Webcams

Webcams are small cameras, they are used for accessing the images by using the World Wide Web, instant messaging, or a PC video conferencing. Webcams involve a digital camera that uploads images to a web server, either continuously or at regular intervals. It is achieved by a camera attached to a PC, or by dedicated hardware. Video conferencing cameras typically take the form of a small camera connected directly to a PC. Trojan Room coffee pot was the inspiration for the world's first webcam, started in 1991. Recently, Apple and other computer hardware manufactures began building webcams directly into laptop and desktop screens. This eliminates the need to use an external usb or firewire webcam.

Technology used in the Webcam

Webcams typically include a lens, an image sensor, and some requied electronics components. A plastic lens that can be screwed in and out to set the camera's focus. Fixed focus lenses, in which we can not adjust the focus lens, are also available. Image sensors can be CMOS or CCD, the former being dominant for low-cost cameras, but CCD cameras do not necessarily outperform CMOS-based cameras in the low cost price range. Consumer webcams usually offer a resolution in the VGA region, at a rate of around 15 frames per second. For better resolutions and higher frame rates of up to 30 fps, are also available from the brands like Microsoft, Logitech, and Hewlett Packard.

Most webcams feature built in microphones to make video conferencing more convenient. Webcam featuring built in noise cancellation to focus the audio to the speaker who is directly in front of the camera, excluding ambient noise. The USB video device class (UVC) specification allows for interconnectivity of webcams to computers even without proprietary drivers installed.