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<title>Chapter 3. It’s Alive: Rich Content Accessibility</title>
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<h2 class="title" data-origPath="/html/body/section/h2">Chapter 3. It’s Alive: Rich Content Accessibility</h2>
<p data-origPath="/html/body/section/p[1]">It’s now time to turn our attention to the features that EPUB 3 introduces to expand
on the traditional reading experience; the excitement around EPUB 3 doesn’t come
from text and images, after all.</p>
<p data-origPath="/html/body/section/p[2]">This section takes focus on the dynamic aspects of EPUB 3. Rich media, audio
integration, and scripted interactivity are all new features that have been added in
this version. Some of these features, like audio and video support and scripting,
introduce new accessibility challenges, while others, like overlaying audio on your
text content and enhancing text-to-speech rendering, improve access for all. (The
members of this latter group are also commonly referred to as accessibility
superstructures, because they are added on top of core EPUB content to enhance
accessibility.)</p>
<p data-origPath="/html/body/section/p[3]">But let’s get back to business of being accessible…</p>
<h2 class="title" id="_the_sound_and_the_fury_audio_and_video" data-origPath="/html/body/section/section/h2">The Sound and the
Fury: Audio and Video</h2>
<p data-origPath="/html/body/section/section/p[1]">The new built-in support for audio and video in EPUB 3 has its pros and cons from
both mainstream and accessibility perspectives. The elements simplify the
process of embedding multimedia, but come at the expense of complicating
interoperability, and by extension accessibility—specifically as relates to
video.</p>
<p data-origPath="/html/body/section/section/p[2]">There is currently no solution for the general accessibility problem of video,
namely that not all reading systems may natively play your content. The video
element permits any video format to be specified, but not all reading systems
will support all formats. Support for one or both of the VP8 codec (used in WebM
video) and H.264 codec is encouraged in the EPUB specification to improve
interoperability, but you still have to be aware that if you have an EPUB with
WebM video and a reading system that only supports H.264 you won’t be able to
view the video.</p>
<p data-origPath="/html/body/section/section/p[3]">Until consensus on codec and container support can be found, there is no easy
solution to this problem. You can try targeting your video format to the
distribution channel, but that assumes that the readers buying from the online
bookstore will use the reading system you expect, which isn’t a given. Even
seemingly-simple solutions, like duplicating the format of all video content,
are only feasible on small scales and don’t take into account the potential cost
involved.</p>
<aside class="note" title="Note" data-origPath="/html/body/section/section/aside[1]">
<h3 class="title">Note</h3>
<p>It is possible that some reading systems may provide no video support at
all.</p>
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<p data-origPath="/html/body/section/section/p[4]">But that was more of an aside to say that if you don’t think accessibility is
worth your time and effort, consider there may be a larger audience than you
might expect that could be relying on your fallbacks in the near term.</p>
<p data-origPath="/html/body/section/section/p[5]">Playability issues aside, though, HTML5 is still a leap forward in terms of
multimedia support. It’s fair to assert that no one will miss plugins for
rendering audio and video content, certainly not on the accessibility side of
the fence. From roach-motel players that let you navigate in but never let you
leave to players lacking keyboard support to utter black holes, the
accessibility community typically does not have a lot of good things to say
about multimedia as deployed on the Web.</p>
<p data-origPath="/html/body/section/section/p[6]">That the new native elements can be controlled by the reading system in EPUB 3
should translate into greater accessibility, however. To enable the default
system controls, you need only add a <code class="literal">controls</code>
attribute to the element:</p>
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