DVD Demystified

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screens one at a time. Finally, after a word was selected, a screen with the
definition would be shown. This would require the laborious preparation of
1000 screens for the definitions and more than 100 menu screens to access
them. A more powerful system than DVD simply could read the text of a definition
from a database file and display it on a generic definition screen.
The use of DVD-Video for education, productivity, games, and the like is
disappointingly limited. The feature set was clearly designed from the limited
goals of on-screen menus, simple branching, and karaoke. Clever use of
the rudimentary interactive features of DVD can accomplish a truly surprising
amount, but most producers will be hard pressed to put in the
extra time and effort required, thus resulting in reduced usability. A DVD-
Video cookbook, for instance, may provide a simple index search of ingredients
or dishes that would include chickpeas and stew but would
frustrate someone looking for garbanzo beans or goulash and may not
even include the carrots that are in the stew.
Limited Graphics
The subpicture feature of DVD could be extended far beyond simple captions,
menus, and crude animation if it were not limited to four colors and
four transparency levels at a time. Much richer visual interaction could be
achieved with more colors. Advanced features such as sprites and rudimentary
three-dimensional (3D) capabilities also would expand DVD’s
repertoire.
The designers obviously chose to limit the subpicture format to save cost
and bandwidth, but even a small improvement of 16 simultaneous colors
would have made for significantly better-looking subtitles, more sophisticated
highlighting, and a superior graphic overlay environment.
Small Discs
Chapter 7
Part of the appeal of DVD is its small, convenient size. Ironically, however,
this is also a drawback. People are psychologically averse to paying the
same amount for something smaller. Even though the smaller item may be
better, the larger item somehow seems to be worth more.
The small size of DVDs also limits the cover art. Gone are the days of
innovative art on LP jackets or good-sized movie art and descriptive text on