[A]
AC Adapter:
Alternating Current Adapter; when plugged to AC Power (usually
117VAC/60Hz in the United States) it produces 12VDC, 24VAC or
others. "UL Listed" and "Regulated" recommended. It is also called
Power Transformer.
AC Power:
Alternating Current Power. In the United States, the standard AC
Power is single-phase 117VAC/60Hz and is provided from power outlets
in the house. 24V AC power can be produced from an AC Adapter.
AGC (Automatic Gain Control):
Automatically adjusts the video quality in low light condition.
Alarm Sensor:
Like Video Motion Detector, detects changes of motion to produce
an alarm.
ALC (Automatic Light Control):
Allows the auto-iris circuitry to either take bright spots more
into consideration (peak), bringing out detail in bright areas, or
less into consideration (average) bringing out detail in shadows.
Select this mode when an auto-iris lens is used.
Algorithm:
A procedure or formula for solving a problem.
Ampere (amp):
The unit of measure for the rate
of electrical current flow characterized by the symbols l (in
Ohm's law formulas) and A. One ampere is the current flowing through
one ohm of resistance at one volt potential.
Analogue (Analog):
Continuously variable numerical values
such as voltage, current, etc.(The CCD camera produces analogue
video signals.)
Angle of View:
The scene angle that a video camera lens can show on the
monitor, like Diagonal Angle, Horizontal Angle and Vertical Angle,
usually described in degree. More details...
ANSI:
American National Standards Institute. This organization is
responsible for approving U.S. standards in many areas, including
computers and communications.
Aperture:
The (Camera) lens opening that
controls the amount of light that reaches the image sensor. Aperture
is expressed as F-stop, e.g. F2.8 or f/2.8. The smaller the
F-stop number (or f/value), the larger the lens opening (aperture).
ARP:
Address Resolution Protocol; for mapping an IP address to a physical
machine address.
ASCII:
American (National) Standard Code for Information Interchange. A
standard character-to-number encoding widely used in the computer
industry.
ASIS:
American Society for Industrial Security.
Aspect Ratio:
The ratio of the vertical to the horizontal image size; 3:4 is the
NTSC standard.
Aspherical Lens:
A lens designed with a non spherical shape so that it passes more
lights or decreases barrel distortion on wide angle lenses.
Attenuation:
A decrease or loss in a signal, usually measured in decibels.
Auto-focus Lens:
Automatically adjusts the lens focus from surrounding scene and
keeps a moving object in focus.
Auto Iris (Automatic Iris):
A device in the camera lens that
self-adjusts to light level changes. The Iris opens and closes to
control the amount of light passing through the lens to reach the
image sensor.
Automatic Gain Control
(AGC):
A feature of cameras that
enhances videos of low lights to maintain the output video signal
strength.
Automatic Level Control (ALC):
Allows the auto-iris circuitry to either take bright spots more into
consideration (peak), bringing out detail in bright areas, or less
into consideration (average) bringing out detail in shadows.
Auto Terminating:
Automatically select the correct termination depending on whether
the video output is connected.
AWB
(Automatic White Balance):
A feature of cameras that
automatically adjusts to varying light conditions to maintain the
correct white balance on the image. Proper camera white balance has
to take into account the "color temperature" of a light source,
which refers to the relative warmth or coolness of white light. For
more detail, click here.
AWG
(American Wire Gauge):
AWG is the U.S. standard measuring
gauge for certain conductors, including copper. The higher the AWG
number the thinner the wire. This measure stems from the fact that
the original measurement represented the number of times the wire
was run through a wire machine which thus reduced the diameter of
the wire.
 More
Detail.
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[B]
Bandwidth:
The capacity of the transmission medium stated in bits per
second or as a frequency. Or, the amount of data that can be
transmitted in a fixed amount of time. For digital devices, the
bandwidth is usually expressed in bits per second(bps) or bytes per
second. For analog devices, the bandwidth is expressed in cycles per
second, or Hertz (Hz).
Back Light Compensation (BLC):
Electronically compensates for high background lighting to give
detail which would normally be silhouetted.
Baud:
The rate at which data is
transferred. Named after Maurice Emile Baud. The Baud rate is
equivalent to bits per second in cases where each data event
represents exactly 1 bit. To communicate the baud rates of the
equipment must be set the same. Note the baud rate and bit rate in a
system can be different.
More
Detail.
Bifocal Lens:
A lens system that has two different focal length lenses and
images two identical or different scenes onto a single camera
sensor. The two captured scenes appear as a split image on the
monitor.
Binary:
A numbering system with only two values: 0 (zero) and 1 (one).
Bit Rate:
The term bit rate is a
synonym for data transfer rate. Bps = Bytes per second, bps = bits
per second. The digital equivalent of bandwidth, bit rate is
measured in bits per second. It is used to express the rate at
which the compressed bit stream is transmitted. The higher the bit
rate, the more information that can be carried.
More
Detail.
Blanking:
The process whereby the beam in a CRT is cut off during the retrace
period.
BLC (Back
Light Compensation):
Cameras with BLC feature will
adjust the brightness level of the image to compensate for the
bright background so that more detail of the dark objects can be
seen. For an example, when a camera is directed toward a door, the
bright light from outside will normally make the overall image too
bright to show detail on a subject backing to the door. BLC will
compensate for the bright background so foreground objects are not
silhouetted.
BNC
Connector:
BNC connector is a type of RF
connector used for terminating coaxial cable. It is used for
professional video connections. It is an alternative to the RCA
connector. See also RCA Connector
More
Detail.
bps:
Bits Per Second is the unit used for measuring line speed, the
number of information units transmitted per second.
Brightness Control:
The manual bias control on a cathode ray tube or other display
device that controls the average brightness and the contrast of a
picture.
Browser:
An application program that provides a way to look at and interact
with all the information on the World Wide Web. Netscape and
Microsoft Internet Explorer are the two browsers that vast majority
uses.
Byte:
Abbreviated with capital "B". A unit of data that is eight bits long
and is used by most computers to represent a character such as a
letter, number or symbol.
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[C]
C-Mount:
An industry standard for lens mounting. C-Mount is 1-inch
diameter with 32 threads per inch. A C-Mount lens needs C-ring when
it is mounted at a CS-Mount camera.
C-MOS:
Complementary - Metal Oxide Semiconductor. A video image sensor
chip that produces much lower quality picture than CCD chip.
Camera Format:
Video camera's CCD chips format; 2/3", 1/3", 1/4", etc.
Camera Sensor:
Video image sensor. CCD or C-MOS chip.
CATV:
Cable Access Television
C/CS Mount:
Cine mount. The first standard
for CCTV lens screw mounting. It is defined with the thread of
1''(25.4 mm) in diameter and 32 threads/inch, and the back
flange-to-CCD distance of 17.526 mm (0.69''). The C-mount
description applies to both lenses and cameras.
CS Mount (Cine Short Mount) is the
newer standard for camera lens mounting. It uses the same physical
thread as the C-mount, but the back flange-to-CCD distance is
reduced to 12.5 mm.
C-mount lenses can be put on both,
C-mount and CS-mount cameras, but must use a C-moun adaptor when
used on a CS-mount camera.
CCD
(Charge-Coupled Device):
CCD and CMOS are two main types of
technology in current security cameras. CCDs containing grids of
pixels are used in Digital camera, Image scanner and video cameras
as light-sensing devices.
CCDs boast higher sensitivity, and higher dynamic range than CMOS
sensors while CMOS offers lower
product cost and lower power consumption.
More
Detail.
CCIR:
Committée Consultatif
International des Radiocommuniqué, which is the European
standardization body that has set the standards for television in
Europe. It was initially monochrome; therefore, today the term CCIR
is usually used to refer to monochrome cameras that are used in PAL
countries.
More
Detail
CCTMA:
Closed Circuit Television Manufacturers Association.
CCTV
(Closed Circuit Television):
A system in which the circuit is
closed and all the elements are directly connected. The most widely
applications of CCTV are in the security industry.
More
Detail
CCTV Camera:
A part of the CCTV system that captures the video pictures.
CCTV Monitor:
A part of the CCTV system that receives the video pictures from a
CCTV camera and displays them.
CIF (Common
Intermediate Format):
CIF is part of the ITU
H.261videoconferencing standard. It specifies a data rate of 30
frames per second (fps), with each frame containing 288 lines and
352 pixels per line. A related standard, QCIF (Quarter CIF),
transfers one fourth the amount of data.
More
Detail
CMOS:
Complementary-symmetry/Metal-Oxide
Semiconductor. CMOS image sensors which use the ASP (Active Pixel
Sensor) technology, are one of the two major types of image sensors
used in security cameras. The other is CCD image sensors
Comparing to CCDs, CMOS sensors
are cheaper to make and consume less power, but they are more prone
to noise.
More
Detail
Coaxial
Cable:
Coaxial cable is the most common type
of cable used for transmitting a video signal through copper wire.
This type of wiring has a coaxial cross-section where an outer
shielding protects the actual interior signal conductor from
electromagnetic interference. In the CCTV industry, the term "coax"
usually refers to RG-59 cable with BNC-type plug ends.
More
Detail
CODEC
(COder/DECoder):
A CODEC is a device or software
that compresses and/or decompresses digital signals. It is used for
converting audio/video signals from analog to digital and vise vesa
during the process of data transmission and storage. Each data
format such MP4, AVI, etc. needs its own CODEC.
More Detail
Color Saturation:
The degree of mixture of a color and white. High saturation means
little or no white.
Component Video:
A type of video information that is transmitted or stored as two or
more separate signals. Opposed to composite video.
Composite Video:
A combined signal in a television transmission. Standard format such
as NTSC, PAL or SECAM. The picture signal, blanking signal, and
vertical/horizontal synchronizing signals are all combined.
CRT:
Cathode Ray Tube. The vacuum tube part of a monitor or television.
CS-Mount:
An industry standard for lens mounting. CS-Mount is 1 inch diameter
with 32 threads per inch. A C-Mount lens needs C-ring when it is
mounted at a CS-Mount camera.
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[D]
Date/Time Generator:
Installed between a CCTV camera and a monitor, it generates the
information of Date, Time and camera ID.
DC Power:
Direct Current Power; can be derived from an AC adapter or from
a battery. Among DC voltages of 6, 9, 12, 24, 28, 12VDC is most
common in the CCTV industry.
Decibel (dB):
The power or voltage ratio of two signals.
DIP switches:
Dual Interface Poll switches usually allow you to change the
configuration of a circuit board to suit your application.
DMZ:
Detection of Motion Zone
DHCP:
Dynamic Host Configuration Protocol; lets network administrators
manage centrally and automate the assignment of IP addresses in an
organization's network.
DIN:
Multi-wire cable with DIN connectors at both ends. Usually has 5
or 6 inner wires. Different diameter and configuration from maker to
maker. Pictures of DIN connectors or, more details about DIN
Cable...
Distortion:
A general term when the object is not shown exactly as is.
DNS:
1)Domain Name System. A general purpose distributed, replicated,
data query service. Its principal use is the lookup of host IP
addresses based on host names. 2)Domain Name Server. A computer that
converts host names, such as www.pelikancam.com to its corresponding
IP Address, such as 67.100.253.111
DRAM:
Dynamic Random Access Memory. Most common RAM (Random Access
Memory) for PC.
DSL:
Digital Subscriber Line. A technology for bringing
higher-bandwidth information to homes and businesses over ordinary
copper telephone lines.
DVR
(Digital Video Recorder):
A device that records video/audio
signals onto hard drive-based digital storage medium. In the CCTV
security field, there are generally two types of DVRs, PC-based DVRs
and Embedded DVRs. DVRs are replacing the traditionally widely used
VCRs.
Dwell Time:
The length of time a switcher displays one camera before sequencing
to the next.
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[E]
EIA:
Electronic Industries Association. American standard for B/W
camera system.
ELC (Electronic Light Control):
Compensates for moderate light changes in indoor applications
without the use of auto iris lenses. Select this mode when a fixed
iris lens or manual iris lens is used.
Electronic Shutter:
Compensates for moderate light changes in indoor applications
without the use of auto iris lenses.
EMI:
Electro-Magnetic Interference.
Ethernet:
The most widely installed Local Area Network (LAN) technology.
Specified in a standard IEEE802.3.10/100 BASE-T, the most commonly
installed Ethernet system, provides transmission speed up to 100
megabits per second.
Extranet:
A private network. It uses the Internet Protocol to securely
share part of a business information with suppliers, vendors or
others.
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[F]
FCC:
Federal Communications Commission; controls also wireless camera
system as one of the commercial broadcasting systems.
FFL:
Fixed Focal Length Lens
Fiber-Optic Cable:
One of the video transmission ways, being used for a long distance
transmission up to miles.
Field:
One video frame is composed of two
fields; one field consists of the odd numbered lines in the frame
and the other field consists of the even numbered lines.
Field Frequency:
The number of fields per second.
Field Of View:
FOV. The width, height or diameter of a scene to be monitored.
Usually determined by the focal length of a lens, the sensor format
and the distance to the objects.
Firewall:
A set of programs that protects the resources of a private network
from outside users.
FL:
Focal Length. The distance from the center of a lens (or, the
secondary principal point, if it has) to the focal point (sensor).
The longer the focal length, the narrower is the angle of view.
Flange-back Adjusting Ring:
Some models of CCTV cameras have built-in Flange-back Adjusting
Ring, which adjusts the back-focal distance or picture focus. A
C-Ring (5mm spacer ring) is not required when a C-Mount lens is to
be mounted to a camera that has built-in Flange-back Adjusting Ring.
Flash Memory:
Or flash RAM (Random Access Memory). A type of constantly powered
nonvolatile memory that can be erased and reprogrammed in units of
memory called blocks.
f-number (f-stop):
Optical or lens speed. Smaller f-number means faster lens. .
Focal Length:
FL. The distance from the center of a lens (or, the secondary
principal point, if it has) to the focal point (sensor). The longer
the focal length, the narrower is the angle of view.
FOV:
Field of View. The width, height or diameter of a scene to be
monitored. Usually determined by the focal length of a lens, the
sensor format and the distance to the objects.
Frame:
A whole video image; is composed of two interlaced fields. A CCD
chip produces 30 frames per second at NTSC system and 25 frames at
PAL.
Frame Frequency:
The number of frames per second. The frame frequency is half the
field frequency.
FTP:
File Transfer Protocol. A way to exchange files between computers on
the Internet
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[G]
Gamma:
Degree of contrast in a video picture between output magnitude
and input magnitude.
Gamma
Correction:
A correction of the linear response
of a camera in order to compensate for the monitor phosphor screen
non-linear response. It is measured with the exponential value of
the curve describing the non-linearity. A typical monochrome
monitor's gamma is 2.2, and a camera needs to be set to the inverse
value of 2.2(which is 0.45) for the overall system to respond
linearly (i.e., unity). All ICR's cameras have a gamma correction of
0.45.
GB:
Gigabyte.
Genlock:
A device that adjusts the frequency of internal sync to an external
data.
Ghost:
A shadowy or weak image in the received picture, offset to either
the right or to the left of the primary image.
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[H]
HTML:
Hyper Text Markup Language. A set of codes inserted in a file
intended for display on a World Wide Web browser page.
HUB:
As a network product, a hub may include a group of modem cards
for dial-in users, a gateway card for connections to a Local Area
Network (LAN), and a connection to a line.
HUE
(color):
One of the three characteristics of
video picture, the other two are saturation and luminance. Hue
defines color on the basis of its position in the spectrum.
More Detail
Hz (Hertz):
Cycles per second.
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[ I ]
ICMP:
Internet Control Message Protocol. A message control and
error-reporting protocol.
Impedance:
Electrical characteristic of a system or component, expressed in
ohms. CCTV industry has standardized 75-ohm impedance.
Infrared (IR) Light:
Invisible light beyond the 750 nanometers (red end of the
visible lights).
INT:
Internal sync mode that sets to internal 2:1 interlace.
Internet:
The Internet is the worldwide, publicly accessible network
of interconnected computer networks that transmit data by packet
switching using the standard Internet Protocol (IP). It is a
"network of networks" that consists of millions of smaller domestic,
academic, business, and government networks, which together carry
various information and services, such as electronic mail, online
chat, file transfer, and the interlinked Web pages and other
documents of the World Wide Web.
Contrary to some common usage, the Internet and the World Wide
Web are not synonymous: the Internet is a collection of
interconnected computer networks, linked by copper wires,
fiber-optic cables, wireless connections, etc.; the Web is a
collection of interconnected documents, linked by hyperlinks
and URLs. The World Wide Web is accessible via the Internet, along
with many other services including e-mail, file sharing and others. See also LAN, WAN
Intranet:
A private network. It may consist of many LAN and/or WAN.
IP:
Internet Protocol. A set of rules to send and receive messages at
the Internet address level. More details...
Iris:
An adjustable opto-mechanical aperture built into a camera that
controls the amount of lights coming through the lens.
ISDN:
Integrated Service Digital Network. A set of standard for digital
transmission over ordinary telephone copper wire.
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[J]
JPEG:
Joint Photographic Experts Group. A graphic image file or a image
compression algorithm.
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[K]
KB:
Kilobyte
Kbps:
Kilobits per second. A measure of bandwidth.
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[L]
LAN (Local
Area Network):
A Local Area Network (LAN) is a
computer network covering a small local area, like a home,
office, or small group of buildings such as a home, office, or
college.
The mostly widely used term
"Internet" refers to the global network that consists of all small
computer networks, of which LAN is one type of them. LANs are
connected together by WANs (Wide Area Networks).
The defining characteristics of LANs
in contrast to
WANs (wide area networks) are: their much higher data rates;
smaller geographic range; and that they do not require leased
telecommunication lines. See also Internet, WAN.
LED:
Light Emitting Diode.
Lens Mount:
The area where a lens is mounted. There are two types; C- or
CS-Mount.
Lens Speed:
Optical speed, expressed by f-number. Smaller f-number means faster
lens.
Linux:
An UNIX-like operating system. Very efficient and fast-performing
system.
LL:
Line Lock mode
LNB (Low Noise Block Converter):
The part of satellite dish that hangs off of the arm and looks like
a flashlight. It is what captures the digital signal from the
satellite.
Luminance:
Luminance defines the luminous
intensity of a video signal: brightness and contrast. A color video
picture contains two components, luminance - Y (brightness and
contrast) and Chrominance - C (hue and saturation). It is normally
measured by LUX.
LUX:
Measurement unit of the
intensity of light. It is defined as the illumination of a surface
when luminous flux of 1 lumen falls on an area of 1 m 2;
It is also known as lumens per square metre. One lux is equal to
approximately 0.09290 foot candle. Minimum illumination is an
important specification of a CCTV camera. It reveals the minimum
lighting needed for the camera to produce visible image.
More Detail
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[M]
Multiplexer
(Mux):
Multiplexer is a video
switching device that accepts video input from multiple cameras and
converts them to all display on one monitor and / or video recorder,
similar to a
quad
video processor. However, a multiplexer is far
more advanced than a simple quad processor. Video multiplexers use
time division multiplexing, meaning that a full
frame
of video from each camera is recorded every few seconds. While
multiplexed video does not achieve true
realtime display or recording (there is a slight drag to the
images on playback), multiplexers do offer the capability to change
between a view of several cameras and a solid closeup view of only a
single camera's view on playback of recorded video. When using
multiple cameras, quads and multiplexers help to cut down on the
amount of additional equipment needed for a dedicated surveillance
system. However, DVR
digital video recorders with multiple video inputs are quickly
replacing quads and multiplexers. DVRs are now capable of doing what
required a processor and VCR
in the past (plus a whole lot more).
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[N]
NTSC
(National Television System Committee):
NTSC is the analog television system
in use in Canada, Japan, South Korea, the United States, and some
other places, mostly in the America. It is named for the National
Television System Committee, the industry-wide standardization body
that created it.
More
Detail
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[P]
PAL (Phase
Alternation Aine):
PAL is another major analog
television system in use in large part of the world, mainly Europe,
China, and other places. PAL system denotes 625 Lines and 50Hz
comparing to NTSC system's 525 Lines and 60Hz.
More
Detail
PTZ
(Pan/Tilt/Zoom):
PTZ stands for equipment (mostly
cameras) with the ability to pan,
tilt,
and
zoom, usually by remote user control. Much of PTZ equipment is
completely integrated, meaning there is only one controller
necessary to operate all three features.
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[Q]
Quad
Processor:
Quad Processor is a video switching
device that accepts video input from four cameras and converts them
to all display on one monitor and / or video recorder.
When using multiple cameras, quads and multiplexers help to
cut down on the amount of additional equipment needed for a
dedicated surveillance system. However, DVR digital video recorders
with multiple video inputs are quickly replacing quads and
multiplexers. DVRs are now capable of doing what required a
processor and VCR in the past (plus a whole lot more).
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[R]
RCA
Connector:
RCA connector is a common
connector plug for standard consumer video and audio equipment. This
type of connector plug may also be described as a "phono" plug. RCA
jacks are found on all VCRs
and televisions equipped to handle a composite video input. In most
cases, RCA jacks are color coded yellow, white, and red. BNC plugs
are easily adapted to standard consumer RCA connectors using a
simple one-piece plug adapter.
More
Detail
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[S]
Saturation
(Color) :
A color's saturation is
the intensity of the color in the active picture. It is based on
the color's
purity;
a highly saturated hue has a vivid, intense color, while a less
saturated hue appears more muted and grey.
More Detail
Simplex,
Duplex, Triplex, Pentaplex:
These terms concern the operation of
video recorders (VCR, DVR) and multiple camera video processors like
quads and multiplexers. They indicate the number of device's
capacities that can be used simultaneously. For instance, a simplex
device is only capable of performing one type of task at a time,
whether that be recording or playback. A duplex device can perform
two simultaneous functions like record and configure the monitor
display. Triplex devices are capable of three tasks at the same time
(usually record, playback, and zoom or other display
functions). Pentaplex devices can perform six different tasks at the
same time. ICRealtime's DVRs are all Pentaplex devices which can
record, playback, liveview, remote liveview, remote search, and
remote configuration change simultaneously.
S/N Ratio
(Signal to Noise Ratio):
Signal to Noise Ratio
indicates the ratio of noise to actual total signal (in a video or
audio signal). The S/N number measures how much higher the signal
level is to the level of background electronic noise, so a higher
number means a clearer and crisper picture. Signal-to-noise ratio is
expressed in decibels (dB).
More
Detail
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[U]
Uninterruptible Power Supply (UPS):
UPS sometimes called an
uninterruptible power source, is a device which maintains a
continuous supply of
electric power to connected equipment by supplying power from a
separate source when utility power is not available.
More
Detail
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[W]
WAN (Wide
Area Network):
A wide area network or
WAN is a computer network covering a wide geographical area,
involving a vast array of computers. This is different from local
area networks (LANs) that are usually limited to a room, building or
campus. The most well-known example of a WAN is the Internet.
WANs are used to
connect local area networks (LANs) together, so that users and
computers in one location can communicate with users and computers
in other locations.
See also Internet, LAN.
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We are continuously working on
providing accurate and educated information for our dealers/customers.
If you find any corrections or omissions, or simply want more
information on certain subjects, please send your comments
Click here.
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