Axis 27756r1 User Manual
36
AXIS Camera Station - Glossary of Terms
related technology. The primary uses for the MPEG-4 standard are Web
(streaming media) and CD distribution, conversational (videophone), and
broadcast television.
Most of the features included in MPEG-4 are left to individual developers to
decide whether to implement them or not. This means that there are probably
no complete implementations of the entire MPEG-4 set of standards. To deal
with this, the standard includes the concept of "profiles" and "levels",
allowing a specific set of capabilities to be defined in a manner appropriate
for a subset of applications.
Multicast - Bandwidth-conserving technology that reduces bandwidth usage
by simultaneously delivering a single stream of information to multiple
network recipients.
Multiplexer - A multiplexer is a high-speed switch that provides full-screen
images from up to 16 analog cameras. Multiplexers can playback everything
that happened on any one camera with no interference from the other
cameras on the system.
Network connectivity - The physical (wired or wireless) and logical (protocol)
connection of a computer network or an individual device to a network, such
as the Internet or a LAN.
Noise -
NTSC (National Television System Committee) - NTSC is the television and
video standard in the United States. NTSC delivers 525 lines at 60
half-frames/second. - OEM (Original Equipment Manufacturer) - This is a
designation for companies that manufacture equipment which is then
marketed and sold to other companies under their own names.
PAL (Phase Alternating Line) - PAL is the dominant television standard in
Europe. PAL delivers 625 lines at 50 half-frames/second.
PEM (Privacy Enhanced Mail) - An early standard for securing electronic
mail. The PEM-format is often used for representing an HTTPS certificate or
certificate request.
Ping - Ping is a basic network program used diagnostically to check the
status of a network host or device. Ping can be used to see if a particular
network address (IP address or host name) is occupied or not, or if the host at
that address is responding normally. Ping can be run from e.g. the Windows
Command prompt or the command line in Unix.
PIRs - An electronic device used in some security alarm systems to detect
motion.
Pixel - A pixel is one of the many tiny dots that make up a digital image. The
color and intensity of each pixel represents a tiny area of the complete image.
PoE (Power over Ethernet) - Power over Ethernet provides power to a
network device via the same cable as used for the network connection. This is
very useful for IP-Surveillance and remote monitoring applications in places
where it may be too impractical or expensive to power the device from a
power outlet.
PPP (Point-to-Point Protocol) - A protocol that uses a serial interface for
communication between two network devices. For example, a PC connected
by a phone line to a server.
PPTP (Point-to-Point Tunnelling Protocol) - A protocol (set of
communication rules) that allows corporations to extend their own corporate
network through private "tunnels" over the public Internet. In this way a
corporation can effectively use a WAN (Wide Area Network) as a large single
LAN (Local Area Network). This kind of interconnection is known as a virtual
private network (VPN).
Pre/post alarm images - The images from immediately before and after an
alarm. These images are stored in a buffer for later retrieval.
Progressive scan - Progressive scan, as opposed to interlaced video, scans the
entire picture, line by line every sixteenth of a second. In other words,
captured images are not split into separate fields as in interlaced scanning.
Computer monitors do not need interlace to show the picture on the screen,
but instead show them progressively, on one line at a time in perfect order,
i.e. 1, 2, 3, 4, 5, 6, 7 etc., so there is virtually no "flickering" effect. In a
surveillance application, this can be critical when viewing detail within a
moving image, such as a person running. A high-quality monitor is required
to get the best from progressive scan. See also Interlacing.
Protocol - A special set of rules governing how two entities will
communicate. Protocols are found at many levels of communication, and
(streaming media) and CD distribution, conversational (videophone), and
broadcast television.
Most of the features included in MPEG-4 are left to individual developers to
decide whether to implement them or not. This means that there are probably
no complete implementations of the entire MPEG-4 set of standards. To deal
with this, the standard includes the concept of "profiles" and "levels",
allowing a specific set of capabilities to be defined in a manner appropriate
for a subset of applications.
Multicast - Bandwidth-conserving technology that reduces bandwidth usage
by simultaneously delivering a single stream of information to multiple
network recipients.
Multiplexer - A multiplexer is a high-speed switch that provides full-screen
images from up to 16 analog cameras. Multiplexers can playback everything
that happened on any one camera with no interference from the other
cameras on the system.
Network connectivity - The physical (wired or wireless) and logical (protocol)
connection of a computer network or an individual device to a network, such
as the Internet or a LAN.
Noise -
NTSC (National Television System Committee) - NTSC is the television and
video standard in the United States. NTSC delivers 525 lines at 60
half-frames/second. - OEM (Original Equipment Manufacturer) - This is a
designation for companies that manufacture equipment which is then
marketed and sold to other companies under their own names.
PAL (Phase Alternating Line) - PAL is the dominant television standard in
Europe. PAL delivers 625 lines at 50 half-frames/second.
PEM (Privacy Enhanced Mail) - An early standard for securing electronic
mail. The PEM-format is often used for representing an HTTPS certificate or
certificate request.
Ping - Ping is a basic network program used diagnostically to check the
status of a network host or device. Ping can be used to see if a particular
network address (IP address or host name) is occupied or not, or if the host at
that address is responding normally. Ping can be run from e.g. the Windows
Command prompt or the command line in Unix.
PIRs - An electronic device used in some security alarm systems to detect
motion.
Pixel - A pixel is one of the many tiny dots that make up a digital image. The
color and intensity of each pixel represents a tiny area of the complete image.
PoE (Power over Ethernet) - Power over Ethernet provides power to a
network device via the same cable as used for the network connection. This is
very useful for IP-Surveillance and remote monitoring applications in places
where it may be too impractical or expensive to power the device from a
power outlet.
PPP (Point-to-Point Protocol) - A protocol that uses a serial interface for
communication between two network devices. For example, a PC connected
by a phone line to a server.
PPTP (Point-to-Point Tunnelling Protocol) - A protocol (set of
communication rules) that allows corporations to extend their own corporate
network through private "tunnels" over the public Internet. In this way a
corporation can effectively use a WAN (Wide Area Network) as a large single
LAN (Local Area Network). This kind of interconnection is known as a virtual
private network (VPN).
Pre/post alarm images - The images from immediately before and after an
alarm. These images are stored in a buffer for later retrieval.
Progressive scan - Progressive scan, as opposed to interlaced video, scans the
entire picture, line by line every sixteenth of a second. In other words,
captured images are not split into separate fields as in interlaced scanning.
Computer monitors do not need interlace to show the picture on the screen,
but instead show them progressively, on one line at a time in perfect order,
i.e. 1, 2, 3, 4, 5, 6, 7 etc., so there is virtually no "flickering" effect. In a
surveillance application, this can be critical when viewing detail within a
moving image, such as a person running. A high-quality monitor is required
to get the best from progressive scan. See also Interlacing.
Protocol - A special set of rules governing how two entities will
communicate. Protocols are found at many levels of communication, and
there are hardware protocols and software protocols.
Proxy server - In an organization that uses the Internet, a proxy server acts
as an intermediary between a workstation user and the Internet. This provides
security, administrative control, and a caching service. Any proxy server
associated with a gateway server, or part of a gateway server, effectively
separates the organization’s network from the outside network and the local
firewall. It is the firewall server that protects the network against outside
intrusion.
A proxy server receives requests for Internet services (such as Web page
requests) from many users. If the proxy server is also a cache server, it looks
in its local cache of previously downloaded Web pages. If it finds the page, it
is returned to the user without forwarding the request to the Internet. If the
page is not in the cache, the proxy server, acting as a client on behalf of the
user, uses one of its own IP addresses to request the page from another server
over the Internet. When the requested page is returned, the proxy server
forwards it to the user that originally requested it.
P-VOP - See VOP.
Resolution - Image resolution is a measure of how much detail a digital
image can hold: the greater the resolution, the greater the level of detail.
Resolution can be specified as the number of pixel-columns (width) by the
number of pixel-rows (height), e.g. 320x240.
Alternatively, the total number of pixels (usually in megapixels) in the image
can be used. In analog systems it is also common to use other format
designations, such as CIF, QCIF, 4CIF, etc.
RTCP (Real-Time Control Protocol) - RTCP provides support for real-time
conferencing of groups of any size within an intranet. This support includes
source identification and support for gateways like audio and video bridges as
well as multicast-to-unicast translators.
RTCP offers quality-of-service feedback from receivers to the multicast group
as well as support for the synchronization of different media streams.
RTP (Real-Time Transport Protocol) - RTP is an Internet protocol for the
transport of real-time data, e.g. audio and video. It can be used for
media-on-demand as well as interactive services such as Internet telephony.
RTSP (Real Time Streaming Protocol) - RTSP is a control protocol, and a
starting point for negotiating transports such as RTP, multicast and Unicast,
and for negotiating codecs.
RTSP can be considered a "remote control" for controlling the media stream
delivered by a media server. RTSP servers typically use RTP as the protocol for
the actual transport of audio/video data.
Router - A device that determines the next network point to which a packet
should be forwarded on its way to its final destination. A router creates
and/or maintains a special routing table that stores information on how best
to reach certain destinations. A router is sometimes included as part of a
network switch. See also switch.
Server - In general, a server is a computer program that provides services to
other computer programs in the same or other computers. A computer
running a server program is also frequently referred to as a server. In practice,
the server may contain any number of server and client programs. A Web
server is the computer program that supplies the requested HTML pages or
files to the client (browser).
Sharpness - This is the control of fine detail within a picture. This feature was
originally introduced into color TV sets that used notch filter decoders. This
filter took away all high frequency detail in the black and white region of the
picture. The sharpness control attempted to put some of that detail back in the
picture. Sharpness controls are mostly superfluous in today's high-end TVs.
The only logical requirement for it nowadays is on a VHS machine.
Simplex - In simplex operation, a network cable or communications channel
can only send information in one direction.
SMTP (Simple Mail Transfer Protocol) - SMTP is used for sending and
receiving e-mail. However, as it is "simple," it is limited in its ability to queue
messages at the receiving end, and is usually used with one of two other
protocols, POP3 or IMAP. These other protocols allow the user to save
messages in a server mailbox and download them periodically from the
server.
SMTP authentication is an extension of SMTP, whereby the client is required
to log into the mail server before or during the sending of e-mail. It can be
used to allow legitimate users to send e-mail while denying the service to
Proxy server - In an organization that uses the Internet, a proxy server acts
as an intermediary between a workstation user and the Internet. This provides
security, administrative control, and a caching service. Any proxy server
associated with a gateway server, or part of a gateway server, effectively
separates the organization’s network from the outside network and the local
firewall. It is the firewall server that protects the network against outside
intrusion.
A proxy server receives requests for Internet services (such as Web page
requests) from many users. If the proxy server is also a cache server, it looks
in its local cache of previously downloaded Web pages. If it finds the page, it
is returned to the user without forwarding the request to the Internet. If the
page is not in the cache, the proxy server, acting as a client on behalf of the
user, uses one of its own IP addresses to request the page from another server
over the Internet. When the requested page is returned, the proxy server
forwards it to the user that originally requested it.
P-VOP - See VOP.
Resolution - Image resolution is a measure of how much detail a digital
image can hold: the greater the resolution, the greater the level of detail.
Resolution can be specified as the number of pixel-columns (width) by the
number of pixel-rows (height), e.g. 320x240.
Alternatively, the total number of pixels (usually in megapixels) in the image
can be used. In analog systems it is also common to use other format
designations, such as CIF, QCIF, 4CIF, etc.
RTCP (Real-Time Control Protocol) - RTCP provides support for real-time
conferencing of groups of any size within an intranet. This support includes
source identification and support for gateways like audio and video bridges as
well as multicast-to-unicast translators.
RTCP offers quality-of-service feedback from receivers to the multicast group
as well as support for the synchronization of different media streams.
RTP (Real-Time Transport Protocol) - RTP is an Internet protocol for the
transport of real-time data, e.g. audio and video. It can be used for
media-on-demand as well as interactive services such as Internet telephony.
RTSP (Real Time Streaming Protocol) - RTSP is a control protocol, and a
starting point for negotiating transports such as RTP, multicast and Unicast,
and for negotiating codecs.
RTSP can be considered a "remote control" for controlling the media stream
delivered by a media server. RTSP servers typically use RTP as the protocol for
the actual transport of audio/video data.
Router - A device that determines the next network point to which a packet
should be forwarded on its way to its final destination. A router creates
and/or maintains a special routing table that stores information on how best
to reach certain destinations. A router is sometimes included as part of a
network switch. See also switch.
Server - In general, a server is a computer program that provides services to
other computer programs in the same or other computers. A computer
running a server program is also frequently referred to as a server. In practice,
the server may contain any number of server and client programs. A Web
server is the computer program that supplies the requested HTML pages or
files to the client (browser).
Sharpness - This is the control of fine detail within a picture. This feature was
originally introduced into color TV sets that used notch filter decoders. This
filter took away all high frequency detail in the black and white region of the
picture. The sharpness control attempted to put some of that detail back in the
picture. Sharpness controls are mostly superfluous in today's high-end TVs.
The only logical requirement for it nowadays is on a VHS machine.
Simplex - In simplex operation, a network cable or communications channel
can only send information in one direction.
SMTP (Simple Mail Transfer Protocol) - SMTP is used for sending and
receiving e-mail. However, as it is "simple," it is limited in its ability to queue
messages at the receiving end, and is usually used with one of two other
protocols, POP3 or IMAP. These other protocols allow the user to save
messages in a server mailbox and download them periodically from the
server.
SMTP authentication is an extension of SMTP, whereby the client is required
to log into the mail server before or during the sending of e-mail. It can be
used to allow legitimate users to send e-mail while denying the service to