Improved and updated documentation about accessibility

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/branches/Temp_Accessibility@829769 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 30 insertions, 36 deletions

diff --git a/src/documentation/content/xdocs/trunk/accessibility.xml b/src/documentation/content/xdocs/trunk/accessibility.xml
index e7e49d7c0..1eb78264b 100644
--- a/src/documentation/content/xdocs/trunk/accessibility.xml
+++ b/src/documentation/content/xdocs/trunk/accessibility.xml
@@ -29,13 +29,12 @@
         <a href="http://en.wikipedia.org/wiki/Accessibility">accessibility</a>
         features of Apache FOP.
         <a href="http://www.section508.gov/">Section 508</a> defines accessibility in the context
-        of electronic documents for the US but it impacts also other countries.
+        of electronic documents for the USA but other countries have similar requirements.
       </p>
       <p>
-        These features are concentrated exclusively on PDF output
-        (Tagged PDF). There are certain implementation limitations that need to be observed
-        and certain actions are necessary by the content creator to ensure that FOP can create
-        a truly accessible document. 
+        Accessibility features are available only for the PDF output format and there are some 
+        implementation limitations. Also, certain actions must be undertaken by the content creator 
+        to ensure that FOP can create a truly accessible document. 
       </p>
     </section>
     <section>
@@ -43,7 +42,7 @@
       <p>There are 3 ways to enable accessibility:</p>
       <ol>
         <li>
-          <strong>Command line:</strong> The command line option -a turns on accessibility.
+          <strong>Command line:</strong> The command line option -a turns on accessibility:
           <code>fop -a -fo mydocument.fo -pdf mydocument.pdf</code>            
         </li>
         <li>
@@ -60,55 +59,55 @@
         </li>
       </ol>
       <p>
-        As mentioned, enabling accessibility currently only changes the way PDFs are generated.
-        Internally, FOP maintains a reduced structure tree of the document so the target format
-        viewer can ultimately reconstruct the natural reading order of the document. This is
-        important for document readers that produce an aural representation of the content.
+        When accessibility is enabled, additional information relating to the logical structure of 
+        the document is added to the PDF. That information allows the PDF viewer (or a 
+        text-to-speech application) to retrieve the natural reading order of the document.
       </p>
-      <p>
-        Hint: You may need to adjust the Java heap size in order to process larger files.
-      </p> 
+      <note>The processing of the logical structure is memory-hungry. You may need to adjust the 
+        Java heap size in order to process larger files.</note>
     </section>
     <section id="source">
       <title>Changes to your XSL-FO input files</title>
       <p>
         Apache FOP cannot automatically generate accessible PDFs. Some of the work can only be
         performed by the content provider. Following are some changes that may be necessary to
-        your XSL-FO content so the generate documents that are truly accessible.
+        your XSL-FO content in order to generate really accessible documents:
       </p>
       <ul>
-        <li>Table cells require a table row as the parent.</li>
+        <li>Table cells must have a table row as their parent.</li>
         <li>
-          Ensure that the order of <code>fo:block-container</code> in a page corresponds to
-          the reading order.
+          Images must have an alternate text: use the <code>fox:alt-text</code> extension attribute 
+          (in the <a href="extensions.html#fox-namespace">fox namespace</a>) on 
+          <code>fo:external-graphic</code> and <code>fo:instream-foreign-object</code> to specify a 
+          short text describing the image.
         </li>
         <li>
-          Alternate text for images: The attribute <code>fox:alt-text</code> has been added
-          for <code>fo:external-graphic</code> and <code>fo:instream-foreign-object</code>.
+          Ensure that the order of <code>fo:block-container</code> elements in a page corresponds to
+          the reading order.
         </li>
         <li>
           Specify the natural language of the document using the language and country properties
-          (or via the xml:lang shorthand property).
+          (or via the <code>xml:lang</code> shorthand property).
         </li>
       </ul>
     </section>
     <section id="testing">
       <title>Testing</title>
       <p>
-        Accessible PDFs can be tested, for example, using Adobe Acrobat Professional. Its
-        Accessibility Check creates a report indicating any deficiencies with a PDF document.
-        Alternatively, you can just let a screen reader read the document out aloud.
+        Accessible PDFs can be tested, for example, using Adobe Acrobat Professional. Its 
+        Accessibility Check feature creates a report indicating any deficiencies with a PDF 
+        document. Alternatively, you can just let a screen reader read the document aloud.
       </p>
     </section>
     <section id="limitations">
       <title>Limitations</title>
       <p>
-        Accessibility support in Apache FOP is relatively new, so naturally, there are certain
+        Accessibility support in Apache FOP is relatively new, so there are certain
         limitations. Please help us identify and close any gaps.
       </p>
       <ul>
         <li>
-          The natural language can currently only be specified on the page-sequence level. The
+          The natural language can currently only be specified at the page-sequence level. The
           document language is derived from the language of the first page-sequence. It is
           currently not possible to override the language inside the content below the
           page-sequence level.
@@ -118,7 +117,7 @@
         </li>
         <li>
           SVG graphics (or images in general) are treated as a single figure. Text contained in
-          SVGs is not accessible. It's only possible to work with fox:alt-text.
+          SVGs is not accessible. It's only possible to work with <code>fox:alt-text</code>.
         </li>
         <li>
           XSL-FO's role property is currently not supported. It could theoretically be used to
@@ -129,28 +128,23 @@
           The side regions (region-before, region-after etc.) are currently not specially
           identified. Screen readers may read their content at page changes.
         </li>
-        <li>
-          The accessibility features are only available with PDF output and only if the
-          new output implementation based on the intermediate format (PDFDocumentHandler) is used.
-          Accessibility (Tagged PDF) is not supported by the legacy PDFRenderer.
-        </li>
       </ul>
     </section>
     <section id="links">
       <title>Related Links</title>
       <p>
-        We don't provide a comprehensive guide to create accessible documents. Below are some
-        links with additional resources around the topic.
+        Many resources providing guidance about creating accessible documents can be found on the 
+        web. Here are a few links, along with additional resources around the topic:
       </p>
       <ul>
-        <li><a href="pdfa.html">PDF/A support in Apache FOP</a></li>
         <li><a href="http://www.section508.gov/">US Government - Website on Section 508</a></li>
         <li><a href="http://en.wikipedia.org/wiki/Accessibility">Wikipedia on Accessibility in general</a></li>
         <li><a href="http://en.wikipedia.org/wiki/Portable_Document_Format#Accessibility">Wikipedia on Accessibility in PDF</a></li>
         <li>
-          <a href="http://partners.adobe.com/public/developer/en/pdf/PDFReference.pdf">PDF Reference 1.4</a> 
-          (lookup chapters 9.7 "Tagged PDF" and 9.8 "Accessibility Support")
+          <a href="http://partners.adobe.com/public/developer/en/pdf/PDFReference.pdf">PDF 
+            Reference 1.4</a> (look up chapters 9.7 "Tagged PDF" and 9.8 "Accessibility Support")
         </li>
+        <li><a href="pdfa.html">PDF/A support in Apache FOP</a></li>
         <li><a href="http://wiki.apache.org/xmlgraphics-fop/PDF_Accessibility">Developer-oriented details on the accessibility features (on the Wiki)</a></li>
       </ul>
     </section>