Sony PCS-G70 User Manual

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Glossary
PCS-G70/G70P
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I-MUX
An abbreviation for Inverse Multiplexer. 
This protocol allows you to transmit the data 
at 384 Kbps via 6B-channel.
Interlaced SIF
With TV pictures, 60 fields of pictures per 
second are interlaced to provide high 
resolution and smooth motion pictures. 
The conventional videoconferencing system 
uses CIF format pictures (352 pixel × 388 
line) transmitted in 30 fields per second. In 
CIF format, smooth motion pictures like TV 
pictures cannot be obtained. In the Interlaced 
SIF format, interlaced SIF size pictures (352 
pixel × 240 line) can be transmitted at 60 
frames per second. This enables display of 
pictures with higher vertical resolution of 
352 pixel × 480 lines, providing smooth 
motion picture. However, a relatively higher 
bit rate is required as the amount of 
information is twice as much as that of the 
CIF format. 
ISDN
An abbreviation for Integrated Services 
Digital Network. This is a communication 
protocol by CCITT on transmission of 
integrated voice, video, and data. 
Bandwidths include basic (64 Kbps) and 
primary rate (1.544 and 2.048 Mbps).
ITU-T
An abbreviation for International 
Telecommunication Union, 
Telecommunications.
Lip synchronization
A function that synchronizes sound with 
motion. Sound processing is much faster 
than motion processing, thus sound and 
motion sometimes get out of step with each 
other.
MCU
An abbreviation for Multipoint Control 
Unit. When connecting a MCU, a multipoint 
videoconference can be held.
MLP
Data communication is also available during 
communication of video/audio signals 
between the videoconferencing systems. 
The MLP or HMLP is a protocol for data 
communication such as NetMeeting. Using 
the HMLP protocol allows faster data 
transmission.
MPEG4
A video coding algorithm recommended by 
the ISO/IEC based on the H.263+ standard. 
Adding some tools provides some 
improvement of picture quality compared 
with the H.263+ standard. The MPEG4 
format is commonly used for personal 
computers, cellular phones, etc.
P in P
An abbreviation for “Picture in Picture.” 
This is a function which allows you to 
monitor your own party on a small window 
on your TV monitor.
QCIF
An abbreviation for Quater CIF. The number 
of pixels is a quarter than one of CIF format.
176 pixels × 144 lines
Secondary terminal
Normally, a multipoint videoconference is 
not available unless the video and audio 
modes and transmission rate of the 
videoconferencing systems of all the sites 
are the same.
*1
 For a multipoint 
videoconference the terminal that can be 
connected in the same modes is called a 
primary terminal, while a secondary 
terminal is the terminal in which some of the 
functions are restricted since the connection 
is not enabled with the same modes. The 
restriction on the functions depends on the 
conditions described in “Notes on 
Secondary Terminals” under “in chapter 8 
Multipoint Videoconference”.
For example, this system does not transmit 
video signals to a terminal that has no 
common formats but can communicate via 
audio signals. In this case, the terminal in 
which picture viewing is not available is 
regarded as a secondary terminal.
*2
 A 
terminal communicated via a normal phone 
included in the multipoint videoconference