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Integrating access control and surveillance system is the solution of combining various hardware and software products into a single platform. It allows users to monitor / control critical situations in a single interface. The integrated solutions provide higher security levels for the organization. Access control restricts and authorizes access of specific locations. surveillance system provides monitoring

System Components
Video surveillance system / CCTV is a system containing the use of cameras, monitor units, and Hard Disk Recorder and multiplexer. Either analog or digital cameras shall be selected in a system based on various designs and applications for the system.

The systems can be installed in both interior and exterior areas of a building and other sectors including Transporation, educational institution, leisure and entertainment area, commercial mall, etc. The Video Surveillance System can always operate continuously, can be designed to record in response to movement, or set to record in specific duration or period of time in day.

The cameras may be obvious and placed outdoors to prevent crime and identify criminals after crimes, or the camera can be hidden more to record evidence with fewer chances of being destroyed. However, it is crucial to note that the laws regulate the location of security cameras for reasons, and the statutory requirements may vary in different places or countries.

Footage can be live monitored by security / police in a central security center. The users can monitor remotely if an IP camera is included in the system and provided by a monitoring company, the images can be recorded and stored by a Digital Video Recorder (DVR) or Network Video Recorder (NVR) for reviewing the record images after crimes or needs.

Finally, video surveillance systems are closed, which means the video signals are not broadcast. Therefore, others couldn't read and record the content and only authorized users can access the recorded images.

Types of Cameras
There are a variety of cameras that can be selected in video surveillance systems. All the camera options will either be the analog or digital / internet protocol (IP) category:


 * Analog: traditional cameras usually provide lower resolution images and required connection by coaxial cable for each camera to the DVR and separate power from wires connection is needed. Moreover, the cameras' location must be near the DVR for better quality footage, so that the range of vision for analog camera is smaller than the digital / IP camera and more cameras are required by applying analog camera in the same area of space. However, the cost of an analog camera is cheaper, and it can provide reasonable prices for the end user, and network's bandwidth would not be occupied by these camera design.
 * Digital / IP: digital cameras are commonly used Internet Protocol Camera which provide much higher resolution images than traditional analog cameras. The IP camera connects to NVR with only one cable through the power over ethernet (PoE) switch, extra power source is not required. The images transmitted through the cable would not be degraded during the digital enlarge and maintain its quality. The drawback of IP cameras is that more bandwidth from network and storage for recorded images are required, the cost of IP camera is more expensive than the traditional analog one. Some of the IP cameras provide the convenience of being able to connect to Wi-Fi networks, which means it can be remotely accessed and more hackable. As a result, security issue shall be another concern and required to pay more for the security features.

For both analog and digital cameras used nowadays, more and more additional features are added such as multiple direction cameras, camera can capture quality images in limited light environment, camera with long-distance capturing functionality, etc.

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The specialized camera existing in the market nowadays:


 * Internal / External Dome Cameras: Most used for indoor / outdoor surveillance due to the ability to blend in with the surroundings. Dome cameras can be mounted to a wall and usually mounted on the ceiling.
 * PTZ (Pan/Tilt/Zoom) Cameras: these cameras allow active monitoring and live surveillance, the security guard can pan and tilt the PTZ camera by its camera mount or zoom the lens farther or closer.
 * Bullet Cameras: the enclosed casing is long and cylindrical and usually weather resisting housing, which can be placed in an outdoor area. These cameras also provide long-distance views.
 * Thermal Image / Infrared Cameras: apply in airports, seaports, and other premises that contain critical infrastructure. These cameras can provide 24/7 surveillance monitoring and they can capture objects moving in darkness areas.
 * High Definition Cameras: providing high resolution record images that are used in high-risk locations such as casinos and banks.

Video Surveillance System Monitoring
There are several ways to monitor the footage produced by a video surveillance system. The most traditional method of surveillance monitoring is by security guard in security control center who is viewing the live footage on the multiple images in monitors / displays units. For analog systems, the cameras, DVRs and display units are connected by the coaxial cable, there are only monochrome screens for the monitor.

Nowadays, the majority of security cameras being digital / IP cameras, the images transmitted by the owner's network. Although the recorded images can still be monitored in the security center by the security guard, the recording can also be accessed via computers and mobile devices anywhere. Moreover, some of the cameras are able to wait until detecting movement and sending SMS messages to authorized personnel to check the live footage.

Recording Video in Surveillance Systems
Firstly, a CCTV camera captures the movement and begins the recording of the footage, the recorded images can be reviewed when necessary. If the images being recorded for every second, the amount of the storage would be a concern for the system owner.

For applying analog cameras in the system, the footage will be transmitted though the coaxial cable to the DVRs and record the video images from analog camera into digital format. Once the hard disk of the DVR is full, older images will be replaced by newer ones and starting with the oldest images.

For system using digital / IP cameras, DVR will be replaced by NVR. The IP cameras will be connected to the NVR by network cable or network switch. The recorded images will be encrypted and stored in a hard drive and can be reviewed by the authorized personnel through the connected monitor display units in the security control center or even the web browser or mobile app in any location.

New Technologies applied in Video Surveillance Systems
Modern Tecnologies have combined with video surveillance systems and greatly enhanced its capability and be more convenience.

The video surveillance cameras are now able to offer facial recognition, smart cameras such as PTZ cameras with smart tracking that could follow the objects until the object is out of the camera's range. Thermal cameras, night vision, HD full color and others different smart technologies that allow cameras to send immediate signal and interact with the security guard in security center on the specific situation.