Merge "Update android.media.AudioTrack.getTimestamp API documentation"
diff --git a/media/java/android/media/AudioTrack.java b/media/java/android/media/AudioTrack.java
index 1baaaa4..8eb83e4 100644
--- a/media/java/android/media/AudioTrack.java
+++ b/media/java/android/media/AudioTrack.java
@@ -791,11 +791,17 @@
/**
* Poll for a timestamp on demand.
- *
- * Use if you need to get the most recent timestamp outside of the event callback handler.
- * Calling this method too often may be inefficient;
- * if you need a high-resolution mapping between frame position and presentation time,
+ * <p>
+ * If you need to track timestamps during initial warmup or after a routing or mode change,
+ * you should request a new timestamp once per second until the reported timestamps
+ * show that the audio clock is stable.
+ * Thereafter, query for a new timestamp approximately once every 10 seconds to once per minute.
+ * Calling this method more often is inefficient.
+ * It is also counter-productive to call this method more often than recommended,
+ * because the short-term differences between successive timestamp reports are not meaningful.
+ * If you need a high-resolution mapping between frame position and presentation time,
* consider implementing that at application level, based on low-resolution timestamps.
+ * <p>
* The audio data at the returned position may either already have been
* presented, or may have not yet been presented but is committed to be presented.
* It is not possible to request the time corresponding to a particular position,
@@ -811,6 +817,8 @@
* be presented.
* In the case that no timestamp is available, any supplied instance is left unaltered.
*/
+ // Add this text when the "on new timestamp" API is added:
+ // Use if you need to get the most recent timestamp outside of the event callback handler.
public boolean getTimestamp(AudioTimestamp timestamp)
{
if (timestamp == null) {