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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.
In YUV systems, since U and V both contain information in the orange-blue range, both components must be given the same amount of bandwidth as I to achieve similar color fidelity. Very few television sets perform true I and Q decoding, due to the high costs of such an implementation.
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.
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.
RGB files are typically encoded in 8, 12, 16 or 24 bits per pixel. In these examples, we will assume 24 bits per pixel, which is written as RGB888. The standard byte format is simply r0, g0, b0, r1, g1, b1, .... YCbCr Packed pixel formats are often referred to as "YUV". Such files can be encoded in 12, 16 or 24 bits per pixel.
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.
Judd was the first to employ this type of transformation, and many others were to follow. Converting this RGB space to chromaticities one finds [4] [clarification needed The following formulae do not agree with u=R/(R+G+B) and v=G/(R+G+B)] Judd's UCS, with the Planckian locus and the isotherms from 1,000K to 10,000K, perpendicular to the locus.