A GUIDE TO DIGITAL TV 1
A Guide to Digital TV
What is Digital Television?
Digital television (DTV) is a new way of transmitting high quality video and audio to your
TV set. Using DTV, broadcasters can transmit high definition TV (HDTV) images, Dolby digi-
tal surround audio, and new services such as multicasting (transmitting more than one pro-
gram on the same TV channel) and datacasting (providing electronic program guides and
interactive television). Several of these services can be combined into a single digital
broadcast.
Digital Television Services
Digital Picture Quality
DTV programs are transmitted in two different formats. The first is Standard Definition
Television (SDTV) and the second is High Definition Television (HDTV).
SDTV program formats include 480-line interlaced (480i) and 480-line progressive (480p)
video. 480i programs are essentially a digital version of our current analog TV programs,
while the 480p format offers improved image detail over 480i. Some 480p programs are
broadcast in widescreen and are comparable to progressive-scan DVD movies in image
quality.
HDTV program formats include 1080-line interlaced (1080i) and 720-line progressive
(720p). Both HDTV formats are always broadcast in widescreen, and both offer much
higher picture quality than SDTV.
Dolby Surround Sound
With DTV, you can listen to a variety of Dolby digital audio formats from Dolby Surround
2.0 to Dolby Digital 5.1 surround, using your home audio system. Many HDTV programs
are now broadcast with DD 5.1 soundtracks.
Interactive Communications and Datacasting
DTV will allow you to interact with your television; choosing programs from a detailed pro-
gram guide, ordering products on-line while watching TV, and accessing ancillary data
about a program.
MD68-00278A(E)-PREFACE 8/26/02 1:49 PM Page 1