Revert "Improving handling of atoms with size less than header in FragmentedMp4Extractor."

This reverts commit 71186ef16ee2f3dc07a4f9d1d696c273b1c6ca87.

RELEASENOTES.md

@@ -1,9 +1,19 @@
 # Release notes #
 
-### r2.1.0 ###
+### r2.1.1 ###
 
-This release contains important bug fixes. Users of r2.0.x should proactively
-update to this version.
+Bugfix release only. Users of r2.1.0 and r2.0.x should proactively update to
+this version.
+
+* Fix some subtitle types (e.g. WebVTT) being displayed out of sync
+  ([#2208](https://github.com/google/ExoPlayer/issues/2208)).
+* Fix incorrect position reporting for on-demand HLS media that includes
+  EXT-X-PROGRAM-DATE-TIME tags
+  ([#2224](https://github.com/google/ExoPlayer/issues/2224)).
+* Fix issue where playbacks could get stuck in the initial buffering state if
+  over 1MB of data needs to be read to initialize the playback.
+
+### r2.1.0 ###
 
 * HLS: Support for seeking in live streams
   ([#87](https://github.com/google/ExoPlayer/issues/87)).

build.gradle

@@ -35,7 +35,7 @@ allprojects {
         releaseRepoName = 'exoplayer'
         releaseUserOrg = 'google'
         releaseGroupId = 'com.google.android.exoplayer'
-        releaseVersion = 'r2.1.0'
+        releaseVersion = 'r2.1.1'
         releaseWebsite = 'https://github.com/google/ExoPlayer'
     }
 }

demo/src/main/AndroidManifest.xml

@@ -16,8 +16,8 @@
 
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.google.android.exoplayer2.demo"
-    android:versionCode="2100"
-    android:versionName="2.1.0">
+    android:versionCode="2101"
+    android:versionName="2.1.1">
 
   <uses-permission android:name="android.permission.INTERNET"/>
   <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

demo/src/main/assets/media.exolist.json

@@ -183,29 +183,53 @@
         "uri": "https://storage.googleapis.com/wvmedia/clear/vp9/tears/tears_uhd.mpd"
       },
       {
-        "name": "WV: Secure SD & HD (WebM,VP9)",
+        "name": "WV: Secure Fullsample SD & HD (WebM,VP9)",
         "uri": "https://storage.googleapis.com/wvmedia/cenc/vp9/tears/tears.mpd",
         "drm_scheme": "widevine",
         "drm_license_url": "https://proxy.uat.widevine.com/proxy?provider=widevine_test"
       },
       {
-        "name": "WV: Secure SD (WebM,VP9)",
+        "name": "WV: Secure Fullsample SD (WebM,VP9)",
         "uri": "https://storage.googleapis.com/wvmedia/cenc/vp9/tears/tears_sd.mpd",
         "drm_scheme": "widevine",
         "drm_license_url": "https://proxy.uat.widevine.com/proxy?provider=widevine_test"
       },
       {
-        "name": "WV: Secure HD (WebM,VP9)",
+        "name": "WV: Secure Fullsample HD (WebM,VP9)",
         "uri": "https://storage.googleapis.com/wvmedia/cenc/vp9/tears/tears_hd.mpd",
         "drm_scheme": "widevine",
         "drm_license_url": "https://proxy.uat.widevine.com/proxy?provider=widevine_test"
       },
       {
-        "name": "WV: Secure UHD (WebM,VP9)",
+        "name": "WV: Secure Fullsample UHD (WebM,VP9)",
         "uri": "https://storage.googleapis.com/wvmedia/cenc/vp9/tears/tears_uhd.mpd",
         "drm_scheme": "widevine",
         "drm_license_url": "https://proxy.uat.widevine.com/proxy?provider=widevine_test"
       },
+      {
+        "name": "WV: Secure Subsample SD & HD (WebM,VP9)",
+        "uri": "https://storage.googleapis.com/wvmedia/cenc/vp9/subsample/24fps/tears/tears.mpd",
+        "drm_scheme": "widevine",
+        "drm_license_url": "https://proxy.uat.widevine.com/proxy?provider=widevine_test"
+      },
+      {
+        "name": "WV: Secure Subsample SD (WebM,VP9)",
+        "uri": "https://storage.googleapis.com/wvmedia/cenc/vp9/subsample/24fps/tears/tears_sd.mpd",
+        "drm_scheme": "widevine",
+        "drm_license_url": "https://proxy.uat.widevine.com/proxy?provider=widevine_test"
+      },
+      {
+        "name": "WV: Secure Subsample HD (WebM,VP9)",
+        "uri": "https://storage.googleapis.com/wvmedia/cenc/vp9/subsample/24fps/tears/tears_hd.mpd",
+        "drm_scheme": "widevine",
+        "drm_license_url": "https://proxy.uat.widevine.com/proxy?provider=widevine_test"
+      },
+      {
+        "name": "WV: Secure Subsample UHD (WebM,VP9)",
+        "uri": "https://storage.googleapis.com/wvmedia/cenc/vp9/subsample/24fps/tears/tears_uhd.mpd",
+        "drm_scheme": "widevine",
+        "drm_license_url": "https://proxy.uat.widevine.com/proxy?provider=widevine_test"
+      },
       {
         "name": "WV: Secure Subsample (WebM, VP9 with altref)",
         "uri": "https://storage.googleapis.com/widevine_test/vp9/sintel_1080p_vp9_altref_subsample/sintel_1080p_vp9_altref_subsample.mpd",

library/src/androidTest/java/com/google/android/exoplayer2/ExoPlayerTest.java

@@ -31,6 +31,7 @@ import com.google.android.exoplayer2.upstream.Allocator;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.MimeTypes;
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
@@ -48,12 +49,25 @@ public final class ExoPlayerTest extends TestCase {
    */
   private static final int TIMEOUT_MS = 10000;
 
+  /**
+   * Tests playback of a source that exposes a single period.
+   */
   public void testPlayToEnd() throws Exception {
     PlayerWrapper playerWrapper = new PlayerWrapper();
     Format format = Format.createVideoSampleFormat(null, MimeTypes.VIDEO_H264, null,
         Format.NO_VALUE, Format.NO_VALUE, 1280, 720, Format.NO_VALUE, null, null);
-    playerWrapper.setup(new SinglePeriodTimeline(0, false), new Object(), format);
-    playerWrapper.blockUntilEndedOrError(TIMEOUT_MS);
+    playerWrapper.setup(new SinglePeriodTimeline(0, false), null, format);
+    playerWrapper.blockUntilEnded(TIMEOUT_MS);
+  }
+
+  /**
+   * Tests playback of a source that exposes an empty timeline. Playback is expected to end without
+   * error.
+   */
+  public void testPlayEmptyTimeline() throws Exception {
+    PlayerWrapper playerWrapper = new PlayerWrapper();
+    playerWrapper.setup(Timeline.EMPTY, null, null);
+    playerWrapper.blockUntilEnded(TIMEOUT_MS);
   }
 
   /**
@@ -70,7 +84,6 @@ public final class ExoPlayerTest extends TestCase {
     private Format expectedFormat;
     private ExoPlayer player;
     private Exception exception;
-    private boolean seenPositionDiscontinuity;
 
     public PlayerWrapper() {
       endedCountDownLatch = new CountDownLatch(1);
@@ -81,12 +94,11 @@ public final class ExoPlayerTest extends TestCase {
 
     // Called on the test thread.
 
-    public void blockUntilEndedOrError(long timeoutMs) throws Exception {
+    public void blockUntilEnded(long timeoutMs) throws Exception {
       if (!endedCountDownLatch.await(timeoutMs, TimeUnit.MILLISECONDS)) {
         exception = new TimeoutException("Test playback timed out.");
       }
       release();
-
       // Throw any pending exception (from playback, timing out or releasing).
       if (exception != null) {
         throw exception;
@@ -108,7 +120,7 @@ public final class ExoPlayerTest extends TestCase {
             player.setPlayWhenReady(true);
             player.prepare(new FakeMediaSource(timeline, manifest, format));
           } catch (Exception e) {
-            handlePlayerException(e);
+            handleError(e);
           }
         }
       });
@@ -123,7 +135,7 @@ public final class ExoPlayerTest extends TestCase {
               player.release();
             }
           } catch (Exception e) {
-            handlePlayerException(e);
+            handleError(e);
           } finally {
             playerThread.quit();
           }
@@ -132,7 +144,7 @@ public final class ExoPlayerTest extends TestCase {
       playerThread.join();
     }
 
-    private void handlePlayerException(Exception exception) {
+    private void handleError(Exception exception) {
       if (this.exception == null) {
         this.exception = exception;
       }
@@ -167,20 +179,13 @@ public final class ExoPlayerTest extends TestCase {
 
     @Override
     public void onPlayerError(ExoPlaybackException exception) {
-      this.exception = exception;
-      endedCountDownLatch.countDown();
+      handleError(exception);
     }
 
     @Override
     public void onPositionDiscontinuity() {
-      assertFalse(seenPositionDiscontinuity);
-      assertEquals(0, player.getCurrentWindowIndex());
-      assertEquals(0, player.getCurrentPeriodIndex());
-      assertEquals(0, player.getCurrentPosition());
-      assertEquals(0, player.getBufferedPosition());
-      assertEquals(expectedTimeline, player.getCurrentTimeline());
-      assertEquals(expectedManifest, player.getCurrentManifest());
-      seenPositionDiscontinuity = true;
+      // Should never happen.
+      handleError(new IllegalStateException("Received position discontinuity"));
     }
 
   }
@@ -194,17 +199,16 @@ public final class ExoPlayerTest extends TestCase {
     private final Timeline timeline;
     private final Object manifest;
     private final Format format;
+    private final ArrayList<FakeMediaPeriod> activeMediaPeriods;
 
-    private FakeMediaPeriod mediaPeriod;
     private boolean preparedSource;
-    private boolean releasedPeriod;
     private boolean releasedSource;
 
     public FakeMediaSource(Timeline timeline, Object manifest, Format format) {
-      Assertions.checkArgument(timeline.getPeriodCount() == 1);
       this.timeline = timeline;
       this.manifest = manifest;
       this.format = format;
+      activeMediaPeriods = new ArrayList<>();
     }
 
     @Override
@@ -221,33 +225,29 @@ public final class ExoPlayerTest extends TestCase {
 
     @Override
     public MediaPeriod createPeriod(int index, Allocator allocator, long positionUs) {
+      Assertions.checkIndex(index, 0, timeline.getPeriodCount());
       assertTrue(preparedSource);
-      assertNull(mediaPeriod);
-      assertFalse(releasedPeriod);
       assertFalse(releasedSource);
       assertEquals(0, index);
       assertEquals(0, positionUs);
-      mediaPeriod = new FakeMediaPeriod(format);
+      FakeMediaPeriod mediaPeriod = new FakeMediaPeriod(format);
+      activeMediaPeriods.add(mediaPeriod);
       return mediaPeriod;
     }
 
     @Override
     public void releasePeriod(MediaPeriod mediaPeriod) {
       assertTrue(preparedSource);
-      assertNotNull(this.mediaPeriod);
-      assertFalse(releasedPeriod);
       assertFalse(releasedSource);
-      assertEquals(this.mediaPeriod, mediaPeriod);
-      this.mediaPeriod.release();
-      releasedPeriod = true;
+      assertTrue(activeMediaPeriods.remove(mediaPeriod));
+      ((FakeMediaPeriod) mediaPeriod).release();
     }
 
     @Override
     public void releaseSource() {
       assertTrue(preparedSource);
-      assertNotNull(this.mediaPeriod);
-      assertTrue(releasedPeriod);
       assertFalse(releasedSource);
+      assertTrue(activeMediaPeriods.isEmpty());
       releasedSource = true;
     }
 
@@ -400,7 +400,6 @@ public final class ExoPlayerTest extends TestCase {
 
     public FakeVideoRenderer(Format expectedFormat) {
       super(C.TRACK_TYPE_VIDEO);
-      Assertions.checkArgument(MimeTypes.isVideo(expectedFormat.sampleMimeType));
       this.expectedFormat = expectedFormat;
     }
 

library/src/main/java/com/google/android/exoplayer2/BaseRenderer.java

@@ -267,6 +267,12 @@ public abstract class BaseRenderer implements Renderer, RendererCapabilities {
         return streamIsFinal ? C.RESULT_BUFFER_READ : C.RESULT_NOTHING_READ;
       }
       buffer.timeUs += streamOffsetUs;
+    } else if (result == C.RESULT_FORMAT_READ) {
+      Format format = formatHolder.format;
+      if (format.subsampleOffsetUs != Format.OFFSET_SAMPLE_RELATIVE) {
+        format = format.copyWithSubsampleOffsetUs(format.subsampleOffsetUs + streamOffsetUs);
+        formatHolder.format = format;
+      }
     }
     return result;
   }

library/src/main/java/com/google/android/exoplayer2/C.java

@@ -96,6 +96,13 @@ public final class C {
   @SuppressWarnings("InlinedApi")
   public static final int CRYPTO_MODE_AES_CBC = MediaCodec.CRYPTO_MODE_AES_CBC;
 
+  /**
+   * Represents an unset {@link android.media.AudioTrack} session identifier. Equal to
+   * {@link AudioManager#AUDIO_SESSION_ID_GENERATE}.
+   */
+  @SuppressWarnings("InlinedApi")
+  public static final int AUDIO_SESSION_ID_UNSET = AudioManager.AUDIO_SESSION_ID_GENERATE;
+
   /**
    * Represents an audio encoding, or an invalid or unset value.
    */

library/src/main/java/com/google/android/exoplayer2/ExoPlayerImpl.java

@@ -332,8 +332,10 @@ import java.util.concurrent.CopyOnWriteArraySet;
       case ExoPlayerImplInternal.MSG_SEEK_ACK: {
         if (--pendingSeekAcks == 0) {
           playbackInfo = (ExoPlayerImplInternal.PlaybackInfo) msg.obj;
-          for (EventListener listener : listeners) {
-            listener.onPositionDiscontinuity();
+          if (msg.arg1 != 0) {
+            for (EventListener listener : listeners) {
+              listener.onPositionDiscontinuity();
+            }
           }
         }
         break;

library/src/main/java/com/google/android/exoplayer2/ExoPlayerImplInternal.java

@@ -559,7 +559,7 @@ import java.io.IOException;
       // The seek position was valid for the timeline that it was performed into, but the
       // timeline has changed and a suitable seek position could not be resolved in the new one.
       playbackInfo = new PlaybackInfo(0, 0);
-      eventHandler.obtainMessage(MSG_SEEK_ACK, playbackInfo).sendToTarget();
+      eventHandler.obtainMessage(MSG_SEEK_ACK, 1, 0, playbackInfo).sendToTarget();
       // Set the internal position to (0,TIME_UNSET) so that a subsequent seek to (0,0) isn't
       // ignored.
       playbackInfo = new PlaybackInfo(0, C.TIME_UNSET);
@@ -569,6 +569,7 @@ import java.io.IOException;
       return;
     }
 
+    boolean seekPositionAdjusted = seekPosition.windowPositionUs == C.TIME_UNSET;
     int periodIndex = periodPosition.first;
     long periodPositionUs = periodPosition.second;
 
@@ -578,10 +579,13 @@ import java.io.IOException;
         // Seek position equals the current position. Do nothing.
         return;
       }
-      periodPositionUs = seekToPeriodPosition(periodIndex, periodPositionUs);
+      long newPeriodPositionUs = seekToPeriodPosition(periodIndex, periodPositionUs);
+      seekPositionAdjusted |= periodPositionUs != newPeriodPositionUs;
+      periodPositionUs = newPeriodPositionUs;
     } finally {
       playbackInfo = new PlaybackInfo(periodIndex, periodPositionUs);
-      eventHandler.obtainMessage(MSG_SEEK_ACK, playbackInfo).sendToTarget();
+      eventHandler.obtainMessage(MSG_SEEK_ACK, seekPositionAdjusted ? 1 : 0, 0, playbackInfo)
+          .sendToTarget();
     }
   }
 
@@ -676,6 +680,7 @@ import java.io.IOException;
     standaloneMediaClock.stop();
     rendererMediaClock = null;
     rendererMediaClockSource = null;
+    rendererPositionUs = RENDERER_TIMESTAMP_OFFSET_US;
     for (Renderer renderer : enabledRenderers) {
       try {
         ensureStopped(renderer);
@@ -823,9 +828,6 @@ import java.io.IOException;
   }
 
   private boolean haveSufficientBuffer(boolean rebuffering) {
-    if (loadingPeriodHolder == null) {
-      return false;
-    }
     long loadingPeriodBufferedPositionUs = !loadingPeriodHolder.prepared
         ? loadingPeriodHolder.startPositionUs
         : loadingPeriodHolder.mediaPeriod.getBufferedPositionUs();
@@ -1287,7 +1289,8 @@ import java.io.IOException;
   }
 
   private void maybeContinueLoading() {
-    long nextLoadPositionUs = loadingPeriodHolder.mediaPeriod.getNextLoadPositionUs();
+    long nextLoadPositionUs = !loadingPeriodHolder.prepared ? 0
+        : loadingPeriodHolder.mediaPeriod.getNextLoadPositionUs();
     if (nextLoadPositionUs == C.TIME_END_OF_SOURCE) {
       setIsLoading(false);
     } else {

library/src/main/java/com/google/android/exoplayer2/ExoPlayerLibraryInfo.java

@@ -23,7 +23,7 @@ public interface ExoPlayerLibraryInfo {
   /**
    * The version of the library, expressed as a string.
    */
-  String VERSION = "2.1.0";
+  String VERSION = "2.1.1";
 
   /**
    * The version of the library, expressed as an integer.
@@ -32,7 +32,7 @@ public interface ExoPlayerLibraryInfo {
    * corresponding integer version 1002003 (001-002-003), and "123.45.6" has the corresponding
    * integer version 123045006 (123-045-006).
    */
-  int VERSION_INT = 2001000;
+  int VERSION_INT = 2001001;
 
   /**
    * Whether the library was compiled with {@link com.google.android.exoplayer2.util.Assertions}

library/src/main/java/com/google/android/exoplayer2/SimpleExoPlayer.java

@@ -29,7 +29,6 @@ import android.view.SurfaceView;
 import android.view.TextureView;
 import com.google.android.exoplayer2.audio.AudioCapabilities;
 import com.google.android.exoplayer2.audio.AudioRendererEventListener;
-import com.google.android.exoplayer2.audio.AudioTrack;
 import com.google.android.exoplayer2.audio.MediaCodecAudioRenderer;
 import com.google.android.exoplayer2.decoder.DecoderCounters;
 import com.google.android.exoplayer2.drm.DrmSessionManager;
@@ -178,7 +177,7 @@ public class SimpleExoPlayer implements ExoPlayer {
 
     // Set initial values.
     audioVolume = 1;
-    audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+    audioSessionId = C.AUDIO_SESSION_ID_UNSET;
     audioStreamType = C.STREAM_TYPE_DEFAULT;
     videoScalingMode = C.VIDEO_SCALING_MODE_DEFAULT;
 
@@ -393,7 +392,7 @@ public class SimpleExoPlayer implements ExoPlayer {
   }
 
   /**
-   * Returns the audio session identifier, or {@code AudioTrack.SESSION_ID_NOT_SET} if not set.
+   * Returns the audio session identifier, or {@link C#AUDIO_SESSION_ID_UNSET} if not set.
    */
   public int getAudioSessionId() {
     return audioSessionId;
@@ -949,7 +948,7 @@ public class SimpleExoPlayer implements ExoPlayer {
       }
       audioFormat = null;
       audioDecoderCounters = null;
-      audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+      audioSessionId = C.AUDIO_SESSION_ID_UNSET;
     }
 
     // TextRenderer.Output implementation

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

@@ -17,6 +17,7 @@ package com.google.android.exoplayer2.audio;
 
 import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
+import android.media.AudioAttributes;
 import android.media.AudioFormat;
 import android.media.AudioTimestamp;
 import android.media.PlaybackParams;
@@ -30,26 +31,28 @@ import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.Util;
 import java.lang.reflect.Method;
 import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
 
 /**
  * Plays audio data. The implementation delegates to an {@link android.media.AudioTrack} and handles
  * playback position smoothing, non-blocking writes and reconfiguration.
  * <p>
  * Before starting playback, specify the input format by calling
- * {@link #configure(String, int, int, int, int)}. Next call {@link #initialize(int)}, optionally
- * specifying an audio session.
+ * {@link #configure(String, int, int, int, int)}. Next call {@link #initialize(int)} or
+ * {@link #initializeV21(int, boolean)}, optionally specifying an audio session and whether the
+ * track is to be used with tunneling video playback.
  * <p>
  * Call {@link #handleBuffer(ByteBuffer, long)} to write data, and {@link #handleDiscontinuity()}
  * when the data being fed is discontinuous. Call {@link #play()} to start playing the written data.
  * <p>
  * Call {@link #configure(String, int, int, int, int)} whenever the input format changes. If
  * {@link #isInitialized()} returns {@code false} after the call, it is necessary to call
- * {@link #initialize(int)} before writing more data.
+ * {@link #initialize(int)} or {@link #initializeV21(int, boolean)} before writing more data.
  * <p>
  * The underlying {@link android.media.AudioTrack} is created by {@link #initialize(int)} and
  * released by {@link #reset()} (and {@link #configure(String, int, int, int, int)} unless the input
- * format is unchanged). It is safe to call {@link #initialize(int)} after calling {@link #reset()}
- * without reconfiguration.
+ * format is unchanged). It is safe to call {@link #initialize(int)} or
+ * {@link #initializeV21(int, boolean)} after calling {@link #reset()} without reconfiguration.
  * <p>
  * Call {@link #release()} when the instance is no longer required.
  */
@@ -143,11 +146,6 @@ public final class AudioTrack {
    */
   public static final int RESULT_BUFFER_CONSUMED = 2;
 
-  /**
-   * Represents an unset {@link android.media.AudioTrack} session identifier.
-   */
-  public static final int SESSION_ID_NOT_SET = 0;
-
   /**
    * Returned by {@link #getCurrentPositionUs} when the position is not set.
    */
@@ -273,6 +271,10 @@ public final class AudioTrack {
   private int bufferSize;
   private long bufferSizeUs;
 
+  private boolean useHwAvSync;
+  private ByteBuffer avSyncHeader;
+  private int bytesUntilNextAvSync;
+
   private int nextPlayheadOffsetIndex;
   private int playheadOffsetCount;
   private long smoothedPlayheadOffsetUs;
@@ -341,8 +343,8 @@ public final class AudioTrack {
   }
 
   /**
-   * Returns whether the audio track has been successfully initialized via {@link #initialize} and
-   * not yet {@link #reset}.
+   * Returns whether the audio track has been successfully initialized via {@link #initialize} or
+   * {@link #initializeV21(int, boolean)}, and has not yet been {@link #reset}.
    */
   public boolean isInitialized() {
     return audioTrack != null;
@@ -442,6 +444,21 @@ public final class AudioTrack {
         throw new IllegalArgumentException("Unsupported channel count: " + channelCount);
     }
 
+    // Workaround for overly strict channel configuration checks on nVidia Shield.
+    if (Util.SDK_INT <= 23 && "foster".equals(Util.DEVICE) && "NVIDIA".equals(Util.MANUFACTURER)) {
+      switch(channelCount) {
+        case 7:
+          channelConfig = C.CHANNEL_OUT_7POINT1_SURROUND;
+          break;
+        case 3:
+        case 5:
+          channelConfig = AudioFormat.CHANNEL_OUT_5POINT1;
+          break;
+        default:
+          break;
+      }
+    }
+
     boolean passthrough = !MimeTypes.AUDIO_RAW.equals(mimeType);
     @C.Encoding int sourceEncoding;
     if (passthrough) {
@@ -498,11 +515,28 @@ public final class AudioTrack {
   /**
    * Initializes the audio track for writing new buffers using {@link #handleBuffer}.
    *
-   * @param sessionId Audio track session identifier to re-use, or {@link #SESSION_ID_NOT_SET} to
-   *     create a new one.
-   * @return The new (or re-used) session identifier.
+   * @param sessionId Audio track session identifier, or {@link C#AUDIO_SESSION_ID_UNSET} to create
+   *     one.
+   * @return The audio track session identifier.
    */
   public int initialize(int sessionId) throws InitializationException {
+    return initializeInternal(sessionId, false);
+  }
+
+  /**
+   * Initializes the audio track for writing new buffers using {@link #handleBuffer}.
+   *
+   * @param sessionId Audio track session identifier, or {@link C#AUDIO_SESSION_ID_UNSET} to create
+   *     one.
+   * @param tunneling Whether the audio track is to be used with tunneling video playback.
+   * @return The audio track session identifier.
+   */
+  public int initializeV21(int sessionId, boolean tunneling) throws InitializationException {
+    Assertions.checkState(Util.SDK_INT >= 21);
+    return initializeInternal(sessionId, tunneling);
+  }
+
+  private int initializeInternal(int sessionId, boolean tunneling) throws InitializationException {
     // If we're asynchronously releasing a previous audio track then we block until it has been
     // released. This guarantees that we cannot end up in a state where we have multiple audio
     // track instances. Without this guarantee it would be possible, in extreme cases, to exhaust
@@ -510,7 +544,11 @@ public final class AudioTrack {
     // initialization of the audio track to fail.
     releasingConditionVariable.block();
 
-    if (sessionId == SESSION_ID_NOT_SET) {
+    useHwAvSync = tunneling;
+    if (useHwAvSync) {
+      audioTrack = createHwAvSyncAudioTrackV21(sampleRate, channelConfig, targetEncoding,
+          bufferSize, sessionId);
+    } else if (sessionId == C.AUDIO_SESSION_ID_UNSET) {
       audioTrack = new android.media.AudioTrack(streamType, sampleRate, channelConfig,
           targetEncoding, bufferSize, MODE_STREAM);
     } else {
@@ -692,7 +730,9 @@ public final class AudioTrack {
         buffer.position(buffer.position() + bytesWritten);
       }
     } else {
-      bytesWritten = writeNonBlockingV21(audioTrack, buffer, bytesRemaining);
+      bytesWritten = useHwAvSync
+          ? writeNonBlockingWithAvSyncV21(audioTrack, buffer, bytesRemaining, presentationTimeUs)
+          : writeNonBlockingV21(audioTrack, buffer, bytesRemaining);
     }
 
     if (bytesWritten < 0) {
@@ -718,6 +758,7 @@ public final class AudioTrack {
   public void handleEndOfStream() {
     if (isInitialized()) {
       audioTrackUtil.handleEndOfStream(getSubmittedFrames());
+      bytesUntilNextAvSync = 0;
     }
   }
 
@@ -743,19 +784,27 @@ public final class AudioTrack {
   }
 
   /**
-   * Sets the stream type for audio track. If the stream type has changed, {@link #isInitialized()}
-   * will return {@code false} and the caller must re-{@link #initialize(int)} the audio track
-   * before writing more data. The caller must not reuse the audio session identifier when
-   * re-initializing with a new stream type.
+   * Sets the stream type for audio track. If the stream type has changed and if the audio track
+   * is not configured for use with video tunneling, then the audio track is reset and the caller
+   * must re-initialize the audio track before writing more data. The caller must not reuse the
+   * audio session identifier when re-initializing with a new stream type.
+   * <p>
+   * If the audio track is configured for use with video tunneling then the stream type is ignored
+   * and the audio track is not reset. The passed stream type will be used if the audio track is
+   * later re-configured into non-tunneled mode.
    *
    * @param streamType The {@link C.StreamType} to use for audio output.
-   * @return Whether the stream type changed.
+   * @return Whether the audio track was reset as a result of this call.
    */
   public boolean setStreamType(@C.StreamType int streamType) {
     if (this.streamType == streamType) {
       return false;
     }
     this.streamType = streamType;
+    if (useHwAvSync) {
+      // The stream type is ignored in tunneling mode, so no need to reset.
+      return false;
+    }
     reset();
     return true;
   }
@@ -795,9 +844,9 @@ public final class AudioTrack {
   /**
    * Releases the underlying audio track asynchronously.
    * <p>
-   * Calling {@link #initialize(int)} will block until the audio track has been released, so it is
-   * safe to initialize immediately after a reset. The audio session may remain active until
-   * {@link #release()} is called.
+   * Calling {@link #initialize(int)} or {@link #initializeV21(int, boolean)} will block until the
+   * audio track has been released, so it is safe to initialize immediately after a reset. The audio
+   * session may remain active until {@link #release()} is called.
    */
   public void reset() {
     if (isInitialized()) {
@@ -805,6 +854,7 @@ public final class AudioTrack {
       submittedEncodedFrames = 0;
       framesPerEncodedSample = 0;
       currentSourceBuffer = null;
+      avSyncHeader = null;
       startMediaTimeState = START_NOT_SET;
       latencyUs = 0;
       resetSyncParams();
@@ -1020,6 +1070,26 @@ public final class AudioTrack {
         && audioTrack.getPlaybackHeadPosition() == 0;
   }
 
+  /**
+   * Instantiates an {@link android.media.AudioTrack} to be used with tunneling video playback.
+   */
+  @TargetApi(21)
+  private static android.media.AudioTrack createHwAvSyncAudioTrackV21(int sampleRate,
+      int channelConfig, int encoding, int bufferSize, int sessionId) {
+    AudioAttributes attributesBuilder = new AudioAttributes.Builder()
+        .setUsage(AudioAttributes.USAGE_MEDIA)
+        .setContentType(AudioAttributes.CONTENT_TYPE_MOVIE)
+        .setFlags(AudioAttributes.FLAG_HW_AV_SYNC)
+        .build();
+    AudioFormat format = new AudioFormat.Builder()
+        .setChannelMask(channelConfig)
+        .setEncoding(encoding)
+        .setSampleRate(sampleRate)
+        .build();
+    return new android.media.AudioTrack(attributesBuilder, format, bufferSize, MODE_STREAM,
+        sessionId);
+  }
+
   /**
    * Converts the provided buffer into 16-bit PCM.
    *
@@ -1125,11 +1195,50 @@ public final class AudioTrack {
   }
 
   @TargetApi(21)
-  private static int writeNonBlockingV21(
-      android.media.AudioTrack audioTrack, ByteBuffer buffer, int size) {
+  private static int writeNonBlockingV21(android.media.AudioTrack audioTrack, ByteBuffer buffer,
+      int size) {
     return audioTrack.write(buffer, size, WRITE_NON_BLOCKING);
   }
 
+  @TargetApi(21)
+  private int writeNonBlockingWithAvSyncV21(android.media.AudioTrack audioTrack,
+      ByteBuffer buffer, int size, long presentationTimeUs) {
+    // TODO: Uncomment this when [Internal ref b/33627517] is clarified or fixed.
+    // if (Util.SDK_INT >= 23) {
+    //   // The underlying platform AudioTrack writes AV sync headers directly.
+    //   return audioTrack.write(buffer, size, WRITE_NON_BLOCKING, presentationTimeUs * 1000);
+    // }
+    if (avSyncHeader == null) {
+      avSyncHeader = ByteBuffer.allocate(16);
+      avSyncHeader.order(ByteOrder.BIG_ENDIAN);
+      avSyncHeader.putInt(0x55550001);
+    }
+    if (bytesUntilNextAvSync == 0) {
+      avSyncHeader.putInt(4, size);
+      avSyncHeader.putLong(8, presentationTimeUs * 1000);
+      avSyncHeader.position(0);
+      bytesUntilNextAvSync = size;
+    }
+    int avSyncHeaderBytesRemaining = avSyncHeader.remaining();
+    if (avSyncHeaderBytesRemaining > 0) {
+      int result = audioTrack.write(avSyncHeader, avSyncHeaderBytesRemaining, WRITE_NON_BLOCKING);
+      if (result < 0) {
+        bytesUntilNextAvSync = 0;
+        return result;
+      }
+      if (result < avSyncHeaderBytesRemaining) {
+        return 0;
+      }
+    }
+    int result = writeNonBlockingV21(audioTrack, buffer, size);
+    if (result < 0) {
+      bytesUntilNextAvSync = 0;
+      return result;
+    }
+    bytesUntilNextAvSync -= result;
+    return result;
+  }
+
   @TargetApi(21)
   private static void setAudioTrackVolumeV21(android.media.AudioTrack audioTrack, float volume) {
     audioTrack.setVolume(volume);

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

@@ -129,7 +129,7 @@ public class MediaCodecAudioRenderer extends MediaCodecRenderer implements Media
       boolean playClearSamplesWithoutKeys, Handler eventHandler,
       AudioRendererEventListener eventListener, AudioCapabilities audioCapabilities) {
     super(C.TRACK_TYPE_AUDIO, mediaCodecSelector, drmSessionManager, playClearSamplesWithoutKeys);
-    audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+    audioSessionId = C.AUDIO_SESSION_ID_UNSET;
     audioTrack = new AudioTrack(audioCapabilities, this);
     eventDispatcher = new EventDispatcher(eventHandler, eventListener);
   }
@@ -274,7 +274,7 @@ public class MediaCodecAudioRenderer extends MediaCodecRenderer implements Media
 
   @Override
   protected void onDisabled() {
-    audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+    audioSessionId = C.AUDIO_SESSION_ID_UNSET;
     try {
       audioTrack.release();
     } finally {
@@ -328,8 +328,8 @@ public class MediaCodecAudioRenderer extends MediaCodecRenderer implements Media
     if (!audioTrack.isInitialized()) {
       // Initialize the AudioTrack now.
       try {
-        if (audioSessionId == AudioTrack.SESSION_ID_NOT_SET) {
-          audioSessionId = audioTrack.initialize(AudioTrack.SESSION_ID_NOT_SET);
+        if (audioSessionId == C.AUDIO_SESSION_ID_UNSET) {
+          audioSessionId = audioTrack.initialize(C.AUDIO_SESSION_ID_UNSET);
           eventDispatcher.audioSessionId(audioSessionId);
           onAudioSessionId(audioSessionId);
         } else {
@@ -387,7 +387,7 @@ public class MediaCodecAudioRenderer extends MediaCodecRenderer implements Media
       case C.MSG_SET_STREAM_TYPE:
         @C.StreamType int streamType = (Integer) message;
         if (audioTrack.setStreamType(streamType)) {
-          audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+          audioSessionId = C.AUDIO_SESSION_ID_UNSET;
         }
         break;
       default:

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

@@ -145,7 +145,7 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
     this.drmSessionManager = drmSessionManager;
     formatHolder = new FormatHolder();
     this.playClearSamplesWithoutKeys = playClearSamplesWithoutKeys;
-    audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+    audioSessionId = C.AUDIO_SESSION_ID_UNSET;
     decoderReinitializationState = REINITIALIZATION_STATE_NONE;
     audioTrackNeedsConfigure = true;
   }
@@ -245,8 +245,8 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
     }
 
     if (!audioTrack.isInitialized()) {
-      if (audioSessionId == AudioTrack.SESSION_ID_NOT_SET) {
-        audioSessionId = audioTrack.initialize(AudioTrack.SESSION_ID_NOT_SET);
+      if (audioSessionId == C.AUDIO_SESSION_ID_UNSET) {
+        audioSessionId = audioTrack.initialize(C.AUDIO_SESSION_ID_UNSET);
         eventDispatcher.audioSessionId(audioSessionId);
         onAudioSessionId(audioSessionId);
       } else {
@@ -425,7 +425,7 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
   @Override
   protected void onDisabled() {
     inputFormat = null;
-    audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+    audioSessionId = C.AUDIO_SESSION_ID_UNSET;
     audioTrackNeedsConfigure = true;
     waitingForKeys = false;
     try {
@@ -554,7 +554,7 @@ public abstract class SimpleDecoderAudioRenderer extends BaseRenderer implements
       case C.MSG_SET_STREAM_TYPE:
         @C.StreamType int streamType = (Integer) message;
         if (audioTrack.setStreamType(streamType)) {
-          audioSessionId = AudioTrack.SESSION_ID_NOT_SET;
+          audioSessionId = C.AUDIO_SESSION_ID_UNSET;
         }
         break;
       default:

library/src/main/java/com/google/android/exoplayer2/source/ExtractorMediaPeriod.java

@@ -244,7 +244,7 @@ import java.io.IOException;
 
   @Override
   public long getNextLoadPositionUs() {
-    return getBufferedPositionUs();
+    return enabledTrackCount == 0 ? C.TIME_END_OF_SOURCE : getBufferedPositionUs();
   }
 
   @Override

library/src/main/java/com/google/android/exoplayer2/source/MediaPeriod.java

@@ -133,4 +133,32 @@ public interface MediaPeriod extends SequenceableLoader {
    */
   long seekToUs(long positionUs);
 
+  // SequenceableLoader interface. Overridden to provide more specific documentation.
+
+  /**
+   * Returns the next load time, or {@link C#TIME_END_OF_SOURCE} if loading has finished.
+   * <p>
+   * This method should only be called after the period has been prepared. It may be called when no
+   * tracks are selected.
+   */
+  @Override
+  long getNextLoadPositionUs();
+
+  /**
+   * Attempts to continue loading.
+   * <p>
+   * This method may be called both during and after the period has been prepared.
+   * <p>
+   * A period may call {@link Callback#onContinueLoadingRequested(SequenceableLoader)} on the
+   * {@link Callback} passed to {@link #prepare(Callback)} to request that this method be called
+   * when the period is permitted to continue loading data. A period may do this both during and
+   * after preparation.
+   *
+   * @param positionUs The current playback position.
+   * @return True if progress was made, meaning that {@link #getNextLoadPositionUs()} will return
+   *     a different value than prior to the call. False otherwise.
+   */
+  @Override
+  boolean continueLoading(long positionUs);
+
 }

library/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaSource.java

@@ -104,15 +104,14 @@ public final class HlsMediaSource implements MediaSource,
     SinglePeriodTimeline timeline;
     if (playlistTracker.isLive()) {
       // TODO: fix windowPositionInPeriodUs when playlist is empty.
-      long windowPositionInPeriodUs = playlist.startTimeUs;
       List<HlsMediaPlaylist.Segment> segments = playlist.segments;
       long windowDefaultStartPositionUs = segments.isEmpty() ? 0
           : segments.get(Math.max(0, segments.size() - 3)).relativeStartTimeUs;
       timeline = new SinglePeriodTimeline(C.TIME_UNSET, playlist.durationUs,
-          windowPositionInPeriodUs, windowDefaultStartPositionUs, true, !playlist.hasEndTag);
+          playlist.startTimeUs, windowDefaultStartPositionUs, true, !playlist.hasEndTag);
     } else /* not live */ {
-      timeline = new SinglePeriodTimeline(playlist.durationUs, playlist.durationUs, 0, 0, true,
-          false);
+      timeline = new SinglePeriodTimeline(playlist.startTimeUs + playlist.durationUs,
+          playlist.durationUs, playlist.startTimeUs, 0, true, false);
     }
     sourceListener.onSourceInfoRefreshed(timeline, playlist);
   }

library/src/main/java/com/google/android/exoplayer2/text/Cue.java

@@ -15,6 +15,7 @@
  */
 package com.google.android.exoplayer2.text;
 
+import android.graphics.Color;
 import android.support.annotation.IntDef;
 import android.text.Layout.Alignment;
 import java.lang.annotation.Retention;
@@ -36,19 +37,23 @@ public class Cue {
   @Retention(RetentionPolicy.SOURCE)
   @IntDef({TYPE_UNSET, ANCHOR_TYPE_START, ANCHOR_TYPE_MIDDLE, ANCHOR_TYPE_END})
   public @interface AnchorType {}
+
   /**
    * An unset anchor or line type value.
    */
   public static final int TYPE_UNSET = Integer.MIN_VALUE;
+
   /**
    * Anchors the left (for horizontal positions) or top (for vertical positions) edge of the cue
    * box.
    */
   public static final int ANCHOR_TYPE_START = 0;
+
   /**
    * Anchors the middle of the cue box.
    */
   public static final int ANCHOR_TYPE_MIDDLE = 1;
+
   /**
    * Anchors the right (for horizontal positions) or bottom (for vertical positions) edge of the cue
    * box.
@@ -61,10 +66,12 @@ public class Cue {
   @Retention(RetentionPolicy.SOURCE)
   @IntDef({TYPE_UNSET, LINE_TYPE_FRACTION, LINE_TYPE_NUMBER})
   public @interface LineType {}
+
   /**
    * Value for {@link #lineType} when {@link #line} is a fractional position.
    */
   public static final int LINE_TYPE_FRACTION = 0;
+
   /**
    * Value for {@link #lineType} when {@link #line} is a line number.
    */
@@ -74,10 +81,12 @@ public class Cue {
    * The cue text. Note the {@link CharSequence} may be decorated with styling spans.
    */
   public final CharSequence text;
+
   /**
    * The alignment of the cue text within the cue box, or null if the alignment is undefined.
    */
   public final Alignment textAlignment;
+
   /**
    * The position of the {@link #lineAnchor} of the cue box within the viewport in the direction
    * orthogonal to the writing direction, or {@link #DIMEN_UNSET}. When set, the interpretation of
@@ -86,6 +95,7 @@ public class Cue {
    * For horizontal text and {@link #lineType} equal to {@link #LINE_TYPE_FRACTION}, this is the
    * fractional vertical position relative to the top of the viewport.
    */
+
   public final float line;
   /**
    * The type of the {@link #line} value.
@@ -112,6 +122,7 @@ public class Cue {
    * {@code (line == -2 && lineAnchor == ANCHOR_TYPE_START)} position a cue so that only its first
    * line is visible at the bottom of the viewport.
    */
+
   @LineType
   public final int lineType;
   /**
@@ -122,6 +133,7 @@ public class Cue {
    * and {@link #ANCHOR_TYPE_END} correspond to the top, middle and bottom of the cue box
    * respectively.
    */
+
   @AnchorType
   public final int lineAnchor;
   /**
@@ -133,6 +145,7 @@ public class Cue {
    * text.
    */
   public final float position;
+
   /**
    * The cue box anchor positioned by {@link #position}. One of {@link #ANCHOR_TYPE_START},
    * {@link #ANCHOR_TYPE_MIDDLE}, {@link #ANCHOR_TYPE_END} and {@link #TYPE_UNSET}.
@@ -143,12 +156,23 @@ public class Cue {
    */
   @AnchorType
   public final int positionAnchor;
+
   /**
    * The size of the cue box in the writing direction specified as a fraction of the viewport size
    * in that direction, or {@link #DIMEN_UNSET}.
    */
   public final float size;
 
+  /**
+   * Specifies whether or not the {@link #windowColor} property is set.
+   */
+  public final boolean windowColorSet;
+
+  /**
+   * The fill color of the window.
+   */
+  public final int windowColor;
+
   /**
    * Constructs a cue whose {@link #textAlignment} is null, whose type parameters are set to
    * {@link #TYPE_UNSET} and whose dimension parameters are set to {@link #DIMEN_UNSET}.
@@ -171,6 +195,25 @@ public class Cue {
    */
   public Cue(CharSequence text, Alignment textAlignment, float line, @LineType int lineType,
       @AnchorType int lineAnchor, float position, @AnchorType int positionAnchor, float size) {
+    this(text, textAlignment, line, lineType, lineAnchor, position, positionAnchor, size, false,
+        Color.BLACK);
+  }
+
+  /**
+   * @param text See {@link #text}.
+   * @param textAlignment See {@link #textAlignment}.
+   * @param line See {@link #line}.
+   * @param lineType See {@link #lineType}.
+   * @param lineAnchor See {@link #lineAnchor}.
+   * @param position See {@link #position}.
+   * @param positionAnchor See {@link #positionAnchor}.
+   * @param size See {@link #size}.
+   * @param windowColorSet See {@link #windowColorSet}.
+   * @param windowColor See {@link #windowColor}.
+   */
+  public Cue(CharSequence text, Alignment textAlignment, float line, @LineType int lineType,
+      @AnchorType int lineAnchor, float position, @AnchorType int positionAnchor, float size,
+      boolean windowColorSet, int windowColor) {
     this.text = text;
     this.textAlignment = textAlignment;
     this.line = line;
@@ -179,6 +222,8 @@ public class Cue {
     this.position = position;
     this.positionAnchor = positionAnchor;
     this.size = size;
+    this.windowColorSet = windowColorSet;
+    this.windowColor = windowColor;
   }
 
 }

library/src/main/java/com/google/android/exoplayer2/ui/SimpleExoPlayerView.java

@@ -65,6 +65,13 @@ import java.util.List;
  *         <li>Default: {@code true}</li>
  *       </ul>
  *   </li>
+ *   <li><b>{@code default_artwork}</b> - Default artwork to use if no artwork available in audio
+ *       streams.
+ *       <ul>
+ *         <li>Corresponding method: {@link #setDefaultArtwork(Bitmap)}</li>
+ *         <li>Default: {@code null}</li>
+ *       </ul>
+ *   </li>
  *   <li><b>{@code use_controller}</b> - Whether playback controls are displayed.
  *       <ul>
  *         <li>Corresponding method: {@link #setUseController(boolean)}</li>
@@ -179,6 +186,7 @@ public final class SimpleExoPlayerView extends FrameLayout {
   private SimpleExoPlayer player;
   private boolean useController;
   private boolean useArtwork;
+  private Bitmap defaultArtwork;
   private int controllerShowTimeoutMs;
 
   public SimpleExoPlayerView(Context context) {
@@ -194,6 +202,7 @@ public final class SimpleExoPlayerView extends FrameLayout {
 
     int playerLayoutId = R.layout.exo_simple_player_view;
     boolean useArtwork = true;
+    int defaultArtwork = 0;
     boolean useController = true;
     int surfaceType = SURFACE_TYPE_SURFACE_VIEW;
     int resizeMode = AspectRatioFrameLayout.RESIZE_MODE_FIT;
@@ -205,6 +214,8 @@ public final class SimpleExoPlayerView extends FrameLayout {
         playerLayoutId = a.getResourceId(R.styleable.SimpleExoPlayerView_player_layout_id,
             playerLayoutId);
         useArtwork = a.getBoolean(R.styleable.SimpleExoPlayerView_use_artwork, useArtwork);
+        defaultArtwork = a.getResourceId(R.styleable.SimpleExoPlayerView_default_artwork,
+                defaultArtwork);
         useController = a.getBoolean(R.styleable.SimpleExoPlayerView_use_controller, useController);
         surfaceType = a.getInt(R.styleable.SimpleExoPlayerView_surface_type, surfaceType);
         resizeMode = a.getInt(R.styleable.SimpleExoPlayerView_resize_mode, resizeMode);
@@ -246,6 +257,9 @@ public final class SimpleExoPlayerView extends FrameLayout {
     // Artwork view.
     artworkView = (ImageView) findViewById(R.id.exo_artwork);
     this.useArtwork = useArtwork && artworkView != null;
+    if (defaultArtwork != 0) {
+      this.defaultArtwork = BitmapFactory.decodeResource(context.getResources(), defaultArtwork);
+    }
 
     // Subtitle view.
     subtitleView = (SubtitleView) findViewById(R.id.exo_subtitles);
@@ -351,6 +365,26 @@ public final class SimpleExoPlayerView extends FrameLayout {
     }
   }
 
+  /**
+   * Returns the default artwork to display.
+   */
+  public Bitmap getDefaultArtwork() {
+    return defaultArtwork;
+  }
+
+  /**
+   * Sets the default artwork to display if {@code useArtwork} is {@code true} and no artwork is
+   * present in the media.
+   *
+   * @param defaultArtwork the default artwork to display.
+   */
+  public void setDefaultArtwork(Bitmap defaultArtwork) {
+    if (this.defaultArtwork != defaultArtwork) {
+      this.defaultArtwork = defaultArtwork;
+      updateForCurrentTrackSelections();
+    }
+  }
+
   /**
    * Returns whether the playback controls are enabled.
    */
@@ -569,6 +603,9 @@ public final class SimpleExoPlayerView extends FrameLayout {
           }
         }
       }
+      if (setArtworkFromBitmap(defaultArtwork)) {
+        return;
+      }
     }
     // Artwork disabled or unavailable.
     hideArtwork();
@@ -580,18 +617,23 @@ public final class SimpleExoPlayerView extends FrameLayout {
       if (metadataEntry instanceof ApicFrame) {
         byte[] bitmapData = ((ApicFrame) metadataEntry).pictureData;
         Bitmap bitmap = BitmapFactory.decodeByteArray(bitmapData, 0, bitmapData.length);
-        if (bitmap != null) {
-          int bitmapWidth = bitmap.getWidth();
-          int bitmapHeight = bitmap.getHeight();
-          if (bitmapWidth > 0 && bitmapHeight > 0) {
-            if (contentFrame != null) {
-              contentFrame.setAspectRatio((float) bitmapWidth / bitmapHeight);
-            }
-            artworkView.setImageBitmap(bitmap);
-            artworkView.setVisibility(VISIBLE);
-            return true;
-          }
+        return setArtworkFromBitmap(bitmap);
+      }
+    }
+    return false;
+  }
+
+  private boolean setArtworkFromBitmap(Bitmap bitmap) {
+    if (bitmap != null) {
+      int bitmapWidth = bitmap.getWidth();
+      int bitmapHeight = bitmap.getHeight();
+      if (bitmapWidth > 0 && bitmapHeight > 0) {
+        if (contentFrame != null) {
+          contentFrame.setAspectRatio((float) bitmapWidth / bitmapHeight);
         }
+        artworkView.setImageBitmap(bitmap);
+        artworkView.setVisibility(VISIBLE);
+        return true;
       }
     }
     return false;

library/src/main/java/com/google/android/exoplayer2/ui/SubtitlePainter.java

@@ -146,9 +146,13 @@ import com.google.android.exoplayer2.util.Util;
       // Nothing to draw.
       return;
     }
+
+    int windowColor = cue.windowColorSet ? cue.windowColor : style.windowColor;
+
     if (!applyEmbeddedStyles) {
       // Strip out any embedded styling.
       cueText = cueText.toString();
+      windowColor = style.windowColor;
     }
     if (areCharSequencesEqual(this.cueText, cueText)
         && Util.areEqual(this.cueTextAlignment, cue.textAlignment)
@@ -161,7 +165,7 @@ import com.google.android.exoplayer2.util.Util;
         && this.applyEmbeddedStyles == applyEmbeddedStyles
         && this.foregroundColor == style.foregroundColor
         && this.backgroundColor == style.backgroundColor
-        && this.windowColor == style.windowColor
+        && this.windowColor == windowColor
         && this.edgeType == style.edgeType
         && this.edgeColor == style.edgeColor
         && Util.areEqual(this.textPaint.getTypeface(), style.typeface)
@@ -187,7 +191,7 @@ import com.google.android.exoplayer2.util.Util;
     this.applyEmbeddedStyles = applyEmbeddedStyles;
     this.foregroundColor = style.foregroundColor;
     this.backgroundColor = style.backgroundColor;
-    this.windowColor = style.windowColor;
+    this.windowColor = windowColor;
     this.edgeType = style.edgeType;
     this.edgeColor = style.edgeColor;
     this.textPaint.setTypeface(style.typeface);

library/src/main/java/com/google/android/exoplayer2/video/MediaCodecVideoRenderer.java

@@ -403,7 +403,7 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
         bufferPresentationTimeUs, unadjustedFrameReleaseTimeNs);
     earlyUs = (adjustedReleaseTimeNs - systemTimeNs) / 1000;
 
-    if (earlyUs < -30000) {
+    if (shouldDropOutputBuffer(earlyUs, elapsedRealtimeUs)) {
       // We're more than 30ms late rendering the frame.
       dropOutputBuffer(codec, bufferIndex);
       return true;
@@ -437,6 +437,17 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
     return false;
   }
 
+  /**
+   * Returns true if the current frame should be dropped.
+   *
+   * @param earlyUs Time indicating how early the frame is. Negative values indicate late frame.
+   * @param elapsedRealtimeUs Wall clock time.
+   */
+  protected boolean shouldDropOutputBuffer(long earlyUs, long elapsedRealtimeUs) {
+    // Drop the frame if we're more than 30ms late rendering the frame.
+    return earlyUs < -30000;
+  }
+
   private void skipOutputBuffer(MediaCodec codec, int bufferIndex) {
     TraceUtil.beginSection("skipVideoBuffer");
     codec.releaseOutputBuffer(bufferIndex, false);

library/src/main/res/drawable-v21/exo_controls_fastforward.xml

@@ -0,0 +1,8 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+  android:width="32dp"
+  android:height="32dp"
+  android:viewportHeight="24.0"
+  android:viewportWidth="24.0">
+
+  <path android:fillColor="#FFF" android:pathData="M4,18l8.5,-6L4,6v12zM13,6v12l8.5,-6L13,6z"/>
+</vector>

library/src/main/res/drawable-v21/exo_controls_next.xml

@@ -0,0 +1,8 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+  android:width="32dp"
+  android:height="32dp"
+  android:viewportHeight="24.0"
+  android:viewportWidth="24.0">
+
+  <path android:fillColor="#FFF" android:pathData="M6,18l8.5,-6L6,6v12zM16,6v12h2V6h-2z"/>
+</vector>

library/src/main/res/drawable-v21/exo_controls_pause.xml

@@ -0,0 +1,8 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+  android:width="32dp"
+  android:height="32dp"
+  android:viewportHeight="24.0"
+  android:viewportWidth="24.0">
+
+  <path android:fillColor="#FFF" android:pathData="M6,19h4L10,5L6,5v14zM14,5v14h4L18,5h-4z"/>
+</vector>

library/src/main/res/drawable-v21/exo_controls_play.xml

@@ -0,0 +1,8 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+  android:width="32dp"
+  android:height="32dp"
+  android:viewportHeight="24.0"
+  android:viewportWidth="24.0">
+
+  <path android:fillColor="#FFF" android:pathData="M8,5v14l11,-7z"/>
+</vector>

library/src/main/res/drawable-v21/exo_controls_previous.xml

@@ -0,0 +1,8 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+  android:width="32dp"
+  android:height="32dp"
+  android:viewportHeight="24.0"
+  android:viewportWidth="24.0">
+
+  <path android:fillColor="#FFF" android:pathData="M6,6h2v12L6,18zM9.5,12l8.5,6L18,6z"/>
+</vector>

library/src/main/res/drawable-v21/exo_controls_rewind.xml

@@ -0,0 +1,8 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+  android:width="32dp"
+  android:height="32dp"
+  android:viewportHeight="24.0"
+  android:viewportWidth="24.0">
+
+  <path android:fillColor="#FFF" android:pathData="M11,18L11,6l-8.5,6 8.5,6zM11.5,12l8.5,6L20,6l-8.5,6z"/>
+</vector>

library/src/main/res/values/attrs.xml

@@ -37,6 +37,7 @@
 
   <declare-styleable name="SimpleExoPlayerView">
     <attr name="use_artwork" format="boolean"/>
+    <attr name="default_artwork" format="reference"/>
     <attr name="use_controller" format="boolean"/>
     <attr name="surface_type"/>
     <attr name="show_timeout"/>