查看“︁YCbCr”︁的源代码

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[[File:Barns grand tetons YCbCr separation.jpg|thumb|一個完整的彩色影像和一個彩色影像只有Y成份的圖、只有Cb成份的圖、和只有Cr成份的圖。只有Y成份的圖基本上就是彩色影像的灰階版本。that the white snow is represented as a middle value in both Cr and Cb; that the brown barn is represented by weak Cb and strong Cr; that the green grass is represented by weak Cb and weak Cr; and that the blue sky is represented by strong Cb and weak Cr.]]

YCbCr或Y'CbCr，是[[色彩空間]]的一種，通常會用于影片中的影像連續處理，或是數位攝影系統中。Y'和Y是不同的，Y是[[流明]]（[[luminance]]），而Y'表示光的濃度且為非線性，使用[[伽玛校正|伽馬修正]]（gamma correction）編碼處理，而Cb和Cr則為藍色和紅色的濃度偏移量。

'''YCbCr'''不是一種[[絕對色彩空間]]，是[[YUV]]壓縮和偏移的版本。YCbCr的Y與YUV中的Y含义一致，Cb和Cr與UV同样都指色彩，Cb指蓝色色度，Cr指红色色度。在应用上很广泛，JPEG、MPEG、DVD、[[攝影機]]、[[數位電視]]等皆採此一格式。因此一般俗稱的YUV大多是指YCbCr。

'''Y'CbCr'''同樣不是一種絕對的色彩空間，是一種針對[[RGB]]資訊所做的編碼。真正的顏色顯示是根據實際RGB色盤（[[colorant]]）來決定。因此Y'CbCr所表示的值只有在標準RGB色盤或是ICC數據（[[ICC Profile|ICC profile]]）有提供的時候才能計算。

YCbCr格式有：
*4∶4∶4
*4∶2∶2
*4∶1∶1
*4∶2∶0

== 名稱 ==
YCbCr有時會稱為YCC. Y'CbCr在[[色差端子]]中也常被稱為YPbPr。

== 技術細節 ==
Y'CbCr訊號（prior to scaling and offsets to place the signals into digital form）被稱為[[YPbPr]]，而且產生時必須合乎gamma-adjusted [[RGB]] source有二個不同的常數Kb和Kr如下：

 YPbPr (analog version of Y'CbCr) from R'G'B'
----
 Y' =  Kr * R'        + (1 - Kr - Kb) * G' + Kb * B'
 Pb = 0.5 * (B' - Y') / (1 - Kb)
 Pr = 0.5 * (R' - Y') / (1 - Kr)
 ....................................................
 R', G', B' in [0; 1]
 Y' in [0; 1]
 Pb in [-0.5; 0.5]
 Pr in [-0.5; 0.5]

<br />
<math>Y' =  Kr * R' + (1 - Kr - Kb) * G' + Kb * B' \,</math><br /><br />
<math>Pb =\frac12 * \frac{B' - Y'}{1 - Kb}</math><br /><br />
<math>Pr =\frac12 * \frac{R' - Y'}{1 - Kr}</math><br /><br />

where Kb and Kr are ordinarily derived from the definition of the corresponding RGB space. (The equivalent [[matrix (mathematics)|matrix]] manipulation is often referred to as the "color matrix.")

== 外部連結 ==
* [http://www.poynton.com/ColorFAQ.html Charles Poynton - Color FAQ] {{Wayback|url=http://www.poynton.com/ColorFAQ.html |date=20110409213505 }}
* [http://www.poynton.com/Poynton-video-eng.html Charles Poynton - Video engineering] {{Wayback|url=http://www.poynton.com/Poynton-video-eng.html |date=20170707001443 }}
* [https://web.archive.org/web/20090111035713/http://www.dvd-replica.com/DVD/colorrgb2.php YCrCb to RGB converter]
* [https://web.archive.org/web/20081207014820/http://www.couleur.org/index.php?page=transformations#YCbCr Color Space Visualization]
* [http://www.pcmag.com/encyclopedia_term/0,2542,t=YCbCr&i=55147,00.asp PC Magazine Encyclopedia: YCbCr] {{Wayback|url=http://www.pcmag.com/encyclopedia_term/0%2C2542%2Ct%3DYCbCr%26i%3D55147%2C00.asp |date=20130308143046 }}

{{色彩空間}}

[[Category:色彩空间]]