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CCTV Explained – What It All Means

CCTV Explained - What It All Means

The odds are pretty high that if you’re new to using CCTV or are on the market for a system, you’ve had a metric ton of acronyms and phrases thrown at you.

CCTV Systems Explained

“WDR? IR? BLC? NVR? DVR? POE? What does it all mean?!” When you start shopping around for security equipment, regardless of whether it’s for your home or business you have to get the lay of the land before you make a decision. How else are you going to know if a CCTV system is right for you if you don’t know what it does?

Don’t worry, we have all been there. We demystify the technical jargon and help our customers choose the right hardware and software for their specific needs – each home and business is different.

We have put together the most commonly used terms and acronyms in this CCTV Systems glossary to help our customers in making informed decisions about your security needs. This is by no means an exhaustive list but does cover the most commonly used equipment.

Our glossary contains a list of general terms and definitions related to surveillance systems, security cameras, and CCTV equipment. If you find any terms on our web site that you do not understand and can not find in this glossary, please reach out to us and we will be happy to give you any technical information or advice.


(Auto Back Focus) technology allows cameras to adjust the position of the image sensor to obtain optimal focus.

NVRs (Network Video Recorders) with the ANR (Automatic Network Replenishment) function can automatically store video data on the IPC (Internet Protocol Camera) storage card when the network is disconnected. After recovery of the network, the NVR automatically retrieves the video data stored on the camera.

Audio Loss Detection
Alarm actions or notifications will be triggered when there is audio loss.

Backlight Compensation compensates for the luminance of video captured in a backlit environment, while maintaining the luminance of the overall video sequence. Simply put, BLC enables objects that appear dark to be visible against a very bright background such as in front of a window or shop entrance. BLC is usually effective for some specific region in the video, as the background is usually overexposed.

Digital Image System cameras are a new series of analog entry-level products. With excellent image quality, low power consumption, and high reliability, DIS cameras can provide a perfect cost-effective alternative to traditional analog cameras.

By modeling the imaging features of smoke, dust, fog, etc., defog technology effectively restores details and colour to obtain accurate and natural video. Defog technology helps maintain clarity in images captured in poor weather conditions such as rain, smog, or fog.

Digital Watermark
Digital watermark technology embeds the device information onto recorded video. Digital watermarks may be used to verify the authenticity or integrity of the video or to show the identity of its owners.

Defocus Detection
Alarm actions will be triggered when the camera is out of focus.

Dynamic Adjustment of Encoding Parameters
The user adjusted encoding parameters can take effect at once without pausing or restarting of network transmitting and recording. In the CCTV System, for a static monitoring scene, video can be recorded in low bit rate through reducing resolution, image quality, bit rate and frame rate, while changing of image scene requires higher resolution, bit rate and frame rate of video, etc to get high quality video stream. Since the above parameters can be dynamically modified, continuous images can be maintained without switching files frequently. And it does not only meet the requirement of high-quality images at critical moments, but also save the disk space and network bandwidth.

Double Common Intermediate Format, a format of color images whose resolution is 528 x 384 pixels (PAL) or 528 x 320 pixels (NTSC)

3D digital noise reduction provides images with less noise in low-light surveillance scenes compared to conventional cameras. 3D DNR can be used to enhance image quality and save bandwidth.

EZVIZ is a video-service application designed especially for consumer markets. EZVIZ incorporates the following key features:
1) Easy P2P access: easy to use, no port mapping configuration required
2) Private network penetration: solves the problems of private IP address and DDNS shortage
3) Value-added service: push alarm, two-way audio, etc.
EZVIZ can be used in business scenarios for safeguarding or in residences for the elderly or other vunrable individuals. We provide free EZVIZ apps, available on iOS and Android.
For more information, please go to www.ezviz7.com.

In conditions with slight vibrations (e.g., an electrical pole in strong winds), videos will appear fuzzy due to the vibration. EIS (Electronic Image Stabilisation) can help reduce the effects of vibration in a video.

Face Detection
With face detection technology, a 4-line network camera can accurately detect human faces, capture facial images, or trigger an alarm.

HDD Group
HDD (Hard Disk Drive) Group mode is one of the storage modes in DVRs/NVRs. Multiple HDDs can be managed in groups. Video from specified channels can be recorded onto a certain HDD group through HDD settings

HDD Quota
Each camera can be configured with an allocated quota of HDDs to store recorded files.

Heat Map
The video surveillance heat map records the motion of customer foot traffic over a period of time and displays temporal density and spatial statistics in different colours. For instance, red shows the areas customers most frequently visited and tended to stay longer, and blue reflects otherwise. Heat map is ideal for use in locations such as supermarkets, retail stores, etc., to help businesses identify the most popular merchandise and where to place products in order to increase sales.

HiDDNS is a FREE dynamic domain name server provided by Hikvision, which offers a persistent domain name for non-static IP devices. DDNS technology is widely used in various Hikvision devices (e.g., DVR, NVR, IPC, etc.) without having to register for a third-party domain name. When you register the service, you can use a fixed domain name to access your devices that have a dynamic IP address.

In conditions with a strong light source towards the camera, there will be over-exposed areas, or “high light.” The HLC (High Light Compensation) function can automatically recognise and constrain the high light to make objects more distinguishable.

HD-TVI (High Definition Transport Video Interface) is an open standard for analog video transmission and is based on the original analog transmission media. The advantages of HD-TVI are:
1) Farther transmission distance
2) Higher video resolution
3) Reliable anti-interference performance as it carries low-frequency signal

Cameras with ICR (IR Cut filter Removable) function have a mechanical IR filter that filters infrared light during the day to correct color casts caused by infrared light. At night the camera removes the filter automatically to let infrared light pass through, enhancing night visibility.

Intrusion Detection
Intrusion detection is a behavior analysis function. If a person enters and loiters in a pre-defined virtual region, the camera will automatically detect the event and can trigger alarms or recording if pre-configured. By applying the latest algorithm, it automatically analyses the intruder’s dimension ratio to reduce false alarms. Intrusion detection is extremely beneficial for defined area protection.

Low Bit Rate
By applying an advanced codec (compressor/decompressor) algorithm, our range of Smart IP cameras can realise efficient encoding and further minimise the system’s load and storage requirements. At a very low bit rate streaming condition, 720p resolution at a 2 Mbps bitrate, cameras are able to increase the image quality up to 30 percent.

Line Crossing Detection
If a person crosses a pre-defined virtual line, the camera will automatically detect the event and can trigger alarms or recording if pre-configured to do so.

Motion Detection
If there is any motion in the configured detection area, the camera will automatically detect the event and can trigger preconfigured alarms or recording. Our customers can set sensitivity level, detection area, and arming schedule accordingly.

Multi-Address Mode
Multi-address mode is an NVR (Network Video Recorder) function on networks with more than one NIC (Network Interface Controller). Each NIC works independently with separate parameter settings, which can be assigned with a different IP address in a different network. Multi-address mode can be used to establish network isolation.

Net-Fault Tolerance Mode
Net-Fault Tolerance Mode is an NVR (Network Video Recorder) function on networks with more than one NIC (Network Interface Controller). All the NICs use the same IP address. If a working NIC breaks down, others will continue to work and the NVRs’ network connection is not affected.

N+1 Hot Spare
N+1 hot spare protects the system against NVR (Network Video Recorder) network failures. When an NVR fails to connect to the network, a hot spare NVR will take its place to ensure data integrity and reliability. After the failed NVR is online, the hot spare NVR will send the data back to the working NVR.

Object Removal Detection
If objects are removed from a pre-defined region, such as exhibits on display, the camera will automatically detect the event and can trigger alarms or recording if pre-configured.

People Counting
Cameras with the people counting function are usually installed vertically to the entrance gate of hotels, supermarkets, museums, etc. The number of people that enter and exit the room can be counted and displayed on the screen in real time.

Privacy mask
Privacy mask is used to block or mask certain areas of a scene from viewing and recording to protect privacy such as neighbouring house windows.

The 4-line Smart IP camera adopts the most advanced iris control technology, P-iris, which allows for keeping accurate and consistent sharpness and depth of view.

In some surveillance scenarios, users pay special attention only to a certain region instead of the entire image. The region that attracts special attention is known as the region of interest, or ROI. The ROI encoding method was developed to provide different compression levels between the ROI and background information in order to capture clearer key information without increasing the overall bitrate. The application of ROI encoding technology helps to conserve bandwidth and optimise the bitrate resource allocation, thus ensuring the image quality of the region of interest.

Redundant Array of Independent Disks is a storage technology that combines multiple disk drive components into a logical unit. A RAID setup stores data over multiple hard disk drives to provide enough redundancy so that data can be recovered if one disk fails. Data is distributed across the drives in one of several ways called “RAID levels,” depending on what level of redundancy and performance is required.

Rotate Mode
In a vertically-shaped location such as a hallway or corridor, a horizontal-shaped image could result in pixel wastage. Rotate Mode can change the image from horizontal to vertical, so as to maximize pixel usage and avoid wasting bandwidth and storage space.

Region Entrance
If someone enters a pre-defined virtual region, the camera will automatically detect the event and can trigger alarms or recording if pre-configured.

Region Exiting
If someone exits from a pre-defined virtual region, the camera will automatically detect the event and can trigger alarms or recording if pre-configured.

Smart IR
The improved Smart IR function adjusts the IR strength to have better visibility depending on specific requirements. Smart IR is usually used to solve the problem of IR over-exposure in close shots.

Smart Tracking
The Smart Tracking function is an innovative technology for PTZ cameras, which can enhance the effectiveness of the CCTV video surveillance system. In surveillance scenes where the occasional presence of people or vehicles require special attention (e.g., bank vaults, hotel corridors, car parks etc.), smart tracking can be used to detect moving objects and follow their movements until they’re out of view.

Scene Change Detection
If someone changes the camera’s viewing direction so that the camera captures a different scene, the camera will automatically detect the event and can trigger alarms or recording if pre-configured.

Smart Playback
Smart Playback provides an easy way to go through less important information quickly. In Smart Playback mode, the system will analyse the video containing the motion or VCA (Video Content Analytics) information. The video with motion or VCA will be played at normal speed while the one without motion or VCA information will be played at up to 16-times speed. The Smart Playback rules and areas are configurable.

Sudden Audio Increase/Decrease Detection
If there is sudden audio change, either increase or decrease, the camera will automatically detect the event and can trigger alarms or recording if pre-configured.

Self-Monitoring Analysis and Reporting Technology is a monitoring system for HDDs to detect and report on various indicators of reliability in the hopes of anticipating failures.

Based on the HD-TVI standard. TurboHD enables reliable long-distance analog HD video transmission over coaxial cable. Analog users can enjoy HD without replacing their existing cabling structure and upgrading to IP. Also, TurboHD DVR supports self-adaptive access with normal analog cameras and TurboHD cameras. What’s more, TurboHD analog solutions offer seamless compatibility with various devices that adopt the HD-TVI standard as well.

Triple Streams
Triple streams provide much more flexibility to users by allowing different data streams to be sent simultaneously. Each stream has independent purposes:
• The first stream with high resolution and full frame rate can be used for main monitoring.
• The second stream with lower resolution can be used for mobile monitoring.
• The third stream with high, low, or dynamic resolution offers more flexible choices.

Transcoded Stream
Under situations with limited bandwidth, users can use a transcoded stream to lower the resolution, bitrate, and frame rate of the original bit stream to fulfill the needs of a low-bandwidth network and offer more solutions for remote monitoring.

Unattended Baggage
If an object(s) is removed from a scene (e.g., baggage, purse, dangerous materials, etc.), the camera will automatically detect the event and can trigger alarms or recording if so pre-configured.

Video Content Analysis is the capability to analyse video automatically to detect and determine temporal and spatial events. Many smart functionalities can be implemented in VCA such as intrusion detection, line crossing detection, etc.

Video Quality Diagnosis is a feature that monitors the video for abnormal qualities (i.e., blurred image, abnormal brightness, and color cast). An alarm will be triggered and linked with configured response actions.

Virtual Host
Virtual Host is an NVR (Network Video Recorder) function that lets users link directly to an IPC (Internet Protocol Camera)’s configuration Web page through their website browser. Virtual Host solves the issue of logging into an IPC when the IPC is on a different network from the NVR, making the system more convenient and user-friendly.

In conditions with very bright and dark areas, such as at an entrance door in an office building or an entranceway to an indoor parking garage or tunnel, a camera may capture over-exposed images in bright areas and under-exposed images in dark areas, which greatly affects image quality. A camera with WDR (Wide Dynamic Range) can help solve this issue. By combining images with short exposure (for bright areas) and long exposure (for dark areas) into one image, WDR technology captures both bright areas and dark areas clearly.

Zero Channel
For remote access, users are able to combine multiple channel videos into one zero channel and save transmission bandwidth.


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