Rework Podcast on a Flight scenario.
--- a/reqs/Overview.html Fri Aug 10 13:05:12 2012 -0400
+++ b/reqs/Overview.html Fri Aug 10 13:29:01 2012 -0400
@@ -301,36 +301,31 @@
</section>
<section>
-
-
<h3>Podcast on a flight</h3>
- <p>A user is subscribed to a podcast, and has downloaded an audio book on
- his device.
- The audio files are stored locally on the user's computer or other
- device ready for off line use, giving simple and convenient access to
- episodic content, through a web browser.
- </p><p>The user is sitting in an airplane, for a 2 hours flight. The user opens
- his audio book in his HTML browser a sees that the episode he has
- selected lasts 3 hours.
- The user would like to be able to accelerate the speed of the audio
- book, without pitch distortion (i.e., voices not sounding like
- “chipmunks” when accelerated). He would like to set the audition time to
- 2 hours in order to finish the audio book before landing.
- </p><p>The web-page presents a graphic visualization of the speed, the total
- duration of the audio on a time line at the corresponding speed.
- The web-page also associates an audio speed changer interface provided
- by the web-page developer allowing the user to change the tempo of the
- speech and speed up audio files without changing the pitch. This lets
- the user drastically speed up speech speed without a "chipmunk" effect.
- </p><p>Another interface allows the user to set the duration of the audio,
- regarding its initial duration at normal speed, therefore changing its
- speed with pitch lock.
- The user may also tweak other settings like the tone and timbre to his
- taste.
- </p><p>This would be valuable features for book listeners who want to save time
- by accelerating audio books as well as podcasts.
- </p>
+ <p>A user is subscribed to a podcast, and has previously
+ downloaded an audio book on his device using the podcast's
+ web-based application. The audio files are stored locally on
+ the device, giving simple and convenient access to episodic
+ content whenever the user wishes to listen.</p>
+
+ <p>The user is sitting in an airplane for a 2-hour flight. The user opens
+ the podcast application in his HTML browser and sees that the episode he has
+ selected lasts 3 hours. The application offers a speed-up feature that allows
+ the speech to be delivered at a faster than normal speed without pitch distortion
+ ("chipmunk voices"). He sets the audition time to
+ 2 hours in order to finish the audio book before landing. He also sets the sound
+ control in the application to "Noisy Environment", causing the sound to be equalized
+ for greatest intelligibility in a noisy setting such as an airplane.</p>
+
+ <h4>Notes and Implementation Considerations</h4>
+ <ol>
+ <li><p>Local audio can be downloaded, stored and retrieved using the <a href="http://www.w3.org/TR/FileAPI/">HTML File API</a>.</p></li>
+ <li><p>This scenario requires a special audio transformation that can compress the duration of speech
+ without affecting overall timbre and intelligibility. In the Web Audio API this could be accomplished through
+ attaching custom processing code to a <code>JavaScriptAudioNode</code>.</p></li>
+ <li><p>The "Noisy Environment" setting could be accomplished through equalization features in the Web Audio API such as <code>BiquadFilterNode</code> or <code>ConvolverNode</code>.</p></li>
+ </ol>
</section>
<section>