YUV


YUV

  • YUV –  The term YUV almost always refers to one particular color space named Y’CbCr, The YUV color model imitates a human vision  i.e humans are able to recognize (discern) the contents of a color RGB (Red, Green, Blue) image.
  •  In YUV,  the Y (Y’) determines the brightness of the color (referred as luminance or luma) the prime symbol (‘) is used to differentiate luma from a closely related value, which is designated Y. Luminance is derived from linear RGB values, whereas luma is derived from non-linear (gamma-corrected) RGB values. Luminance is a closer measure of true brightness but luma is more practical to use for technical reasons. Y ranges from 0 to 1 (or 0 to 255 in digital formats).
  • While the U and V components determine the color itself (the chroma). while U and V range from -0.5 to 0.5 (or -128 to 127 in signed digital form, or 0 to 255 in unsigned form).
  • U and V provide color information and are “color difference” signals of blue minus luma (B-Y) and red minus luma (R-Y). Through a process called “color space conversion,” the video camera converts the RGB data captured by its sensors into either composite analog signals (YUV) or component versions (analog YPbPr or digital YCbCr). For rendering on screen, all these color spaces must be converted back again to RGB by the TV or display system.
  • YCbCr as a color space for digital television systems.
  • Individual color components of YCbCr color space are luma Y, chroma Cb and chroma Cr. Chroma Cb corresponds to the U color component, and chroma Cr corresponds to the V component of a general YUV color space.
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Categories: Color Science
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