Webcam
From ECDL.web
Webcams are known for their low manufacturing cost and 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 via spyware.
[edit] History
First developed in 1991, a webcam was pointed at the Trojan Room coffee pot in the Cambridge University Computer Science Department. The camera was finally switched off on August 22, 2001.
The first known commercial webcam, the QuickCam, entered the marketplace in 1994, created by the U.S. computer hardware and software company Connectix, which later sold its product line to another U.S. company, Logitech. The initial QuickCam model was available only for the Apple Macintosh, connecting to it via its serial port, but later became a cross-platform product when QuickCam for Windows was launched in October 1995.
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 telecommunication, or videotelephony, between two people, or among a few people, than for offering a view on a Web page to an unknown public.
The term 'webcam' may also be used in its original sense of a video camera connected to the Web continuously for an indefinite time, rather than for a particular session, generally supplying a view for anyone who visits its web page over the Internet. Some of them, for example those used as online traffic cameras, are expensive, rugged professional video cameras.
[edit] Uses
- Videocalling and conferencing. As webcam capabilities have been added to instant messaging, text chat services such as AOL Instant Messenger, and VoIP services such as Skype, one-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 automatic lighting controls, real-time enhancements (retouching, wrinkle smoothing and vertical stretch), automatic face tracking and autofocus assist users by providing substantial ease-of-use, further increasing the popularity of webcams.
- Video security. Webcams are also used as security cameras. Software is available to allow PC-connected cameras to watch 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 out images as the burglar stole it, allowing the owner to give police a clear picture of the burglar's face even after the computer had been stolen.
- Video clips and stills. Webcams can be used to take video clips and still pictures, various software tools in wide use can be employed for this purpose.
- Input control devices. Special software can use the video stream from a webcam to assist or enhance a user's control of applications and games. Video features, including faces, shapes, models and colors can be observed and tracked to produce 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 allow hands-free computing and would greatly improve computer accessibility. This can also be applied to games, providing additional control, improved interactivity and immersiveness. The Microsoft Kinect for example enables users to control and interact with the Xbox 360 gaming console without the need to touch a game controller, through a natural user interface using gestures and spoken commands.
[edit] Privacy
Many users do not wish the continuous exposure for which webcams were originally intended, but rather prefer privacy. Such privacy is lost when Trojan horse programs allow malicious hackers to activate the webcam without the user's knowledge, providing the hackers with a live video and audio feed. Cameras such as Apple's older external iSight cameras include lens covers to thwart this. Some webcams have built-in hardwired LED indicators that light up whenever the camera is active.
[edit] Effects on modern society
Webcams allow for inexpensive, real-time video chat and webcasting, in both amateur and professional pursuits. They are frequently used in online dating. YouTube is a popular website hosting many videos made using webcams.
Webcams can also encourage telecommuting, where people can work from home utilizing the Internet, rather than having to travel to their office.
Using webcams the deaf, hard-of-hearing and speech-impaired can communicate between themselves and with hearing individuals using sign language.