Difference between revisions of "Terminology"

Latest revision as of 18:05, 15 August 2016

4K

3840 pixels × 2160 lines UHD [Ultra High Definition]

720P

1280 pixels × 720 lines HD [High Definition]

8K

7680 pixels × 4320 lines FUHD [Full Ultra High Definition]

960H

960H is a new video standard for security systems that provides high resolution images using new advanced image sensors. Security cameras capable of 960H produce an image that is 960x480 compared to 702x480 for D1 and 352x240 for CIF.

1080P

1920 pixels x 1080 lines FHD [Full High Definition]

ACCESS CONTROL

The ability of restriction access to certain areas.

Alarm Input

Some DVRs and security cameras have alarm inputs, which can accept input from a sensor device such as a door contact or a passive infra-red motion detection which trigger the camera or DVR to take some action such as to begin recording.

Aperture

Controls how much light can go through the lens and sensor.

ATM

Automated teller machine

POS

Point of Sale, the place at which the goods are retailed.

Balun

A Video Balun enables the transmission of video using unshielded twisted pair wire instead of coaxial cable. The word "balun" comes from combining the terms balanced and unbalanced. The function of a balun is to transform an unbalanced signal into a balanced signal. When video signal is transmitted through coaxial cable, the distance traveled by the signal is limited because the signal is in the form of an unbalanced signal that is susceptible to Radio Frequency Interference or noise. Coax cable incorporates special shielding to minimize noise. Video Baluns transform the video signal into a balanced form in which each wire in the twisted pair transmits an identical signal with opposite polarized magnetic fields. Noise affects each signal equally. When the signals are combined, the noise is cancelled out. By using a designed balun, an unshielded twisted pair wire can transmit video for much longer distances than coax cable and with a lower cable cost

Bitrate

Byte transfer speed for every second it transfers. The unit is bps(bit per second).The higher the bitrate is, the more data it can transfer.

Blind zone

The area which is not detected in the image.

BNC Connector

BNC is a connector for coaxial cable that is most commonly used for CCTV installations.

Constant Bit Rate

CBR

Fixed sample rate compression. The advantage is fast compression, can be supported by most software and device, the disadvantage is the relatively large space

DAS

Direct Attached Storage

The traditional method of locally attaching storage devices to servers via a direct communication path between the server and storage devices. For more information, click this.

DDNS

Dynamic Domain Name Service

A method of automatically updating a name server in the Domain Name System (DNS), often in Not Real Time, with the active DDNS configuration of its configured host names, addresses or other information. The term is used to describe two different concepts.

DECODE

This is a device, circuit, program, algorithm the would covert information from one media format to another. This would be the purpose of standardization, speed secrecy or comparison. The input signal to a video decoder is analog video that conforms to a standard format such as NTSC or PAL.

Definition of Internet

Wikipedia - The Internet is a large group of computers that are connected to each other. The Internet is used to send information quickly between computers around the world. It has millions of smaller domestic,academic, business, and government networks and websites, which together carry many different kinds of information (facts and details) and services. So in other words, the Internet is a network of networks.

Detection area

The area which is needed to be detected in the image.

Distance of network cable

We use the fiber to connect the countries. We only use network cable when it reaches to final clients. So it mainly depends on the fiber to communicate.

DOF calibration

rebuild environment 3-D information.

DVR

Digital Video Recorder.

EIS

Electronic image stabilization

Electronic image stabilization-ensures image is clear even if the camera is moving.

ENCODER

this is a device, circuit, program, alogorithm the would covert information from one media format to another. This would be the purpose of standarization, speed secrecy or comparision.

EVS

Embedded Video Storage

EXTRA STREAM

This is the secondary or third video output stream for access the DVR/NVR/IP Camera system from a remote location.

Failed alarm

it meets the rule condition but fails to trigger alarm.

False alarm

False alarm caused by interference source (light change, leaf waggling, rain & snow, small animals)

Field of view

The overall image displayed by the camera.

FTP

Termed as File transfer protocol, it is a network protocol for transfering files from one point to another over the TCP based network, ie: the internet.

H.264

The intent of the H.264/AVC project is to create a standard capable of providing good video quality at substantially lower bit rates than previous standards, without increasing the complexity of design so much that it would be impractical or excessively expensive to implement.

HD

FHD

UHD

FUHD

HD is an abbreviation for High Definition and typically refers to resolutions that are higher than 1280x720. The most common formats are 720P/HD, 1080P/Full HD, 4K/UHD and 8K/FUHD

HDCVI

In November 2012, Dahua technology released analog high-definition transmission interface technology-HDCVI（High Definition Composite Video Interface）, with self-owned intellectual property right. HDCVI technology is a HD video transmission method, based on existing RG-59 or RG-6 coaxial cable. It can achieve long distance HD video signal reliable transmission at low cost via low general coaxial cable. In the practical application, HD-SDI subsystem requires high transmission medium, while HDCVI is suitable to the long distance, low cost transmission medium and complex deployment situation.

HEVC

H.265

Also known as High Efficiency Video Coding, is a successor to H.264 (MPEG-4) and saves 50% bandwidth & HDD also supports 4K with 4ch@7fps or 1ch@30fps.

HDD

Also known as Hard Disk Drive, it is a device that would store files like documents or in our case video recorded files as a digital file.

I Frame Interval

the interval time between every two I frame, I-frame is called intra-picture, P-frame is called prediction picture. I-frame need more space and the best image quality.An I frame is an 'Intra-coded picture', in fact a fully specified picture, like a conventional static image file. P frames and B frames hold only part of the image information, so they need less space to store than an I frame and thus improve video compression rates.

IP 66

IP code (Ingress Protection) that indicates the degree of protection provided by enclosures for electrical equipment. The first number indicates protection of internal equipment against the ingress of solid foreign objects. The second number indicates protection of internal equipment against harmful ingress of water. Higher digits refer to higher levels of protection

IP Cam (Network Camera)

IPC

IP Camera

Network Camera

An Internet protocol camera, or IP camera, is a type of digital video camera commonly employed for surveillance, and which, unlike analog closed circuit television (CCTV) cameras, can send and receive data via a computer network and the Internet.

IR LEDs

Illuminates image in the night. Infrared light emitted by the light, wavelength of 850nm and 940nm, are not visible , energy saving, the past 10 years, it has been widely used in the field of security monitoring

ISCSI

IP Small Computer System Interface.

IVS

Intelligent Video Surveillance-Estimate the camera’s internal parameters (including internal geometric features, optical features) and external parameters (the camera’s 3D location and direction relative to the real coordinate system) according to one horizontal line and three altitude lines calibrated by users, then confirm the corresponding relations between the 2D image captured by the camera and real 3D object.

LAN

Local Area Network

A local area network (LAN) is a group of computers and associated devices that share a common communications line or wireless link. For example, an enterprise network is generally a local area network. A network of large-scale video surveillance project is a local area network.

LUX

Unit of light illuminance used as a measure of low-light recording capacity in security cameras. Cameras with a Lux rating of 0.2 Lux or less would be considered low-light cameras. It is not possible to get good color definition in low light levels, so in general low light cameras are always black and white. Day/night cameras use electronics to switch from color during the daytime, to black/white during night or low light conditions. Many low light cameras also use infrared, which is useful in zero light conditions. The lower the LUX rating of a camera, the better it will see in low light.

MAC Address

MAC is the ID of the computer. Each computer has its own identity. It is unique around the world. The Mac address is binding with the device once it is produced. Usually we do not modify it. Of course, we can use COM to change its setup.

MAIN STREAM

This is the main video output stream feeds for the camera or channels that is for a local remote use, meaning within network.

Minumum Illumination

Min Illumination

Minimum illumination is a parameter to show the camera‘s performance in the night or low light scene. The smaller the value is ,the higher the sensitivity of the sensor is.

MJPEG

M-JPEG

Motion JPEG

Motion JPEG (M-JPEG or MJPEG) is a video compression format in which each video frame or interlaced field of a digital video sequence is compressed separately as a JPEG image.

Multicast

It is to allow the NVR/DVR to work more efficently by steaming one access feed and letting the Router device distribute the video feed to multiple devices.

NAS

Network Attached Storage

a file-level access storage architecture with storage elements attached directly to a LAN. For more information, click this.

NTSC

National Television System Committee, is the video system or standard used in North America and most of South America. NTSC, 30 Frames are being transmitted each second.

NVR

Network Video Recorder.

ONVIF

A global and open industry forum with the goal to facilitate the development and use of a global open standard for the interface of physical IP-based security products. Or in other words, to create a standard for how IP products within video surveillance and other physical security areas can communicate with each other

ONVIF/PSIA

PSIA

These protocol regulate the function of application interface. By these protocol, not only DAHUA IPC could be accessed to DAHUA NVR, but also others brands that support ONVIF or PSIA. And all over network devices, which support ONVIF or PSIA, could communicate each other.

OSD (On Screen Display)

A method or on screen menu of displaying set-up information and/or instructions on a display monitor.

PAL

PAL is an abbreviation for Phase Alternating Line. This is the television display standard that is used mainly in Europe, China, Malaysia, Australia, New Zealand, the Middle East, parts of Africa, and other parts of the world. PAL uses 625 lines per frame and a frame rate of 25 frames per second.

P2P

Is a network point to point access without compromising the Router or modem's firewall.

Power over Ethernet

POE

Power over Ethernet. By this technology, we could transmit the network signal not only with single cable, but also the power supply. (MAX. Distance 100 Meter)

PreRecord

Pre-Record

You can set pre-record time(from 1-30s), this function can extend the life of HDDs and help to analysis MD/Alarm video( you can refer the event part )

PTZ

An acronym for Pan Tilt and Zoom.

RS-232

RS-232 is a communications standard for serial communications between devices. In CCTV, this can be communication between a contoller and a surveillance camera. The RS-232 standard allows for the connection of two devices through a serial link, and is the protocal used for serial connections in computers. RS-485 allows for serial connections between more than 2 devices on a networked system and is defined below.

RS-485

RS485, also referred to as EIA-485 is a communications standard for serial communication between devices. When talking about surveillance systems, RS-485 is typically used as the protocal to allow computers and remote controllers to control the activity of cameras such as pan, tilt, rotate, and zoom operations. RS485 is an updated version of the original serial protocol, RS-232.

RAID

Known as Redundant Array of Independent Disks, a technology that is used to increase the performance and/or reliability of data storage.

Resolution

The resolution of a camera is often limited by the image sensor that turns light into discrete signals. The brighter the image at a given point on the sensor, the larger the value that is read for that pixel.

ROI

Region of Interest- allows cameras to enhance image quality of region of interest by decreasing non-ROI’s image quality to acquire more computing power and bandwidth.

RTSP

Real time Streaming Protocol is a network protocol that was designed for the use in Entertainment and Video Communication systems to control the video servers. The use was for the establishment and controling media sessions between the two points.

SAN

Storage Area Network

A network that provides access to consolidated, block level data storage. For more information, click this.

Sensitivity

The difficulty level of target detection and alarm, the higher the sensitivity is, the easier it is to detect, but with more false alarms; the lower the sensitivity is, the less false alarm will be, but with more failed alarms.

Size filter

Only reserve the target which meets the requirement of size (width height/area) and aspect ratio.

Smart detection

tripwire, intrusion detection, abandoned/missing, scene change, defocus, facial detection and audio detection, allowing automatically detect under rulemaking and trigger alarms, accordingly.

Signal to Noise Ratio (S/N Ratio)

This is the ratio between the signal strength and the noise levels on an audio or video signal.

SD

An abbreviation for Speed Dome, could also mean Standard Definition depending on who you ask and in what context.

SSD

Solid State Drive, a solid-state storage device that uses integrated circuit assemblies as memory to store data persistently.

SUB STREAM

This is the secondary or third video output stream for access the DVR/NVR/IP Camera system from a remote location.

Sub-g

Also known as Sub-GHz is a wireless technology using IQRF for wireless packet-oriented communication via radio frequency that is used in Access Control Systems. It transfer frequencies between 27MHz-960 MHz, most commonly used are 433MHz and 915MHz.

Target

Moving object with some certain type (such as human, vehicle and etc.) which appears in the field.

TCP/UDP

TCP

UDP

These protocol regulate the transmission method of network signal of IP equipments. By these protocol, we realized our DAHUA IPC to access our DAHUA NVR, and all over the DAHUA network devices could communicate each other.

Tripwire Function

Only applied to the scene where the targets are sparse and there is rarely any covering between targets, such as the perimeter without any guard. It will trigger alarm when the target passes through the warning line according to the set movement direction. It takes some time from the target appears to the target is confirmed, so it needs to leave some space when setting warning line, do not set it near the covering. Detect if there is any object crossing the warning line, it can support different direction selection, such as A->B, B->A and bidirectional, and it can activate record , snapshot and alarm according to the judgment result.

Variable Bit Rate

VBR

without a fixed bit rate, in the compression software, determined by the instant video data bit rate, quality taking into account.

Varifocal (Zoom)

This refers to a type of lens that has the capability to change the focal length. This allows adjustment of the magnification and field of view of the security camera.

WDR (Wide Dynamic Range)

Used for capturing clear images of objects surrounded by a strong back light, while still keeping the background visible.