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Gamut (horse)
In color reproduction and colorimetry, a gamut, or color gamut , is a convex set containing the colors that can be accurately represented, i.e. reproduced by an output device (e.g. printer or display) or measured by an input device (e.g. camera or visual system). Devices with a larger gamut can represent more colors. Similarly, gamut may also refer to the colors within a defined color space, which is not linked to a specific device. A trichromatic gamut is often visualized as a color triangle. A less common usage defines gamut as the subset of colors contained within an image, scene or video. Introduction The term ''gamut'' was adopted from the field of music, where in middle age Latin "gamut" meant the entire range of musical notes of which musical melodies are composed; Shakespeare's use of the term in '' The Taming of the Shrew'' is sometimes attributed to the author / musician Thomas Morley. In the 1850s, the term was applied to a range of colors or hue, for exa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtractive Color
Subtractive color or subtractive color mixing predicts the spectral power distribution of light after it passes through successive layers of partially absorbing media. This idealized model is the essential principle of how dyes and inks are used in color printing and photography where the perception of color is elicited after white light passes through microscopic "stacks" of partially absorbing media allowing some wavelengths of light to reach the eye and not others. Process The subtractive color mixing model predicts the resultant spectral power distribution of light filtered through overlaid partially absorbing materials on a reflecting or transparent surface. Each layer partially absorbs some wavelengths of light from the illumination spectrum while letting others pass through, resulting in a colored appearance. The resultant spectral power distribution is predicted by sequentially taking the product of the spectral power distributions of the incoming light and transmis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectral Sensitivity
Spectral sensitivity is the relative efficiency of detection, of light or other signal, as a function of the frequency or wavelength of the signal. In visual neuroscience, spectral sensitivity is used to describe the different characteristics of the photopigments in the rod cells and cone cells in the retina of the eye. It is known that the rod cells are more suited to scotopic vision and cone cells to photopic vision, and that they differ in their sensitivity to different wavelengths of light. It has been established that the maximum spectral sensitivity of the human eye under daylight conditions is at a wavelength of 555 nm, while at night the peak shifts to 507 nm. In photography, film and sensors are often described in terms of their spectral sensitivity, to supplement their characteristic curves that describe their responsivity. A database of camera spectral sensitivity is created and its space analyzed. For X-ray films, the spectral sensitivity is chosen to b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Color Perception
Color vision, a feature of visual perception, is an ability to perceive differences between light composed of different wavelengths (i.e., different spectral power distributions) independently of light intensity. Color perception is a part of the larger visual system and is mediated by a complex process between neurons that begins with differential stimulation of different types of photoreceptors by light entering the eye. Those photoreceptors then emit outputs that are propagated through many layers of neurons and then ultimately to the brain. Color vision is found in many animals and is mediated by similar underlying mechanisms with common types of biological molecules and a complex history of evolution in different animal taxa. In primates, color vision may have evolved under selective pressure for a variety of visual tasks including the foraging for nutritious young leaves, ripe fruit, and flowers, as well as detecting predator camouflage and emotional states in other prim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICC Profile
In color management, an ICC profile is a set of data that characterizes a color input or output device, or a color space, according to standards promulgated by the International Color Consortium (ICC). Profiles describe the color attributes of a particular device or viewing requirement by defining a mapping between the device source or target color space and a ''profile connection space'' (PCS). This PCS is either CIELAB (L*a*b*) or CIEXYZ. Mappings may be specified using tables, to which interpolation is applied, or through a series of parameters for transformations. Every device that captures or displays color can be profiled. Some manufacturers provide profiles for their products, and there are several products that allow an end-user to generate their own color profiles, typically through the use of a tristimulus colorimeter or a spectrophotometer (sometimes called a spectrocolorimeter). The ICC defines the format precisely but does not define algorithms or processing det ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adobe RGB
The Adobe RGB (1998) color space or opRGB is a color space developed by Adobe Systems, Inc. in 1998. It was designed to encompass most of the colors achievable on CMYK color printers, but by using RGB primary colors on a device such as a computer display. The Adobe RGB (1998) color space encompasses roughly 50% of the visible colors specified by the CIELAB color space – improving upon the gamut of the sRGB color space, primarily in cyan-green hues. It was subsequently standardized by the IEC as IEC 61966-2-5:1999 with a name opRGB (optional RGB color space) and is used in HDMI. Historical background Beginning in 1997, Adobe Systems was looking into creating ICC profiles that its consumers could use in conjunction with Photoshop's new color management features. Since not many applications at the time had any ICC color management, most operating systems did not ship with useful profiles. Lead developer of Photoshop, Thomas Knoll decided to build an ICC profile ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SRGB
sRGB is a standard RGB (red, green, blue) color space that HP and Microsoft created cooperatively in 1996 to use on monitors, printers, and the World Wide Web. It was subsequently standardized by the International Electrotechnical Commission (IEC) as IEC 61966-2-1:1999. sRGB is the current defined standard colorspace for the web, and it is usually the assumed colorspace for images that are neither tagged for a colorspace nor have an embedded color profile. sRGB essentially codifies the display specifications for the computer monitors in use at that time, which greatly aided its acceptance. sRGB uses the same color primaries and white point as ITU-R BT.709 standard for HDTV, a transfer function (or gamma) compatible with the era's CRT displays, and a viewing environment designed to match typical home and office viewing conditions. An amendment of the IEC 61966-2-1 standard document that defines sRGB includes the definition of a number of variants including sYCC, which i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burned (image)
An image is said to be burned or burnt when its original gamut considerably exceeds the target gamut, or when the result of processing considerably exceeds the image's gamut, resulting in clipping.Langford, Fox, and Smith. ''Langford's Basic Photography'', p. 354 Colloquially, an image is burned when it contains uniform blobs of color, black, or white where there should actually be detail. All media for storing or capturing images, both analog and digital, are capable of storing only a limited number of color hues, and are bound to a certain gamut. Squeezing an image with a given gamut into a medium with a smaller gamut is done either by adapting the whole range of colors to the new gamut, or by ''trimming'' the colors out of gamut. Trimming colors at the extremes results in burning the image. While converting and capturing images is usually a "smart" process that tries to accommodate the entire gamut of the original into the target color space A color space is a specifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CMYK Color Model
The CMYK color model (also known as process color, or four color) is a subtractive color model, based on the CMY color model, used in color printing, and is also used to describe the printing process itself. The abbreviation ''CMYK'' refers to the four ink plates used: cyan, magenta, yellow, and key (black). The CMYK model works by partially or entirely masking colors on a lighter, usually white, background. The ink reduces the light that would otherwise be reflected. Such a model is called ''subtractive'' because inks "subtract" the colors red, green and blue from white light. White light minus red leaves cyan, white light minus green leaves magenta, and white light minus blue leaves yellow. In additive color models, such as RGB, white is the "additive" combination of all primary colored lights, black is the absence of light. In the CMYK model, it is the opposite: white is the natural color of the paper or other background, black results from a full combination of c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RYB Color Model
RYB (an abbreviation of red–yellow–blue) is a subtractive color model used in art and applied design in which red, yellow, and blue pigments are considered primary colors. Under traditional color theory, (which some artists see as the “correct theory” whilst others use modern color theory yminstead) this set of primary colors was advocated by Moses Harris, Michel Eugène Chevreul, Johannes Itten and Josef Albers, and applied by countless artists and designers. The RYB color model underpinned the color curriculum of the Bauhaus, Ulm School of Design and numerous art and design schools that were influenced by the Bauhaus, including the IIT Institute of Design (founded as the New Bauhaus), Black Mountain College, Design Department Yale University, the Shillito Design School, Sydney, and Parsons School of Design, New York. In this context, the term ''primary color'' refers to three exemplar colors (red, yellow, and blue) as opposed to specific pigments. As illustrated, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Color
A set of primary colors or primary colours (see spelling differences) consists of colorants or colored lights that can be mixed in varying amounts to produce a gamut of colors. This is the essential method used to create the perception of a broad range of colors in, e.g., electronic displays, color printing, and paintings. Perceptions associated with a given combination of primary colors can be predicted by an appropriate mixing model (e.g., additive, subtractive) that reflects the physics of how light interacts with physical media, and ultimately the retina. Primary colors can also be conceptual (not necessarily real), either as additive mathematical elements of a color space or as irreducible phenomenological categories in domains such as psychology and philosophy. Color space primaries are precisely defined and empirically rooted in psychophysical colorimetry experiments which are foundational for understanding color vision. Primaries of some color spaces are ''com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectral Power Distribution
In radiometry, photometry, and color science, a spectral power distribution (SPD) measurement describes the power per unit area per unit wavelength of an illumination ( radiant exitance). More generally, the term ''spectral power distribution'' can refer to the concentration, as a function of wavelength, of any radiometric or photometric quantity (e.g. radiant energy, radiant flux, radiant intensity, radiance, irradiance, radiant exitance, radiosity, luminance, luminous flux, luminous intensity, illuminance, luminous emittance). Knowledge of the SPD is crucial for optical-sensor system applications. Optical properties such as transmittance, reflectivity, and absorbance as well as the sensor response are typically dependent on the incident wavelength. Physics Mathematically, for the spectral power distribution of a radiant exitance or irradiance one may write: : M(\lambda)=\frac\approx\frac where ''M''(''λ'') is the spectral irradiance (or exitance) of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
