Imagine Videotek LLM-1770, Инструкция по установке и эксплуатации

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Appendix C
Glossary
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EDH. Error Detection and Handling. A recommended practice defined in SMPTE RP 165. A
system to generate and then detect video data errors in serial digital video systems.
Effects Keyer. A keyer which is electronically located in the mix/wipe generator portion of
a switcher. The resulting key would appear under the down stream key.
EIA Rack Space or Unit. A specific size as designated by the Electronics Industry
Association. The rack unit is 19 inches wide, and is 1.75 inches tall. A device which requires
3 EIA rack units is 19 inches wide and 5.25 inches (3x1.75 = 5.25) tall.
Elementary Stream (ES). A generic term for one of the coded video, audio or other
variable length bit streams which are packetized to form MPEG-2 transport streams.
Consists of compressed data from a single source (audio, video, data, etc.). One elementary
stream is carried in a sequence of PES packets with one and only one stream ID.
Embedded Audio. Digital audio information multiplexed onto a serial digital data stream.
Up to sixteen channels can be multiplexed on a single stream of 601 video, minimizing
cabling and routing requirement.
ENG. Electronic News Gathering
Encoded Clip Softness. In the encoded legalization process, “softness,” as applied to
encoded clips, refers to the processing of the video at the point of the clip. The clips are
applied in YCbCr color space. The clip point is either an immediate limit (no softness) or will
have a range of values leading to the clip point, all reduced to smooth the clip point to a
less immediate limit (softness).
Encoded Legalization. Limiting of the luminance and color difference signals such that,
once encoded into a composite video signal, the resultant encoded video does not violate
the maximum or minimum signal levels as defined by the specific encoding rules. NTSC and
PAL video plus various users of these types of video have many varied rules for maximum
and minimum encoding limits. Encoded legalization usually calculates first the encoded
luminance value and then the corresponding chroma value to make legalization
judgements.
Encoded Video. A combined single video signal that is constructed from either separate
GRB or luminance and two color difference video signals. NTSC, PAL, and SECAM are all
examples of encoded video.
Envelope Detection. An RF signal detection technique that does not respond to phase
variations in the carrier signal, enabling measurement of a transmitter’s incidental phase.
When used together with synchronous detection, envelope detection helps isolate either
video and/or RF as the causes of phase distortion.
External Key Input. This is an alternate source for key cut. This is usually a separate
external input to a switcher
Fade-thru-Black. A production technique which is a two step process. The first step will
fade the program video to black. The second step will fade from black to the video selected
on the preview bus. This is usually used in major scene transitions.
Fade-to-Black. A production technique which simply fades the program video to black and
program audio to silent. This is used to end programs and to escape from embarrassing
pictures or sounds.