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Tektronix provides test and measurement instruments, solutions and services for the computer, semiconductor, military/aerospace, consumer electronics and education industries worldwide.
If three components are to be conveyed in three separate channels with identical unity excursions, then the Pb and Pr color difference components are used. These scale factors limit the excursion of EACH color difference component to –0.5 … +0.5 with respect to unity Y excursion: 0.886 is just unity less the luma coefficient of blue. In the analog domain, Y is usually 0 mV (black) to 700 mV (white), and Pb and Pr are usually ±350 mV. YPbPr is part of the CCIR Rec. 709 HDTV standard, although different luma coefficients are used, and it is denoted E'Pb and E'Pr with subscript arrangement too complicated to be written here. YPbPr is employed by component analog video equipment such as M-II and Betacam; Pb and Pr bandwidth is half that of luma. A version of the (Y, R-Y, B-Y) signals specified for the SMPTE analog component standard.
Industry:Software
The general set of CAV signals used in the PAL system as well as for some encoder and most decoder applications in the NTSC systems.
Y is the luminance, R-Y is the 1st color-difference signal and B-Y is the 2nd color-difference signal.
Industry:Software
Luminance and color difference components for PAL systems. Y, U, and V are simply new names for Y, R-Y, and B-Y. The derivation from RGB is identical. In composite NTSC, PAL or S-Video, it is necessary to scale (B-Y) and (R-Y) so that the composite NTSC or PAL signal (luma plus modulated chroma) is contained within the range –1/3 to +4/3. These limits reflect the capability of composite signal recording or transmission channel. The scale factors are obtained by two simultaneous equations involving both B-Y and R-Y, because the limits of the composite excursion are reached at combinations of B-Y and R-Y that are intermediate to primary colors. The scale factors are as follows: U = 0.493 * (B-Y); V = 0.877 * (R-Y). U and V components are typically modulated into a chroma component: C = U * cos(t) + V * sin(t) where t represents the ~3.58 MHz NTSC color sub-carrier. PAL coding is similar, except that the V component switches Phase on Alternate Lines (±1), and the sub-carrier is at a different frequency, about 4.43 MHz. It is conventional for an NTSC luma signal in a composite environment (NTSC or S-Video) to have 7.5% setup: Y_setup = (3/40) + (37/40) * Y. A PAL signal has zero setup. The two signals Y (or Y_setup) and C can be conveyed separately across an S-Video interface, or Y and C can be combined (encoded) into composite NTSC or PAL: NTSC = Y_setup + C; PAL = Y + C. U and V are only appropriate for composite transmission as 1-wire NTSC or PAL, or 2-wire S-Video. The UV scaling (or the IQ set, described below) is incorrect when the signal is conveyed as three separate components. Certain component video equipment has connectors labeled YUV that in fact convey YPbPr signals.
Industry:Software
A term used to describe the separation of video signal components used in systems such as Hi-8 and S-VHS. Generically called S-Video, all Videonics video products support the (Y/C) format.
Industry:Software
Connections between videotape recorders and between videotape recorders and cameras, monitors, and other devices that keep luminance and chrominance separate and thus avoid cross-color and cross-luminance. See also S-Video.
Industry:Software
Decoder used to separate luma and chroma in an (M) NTSC or (B, D, G, H, I) PAL system.
Industry:Software
The vertical axis of a graph. When a television signal is examined in one dimension, the y-axis is usually signal strength. When it is examined in three dimensions, the y-axis is usually vertical resolution.
Industry:Software
Kodak’s Photo YCC color space (for PhotoCD) is similar to YCbCr, except that Y is coded with lots of headroom and no footroom, and the scaling of Cb and Cr is different from that of Rec. 601-1 in order to accommodate a wider color gamut. The C1 and C2 components are subsequently subsampled by factors of two horizontally and vertically, but that subsampling should be considered a feature of the compression process and not of the color space.
: Y_8b = (255/1.402 * Y
: C1_8b = 156 + 111.40 * (Bgamma - Y)
: C2_8b = 137 + 135.64 * (Rgamma - Y)
Industry:Software
a) A video system employing luminance and two chroma components directly related to the red and blue components. This professional component video system is used in studios and requires special equipment.
Interface devices are used to link the various component systems, i.e., RGB, Y/C, YUV, and YIQ (A system similar to YUV).
b) A color model used chiefly for video signals in which colors are specified according to their luminance, the Y component, and their hue and saturation, the U and V components. See Hue, Luminance, Saturation. Compare RGB.
Industry:Software
