CHAPTER 9
756
Multimedia Features
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Media objects may have multiple
renditions,
which can be chosen at play-time
based on considerations such as available bandwidth.
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Document authors can control play-time requirements, such as which player
software should be used to play a given media object.
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Media objects can be played in various ways; for example, in a floating window
as well as in a region on a page.
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Future extensions to the media constructs can be handled in an appropriate
manner by current viewer applications. Authors can control how old viewers
treat future extensions.
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Document authors can adapt the use of multimedia to accessibility require-
ments.
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On-line media objects can be played efficiently, even when very large.
The following list summarizes the multimedia features and indicates where each
feature is discussed:
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jects are suitable for playing on a particular system.
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Rendition actions (see “Rendition Actions” on page 668) are used to begin the
playing of multimedia content.
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A rendition action associates a screen annotation (see “Screen Annotations” on
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Renditions are of two varieties: media renditions (see “Media Renditions” on
renditions (see “Selector Renditions” on page 763) that enables choosing which
of a set of media renditions should be played.
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Media renditions contain entries that specify what should be played (see Sec-
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are referenced by the major objects listed above.
Note:
Some of the features described in the following sections have references to cor-
responding elements in the Synchronized Multimedia Integration Language (SMIL
2.0) standard (see the Bibliography).