CMN-91
Appendix C
Installation and Operation Manual
Glossary
© 2016 Imagine Communications Corp. Proprietary and Confidential.
Revision D | Page 187
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.
PAT Program Association Table (see extended definition on the following page)
Pane On TVM/VTM Series units, one quadrant in a multi-quadrant screen (see also Quad or Multi)
Passive Looping Video and audio signals routed through components, even if power is removed. Signals
are not amplified or processed, maintaining transparency.
Payload Identifier see Video Payload ID.
PCR Program Clock Reference (see extended definition on the following page)
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.
PES Packetized Elementary Stream (see extended definition on the following page)
PID Packet Identifier (see extended definition on the following page)
PIP Picture-in-Picture. A scaled view of the full motion video and audio level meters for a given Program.
The scaled view is usually arranged in a mosaic so that multiple Programs can be viewed at once. The
option exists to view PIP full screen on command to avoid any scaling and minimize or eliminate format
conversion.
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.
PMT Program Map Table (see extended definition on the following page)
Pollution Degree A measurement of the foreign materials such as conductive dust, gas, and moisture
between the internal areas of the product and the outside environment. Pollution Degrees are 1,2 3,
and 4.
Pollution Degree 1 describes conditions where no pollution occurs or only dry, nonconductive
pollution occurs. This is normal for equipment located in clean rooms. The pollution classified under
Pollution Degree 1 has no environmental influence.
Pollution Degree 2 describes conditions where dry, nonconductive pollution occurs. This is normal in
an office environment. Temporary conductivity caused by condensation may occur when the unit is
not in service.
