DVD Demystified

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improve, but many applications of DVD such as video editing, kiosks, and
custom installations are limited by lack of an external control standard. As
with bar codes, some industrial/educational DVD player models include RS-
232 or similar external control ports, but each player manufacturer uses a
different proprietary command protocol.
Poor Computer Compatibility
The multimedia CD-ROM industry has long been plagued by incompatibility
problems. In 1995, return rates of CD-ROMs were as high as 40 percent,
mostly because customers were unable to get them to work on their computers.
Compatibility problems were caused by incorrect hardware or software
setups, defects in video and audio hardware, bugs in video and audio
driver software, and the basic problem that hardware such as CD-ROM
drives and microprocessors often were not powerful enough for the tasks
demanded of them. The potential for problems with DVD-ROM is even
worse. In addition to all the compatibility problems of CD-ROMs, DVD-
ROMs will have to deal with defects in video and audio decoder hardware
or software, incompatibilities of proprietary playback implementations,
decoder software that cannot keep up with full-rate movies, DVD-Video
navigation software that does not correctly emulate a DVD-Video player,
and so on. Not all computers with a DVD-ROM drive will play movies from
a DVD-Video disc, especially computers that are upgraded from a CD-ROM
to a DVD-ROM drive. Someone buying or upgrading a computer may not
understand this.
No WebDVD Standard
Chapter 7
One of the most interesting uses of DVD is in combination with HTML and
the Internet. Hollywood studios, corporations, educators, and thousands of
other DVD makers are excited about the potential of combining the best of
DVD with the best of the Internet. Unfortunately, the DVD-Video specification
has no provisions to make this easier or standardized. The DVD-Audio
specification does have a URL link feature, but it hardly scratches the surface.
Other groups are working on standards for Web-connected DVDs, but
most enhanced discs only work on certain platforms. See Chapter 11 for
more on WebDVD.