Handle input format changes in SimpleDecoderAudioRenderer.

This is implemented in the same way as in MediaCodecRenderer.

Move codec != null guard into feedInputBuffer to handle the case of an input
format change with no dequeued buffers where the codec can't be reinitialized
immediately.

Issue: #2111

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=140864942

library/src/main/java/com/google/android/exoplayer2/audio/SimpleDecoderAudioRenderer.java

@@ -19,6 +19,7 @@ import android.media.PlaybackParams;
 import android.os.Handler;
 import android.os.Handler;
 import android.os.Looper;
 import android.os.Looper;
 import android.os.SystemClock;
 import android.os.SystemClock;
+import android.support.annotation.IntDef;
 import com.google.android.exoplayer2.BaseRenderer;
 import com.google.android.exoplayer2.BaseRenderer;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.ExoPlaybackException;
 import com.google.android.exoplayer2.ExoPlaybackException;
@@ -36,6 +37,8 @@ import com.google.android.exoplayer2.util.MediaClock;
 import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.TraceUtil;
 import com.google.android.exoplayer2.util.TraceUtil;
 import com.google.android.exoplayer2.util.Util;
 import com.google.android.exoplayer2.util.Util;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
 
 
 /**
 /**
  * Decodes and renders audio using a {@link SimpleDecoder}.
  * Decodes and renders audio using a {@link SimpleDecoder}.
@@ -43,6 +46,27 @@ import com.google.android.exoplayer2.util.Util;
 public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements MediaClock,
 public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements MediaClock,
     AudioTrack.Listener {
     AudioTrack.Listener {
 
 
+  @Retention(RetentionPolicy.SOURCE)
+  @IntDef({REINITIALIZATION_STATE_NONE, REINITIALIZATION_STATE_SIGNAL_END_OF_STREAM,
+      REINITIALIZATION_STATE_WAIT_END_OF_STREAM})
+  private @interface ReinitializationState {}
+  /**
+   * The decoder does not need to be re-initialized.
+   */
+  private static final int REINITIALIZATION_STATE_NONE = 0;
+  /**
+   * The input format has changed in a way that requires the decoder to be re-initialized, but we
+   * haven't yet signaled an end of stream to the existing decoder. We need to do so in order to
+   * ensure that it outputs any remaining buffers before we release it.
+   */
+  private static final int REINITIALIZATION_STATE_SIGNAL_END_OF_STREAM = 1;
+  /**
+   * The input format has changed in a way that requires the decoder to be re-initialized, and we've
+   * signaled an end of stream to the existing decoder. We're waiting for the decoder to output an
+   * end of stream signal to indicate that it has output any remaining buffers before we release it.
+   */
+  private static final int REINITIALIZATION_STATE_WAIT_END_OF_STREAM = 2;
+
   private final boolean playClearSamplesWithoutKeys;
   private final boolean playClearSamplesWithoutKeys;
 
 
   private final EventDispatcher eventDispatcher;
   private final EventDispatcher eventDispatcher;
@@ -59,6 +83,11 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
   private DrmSession<ExoMediaCrypto> drmSession;
   private DrmSession<ExoMediaCrypto> drmSession;
   private DrmSession<ExoMediaCrypto> pendingDrmSession;
   private DrmSession<ExoMediaCrypto> pendingDrmSession;
 
 
+  @ReinitializationState
+  private int decoderReinitializationState;
+  private boolean decoderReceivedBuffers;
+  private boolean audioTrackNeedsConfigure;
+
   private long currentPositionUs;
   private long currentPositionUs;
   private boolean allowPositionDiscontinuity;
   private boolean allowPositionDiscontinuity;
   private boolean inputStreamEnded;
   private boolean inputStreamEnded;
@@ -117,6 +146,8 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
     formatHolder = new FormatHolder();
     formatHolder = new FormatHolder();
     this.playClearSamplesWithoutKeys = playClearSamplesWithoutKeys;
     this.playClearSamplesWithoutKeys = playClearSamplesWithoutKeys;
     audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
     audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+    decoderReinitializationState = REINITIALIZATION_STATE_NONE;
+    audioTrackNeedsConfigure = true;
   }
   }
 
 
   @Override
   @Override
@@ -136,38 +167,12 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
       return;
       return;
     }
     }
 
 
-    drmSession = pendingDrmSession;
-    ExoMediaCrypto mediaCrypto = null;
-    if (drmSession != null) {
-      @DrmSession.State int drmSessionState = drmSession.getState();
-      if (drmSessionState == DrmSession.STATE_ERROR) {
-        throw ExoPlaybackException.createForRenderer(drmSession.getError(), getIndex());
-      } else if (drmSessionState == DrmSession.STATE_OPENED
-          || drmSessionState == DrmSession.STATE_OPENED_WITH_KEYS) {
-        mediaCrypto = drmSession.getMediaCrypto();
-      } else {
-        // The drm session isn't open yet.
-        return;
-      }
-    }
     // If we don't have a decoder yet, we need to instantiate one.
     // If we don't have a decoder yet, we need to instantiate one.
-    if (decoder == null) {
-      try {
-        long codecInitializingTimestamp = SystemClock.elapsedRealtime();
-        TraceUtil.beginSection("createAudioDecoder");
-        decoder = createDecoder(inputFormat, mediaCrypto);
-        TraceUtil.endSection();
-        long codecInitializedTimestamp = SystemClock.elapsedRealtime();
-        eventDispatcher.decoderInitialized(decoder.getName(), codecInitializedTimestamp,
-            codecInitializedTimestamp - codecInitializingTimestamp);
-        decoderCounters.decoderInitCount++;
-      } catch (AudioDecoderException e) {
-        throw ExoPlaybackException.createForRenderer(e, getIndex());
-      }
-    }
+    maybeInitDecoder();
 
 
-    // Rendering loop.
+    if (decoder != null) {
       try {
       try {
+        // Rendering loop.
         TraceUtil.beginSection("drainAndFeed");
         TraceUtil.beginSection("drainAndFeed");
         while (drainOutputBuffer()) {}
         while (drainOutputBuffer()) {}
         while (feedInputBuffer()) {}
         while (feedInputBuffer()) {}
@@ -178,6 +183,7 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
       }
       }
       decoderCounters.ensureUpdated();
       decoderCounters.ensureUpdated();
     }
     }
+  }
 
 
   /**
   /**
    * Creates a decoder for the given format.
    * Creates a decoder for the given format.
@@ -205,12 +211,8 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
         null, null, 0, null);
         null, null, 0, null);
   }
   }
 
 
-  private boolean drainOutputBuffer() throws AudioDecoderException,
+  private boolean drainOutputBuffer() throws ExoPlaybackException, AudioDecoderException,
       AudioTrack.InitializationException, AudioTrack.WriteException {
       AudioTrack.InitializationException, AudioTrack.WriteException {
-    if (outputStreamEnded) {
-      return false;
-    }
-
     if (outputBuffer == null) {
     if (outputBuffer == null) {
       outputBuffer = decoder.dequeueOutputBuffer();
       outputBuffer = decoder.dequeueOutputBuffer();
       if (outputBuffer == null) {
       if (outputBuffer == null) {
@@ -220,17 +222,29 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
     }
     }
 
 
     if (outputBuffer.isEndOfStream()) {
     if (outputBuffer.isEndOfStream()) {
-      outputStreamEnded = true;
-      audioTrack.handleEndOfStream();
+      if (decoderReinitializationState == REINITIALIZATION_STATE_WAIT_END_OF_STREAM) {
+        // We're waiting to re-initialize the decoder, and have now processed all final buffers.
+        releaseDecoder();
+        maybeInitDecoder();
+        // The audio track may need to be recreated once the new output format is known.
+        audioTrackNeedsConfigure = true;
+      } else {
         outputBuffer.release();
         outputBuffer.release();
         outputBuffer = null;
         outputBuffer = null;
+        outputStreamEnded = true;
+        audioTrack.handleEndOfStream();
+      }
       return false;
       return false;
     }
     }
 
 
-    if (!audioTrack.isInitialized()) {
+    if (audioTrackNeedsConfigure) {
       Format outputFormat = getOutputFormat();
       Format outputFormat = getOutputFormat();
       audioTrack.configure(outputFormat.sampleMimeType, outputFormat.channelCount,
       audioTrack.configure(outputFormat.sampleMimeType, outputFormat.channelCount,
           outputFormat.sampleRate, outputFormat.pcmEncoding, 0);
           outputFormat.sampleRate, outputFormat.pcmEncoding, 0);
+      audioTrackNeedsConfigure = false;
+    }
+
+    if (!audioTrack.isInitialized()) {
       if (audioSessionId == AudioTrack.SESSION_ID_NOT_SET) {
       if (audioSessionId == AudioTrack.SESSION_ID_NOT_SET) {
         audioSessionId = audioTrack.initialize(AudioTrack.SESSION_ID_NOT_SET);
         audioSessionId = audioTrack.initialize(AudioTrack.SESSION_ID_NOT_SET);
         eventDispatcher.audioSessionId(audioSessionId);
         eventDispatcher.audioSessionId(audioSessionId);
@@ -262,7 +276,9 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
   }
   }
 
 
   private boolean feedInputBuffer() throws AudioDecoderException, ExoPlaybackException {
   private boolean feedInputBuffer() throws AudioDecoderException, ExoPlaybackException {
-    if (inputStreamEnded) {
+    if (decoder == null || decoderReinitializationState == REINITIALIZATION_STATE_WAIT_END_OF_STREAM
+        || inputStreamEnded) {
+      // We need to reinitialize the decoder or the input stream has ended.
       return false;
       return false;
     }
     }
 
 
@@ -273,6 +289,14 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
       }
       }
     }
     }
 
 
+    if (decoderReinitializationState == REINITIALIZATION_STATE_SIGNAL_END_OF_STREAM) {
+      inputBuffer.setFlags(C.BUFFER_FLAG_END_OF_STREAM);
+      decoder.queueInputBuffer(inputBuffer);
+      inputBuffer = null;
+      decoderReinitializationState = REINITIALIZATION_STATE_WAIT_END_OF_STREAM;
+      return false;
+    }
+
     int result;
     int result;
     if (waitingForKeys) {
     if (waitingForKeys) {
       // We've already read an encrypted sample into buffer, and are waiting for keys.
       // We've already read an encrypted sample into buffer, and are waiting for keys.
@@ -301,6 +325,7 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
     }
     }
     inputBuffer.flip();
     inputBuffer.flip();
     decoder.queueInputBuffer(inputBuffer);
     decoder.queueInputBuffer(inputBuffer);
+    decoderReceivedBuffers = true;
     decoderCounters.inputBufferCount++;
     decoderCounters.inputBufferCount++;
     inputBuffer = null;
     inputBuffer = null;
     return true;
     return true;
@@ -318,14 +343,20 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
         && (bufferEncrypted || !playClearSamplesWithoutKeys);
         && (bufferEncrypted || !playClearSamplesWithoutKeys);
   }
   }
 
 
-  private void flushDecoder() {
-    inputBuffer = null;
+  private void flushDecoder() throws ExoPlaybackException {
     waitingForKeys = false;
     waitingForKeys = false;
+    if (decoderReinitializationState != REINITIALIZATION_STATE_NONE) {
+      releaseDecoder();
+      maybeInitDecoder();
+    } else {
+      inputBuffer = null;
       if (outputBuffer != null) {
       if (outputBuffer != null) {
         outputBuffer.release();
         outputBuffer.release();
         outputBuffer = null;
         outputBuffer = null;
       }
       }
       decoder.flush();
       decoder.flush();
+      decoderReceivedBuffers = false;
+    }
   }
   }
 
 
   @Override
   @Override
@@ -370,7 +401,7 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
   }
   }
 
 
   @Override
   @Override
-  protected void onPositionReset(long positionUs, boolean joining) {
+  protected void onPositionReset(long positionUs, boolean joining) throws ExoPlaybackException {
     audioTrack.reset();
     audioTrack.reset();
     currentPositionUs = positionUs;
     currentPositionUs = positionUs;
     allowPositionDiscontinuity = true;
     allowPositionDiscontinuity = true;
@@ -393,17 +424,12 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
 
 
   @Override
   @Override
   protected void onDisabled() {
   protected void onDisabled() {
-    inputBuffer = null;
-    outputBuffer = null;
     inputFormat = null;
     inputFormat = null;
     audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
     audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+    audioTrackNeedsConfigure = true;
     waitingForKeys = false;
     waitingForKeys = false;
     try {
     try {
-      if (decoder != null) {
-        decoder.release();
-        decoder = null;
-        decoderCounters.decoderReleaseCount++;
-      }
+      releaseDecoder();
       audioTrack.release();
       audioTrack.release();
     } finally {
     } finally {
       try {
       try {
@@ -425,6 +451,54 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
     }
     }
   }
   }
 
 
+  private void maybeInitDecoder() throws ExoPlaybackException {
+    if (decoder != null) {
+      return;
+    }
+
+    drmSession = pendingDrmSession;
+    ExoMediaCrypto mediaCrypto = null;
+    if (drmSession != null) {
+      @DrmSession.State int drmSessionState = drmSession.getState();
+      if (drmSessionState == DrmSession.STATE_ERROR) {
+        throw ExoPlaybackException.createForRenderer(drmSession.getError(), getIndex());
+      } else if (drmSessionState == DrmSession.STATE_OPENED
+          || drmSessionState == DrmSession.STATE_OPENED_WITH_KEYS) {
+        mediaCrypto = drmSession.getMediaCrypto();
+      } else {
+        // The drm session isn't open yet.
+        return;
+      }
+    }
+
+    try {
+      long codecInitializingTimestamp = SystemClock.elapsedRealtime();
+      TraceUtil.beginSection("createAudioDecoder");
+      decoder = createDecoder(inputFormat, mediaCrypto);
+      TraceUtil.endSection();
+      long codecInitializedTimestamp = SystemClock.elapsedRealtime();
+      eventDispatcher.decoderInitialized(decoder.getName(), codecInitializedTimestamp,
+          codecInitializedTimestamp - codecInitializingTimestamp);
+      decoderCounters.decoderInitCount++;
+    } catch (AudioDecoderException e) {
+      throw ExoPlaybackException.createForRenderer(e, getIndex());
+    }
+  }
+
+  private void releaseDecoder() {
+    if (decoder == null) {
+      return;
+    }
+
+    inputBuffer = null;
+    outputBuffer = null;
+    decoder.release();
+    decoder = null;
+    decoderCounters.decoderReleaseCount++;
+    decoderReinitializationState = REINITIALIZATION_STATE_NONE;
+    decoderReceivedBuffers = false;
+  }
+
   private boolean readFormat() throws ExoPlaybackException {
   private boolean readFormat() throws ExoPlaybackException {
     int result = readSource(formatHolder, null);
     int result = readSource(formatHolder, null);
     if (result == C.RESULT_FORMAT_READ) {
     if (result == C.RESULT_FORMAT_READ) {
@@ -456,6 +530,15 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
       }
       }
     }
     }
 
 
+    if (decoderReceivedBuffers) {
+      // Signal end of stream and wait for any final output buffers before re-initialization.
+      decoderReinitializationState = REINITIALIZATION_STATE_SIGNAL_END_OF_STREAM;
+    } else {
+      // There aren't any final output buffers, so release the decoder immediately.
+      releaseDecoder();
+      maybeInitDecoder();
+    }
+
     eventDispatcher.inputFormatChanged(newFormat);
     eventDispatcher.inputFormatChanged(newFormat);
   }
   }
 
 

library/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecRenderer.java

@@ -472,6 +472,9 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
 
 
   @Override
   @Override
   public void render(long positionUs, long elapsedRealtimeUs) throws ExoPlaybackException {
   public void render(long positionUs, long elapsedRealtimeUs) throws ExoPlaybackException {
+    if (outputStreamEnded) {
+      return;
+    }
     if (format == null) {
     if (format == null) {
       readFormat();
       readFormat();
     }
     }
@@ -479,9 +482,7 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
     if (codec != null) {
     if (codec != null) {
       TraceUtil.beginSection("drainAndFeed");
       TraceUtil.beginSection("drainAndFeed");
       while (drainOutputBuffer(positionUs, elapsedRealtimeUs)) {}
       while (drainOutputBuffer(positionUs, elapsedRealtimeUs)) {}
-      if (codec != null) {
       while (feedInputBuffer()) {}
       while (feedInputBuffer()) {}
-      }
       TraceUtil.endSection();
       TraceUtil.endSection();
     } else if (format != null) {
     } else if (format != null) {
       skipToKeyframeBefore(positionUs);
       skipToKeyframeBefore(positionUs);
@@ -531,10 +532,9 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
    * @throws ExoPlaybackException If an error occurs feeding the input buffer.
    * @throws ExoPlaybackException If an error occurs feeding the input buffer.
    */
    */
   private boolean feedInputBuffer() throws ExoPlaybackException {
   private boolean feedInputBuffer() throws ExoPlaybackException {
-    if (inputStreamEnded
-        || codecReinitializationState == REINITIALIZATION_STATE_WAIT_END_OF_STREAM) {
-      // The input stream has ended, or we need to re-initialize the codec but are still waiting
-      // for the existing codec to output any final output buffers.
+    if (codec == null || codecReinitializationState == REINITIALIZATION_STATE_WAIT_END_OF_STREAM
+        || inputStreamEnded) {
+      // We need to reinitialize the codec or the input stream has ended.
       return false;
       return false;
     }
     }
 
 
@@ -848,10 +848,6 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
   @SuppressWarnings("deprecation")
   @SuppressWarnings("deprecation")
   private boolean drainOutputBuffer(long positionUs, long elapsedRealtimeUs)
   private boolean drainOutputBuffer(long positionUs, long elapsedRealtimeUs)
       throws ExoPlaybackException {
       throws ExoPlaybackException {
-    if (outputStreamEnded) {
-      return false;
-    }
-
     if (outputIndex < 0) {
     if (outputIndex < 0) {
       outputIndex = codec.dequeueOutputBuffer(outputBufferInfo, getDequeueOutputBufferTimeoutUs());
       outputIndex = codec.dequeueOutputBuffer(outputBufferInfo, getDequeueOutputBufferTimeoutUs());
       if (outputIndex >= 0) {
       if (outputIndex >= 0) {