Chapter 1

72 Everything You Ever Wanted to Know About DVD
DVD-Video a Worldwide Standard? Does It Work with NTSC, PAL, and
SECAM?”). DVD does use the same 16:9 aspect ratio of HDTV and the
Dolby Digital audio format of U.S. DTV.
HDTV in the United States is part of the ATSC DTV format. The resolution
and frame rates of DTV generally correspond to the ATSC recommendations
for SD (640�480 and 704�480 at 24p, 30p, 60p, and 60i) and HD
(1280�720 at 24p, 30p, and 60p; 1920�1080 at 24p, 30p, and 60i). (24p
means 24 progressive frames per second [fps], 60i means 60 interlaced
fields per second [30 fps].) 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 International Telecommunication Union—Radio Communication
Sector (ITU-R) is working on BT.709 HDTV standards of 1125/60
(1920�1035/30) (the same as SMPTE 240M, similar to Japan’s analog
MUSE HDTV) and 1250/50 (1920�1152/25 ), which may be used in
Europe. The latter is 5.3 times the resolution of DVD’s 720�576/25 format.
The 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 DVDs obsolete. Those who postpone purchasing a
DVD player because of HDTV are in for a long wait. HDTVs became available
in late 1998 at very high prices (about $5000 and up). 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. Because the cheapest route to HDTV reception will be HDTV converters
for existing TV sets, broadcast HDTV for many viewers will look no
better than DVDs.
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 ith DVI/HDMI digital
outputs appared in 2003. When the DVD stream recording (SR) format
is finalized, DVD-SR players may be usable as “transports” that output any
kind of audio/video data (even formats developed after the player was built)
to different sorts of external displays or converters.