|
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] |
Panning (camera)
In cinematography and photography panning means swivelling a still or video camera horizontally from a fixed position. This motion is similar to the motion of a person when they turn their head on their neck from left to right. In the resulting image, the view seems to "pass by" the spectator as new material appears on one side of the screen and exits from the other, although perspective lines reveal that the entire image is seen from a fixed point of view. The term ''panning'' is derived from '' panorama'', suggesting an expansive view that exceeds the gaze, forcing the viewer to turn their head in order to take everything in. Panning, in other words, is a device for gradually revealing and incorporating off-screen space into the image. Panning should never be confused with tracking or "travelling," in which the camera is not just swivelled but is physically displaced left or right, generally by being rolled parallel to its subject. In video technology, panning refers to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power Over Ethernet
Power over Ethernet, or PoE, describes any of several standards or ad hoc systems that pass electric power along with data on twisted-pair Ethernet cabling. This allows a single cable to provide both data connection and electrical power to devices such as wireless access points (WAPs), Internet Protocol (IP) cameras, and voice over Internet Protocol (VoIP) phones. There are several common techniques for transmitting power over Ethernet cabling. Three of them have been standardized by Institute of Electrical and Electronics Engineers (IEEE) standard IEEE 802.3 since 2003. These standards are known as ''alternative A'', ''alternative B'', and ''4PPoE''. For 10BASE-T and 100BASE-TX, only two of the four signal pairs in typical Cat 5 cable are used. Alternative B separates the data and the power conductors, making troubleshooting easier. It also makes full use of all four twisted pairs in a typical Cat 5 cable. The positive voltage is applied to pins 4 and 5, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Film And Video Terminology
A film also called a movie, motion picture, moving picture, picture, photoplay or (slang) flick is a work of visual art that simulates experiences and otherwise communicates ideas, stories, perceptions, feelings, beauty, or atmosphere through the use of moving images. These images are generally accompanied by sound and, more rarely, other sensory stimulations. The word "cinema", short for cinematography, is often used to refer to filmmaking and the film industry, and to the art form that is the result of it. Recording and transmission of film The moving images of a film are created by photographing actual scenes with a motion-picture camera, by photographing drawings or miniature models using traditional animation techniques, by means of CGI and computer animation, or by a combination of some or all of these techniques, and other visual effects. Before the introduction of digital production, series of still images were recorded on a strip of chemically sensitize ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cameras
A camera is an optical instrument that can capture an image. Most cameras can capture 2D images, with some more advanced models being able to capture 3D images. At a basic level, most cameras consist of sealed boxes (the camera body), with a small hole (the aperture) that allows light to pass through in order to capture an image on a light-sensitive surface (usually a digital sensor or photographic film). Cameras have various mechanisms to control how the light falls onto the light-sensitive surface. Lenses focus the light entering the camera, and the aperture can be narrowed or widened. A shutter mechanism determines the amount of time the photosensitive surface is exposed to the light. The still image camera is the main instrument in the art of photography. Captured images may be reproduced later as part of the process of photography, digital imaging, or photographic printing. Similar artistic fields in the moving-image camera domain are film, videography, and cinematograph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Camera Types
{{Short description, none * Camera, the general term: ** 360 camera (VR camera) ** 3D camcorder ** Action camera ** Animation camera ** Autofocus camera ** Backup camera ** Banquet camera ** Body camera ** Box camera ** Bridge camera ** Camcorder ** Camera phone ** Closed-circuit television camera ** Compact camera ** Compact System cameras ** Dashcam ** Digital camera ** Digital movie camera ** Digital single-lens reflex camera ** Disposable camera ** Document camera ** Event camera ** Field camera ** FireWire camera ** Folding camera ** Front-facing camera ** Gun camera ** Helmet camera ** High-speed camera ** Hidden camera (Spy camera) ** Imago camera ** Instant camera ** IP camera ** Keychain camera ** Large format camera ** Light-field camera ** Live-preview digital camera ** Medium format camera ** Mirrorless interchangeable-lens camera ** Monorail camera ** Movie camera ** Multiplane camera ** Omnidirectional camera ** Onboard camera ** Pinhole camera ** Pinspeck ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eye In The Sky (camera)
The eye in the sky is a term given to casino and other commercial security closed circuit cameras. In casinos, they are positioned to monitor seats, tables, hallways, restaurants, and even elevators closely. The functional component is known as a pan–tilt–zoom camera, or a PTZ, an industry standard term. The PTZ camera is covered by a semi-transparent plastic globe which makes it nearly impossible to see which direction the camera is facing from a distance. Retail stores often install empty globes, giving the appearance of additional cameras. The camera is mounted on a series of interconnected gears and levers, which usually allow two axes of rotation. This rotation can either be controlled manually by an operator using remote-control, or it can be automated using motion sensing technology. In most commercial and civilian applications, both control methods are used simultaneously to allow automated surveillance of general movement while allowing a manual over-ride mode to vi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Automatic Number-plate Recognition
Automatic number-plate recognition (ANPR; see also other names below) is a technology that uses optical character recognition on images to read vehicle registration plates to create vehicle location data. It can use existing closed-circuit television, road-rule enforcement cameras, or cameras specifically designed for the task. ANPR is used by police forces around the world for law enforcement purposes, including to check if a vehicle is registered or licensed. It is also used for electronic toll collection on pay-per-use roads and as a method of cataloguing the movements of traffic, for example by highways agencies. Automatic number-plate recognition can be used to store the images captured by the cameras as well as the text from the license plate, with some configurable to store a photograph of the driver. Systems commonly use infrared lighting to allow the camera to take the picture at any time of day or night. ANPR technology must take into account plate variations from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Closed-circuit Television 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 slo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IP Camera
An Internet Protocol camera, or IP camera, is a type of digital video camera that receives control data and sends image data via an IP network. They are commonly used for surveillance, but, unlike analog closed-circuit television (CCTV) cameras, they require no local recording device, only a local area network. Most IP cameras are webcams, but the term ''IP camera'' or netcam usually applies only to those that can be directly accessed over a network connection. Some IP cameras require support of a central network video recorder (NVR) to handle the recording, video and alarm management. Others are able to operate in a decentralized manner with no NVR needed, as the camera is able to record directly to any local or remote storage media. The first IP Camera was invented by Axis Communications in 1996. History The first centralized IP camera, the ''AXIS Neteye 200'', was released in 1996 by Axis Communications. Although the product was advertised to be accessible from anywhere with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Access
Internet access is the ability of individuals and organizations to connect to the Internet using computer terminals, computers, and other devices; and to access services such as email and the World Wide Web. Internet access is sold by Internet service providers (ISPs) delivering connectivity at a wide range of data transfer rates via various networking technologies. Many organizations, including a growing number of municipal entities, also provide cost-free wireless access and landlines. Availability of Internet access was once limited, but has grown rapidly. In 1995, only percent of the world's population had access, with well over half of those living in the United States, and consumer use was through dial-up. By the first decade of the 21st century, many consumers in developed nations used faster broadband technology, and by 2014, 41 percent of the world's population had access, broadband was almost ubiquitous worldwide, and global average connection speeds exceeded one me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Utilization Categories
In electrical engineering utilization categories are defined by IEC standards and indicate the type of electrical load and duty cycle of the loads to ease selection of contactors and relays. Definition The utilization categories category for low-voltage switchgear defines the characteristic operating conditions for switchgear such as contactors, circuit-breakers, circuit-breaker-fuse units, contactor relays, etc. These devices are dimensioned for different electrical loads and for different operating conditions. The characteristic of the load to be switched or controlled determines the requirements for the switchgear and its correct selection for the intended application. In particular, the stress on the switching path caused by current and voltage during switching on and off is of enormous importance. For example, the switch-on and switch-off current at resistance load corresponds to the continuous operating current, while, for example, squirrel cage motors consumes multiple of 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] |
