دسته‌بندی نشده

cctv

دوربین مداربسته

CCTV

The objective of this document is to provide a reference against which Installers of CCTV systems, whether analogue, digital or a combination of these technologies, can be inspected to ensure that the functions and performance of CCTV systems installed by them are within levels agreed by the licensed contractor and the client or user of the CCTV system during the System Design phase of the process.

Definitions of cctv

CCTV system:

A system consisting of electronic or other devices designed constructed or adapted to monitor or record images on or in the vicinity of premises.

CCTV surveillance installation (installation):

An installation consisting of the hardware and software components of a CCTV system, fully installed and operational for monitoring on or in
the vicinity of premises.

نحوه نصب دوربین مداربسته

CCTV camera (camera):

A unit containing an imaging device producing a video signal from an optical image.

دوربین مداربسته با تشخیص حرکت

CCTV camera equipment:

A unit containing a CCTV camera plus appropriate lens and necessary ancillary equipment.

camera housing:

An enclosure to provide physical and/or environmental protection of the camera, lens and ancillary equipment.

محفظه دوربین مداربسته

client:

The purchaser of the CCTV system or representative(s) of the purchaser appointed for the purpose of purchasing the CCTV system.

data:

image, meta and other data of the CCTV system.

داده در دوربین مداربسته

documentation:

paperwork (or other media) prepared during the design, installation and hand over of the CCTV system, recording details of the CCTV system, including paperwork (or other media) related to maintenance (where applicable).

event:

incident in the real world.

EXAMPLE: A fire (burning house), an intrusion (broken door) or moving person, a power failure, a short circuit, an intruder passing into or into the vicinity of a premises.

export:

transfer of data from the original location to a secondary storage location with a minimum of necessary changes.

خروجی گرفتن از سیستم دوربین مداربسته

fault condition:

condition of the system which prevents the CCTV system or parts thereof functioning normally.

frame rate:

numbers of frames per second.

نرخ تصویر برداری دوربین مداربسته

illumination:

level of illumination on the area to be kept under surveillance.

روشنایی تصویر دوربین مداربسته

image:

visible representation of a frame as a rectangular grid of pixels.

interconnections:

means by which messages and/or signals are transmitted between CCTV system components.

اتصالات دوربین مداربسته

lens:

an optical device for projecting an image of a desired scene on to the photo-sensitive surface of the imaging device.

پوشش لنز دوربین مداربسته

notification:

passing an alarm or a message of the CCTV system to an external system.

operator:

authorised individual (a user) using a CCTV system for its intended purpose.

response:

every control command, change of system conditions or information to external devices or persons driven by alarms, faults, messages or triggers.

risk:

potential negative impact to an asset or value that may arise from some future event respecting the probability of loss.

surveillance:

observation or inspection of persons or premises for security purposes through alarm systems, CCTV systems, or other monitoring methods.

system components:

individual items of equipment which make up a CCTV system when configured together.

Uninterrupted Power Supply (UPS):

A device that provides battery backup in the event that the primary power source to an electrical system is interrupted, fails or falls below a level of power which is required for the operation of the electrical system in question. The UPS system may provide backup power for a period of minutes or several hours.

یو پی اس دوربین مداربسته

User:

authorised individual using a CCTV system for its intended purpose.

Overview

There is no theoretical limit to the number of cameras and monitors which may be used in a CCTV installation but, in practice, this will be limited by the efficient combination of control and display equipment and the operators’ ability to manage the system.

Location Survey

The criteria above will be determined by a location survey of the site where the CCTV system is to be installed. This location survey shall also take account of the following:
a) Risk
b) Contents
c) Building
d) Supervision levels

مکانسنجی دوربین مداربسته

The location survey shall have, at least, sufficient detail to address the security requirements of the client and shall lead to a site plan being prepared with the optimal positioning points for cameras being indicated on the site plan. The purpose of the location survey and site plan is to identify the best placings for cameras, the direction of natural light, potential and actual environmental problems.

System Design

The objectives of the system design stage are to determine the extent of the CCTV system; select the appropriate equipment and to prepare a system design proposal. The system design shall also be informed by the client’s and/or user’s requirements as to the purpose of the camera images.

Where the objective of the CCTV system design is solely for the purposes of observing images of persons or where this is among the objectives of the system design there is a relationship between the operator task and the size of the target (person) on the screen. If the target is a person and the CCTV system has an installed limiting resolution of better than 400 tv lines, the minimum sizes of the target1 shall be:

(i) for identification the target shall represent not less that 120% of screen height.
(ii) for recognition the target shall represent not less than 50% of screen height.
(iii) for detection the target shall represent not less than 10% of the picture height.
(iv) for monitoring (e.g. crowd control) the target shall represent not less than 5% of the picture height.

Where digital CCTV technology is used and the intended target is a person or persons the equivalent level of quality shall apply.

Figure 1 – Graphic Example of Clause 6.2 requirements

When designing the system, installers shall conduct a risk assessment to determine the risk level and shall also design the system paying attention to the function of the observation or surveillance as described by the client and/or user. The function of the observation or surveillance can include:

crowd control

theft

unauthorized entry

When designing a CCTV surveillance installation, the following criteria shall be taken into account under the headings Operational Requirements and documented in an easily understood and clear format:

Operational Requirements

a) Purpose(s) of the surveillance.
b) Potential threat or activity to be monitored and/or recorded.
c) Determination of the zones or objects requiring surveillance.
d) Determination of the number of cameras, and their locations, required to monitor the agreed zones and objects.
e) Intended target(s) of the surveillance and the frame rate appropriate to the target’s speed within the location under surveillance.
f) Response required on detection of an event.
g) Manner in which images will be viewed and recorded.
h) How data will be exported from the system to permanent record.
i) Individuals who will require access to the recorded data.
j) Selection of cameras and equipment depending on the operating environmental conditions.
k) Control centre configuration including secure location of control equipment.
l) Power supplies; the use of a mini UPS System should be considered in situations where there is no UPS in place.
m) Functional and operating procedures.
n) Maintenance and repair.
o) Evaluation of existing lighting and consideration of new or additional illumination including the use of Infra Red cameras or lamps.
p) Image resolution required.
q) Determination of the most appropriate transmission method to be utilized.
r) Compression technique to be used in recording (where appropriate).

The system design shall reflect the client’s and/or user’s instructions or requests regarding the system requirements including, where required, alert function(s), display, recording and export/archive.

An operational requirements form shall be completed for each camera in a CCTV System installation. Where cameras have identical operational requirements they may be grouped together on one form, providing the camera reference and location are included for each camera.

Where a CCTV system is installed and integrated with detectors, the following requirements shall be adhered to:

Detectors shall be installed in accordance with the requirements of I.S. EN 50131-1, as applicable. Manufacturer’s recommendations shall be complied with in the installation of cameras using video detection.

The range of any detector shall not be greater than the field of view of any associated camera.

The range of any detector should not cover any area outside of the site or location.

The position of any detector shall be chosen so that it is not adversely affected by the rising or setting of the sun.

Multiple detectors shall not be connected to a single input unless individually identified by the CCTV control equipment.

Where the location survey and system design documentation demonstrates that additional lighting is required and where this has been advised to, and agreed with, the client and/or user, the installation of such lighting shall be sufficient to illuminate the fields of view of each camera. The replacement of lighting shall be carried out in accordance with the manufacturer’s requirements.

System Design Proposal

A System Design Proposal shall be prepared for submission to the client. The proposal shall include the information detailed in Appendix 3. A sample System Design Proposal is included at Appendix 4.

The System Design Proposal may be subject to alteration at other stages in the implementation of the system. Any such changes shall be agreed between the licensed contractor and the client and/or user. In these cases the documentation shall be amended accordingly.

Installation Planning

Prior to commencing the installation of the components of the CCTV system, the following issues shall be considered.

Manufacturer’s recommendations

All system components shall be installed in accordance with the manufacturer’s recommendations. If installation of a component in accordance with the manufacturer’s recommendations is not possible, advice should be sought from the manufacturer or supplier.

Environmental considerations

System components shall be suitable for the environmental conditions in which they are to operate. Examples of environmental considerations include potential impact of changes in foliage from season to season, potential impact of daily and seasonal variations in light and climatic conditions.

CCTV Installation

Competence

The installation shall be carried out by installers with the necessary training and experience. Installers shall have the appropriate tools and test equipment necessary to install the CCTV system correctly. Where measuring equipment is used, the equipment must be of a standard necessary to provide the required precision and accuracy to install and test the system.

Prior to commencing work all relevant health and safety requirements shall be considered. These will vary with the nature of the premises and may involve special installation equipment when working in hazardous areas.

Electrical installation methods shall comply with current national and site regulations and the electrical installation shall be carried out by technicians who are qualified to the appropriate level.

Test and Commission

Inspection

An inspection of the system shall be carried out and documented on completion of the installation of the CCTV system to confirm that the CCTV system has been installed in accordance with the System Design Proposal. Any deviations shall be recorded for inclusion in the As Fitted Document. A sample Inspection Checklist is included at Appendix 5.

Functional testing

The CCTV system shall be tested and compared with the requirements included in the System Design Proposal as amended by the As Fitted Document.

As Fitted Document

A document shall be prepared, based upon the System Design Proposal, amended to reflect any changes to the CCTV design found to be necessary during the installation process. The As Fitted Document shall be an accurate record of the installed CCTV system including any information relating to the equipment installed and its location. A signed and dated copy of the As Fitted Document shall be given to the client after satisfactory completion of inspection and testing.

Maintenance

Regular preventative maintenance or servicing should be carried out to ensure that the CCTV system performs to the same level as pertained at the time of commissioning and hand-over of the system.

Maintenance, servicing and repair of CCTV systems shall only be carried out by a contractor in possession of a current, valid CCTV Installer’s licence issued by the PSA.

It is the client’s responsibility to arrange for the CCTV system to be properly maintained (inspected and serviced) and repaired as scheduled or necessary. A documented arrangement should be made between the client and a licensed company for the repair
and maintenance of the CCTV system. The arrangements shall specify the schedule of maintenance agreed including:

• the frequency of maintenance required,
• whether the maintenance is undertaken remotely or on-site, and
• the requirements of such maintenance

Preventative maintenance shall include the items contained in Appendix 6 of this document. The client shall be informed, in writing, of the date the maintenance was carried out and the identity of the person who carried out the maintenance.

Where any on-site maintenance is carried out, a documented record shall be signed by the maintenance technician/engineer and the client and/or user. Where any agreed remote maintenance is undertaken, the maintenance technician/engineer shall supply the client and/or user with details of the maintenance undertaken.

Where the person carries out agreed corrective or responsive maintenance, the client shall receive, in writing, a document

• outlining the fault condition requiring correction or repair,
• the actions taken to remedy the fault condition, and
• an undertaking that the system has been returned to the operational status pertaining before the fault condition occurred.

Modifications made to the CCTV installation or its configuration, shall be documented and notified in writing to the client and/or user and an inspection test shall be carried out on the relevant components or parts of the system.

Introduction

With the increasing concern over better protecting people and assets, security departments are required to provide a higher level of security than before: proactive prevention, better situational awareness, earlier detection, quicker identification and prompter action. Conducting well-planned surveillance, training security staff well and ensuring good communication between all related parties is essential. Video surveillance has also become essential. Now many organizations are continually reevaluating and enhancing their video surveillance to provide optimal daily security and operational efficiency.

If you are considering the enhancement of your analog video surveillance, upgrading your analog system with the latest IP technology will increase effectiveness and efficiency. A proper update plan avoids extra costs and unwanted problems, protecting your investment in the analog system. This paper provides guidelines for a successful upgrade and migration to a future-proof IP video surveillance system for Panasonic and non-Panasonic analog system users.

IP technology benefits

2.1 Market trend

Technology drives business success more than ever before. Open standard-based IP and High Definition (HD) video technologies definitely have had the greatest positive impact on video surveillance. Analog systems were good but IP systems are is the future. (The graph is created by Panasonic based on reliable information.)

2.2 Analog video surveillance
First, let’s examine the difference between analog and IP systems. The diagrams on the next page show typical analog systems. The indoor/outdoor analog cameras, analog monitors and Digital Video Recorders (DVRs) are connected to each other through an analog matrix switcher that switches video inputs to monitor outputs. Most DVRs for small systems have some switching functions as well as a recording function. Much coaxial cable is required to connect analog equipment. Analog video surveillance systems are simple, but they offer very limited functionality and expandability.

IP Video surveillance

IP system diagrams are similar to IP-based data networks such as corporate networks and the Internet. All equipment, such as indoor/outdoor IP cameras, is connected by Ethernet (LAN) cables. An IP Matrix Server or Video Management System (VMS) manages the whole system. IP video surveillance can be easily networked with other sites, mobile devices and other systems such as face recognition systems. In a small installation, most Network Video Recorders (NVRs) have some IP Matrix Server/VMS functions. The IP video surveillance systems are open, feature-rich, flexible, scalable and easy-to-use.

Analog, IP or composite solutions:

to identify the solution which is best suited to your requirements, you should:

  • define the areas of major safety concerns and detail what is to be monitored;
  • for each area that needs to be monitored define the detail of the images in question (image quality) and the level of lighting;
  • define the basic characteristics of the video cameras;
  • consider the advantages of a wired structure in regards to the traditional structure.

Small installation
Small business, car garage

ANALOG SOLUTION
1 VIDEO CAMERA
Plug&Play Kit

Small/medium installation
Business, parking

STANDARD :
ANALOG SOLUTION
The standard being from two
to sixteen video cameras

IP SOLUTION
for high resolution

Small/medium installation
Supermarket

MIXED SOLUTION
CCTV/IP with wire
structuring

Broad installation
Shopping centre

IP SOLUTION
With wire structuring

THE ADVANTAGE OF IP TECHNOLOGY
Thanks to high definition (HD et Full HD), a scene filmed in “recognition” mode can be zoomed to enable persons to be identified.

OBJECTIVES AND FUNCTIONS OF A CLOSED CIRCUIT TELEVISION SYSTEM

Guarding of property

Allowing an area to be open to the public while providing protection against theft in shops, car parks or enclosures.
The CCTV system facilitates live or delayed (when recording) monitoring of one or more areas of the building.

  • Enclosure, car park, sales area, etc.

Access monitoring

Monitoring access to buildings or premises outside opening hours can not only detect intrusions, but also trace incidents or malicious acts.
During periods when the building is in use, the CCTV system enables you to manage the opening of accesses by detecting the presence of a person near to an exit, or by working in conjunction with visitor access controls.

  • Recording access to a building

Event monitoring

When connected to other systems installed in a building or premises, the CCTV system can display the images from a camera associated with a specific event.

  • Intrusion: immediate verification and recording on detection of intrusion

  • Fire: verification of the presence of fire in the area concerned

  • Technical alarm: verification of a technical problem with the machinery

Filming

The main function of a camera is to film a scene live.

For example, it may be interesting to show customers in a shop that the premises are monitored by CCTV by visibly displaying the images on a screen connected directly to a camera. Besides being a deterrent, it allows shop workers to keep an eye on one or more scenes from a single location in the store.

Recording

Depending on the sensitivity of the scene to be visualized (or the type of building), it may also be necessary to save the images. This enables you to review the events that take place in order to better interpret them (in the case of shoplifting, for example).

Be careful not to fall into the trap of continuous recording: in addition to (relatively) quickly filling the hard drive, it also complicates the search for a specific event among the recordings.
Recordings should be programmed, as is relevant, focusing, for example, on access to the site during certain hours.

Visualizing and analyzing

Whether it is accessing the video channel for one or multiple recorders or accessing their recordings, it is possible to install dedicated video surveillance software at one or more locations (e.g. control station, police station, etc.).
Visualization can also be performed from a remote location using a smartphone or computer to enable monitoring at your leisure.

EXAMPLES OF IMPLEMENTATION OF A CLOSED CIRCUIT TELEVISION SYSTEM

Shops

This is to monitor and record just a few areas (usually the main entrance, product display area and cash register). An effective solution is offered by CCTV kits, expandable up to 4 cameras. Simple and discreet, thanks to their compact size, they allow remote viewing.

Supermarkets

This type of establishment necessitates the monitoring and video recording of numerous small and large areas, both internally and externally. The usual requirements for external areas are: surveillance of the stock loading/unloading area and car parks. The internal areas to be monitored are:

the product display areas, check out and warehouse. The solution is a bespoke design where all devices are monitored and controlled from a monitoring station.

Warehouses

This type of establishment necessitates the monitoring and video recording of various small and large areas, both internally and externally. The usual requirements for external areas are: surveillance of stock loading/ unloading areas, the sides of the building and parking lots. The internal areas to be monitored are: the warehouse and the loading/unloading area.

The solution is a bespoke design, where all devices are monitored and controlled from a local switchboard or a reception, with an operator present during the day. If necessary, it is possible to centralize the remote management of several sites.

SELECTION AND CHOICE OF A CLOSED CIRCUIT TELEVISION SYSTEM

When installing a simple CCTV system, we recommend that you follow the four steps below. If the installation has to meet stricter safety requirements, please contact your local Legrand sales office.

The figure opposite shows the relative size of a person (target) on the screen.

Step 1

DEFINITION OF THE NUMBER OF AREAS TO MONITOR

Perform a study with your client using a map of the area to be monitored.

Step 2

SPECIFICATION OF THE EXPECTED RESULTS FOR EACH AREA TO BE MONITORED

The expected results should be agreed with the customer for each area to be monitored. In most cases, this will be one of the following objectives: identification, recognition, detection of intrusions.

For a description of the expected results, please refer to standard EN 50132-7, of which the following is an extract:

The size of an object/target on the monitor screen should have a relation to the operator task, for example: identification (facial identification), recognition (complete identification) or monitoring (overview).

If the target is a person and the CCTV system has an installed limiting resolution of better than 400 TV lines, the recommended minimum sizes of this target are:

a) for identification (facial identification), the target should represent not less than 120% of the image height.
b) for recognition (complete identification), the target should represent not less than 50% of the image height.
c) for monitoring (overview), the target should represent not less than 10% of the image height.

The figure opposite shows the relative size of a person (target) on the screen.

Step 3

SPECIFICATION OF THE NUMBER OF CAMERAS AND THEIR POSITIONS:

The quantity of results expected determines the number of cameras required. For each camera, the most suitable installation position must be identified according to the following parameters: the size of the objects to be observed (expected results), the distance between them and the installation requirements for the camera (internal/external, wall/ceiling/flush-mounting, etc.).

CAUTION

Ensure that the cameras are used in accordance with the laws and regulations in force, both in terms of privacy and staff safety. The images, sounds, voices and names recorded are personal – and sometimes sensitive – data – which may also be protected by copyright or third party intellectual property rights.

Therefore, any person using the equipment must comply with the following:

– strict compliance with legislation regarding the protection of personal data;
– respect for data security obligations;
– respect for image and representation rights, as well as all requirements in terms of copyright and intellectual and industrial property rights. Legrand cannot be held responsible for any illegal use of its products by its customers.

Step 4

SELECTION OF THE MOST APPROPRIATE EQUIPMENT TO ACHIEVE THE DESIRED RESULTS:

It is now possible to identify the necessary products for installation of the system: cameras, video recorders, screens, accessories.

CAMERAS:

Once all the information from the previous step has been gathered, it is possible to identify the most suitable compact cameras, using the simple user tables provided for this family of products. If compact cameras cannot be used due to the requirements of certain applications, high performance modular cameras are also available. For each one, it is possible to select the most suitable accessories (e.g. supports, housings, IR illuminators, lenses).

DIGITAL VIDEO RECORDERS:

To be selected based on the number of cameras to be connected and the secondary functions provided.

SCREENS:

To be selected based on display dimensions and available space.

THE CAMERAS KEY PRODUCTS IN A CLOSED CIRCUIT TELEVISION SYSTEM

As the cameras do not all offer the same “visualisation” function, it is important to carefully select an appropriate camera, taking into account the following points:

THE INSTALLATION ENVIRONMENT

Waterproof products (IP 55 or IP 66) can be installed outdoors. If there is a risk of defacement, products must be vandal resistant (IK 10). Compact and modular cameras remain visible, while dome cameras, mini-cameras and hidden cameras facilitate covert surveillance.

THE SCENE TO BE FILMED

How far is the scene to be filmed from the location where the camera is to be installed? What are the dimensions of the scene to be filmed? Are the dimensions fixed and precise (door or entrance)?
-> Fixed or adjustable focal length.
Are the dimensions variable (wide angle and zoom)?
-> Camera with zoom or high resolution camera (megapixels).
Is the scene wider than the camera’s field of view?
-> Motorized dome camera

INSTALLATION RECOMMENDATIONS

Install the cameras at a height of 3 to 4 meters. The camera stand (housing, support, etc.) should enable it to be electrically insulated from the ground (to avoid ground loops). The camera must be connected to the power supply with strict regard for phase and neutral, as cameras connected to alternating current (230 V) use the network’s 50 Hz frequency for synchronization: if all the cameras are connected correctly, they will also be synchronized.

Performance of the lighting systems strongly depends on the type of surfaces illuminated (reflectance) and the spectrum of light generated. When choosing the type of camera, you should take into account the fact that color cameras require 10 times more light than black and white cameras. The amount of light on the scene to be observed should in practice be 10 times the minimum quantity of light required by the camera. The reference parameter to consider in order to choose the correct camera based on the available light is the “sensitivity” of the camera. The following table gives the brightness values for certain specific conditions.

RECORDERS KEY PRODUCTS IN A CLOSED CIRCUIT TELEVISION SYSTEM

Insofar as it is impossible to constantly monitor all installations, scenes should be recorded for later review. Digital video recorders complete a CCTV installation and must be chosen according to the following criteria:

NUMBER OF CAMERAS

The type and number of recorders are determined by the number of cameras for which images must be recorded. However, in cases where the number of installed cameras is expected to increase, we recommend that this upscaling be taken into account by choosing a recorder with a larger number of inputs. When the total number of cameras is greater than or equal to the capacity of a 16-input recorder (analog or IP), it is still possible to use one (or more) central management point(s) as long as the recorders are connected to the same network (local or remote).

TYPE OF RECORDING

Whether you want continuous or event-related recording, the duration of data retention and image quality determine the size of the storage medium (hard disk). Some recorders also offer the ability to add hard disks, while others do not.

POSITIONING

The installation location of the recorder is an important factor to bear in mind: need to access the controls on the front (or vice versa), installation in a computer cabinet or housing, direct installation into a rack.

SCREENS KEY PRODUCTS IN A CLOSED CIRCUIT TELEVISION SYSTEM

Analysis or verification of a scene may be performed:

LIVE

The image from the camera is transmitted to a screen or to another remote video support.

RECORDED

The image is stored by the recorder for viewing on demand. However, it is possible to combine the two modes of use, i.e. a recorded scene can be displayed directly on the screen.

LOCAL

The screen is connected directly to the camera or the recorder.

REMOTE

Internet-based visualization via a PC or a smartphone.

SINGLE CHANNEL OR MULTICHANNEL MODE

The recorders allow simultaneous viewing of multiple video channels on one screen (windowing).

TRANSMISSION AND CONNECTION KEY PRODUCTS IN A CLOSED CIRCUIT TELEVISION SYSTEM

This function ensures the link between the above functions. You should select whether the installation will be analog or IP:

AN ANALOG VIDEO SIGNAL CAN BE TRANSMITTED:

Via coaxial cable:

this is an easy to implement solution requiring no additional programming or products. The length of each connection is limited to 300 m.

Via twisted pair (FTP):

this can be integrated into the structure’s wiring and enables you to switch to an all-IP solution. Transmitters and receivers (baluns) must then be installed at each end of the connection. By using amplified transmitters and receivers, the length of the connection can be increased to 1200 m. The power supply to these units is typically 12 V and can be provided:

– Via an independent power supply for each camera, located close-by.

– Via a centralized power supply for multiple cameras. Connection to the above system can be achieved using composite cables integrating the coaxial cable and two power cables. Choosing twisted pair (PoA) for powering analog cameras enables migration to an IP or PoE solution when connecting to the same network (local or remote).

AN IP VIDEO SIGNAL MUST BE TRANSMITTED:

Via twisted pair (FTP):

enabling the installation of several other cameras if the IP installation has been correctly dimensioned. The power supply to these units is typically 12 V and can be provided:

– Via an independent power supply for each camera, located close-by.

– Via a centralized power supply for multiple cameras. Connection to the above system can be achieved using composite cables integrating the coaxial cable and two power cables.

– Via the network, if it is PoE (Power over Ethernet) compatible.

GLOSSARY

Advanced automatic path:

Similar to the single automatic path function, except that the movement follows a path which can be programmed in any direction.
For example, it can be programmed by saving a manual path from the control station.

Compact or all-in-one:

Camera supplied with lens and mechanism already affixed. The form of the mechanism allows for wall-mounting and it is usually equipped with protection to prevent rain water from entering.

Dome:

Camera supplied with lens and mechanism already affixed. The format of the mechanism allows mounting on the ceiling or a suspension arm. The translucent dome masks the camera angle.

Fixed Focus:

Lens with fixed focal length and camera angle.

Focal length:

This value, measured in millimeters, is directly related to the angle of observation. A short focal length offers a wide-viewing angle, while a long focal length offers a telephoto effect with a smaller viewing angle.

Image quality:

An image is defined by its resolution. There are 6 formats (the values in brackets are in pixels):

QCIF (176 x 144)
CIF (352 x 288)
2CIF (704 x 288)
4CIF (704 x 576)
HalfD1/HD1 (360 x 576)
D1/fullD1 (720 x 576)
HD 720 (1 280 x 720)
HD 1 080 (1 920 x 1 080)
WD1/960H (960 x 576)
QCIF
CIF
4CIF
HD 720
HD 1080

Mini-camera :

The camera is supplied complete with lens and can easily be concealed because of its small size.

Modular camera:

Camera supplied without lens, so an appropriate lens can be affixed.

Motorised camera:

Camera capable of extremely fast movement. It can change position very quickly and follow the movements of any object/target.

PoA (Power over Analog):

Supplies power to an analog camera via a twisted pair cable. Requires the installation of balloons at the camera.

PoE (Power over Ethernet):

Supplies power to an IP camera via the network cable. Requires the installation of a PoE injector as power supply.

Recording quality:

The recording quality depends on the resolution of the recorded image and the number of images in one second of recording.

Resolution :

The resolution indicates the quality of the image reproduced. The quality of the image captured by a camera is defined by the number of vertical lines. The current industry standard regarding the resolution of CCTV cameras is 330 lines for color cameras and 380 lines for black and white cameras. The number of lines that a camera must produce to be termed a “high resolution” camera is not defined by any
standard. According to current manufacturing standards, a “high resolution” color camera generally provides more than 420 lines, while a “high resolution” black and white camera provides more than 480 lines.

Sensitivity:

This refers to the camera’s ability to reproduce a video signal with a particular brightness value, which is the minimum amount of light (measured in lux) necessary to obtain a video signal. The higher the sensitivity of the camera, the lower the quantity of light required to obtain a video signal. A high-sensitivity camera will also require less light to obtain a good video image. Be careful not to confuse the minimum required quantity of light (sensitivity) with the ambient lighting. Although these two values a re both measured in lux, the amount of light detected by the camera is that reflected by objects and not that coming from the ambient lighting.

Simple automatic path:

the motorized camera moves automatically along a programmable path that is repeated cyclically. The movement follows linear paths between predetermined intermediate points.

Types of screen connection:

The maximum resolution depends on the connection type.

Coaxial: 720 x 576,

VGA: 1024 x 768,

HDMI: 1920 x 1080

Varifocal:

Lens which enables manual adjustment of the focal length. These lenses are designed to be light and compact and can be used in numerous situations. For example, if a 6 mm fixed lens is required, a 3.5-8 mm varifocal lens, adjusted to be fixed at 6 mm, could be used.

Zoom:

Lens which enables the physical characteristics of its focal length to be modified in order to cover a great distance. These lenses are classified according to their magnification (x6, x10, etc.). Manual and motorized versions are available on the market.

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