The objective of this study was to evaluate the effect of two bleaching agents (10% and 35% hydrogen peroxide) on the color stability and surface roughness of two composites, one nanohybrid and one nanoparticle. Specimens were polished, aged, stained, bleached and polished again. The action of the bleaching agents on the composites was analyzed using a profilometer (surface roughness) and a spe...

It is widely believed that the cortical mechanisms of color vision are monocular because stereopsis is poor for isoluminant patterns. By measuring and comparing the chromatic tuning of binocular and monocular neurons in cortical areas V1 and V2 of macaque, we show that this is not the case. Not only are many color-preferring cells in early visual cortex well-driven binocularly, but their color ...

In this study, we present several demonstrations of color averaging between luminance boundaries. In each of the demonstrations, different black outlines are superimposed on one and the same colored surface. Whereas perception without these outlines comprises a blurry colored gradient, superimposing the outlines leads to a much clearer binary color percept, with different colors perceived on ea...

How do the colors of surfaces seen through fog depend on the chromatic properties of the fog? Prior work (e.g. Chen and D'Zmura, 1998 Perception 27 595-608) shows that the colors of surfaces seen through a transparent filter can be described by a convergence model. The convergence model takes into account color shift and change in contrast. Whether the convergence model can also be applied to f...

The analysis of skin color with makeup is needed to examine the effect of makeup to human skin. Foundation is cosmetics to cover undesirable color on skin and gives basic color to skin. It is important evaluate a change of skin color by the foundation. The present paper modeled the optics of skin with foundation makeup by two layers. Then, the surface spectrum of skin with foundation makeup is ...

This paper proposed a detection method of rice process quality using the color and BP neural network. A rice process quality detection device based on computer vision technology was designed to get rice image, a circle of the radius R in the abdomen of the rice was determined as a color feature extraction area, and which was divided into five concentric sub-domains by the average area, the aver...

ÐThe observed image texture for a rough surface has a complex dependence on the illumination and viewing angles due to effects such as foreshortening, local shading, interreflections, and the shadowing and occlusion of surface elements. We introduce the dimensionality surface as a representation for the visual complexity of a material sample. The dimensionality surface defines the number of bas...

The purpose of color constancy algorithms is to estimate the illumination color reflected from an object and then eliminate it, making the color of the object appearance identical to the object actual color. To accomplish the purpose, we have developed a color constancy algorithm which is extended from Finlayson et al’s algorithm. By combining varying illumination constraint, Planckian locus wh...

This paper describes a color classification technique for the color subspaces definition based in 3D reconstruction approaches. These color subspaces use implicit functions to create a bounding surface that will fit a set of characteristic color samples to define a particular color. The implicit subspace reconstruction allow to define clusters of arbitrary shape for a better approximation of th...

Contrasting theories of visual attention have emphasized selection by spatial location, individual features, and whole objects. We used functional magnetic resonance imaging to ask whether and how attention to one feature of an object spreads to other features of the same object. Subjects viewed two spatially superimposed surfaces of random dots that were segregated by distinct color-motion con...