessment. Keywords: assessment, colorful exam papers, multiple intelligences, spatial intelligence

  1. 7 CFR 29.3066 - Tan color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Tan color. 29.3066 Section 29.3066 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Tan color. A light red-yellow....

  2. Color vision: mice see hue too.

    Science.gov (United States)

    Conway, Bevil R

    2007-06-19

    A transgenic mouse has been generated with three cone types, instead of the normal murine two. Remarkably, some of these mice use the extra cone to make trichromatic color discriminations similar to those that are the basis of human color vision.

  3. Applying daytime colors to multiband nightvision imagery

    NARCIS (Netherlands)

    Toet, A.

    2003-01-01

    We present a method to give (fused) multiband night-time imagery a natural day-time color appearance. For input, the method requires a false color RGB image that is produced by mapping 3 individual bands (or the first 3 principal components) of a multiband nightvision system to the respective channe

  4. 7 CFR 52.778 - Color.

    Science.gov (United States)

    2010-01-01

    ... PROCESSED FRUITS AND VEGETABLES, PROCESSED PRODUCTS THEREOF, AND CERTAIN OTHER PROCESSED FOOD PRODUCTS 1.... (a) (A) classification. Canned red tart pitted cherries that have a good color may be given a score...) (B) classification. Canned red tart pitted cherries that have a reasonably good color may be given...

  5. 7 CFR 52.1006 - Color.

    Science.gov (United States)

    2010-01-01

    ... PROCESSED FRUITS AND VEGETABLES, PROCESSED PRODUCTS THEREOF, AND CERTAIN OTHER PROCESSED FOOD PRODUCTS 1 United States Standards for Grades of Dates Factors of Quality § 52.1006 Color. (a) (A) classification... more than 5 percent by count of dates that are light amber in color. (b) (B) classification. If...

  6. Predicting Color Output of Additive Manufactured Parts

    DEFF Research Database (Denmark)

    Eiríksson, Eyþór Rúnar; Pedersen, David Bue; Aanæs, Henrik

    2015-01-01

    In this paper we address the colorimetric performance of a multicolor additive manufacturing process. A method on how to measure and characterize color performance of said process is presented. Furthermore, a method on predicting the color output is demonstrated, allowing for previsualization...

  7. Perceptual evaluation of color transformed multispectral imagery

    NARCIS (Netherlands)

    Toet, A.; Jong, M.J. de; Hogervorst, M.A.; Hooge, I.T.C.

    2014-01-01

    Color remapping can give multispectral imagery a realistic appearance. We assessed the practical value of this technique in two observer experiments using monochrome intensified (II) and long-wave infrared (IR) imagery, and color daylight (REF) and fused multispectral (CF) imagery. First, we investi

  8. Perceptual evaluation of colorized nighttime imagery

    NARCIS (Netherlands)

    Toet, A.; Jong, M.J. de; Hogervorst, M.A.; Hooge, I.T.C.

    2014-01-01

    We recently presented a color transform that produces fused nighttime imagery with a realistic color appearance (Hogervorst & Toet, 2010, Information Fusion, 11-2, 69-77). To assess the practical value of this transform we performed two experiments in which we compared human scene recognition for mo

  9. The Magic Moment: Creating Color Harmony

    Science.gov (United States)

    Bartges, Dan

    2009-01-01

    If there is a truly magic moment in art class, it must be when a student--of any age--attains a working knowledge of color's core principles. At that point, she or he becomes able to consistently create color harmony in any painting, regardless of the subject matter. From then on, that student gains greater confidence, can paint better pictures…

  10. Cross-cultural color-odor associations

    NARCIS (Netherlands)

    Levitan, C.A.; Ren, J.; Boesveldt, S.; Chan, J.; McKenzie, K.J.; Levin, J.A.; Leong, C.X.; Bosch, van den J.F.

    2014-01-01

    Colors and odors are associated; for instance, people typically match the smell of strawberries to the color pink or red. These associations are forms of crossmodal correspondences. Recently, there has been discussion about the extent to which these correspondences arise for structural reasons (i.e.

  11. Micro-Expression Recognition Using Color Spaces.

    Science.gov (United States)

    Wang, Su-Jing; Yan, Wen-Jing; Li, Xiaobai; Zhao, Guoying; Zhou, Chun-Guang; Fu, Xiaolan; Yang, Minghao; Tao, Jianhua

    2015-12-01

    Micro-expressions are brief involuntary facial expressions that reveal genuine emotions and, thus, help detect lies. Because of their many promising applications, they have attracted the attention of researchers from various fields. Recent research reveals that two perceptual color spaces (CIELab and CIELuv) provide useful information for expression recognition. This paper is an extended version of our International Conference on Pattern Recognition paper, in which we propose a novel color space model, tensor independent color space (TICS), to help recognize micro-expressions. In this paper, we further show that CIELab and CIELuv are also helpful in recognizing micro-expressions, and we indicate why these three color spaces achieve better performance. A micro-expression color video clip is treated as a fourth-order tensor, i.e., a four-dimension array. The first two dimensions are the spatial information, the third is the temporal information, and the fourth is the color information. We transform the fourth dimension from RGB into TICS, in which the color components are as independent as possible. The combination of dynamic texture and independent color components achieves a higher accuracy than does that of RGB. In addition, we define a set of regions of interests (ROIs) based on the facial action coding system and calculated the dynamic texture histograms for each ROI. Experiments are conducted on two micro-expression databases, CASME and CASME 2, and the results show that the performances for TICS, CIELab, and CIELuv are better than those for RGB or gray.

  12. The prior statistics of object colors

    NARCIS (Netherlands)

    Koenderink, J.J.

    2010-01-01

    The prior statistics of object colors is of much interest because extensive statistical investigations of reflectance spectra reveal highly non-uniform structure in color space common to several very different databases. This common structure is due to the visual system rather than to the statistics

  13. COLOR PRESCRIPTION FORM FOR COSMETIC GLOVES

    Science.gov (United States)

    A technique is described for achieving more custom-like coloring of cosmetic gloves. The method involves the use of a color prescription form which...can be used to describe in greater detail the characteristics of those portions of the human hand of greater cosmetic significance.

  14. 7 CFR 29.3509 - Color intensity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color intensity. 29.3509 Section 29.3509 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... colors except green. (See Elements of Quality, § 29.3586.)...

  15. 7 CFR 51.1829 - Well colored.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... good yellow or better ground color predominates over the green color on the entire fruit surface...

  16. 7 CFR 51.647 - Slightly colored.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... aggregate of green color, the portion of the fruit surface which is not discolored shows some yellow color....

  17. Some new aspects of color stereoscopy

    NARCIS (Netherlands)

    Vos, J.J.

    1960-01-01

    By the term color stereoscopy we mean that the color of an object has an influence on its apparent distance in binocular perception. It is usually explained in terms of the chromatic aberration of the eye, together with the eccentric position of the fovea. In this paper we demonstrate that this theo

  18. Samuel Beckett: Color, Letter, and Line.

    Science.gov (United States)

    Conley, Tom

    1985-01-01

    Through a bilingual reading of Beckett's "Mal vu mal dit," the illusion of painted relief for printed letters is created. Colors manifest themselves through the continual process of translation. The French translation adds color to the black and white English text. (DF)

  19. A Software Application to Detect Dental Color

    Directory of Open Access Journals (Sweden)

    Dan SÎMPĂLEAN

    2015-09-01

    Full Text Available Choosing dental color for missing teeth or tooth reconstruction is an important step and it usually raises difficulties for dentists due to a significant amount of subjective factors that can influence the color selection. Dental reconstruction presumes the combination between dentistry and chromatics, thus implying important challenges. Purpose: The aim of this study was to develop and implement a software application for detecting dental color to come to the aid of dentists and largely to remove the inherent subjectiveness of the human vision. Basic Methods: The implemented application was named Color Detection and the application’s source code is written using the C++ language. During application development, for creating the GUI (graphical user interface the wxWidgets 2.8 library it was used. Results: The application displays the average color of the selected area of interest, the reference color from the key collection existent in the program and also the degree of similarity between the original (the selected area of interest and the nearest reference key. This degree of similarity is expressed as a percentage. Conclusions: The Color Detection Program, by eliminating the subjectivity inherent to human sight, can help the dentist to select an appropriate dental color with precision.

  20. 7 CFR 29.2509 - Color symbols.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Color symbols. 29.2509 Section 29.2509 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... types, color symbols are L—light brown, F—medium brown, D—dark brown, M—mixed or variegated...