commit 97350f9df7252c881f011a410fcd9e6d766d2bee
author Phil Burk <philburk@google.com> Fri Jul 21 15:59:44 2017 -0700
committer Phil Burk <philburk@google.com> Wed Aug 02 10:57:31 2017 -0700
tree fab6334a25607e03276648611584b8fc23b40463
parent eb1c0658e405e5b7e26f4b16761c5b1ce3f77d46

aaudio: improve accuracy of timestamps

Account for latency added by the AAudio service.
Fix input timestamps.

Bug: 37080396
Test: test_timestamps.cpp input_monitor.cpp
Change-Id: I1053cd21af722bb9b9371df4e5731bf4a0a57b0b

services/oboeservice/AAudioServiceStreamShared.h

diff --git a/services/oboeservice/AAudioServiceStreamShared.h b/services/oboeservice/AAudioServiceStreamShared.h
index 6b67337..8caccda 100644
--- a/services/oboeservice/AAudioServiceStreamShared.h
+++ b/services/oboeservice/AAudioServiceStreamShared.h
@@ -85,7 +85,11 @@
     /* Keep a record of when a buffer transfer completed.
      * This allows for a more accurate timing model.
      */
-    void markTransferTime(int64_t nanoseconds);
+    void markTransferTime(Timestamp &timestamp);
+
+    void setTimestampPositionOffset(int64_t deltaFrames) {
+        mTimestampPositionOffset.store(deltaFrames);
+    }
 
 protected:
 
@@ -93,6 +97,9 @@
 
     aaudio_result_t getFreeRunningPosition(int64_t *positionFrames, int64_t *timeNanos) override;
 
+    virtual aaudio_result_t getHardwareTimestamp(int64_t *positionFrames,
+                                                 int64_t *timeNanos) override;
+
     /**
      * @param requestedCapacityFrames
      * @param framesPerBurst
@@ -106,8 +113,7 @@
     AAudioServiceEndpoint   *mServiceEndpoint = nullptr;
     SharedRingBuffer        *mAudioDataQueue = nullptr;
 
-    int64_t                  mMarkedPosition = 0;
-    int64_t                  mMarkedTime = 0;
+    std::atomic<int64_t>     mTimestampPositionOffset;
 };
 
 } /* namespace aaudio */