Audio edits.
modified: audio.jd
Change-Id: Iffeace6ce6509b75329c1eecedc3745e4b323086
diff --git a/src/devices/audio.jd b/src/devices/audio.jd
index a64b7b7..9f6cfd0 100644
--- a/src/devices/audio.jd
+++ b/src/devices/audio.jd
@@ -116,7 +116,7 @@
</li>
<li>
<code>hardware/libhardware/include/hardware/audio_effect.h</code> - represents effects that can
- be applied to audio such as downmixing, echo, or noise supression.
+ be applied to audio such as downmixing, echo, or noise suppression.
</li>
</ul>
<p>See the implementation for the Galaxy Nexus at <code>device/samsung/tuna/audio</code> for an example.</p>
@@ -282,21 +282,20 @@
<code><li>android.media.MediaRecorder.AudioSource.DEFAULT</li></code>
</ul>
-<p>The default pre-processing effects that are applied for each <code>AudioSource</code> is
+<p>The default pre-processing effects that are applied for each <code>AudioSource</code> are
specified in the <code>/system/etc/audio_effects.conf</code> file. To specify
your own default effects for every <code>AudioSource</code>, create a <code>/system/vendor/etc/audio_effects.conf</code> file
and specify any pre-processing effects that you need to turn on. For an example,
-see the implementation for the Nexus 10 in <code>device/samsung/manta/audio_effects.conf</code>
+see the implementation for the Nexus 10 in <code>device/samsung/manta/audio_effects.conf</code></p>
<p class="warning"><strong>Warning:</strong> For the <code>VOICE_RECOGNITION</code> use case, do not enable
-the noise supression pre-processing effect. This effect is already turned off by default, but if you enable
-it in your own <code>audio_effects.conf</code> file, it is ignored by all of the
-Google Apps that use voice recognition..</p>
+the noise suppression pre-processing effect. It should not be turned on by default when recording from this audio source,
+and you should not enable it in your own audio_effects.conf file. Turning on the effect by default will cause the device to fail
+the <a href="http://static.googleusercontent.com/external_content/untrusted_dlcp/source.android.com/en/us/compatibility/4.2/android-4.2-cdd.pdf"> compatibility requirement </a>
+regardless of whether is was on by default due to configuration file, or the audio HAL implementation's default behavior.</p>
-The following example enables pre-processing for the VOIP <code>AudioSource</code> and Camcorder <code>AudioSource</code>.
-If you turn these on, then the app developer does not need to explicilty request
-to use these effects when they are requesting the particular <code>AudioSource</code>.
-</p>
+<p>The following example enables pre-processing for the VoIP <code>AudioSource</code> and Camcorder <code>AudioSource</code>.
+By declaring the <code>AudioSource</code> configuration in this manner, the framework will automatically request from the audio HAL the use of those effects</p>
<pre>
pre_processing {
@@ -325,13 +324,13 @@
<li>Effects / pre-processing must be disabled by default</li>
</ul>
-For other sources, you could tune sources with the following effects:
+<p>Examples of tuning different effects for different sources are:</p>
<ul>
- <li>Noise Supressor
+ <li>Noise Suppressor
<ul>
- <li>Tunes for wind noise supressor for <code>CAMCORDER</code></li>
- <li>Tuned for stationary noise supressor for <code>VOICE_COMMUNICATION</code></li>
+ <li>Tuned for wind noise suppressor for <code>CAMCORDER</code></li>
+ <li>Tuned for stationary noise suppressor for <code>VOICE_COMMUNICATION</code></li>
</ul>
</li>
<li>Automatic Gain Control