Specifications

Glossary
VTM-2000 Installation and Operation Handbook
D-7
Multi-Level Effects Applies to any effects generator which can do more than one
effect at a time. Typically, a multi level switcher can produce a Key and a Background
transition in the same effects generator at one time.
NTSC National Television Systems Committee, the color television system used in the
United States, Canada, Mexico and Japan.
NVRAM Nonvolatile RAM
Packet Identifier (PID) A unique integer value used to associate elementary streams
of a program in a single or multi-program transport stream.
Packet A packet consists of a header followed by a number of contiguous bytes from
an elementary data stream. It is a layer in the system coding syntax.
Packetized Elementary Stream (PES) The data structure used to carry elementary
stream data. The packets consist of a header followed by payload data, and a stream is
a series of packets which form an elementary stream and have a single stream
identification.
PAL Phase Alternation Line; the standard color television system in many European
and other countries.
Passive Looping Video and audio signals routed through components, even if power
is removed. Signals are not amplified or processed, maintaining transparency.
Pedestal Level An offset used in a video system to separate the active video from the
blanking level by maintaining the black level above the blanking level by a small
amount.
Pixel A Picture cell or Picture element representing one sample of picture information,
such as an individual sample of R, G, B, luminance or chrominance.
Preset Refers to establishing any condition prior to use on the Program output. This
term is used in reference to wipe patterns and is often interchanged with Preview.
Preview The video output channel used to view the intended Program results prior to
the execution of the next transition.
PRO Audio A transmitted audio channel for talent cueing via Interrupt Foldback
(IFB) to ENG vans and remote applications. Some demodulators support PRO audio
monitoring.
Program A transport stream combination of a video stream and one or more audio
and data streams associated with that video stream. In analog terms, “Program” refers
to the Base Band video and audio produced by the final output of a switcher.
Program Association Table (PAT) A list of all programs that are in the ATSC
data stream.
Program Map Table (PMT) A listing of all elementary streams that comprise a
complete (television) program.
Program Clock Reference (PCR) This is a time reference signal that is placed in
MPEG streams for the purpose of time coordinating various data streams.