A network camera, also known as Internet camera, IP camera or Internet video camera types , transmits live digital video over an Ethernet network to back-end devices such as a PC or 3G phone. With a dedicated IP address, a built-in web server and audio/video streaming protocols, it can work independently for real-time monitoring Introduction.
mages from network cameras can be viewed with a web browser such as Internet Explore, Firefox, Mozilla and Opera, enabling customers to perform live viewing on different networked devices. In addition, customers can control and manage multiple cameras at the same time in any places where network connection is available. Therefore, an IP surveillance system is easier and more convenient to use compared with a CCTV system
A network camera mainly consists of a lens, an image sensor, an image processor, a video compression SoC (System on Chip) and an Ethernet chip that offers network connectivity for data transmission
When light passes through the lens to the sensor, it is converted to digital signals and then processed by a built-in digital signal processor. The processed video data is then compressed by a multimedia SoC to achieve a smaller data size for optimal transmission. Finally, the video images are sent through the Internet to back-end devices to allow for viewing and storage. Apart from video compression, the SoC is built with a RISC CPU for processing system and network data.
The general interface of a network camera includes a power cord socket, an Ethernet socket, audio I/O ports and digital I/O ports
Camera Types
Generally, network cameras can be divided into four types for different applications, including fixed, pan/tilt/zoom, fixed dome and speed dome.
- Fixed Type
A fixed network camera points in a fixed direction to monitor a specific area, such as hallways, staircases or corridors. Because people can be aware of the camera’s shooting direction, in some cases, it can deter vandalism
and crimes.
- Pan/Tilt/Zoom Type
Capable of changing shooting direction horizontally and vertically to achieve a wide field of view, a pan/tilt network camera is used in many spacious areas, such as lobbies or parking lots.
Some pan/tilt network cameras are integrated with zoom capability so as to provide close-up images of distant objects. Users can easily control PTZ functions through a web browser.
- Fixed Dome Type
A fixed dome network camera, mostly designed for indoor surveillance, has a housing to make the object of interest less aware of where the camera is pointing at. With a 3-axis mechanism, images can remain in an upright
orientation when it is installed either against the wall or on the ceiling. Furthermore, the design of a fixed dome network camera can better fit in with the decor.
- Speed Dome Type
Compared with fixed dome type, a speed dome network camera is integrated with pan, tilt and zoom capabilities, enabling a far greater field of view. With a high zoom capability, image stabilization and 360-degree endless pan, a speed dome camera is mainly used for professional applications, such as airports, banks or city security.