video compression

Video compression refers to reducing the quantity of data used to represent video images, and this is almost always coupled with the goal of retaining as much of the original's quality as possible. Compressed video can effectively reduce the bandwidth required to transmit digital video via terrestrial broadcast, via cable, or via satellite services.
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Compression of sequences of images. Video compression algorithms use the fact that there are usually only small changes from one "frame" to the next so they only need to encode the starting frame and a sequence of differences between frames. This is known as "inter-frame coding" or "3D coding".
MPEG is a committee producing standards in this area and also the name of their standard algorithm. H.261 is another standard.
See also Integrated Information Technology, 3DO, full-motion video, Online Media.