"DVD" is more than a Digital Video Disc

DVD is commonly used as an abbreviation for Digital Video Disc. However, "DVD", which denotes the unified set of standards for next-generation high-density optical discs, is much more than a Digital Video Disc. DVD is for Digital Versatile Disc. It can be used for PC data storage, TV game sets.

People sometimes mistakenly believe that a DVD player is for digital recording and playback of 12-cm optical discs, and that it is to optical discs what the current VHS VCR is to tapes. The DVD-Video player is for read-only discs, i.e. for playback only. In a couple of years' time, a DVD recorder is expected to be marketed.

For recording, DVD-R(write-once) and DVD-RAM(rewritable) discs are planned. Initially, such discs will be for computer applications. It will be a while before a widely affordable DVD recorder becomes available and supersedes home-use VCRs.

DVD-Video achieves superior picture quality comparable to that of professional-use digital video and long recording time thanks to MPEG2 image compression. Without compression, one minute's worth of moving pictures would fill about six hundred 1.44MB floppy disks. 133 minutes' of moving pictures, an amount stor able on one disc with DVD-Video, would fill some 80,000 floppies.

Currently, MPEG2 encoder systems for image compression cost several hundred thousand dollars apiece. Although an MPEG2 decoder chip for playback is already available at a reasonable cost, an MPEG2 encoder suitable for consumer applications is not expected to be realized for some years.

However, it would be possible to achieve DVD recording without a built-in MPEG2 encoder, if DVD-Video system MPEG2 broadcasting were set up. But this isn't likely to happen any time soon, because a great deal of new infrastructure would be required to establish the new broadcasting system.