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Visual Input - digital and video cameras

This section is concerned with input that is from the real world or is in 3D (three dimensions), where as the scanner section concerns 2D items. The devison is artifical because cartons are dealt with here!

Steven Sasson, an engineer working for Eastman Kodak, is credited with developing the first digital camera, an 8-pound toaster sized box that captured a black-and-white image on a digital cassette tape at a resolution of .01 megapixels in the early 70s. In 1981 Sony marketed the first digital camera in 1981. Digital Cameras have come a long way in the last 10 years. They are now availble for a few pounds, although typically they will cost in the hundreds. They are suppied as part of many mobile phones and a web camera is often part oof a home computer package. Traditional cameras and film processing companies have had to adapt or they are likely to die!

Digital cameras can be classified as follows:

Video cameras

Professional video cameras such as those used in television and production. These typically have multiple image sensors (one per color) to enhance resolution. Professional video cameras usually do not have a built-in VCR or microphone.
Camcorders used by amateurs. These are a combination of camera and VCR to create an all-in-one production unit. They generally include a microphone to record sound, and feature a small LCD to watch the video during filming and playback.
Webcams are digital cameras attached to computers, used for video conferencing or other purposes.
There is a new class of multiple devices used to capure key movents for animation of games, this is however a very specialised use.

Still cameras

Digital still cameras are cameras whose primary purpose is to capture photography in a digital format. Initially, a digital camera was characterized by the use of flash memory and USB or FireWire for storage and transfer of still photographs. However, modern digital photography cameras have a video function, and a growing number of camcorders have a still photography function. In addition, some newer camcorders record video directly to flash memory and transfer over USB and FireWire. Among digital still cameras, most have a rear LCD for reviewing photographs. They are rated in mega pixels; that is, the product of their maximum resolution dimensions. The actual transfers to a host computer are commonly carried out using the USB mass storage device class (so that the camera appear as a drive) or using the Picture Transfer Protocol and its derivatives. All use a CCD (for Charge-Coupled Device) which is a chip comprised of a grid of phototransistors to sense the light intensities across the plane of focus of the camera lens.

Standard Digital Cameras: This encompasses most digital cameras.
Digital SLRs (single lens reflex) typically have a sensor many times larger than that of a standard digital camera, and are targeted at professional photographers and enthusiasts. They are superb for portraiture and artistic photography because they can be customized for various applications with a comprehensive range of exchangeable lenses.

Some key terms:

Connectivity	Many digital cameras can connect directly to a computer to transfer data.USB is the most widely used method, though some have a Firewire port or use Bluetooth Some cameras are able to connect to computer networks wirelessly via Wi-Fi.
Integration	Some devices, likeMobile phone and PDAs contain integrated digital cameras. Mobile phone cameras are even more common than standalone digital cameras.
Storage	Digital cameras need memory to store data. Cheap cameras and cameras secondary to the devices main use (such as a camera phone) use onboard memory, such as flash memory Most dedicated cameras, however, use a removable memory cardto store data.
Autonomous devices	Sone cameras operates without need of a computer . The camera connects to the printer, which then downloads and prints its images. Some DVD recorders and television sets can read memory cards too.