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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) Occurs when word flaming is lost in a serial signal so that the relative value of a bit is incorrect. This is generally reset at the next serial signal, TRS-ID for composite and EAV/SAV for component.
b) The erroneous reading of a serial bit stream when the recovered clock phase drifts enough to miss a bit. c) A phenomenon which occurs in parallel digital data buses when one or more bits gets out of time in relation to the rest. The result is erroneous data. Differing cable lengths is the most common cause.
Industry:Entertainment
Originally designed to test early colour camera encoders, it is commonly (albeit incorrectly) used as a standard test signal.
The saturated colour bars and luminance grey bar are usually used to cheque monitors for colour accuracy. The saturated colour bars are a poor test of any nonlinear circuit or system and at best, show video continuity. Testing a video system using colour bars is analogous to testing an audio system using a simple set of monotonal frequencies. Many colour TV test signals have been developed to accurately assess video processing equipment such as ADCs, compressors, etc.
Industry:Entertainment
A) A continuous series of bits transmitted on a line. b) A binary signal without regard to grouping according to character.
Industry:Entertainment
A video test signal widely used for system and monitor setup. The test signal, typically containing eight basic colors: white, yellow, cyan, green, magenta, red, blue, and black, is used to cheque chrominance functions of colour TV systems. There are two basic types of NTSC colour bar signals in common use. The terms “75% bars” and “100% bars” are generally used to distinguish between the two types. While this terminology is widely used, there is often confusion about exactly which parameters the 75% versus 100% notation refer to.
a) RGB Amplitudes: The 75%/100% nomenclature specifically refers to the maximum amplitudes reached by the Red, Green, and Blue signals when they form the six primary and secondary colours required for colour bars. For 75% bars, the maximum amplitude of the RGB signals is 75% of the peak white level. For 100% bars, the RGB signals can extend up to 100% of peak white. Refer to the following two figures.
b) Saturation: Both 75% and 100% amplitude colour bars are 100% saturated. In the RGB format, colours are saturated if at least one of the primaries is at zero. Note: In the two associated figures that the zero signal level is at setup (7.5 IRE) for NTSC.
c) The Composite Signal In the composite signal, both chrominance and luminance amplitudes vary according to the 75%/100% distinction. However, the ratio between chrominance and luminance amplitudes remains constant in order to maintain 100% saturation.
d) White Bar Levels: colour bar signals can also have different white bar levels, typically either 75% or 100%. This parameter is completely independent of the 75%/100% amplitude distinction and either white level may be associated with either type of bars.
e) Effects of Setup: Because of setup, the 75% signal level for NTSC is at 77 IRE. The maximum available signal amplitude is 100 – 7.5 or 92.5 IRE. 75% of 92.5 IRE is 69.4 IRE, which when added to the 7.5 IRE pedestal yields a level of approximately 77 IRE.
Industry:Entertainment
An information processing unit intended to extract the binary message and associated bit-rate clock included in a PCM signal.
Industry:Entertainment
A composite video signal that produces a black screen when viewed on a television receiver.
Industry:Entertainment
A) A bitmap is the digital representation of an image in terms of pixel values. Storing an image as a bitmap is the most space-consumptive method of storing an image. b) An image consisting of an array of pixels that can be displayed on a computer monitor.
Industry:Entertainment
A) The portion of a colour video signal that resides on the backporch between the breezeway and the start of active video that contains a sample of the colour subcarrier used to add colour to a signal. It is used as a colour synchronisation signal to establish a reference for the colour information following it and is used by a colour monitor to decode the colour portion of a video signal. The colour burst acts as both amplitude and phase reference for colour hue and intensity. The colour oscillator of a colour television receiver is phase locked to the colour burst. b) A nine-cycle-NTSC burst of colour subcarrier which is imposed on blanking after sync. colour burst serves as the reference for establishing the picture color.
Industry:Entertainment
The number of bits used to represent the colour information of a pixel.
Industry:Entertainment
Computation of the tristimulus values of colours in terms of one set of primaries from the tristimulus values of the same colours in another set of primaries. Note: This computation may be performed electrically in a colour television system.
Industry:Entertainment
