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YDbDr, sometimes written ${\displaystyle YD_{B}D_{R}}$, is the colour space used in the SECAM (adopted in France and some countries of the former Eastern Bloc) analog colour television broadcasting standard. It is very close to YUV (used on the PAL system) and its related colour spaces such as YIQ (used on the NTSC system), YPbPr and YCbCr.

${\displaystyle YD_{B}D_{R}}$ is composed of three components: ${\displaystyle Y}$, ${\displaystyle D_{B}}$ and ${\displaystyle D_{R}}$. ${\displaystyle Y}$ is the luminance, ${\displaystyle D_{B}}$ and ${\displaystyle D_{R}}$ are the chrominance components, representing the red and blue colour differences.

Formulas

The three component signals are created from an original ${\displaystyle RGB}$ (red, green and blue) source. The weighted values of ${\displaystyle R}$, ${\displaystyle G}$ and ${\displaystyle B}$ are added together to produce a single ${\displaystyle Y}$ signal, representing the overall brightness, or luminance, of that spot. The ${\displaystyle D_{B}}$ signal is then created by subtracting the ${\displaystyle Y}$ from the blue signal of the original ${\displaystyle RGB}$, and then scaling; and ${\displaystyle D_{R}}$ by subtracting the ${\displaystyle Y}$ from the red, and then scaling by a different factor.

These formulae approximate the conversion between the RGB colour space and ${\displaystyle YD_{B}D_{R}}$.

${\displaystyle {\begin{aligned}R,G,B,Y&\in \left\\D_{B},D_{R}&\in \left\end{aligned}}}$

From RGB to YDbDr:

${\displaystyle {\begin{aligned}Y&=+0.299R+0.587G+0.114B\\D_{B}&=-0.450R-0.883G+1.333B\\D_{R}&=-1.333R+1.116G+0.217B\\{\begin{bmatrix}Y\\D_{B}\\D_{R}\end{bmatrix}}&={\begin{bmatrix}0.299&0.587&0.114\\-0.450&-0.883&1.333\\-1.333&1.116&0.217\end{bmatrix}}{\begin{bmatrix}R\\G\\B\end{bmatrix}}\end{aligned}}}$

From YDbDr to RGB:

${\displaystyle {\begin{aligned}R&=Y+0.000092303716148D_{B}-0.525912630661865D_{R}\\G&=Y-0.129132898890509D_{B}+0.267899328207599D_{R}\\B&=Y+0.664679059978955D_{B}-0.000079202543533D_{R}\\{\begin{bmatrix}R\\G\\B\end{bmatrix}}&={\begin{bmatrix}1&0.000092303716148&-0.525912630661865\\1&-0.129132898890509&0.267899328207599\\1&0.664679059978955&-0.000079202543533\end{bmatrix}}{\begin{bmatrix}Y\\D_{B}\\D_{R}\end{bmatrix}}\end{aligned}}}$

You may note that the ${\displaystyle Y}$ component of ${\displaystyle YD_{B}D_{R}}$ is the same as the ${\displaystyle Y}$ component of ${\displaystyle Y}$${\displaystyle U}$${\displaystyle V}$. ${\displaystyle D_{B}}$ and ${\displaystyle D_{R}}$ are related to the ${\displaystyle U}$ and ${\displaystyle V}$ components of the YUV colour space as follows:

${\displaystyle {\begin{aligned}D_{B}&=+3.059U\\D_{R}&=-2.169V\end{aligned}}}$

See also

• YUV - related colour system

References

1. Issues in Electronic Circuits, Devices, and Materials: 2011 Edition. ScholarlyEditions. 2012-01-09. p. 1146. ISBN 978-1-4649-6373-5.
2. Recommendation ITU-R BT.470-6 - Conventional Television Systems (PDF). ITU-R. 1998.
3. Shi, Yun-Qing; Sun, Huifang (2019-03-07). Image and Video Compression for Multimedia Engineering: Fundamentals, Algorithms, and Standards, Third Edition. CRC Press. ISBN 978-1-351-57864-6.
4. Dorf, Richard C. (2018-10-03). Circuits, Signals, and Speech and Image Processing. CRC Press. ISBN 978-1-4200-0308-6.
5. Hoang, Dzung Tien; Vitter, Jeffrey Scott (2002-02-21). Efficient Algorithms for MPEG Video Compression. Wiley. ISBN 978-0-471-37942-3.
6. Shum, Heung-Yeung; Chan, Shing-Chow; Kang, Sing Bing (2008-05-26). Image-Based Rendering. Springer Science & Business Media. ISBN 978-0-387-32668-9.
7. ASC, David Stump (2021-11-18). Digital Cinematography: Fundamentals, Tools, Techniques, and Workflows. Routledge. ISBN 978-0-429-88901-1.

• Shi, Yun Q. and Sun, Huifang Image and Video Compression for Multimedia Engineering, CRC Press, 2000 ISBN 0-8493-3491-8

v t e Color space
List of color spaces Color models
CAM	CIECAM02 iCAM CAM16 CIECAM16
CIE	XYZ (1931) RGB (1931) YUV (1960) UVW (1964) CIELAB (1976) CIELUV (1976) CIECAM02 CIECAM16
RGB	RGB color spaces sRGB rg chromaticity Adobe Wide-gamut ProPhoto scRGB DCI-P3 Rec. 601 SMPTE 240M/"C" Rec. 709 Rec. 2020 Rec. 2100
Y′UV	YUV PAL YDbDr SECAM YIQ NTSC YCbCr Rec. 601 Rec. 709 Rec. 2020 Rec. 2100 ICtCp Rec. 2100 YPbPr MAC xvYCC YCoCg
Other	CcMmYK CMYK ColorADD Coloroid LMS Hexachrome HSL, HSV HCL Imaginary color Oklab OSA-UCS PCCS RG RYB HWB YJK TSL
Color systems and standards	ACES ANPA Colour Index International CI list of dyes DIC Federal Standard 595 HKS ICC profile ISCC–NBS Munsell NCS Ostwald Pantone RAL list JIS Z8102 [ja]
For the vision capacities of organisms or machines, see  Color vision.

• Color space