2. What are the major advanced features offered by the DVD-Video format ?

Over two continuous hours of high-quality digital video and audio on a typical 8.5-Gbyte single-sided, dual-layer disc.

Support for movies in both standard and widescreen display (in 4:3 and 16:9 aspect ratios). Widescreen movies can be displayed in the letterbox format on a standard TV set.

Each video title set can have up to 8 tracks of digital audio (for multiple audio languages, commentaries, documentary versions, etc.). Each audio track can be configured differently depending upon the audio format (2-channel ac3 stereo, 5.1-channel Digital Dolby, etc).

Support up to 32 subpicture streams for multiple language subtitles and karaoke tracks. Since the subtitles are essentially bitmaps overlaid on the video stream, non-Latin characters such as Chinese scripts can be displayed without problems.

Up to 9 camera angles (different viewpoints can be selected by the viewer during playback or automatically selected based upon criteria such as the default language settings, parental management level, etc.). Camera angles are often used to turn on and off analog karaoke subtitles already incorporated as part of the original video. The use of camera angles greatly enhances video materials that simulate virtual reality. The adult entertainment industry makes heavy use of this DVD feature.

Seamless branching of video (for multiple story lines or different viewer ratings such as G, PG, R-rated on a single disc).

On-screen menus for ease of title and chapter selection.

Simple point-and-click interactive features for games, quizzes, audio setup, and user language preferences.

Direct access to any part of the disc due to the physical characteristics of the DVD media. Most DVD players supports rewind and fast forward at various speeds: 1X, 2X, 4X, and up to 32X. 32X means 32 times faster than the normal playback speed at 1X. Additional viewing enhancements such as digital zoom, perfect freeze-frame and slow motion viewing are not uncommon.

Ability to search by title, chapter, track, and timecode and programmability (playback of a selected chapter, a selected sequence of chapters, random and repeat play).

Durable (no wear and tear from playing since there is nothing touching the disc).

Magnetic fields do not have any effect on the DVD media.

Compact size (easy to handle, store, and ship; players can be portable; the replication cost is much cheaper than tapes or laserdiscs). There are two sizes: the 12-cm standard size and 8-cm mini disc size. The smaller disc size has approximately 25% the capacity of the standard size DVD. This smaller size limit does not affect the format specifications of both DVD-Video and DVD-Rom.