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| {{two other uses||the city in Vietnam|Huế}}
| | Hi, everybody! My name is Hermine. <br>It is a little about myself: I live in Denmark, my city of Jerslev J. <br>It's called often Eastern or cultural capital of REGION NORDJYLLAND. I've married 3 years ago.<br>I have 2 children - a son (Sarah) and the daughter (Chris). We all like Coloring.<br><br>my web blog [http://stepbrothersfullmovie.blogspot.com/ Step Brothers Full Movie] |
| <!-- {{unreferenced|article|date=December 2006}} -->
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| [[Image:HueScale.svg|thumb|right|360px|Hue in the [[HSL color space|HSB]]/[[HSL color space|HSL]] encodings of [[RGB]]]]
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| [[Image:Hue shift six photoshop.jpg|thumb|An image with the hues cyclically shifted in HSL space]]
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| [[Image:Hue.gif|thumb|The hues in the image of this [[Painted Bunting]] are cyclically rotated over time.]]
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| '''Hue''' is one of the main properties of a [[color]], defined technically (in the [[CIECAM02]] model), as "the degree to which a stimulus can be described
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| as similar to or different from stimuli that are described as [[red]], [[green]], [[blue]], and [[yellow]],"<ref>Mark Fairchild, "Color Appearance Models:
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| CIECAM02 and Beyond." Tutorial slides for IS&T/SID 12th Color Imaging Conference.</ref> (the [[unique hues]]). The other main correlatives of color appearance are [[colorfulness]], chroma, [[Saturation (color theory)|saturation]], [[lightness (color)|lightness]], and [[brightness]].
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| Usually, colors with the same hue are distinguished with adjectives referring to their lightness and/or colorfulness, such as with "light blue", "pastel blue", "vivid blue". Exceptions include [[brown]], which is a dark [[Orange (colour)|orange]],<ref name="Bartleson1976">C J Bartleson, "Brown". ''Color Research and Application,'' '''1''' : 4, p 181-191 (1976).</ref> and [[pink]], a light red with reduced chroma.
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| In [[painting]] [[color theory]], a '''hue''' refers to a ''pure'' color—one without [[Tints and shades|tint or shade]] (added white or black [[pigment]], respectively).<ref>{{cite web|url=http://creativecurio.com/2008/05/the-color-wheel-and-color-theory/ |title=The Color Wheel and Color Theory |publisher=Creative Curio |date=2008-05-16 |accessdate=2011-06-09}}</ref> A hue is an element of the [[color wheel]]. Hues are first processed in the [[Human brain|brain]] in areas in the extended V4 called [[glob (visual system)|glob]]s.<ref name="Conway07">{{cite journal | doi = 10.1016/j.neuron.2007.10.008 | last1 = Conway | first1 = BR | last2 = Moeller | first2 = S | last3 = Tsao | first3 = DY. | year = 2007 | title = Specialized color modules in macaque extrastriate cortex | url = | journal = Neuron | volume = 56 | issue = 3| pages = 560–73 | pmid = 17988638 }}</ref><ref name="Conway">{{cite journal | last1 = Conway | first1 = BR | last2 = Tsao | first2 = DY | title = Color-tuned neurons are spatially clustered according to color preference within alert macaque posterior inferior temporal cortex | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 106 | issue = 42 | pages = 18034–9 | year = 2009 | pmid = 19805195 | pmc = 2764907 | doi = 10.1073/pnas.0810943106 }}</ref>
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| == Computing hue ==
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| In [[opponent process|opponent color spaces]] in which two of the axes are perceptually orthogonal to lightness, such as the CIE 1976 (''L''*, ''a''*, ''b''*) ([[CIELAB]]) and 1976 (''L''*, ''u''*, ''v''*) ([[CIELUV]]) color spaces, hue may be computed together with chroma by converting these coordinates from [[rectangular coordinates|rectangular]] form to [[polar coordinates|polar]] form. Hue is the angular component of the polar representation, while chroma is the radial component.
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| Specifically, in CIELAB:<ref name="CIE1986">''Colorimetry,'' second edition: CIE Publication 15.2. Vienna: Bureau Central of the CIE, 1986.</ref>
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| :<math>h_{ab} = \mathrm{atan2}(b^*, a^*)\;</math>
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| while, analogously, in CIELUV:<ref name = "CIE1986"/>
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| :<math>h_{uv} = \mathrm{atan2}(v^*, u^*) = \mathrm{atan2}(v', u')\;</math>
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| Where, [[atan2]] is a two-argument inverse tangent.
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| === Computing hue from RGB ===
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| Preucil<ref name = "Preucil1953">Frank Preucil, "Color Hue and Ink Transfer … Their Relation to Perfect Reproduction, ''TAGA Proceedings,'' p 102-110 (1953).</ref> describes a color hexagon, similar to a trilinear plot described by Evans, Hanson, and Brewer,<ref name = "Evans1953">Ralph Merrill Evans, W T Hanson, and W Lyle Brewer, ''Principles of Color Photography.'' New York: Wiley, 1953</ref> which may be used to compute hue from [[RGB]]. To place [[red]] at 0°, [[green]] at 120°, and [[blue]] at 240°.
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| :<math> h_{rgb} = \mathrm{atan2}\left( \sqrt{3} \cdot (G - B), 2 \cdot R - G - B \right) </math>
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| Equivalently, one may solve:
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| :<math> \tan( h_{rgb}) = \frac{\sqrt{3}\cdot (G - B)}{2\cdot R - G - B} </math>
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| Preucil used a polar plot, which he termed a color circle.<ref name = "Preucil1953"/> Using R, G, and B, one may compute hue angle using the following scheme: determine which of the six possible orderings of R, G, and B prevail, then apply the formula given in the table below.
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| [[Image:HSV cone.jpg|thumb|HSV color space as a conical object]]
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| [[Image:HSV-RGB-comparison.svg|thumb|right|An illustration of the relationship between the "hue" of colors with maximal saturation in HSV and HSL with their corresponding RGB coordinates.]]
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| {| class="wikitable" style="background:white;"
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| |-
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| ! Ordering
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| ! Hue Region
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| ! Formula
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| |-
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| | <math>R \ge G \ge B</math>
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| | Red-Yellow
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| | <math>h_{Preucil\ circle} = 60^{\circ} \cdot \frac{G - B}{R - B}</math>
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| |-
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| | <math>G > R \ge B</math>
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| | Yellow-Green
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| | <math>h_{Preucil\ circle} = 60^{\circ} \cdot \left( 2 - \frac{R - B}{G - B}\right)</math>
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| |-
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| | <math>G \ge B > R</math>
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| | Green-Cyan
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| | <math>h_{Preucil\ circle} = 60^{\circ} \cdot \left( 2 + \frac{B - R}{G - R}\right)</math>
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| |-
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| | <math>\ B > G > R\ </math>
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| | Cyan-Blue
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| | <math>h_{Preucil\ circle} = 60^{\circ} \cdot \left( 4 - \frac{G - R}{B - R}\right)</math>
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| |-
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| | <math>B > R \ge G</math>
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| | Blue-Magenta
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| | <math>h_{Preucil\ circle} = 60^{\circ} \cdot \left( 4 + \frac{R - G}{B - G}\right)</math>
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| |-
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| | <math>R \ge B > G</math>
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| | Magenta-Red
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| | <math>h_{Preucil\ circle} = 60^{\circ} \cdot \left( 6 - \frac{B - G}{R - G}\right)</math>
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| |}
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| Note that in each case the formula contains the fraction <math>\frac{M - L}{H - L}</math>, where H is the highest of R, G, and B; L is the lowest, and M is the mid one between the other two. This is referred to as the Preucil Hue Error, and was used in the computation of mask strength in photomechanical color reproduction.<ref name = "Southworth">Miles Southworth, ''Color Separation Techniques,'' second edition. Livonia, New York: Graphic Arts Publishing, 1979</ref>
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| Hue angles computed for the Preucil circle agree with the hue angle computed for the Preucil Hexagon at integer multiples of 30 degrees (red, yellow, green, cyan, blue, magenta, and the colors mid-way between contiguous pairs) and differ by approximately 1.2 degrees at odd integer multiples of 15 degrees (based on the circle formula), the maximum divergence between the two.
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| The process of converting an RGB color into an [[HSL color space]] or [[HSV color space]] is usually based on a 6-piece piecewise mapping, treating the HSV cone as a hexacone, or the HSL double cone as a double hexacone.<ref>{{cite book | title = Computer Graphics and Geometric Modelling v. 1: Implementation and Algorithms | author = Max K. Agoston | isbn = 1-85233-818-0 | publisher = Springer | year = 2004 | url = http://books.google.com/?id=fGX8yC-4vXUC&pg=PA301&lpg=PA301&dq=hsv++hue+rgb#PPA304,M1 | pages = 301–304}}</ref> The formulae used are those in the table above.
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| == Specialized hues ==
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| The hues exhibited by [[caramel color]]ings and [[beer]]s are fairly limited in range. The [[Linner hue index]] is used to quantify the hue of such products.
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| == Usage in art ==
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| Manufacturers of pigments use the word hue e.g. 'Cadmium Yellow (hue)' to indicate that the original pigmentation ingredient, often toxic, has been replaced by safer (or cheaper) alternatives whilst retaining the hue of the original. Replacements are often used for [[chromium]], [[cadmium]] and [[alizarin]].
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| == Hue vs. dominant wavelength ==
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| [[Dominant wavelength]] (or sometimes equivalent wavelength) is a physical analog to the perceptual attribute hue. On a [[chromaticity diagram]], a line is drawn from a [[white point]] through the coordinates of the color in question, until it intersects the [[CIE 1931 color space#The CIE xy chromaticity diagram|spectral locus]]. The wavelength at which the line intersects the spectrum locus is identified as the color's [[dominant wavelength]] if the point is on the same side of the white point as the spectral locus, and as the color's [[complementary wavelength]] if the point is on the opposite side.<ref name = "Judd1976">Deane B Judd and Günter Wyszecki, ''Color in Business, Science, and Industry.'' New York: Wiley, 1976.</ref>
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| == Hue difference: <math>\Delta h</math> or <math>\Delta H^*</math>? ==
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| There are two main ways in which hue difference is quantified. The first is the simple difference between the two hue angles. The symbol for this expression of hue difference is <math>\Delta h_{ab}</math> in CIELAB and <math>\Delta h_{uv}</math> in CIELUV. The other is computed as the residual total color difference after Lightness and Chroma differences have been accounted for; its symbol is <math>\Delta H^*_{ab}</math> in CIELAB and <math>\Delta H^*_{uv}</math> in CIELUV.
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| == Names and other notations for hues ==
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| There exists some correspondence, more or less precise, between hue values and [[color term]]s (names). One approach in color science is to use traditional color terms but try to give them more precise definitions. See [[spectral color #Table of spectral or near-spectral colors]] for names of highly saturated colors with the hue from ≈ 0° (red) up to ≈ 275° (violet), and [[line of purples #Table of highly-saturated purple colors]] for color terms of the remaining part of the color wheel.
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| Alternative approach is to use a systematic notation. It can be a standard [[angle]] notation for certain color model such as HSL/HSV mentioned above, [[CIELUV]], or [[CIECAM02]]. Alphanumeric notations such as of [[Munsell color system]], [[Natural Color System|NCS]], and [[Pantone Matching System]] are also used.
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| == See also ==
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| *[[Lightness (color)]]
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| *[[Chromaticity]]
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| *[[Munsell color system]]
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| *[[Bezold–Brücke shift]]
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| == References ==
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| {{Reflist}}
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| == External links ==
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| *[http://gimps.de/en/tutorials/gimp/picture-photo-image/improve-colors/ Editing of hue in photography]
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| [[Category:Color]]
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| {{Color topics}}
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Hi, everybody! My name is Hermine.
It is a little about myself: I live in Denmark, my city of Jerslev J.
It's called often Eastern or cultural capital of REGION NORDJYLLAND. I've married 3 years ago.
I have 2 children - a son (Sarah) and the daughter (Chris). We all like Coloring.
my web blog Step Brothers Full Movie