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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.
A) The reduction in gain applied to a picture signal at those levels corresponding to dark areas in a picture with respect to the gain at that level corresponding to the midrange light value in the picture.
b) Amplitude compression of the signals corresponding to the black regions of the picture, thus modifying the tonal gradient.
Industry:Entertainment
A) In NTSC colour television, it takes four fields to complete a colour frame. In PAL, it takes eight fields. b) Polarity of the video frame.
Color frame must alternate polarity with each frame to keep the video signal in phase.
Industry:Entertainment
A) This voltage defines the picture’s black level. Video that dips below this level such as sync pulses are called blacker than black.
b) Strictly interpreted, denotes the light level at which a video signal representing picture black is reproduced on your TV screen. In terms of light output from a TV set, black areas of the picture should be represented by an absence of light. Something that is black or below black in the video signal shouldn’t produce any light from the display. c) Some TV sets actually use Black Level as a control name. It is a far better description of the function than the most commonly found name for it, Brightness.
Industry:Entertainment
Two signals are said to be colour framed at a switcher or router when their field 1, line 10 events (field 1, line 7 in PAL) occur at the same time at the input to the switcher or router. To prevent picture distortions when changing signals at a switcher or router, the signals must be colour framed.
Industry:Entertainment
The luminance produced on the monitor display by a signal at reference black level. Since the monitor brightness control should be adjusted to align CRT beam cutoff with reference black level signal, this provides zero excitation light from the CRT (only room ambient light reflected from the CRT faceplate). Monitor black level is normally set by use of a PLUGE signal to adjust CRT beam cutoff subjectively.
Industry:Entertainment
In a system employing three colour primaries to encode image color, each primary can be located on a CIE chromaticity diagram and these points connected as a plane figure. If the apexes are then connected with an appropriate value on the white point axis, a so) id figure is produced enclosing the colour gamut for that system. (On the CIE chromaticity diagrams, the points in x, y, z space approximate an inverted tetrahedron.
In u, v, w space, they become a somewhat irregular four-cornered solid.) colours within the colour gamut solid volume can be reproduced by the system as metameric matches. colours outside the colour gamut solid volume cannot be matched. Note: The area of the cross-section from the colour gamut solid is a function of the luminance. Although it is advantageous to have the widest possible colour gamut for the ability to provide metameric matches for the largest number of colors, the required transformations from origination colorimetry to colorimetry matched to available display primaries, for example, may require large matrix coefficients and, therefore, a signal-to-noise penalty. The choice of colour gamut is a compromise between colour rendition and signal-to-noise.
Industry:Entertainment
The video signal level which is intended to produce monitor black level in the reproduced image. In systems with a setup level, i.e., the 7.5 IRE setup in a 525/59.94/2:1/NTSC composite video documented by ANSI/EIA TIA 250-C and SMPTE 170M, reference black is at the setup level. In systems with no setup level, reference black is at blanking level.
Industry:Entertainment
The maximum excursion of the picture signal black direction at the time of observation.
Industry:Entertainment
Circuitry which disables the receiver’s colour decoder if the video does not contain colour information.
Industry:Entertainment
A) Optical black is no light. An absolute black can only be produced in a scene via a light-trap, “a black hole.” b) A capped lens on the camera is the equivalent of an absolute scene black and should produce reference black level video signal from a properly adjusted studio camera.
Industry:Entertainment
