DVD
(digital versatile disc) is an optical disc technology
that is expected to rapidly replace the CD-ROM disc
(as well as the audio compact disc) over the next
few years. The digital versatile disc (DVD) holds
4.7 gigabyte of information on one of its two sides,
or enough for a 133-minute movie. With two layers
on each of its two sides, it will hold up to 17 gigabytes
of video, audio, or other information. (Compare this
to the current CD-ROM disc of the same physical size,
holding 600 megabyte. The DVD can hold more than 28
times as much information!) DVD-Video is the usual
name for the DVD format designed for full-length movies
and is a box that will work with your television set.
DVD-ROM is the name of the player that will (sooner
or later) replace your computer's CD-ROM. It will
play regular CD-ROM discs as well as DVD-ROM discs.
DVD-RAM is the writeable version. DVD-Audio is a player
designed to replace your compact disc player.
DVD
uses the MPEG-2 file and compression standard. MPEG-2
images have four times the resolution of MPEG-1 images
and can be delivered at 60 interlaced fields per second
where two fields constitute one image frame. (MPEG-1
can deliver 30 noninterlaced frames per second.) Audio
quality on DVD is comparable to that of current audio
compact discs. |
