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Not for a long time. HD-DVD "technology demonstrations" being made by various companies do not mean that HD-DVD is around the corner (the demonstrations mean only that companies are busy jockeying for technology and patent positions in developing the future DVD format). Consider that U.S. HDTV was anticipated to be available in 1989, yet was not finalized until 1996, and did not appear until 1998. And has it made your current TV obsolete yet?
HD-DVD (HD stands for both high-density and high-definition) may be available in 2003 at the very earliest, though 2006 is more likely. It will use blue or violet lasers to read smaller pits, increasing data capacity to around 20 GB per layer. MPEG-2 Progressive Profile--or perhaps another format such as H.263--will probably be used to encode the video. All ATSC and DVB formats will be supported, possibly with the addition of 1080p24. HD-DVD players will play current DVD discs and will make them look even better (with progressive-scan video and picture processing), but new HD-DVD discs won't be playable in older DVD players (unless one side is HD and the other standard DVD).
Ironically, computers will support HDTV before settop players do, since 2x DVD-ROM drives coupled with appropriate playback and display hardware meet the 19 Mbps data rate needed for HDTV. This has led to various "720p DVD" projects, which use the existing DVD format to store video in 1280x720 resolution at 24 progressive frames per second. It's possible that 720p DVDs can be made compatible with existing players (which would only play the 480-line line data).
Note: The term HDVD has already been taken for "high-density volumetric display."
Some have speculated that a "double-headed" player reading both sides of the disc at the same time could double the data rate or provide an enhancement stream for applications such as HDTV. This is currently impossible since the track spirals go in opposite directions (unless all four layers are used). The DVD spec would have to be changed to allow reverse spirals on layer 0. Even then, keeping both sides in sync, especially with MPEG-2's variable bit rate, would require independently tracking heads, precise track and pit spacing, and a larger, more sophisticated track buffer. Another option would be to use two heads to read both layers of one side simultaneously. This is technically feasible but has no advantage over reading one layer twice as fast, which is simpler and cheaper.
See 2.9 for more information about HDTV and DVD.
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Про прогрессив из ФАКа (+) -- Kastor -- 15.03.01@15:13 (Чит.: 115)