epubjs
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Render ePub documents in the browser, across many devices
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<title>Chapter 3. It’s Alive: Rich Content Accessibility</title>
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<p data-origPath="/html/body/section/section/section/p[13]">I mentioned the difference between subtitles and captions at the outset, but
the <code class="literal">kind</code> attribute can additionally take the
following two values of note:</p>
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<li class="listitem"><p> descriptions — specifying this value indicates that
the track contains a text description of the video. A descriptions
track is designed to provide missing information to readers who can
hear the audio but not see the video (which includes blind and
low-vision readers, but also anyone for whom the video display is
obscured or not available). The track is intended to be voiced by a
text-to-speech engine. </p></li>
<li class="listitem"><p> chapters — a chapters track includes navigational
aid within the resource. If your audio or video is structured in a
meaningful way (e.g., scenes), adding a chapters track will enable
readers of all abilities to more easily navigate through it.
</p></li>
</ul>
<p data-origPath="/html/body/section/section/section/p[14]">But now I’m going to trip you up a bit. The downside of the <code class="literal">track</code> element that I’ve been trying to hold off
on is that it remains unsupported in browser cores as of writing (at least
natively), which means EPUB readers also may not support tracks right away.
There are some JavaScript libraries that claim to be able to provide support
now (polyfills, as they’re colloquially called), but that assumes the reader
has a JavaScript-enabled reading system.</p>
<p data-origPath="/html/body/section/section/section/p[15]">Embedding the tracks directly in your video resources is, of course, another
option if native support does not materialize right away.</p>
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