In the active video portion of the video waveform, the 1.0-volt (100 IRE) level. See also video waveform.

Luminance, corresponding to the brightness of an image. See also luminance and Y/R-Y/B-Y.

A color space (color component encoding format) based on YIQ or YUV. Y is luminance, but the two chroma signals (I and Q or U and V) are combined into a composite chroma called C, resulting in a two-wire signal. C is derived from I and Q as follows:

C - I cos(2\xb9 fsct) + Q sin(2\xb9 fsct)

where fsc is the subcarrier frequency. YC-358 is the NTSC version of this luminance/chrominance format; YC-443 is the PAL version. Both are referred to as S-Video formats.

A color space (color component encoding format) used in decoding, in which Y is the luminance signal and I and Q are the chrominance signals. The two chrominance signals I and Q (in-phase and quadrature, respectively) are two-phase amplitude-modulated; the I component modulates the subcarrier at an angle of 0 degrees and the Q component modulates it at 90 degrees. The color burst is at 33 degrees relative to the Q signal.

The amplitude of the color subcarrier represents the saturation values of the image; the phase of the color subcarrier represents the hue value of the image.

Y = 0.299R + 0.587G + 0.114B
I = 0.596R - 0.275G - 0.321B
Q = 0.212R - 0.523G + 0.311B

A name for the YUV color component encoding format that summarizes how the chrominance components are derived. Y is the luminance signal and R-Y and B-Y are the chrominance signals. R-Y (red minus Y) and B-Y (blue minus Y) are the color differences or chrominance components. The color difference signals R-Y and B-Y are derived as follows:

Y = 0.299R + 0.587 + 0.114B

Y/R-Y/B-Y has many variations, just as NTSC and PAL do. All component and composite color encoding formats are derived from RGB without scan standards being changed. The matrix (amount of red, green, and blue) values and scale (amplitude) factors can differ from one component format to another (YUV, Y/R-Y, B-Y, SMPTE Y/R-Y, B-Y).

A color space (color component encoding format) used by the PAL video standard, in which Y is the luminance signal and U and V are the chrominance signals. The two chrominance signals U and V are two-phase amplitude-modulated. The U component modulates the subcarrier at an angle of 0 degree, but the V component modulates it at 90 degrees or 180 degrees on alternate lines. The color burst is also line-alternated at +135 and -135 degrees relative to the U signal. The YUV matrix multiplier derives colors from RGB via the following formula:

Y = .299R + .587 G + .114 B
CR = R - Y
CB = B - Y

In this formula, Y represents luminance; red and blue are derived from it: CR denotes red and (V), CB denotes blue. V corresponds to CR; U corresponds to CB c. The U and V signals are carried on the same bandwidth. This system is sometimes referred to as Y/R-Y/B-Y.

The name for this color encoding method is YUV, despite the fact that the order of the signals according to the formula is YVU.