Editing Video (section)

===Color model and depth===
[[Image:YUV UV plane.svg|thumb|200px|Example of U-V color plane, Y value=0.5]]

The [[color model]] uses the video color representation and maps encoded color values to visible colors reproduced by the system. There are several such representations in common use: typically, [[YIQ]] is used in NTSC television, [[YUV]] is used in PAL television, [[YDbDr]] is used by SECAM television, and [[YCbCr]] is used for digital video.<ref name=":4">{{Cite book |last1=Li |first1=Ze-Nian |url=https://www.worldcat.org/oclc/1243420273 |title=Fundamentals of multimedia |last2=Drew |first2=Mark S. |last3=Liu |first3=Jiangchun |date=2021 |publisher=[[Springer Publishing|Springer]] |isbn=978-3-030-62124-7 |edition=3rd |location=Cham, Switzerland |pages=108–117 |oclc=1243420273 |access-date=August 25, 2022 |archive-date=August 25, 2022 |archive-url=https://web.archive.org/web/20220825123925/https://www.worldcat.org/title/1243420273 |url-status=live }}</ref><ref name=":5">{{Cite book |last=Banerjee |first=Sreeparna |url=https://www.worldcat.org/oclc/1098279086 |title=Elements of multimedia |date=2019 |publisher=CRC Press |isbn=978-0-429-43320-7 |location=Boca Raton |chapter=Video in Multimedia |oclc=1098279086 |access-date=August 25, 2022 |archive-date=August 25, 2022 |archive-url=https://web.archive.org/web/20220825123925/https://www.worldcat.org/title/1098279086 |url-status=live }}</ref>

The number of distinct colors a pixel can represent depends on the [[color depth]] expressed in the number of bits per pixel. A common way to reduce the amount of data required in digital video is by [[chroma subsampling]] (e.g., 4:4:4, 4:2:2, etc.). Because the human eye is less sensitive to details in color than brightness, the luminance data for all pixels is maintained, while the chrominance data is averaged for a number of pixels in a block, and the same value is used for all of them. For example, this results in a 50% reduction in chrominance data using 2-pixel blocks (4:2:2) or 75% using 4-pixel blocks (4:2:0). This process does not reduce the number of possible color values that can be displayed, but it reduces the number of distinct points at which the color changes.<ref name=":2" /><ref name=":4" /><ref name=":5" />