--- a/reqs/Overview.html	Wed Jul 11 13:27:11 2012 +0100
+++ b/reqs/Overview.html	Fri Jul 13 12:12:54 2012 +0100
@@ -129,12 +129,12 @@
       <h4>Notes and Implementation Considerations</h4>
       
       <ol>
-        <li><p>This scenario is a good example of the need for audio capture (from line in, internal microphone or other inputs).</p></li>
+        <li><p>This scenario is a good example of the need for audio capture (from line in, internal microphone or other inputs). We expect this to be provided by <a href="http://www.w3.org/TR/html-media-capture/" title="HTML Media Capture">HTML Media Capture</a>.</p></li>
         <li><p>This scenario is heavily inspired from <a href="http://tools.ietf.org/html/draft-ietf-rtcweb-use-cases-and-requirements-06#section-4.2.1">the first scenario in WebRTC's Use Cases and Requirements document</a>. Most of the technology described by this scenario should be covered by the <a href="http://www.w3.org/TR/webrtc/" title="WebRTC 1.0: Real-time Communication Between Browsers">Web Real-Time Communication API</a>. The scenario illustrates, however, a technical requirement for processing of the audio signal at both ends (capture of the user's voice and output of its correspondents' conversation).</p></li>
-        <li><p>The processing effects needed by this scenario would include:</p>
+        <li><p>The processing capabilities needed by this scenario include:</p>
           <ul>
-            <li>Controlling the gain (mute, pause and volume) of several audio sources</li>
-            <li>Filtering (EQ, voice enhancement)</li>
+            <li><em>Controlling the gain</em> (mute, pause and volume) of several audio sources</li>
+            <li><em>Filtering</em> (EQ, voice enhancement)</li>
             <li>Pitch, speed distortion</li>
           </ul>
         </li>
@@ -143,18 +143,26 @@
       </section>
       
       <section>
-      <h3>UC 2: HTML5 game with audio effects, music</h3>
-      <p>A user is playing a 3D first-person adventure game in a web browser on their mobile device. 
-      </p><p>The game includes a musical background which loops seamlessly, and transitions smoothly from one music track to another as the player enters a house. 
-      </p><p>While walking in a corridor, the player can hear the muffled sound of a ticking grandfather's clock. Following the direction of the sound and entering a large hall, the sound of the clock becomes clear, reverberating in the large hall. At any time, the sound of the clock spatialized in real-time based on the position of the player's character in the room (relative to the clock) and the current camera angle. 
-      </p><p>As the soundscape changes, bringing a more somber, scary atmosphere to the scene, the player equips a firearm. Suddenly,  a giant snake springs from behind a corner, its hissing becoming a little louder as the snake turns its head towards the player. The weapon fires at the touch of a key, and the player can hear the sound of bullets in near-perfect synchronization with the firing, as well as the sound of bullets ricocheting against walls. The sounds are played immediately after the player presses the key, but the action and video frame rate can remain smooth even when a lot of sounds (bullets being fired, echoing and ricocheting, sound of the impacts, etc) are played at the same time. The snake is now dead, and many flies gather around it, and around the player, their fast buzz around the head sounding like racing cars on a circuit.
-      </p>
-      <h4>UC2 — Priority </h4>
-      <pre> <i>Priority: <b>HIGH</b></i>
-      </pre>
-      <p>… consensus reached during the teleconference on <a href="http://www.w3.org/2012/02/13-audio-minutes" title="http://www.w3.org/2012/02/13-audio-minutes">13 Feb 2012</a>. 
-      </p><p>This is something we are getting overwhelming amounts of feedback on - people are trying to build games with convincing, rich audio on the web.
-      </p>
+      <h3>Scenario 2: 3D game with music and convincing sound effects</h3>
+      <p>A user is playing a 3D first-person adventure game on their mobile device. The game is built entirely using open web technologies, and can run in the mobile device's web browser or as a packaged web application.</p>
+      <p>The game includes a musical background which loops seamlessly, and transitions smoothly from one music track to another as the player enters a house.</p>
+      <p>While walking in a corridor, the player can hear the muffled sound of a ticking grandfather's clock. Following the direction of the sound and entering a large hall, the sound of the clock becomes clear, reverberating in the large hall. At any time, the sound of the clock spatialized in real-time based on the position of the player's character in the room (relative to the clock) and the current camera angle.</p>
+      <p>As the soundscape changes, bringing a more somber, scary atmosphere to the scene, the player equips a firearm. Suddenly,  a giant snake springs from behind a corner, its hissing becoming a little louder as the snake turns its head towards the player. The weapon fires at the touch of a key, and the player can hear the sound of bullets in near-perfect synchronization with the firing, as well as the sound of bullets ricocheting against walls. The sounds are played immediately after the player presses the key, but the action and video frame rate can remain smooth even when a lot of sounds (bullets being fired, echoing and ricocheting, sound of the impacts, etc) are played at the same time. The snake is now dead, and many flies gather around it, and around the player's character, buzzing and zooming in the virtual space of the room.</p>
+
+      <h4>Notes and Implementation Considerations</h4>
+      
+      <ol>
+      <li><p>The need for HTML games to include rich, convincing sound has been the subject of much input to the W3C Audio Working Group. The group considers it a very high priority use case.</p></li>
+      <li><p>This scenario encompasses a very large number of requirements for the management and processing of audio in the Open Web Platform. We will note the following:</p>
+        <ul>
+          <li><p>The looping music background to the game could possibly be created with the <a href="http://www.w3.org/TR/html5/the-audio-element.html#the-audio-element" title="4.8.7 The audio element &#8212; HTML5">HTML5 &lt;audio&gt; element</a>. The ability to transition smoothly from one music track to another suggests, however, a capability for <em>mixing and filtering multiple sources</em> not already offered by HTML5.</p></li>
+          <li><p>The scenario illustrates many aspects of the creation of a credible soundscape. The game character is evolving in a virtual three-dimensional environment and the soundscape is, at all time, spatialized: a <em>panning model</em> can be used to spatialize sound sources in the game; <em>obstruction / occlusion</em> modelling is used to muffle the sound of the clock going through walls, and the sound of flies buzzing around would need <em>Doppler Shift</em> simulation to sound believable.</p></li>
+          <li><p>As the soundscape changes from small room to large hall, the game benefits from the <em>simulation of acoustic spaces</em>, possibly through the use of a <em>convolution engine</em> for high quality room effects.</p></li> 
+          <li><p>Many sounds in the scenario are triggered by events in the game, and would need to be played with low latency. The sound of the bullets as they are fired and ricochet against the walls, in particular, illustrate a requirement for <em>basic polyphony</em> and  <em>high-performance playback and processing of many sounds</em>.</p></li>
+        </ul>
+      </li>
+      </ol>
+
 
     </section>