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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.
CinePak is a compression scheme dedicated to PC environments, based on a vector quantization algorithm. CinePak is a highly asymmetrical algorithm, i.e., the encoding takes much more processing power than the decoding process. The CinePak algorithm is developed by Radius, and is licensed by a range of companies. Both Microsoft™ Windows 95 and Apple’s QuickTime have built in CinePak, for instance.
Industry:Entertainment
a) A video file.
b) In keying, the trigger point or range of a key source signal at which the key or insert takes place.
c) The control that sets this action. to produce a key signal from a video signal, a clip control on the keyer control panel is used to set a threshold level to which the video signal is compared.
d) In digital picture manipulators, a manual selection that blanks portions of a manipulated image that leave one side of the screen and “wraps” around to enter the other side of the screen.
e) In desktop editing, a pointer to a piece of digitized video or audio that serves as source material for editing.
Industry:Entertainment
a) An electronic limit usually imposed in cameras to avoid overly bright or dark signals. When improperly applied, can result in loss of picture information in very bright or very dark areas. Also used in switchers to set the cutoff point for mixing video signals. b) The electronic process of shearing off the peaks of either the white or black excursions of a video signal for limiting purposes. Sometimes, clipping is performed prior to modulation, and sometimes to limit the signal so it will not exceed a predetermined level.
Industry:Entertainment
Code/Decode. An encoder plus a decoder is an electric device that compresses and decompresses digital signals. CODECs usually perform A-to-D and D-to-A conversion.
Industry:Entertainment
Adjustment of color in the camera to meet a desired standard, i.e., color bar, sponsor’s product, flesh tones. Also may be referred to as “white balance.”
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 check chrominance functions of color TV systems. There are two basic types of NTSC color 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 colors required for color 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 color bars are 100% saturated. In the RGB format, colors 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: Color 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
a) The portion of a color video signal that resides on the backporch between the breezeway and the start of active video that contains a sample of the color subcarrier used to add color to a signal. It is used as a color synchronization signal to establish a reference for the color information following it and is used by a color monitor to decode the color portion of a video signal. The color burst acts as both amplitude and phase reference for color hue and intensity. The color oscillator of a color television receiver is phase locked to the color burst. b) A nine-cycle-NTSC burst of color subcarrier which is imposed on blanking after sync. Color burst serves as the reference for establishing the picture color.
Industry:Entertainment
A device used to achieve compatibility between two items of audio/video equipment.
Industry:Entertainment
Ancillary program data, especially program clock reference (PCR), which are uncoded and are transmitted at least every 100 ms after the TS header of a data stream (packet information, PID) belonging to a program.
Industry:Entertainment
