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Jun 22, 2021
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Define TTS enhancements in a working group note #1700

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2dbf73f
remove pls lexicon section and remove entry from core media types table
mattgarrish Jun 11, 2021
f34029f
change references to core pls section to the pls specification and th…
mattgarrish Jun 11, 2021
cd28a2b
remove pls file from manifest cmt example
mattgarrish Jun 11, 2021
9b9c3f7
s/div/aside/
mattgarrish Jun 11, 2021
e7fb902
remove pls lexicon support requirements for reading systems
mattgarrish Jun 11, 2021
12564f1
Merge branch 'main' into editorial/issue-1690
mattgarrish Jun 17, 2021
615b4a3
move ssml and css speech requirements to the new tts note
mattgarrish Jun 18, 2021
5afac77
Merge branch 'editorial/issue-1690' of https://github.com/w3c/epub-sp…
mattgarrish Jun 18, 2021
bbee8b9
Merge branch 'main' into editorial/issue-1690
mattgarrish Jun 18, 2021
7ee8b72
fix bad id plus minor typos
mattgarrish Jun 18, 2021
31f3b3d
Merge branch 'editorial/issue-1690' of https://github.com/w3c/epub-sp…
mattgarrish Jun 18, 2021
cc1c614
update intro to clarify pls and ssml can be used independently and im…
mattgarrish Jun 19, 2021
2fdc027
minor tweak to pls intro to focus less on ssml
mattgarrish Jun 20, 2021
5620f74
add examples
mattgarrish Jun 21, 2021
9cca3df
fix status to ed
mattgarrish Jun 21, 2021
f1ddbfb
updated examples
mattgarrish Jun 22, 2021
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227 changes: 14 additions & 213 deletions epub33/core/index.html
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Original file line number Diff line number Diff line change
Expand Up @@ -593,14 +593,6 @@ <h4>Namespaces</h4>
<code>http://www.idpf.org/2007/ops</code>
</td>
</tr>
<tr>
<td>
<code>ssml</code>
</td>
<td>
<code>https://www.w3.org/2001/10/synthesis</code>
</td>
</tr>
</table>
</section>
</section>
Expand Down Expand Up @@ -910,13 +902,6 @@ <h5>Supported Media Types</h5>
</td>
<td>EPUB Media Overlay documents</td>
</tr>
<tr>
<td id="cmt-pls">
<code>application/pls+xml</code>
</td>
<td> [[PRONUNCIATION-LEXICON]] </td>
<td><a>Text-to-Speech</a> (TTS) Pronunciation lexicons</td>
</tr>
</tbody>
</table>
<div class="issue" data-number="645">
Expand Down Expand Up @@ -2790,7 +2775,7 @@ <h6>The <code>item</code> Element</h6>

<h6>Examples</h6>

<div class="example" id="example-manifest-cmt">
<aside class="example" id="example-manifest-cmt">

<p>The following example shows a <code>manifest</code> that contains only <a>Core Media
Type Resources</a>.</p>
Expand Down Expand Up @@ -2836,12 +2821,9 @@ <h6>Examples</h6>
&lt;item id="css"
href="./style/book.css"
media-type="text/css"/&gt;
&lt;item id="pls"
href="./speech/dict.pls"
media-type="application/pls+xml"/&gt;
&lt;/manifest&gt;
</pre>
</div>
</aside>

<aside class="example" id="example-manifest-flbk">
<p>The following example shows a <code>manifest</code> that references two <a>Foreign
Expand Down Expand Up @@ -3554,140 +3536,6 @@ <h5>RDFa</h5>
</div>
</section>

<section id="sec-xhtml-ssml-attrib">
<h5>SSML Attributes</h5>

<section id="sec-cd-ssml-intro" class="informative">
<h6>Introduction</h6>

<p>The W3C Speech Synthesis Markup Language [[SSML]] is a language used for assisting
<a>Text-to-Speech</a> (TTS) engines in generating synthetic speech. Although SSML is
designed as a standalone document type, it also defines semantics suitable for use
within other markup languages.</p>

<p>This specification recasts the [[SSML]] <a
href="https://www.w3.org/TR/2010/REC-speech-synthesis11-20100907/#S3.1.10"
><code>phoneme</code> element</a> as two attributes — <code>ssml:ph</code> and
<code>ssml:alphabet</code> — and makes them available within XHTML Content
Documents.</p>

<div class="note">
<p>For more information on EPUB 3 features related to synthetic speech, refer to <a
href="https://www.w3.org/TR/epub-overview-33/#sec-tts">Text-to-speech</a>
[[EPUB-OVERVIEW-33]].</p>
</div>
</section>

<section id="sec-cd-ssml-ph-attrib">
<h6>The <code>ssml:ph</code> attribute</h6>

<p>The <code>ssml:ph</code> attribute specifies a phonemic/phonetic pronunciation of the
text represented by its carrying element.</p>

<dl class="elemdef" id="attrdef-ssml-ph">
<dt>Attribute Name</dt>
<dd>
<p>
<code>ph</code>
</p>
</dd>
<dt>Namespace</dt>
<dd>
<p>
<code>https://www.w3.org/2001/10/synthesis</code>
</p>
</dd>
<dt>Usage</dt>
<dd>
<p><a href="https://html.spec.whatwg.org/multipage/dom.html#global-attributes"
>Global attribute</a>. EPUB Creators MAY specify on all elements with which
they can logically associate a phonetic equivalent (e.g., elements that contain
textual information).</p>
<p>EPUB Creators MUST NOT specify the attribute on a descendant of an element that
already carries this attribute.</p>
</dd>
<dt>Value</dt>
<dd>
<p>A phonemic/phonetic expression, syntactically valid with respect to <a
href="#sec-cd-ssml-alphabet-attrib">the phonemic/phonetic alphabet
used</a>.</p>
</dd>
</dl>

<p>This attribute inherits all the semantics of the [[SSML]] <code>phoneme</code> element <a
href="https://www.w3.org/TR/2010/REC-speech-synthesis11-20100907/#S3.1.10"
><code>ph</code></a> attribute, with the following addition:</p>

<ul class="conformance-list">
<li>
<p id="ssml-ph-concat">When the <code>ssml:ph</code> attribute appears on an element
that has text node descendants, the corresponding document text to which the
pronunciation applies is the string that results from concatenating the
descendant text nodes, in document order. The specified phonetic pronunciation
MUST therefore logically match the element's textual data in its entirety (i.e.,
not just an isolated part of its content).</p>
</li>
</ul>
</section>

<section id="sec-cd-ssml-alphabet-attrib">
<h6>The <code>ssml:alphabet</code> attribute</h6>

<p>The <code>ssml:alphabet</code> attribute specifies which phonemic/phonetic pronunciation
alphabet is used in the value of the <a href="#attrdef-ssml-ph"><code>ssml:ph</code></a>
attribute.</p>

<dl class="elemdef" id="attrdef-ssml-alphabet">
<dt>Attribute Name</dt>
<dd>
<p>
<code>alphabet</code>
</p>
</dd>
<dt>Namespace</dt>
<dd>
<p>
<code>https://www.w3.org/2001/10/synthesis</code>
</p>
</dd>
<dt>Usage</dt>
<dd>
<p><a href="https://html.spec.whatwg.org/multipage/dom.html#global-attributes"
>Global attribute</a>. EPUB Creators MAY specify on any element.</p>
</dd>
<dt>Value</dt>
<dd>
<p>The name of the pronunciation alphabet used in the value of <a
href="#attrdef-ssml-ph"><code>ssml:ph</code></a> (inherited).</p>
</dd>
</dl>

<p>This attribute inherits all the semantics of the [[SSML]] <code>phoneme</code> element <a
href="https://www.w3.org/TR/2010/REC-speech-synthesis11-20100907/#S3.1.10"
><code>alphabet</code></a> attribute, with the following addition:</p>

<ul class="conformance-list">
<li>
<p id="ssml-alphabet-inherit">The value of the <code>ssml:alphabet</code> attribute
is inherited in the document tree. The pronunciation alphabet used in a given
<code>ssml:ph</code> attribute value is determined by locating the first
occurrence of the <code>ssml:alphabet</code> attribute starting with the element
on which the <code>ssml:ph</code> attribute appears, followed by the nearest
ancestor element.</p>
</li>
</ul>

<div class="note">
<p>Although the [[SSML]] specification refers to a registry of alphabets, one has not
been published. As the charter of the W3C Voice Browser Working Group has expired,
the Working Group does not anticipate the publication of such a registry. EPUB
Creators therefore should reference Reading System support documentation to
determine what alphabet values they support. Some common alphabets include x-JEITA
(also x-JEITA-IT-4002 and x-JEITA-IT-4006) and x-sampa.</p>
</div>
</section>
</section>

<section id="sec-xhtml-content-switch">
<h5>Content Switching (Deprecated)</h5>

Expand Down Expand Up @@ -4306,58 +4154,6 @@ <h4 id="confreq-cd-scripted-flbk">Scripting Fallbacks</h4>
</section>

</section>


<section id="sec-pls">
<h3>Pronunciation Lexicons</h3>

<p>The W3C Pronunciation Lexicon Specification (PLS) [[PRONUNCIATION-LEXICON]] defines syntax and
semantics for XML-based pronunciation lexicons to be used by Automatic Speech Recognition and
<a>Text-to-Speech</a> (TTS) engines.</p>

<p id="confreq-cd-pls-xht">EPUB Creators MAY associate zero or more PLS Documents with an <a>XHTML
Content Document</a>.</p>

<p id="confreq-cd-pls-assoc">To associate a PLS Document with an <a>XHTML Content Document</a>, EPUB
Creators MUST use the [[HTML]] <a
href="https://html.spec.whatwg.org/multipage/semantics.html#the-link-element"
><code>link</code></a> element with its <code>rel</code> attribute set to
"<code>pronunciation</code>" and its <code>type</code> attribute set to the media type
"<code>application/pls+xml</code>".</p>

<p id="confreq-cd-pls-assoc-lang">EPUB Creators SHOULD specify the <code>link</code> element
<code>hreflang</code> attribute on each <code>link</code>, and its value MUST match <a
href="https://www.w3.org/TR/2008/REC-pronunciation-lexicon-20081014/#S4.1">the language for
which the pronunciation lexicon is relevant</a> [[PRONUNCIATION-LEXICON]] when specified.</p>

<aside class="example">
<p>The following example shows two <abbr title="Pronunciation Lexicon Specification">PLS</abbr>
documents (one for Chinese and one for Mongolian) associated with an XHTML Content Document.</p>
<pre>
&lt;html … &gt;
&lt;head&gt;
…
&lt;link rel="pronunciation" type="application/pls+xml" hreflang="zh" href="../speech/zh.pls"/&gt;
&lt;link rel="pronunciation" type="application/pls+xml" hreflang="mn" href="../speech/mn.pls"/&gt;
&lt;/head&gt;
…
&lt;/html&gt;</pre>
</aside>

<p id="confreq-cd-pls-docprops-schema">PLS Documents MUST be valid to the RELAX NG schema available at
the URL <a href="https://www.w3.org/TR/2008/REC-pronunciation-lexicon-20081014/pls.rng"
><code>https://www.w3.org/TR/2008/REC-pronunciation-lexicon-20081014/pls.rng</code></a>
[[PRONUNCIATION-LEXICON]].</p>

<p id="confreq-cd-pls-fileprops-name">PLS Documents SHOULD use the file extension <code class="filename"
>.pls</code>.</p>

<div class="note">
<p>For more information on EPUB 3 features related to synthetic speech, refer to <a
href="https://www.w3.org/TR/epub-overview-33/#sec-tts">Text-to-speech</a>
[[EPUB-OVERVIEW-33]].</p>
</div>
</section>
</section>
<section id="sec-nav">
<h2>EPUB Navigation Document</h2>
Expand Down Expand Up @@ -7868,10 +7664,6 @@ <h2>Security and Privacy</h2>
<p>The <a href="#sec-epub-type-attribute">expression of structural semantics</a> in HTML and SVG
only allows the annotation of elements.</p>
</li>
<li>
<p>A <a href="#sec-xhtml-ssml-attrib">reformulation of SSML</a> as HTML attributes only allows the
expression of phonemes and pronunciation alphabets.</p>
</li>
<li>
<p>The <a href="https://www.w3.org/TR/epub-rs-33/#app-epubReadingSystem"
><code>epubReadingSystem</code> object</a> [[EPUB-RS-33]] only allows EPUB Creators to
Expand Down Expand Up @@ -9483,11 +9275,20 @@ <h3>Substantive Changes since the <a href="https://www.w3.org/TR/2021/WD-epub-33
-->

<ul>
<li>18-June-2021: Moved requirements for authoring SSML, PLS lexicons and CSS 3 Speech to the <a
href="https://www.w3.org/TR/epub-3-tts">EPUB 3 Text-to-Speech Enhancements</a> note. The
ability to use these technologies in EPUB 3 Publications remains unchanged. See <a
href="https://github.com/w3c/epub-specs/issues/1690">issue 1690</a>.</li>
<li>16-June-2021: Absolute URLs with <code>file</code> scheme SHOULD NOT be used on manifest items.
See <a href="https://github.com/w3c/epub-specs/issues/1688">issue 1688</a>.</li>
<li>11-June-2021: The section on adding PLS lexicons to HTML has been removed due to a lack of
real-world support. It is still valid to link lexicon files and fallbacks are not required, but
the practice is no longer detailed as it is no different than linking any other type of resource
in HTML. See <a href="https://github.com/w3c/epub-specs/issues/1690">issue 1690</a>.</li>
<li>31-May-2021: Require Unicode normalization and full case folding (in this order) for file name
uniqueness comparisons. See <a href="https://github.com/w3c/epub-specs/issues/1631">issue 1631</a>
and <a href="https://github.com/w3c/epub-specs/pull/1648">pull request 1648</a>.</li>
uniqueness comparisons. See <a href="https://github.com/w3c/epub-specs/issues/1631">issue
1631</a> and <a href="https://github.com/w3c/epub-specs/pull/1648">pull request
1648</a>.</li>
<li>31-May-2021: Confirmed that SVG Content Documents do not have to be valid to the SVG
specification, only meet the well-formedness and ID requirements currently referenced and the
restrictions imposed by this specification. See <a
Expand Down Expand Up @@ -9567,7 +9368,7 @@ <h3>Substantive changes since <a href="https://www.w3.org/publishing/epub/epub-s
specifically whitespace handling. See <a href="https://github.com/w3c/epub-specs/issues/1528"
>issue 1528</a>.</li>
<li>17-Feb-2020: File extension recommendations have been removed (affects the Package Document,
XHTML Content Documents, PLS Lexicons and Media Overlay Documents). See <a
XHTML Content Documents, Media Overlay Documents). See <a
href="https://github.com/w3c/epub-specs/issues/1294">issue 1294</a>.</li>
<li>15-Feb-2021: Clarified that <code>nav</code> elements without an <code>epub:type</code>
attribute are not subject to the EPUB Navigation Document's content model restrictions. See <a
Expand Down
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