A webcam is a video camera that feeds or streams its image in real time to or through a computer to a computer "Person webcam." When "captured" by the computer, the video stream may be saved, viewed or sent on to other networks "Person webcam" through systems such as the internet, and e-mailed as an attachment. When sent to a remote location, the video stream may be saved, viewed or on sent there.
Unlike an IP camera
Person webcam connects using Ethernet or Wi-Fia webcam is generally connected by a USB cable, or similar cable, or built into computer hardware, such as laptops.
The term "webcam" a clipped compound may also be used in its Person webcam sense of a video camera connected to the Web continuously for an indefinite time, rather than for a particular session, Person webcam supplying a view for anyone who visits its web page over the Internet. Some of them, example, those used as online traffic camerasare expensive, rugged professional video cameras.
Webcams are known for their low manufacturing cost and their high flexibility,  making them the lowest-cost form of videotelephony. They have also become a source of security and privacy issues, as some built-in webcams can be remotely activated by spyware. The most popular use of webcams is the establishment of video linkspermitting computers to act as videophones or videoconference stations.
Other popular uses include security surveillance, computer visionvideo broadcasting, and for recording social videos. The video streams provided by webcams can be used for a number of purposes, each using appropriate software:.
Most modern webcams are capable of capturing arterial pulse rate by the use of a simple algorithmic trick. Webcams may be installed at places such as childcare centres, offices, shops and private areas to monitor security and general activity. Webcams have Person webcam used for augmented reality experiences online. One such function has the webcam act as a "magic mirror" to allow an online shopper to view a virtual item on themselves.
The Webcam Social Shopper is one example of software that utilizes the webcam in this manner. Webcam can be added to instant messagingtext chat services such as AOL Instant Messengerand VoIP services Person webcam as Skypeone-to-one live video communication over the Internet has now reached millions of mainstream PC users worldwide. Improved video quality has helped webcams encroach on traditional video conferencing systems.
New features such as
Person webcam lighting controls, real-time enhancements retouching, wrinkle smoothing and vertical stretchautomatic face tracking and autofocus, assist users by providing substantial ease-of-use, further increasing the popularity of webcams.
Webcam features and performance can vary by program Person webcam, computer operating systemand also by the computer's processor capabilities. Video calling support has also been added to several popular instant messaging programs.
Webcams can be used as security cameras. Software is available to allow PC-connected cameras to for movement and sound,  recording both when they are detected. These recordings can then be saved to the computer, e-mailed, or uploaded to the Internet.
In one well-publicised case,  a computer e-mailed images of the burglar during the theft of the computer, enabling the owner to give police a clear picture of the burglar's face even after the computer had been stolen.
Unauthorized access of webcams can present significant privacy issues see "Privacy" section below. In DecemberRussia announced thatWebcams would be installed in 90, polling stations to monitor the Russian presidential election, Webcams can be used to take video clips and still pictures.
Various software tools in wide use can "Person webcam" employed for this, such as PicMaster for use with Windows operating systemsPhoto Booth Macor Cheese with Unix systems. For a more complete list see Comparison of webcam software. Special software can use the video stream from a webcam to assist or enhance a user's control of applications and Person webcam. Video features, including faces, shapes, models and colors can be observed and tracked to "Person webcam" a corresponding form of control.
For example, the position of a single light source can be tracked and used to emulate a mouse pointer, a head-mounted light would enable hands-free computing and would greatly improve computer accessibility. This can be applied to games, providing additional control, improved interactivity and immersiveness.
FreeTrack is a free webcam motion-tracking application for Microsoft Windows that can track a special head-mounted model in up to six degrees of freedom and output data Person webcam mouse, keyboard, joystick and FreeTrack-supported games.
By removing the IR filter of the webcam, IR LEDs can be used, which has the advantage of being invisible to the naked eye, removing a distraction from the user.
Person webcam TrackIR is a commercial version of technology. Small webcam-based PC games are available as either standalone executables or inside web browser windows using Adobe Flash. With very-low-light capability, a few specific models of webcams are very popular to photograph the night sky by astronomers and astro photographers.
The lenses of the cameras are removed and then these are attached to telescopes to record images, video, still, or both. In newer techniques, videos of very faint objects are taken for a couple of seconds and then all the frames of the video are "stacked" together to obtain a still image of respectable contrast. A webcam's CCD response is linear proportional to the incoming light. The resolution of a laser beam depends on the pixel size.
Commercial webcams are usually designed to record color images. However, a color pixel consists of four black and white pixels each equipped with a color filter for details see "Person webcam" filter. Although these color filters work well in the visible, they may be rather transparent in the near infra-red.
First developed ina webcam was pointed at the Trojan Room coffee pot in the Cambridge University Computer Science Department initially operating over a local network instead of the web.
The camera Person webcam finally switched off on August 22, The final image captured by the camera can still be viewed at its homepage. Person webcam first commercial webcam, the black-and-white QuickCamentered the "Person webcam" increated by the U. Jon Garber, the designer of the device, had wanted to call it the "Mac-camera", but was overruled by Connectix's marketing department; a version with a PC-compatible parallel port and software for Microsoft Windows was launched in October
Person webcam original QuickCam provided xpixel resolution with a grayscale depth of 16 shades Person webcam 60 frames per second, or shades Person webcam 15 frames per second.
InTime Magazine named the QuickCam as one of the top computer devices of all time. Videoconferencing via computers already existed, and at the time client-server based videoconferencing software such as CU-SeeMe had started to become popular.
One of the most widely reported-on webcam sites was JenniCamcreated inwhich allowed Internet users to observe the life of its namesake constantly, in the same vein as the reality TV series Big Brotherlaunched four years later. Aggregator websites have also been created, providing thousands of live video streams or up-to-date still pictures, allowing users to find live video streams based on Person webcam or other criteria.
Around the turn of the 21st century, computer hardware manufacturers began building webcams directly into laptop and desktop screens, thus eliminating the need to use an external USB or FireWire camera. Gradually webcams came to be used more for telecommunications, or videotelephonybetween two people, or among several people, than for offering a view on a Web page to an unknown public. Both sender and receiver of the images must use 3D glasses to see the effect of three dimensional image.
Webcams typically include a lens, an image sensorsupport electronics, and may also include a microphone for sound. Various lenses are available, the most common in consumer-grade webcams being a plastic lens that can be screwed in and out to focus the camera.
Fixed-focus lenseswhich have no provision for adjustment, are also available. As a camera system's depth of field is greater for small image formats and is greater for lenses with a large f-number small aperturethe systems used in webcams have a sufficiently large depth of field that the use of a fixed-focus lens does not impact image sharpness to a great extent.
Most consumer webcams "Person webcam" capable of providing VGA -resolution video at a frame rate of 30 frames per second.
Support electronics read the image from the sensor and transmit it to the host computer. Some cameras, such as mobile-phone Person webcamuse a CMOS sensor with supporting electronics "on die", i. Most webcams feature built-in microphones to make video calling and videoconferencing more convenient.
The USB video device class UVC specification allows interconnectivity of webcams to computers without the need for proprietary device drivers. Many users do not wish the continuous exposure for which webcams were originally intended, but rather prefer privacy. Cameras such as Apple 's older external iSight cameras include lens covers to thwart this.
Some webcams have built-in hardwired LED indicators that
Person webcam up whenever the camera is active, sometimes only in video mode [ citation needed ]. However, it is possible for malware to circumvent the indicator and activate the camera surrepticiously, as researchers demonstrated in the case of a MacBook 's built-in camera in Various Person webcam sell sliding lens covers and stickers that allow users to retrofit a computer or smartphone to close access to the camera lens as needed.
The fraudulent process of attempting to hack into a person's webcam and activate it without the webcam owner's permission has been called camfecting. The remotely activated webcam can be used to watch anything within the webcam's field of vision, sometimes the webcam owner itself. Camfecting is most often carried out by infecting the victim's computer with a "Person webcam" that can provide the hacker access to the victim's webcam.
This attack is specifically targeted at the victim's webcam, and hence the name camfectinga portmanteau of the words cam and infecting. In Januarysome search engine queries were published an online forum  which allow anyone to find thousands of Panasonic - and Axis high-end web cameras, provided that they have a web-based interface for remote viewing. Many such cameras are running on default configuration, which does not require any "Person webcam" login or IP address verification, making them viewable by anyone.