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Video Management System
A video management system, also known as video management software plus a video management server, is a component of a security camera system that in general: * Collects video from cameras and other sources * Records / stores that video to a storage device * Provides an interface to both view the live video, and access recorded video A VMS can be the software component of a network video recorder (NVR) and digital video recorder (DVR), though in general a VMS tends to be more sophisticated and provide more options and capabilities than a packaged NVR device. Due to improvements in technology, it is necessary to make a distinction between a VMS and the built-in features of modern network based security cameras. Many modern network cameras offer internal capabilities to record and review video directly themselves via a web browser and without the use of a VMS. However a camera's built-in web interface is typically exclusive to the camera itself and does not normally provide a shar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Security Camera
A closed-circuit television camera can produce images or recordings for surveillance or other private purposes. Cameras can be either video cameras, or digital stills cameras. Walter Bruch was the inventor of the CCTV camera. The main purpose of a CCTV camera is to capture light and convert it into a video signal. Underpinning a CCTV camera is a CCD sensor (charge-coupled device). The CCD converts light into an electrical signal and then signal processing converts this electrical signal into a video signal that can be recorded or displayed on the screen. Video cameras Video cameras are either analogue or digital, which means that they work on the basis of sending analogue or digital signals to a storage device such as a video tape recorder or desktop computer or laptop computer. Analogue These cameras can record straight to a video tape recorder which can record analogue signals as pictures. If the analogue signals are recorded to tape, then the tape must run at a very sl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Video Recorder
A network video recorder (NVR) is a specialized computer system that includes a software program that records video in a digital format to a disk drive, USB flash drive, SD memory card or other mass storage device. An NVR contains no dedicated video capture hardware. However, the software is typically run on a dedicated device, usually with an embedded operating system. Alternatively, to help support increased functionality and serviceability, standard operating systems are used with standard processors and video management software. An NVR is typically deployed in an IP video surveillance system. Network video recorders are distinct from digital video recorders (DVR) as their input is from a network rather than a direct connection to a video capture card or tuner. Video on a DVR is encoded and processed at the DVR, while video on an NVR is encoded and processed at the camera, then streamed to the NVR for storage or remote viewing. Additional processing may be done at t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Video Recorder
A digital video recorder (DVR) is an electronic device that records video in a digital format to a disk drive, USB flash drive, SD memory card, SSD or other local or networked mass storage device. The term includes set-top boxes with direct to disk recording, portable media players and TV gateways with recording capability, and digital camcorders. Personal computers are often connected to video capture devices and used as DVRs; in such cases the application software used to record video is an integral part of the DVR. Many DVRs are classified as consumer electronic devices; such devices may alternatively be referred to as personal video recorders (PVRs), particularly in Canada. Similar small devices with built-in (~5 inch diagonal) displays and SSD support may be used for professional film or video production, as these recorders often do not have the limitations that built-in recorders in cameras have, offering wider codec support, the removal of recording time limitations and hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ONVIF
ONVIF (the Open Network Video Interface Forum) is a global and open industry forum with the goal of facilitating the development and use of a global open standard for the interface of physical IP-based security products. ONVIF creates a standard for how IP products within video surveillance and other physical security areas can communicate with each other. ONVIF is an organization started in 2008 by Axis Communications, Bosch Security Systems and Sony. It was officially incorporated as a non-profit, 501(c)6 Delaware corporation on November 25, 2008. ONVIF membership is open to manufacturers, software developers, consultants, system integrators, end users and other interest groups that wish to participate in the activities of ONVIF. The ONVIF specification aims to achieve interoperability between network video products regardless of manufacturer. ONVIF concerns itself with standardization of communication between IP-based physical security products to achieve open interoperabil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RS-422
RS-422, also known as TIA/EIA-422, is a technical standard originated by the Electronic Industries Alliance that specifies electrical characteristics of a digital signaling circuit. It was meant to be the foundation of a suite of standards that would replace the older RS-232C standard with standards that offered much higher speed, better immunity from noise, and longer cable lengths. RS-422 systems can transmit data at rates as high as 10 Mbit/s, or may be sent on cables as long as at lower rates. It is closely related to RS-423, which uses the same signaling systems but on a different wiring arrangement. RS-422 specifies differential signaling, with every data line paired with a dedicated return line. It is the voltage difference between these two lines that define the mark and space, rather than, as in RS-232, the difference in voltage between a data line and a local ground. As the ground voltage can differ at either end of the cable, this required RS-232 to use signals with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RS-485
RS-485, also known as TIA-485(-A) or EIA-485, is a standard defining the electrical characteristics of drivers and receivers for use in serial communications systems. Electrical signaling is balanced, and multipoint systems are supported. The standard is jointly published by the Telecommunications Industry Association and Electronic Industries Alliance (TIA/EIA). Digital communications networks implementing the standard can be used effectively over long distances and in electrically noisy environments. Multiple receivers may be connected to such a network in a linear, multidrop bus. These characteristics make RS-485 useful in industrial control systems and similar applications. Overview RS-485 supports inexpensive local networks and multidrop communications links, using the same differential signaling over twisted pair as RS-422. It is generally accepted that RS-485 can be used with data rates up to 10 Mbit/s or, at lower speeds, distances up to . As a rule of thumb, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pan–tilt–zoom Camera
PTZ is an abbreviation that stands for pan-tilt-zoom. The term " pan" refers to the horizontal movement of the lens, "tilt" refers to the vertical movement of the lens, and "zoom" refers to the adjustment of the focal length of the lens. PTZ cameras are robotic devices that are made up of mechanical pieces that enable them to pan from left to right, tilt up and down, and zoom in and out of the picture. PTZ cameras may also zoom in and out of the image. They are often positioned at guard posts where active employees may manage them using a remote camera controller. Their primary function is to monitor expansive open regions that need views in the range of 180 or 360 degrees. Depending on the camera or software being used, they may also be set up to automatically monitor motion-activated activities or adhere to a defined schedule. How do PTZ Cameras Work? A pan-tilt-zoom camera may be operated by remote control, by computer software, or it may be physically present for the purpos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Character Recognition
Optical character recognition or optical character reader (OCR) is the electronic or mechanical conversion of images of typed, handwritten or printed text into machine-encoded text, whether from a scanned document, a photo of a document, a scene-photo (for example the text on signs and billboards in a landscape photo) or from subtitle text superimposed on an image (for example: from a television broadcast). Widely used as a form of data entry from printed paper data records – whether passport documents, invoices, bank statements, computerized receipts, business cards, mail, printouts of static-data, or any suitable documentation – it is a common method of digitizing printed texts so that they can be electronically edited, searched, stored more compactly, displayed on-line, and used in machine processes such as cognitive computing, machine translation, (extracted) text-to-speech, key data and text mining. OCR is a field of research in pattern recognition, artificial intellig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fisheye Camera
A fisheye lens is an ultra wide-angle lens that produces strong visual distortion intended to create a wide panoramic or hemispherical image. Fisheye lenses achieve extremely wide angles of view, well beyond any rectilinear lens. Instead of producing images with straight lines of perspective ( rectilinear images), fisheye lenses use a special mapping ("distortion"; for example: equisolid angle, see below), which gives images a characteristic convex non-rectilinear appearance. The term ''fisheye'' was coined in 1906 by American physicist and inventor Robert W. Wood based on how a fish would see an ultrawide hemispherical view from beneath the water (a phenomenon known as Snell's window). Their first practical use was in the 1920s for use in meteorology to study cloud formation giving them the name "whole-sky lenses". The angle of view of a fisheye lens is usually between 100 and 180 degrees, although lenses covering up to 280 degrees exist (see below). Their focal lengths dep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
