steve: added another web can example to deal with case where time updates not available.

steve: added another web can example to deal with case where time
updates not available.

http://dev.w3.org/cvsweb/html5/alt-techniques/Overview.html?r1=1.20&r2=1.21&f=h

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RCS file: /sources/public/html5/alt-techniques/Overview.html,v
retrieving revision 1.20
retrieving revision 1.21
diff -u -d -r1.20 -r1.21
--- Overview.html 23 Apr 2010 15:40:56 -0000 1.20
+++ Overview.html 5 May 2010 11:36:26 -0000 1.21
@@ -237,7 +237,7 @@
  </head>
 <body>
 <h1>HTML5:  Techniques for providing useful text alternatives</h1>
-<h2>Editor's Draft 23rd April 2010</h2>
+<h2>Editor's Draft 5th May 2010</h2>
 <h3>Editor:</h3>
 <p><a href="mailto:sfaulkner@paciellogroup.com">Steve Faulkner</a>, The Paciello Group.</p>
 <hr>
@@ -961,8 +961,50 @@
 <strong>&lt;p id=&quot;s2&quot;&gt;In the foreground of the image are the safety rails on the flat part of the roof. 
 Nearby there are low rise industrial buildings, beyond are blocks of flats. 
 In the distance there's a church steeple.&lt;/p&gt;</strong>  
-&lt;/figure&gt;  </pre>
+&lt;/figure&gt;  
+</pre>
+</div>
+<h4>Example 10.3</h4>
+<p>The previous web cam examples rely upon the correct time and and date information being inserted via scripting each time the image is updated. If this is not possible, the text alternative should instead include a brief description of the text information that changes each time the image is updated. 2 versions are provided the first includes the description as part of the alt attribute content the second includes it as part of the longer text alternative below the image. both examples use inlcude the longer text alternative in a paragraph associated with the image using <code>aria-describedby</code>. </p>
+<p>Context: A webcam image updated every hour, with a viewpoint from the top of Sopwith house, looking north.</p>
+<div class="example">
+  <p><strong>Image example in context:</strong></p>
+  <div class="element1">
+    <p><img src="images/webcam1.jpg" alt="Sopwith house weather cam. Includes date and time information indicating when the image was taken." width="296" height="225"></p>
+    <p>View from the top of Sopwith house, looking towards North Kingston.</p>
+    <p>This image is updated every hour.</p>
+    <p>View the <a href="http://news.bbc.co.uk/weather/forecast/4296?area=Kingston">latest weather details</a> for Kingston upon Thames.</p>
+    <p><strong>Sopwith House Weather cam image description:</strong></p>
+    <p>In the foreground are the safety rails on the flat part of the roof. Nearby there are low rise industrial buildings, 
+      beyond are blocks of flats. In the distance there's a church steeple.</p>
+  </div>
+  <p><strong>Code Example 1:</strong></p>
+  <pre>&lt;figure&gt;   
+&lt;img src="webcam1.jpg" <strong>alt="Sopwith house weather cam. Includes date and time information indicating when the image was taken."</strong> <strong>aria-describedby=&quot;s1 s2&quot;</strong>&gt;  
+&lt;figcaption id=&quot;s1&quot;&gt;View from the top of Sopwith house, looking towards north Kingston.&lt;/figcaption&gt;
+&lt;p&gt;This image is updated every hour.&lt;/p&gt;
+&lt;p&gt;View the &lt;a href=&quot;http://news.bbc.co.uk/weather/forecast/4296?area=Kingston&quot;&gt;
+latest weather details&lt;/a&gt; for Kingston upon Thames.&lt;/p&gt; 
+&lt;p&gt;&lt;strong&gt;Sopwith House Weather cam image description:&lt;/strong&gt;&lt;/p&gt;
+<strong>&lt;p id=&quot;s2&quot;&gt;In the foreground of the image are the safety rails on the flat part of the roof. 
+Nearby there are low rise industrial buildings, beyond are blocks of flats. 
+In the distance there's a church steeple.&lt;/p&gt;</strong>  
+&lt;/figure&gt; </pre>
+  <p><strong>Code Example 2:</strong></p>
+  <pre>&lt;figure&gt;   
+&lt;img src="webcam1.jpg" <strong>alt="Sopwith house weather cam."</strong> <strong>aria-describedby=&quot;s1 s2&quot;</strong>&gt;  
+&lt;figcaption id=&quot;s1&quot;&gt;View from the top of Sopwith house, looking towards north Kingston.&lt;/figcaption&gt;
+&lt;p&gt;This image is updated every hour.&lt;/p&gt;
+&lt;p&gt;View the &lt;a href=&quot;http://news.bbc.co.uk/weather/forecast/4296?area=Kingston&quot;&gt;
+latest weather details&lt;/a&gt; for Kingston upon Thames.&lt;/p&gt; 
+&lt;p&gt;&lt;strong&gt;Sopwith House Weather cam image description:&lt;/strong&gt;&lt;/p&gt;
+<strong>&lt;p id=&quot;s2&quot;&gt;</strong>In the foreground of the image are the safety rails on the flat part of the roof. 
+Nearby there are low rise industrial buildings, beyond are blocks of flats. 
+In the distance there's a church steeple.<strong>
+ Across the top of the image is date and time information indicating when it was taken.&lt;/p&gt;</strong>  
+&lt;/figure&gt; </pre>
 </div>
+<p> </p>
 <h4>Related  techniques and resources</h4>
 <ul>
   <li>    <a href="http://www.w3.org/WAI/PF/aria-practices/#DescribedBy"><abbr title="Accessible Rich Internet Applications">WAI-ARIA</abbr> Authoring Practices 1.0, 4.1.2 Describing</a></li>

Received on Wednesday, 5 May 2010 11:37:13 UTC