DVD, which stands for Digital Video Disc, Digital Versatile Disc, or nothing, depending on whom you ask, is the next generation of optical disc storage technology. It's essentially a bigger, faster CD that can hold video as well as audio and computer data. DVD aims to encompass home entertainment, computers, and business information with a single digital format, eventually replacing audio CD, videotape, laserdisc, CD-ROM, and perhaps even video game cartridges. DVD has widespread support from all major electronics companies, all major computer hardware companies, and about half of the major movie and music studios, which is unprecedented and says much for its chances of success (or, pessimistically, the likelihood of it being forced down our throats).
It's important to understand the difference between DVD-Video and DVD-ROM. DVD-Video (often simply called DVD) holds video programs and is played in a DVD player hooked up to a TV. DVD-ROM holds computer data and is read by a DVD-ROM drive hooked up to a computer. The difference is similar to that between Audio CD and CD-ROM. DVD-ROM also includes recordable variations (DVD-R, DVD-RAM, DVD-RW; see 4.3). Most people expect DVD-ROM to be initially much more successful than DVD-Video. Most new computers with DVD-ROM drives can also play DVD-Videos (see 6.1).
There's also a DVD-Audio format. The technical specifications for DVD-Audio have now been finalized. These specs will far surpass anything possible in the CD world.
What are the features of DVD-Video?
Over 2 hours of high-quality digital video (over 8 on a double-sided, dual-layer disc). Support for widescreen movies on standard or widescreen TVs (4:3 and 16:9 aspect ratios). Up to 8 tracks of digital audio (for multiple languages, DVS, etc.), each with as many as 8 channels. Up to 32 subtitle/karaoke tracks. Automatic "seamless" branching of video (for multiple story lines or ratings on one disc). Up to 9 camera angles (different viewpoints can be selected during playback). Menus and simple interactive features (for games, quizzes, etc.). Multilingual identifying text for title name, album name, song name, cast, crew, etc. "Instant" rewind and fast forward, including search to title, chapter, track, and timecode. Durable (no wear from playing, only from physical damage). Not susceptible to magnetic fields. Resistant to heat. Compact size (easy to handle, store, and ship; players can be portable; replication is cheaper).
Noncomedogenic.
Note: Most discs do not contain all features (multiple audio/subtitle tracks, seamless branching, parental control, etc.), as each featuremust be specially authored. Some discs may not allow searching or skipping. Most players support a standard set of features:
Language choice (for automatic selection of video scenes, audio tracks, subtitle tracks, and menus).*
Special effects playback: freeze, step, slow, fast, and scan (no reverse play or reverse step).
Parental lock (for denying playback of discs or scenes with objectionable material).*
Programmability (playback of selected sections in a desired sequence).
Random play and repeat play.
Digital audio output (PCM stereo and Dolby Digital).
Compatibility with audio CDs.
* Must be supported by additional content on the disc.
Some players include additional features:
Component (YUV or RGB) video output for higher-quality picture.
Progressive-scan component (YUV or RGB) output for highest-quality analog picture.
Six-channel analog output from internal audio decoder.
Recognition and output of DTS Digital Surround audio tracks.
Compatibility with Video CDs.
Compatibility with laserdiscs and CDVs.
Ability to play Divx discs.
Reverse single frame stepping.
RF output (for TVs with no direct video input).
Multilingual on-screen display.
Digital zoom (2x or 4x enlargement of a section of the picture). This is a player feature, not a DVD disc
feature.
