Chrominance in the context of "Tints and shades"

YCbCr, Y′CbCr, also written as YC_BC_R or Y′C_BC_R, is a family of color spaces used as a part of the color image pipeline in digital video and photography systems. Like YP_BP_R, it is based on RGB primaries; the two are generally equivalent, but YC_BC_R is intended for digital video, while YP_BP_R is designed for use in analog systems.

Y′ is the luma component, and C_B and C_R are the blue-difference and red-difference chroma components. Luma Y′ (with prime) is distinguished from luminance Y, meaning that light intensity is nonlinearly encoded based on gamma corrected RGB primaries.

Y′UV, also written YUV, is the color model found in the PAL analogue color TV standard. A color is described as a Y′ component (luma) and two chroma components U and V. The prime symbol (') denotes that the luma is calculated from gamma-corrected RGB input and that it is different from true luminance. Today, the term YUV is commonly used in the computer industry to describe colorspaces that are encoded using YCbCr.

In TV formats, color information (U and V) was added separately via a subcarrier so that a black-and-white receiver would still be able to receive and display a color picture transmission in the receiver's native black-and-white format, with no need for extra transmission bandwidth.

Phase Alternating Line (PAL) is a colour encoding system for analogue television. It was one of three major analogue colour television standards, the others being NTSC and SECAM. In most countries it was broadcast at 625 lines, 50 fields (25 frames) per second, and associated with CCIR analogue broadcast television systems B, D, G, H, I and K. The articles on analogue broadcast television systems further describe frame rates, image resolution, and audio modulation.

PAL video is composite video because luminance (luma, monochrome image) and chrominance (chroma, colour applied to the monochrome image) are transmitted together as one signal. A latter evolution of the standard, PALplus, added support for widescreen broadcasts with no loss of vertical image resolution, while retaining compatibility with existing sets. Almost all of the countries using PAL are currently in the process of conversion, or have already converted transmission standards to DVB, ISDB or DTMB. The PAL designation continues to be used in some non-broadcast contexts, especially regarding console video games where it is referring to the markets other than North America and Japan.

SECAM, also written SÉCAM (French pronunciation: [sekam],Système Électronique Couleur Avec Mémoire, French for electronic colour system with memory), is an analogue colour television system that was used in France, Russia, and some other countries or territories of Europe and Africa. It was one of three major analog colour television standards, the others being PAL and NTSC. Like PAL, a SECAM picture is also made up of 625 interlaced lines and is displayed at a rate of 25 frames per second (except SECAM-M). However, due to the way SECAM processes colour information, it is not compatible with the PAL video format standard. SECAM video is composite video; the luminance (luma, monochrome image) and chrominance (chroma, color applied to the monochrome image) are transmitted together as one signal.

All the countries using SECAM have either converted to Digital Video Broadcasting (DVB), the new pan-European standard for digital television, or are currently in the process of conversion. SECAM remained a major standard into the 2000s.

In video, luma (${\displaystyle Y'}$) represents the brightness in an image (the "black-and-white" or achromatic portion of the image). Luma is typically paired with chrominance. Luma represents the achromatic image, while the chroma components represent the color information. Converting R′G′B′ sources (such as the output of a three-CCD camera) into luma and chroma allows for chroma subsampling: because human vision has finer spatial sensitivity to luminance ("black and white") differences than chromatic differences, video systems can store and transmit chromatic information at lower resolution, optimizing perceived detail at a particular bandwidth.

${\displaystyle B-Y}$ indicates a color difference signal between blue (B) and a luminance component, as part of a luminance (Y) and chrominance (C) color model. It has different meanings depending on the exact model used:

• U in YUV, a generic model used for analog and digital image formats
• Cb in YCbCr, used for digital images and video
• Pb in YPbPr, used in analog component video
• Db in YDbDr, used in analog SECAM

${\displaystyle R-Y}$ indicates a color difference signal between red (R) and a luminance component, as part of a luminance (Y) and chrominance (C) color model. It has different meanings depending on the exact model used:

• V in YUV, a generic model used for analog and digital image formats
• Cr in YCbCr, used for digital images and video
• Pr in YPbPr, used in analog component video
• Dr in YDbDr, used in analog SECAM