Start playing (and decoding) audio only after the first video frame has been decoded.

if there's both audio and video content. This gives the video decoder an opportunity
to fill its internal buffer queue at the start of playback.

Change-Id: Ib2c95753b430e4e47207953b913b607024a328d7
related-to-bug: 3431702
diff --git a/media/libstagefright/AwesomePlayer.cpp b/media/libstagefright/AwesomePlayer.cpp
index 8963951..e368848 100644
--- a/media/libstagefright/AwesomePlayer.cpp
+++ b/media/libstagefright/AwesomePlayer.cpp
@@ -794,25 +794,6 @@
                 mAudioPlayer = new AudioPlayer(mAudioSink, this);
                 mAudioPlayer->setSource(mAudioSource);
 
-                // We've already started the MediaSource in order to enable
-                // the prefetcher to read its data.
-                status_t err = mAudioPlayer->start(
-                        true /* sourceAlreadyStarted */);
-
-                if (err != OK) {
-                    delete mAudioPlayer;
-                    mAudioPlayer = NULL;
-
-                    mFlags &= ~(PLAYING | FIRST_FRAME);
-
-                    if (mDecryptHandle != NULL) {
-                        mDrmManagerClient->setPlaybackStatus(mDecryptHandle,
-                                 Playback::STOP, 0);
-                    }
-
-                    return err;
-                }
-
                 mTimeSource = mAudioPlayer;
 
                 deferredAudioSeek = true;
@@ -820,8 +801,26 @@
                 mWatchForAudioSeekComplete = false;
                 mWatchForAudioEOS = true;
             }
-        } else {
-            mAudioPlayer->resume();
+        }
+
+        CHECK(!(mFlags & AUDIO_RUNNING));
+
+        if (mVideoSource == NULL) {
+            status_t err = startAudioPlayer_l();
+
+            if (err != OK) {
+                delete mAudioPlayer;
+                mAudioPlayer = NULL;
+
+                mFlags &= ~(PLAYING | FIRST_FRAME);
+
+                if (mDecryptHandle != NULL) {
+                    mDrmManagerClient->setPlaybackStatus(
+                            mDecryptHandle, Playback::STOP, 0);
+                }
+
+                return err;
+            }
         }
     }
 
@@ -853,6 +852,36 @@
     return OK;
 }
 
+status_t AwesomePlayer::startAudioPlayer_l() {
+    CHECK(!(mFlags & AUDIO_RUNNING));
+
+    if (mAudioSource == NULL || mAudioPlayer == NULL) {
+        return OK;
+    }
+
+    if (!(mFlags & AUDIOPLAYER_STARTED)) {
+        mFlags |= AUDIOPLAYER_STARTED;
+
+        // We've already started the MediaSource in order to enable
+        // the prefetcher to read its data.
+        status_t err = mAudioPlayer->start(
+                true /* sourceAlreadyStarted */);
+
+        if (err != OK) {
+            notifyListener_l(MEDIA_ERROR, MEDIA_ERROR_UNKNOWN, err);
+            return err;
+        }
+    } else {
+        mAudioPlayer->resume();
+    }
+
+    mFlags |= AUDIO_RUNNING;
+
+    mWatchForAudioEOS = true;
+
+    return OK;
+}
+
 void AwesomePlayer::notifyVideoSize_l() {
     sp<MetaData> meta = mVideoSource->getFormat();
 
@@ -954,7 +983,7 @@
 
     cancelPlayerEvents(true /* keepBufferingGoing */);
 
-    if (mAudioPlayer != NULL) {
+    if (mAudioPlayer != NULL && (mFlags & AUDIO_RUNNING)) {
         if (at_eos) {
             // If we played the audio stream to completion we
             // want to make sure that all samples remaining in the audio
@@ -963,6 +992,8 @@
         } else {
             mAudioPlayer->pause();
         }
+
+        mFlags &= ~AUDIO_RUNNING;
     }
 
     mFlags &= ~PLAYING;
@@ -1195,9 +1226,7 @@
         // requested seek time instead.
 
         mAudioPlayer->seekTo(videoTimeUs < 0 ? mSeekTimeUs : videoTimeUs);
-        mAudioPlayer->resume();
         mWatchForAudioSeekComplete = true;
-        mWatchForAudioEOS = true;
     } else if (!mSeekNotificationSent) {
         // If we're playing video only, report seek complete now,
         // otherwise audio player will notify us later.
@@ -1241,8 +1270,10 @@
             // locations, we'll "pause" the audio source, causing it to
             // stop reading input data until a subsequent seek.
 
-            if (mAudioPlayer != NULL) {
+            if (mAudioPlayer != NULL && (mFlags & AUDIO_RUNNING)) {
                 mAudioPlayer->pause();
+
+                mFlags &= ~AUDIO_RUNNING;
             }
             mAudioSource->pause();
         }
@@ -1312,6 +1343,14 @@
     bool wasSeeking = mSeeking;
     finishSeekIfNecessary(timeUs);
 
+    if (mAudioPlayer != NULL && !(mFlags & (AUDIO_RUNNING | SEEK_PREVIEW))) {
+        status_t err = startAudioPlayer_l();
+        if (err != OK) {
+            LOGE("Startung the audio player failed w/ err %d", err);
+            return;
+        }
+    }
+
     TimeSource *ts = (mFlags & AUDIO_AT_EOS) ? &mSystemTimeSource : mTimeSource;
 
     if (mFlags & FIRST_FRAME) {
diff --git a/media/libstagefright/include/AwesomePlayer.h b/media/libstagefright/include/AwesomePlayer.h
index 5120a12..797e5ca 100644
--- a/media/libstagefright/include/AwesomePlayer.h
+++ b/media/libstagefright/include/AwesomePlayer.h
@@ -121,6 +121,9 @@
         // We're triggering a single video event to display the first frame
         // after the seekpoint.
         SEEK_PREVIEW        = 4096,
+
+        AUDIO_RUNNING       = 8192,
+        AUDIOPLAYER_STARTED = 16384,
     };
 
     mutable Mutex mLock;
@@ -256,6 +259,8 @@
     void finishSeekIfNecessary(int64_t videoTimeUs);
     void ensureCacheIsFetching_l();
 
+    status_t startAudioPlayer_l();
+
     AwesomePlayer(const AwesomePlayer &);
     AwesomePlayer &operator=(const AwesomePlayer &);
 };