YDbDr

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An image along with its
Y
{\displaystyle Y}
,
D
B
{\displaystyle D_{B}}
and
D
R
{\displaystyle D_{R}}
components. YDbDr components.jpg
An image along with its , and components.

YDbDr, sometimes written , is the colour space [1] used in the SECAM (adopted in France and some countries of the former Eastern Bloc) analog colour television broadcasting standard. [2] [3] [4] 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. [5] [6]

Contents

is composed of three components: , and . is the luminance, and are the chrominance components, representing the red and blue colour differences. [7]

Formulas

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

These formulae approximate the conversion between the RGB colour space and .

From RGB to YDbDr:

From YDbDr to RGB:

You may note that the component of is the same as the component of . and are related to the and components of the YUV colour space as follows:

See also

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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.