Component Video Terminology

(A mini-glossary of component video terms.)

RGB: Red, Green, and Blue; the primary colors of television. Typically distributed with amplitudes of 0.7V_pp. Composite sync is often combined with the Green signal, resulting in a peak-to-peak amplitude of 1.0 volt. RGB is sometimes represented as GBR.

Y, B-Y, R-Y: The fundamental analog luminance (Y) and color difference signals (B-Y and R-Y) of component video. Each may be derived from the primary colors Red, Green, and Blue. Various other video standards (described below) are based on the Y, B-Y and R-Y components.

Y, P_b, P_r: A version of Y, B-Y, and R-Y specified for the SMPTE analog component standard. Corresponding levels for a 100% amplitude color bar signal would be 1.0V_pp luminance (0.7V_pp video with 0.3V_pp sync, zero pedestal) and 0.7V_pp for the color difference signals P_b and P_r.

Y, C_r, C_b: A digital representation of Y, B-Y, and R-Y. SMPTE 125M defines Y, Cr, and Cb levels in terms of 10-bit numbers, with luminance (Y) having 877 quantization levels with level 64₁₀ (40h) corresponding to black and level 940₁₀ (3ACh) corresponding to peak white. The color difference signals are defined as having 897 quantization levels symmetrically distributed around level 512₁₀ (200h)

YUV: Convenient shorthand commonly-but incorrectly-used to refer to the luminance and color difference signals. While Y may correctly refer to the luminance signal, U and V are actually the subcarrier modulation axes used in the PAL color encoding system.

Betacam: An analog component VTR system using ½" video cassettes developed by the Sony Corporation. It is a variation of the Y, B-Y, and R-Y component format. A 100% amplitude color bar signal in the "Betacam standard" would have a luminance level of 1V_pp (714mV_pp video with 286mV_pp sync, 54mV pedestal) and color difference levels of 817mV_pp.

MII: A "second generation" analog component VTR system developed by the Panasonic Corporation. It is a variation of the Y, B-Y, and R-Y component format. A 100% amplitude color bar signal in the "M-two format" would have a luminance level of 1V_pp (0.7V_pp video with 0.3V_pp sync, zero pedestal) and color difference levels of 648mV_pp.