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The scope of the terms Y′UV, YUV, YCbCr, YPbPr, etc., is sometimes ambiguous and overlapping. Y′UV is the separation used in PAL. YDbDr is the format used in SECAM and PAL-N, unusually based on non-gamma-corrected (linear) RGB, making the Y component true luminance. Y′IQ is the format used in NTSC television.
Huffyuv (or HuffYUV) is a lossless video codec created by Ben Rudiak-Gould which is meant to replace uncompressed YCbCr as a video capture format. The codec can also compress in the RGB color space. "Lossless" means that the output from the decompressor is bit-for-bit identical with the original input to the compressor.
YCbCr is sometimes abbreviated to YCC.Typically the terms Y′CbCr, YCbCr, YPbPr and YUV are used interchangeably, leading to some confusion. The main difference is that YPbPr is used with analog images and YCbCr with digital images, leading to different scaling values for U max and V max (in YCbCr both are ) when converting to/from YUV.
For example, applying a histogram equalization directly to the channels in an RGB image would alter the color balance of the image. Instead, the histogram equalization is applied to the Y channel of the YIQ or YUV representation of the image, which only normalizes the brightness levels of the image.
A popular way to make a color space like RGB into an absolute color is to define an ICC profile, which contains the attributes of the RGB. This is not the only way to express an absolute color, but it is the standard in many industries. RGB colors defined by widely accepted profiles include sRGB and Adobe RGB.
This is achieved by encoding RGB image data into a composite black and white image, with separated color difference data . For example with Y ′ C b C r {\displaystyle Y'C_{b}C_{r}} , gamma encoded R ′ G ′ B ′ {\displaystyle R'G'B'} components are weighted and then summed together to create the luma Y ′ {\displaystyle Y'} component.
The three values of the YCoCg color model are calculated as follows from the three color values of the RGB color model: [2] [] = [] [] The values of Y are in the range from 0 to 1, while Co and Cg are in the range of −0.5 to 0.5, as is typical with "YCC" color models such as YCbCr.
The practical result of these different gamma values per color channel is that what looks clean and neutral on a YUV screen looks like it has a slight pink tint on an RGB screen if no proper YUV --> RGB conversion is applied. The complimentary case is where unconverted RGB footage is shown on a YUV monitor and turns out slightly greenish.