From 1c11febf3fa92ff6df7196510b19c7f6d717f062 Mon Sep 17 00:00:00 2001
From: olly <olly@google.com>
Date: Fri, 27 Mar 2020 18:01:16 +0000
Subject: [PATCH] Workaround C2 AAC decoder flush problem on Android 10

Issue: #6671
PiperOrigin-RevId: 303364788
---
 RELEASENOTES.md                               |  2 ++
 .../mediacodec/MediaCodecRenderer.java        | 24 +++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index 212f02f6fe6..b2ce5a4e883 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -67,6 +67,8 @@
         to the `DefaultAudioSink` constructor
         ([#7134](https://github.com/google/ExoPlayer/issues/7134)).
     *   Add media item based playlist API to Player.
+    *   Workaround issue that could cause slower than realtime playback of AAC
+        on Android 10 ([#6671](https://github.com/google/ExoPlayer/issues/6671).
 *   Text:
     *   Parse `<ruby>` and `<rt>` tags in WebVTT subtitles (rendering is coming
         later).
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecRenderer.java b/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecRenderer.java
index b5fe6de11a9..bb772a70255 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecRenderer.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecRenderer.java
@@ -386,6 +386,7 @@ private static String buildCustomDiagnosticInfo(int errorCode) {
   private boolean codecNeedsReconfigureWorkaround;
   private boolean codecNeedsDiscardToSpsWorkaround;
   private boolean codecNeedsFlushWorkaround;
+  private boolean codecNeedsSosFlushWorkaround;
   private boolean codecNeedsEosFlushWorkaround;
   private boolean codecNeedsEosOutputExceptionWorkaround;
   private boolean codecNeedsMonoChannelCountWorkaround;
@@ -406,6 +407,7 @@ private static String buildCustomDiagnosticInfo(int errorCode) {
   @DrainAction private int codecDrainAction;
   private boolean codecReceivedBuffers;
   private boolean codecReceivedEos;
+  private boolean codecHasOutputMediaFormat;
   private long largestQueuedPresentationTimeUs;
   private long lastBufferInStreamPresentationTimeUs;
   private boolean inputStreamEnded;
@@ -838,6 +840,7 @@ protected boolean flushOrReleaseCodec() {
     }
     if (codecDrainAction == DRAIN_ACTION_REINITIALIZE
         || codecNeedsFlushWorkaround
+        || (codecNeedsSosFlushWorkaround && !codecHasOutputMediaFormat)
         || (codecNeedsEosFlushWorkaround && codecReceivedEos)) {
       releaseCodec();
       return true;
@@ -889,11 +892,13 @@ protected void resetCodecStateForRelease() {
     availableCodecInfos = null;
     codecInfo = null;
     codecFormat = null;
+    codecHasOutputMediaFormat = false;
     codecOperatingRate = CODEC_OPERATING_RATE_UNSET;
     codecAdaptationWorkaroundMode = ADAPTATION_WORKAROUND_MODE_NEVER;
     codecNeedsReconfigureWorkaround = false;
     codecNeedsDiscardToSpsWorkaround = false;
     codecNeedsFlushWorkaround = false;
+    codecNeedsSosFlushWorkaround = false;
     codecNeedsEosFlushWorkaround = false;
     codecNeedsEosOutputExceptionWorkaround = false;
     codecNeedsMonoChannelCountWorkaround = false;
@@ -1084,6 +1089,7 @@ private void initCodec(MediaCodecInfo codecInfo, MediaCrypto crypto) throws Exce
     codecNeedsReconfigureWorkaround = codecNeedsReconfigureWorkaround(codecName);
     codecNeedsDiscardToSpsWorkaround = codecNeedsDiscardToSpsWorkaround(codecName, codecFormat);
     codecNeedsFlushWorkaround = codecNeedsFlushWorkaround(codecName);
+    codecNeedsSosFlushWorkaround = codecNeedsSosFlushWorkaround(codecName);
     codecNeedsEosFlushWorkaround = codecNeedsEosFlushWorkaround(codecName);
     codecNeedsEosOutputExceptionWorkaround = codecNeedsEosOutputExceptionWorkaround(codecName);
     codecNeedsMonoChannelCountWorkaround =
@@ -1738,6 +1744,7 @@ private boolean drainOutputBuffer(long positionUs, long elapsedRealtimeUs)
 
   /** Processes a new output {@link MediaFormat}. */
   private void processOutputMediaFormat() throws ExoPlaybackException {
+    codecHasOutputMediaFormat = true;
     MediaFormat mediaFormat = codecAdapter.getOutputFormat();
     if (codecAdaptationWorkaroundMode != ADAPTATION_WORKAROUND_MODE_NEVER
         && mediaFormat.getInteger(MediaFormat.KEY_WIDTH) == ADAPTATION_WORKAROUND_SLICE_WIDTH_HEIGHT
@@ -2139,4 +2146,21 @@ private static boolean codecNeedsMonoChannelCountWorkaround(String name, Format
     return Util.SDK_INT <= 18 && format.channelCount == 1
         && "OMX.MTK.AUDIO.DECODER.MP3".equals(name);
   }
+
+  /**
+   * Returns whether the decoder is known to behave incorrectly if flushed prior to having output a
+   * {@link MediaFormat}.
+   *
+   * <p>If true is returned, the renderer will work around the issue by instantiating a new decoder
+   * when this case occurs.
+   *
+   * <p>See [Internal: b/141097367].
+   *
+   * @param name The name of the decoder.
+   * @return True if the decoder is known to behave incorrectly if flushed prior to having output a
+   *     {@link MediaFormat}. False otherwise.
+   */
+  private static boolean codecNeedsSosFlushWorkaround(String name) {
+    return Util.SDK_INT == 29 && "c2.android.aac.decoder".equals(name);
+  }
 }