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[2.9] Does DVD support HDTV (DTV)? Will HDTV
make DVD obsolete?
Short answers: Partially. No.
First, some quick definitions: HDTV (high-definition
TV) encompasses both analog and digital televisions that have a
widescreen 16:9 aspect ratio and approximately 5 times the resolution
of standard TV (double vertical, double horizontal, wider aspect).
DTV (digital TV) applies to digital broadcasts in general and to
the U.S. ATSC standard in specific. The ATSC standard includes both
standard-definition (SD) and high-definition (HD) digital formats.
The notation H/DTV is often used to specifically refer to high-definition
digital TV.
In December of 1996 the FCC approved the U.S. DTV
standard. HDTVs became available in late 1998, but they are still
expensive and won't become widespread for many years. DVDs are not
HD, but they look great on HDTVs. Over 80 percent of the 2 million
DTV sets sold in the U.S. in 2002 did not have tuners, indicating
that their owners got them for watching DVDs.
DVD-Video does not directly support HDTV. No digital
HDTV standards were finalized when DVD was developed. In order to
be compatible with existing televisions, DVD's MPEG-2 video resolutions
and frame rates are closely tied to NTSC and PAL/SECAM video formats
(see 1.19). DVD does use the same 16:9 aspect ratio of HDTV and
the Dolby Digital audio format of U.S. DTV.
HDTV in the U.S. is part of the ATSC DTV format.
The resolution and frame rates of DTV in the US generally correspond
to the ATSC recommendations for SD (640x480 and 704x480 at 24p,
30p, 60p, 60i) and HD (1280x720 at 24p, 30p, and 60p; 1920x1080
at 24p, 30p and 60i). (24p means 24 progressive frames/sec, 60i
means 60 interlaced fields/sec [30 frames/sec].) The current DVD-Video
spec covers all of SD except 60p. It's expected that future DVD
players will output digital video signals from existing discs in
SDTV formats. The HD formats are 2.7 and 6 times the resolution
of DVD, and the 60p version is twice the frame rate. The ITU-R is
working on BT.709 HDTV standards of 1125/60 (1920x1035/30) (same
as SMPTE 240M, similar to Japan's analog MUSE HDTV) and 1250/50
(1920x1152/25) which may be used in Europe. The latter is 5.3 times
the resolution of DVD's 720x576/25 format. HD maximum data rate
is usually 19.4 Mbps, almost twice the maximum DVD-Video data rate.
In other words, DVD-Video does not currently support HDTV video
content.
HDTV will not make DVD obsolete. Those who postpone
purchasing a DVD player because of HDTV are in for a long wait.
It will take many years before even a small percentage of homes
have HDTV sets. The CEA expects 10 percent of U.S. households to have
HDTV in 2003, 20 percent by 2005, and 30 percent by 2006.
HDTV sets include analog video connectors (composite,
s-video, and component) that work with all DVD players and other
existing video equipment such as VCRs. Existing DVD players and
discs will work perfectly with HDTV sets and provide a much better
picture than any other prerecorded consumer video format, especially
when using a progressive-scan player. Since the cheapest route to
HDTV reception will be HDTV converters for existing TV sets, broadcast
HDTV for many viewers will look no better than DVD.
HDTV displays support digital connections such
as HDMI (DVI) and IEEE 1394/FireWire, although standardization is
not quite finished. Digital connections for audio and video provide
the best possible reproduction of DVDs, especially in widescreen
mode. The DVD Forum finalized specifications for supporting 1394
and HDMI in 2002, and players with DVI/HDMI digital outputs appeared
in 2003. When the DVD stream recording (SR) format is finalized,
DVD-SR players may be usable as "transports" that output any kind
of A/V data (even formats developed after the player was built)
to different sorts of external displays or converters.
The interesting thing many people don't realize
is that DTV happened sooner, faster, and cheaper on PCs. A year
before any consumer DTV sets came out you could buy a DVD PC with
a 34" VGA monitor and get gorgeous progressive-scan movies for under
$3000. The quality of a good DVD PC connected to a data-grade video
projector can beat a $30,000 line-doubler system. (See Digital Connection, and Sleekline for product examples. Video projectors
are available from Barco, Dwin, Electrohome, Faroudja, InFocus, Projectavision, Runco, Sharp, Sony, Vidikron, and others.)
Eventually the DVD-Video format will be upgraded
to an HD-DVD format. See 2.12, 3.13 and 6.5.
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