Follow Us:
-
ONVIF, Optical Zoom, OSD
19-04-2017
ONVIF This is a global and open industry forum and standard aimed at facilitating the development and use of an interface of IP-based security products. All ONVIF products are compatible with each other irrespective of the manufacturer’s brand. Optical Zoom This is a true mechanical zoom, which allows a camera to enlarge objects at great distance. It allows one to change the focal length of a camera by adjusting the physical zoom lens. Unlike digital zoom, optical zoom does not suffer from pixilation, but it cannot be performed on video playback via the video recorder’s software. Optical zoom provid
Read More -
MPEG 4
12-04-2017
MPEG stands for Motion Picture Experts Group. This is an ISO group of experts that recommends the manipulation of digital motion images. The most common recommendations are MPEG-1 and MPEG-2. MPEG-4 is a further development of MPEG-2. MPEG-4 is a method of defining compression of audio and visual (AV) digital data. It is designed for transmitting AV data at very low transfer rates over the internet. It is a digital video encoding and compression standard that utilises inter frame encoding to significantly reduce the size of the video stream being transmitted. With inter frame coding, a video sequence is made up of
Read More -
LAN, WAN & RAID
05-04-2017
LAN: LAN, also known as Local Area Network,is a communications network that serves users within a limited geographical area, for example a building or a university campus. It is controlled by a network operating system and uses a transfer protocol. WAN: WAN, Wide Area Network, is a long distance link used to extend and connect remotely-located LANs (local area networks.) RAID: RAID is short for Redundant Array of Independent Disks. It is used to organize two or more hard disks in a manner as though they were one. The data is shared or replicated in such a disk and used to achieve greater capacity, reliability
Read More -
RS232, RS422 and RS485.
29-03-2017
RS232, RS422 and RS485 are the recommended standards for digital communication. They serve as communication interface between computers, CCTV cameras, DVR/NVR, keyboards and other peripherals. They are called as an serial communication interface. RS232 - In telecommunications, RS-232 is a standard for serial communication transmission of data. It formally defines the signals connecting between a DTE (data terminal equipment) such as a computer terminal, and a DCE (data circuit-terminating equipment or data communication equipment), such as a modem.It is a 3 wire unblanced line and used
Read More -
Ethernet
22-03-2017
It is the most commonly used local area network (LAN) access method. Ethernet complies with the IEEE 802.3 standard. The Ethernet standard supports 10 Mbps, 100 Mbps, 1000 Mbps, and 10 Gb (Gigabit) data transmission rates.​ IEEE stands for the Institute of Electrical and Electronics Engineers, the world's leading professional association for the advancement of technology. IEEE 802.1x The IEEE 802.1x standard provides a general method for authentication and authorization in IEEE-802 networks. Authentication is carried out via the authenticator, which checks the transmitted authentication information usi
Read More -
PTZ, Focal length and Field of view
15-03-2017
Pan - The movement of a camera in the horizontal direction or x-axis. Tilt - The movement of a camera in the vertical direction or y-axis. Zoom - Enlarge or reduce the focus by changing of the effective focal length thus allowing many fields of view. It can be an optical zoom where adjustments are made to the lens or it can be a digital zoom whereby we electronically magnify a select portion of the view. ​Focal Length - This is the distance from the optical center of a lens to the image of an object located at an infinite distance from the lens. Long focal lengths give a small field of view and vice
Read More -
IR
08-03-2017
Many specifications in a camera use 'IR' but what is this? IR stands for Infra-red Light. This light is invisible to the eye. It has low frequency and wavelengths longer than 700 nm. It is used in CCTV cameras to record images in the dark. The camera emits this light and records the reflected light determining the distance at which an object is. Normally, a camera operates on normal colour during the day when there is sufficient light, but at night or when there is low light, the IR sensitivity needs to be high.
Read More -
Auto-Iris Lens
22-02-2017
This is a type of lens whose aperture automatically adjusts, i.e opens and closes, in reaction to the lighting. It maintains optimum light to ensure there is proper exposure in the video footage such that the video does not appear washed out or very dark. Security cameras with the auto iris feature are equipped with the ability to compensate for any variations in the light levels, which is particularly useful. This allows for security cameras that are placed outdoors or in an area exposed to high light to adjust accordingly from the aperture in bright sunlight to that in darkness or at night. The circuit of the aut
Read More
