commit 187dcd4eeaeace78665dafcee6acb074ef390545
author Phil Burk <philburk@google.com> Tue Aug 29 09:04:35 2017 -0700
committer Phil Burk <philburk@google.com> Wed Sep 06 16:42:34 2017 -0700
tree 01ed91d32634e648d06b059da4f9dda126620a44
parent cda5c070b3188a52771aa463507312ecf0180976

aaudio example: print timestamps during callbacks.

Bug: 63918065
Test: this is a test
Change-Id: Id25dd36764761583986d3ce29f7d82032ec4539f

media/libaaudio/examples/utils/AAudioSimplePlayer.h

diff --git a/media/libaaudio/examples/utils/AAudioSimplePlayer.h b/media/libaaudio/examples/utils/AAudioSimplePlayer.h
index d2e7f23..606c4ba 100644
--- a/media/libaaudio/examples/utils/AAudioSimplePlayer.h
+++ b/media/libaaudio/examples/utils/AAudioSimplePlayer.h
@@ -36,6 +36,13 @@
 // How long to sleep in a callback to cause an intentional glitch. For testing.
 #define FORCED_UNDERRUN_SLEEP_MICROS     (10 * 1000)
 
+#define MAX_TIMESTAMPS   16
+
+typedef struct Timestamp {
+    int64_t position;
+    int64_t nanoseconds;
+} Timestamp;
+
 /**
  * Simple wrapper for AAudio that opens an output stream either in callback or blocking write mode.
  */
@@ -227,10 +234,12 @@
 
     SineGenerator  sineOsc1;
     SineGenerator  sineOsc2;
+    Timestamp      timestamps[MAX_TIMESTAMPS];
     int64_t        framesTotal = 0;
     int64_t        nextFrameToGlitch = FORCED_UNDERRUN_PERIOD_FRAMES;
     int32_t        minNumFrames = INT32_MAX;
     int32_t        maxNumFrames = 0;
+    int32_t        timestampCount = 0; // in timestamps
 
     int            scheduler = 0;
     bool           schedulerChecked = false;
@@ -273,6 +282,17 @@
         sineData->schedulerChecked = true;
     }
 
+    if (sineData->timestampCount < MAX_TIMESTAMPS) {
+        Timestamp *timestamp = &sineData->timestamps[sineData->timestampCount];
+        aaudio_result_t result = AAudioStream_getTimestamp(stream,
+            CLOCK_MONOTONIC, &timestamp->position, &timestamp->nanoseconds);
+        if (result == AAUDIO_OK && // valid?
+                (sineData->timestampCount == 0 || // first one?
+                (timestamp->position != (timestamp - 1)->position))) { // advanced position?
+            sineData->timestampCount++; // keep this one
+        }
+    }
+
     if (numFrames > sineData->maxNumFrames) {
         sineData->maxNumFrames = numFrames;
     }

media/libaaudio/examples/write_sine/src/write_sine_callback.cpp

diff --git a/media/libaaudio/examples/write_sine/src/write_sine_callback.cpp b/media/libaaudio/examples/write_sine/src/write_sine_callback.cpp
index 2280b72..4f9cde6 100644
--- a/media/libaaudio/examples/write_sine/src/write_sine_callback.cpp
+++ b/media/libaaudio/examples/write_sine/src/write_sine_callback.cpp
@@ -120,6 +120,18 @@
         goto error;
     }
 
+    for (int i = 0; i < myData.timestampCount; i++) {
+        Timestamp *timestamp = &myData.timestamps[i];
+        bool retro = (i > 0 &&
+                      ((timestamp->position < (timestamp - 1)->position)
+                       || ((timestamp->nanoseconds < (timestamp - 1)->nanoseconds))));
+        const char *message = retro ? "  <= RETROGRADE!" : "";
+        printf("Timestamp %3d : %8lld, %8lld %s\n", i,
+               (long long) timestamp->position,
+               (long long) timestamp->nanoseconds,
+               message);
+    }
+
     if (myData.schedulerChecked) {
         printf("scheduler = 0x%08x, SCHED_FIFO = 0x%08X\n",
                myData.scheduler,