Video input is the motion pictures that are entered into the computer.Video devices usually use analog video signals.Computers, however, use digital signals. For video input, a video camera or other video device is connected to a video capture card. The video capture card converts the analog video signals into digital signals that a computer can store and process.
There are two types of video capture cards. these are:
FRAME-GRABBER VIDEO CARDS:These cards capture only a signal frame at a time.
FULL-MOTION VIDEO CARDS:These cards convert analog signals to digital signals at a rate of up to 30 frames per second .This gives the effect of a continuous motion . these cards are also known as video adapters.
New video cameras use digital technology. A digital video(DV) is a video camera that records video as digital signals. A DV camera, therefore, does not need a video card to connect to the computer. It connects directly to a paralled or USB port on the computer.