Hardware Reference
In-Depth Information
The initial application for DVDs was as an upgrade for CDs as well as a replacement for
prerecorded videotapes. As with CDs, which initially were designed only for music, DVDs have
since developed into a wider range of uses, including video rental, computer data storage, and high-
quality audio.
DVD History
DVD had a somewhat rocky start. During 1995, two competing standards for high-capacity CD drives
were being developed to compete with each other for future market share. One standard, called
Multimedia CD, was introduced and backed by Philips and Sony, whereas a competing standard,
called the Super Density (SD) disc, was introduced and backed by Toshiba, Time Warner, and
several other companies. If both standards had hit the market as is, consumers as well as
entertainment and software producers would have been in a quandary over which one to choose.
Fearing a repeat of the Beta/VHS situation that occurred in the videotape market, several
organizations, including the Hollywood Video Disc Advisory Group and the Computer Industry
Technical Working Group, banded together to form a consortium to develop and control the DVD
standard. The consortium insisted on a single format for the industry and refused to endorse either
competing proposal. With this incentive, both groups worked out an agreement on a single, new, high-
capacity CD-type disc in September 1995. The new standard combined elements of both previously
proposed standards and was called DVD, which originally stood for
digital video disc
but has since
been changed to
digital versatile disc
. The single DVD standard has avoided a confusing replay of
the VHS-versus-Beta-tape fiasco for movie fans and has given the software, hardware, and movie
industries a single, unified standard to support.
After copy protection and other items were agreed on, the DVD-ROM and DVD-Video standards
were officially announced in late 1996. Players, drives, and discs were announced in January 1997 at
the Consumer Electronics Show (CES) in Las Vegas, and the players and discs became available in
March 1997. The initial players were about $1,000 each. Only 36 movies were released in the first
wave, and they were available only in seven cities nationwide (Chicago, Dallas, Los Angeles, New
York, San Francisco, Seattle, and Washington, DC) until August 1997 when the full release began.
After a somewhat rocky start (much had to do with agreements on copy protection to get the movie
companies to go along, and there was a lack of titles available in the beginning), DVD has become an
incredible success. The organization that controls the DVD video standard is called the DVD Forum
and was founded by 10 companies, including Hitachi, Matsushita, Mitsubishi, Victor, Pioneer, Sony,
Toshiba, Philips, Thomson, and Time Warner. Since its founding in April 1997, more than 230
companies have joined the forum. Because it is a public forum, anybody can join and attend the
meetings; the site for the DVD Forum is
www.dvdforum.org
. Because the DVD Forum was unable to
agree on a universal recordable format, its members who are primarily responsible for CD and DVD
technology (Philips, Sony, and others) split off to form the DVD+RW Alliance in June 2000; their site
is
www.dvdservices.org
.
They have since introduced the DVD+RW format, which is the fastest, most
flexible and backward-compatible recordable DVD format. DVD-R/RW and DVD+R/RW are not
just for computer uses either: You can purchase DVD set-top recorders from many vendors (some of
which also contain VCRs to enable you to dub non-copy-protected VCR tapes to DVD).
DVD Construction and Technology
DVD technology is similar to CD technology. Both use the same size discs (120mm diameter, 1.2mm
thick, with a 15mm hole in the center) with pits and lands stamped in a polycarbonate base. Unlike a
