Merge branch 'dev-v2' into dev-v2

49a99bea · Michał Seroczyński · GitHub · 3390b216 · 254589cb · 49a99bea
Commit 49a99bea authored Dec 17, 2018 by Michał Seroczyński Committed by GitHub Dec 17, 2018
Showing with 1557 additions and 718 deletions
RELEASENOTES.md
demos/cast/build.gradle
demos/cast/src/main/AndroidManifest.xml
demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/DefaultReceiverPlayerManager.java
demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/DemoUtil.java
demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/MainActivity.java
demos/main/src/main/java/com/google/android/exoplayer2/demo/DemoApplication.java
demos/main/src/main/java/com/google/android/exoplayer2/demo/DemoDownloadService.java
demos/main/src/main/java/com/google/android/exoplayer2/demo/DownloadTracker.java
demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java
demos/main/src/main/java/com/google/android/exoplayer2/demo/SampleChooserActivity.java
demos/main/src/main/res/drawable-hdpi/ic_edit.png
demos/main/src/main/res/drawable-mdpi/ic_edit.png
demos/main/src/main/res/drawable-xhdpi/ic_edit.png
demos/main/src/main/res/drawable-xxhdpi/ic_edit.png
demos/main/src/main/res/drawable-xxxhdpi/ic_edit.png
demos/main/src/main/res/layout/download_track_item.xml
demos/main/src/main/res/layout/start_download_dialog.xml
demos/main/src/main/res/values/strings.xml
extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/TimelineQueueEditor.java
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -5,15 +5,37 @@
 * Support for playing spherical videos on Daydream.
 * Improve decoder re-use between playbacks. TODO: Write and link a blog post
  here ([#2826](https://github.com/google/ExoPlayer/issues/2826)).
-* Add options for controlling audio track selections to `DefaultTrackSelector`
+* Track selection:
-  ([#3314](https://github.com/google/ExoPlayer/issues/3314)).
+  * Add options for controlling audio track selections to `DefaultTrackSelector`
+    ([#3314](https://github.com/google/ExoPlayer/issues/3314)).
+  * Update `TrackSelection.Factory` interface to support creating all track
+    selections together.
+* Captions:
+  * Support PNG subtitles in SMPTE-TT
+    ([#1583](https://github.com/google/ExoPlayer/issues/1583)).
 * Do not retry failed loads whose error is `FileNotFoundException`.
-* Prevent Cea608Decoder from generating Subtitles with null Cues list
+* Prevent Cea608Decoder from generating Subtitles with null Cues list.
-* Caching: Cache data with unknown length by default. The previous flag to opt in
+* Offline:
-  to this behavior (`DataSpec.FLAG_ALLOW_CACHING_UNKNOWN_LENGTH`) has been
+  * Speed up removal of segmented downloads
-  replaced with an opt out flag (`DataSpec.FLAG_DONT_CACHE_IF_LENGTH_UNKNOWN`).
+    ([#5136](https://github.com/google/ExoPlayer/issues/5136)).
+  * Add `setStreamKeys` method to factories of DASH, SmoothStreaming and HLS
+    media sources to simplify filtering by downloaded streams.
+* Caching:
+  * Improve performance of `SimpleCache`.
+  * Cache data with unknown length by default. The previous flag to opt in to
+    this behavior (`DataSpec.FLAG_ALLOW_CACHING_UNKNOWN_LENGTH`) has been
+    replaced with an opt out flag
+    (`DataSpec.FLAG_DONT_CACHE_IF_LENGTH_UNKNOWN`).
+* Disable post processing on Nvidia devices, as it breaks decode-only frame
+  skippping.
+* Workaround for MiTV (dangal) issue when swapping output surface
+  ([#5169](https://github.com/google/ExoPlayer/issues/5169)).
+* DownloadManager:
+  * Create only one task for all DownloadActions for the same content.
+  * Rename TaskState to DownloadState.
 * MP3: Fix issue where streams would play twice on Samsung devices
  ([#4519](https://github.com/google/ExoPlayer/issues/4519)).
 ### 2.9.2 ###
 * HLS:
@@ -61,10 +83,10 @@
 * DASH: Parse ProgramInformation element if present in the manifest.
 * HLS:
  * Add constructor to `DefaultHlsExtractorFactory` for adding TS payload
-    reader factory flags.
+    reader factory flags
+    ([#4861](https://github.com/google/ExoPlayer/issues/4861)).
  * Fix bug in segment sniffing
    ([#5039](https://github.com/google/ExoPlayer/issues/5039)).
-  ([#4861](https://github.com/google/ExoPlayer/issues/4861)).
 * SubRip: Add support for alignment tags, and remove tags from the displayed
  captions ([#4306](https://github.com/google/ExoPlayer/issues/4306)).
 * Fix issue with blind seeking to windows with non-zero offset in a

--- a/demos/cast/build.gradle
+++ b/demos/cast/build.gradle
@@ -49,6 +49,16 @@ android {
        disable 'MissingTranslation'
    }
+    flavorDimensions "receiver"
+    productFlavors {
+        defaultCast {
+            dimension "receiver"
+            manifestPlaceholders =
+                    [castOptionsProvider: "com.google.android.exoplayer2.ext.cast.DefaultCastOptionsProvider"]
+        }
+    }
 }
 dependencies {

--- a/demos/cast/src/main/AndroidManifest.xml
+++ b/demos/cast/src/main/AndroidManifest.xml
@@ -23,7 +23,7 @@
      android:largeHeap="true" android:allowBackup="false">
    <meta-data android:name="com.google.android.gms.cast.framework.OPTIONS_PROVIDER_CLASS_NAME"
-        android:value="com.google.android.exoplayer2.ext.cast.DefaultCastOptionsProvider" />
+        android:value="${castOptionsProvider}" />
    <activity android:name="com.google.android.exoplayer2.castdemo.MainActivity"
        android:configChanges="keyboard|keyboardHidden|orientation|screenSize|screenLayout|smallestScreenSize|uiMode"

--- a/demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/DefaultReceiverPlayerManager.java
+++ b/demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/DefaultReceiverPlayerManager.java
@@ -268,7 +268,7 @@ import java.util.ArrayList;
  public void onTimelineChanged(
      Timeline timeline, @Nullable Object manifest, @TimelineChangeReason int reason) {
    updateCurrentItemIndex();
-    if (timeline.isEmpty()) {
+    if (currentPlayer == castPlayer && timeline.isEmpty()) {
      castMediaQueueCreationPending = true;
    }
  }

--- a/demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/DemoUtil.java
+++ b/demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/DemoUtil.java
@@ -15,7 +15,6 @@
 */
 package com.google.android.exoplayer2.castdemo;
-import com.google.android.exoplayer2.ext.cast.MediaItem;
 import com.google.android.exoplayer2.util.MimeTypes;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -24,50 +23,64 @@ import java.util.List;
 /** Utility methods and constants for the Cast demo application. */
 /* package */ final class DemoUtil {
+  /** Represents a media sample. */
+  public static final class Sample {
+    /** The uri of the media content. */
+    public final String uri;
+    /** The name of the sample. */
+    public final String name;
+    /** The mime type of the sample media content. */
+    public final String mimeType;
+    /**
+     * @param uri See {@link #uri}.
+     * @param name See {@link #name}.
+     * @param mimeType See {@link #mimeType}.
+     */
+    public Sample(String uri, String name, String mimeType) {
+      this.uri = uri;
+      this.name = name;
+      this.mimeType = mimeType;
+    }
+    @Override
+    public String toString() {
+      return name;
+    }
+  }
  public static final String MIME_TYPE_DASH = MimeTypes.APPLICATION_MPD;
  public static final String MIME_TYPE_HLS = MimeTypes.APPLICATION_M3U8;
  public static final String MIME_TYPE_SS = MimeTypes.APPLICATION_SS;
  public static final String MIME_TYPE_VIDEO_MP4 = MimeTypes.VIDEO_MP4;
  /** The list of samples available in the cast demo app. */
-  public static final List<MediaItem> SAMPLES;
+  public static final List<Sample> SAMPLES;
  static {
    // App samples.
-    ArrayList<MediaItem> samples = new ArrayList<>();
+    ArrayList<Sample> samples = new ArrayList<>();
-    MediaItem.Builder sampleBuilder = new MediaItem.Builder();
    samples.add(
-        sampleBuilder
+        new Sample(
-            .setTitle("DASH (clear,MP4,H264)")
+            "https://storage.googleapis.com/wvmedia/clear/h264/tears/tears.mpd",
-            .setMimeType(MIME_TYPE_DASH)
+            "DASH (clear,MP4,H264)",
-            .setMedia("https://storage.googleapis.com/wvmedia/clear/h264/tears/tears.mpd")
+            MIME_TYPE_DASH));
-            .buildAndClear());
    samples.add(
-        sampleBuilder
+        new Sample(
-            .setTitle("Tears of Steel (HLS)")
+            "https://commondatastorage.googleapis.com/gtv-videos-bucket/CastVideos/"
-            .setMimeType(MIME_TYPE_HLS)
+                + "hls/TearsOfSteel.m3u8",
-            .setMedia(
+            "Tears of Steel (HLS)",
-                "https://commondatastorage.googleapis.com/gtv-videos-bucket/CastVideos/"
+            MIME_TYPE_HLS));
-                    + "hls/TearsOfSteel.m3u8")
-            .buildAndClear());
    samples.add(
-        sampleBuilder
+        new Sample(
-            .setTitle("HLS Basic (TS)")
+            "https://devstreaming-cdn.apple.com/videos/streaming/examples/bipbop_4x3"
-            .setMimeType(MIME_TYPE_HLS)
+                + "/bipbop_4x3_variant.m3u8",
-            .setMedia(
+            "HLS Basic (TS)",
-                "https://devstreaming-cdn.apple.com/videos/streaming/examples/bipbop_4x3"
+            MIME_TYPE_HLS));
-                    + "/bipbop_4x3_variant.m3u8")
-            .buildAndClear());
    samples.add(
-        sampleBuilder
+        new Sample("https://html5demos.com/assets/dizzy.mp4", "Dizzy (MP4)", MIME_TYPE_VIDEO_MP4));
-            .setTitle("Dizzy (MP4)")
-            .setMimeType(MIME_TYPE_VIDEO_MP4)
-            .setMedia("https://html5demos.com/assets/dizzy.mp4")
-            .buildAndClear());
    SAMPLES = Collections.unmodifiableList(samples);
  }

--- a/demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/MainActivity.java
+++ b/demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/MainActivity.java
@@ -17,7 +17,6 @@ package com.google.android.exoplayer2.castdemo;
 import android.content.Context;
 import android.os.Bundle;
-import android.support.annotation.Nullable;
 import android.support.v4.graphics.ColorUtils;
 import android.support.v7.app.AlertDialog;
 import android.support.v7.app.AppCompatActivity;
@@ -50,6 +49,8 @@ import com.google.android.gms.cast.framework.CastContext;
 public class MainActivity extends AppCompatActivity
    implements OnClickListener, PlayerManager.QueuePositionListener {
+  private final MediaItem.Builder mediaItemBuilder;
  private PlayerView localPlayerView;
  private PlayerControlView castControlView;
  private PlayerManager playerManager;
@@ -57,6 +58,10 @@ public class MainActivity extends AppCompatActivity
  private MediaQueueListAdapter mediaQueueListAdapter;
  private CastContext castContext;
+  public MainActivity() {
+    mediaItemBuilder = new MediaItem.Builder();
+  }
  // Activity lifecycle methods.
  @Override
@@ -154,7 +159,14 @@ public class MainActivity extends AppCompatActivity
    sampleList.setAdapter(new SampleListAdapter(this));
    sampleList.setOnItemClickListener(
        (parent, view, position, id) -> {
-          playerManager.addItem(DemoUtil.SAMPLES.get(position));
+          DemoUtil.Sample sample = DemoUtil.SAMPLES.get(position);
+          playerManager.addItem(
+              mediaItemBuilder
+                  .clear()
+                  .setMedia(sample.uri)
+                  .setTitle(sample.name)
+                  .setMimeType(sample.mimeType)
+                  .build());
          mediaQueueListAdapter.notifyItemInserted(playerManager.getMediaQueueSize() - 1);
        });
    return dialogList;
@@ -254,19 +266,11 @@ public class MainActivity extends AppCompatActivity
  }
-  private static final class SampleListAdapter extends ArrayAdapter<MediaItem> {
+  private static final class SampleListAdapter extends ArrayAdapter<DemoUtil.Sample> {
    public SampleListAdapter(Context context) {
      super(context, android.R.layout.simple_list_item_1, DemoUtil.SAMPLES);
    }
-    @Override
-    public View getView(int position, @Nullable View convertView, ViewGroup parent) {
-      TextView view = (TextView) super.getView(position, convertView, parent);
-      MediaItem sample = DemoUtil.SAMPLES.get(position);
-      view.setText(sample.title);
-      return view;
-    }
  }
 }
--- a/demos/main/src/main/java/com/google/android/exoplayer2/demo/DemoApplication.java
+++ b/demos/main/src/main/java/com/google/android/exoplayer2/demo/DemoApplication.java
@@ -16,6 +16,8 @@
 package com.google.android.exoplayer2.demo;
 import android.app.Application;
+import com.google.android.exoplayer2.DefaultRenderersFactory;
+import com.google.android.exoplayer2.RenderersFactory;
 import com.google.android.exoplayer2.offline.DefaultDownloaderFactory;
 import com.google.android.exoplayer2.offline.DownloadManager;
 import com.google.android.exoplayer2.offline.DownloaderConstructorHelper;
@@ -72,6 +74,17 @@ public class DemoApplication extends Application {
    return "withExtensions".equals(BuildConfig.FLAVOR);
  }
+  public RenderersFactory buildRenderersFactory(boolean preferExtensionRenderer) {
+    @DefaultRenderersFactory.ExtensionRendererMode
+    int extensionRendererMode =
+        useExtensionRenderers()
+            ? (preferExtensionRenderer
+                ? DefaultRenderersFactory.EXTENSION_RENDERER_MODE_PREFER
+                : DefaultRenderersFactory.EXTENSION_RENDERER_MODE_ON)
+            : DefaultRenderersFactory.EXTENSION_RENDERER_MODE_OFF;
+    return new DefaultRenderersFactory(this, extensionRendererMode);
+  }
  public DownloadManager getDownloadManager() {
    initDownloadManager();
    return downloadManager;

--- a/demos/main/src/main/java/com/google/android/exoplayer2/demo/DemoDownloadService.java
+++ b/demos/main/src/main/java/com/google/android/exoplayer2/demo/DemoDownloadService.java
@@ -17,7 +17,7 @@ package com.google.android.exoplayer2.demo;
 import android.app.Notification;
 import com.google.android.exoplayer2.offline.DownloadManager;
-import com.google.android.exoplayer2.offline.DownloadManager.TaskState;
+import com.google.android.exoplayer2.offline.DownloadManager.DownloadState;
 import com.google.android.exoplayer2.offline.DownloadService;
 import com.google.android.exoplayer2.scheduler.PlatformScheduler;
 import com.google.android.exoplayer2.ui.DownloadNotificationUtil;
@@ -31,12 +31,15 @@ public class DemoDownloadService extends DownloadService {
  private static final int JOB_ID = 1;
  private static final int FOREGROUND_NOTIFICATION_ID = 1;
+  private static int nextNotificationId = FOREGROUND_NOTIFICATION_ID + 1;
  public DemoDownloadService() {
    super(
        FOREGROUND_NOTIFICATION_ID,
        DEFAULT_FOREGROUND_NOTIFICATION_UPDATE_INTERVAL,
        CHANNEL_ID,
        R.string.exo_download_notification_channel_name);
+    nextNotificationId = FOREGROUND_NOTIFICATION_ID + 1;
  }
  @Override
@@ -50,40 +53,41 @@ public class DemoDownloadService extends DownloadService {
  }
  @Override
-  protected Notification getForegroundNotification(TaskState[] taskStates) {
+  protected Notification getForegroundNotification(DownloadState[] downloadStates) {
    return DownloadNotificationUtil.buildProgressNotification(
        /* context= */ this,
-        R.drawable.exo_controls_play,
+        R.drawable.ic_download,
        CHANNEL_ID,
        /* contentIntent= */ null,
        /* message= */ null,
-        taskStates);
+        downloadStates);
  }
  @Override
-  protected void onTaskStateChanged(TaskState taskState) {
+  protected void onDownloadStateChanged(DownloadState downloadState) {
-    if (taskState.action.isRemoveAction) {
+    if (downloadState.action.isRemoveAction) {
      return;
    }
    Notification notification = null;
-    if (taskState.state == TaskState.STATE_COMPLETED) {
+    if (downloadState.state == DownloadState.STATE_COMPLETED) {
      notification =
          DownloadNotificationUtil.buildDownloadCompletedNotification(
              /* context= */ this,
-              R.drawable.exo_controls_play,
+              R.drawable.ic_download_done,
              CHANNEL_ID,
              /* contentIntent= */ null,
-              Util.fromUtf8Bytes(taskState.action.data));
+              Util.fromUtf8Bytes(downloadState.action.data));
-    } else if (taskState.state == TaskState.STATE_FAILED) {
+    } else if (downloadState.state == DownloadState.STATE_FAILED) {
      notification =
          DownloadNotificationUtil.buildDownloadFailedNotification(
              /* context= */ this,
-              R.drawable.exo_controls_play,
+              R.drawable.ic_download_done,
              CHANNEL_ID,
              /* contentIntent= */ null,
-              Util.fromUtf8Bytes(taskState.action.data));
+              Util.fromUtf8Bytes(downloadState.action.data));
+    } else {
+      return;
    }
-    int notificationId = FOREGROUND_NOTIFICATION_ID + 1 + taskState.taskId;
+    NotificationUtil.setNotification(this, nextNotificationId++, notification);
-    NotificationUtil.setNotification(this, notificationId, notification);
  }
 }
--- a/demos/main/src/main/java/com/google/android/exoplayer2/demo/DownloadTracker.java
+++ b/demos/main/src/main/java/com/google/android/exoplayer2/demo/DownloadTracker.java
--- a/demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java
+++ b/demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java
@@ -35,11 +35,11 @@ import android.widget.TextView;
 import android.widget.Toast;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.C.ContentType;
-import com.google.android.exoplayer2.DefaultRenderersFactory;
 import com.google.android.exoplayer2.ExoPlaybackException;
 import com.google.android.exoplayer2.ExoPlayerFactory;
 import com.google.android.exoplayer2.PlaybackPreparer;
 import com.google.android.exoplayer2.Player;
+import com.google.android.exoplayer2.RenderersFactory;
 import com.google.android.exoplayer2.SimpleExoPlayer;
 import com.google.android.exoplayer2.drm.DefaultDrmSessionManager;
 import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
@@ -48,7 +48,6 @@ import com.google.android.exoplayer2.drm.HttpMediaDrmCallback;
 import com.google.android.exoplayer2.drm.UnsupportedDrmException;
 import com.google.android.exoplayer2.mediacodec.MediaCodecRenderer.DecoderInitializationException;
 import com.google.android.exoplayer2.mediacodec.MediaCodecUtil.DecoderQueryException;
-import com.google.android.exoplayer2.offline.FilteringManifestParser;
 import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.BehindLiveWindowException;
 import com.google.android.exoplayer2.source.ConcatenatingMediaSource;
@@ -58,11 +57,8 @@ import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.source.ads.AdsLoader;
 import com.google.android.exoplayer2.source.ads.AdsMediaSource;
 import com.google.android.exoplayer2.source.dash.DashMediaSource;
-import com.google.android.exoplayer2.source.dash.manifest.DashManifestParser;
 import com.google.android.exoplayer2.source.hls.HlsMediaSource;
-import com.google.android.exoplayer2.source.hls.playlist.DefaultHlsPlaylistParserFactory;
 import com.google.android.exoplayer2.source.smoothstreaming.SsMediaSource;
-import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifestParser;
 import com.google.android.exoplayer2.trackselection.AdaptiveTrackSelection;
 import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 import com.google.android.exoplayer2.trackselection.MappingTrackSelector.MappedTrackInfo;
@@ -416,13 +412,8 @@ public class PlayerActivity extends Activity
      boolean preferExtensionDecoders =
          intent.getBooleanExtra(PREFER_EXTENSION_DECODERS_EXTRA, false);
-      @DefaultRenderersFactory.ExtensionRendererMode int extensionRendererMode =
+      RenderersFactory renderersFactory =
-          ((DemoApplication) getApplication()).useExtensionRenderers()
+          ((DemoApplication) getApplication()).buildRenderersFactory(preferExtensionDecoders);
-              ? (preferExtensionDecoders ? DefaultRenderersFactory.EXTENSION_RENDERER_MODE_PREFER
-              : DefaultRenderersFactory.EXTENSION_RENDERER_MODE_ON)
-              : DefaultRenderersFactory.EXTENSION_RENDERER_MODE_OFF;
-      DefaultRenderersFactory renderersFactory =
-          new DefaultRenderersFactory(this, extensionRendererMode);
      trackSelector = new DefaultTrackSelector(trackSelectionFactory);
      trackSelector.setParameters(trackSelectorParameters);
@@ -477,21 +468,19 @@ public class PlayerActivity extends Activity
  @SuppressWarnings("unchecked")
  private MediaSource buildMediaSource(Uri uri, @Nullable String overrideExtension) {
    @ContentType int type = Util.inferContentType(uri, overrideExtension);
+    List<StreamKey> offlineStreamKeys = getOfflineStreamKeys(uri);
    switch (type) {
      case C.TYPE_DASH:
        return new DashMediaSource.Factory(dataSourceFactory)
-            .setManifestParser(
+            .setStreamKeys(offlineStreamKeys)
-                new FilteringManifestParser<>(new DashManifestParser(), getOfflineStreamKeys(uri)))
            .createMediaSource(uri);
      case C.TYPE_SS:
        return new SsMediaSource.Factory(dataSourceFactory)
-            .setManifestParser(
+            .setStreamKeys(offlineStreamKeys)
-                new FilteringManifestParser<>(new SsManifestParser(), getOfflineStreamKeys(uri)))
            .createMediaSource(uri);
      case C.TYPE_HLS:
        return new HlsMediaSource.Factory(dataSourceFactory)
-            .setPlaylistParserFactory(
+            .setStreamKeys(offlineStreamKeys)
-                new DefaultHlsPlaylistParserFactory(getOfflineStreamKeys(uri)))
            .createMediaSource(uri);
      case C.TYPE_OTHER:
        return new ExtractorMediaSource.Factory(dataSourceFactory).createMediaSource(uri);

--- a/demos/main/src/main/java/com/google/android/exoplayer2/demo/SampleChooserActivity.java
+++ b/demos/main/src/main/java/com/google/android/exoplayer2/demo/SampleChooserActivity.java
@@ -37,6 +37,7 @@ import android.widget.ImageButton;
 import android.widget.TextView;
 import android.widget.Toast;
 import com.google.android.exoplayer2.ParserException;
+import com.google.android.exoplayer2.RenderersFactory;
 import com.google.android.exoplayer2.offline.DownloadService;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DataSourceInputStream;
@@ -177,7 +178,11 @@ public class SampleChooserActivity extends Activity
          .show();
    } else {
      UriSample uriSample = (UriSample) sample;
-      downloadTracker.toggleDownload(this, sample.name, uriSample.uri, uriSample.extension);
+      RenderersFactory renderersFactory =
+          ((DemoApplication) getApplication())
+              .buildRenderersFactory(isNonNullAndChecked(preferExtensionDecodersMenuItem));
+      downloadTracker.toggleDownload(
+          this, sample.name, uriSample.uri, uriSample.extension, renderersFactory);
    }
  }

--- a/demos/main/src/main/res/drawable-hdpi/ic_edit.png
+++ b/demos/main/src/main/res/drawable-hdpi/ic_edit.png
--- a/demos/main/src/main/res/drawable-mdpi/ic_edit.png
+++ b/demos/main/src/main/res/drawable-mdpi/ic_edit.png
--- a/demos/main/src/main/res/drawable-xhdpi/ic_edit.png
+++ b/demos/main/src/main/res/drawable-xhdpi/ic_edit.png
--- a/demos/main/src/main/res/drawable-xxhdpi/ic_edit.png
+++ b/demos/main/src/main/res/drawable-xxhdpi/ic_edit.png
--- a/demos/main/src/main/res/drawable-xxxhdpi/ic_edit.png
+++ b/demos/main/src/main/res/drawable-xxxhdpi/ic_edit.png
--- a/demos/main/src/main/res/layout/download_track_item.xml
+++ b/demos/main/src/main/res/layout/download_track_item.xml
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2018 The Android Open Source Project
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+          http://www.apache.org/licenses/LICENSE-2.0
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:paddingStart="12dp"
+    android:paddingEnd="12dp"
+    android:orientation="horizontal"
+    android:gravity="center_vertical">
+  <LinearLayout
+      android:layout_width="0dp"
+      android:layout_height="wrap_content"
+      android:layout_weight="1"
+      android:orientation="vertical">
+    <TextView
+        android:id="@+id/track_title"
+        android:textStyle="bold"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:paddingTop="4dp"/>
+    <TextView
+        android:id="@+id/track_desc"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:paddingBottom="4dp"/>
+  </LinearLayout>
+  <ImageButton
+      android:id="@+id/edit_button"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:background="@android:color/transparent"
+      android:contentDescription="@string/download_edit_track"
+      android:src="@drawable/ic_edit"/>
+</LinearLayout>
--- a/demos/main/src/main/res/layout/start_download_dialog.xml
+++ b/demos/main/src/main/res/layout/start_download_dialog.xml
@@ -13,7 +13,8 @@
     See the License for the specific language governing permissions and
     limitations under the License.
 -->
-<ListView xmlns:android="http://schemas.android.com/apk/res/android"
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    android:id="@+id/representation_list"
+    android:id="@+id/selection_list"
+    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"/>
--- a/demos/main/src/main/res/values/strings.xml
+++ b/demos/main/src/main/res/values/strings.xml
@@ -51,6 +51,10 @@
  <string name="ima_not_loaded">Playing sample without ads, as the IMA extension was not loaded</string>
+  <string name="download_edit_track">Edit selection</string>
+  <string name="download_preparing">Preparing download…</string>
  <string name="download_start_error">Failed to start download</string>
  <string name="download_playlist_unsupported">This demo app does not support downloading playlists</string>

--- a/extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/TimelineQueueEditor.java
+++ b/extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/TimelineQueueEditor.java
@@ -66,13 +66,6 @@ public final class TimelineQueueEditor
   */
  public interface QueueDataAdapter {
    /**
-     * Gets the {@link MediaDescriptionCompat} for a {@code position}.
-     *
-     * @param position The position in the queue for which to provide a description.
-     * @return A {@link MediaDescriptionCompat}.
-     */
-    MediaDescriptionCompat getMediaDescription(int position);
-    /**
     * Adds a {@link MediaDescriptionCompat} at the given {@code position}.
     *
     * @param position The position at which to add.

--- 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
@@ -1693,7 +1693,8 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
   */
  private static boolean codecNeedsEosFlushWorkaround(String name) {
    return (Util.SDK_INT <= 23 && "OMX.google.vorbis.decoder".equals(name))
-        || (Util.SDK_INT <= 19 && "hb2000".equals(Util.DEVICE)
+        || (Util.SDK_INT <= 19
+            && ("hb2000".equals(Util.DEVICE) || "stvm8".equals(Util.DEVICE))
            && ("OMX.amlogic.avc.decoder.awesome".equals(name)
                || "OMX.amlogic.avc.decoder.awesome.secure".equals(name)));
  }

--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadAction.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadAction.java
@@ -77,7 +77,7 @@ public final class DownloadAction {
   *
   * @param type The type of the action.
   * @param uri The URI of the media to be downloaded.
-   * @param keys Keys of tracks to be downloaded. If empty, all tracks will be downloaded.
+   * @param keys Keys of streams to be downloaded. If empty, all streams will be downloaded.
   * @param customCacheKey A custom key for cache indexing, or null.
   * @param data Optional custom data for this action. If {@code null} an empty array will be used.
   */
@@ -108,6 +108,8 @@ public final class DownloadAction {
        /* data= */ null);
  }
+  /** The unique content id. */
+  public final String id;
  /** The type of the action. */
  public final String type;
  /** The uri being downloaded or removed. */
@@ -115,8 +117,8 @@ public final class DownloadAction {
  /** Whether this is a remove action. If false, this is a download action. */
  public final boolean isRemoveAction;
  /**
-   * Keys of tracks to be downloaded. If empty, all tracks will be downloaded. Empty if this action
+   * Keys of streams to be downloaded. If empty, all streams will be downloaded. Empty if this
-   * is a remove action.
+   * action is a remove action.
   */
  public final List<StreamKey> keys;
  /** A custom key for cache indexing, or null. */
@@ -128,8 +130,8 @@ public final class DownloadAction {
   * @param type The type of the action.
   * @param uri The uri being downloaded or removed.
   * @param isRemoveAction Whether this is a remove action. If false, this is a download action.
-   * @param keys Keys of tracks to be downloaded. If empty, all tracks will be downloaded. Empty if
+   * @param keys Keys of streams to be downloaded. If empty, all streams will be downloaded. Empty
-   *     this action is a remove action.
+   *     if this action is a remove action.
   * @param customCacheKey A custom key for cache indexing, or null.
   * @param data Custom data for this action. Null if this action is a remove action.
   */
@@ -140,6 +142,7 @@ public final class DownloadAction {
      List<StreamKey> keys,
      @Nullable String customCacheKey,
      @Nullable byte[] data) {
+    this.id = customCacheKey != null ? customCacheKey : uri.toString();
    this.type = type;
    this.uri = uri;
    this.isRemoveAction = isRemoveAction;
@@ -171,12 +174,10 @@ public final class DownloadAction {
  /** Returns whether this is an action for the same media as the {@code other}. */
  public boolean isSameMedia(DownloadAction other) {
-    return customCacheKey == null
+    return id.equals(other.id);
-        ? other.customCacheKey == null && uri.equals(other.uri)
-        : customCacheKey.equals(other.customCacheKey);
  }
-  /** Returns keys of tracks to be downloaded. */
+  /** Returns keys of streams to be downloaded. */
  public List<StreamKey> getKeys() {
    return keys;
  }
@@ -187,7 +188,8 @@ public final class DownloadAction {
      return false;
    }
    DownloadAction that = (DownloadAction) o;
-    return type.equals(that.type)
+    return id.equals(that.id)
+        && type.equals(that.type)
        && uri.equals(that.uri)
        && isRemoveAction == that.isRemoveAction
        && keys.equals(that.keys)
@@ -198,6 +200,7 @@ public final class DownloadAction {
  @Override
  public final int hashCode() {
    int result = type.hashCode();
+    result = 31 * result + id.hashCode();
    result = 31 * result + uri.hashCode();
    result = 31 * result + (isRemoveAction ? 1 : 0);
    result = 31 * result + keys.hashCode();

--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadActionUtil.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadActionUtil.java
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.android.exoplayer2.offline;
+import com.google.android.exoplayer2.util.Assertions;
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.HashSet;
+/** {@link DownloadAction} related utility methods. */
+public class DownloadActionUtil {
+  private DownloadActionUtil() {}
+  /**
+   * Merge {@link DownloadAction}s in {@code actionQueue} to minimum number of actions.
+   *
+   * <p>All actions must have the same type and must be for the same media.
+   *
+   * @param actionQueue Queue of actions. Must not be empty.
+   * @return The first action in the queue.
+   */
+  public static DownloadAction mergeActions(ArrayDeque<DownloadAction> actionQueue) {
+    DownloadAction removeAction = null;
+    DownloadAction downloadAction = null;
+    HashSet<StreamKey> keys = new HashSet<>();
+    boolean downloadAllTracks = false;
+    DownloadAction firstAction = Assertions.checkNotNull(actionQueue.peek());
+    while (!actionQueue.isEmpty()) {
+      DownloadAction action = actionQueue.remove();
+      Assertions.checkState(action.type.equals(firstAction.type));
+      Assertions.checkState(action.isSameMedia(firstAction));
+      if (action.isRemoveAction) {
+        removeAction = action;
+        downloadAction = null;
+        keys.clear();
+        downloadAllTracks = false;
+      } else {
+        if (!downloadAllTracks) {
+          if (action.keys.isEmpty()) {
+            downloadAllTracks = true;
+            keys.clear();
+          } else {
+            keys.addAll(action.keys);
+          }
+        }
+        downloadAction = action;
+      }
+    }
+    if (removeAction != null) {
+      actionQueue.add(removeAction);
+    }
+    if (downloadAction != null) {
+      actionQueue.add(
+          DownloadAction.createDownloadAction(
+              downloadAction.type,
+              downloadAction.uri,
+              new ArrayList<>(keys),
+              downloadAction.customCacheKey,
+              downloadAction.data));
+    }
+    return Assertions.checkNotNull(actionQueue.peek());
+  }
+}
--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadHelper.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadHelper.java
--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadManager.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadManager.java
--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadService.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/DownloadService.java
@@ -24,7 +24,7 @@ import android.os.IBinder;
 import android.os.Looper;
 import android.support.annotation.Nullable;
 import android.support.annotation.StringRes;
-import com.google.android.exoplayer2.offline.DownloadManager.TaskState;
+import com.google.android.exoplayer2.offline.DownloadManager.DownloadState;
 import com.google.android.exoplayer2.scheduler.Requirements;
 import com.google.android.exoplayer2.scheduler.RequirementsWatcher;
 import com.google.android.exoplayer2.scheduler.Scheduler;
@@ -71,9 +71,9 @@ public abstract class DownloadService extends Service {
  private static final String TAG = "DownloadService";
  private static final boolean DEBUG = false;
-  // Keep the requirements helper for each DownloadService as long as there are tasks (and the
+  // Keep the requirements helper for each DownloadService as long as there are downloads (and the
-  // process is running). This allows tasks to resume when there's no scheduler. It may also allow
+  // process is running). This allows downloads to resume when there's no scheduler. It may also
-  // tasks the resume more quickly than when relying on the scheduler alone.
+  // allow downloads the resume more quickly than when relying on the scheduler alone.
  private static final HashMap<Class<? extends DownloadService>, RequirementsHelper>
      requirementsHelpers = new HashMap<>();
  private static final Requirements DEFAULT_REQUIREMENTS =
@@ -99,7 +99,7 @@ public abstract class DownloadService extends Service {
   * <p>If {@code foregroundNotificationId} isn't {@link #FOREGROUND_NOTIFICATION_ID_NONE} (value
   * {@value #FOREGROUND_NOTIFICATION_ID_NONE}) the service runs in the foreground with {@link
   * #DEFAULT_FOREGROUND_NOTIFICATION_UPDATE_INTERVAL}. In that case {@link
-   * #getForegroundNotification(TaskState[])} should be overridden in the subclass.
+   * #getForegroundNotification(DownloadState[])} should be overridden in the subclass.
   *
   * @param foregroundNotificationId The notification id for the foreground notification, or {@link
   *     #FOREGROUND_NOTIFICATION_ID_NONE} (value {@value #FOREGROUND_NOTIFICATION_ID_NONE})
@@ -110,7 +110,7 @@ public abstract class DownloadService extends Service {
  /**
   * Creates a DownloadService which will run in the foreground. {@link
-   * #getForegroundNotification(TaskState[])} should be overridden in the subclass.
+   * #getForegroundNotification(DownloadState[])} should be overridden in the subclass.
   *
   * @param foregroundNotificationId The notification id for the foreground notification, must not
   *     be 0.
@@ -128,7 +128,7 @@ public abstract class DownloadService extends Service {
  /**
   * Creates a DownloadService which will run in the foreground. {@link
-   * #getForegroundNotification(TaskState[])} should be overridden in the subclass.
+   * #getForegroundNotification(DownloadState[])} should be overridden in the subclass.
   *
   * @param foregroundNotificationId The notification id for the foreground notification. Must not
   *     be 0.
@@ -338,29 +338,29 @@ public abstract class DownloadService extends Service {
   *
   * <p>Returns a notification to be displayed when this service running in the foreground.
   *
-   * <p>This method is called when there is a task state change and periodically while there are
+   * <p>This method is called when there is a download state change and periodically while there are
-   * active tasks. The periodic update interval can be set using {@link #DownloadService(int,
+   * active downloads. The periodic update interval can be set using {@link #DownloadService(int,
   * long)}.
   *
   * <p>On API level 26 and above, this method may also be called just before the service stops,
-   * with an empty {@code taskStates} array. The returned notification is used to satisfy system
+   * with an empty {@code downloadStates} array. The returned notification is used to satisfy system
   * requirements for foreground services.
   *
-   * @param taskStates The states of all current tasks.
+   * @param downloadStates The states of all current downloads.
   * @return The foreground notification to display.
   */
-  protected Notification getForegroundNotification(TaskState[] taskStates) {
+  protected Notification getForegroundNotification(DownloadState[] downloadStates) {
    throw new IllegalStateException(
        getClass().getName()
            + " is started in the foreground but getForegroundNotification() is not implemented.");
  }
  /**
-   * Called when the state of a task changes.
+   * Called when the state of a download changes.
   *
-   * @param taskState The state of the task.
+   * @param downloadState The state of the download.
   */
-  protected void onTaskStateChanged(TaskState taskState) {
+  protected void onDownloadStateChanged(DownloadState downloadState) {
    // Do nothing.
  }
@@ -428,10 +428,11 @@ public abstract class DownloadService extends Service {
    }
    @Override
-    public void onTaskStateChanged(DownloadManager downloadManager, TaskState taskState) {
+    public void onDownloadStateChanged(
-      DownloadService.this.onTaskStateChanged(taskState);
+        DownloadManager downloadManager, DownloadState downloadState) {
+      DownloadService.this.onDownloadStateChanged(downloadState);
      if (foregroundNotificationUpdater != null) {
-        if (taskState.state == TaskState.STATE_STARTED) {
+        if (downloadState.state == DownloadState.STATE_STARTED) {
          foregroundNotificationUpdater.startPeriodicUpdates();
        } else {
          foregroundNotificationUpdater.update();
@@ -471,8 +472,8 @@ public abstract class DownloadService extends Service {
    }
    public void update() {
-      TaskState[] taskStates = downloadManager.getAllTaskStates();
+      DownloadState[] downloadStates = downloadManager.getAllDownloadStates();
-      startForeground(notificationId, getForegroundNotification(taskStates));
+      startForeground(notificationId, getForegroundNotification(downloadStates));
      notificationDisplayed = true;
      if (periodicUpdatesStarted) {
        handler.removeCallbacks(this);

--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/FilteringManifestParser.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/FilteringManifestParser.java
@@ -16,22 +16,27 @@
 package com.google.android.exoplayer2.offline;
 import android.net.Uri;
+import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.upstream.ParsingLoadable.Parser;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
-/** A manifest parser that includes only the streams identified by the given stream keys. */
+/**
+ * A manifest parser that includes only the streams identified by the given stream keys.
+ *
+ * @param <T> The {@link FilterableManifest} type.
+ */
 public final class FilteringManifestParser<T extends FilterableManifest<T>> implements Parser<T> {
-  private final Parser<T> parser;
+  private final Parser<? extends T> parser;
-  private final List<StreamKey> streamKeys;
+  @Nullable private final List<StreamKey> streamKeys;
  /**
   * @param parser A parser for the manifest that will be filtered.
   * @param streamKeys The stream keys. If null or empty then filtering will not occur.
   */
-  public FilteringManifestParser(Parser<T> parser, List<StreamKey> streamKeys) {
+  public FilteringManifestParser(Parser<? extends T> parser, @Nullable List<StreamKey> streamKeys) {
    this.parser = parser;
    this.streamKeys = streamKeys;
  }

--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/ProgressiveDownloadHelper.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/ProgressiveDownloadHelper.java
@@ -17,19 +17,35 @@ package com.google.android.exoplayer2.offline;
 import android.net.Uri;
 import android.support.annotation.Nullable;
+import com.google.android.exoplayer2.Renderer;
 import com.google.android.exoplayer2.source.TrackGroupArray;
-import java.util.Collections;
-import java.util.List;
 /** A {@link DownloadHelper} for progressive streams. */
 public final class ProgressiveDownloadHelper extends DownloadHelper<Void> {
+  /**
+   * Creates download helper for progressive streams.
+   *
+   * @param uri The stream {@link Uri}.
+   */
  public ProgressiveDownloadHelper(Uri uri) {
-    this(uri, null);
+    this(uri, /* cacheKey= */ null);
  }
-  public ProgressiveDownloadHelper(Uri uri, @Nullable String customCacheKey) {
+  /**
-    super(DownloadAction.TYPE_PROGRESSIVE, uri, customCacheKey);
+   * Creates download helper for progressive streams.
+   *
+   * @param uri The stream {@link Uri}.
+   * @param cacheKey An optional cache key.
+   */
+  public ProgressiveDownloadHelper(Uri uri, @Nullable String cacheKey) {
+    super(
+        DownloadAction.TYPE_PROGRESSIVE,
+        uri,
+        cacheKey,
+        DownloadHelper.DEFAULT_TRACK_SELECTOR_PARAMETERS,
+        (handler, videoListener, audioListener, metadata, text, drm) -> new Renderer[0],
+        /* drmSessionManager= */ null);
  }
  @Override
@@ -43,7 +59,8 @@ public final class ProgressiveDownloadHelper extends DownloadHelper<Void> {
  }
  @Override
-  protected List<StreamKey> toStreamKeys(List<TrackKey> trackKeys) {
+  protected StreamKey toStreamKey(
-    return Collections.emptyList();
+      int periodIndex, int trackGroupIndex, int trackIndexInTrackGroup) {
+    return new StreamKey(periodIndex, trackGroupIndex, trackIndexInTrackGroup);
  }
 }
--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/StreamKey.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/StreamKey.java
@@ -19,8 +19,11 @@ import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 /**
- * Identifies a given track by the index of the containing period, the index of the containing group
+ * A key for a subset of media which can be separately loaded (a "stream").
- * within the period, and the index of the track within the group.
+ *
+ * <p>The stream key consists of a period index, a group index within the period and a track index
+ * within the group. The interpretation of these indices depends on the type of media for which the
+ * stream key is used.
 */
 public final class StreamKey implements Comparable<StreamKey> {

--- a/library/core/src/main/java/com/google/android/exoplayer2/offline/TrackKey.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/offline/TrackKey.java
-/*
- * Copyright (C) 2018 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.google.android.exoplayer2.offline;
-/**
- * Identifies a given track by the index of the containing period, the index of the containing group
- * within the period, and the index of the track within the group.
- */
-public final class TrackKey {
-  /** The period index. */
-  public final int periodIndex;
-  /** The group index. */
-  public final int groupIndex;
-  /** The track index. */
-  public final int trackIndex;
-  /**
-   * @param periodIndex The period index.
-   * @param groupIndex The group index.
-   * @param trackIndex The track index.
-   */
-  public TrackKey(int periodIndex, int groupIndex, int trackIndex) {
-    this.periodIndex = periodIndex;
-    this.groupIndex = groupIndex;
-    this.trackIndex = trackIndex;
-  }
-}
--- a/library/core/src/main/java/com/google/android/exoplayer2/source/ConcatenatingMediaSource.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/source/ConcatenatingMediaSource.java
@@ -826,7 +826,7 @@ public class ConcatenatingMediaSource extends CompositeMediaSource<MediaSourceHo
    public MediaSourceHolder(MediaSource mediaSource) {
      this.mediaSource = mediaSource;
-      this.timeline = new DeferredTimeline();
+      this.timeline = DeferredTimeline.createWithDummyTimeline(mediaSource.getTag());
      this.activeMediaPeriods = new ArrayList<>();
      this.uid = new Object();
    }
@@ -951,11 +951,19 @@ public class ConcatenatingMediaSource extends CompositeMediaSource<MediaSourceHo
  private static final class DeferredTimeline extends ForwardingTimeline {
    private static final Object DUMMY_ID = new Object();
-    private static final DummyTimeline DUMMY_TIMELINE = new DummyTimeline();
    private final Object replacedId;
    /**
+     * Returns an instance with a dummy timeline using the provided window tag.
+     *
+     * @param windowTag A window tag.
+     */
+    public static DeferredTimeline createWithDummyTimeline(@Nullable Object windowTag) {
+      return new DeferredTimeline(new DummyTimeline(windowTag), DUMMY_ID);
+    }
+    /**
     * Returns an instance with a real timeline, replacing the provided period ID with the already
     * assigned dummy period ID.
     *
@@ -968,11 +976,6 @@ public class ConcatenatingMediaSource extends CompositeMediaSource<MediaSourceHo
      return new DeferredTimeline(timeline, firstPeriodUid);
    }
-    /** Creates deferred timeline exposing a {@link DummyTimeline}. */
-    public DeferredTimeline() {
-      this(DUMMY_TIMELINE, DUMMY_ID);
-    }
    private DeferredTimeline(Timeline timeline, Object replacedId) {
      super(timeline);
      this.replacedId = replacedId;
@@ -1016,6 +1019,12 @@ public class ConcatenatingMediaSource extends CompositeMediaSource<MediaSourceHo
  /** Dummy placeholder timeline with one dynamic window with a period of indeterminate duration. */
  private static final class DummyTimeline extends Timeline {
+    @Nullable private final Object tag;
+    public DummyTimeline(@Nullable Object tag) {
+      this.tag = tag;
+    }
    @Override
    public int getWindowCount() {
      return 1;
@@ -1025,7 +1034,7 @@ public class ConcatenatingMediaSource extends CompositeMediaSource<MediaSourceHo
    public Window getWindow(
        int windowIndex, Window window, boolean setTag, long defaultPositionProjectionUs) {
      return window.set(
-          /* tag= */ null,
+          tag,
          /* presentationStartTimeMs= */ C.TIME_UNSET,
          /* windowStartTimeMs= */ C.TIME_UNSET,
          /* isSeekable= */ false,

--- a/library/core/src/main/java/com/google/android/exoplayer2/source/MediaPeriod.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/source/MediaPeriod.java
@@ -19,8 +19,11 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.SeekParameters;
 import com.google.android.exoplayer2.Timeline;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.trackselection.TrackSelection;
 import java.io.IOException;
+import java.util.Collections;
+import java.util.List;
 import org.checkerframework.checker.nullness.compatqual.NullableType;
 /**
@@ -84,6 +87,22 @@ public interface MediaPeriod extends SequenceableLoader {
  TrackGroupArray getTrackGroups();
  /**
+   * Returns a list of {@link StreamKey stream keys} which allow to filter the media in this period
+   * to load only the parts needed to play the provided {@link TrackSelection}.
+   *
+   * <p>This method is only called after the period has been prepared.
+   *
+   * @param trackSelection The {@link TrackSelection} describing the tracks for which stream keys
+   *     are requested.
+   * @return The corresponding {@link StreamKey stream keys} for the selected tracks, or an empty
+   *     list if filtering is not possible and the entire media needs to be loaded to play the
+   *     selected tracks.
+   */
+  default List<StreamKey> getStreamKeys(TrackSelection trackSelection) {
+    return Collections.emptyList();
+  }
+  /**
   * Performs a track selection.
   *
   * <p>The call receives track {@code selections} for each renderer, {@code mayRetainStreamFlags}

--- a/library/core/src/main/java/com/google/android/exoplayer2/text/ttml/TtmlDecoder.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/text/ttml/TtmlDecoder.java
--- a/library/core/src/main/java/com/google/android/exoplayer2/text/ttml/TtmlNode.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/text/ttml/TtmlNode.java
@@ -15,7 +15,12 @@
 */
 package com.google.android.exoplayer2.text.ttml;
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.support.annotation.Nullable;
 import android.text.SpannableStringBuilder;
+import android.util.Base64;
+import android.util.Pair;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.text.Cue;
 import com.google.android.exoplayer2.util.Assertions;
@@ -44,9 +49,9 @@ import java.util.TreeSet;
  public static final String TAG_LAYOUT = "layout";
  public static final String TAG_REGION = "region";
  public static final String TAG_METADATA = "metadata";
-  public static final String TAG_SMPTE_IMAGE = "smpte:image";
+  public static final String TAG_IMAGE = "image";
-  public static final String TAG_SMPTE_DATA = "smpte:data";
+  public static final String TAG_DATA = "data";
-  public static final String TAG_SMPTE_INFORMATION = "smpte:information";
+  public static final String TAG_INFORMATION = "information";
  public static final String ANONYMOUS_REGION_ID = "";
  public static final String ATTR_ID = "id";
@@ -75,34 +80,57 @@ import java.util.TreeSet;
  public static final String START = "start";
  public static final String END = "end";
-  public final String tag;
+  @Nullable public final String tag;
-  public final String text;
+  @Nullable public final String text;
  public final boolean isTextNode;
  public final long startTimeUs;
  public final long endTimeUs;
-  public final TtmlStyle style;
+  @Nullable public final TtmlStyle style;
+  @Nullable private final String[] styleIds;
  public final String regionId;
+  @Nullable public final String imageId;
-  private final String[] styleIds;
  private final HashMap<String, Integer> nodeStartsByRegion;
  private final HashMap<String, Integer> nodeEndsByRegion;
  private List<TtmlNode> children;
  public static TtmlNode buildTextNode(String text) {
-    return new TtmlNode(null, TtmlRenderUtil.applyTextElementSpacePolicy(text), C.TIME_UNSET,
+    return new TtmlNode(
-        C.TIME_UNSET, null, null, ANONYMOUS_REGION_ID);
+        /* tag= */ null,
+        TtmlRenderUtil.applyTextElementSpacePolicy(text),
+        /* startTimeUs= */ C.TIME_UNSET,
+        /* endTimeUs= */ C.TIME_UNSET,
+        /* style= */ null,
+        /* styleIds= */ null,
+        ANONYMOUS_REGION_ID,
+        /* imageId= */ null);
  }
-  public static TtmlNode buildNode(String tag, long startTimeUs, long endTimeUs,
+  public static TtmlNode buildNode(
-      TtmlStyle style, String[] styleIds, String regionId) {
+      @Nullable String tag,
-    return new TtmlNode(tag, null, startTimeUs, endTimeUs, style, styleIds, regionId);
+      long startTimeUs,
+      long endTimeUs,
+      @Nullable TtmlStyle style,
+      @Nullable String[] styleIds,
+      String regionId,
+      @Nullable String imageId) {
+    return new TtmlNode(
+        tag, /* text= */ null, startTimeUs, endTimeUs, style, styleIds, regionId, imageId);
  }
-  private TtmlNode(String tag, String text, long startTimeUs, long endTimeUs,
+  private TtmlNode(
-      TtmlStyle style, String[] styleIds, String regionId) {
+      @Nullable String tag,
+      @Nullable String text,
+      long startTimeUs,
+      long endTimeUs,
+      @Nullable TtmlStyle style,
+      @Nullable String[] styleIds,
+      String regionId,
+      @Nullable String imageId) {
    this.tag = tag;
    this.text = text;
+    this.imageId = imageId;
    this.style = style;
    this.styleIds = styleIds;
    this.isTextNode = text != null;
@@ -151,7 +179,8 @@ import java.util.TreeSet;
  private void getEventTimes(TreeSet<Long> out, boolean descendsPNode) {
    boolean isPNode = TAG_P.equals(tag);
-    if (descendsPNode || isPNode) {
+    boolean isDivNode = TAG_DIV.equals(tag);
+    if (descendsPNode || isPNode || (isDivNode && imageId != null)) {
      if (startTimeUs != C.TIME_UNSET) {
        out.add(startTimeUs);
      }
@@ -171,13 +200,46 @@ import java.util.TreeSet;
    return styleIds;
  }
-  public List<Cue> getCues(long timeUs, Map<String, TtmlStyle> globalStyles,
+  public List<Cue> getCues(
-      Map<String, TtmlRegion> regionMap) {
+      long timeUs,
-    TreeMap<String, SpannableStringBuilder> regionOutputs = new TreeMap<>();
+      Map<String, TtmlStyle> globalStyles,
-    traverseForText(timeUs, false, regionId, regionOutputs);
+      Map<String, TtmlRegion> regionMap,
-    traverseForStyle(timeUs, globalStyles, regionOutputs);
+      Map<String, String> imageMap) {
+    List<Pair<String, String>> regionImageOutputs = new ArrayList<>();
+    traverseForImage(timeUs, regionId, regionImageOutputs);
+    TreeMap<String, SpannableStringBuilder> regionTextOutputs = new TreeMap<>();
+    traverseForText(timeUs, false, regionId, regionTextOutputs);
+    traverseForStyle(timeUs, globalStyles, regionTextOutputs);
    List<Cue> cues = new ArrayList<>();
-    for (Entry<String, SpannableStringBuilder> entry : regionOutputs.entrySet()) {
+    // Create image based cues.
+    for (Pair<String, String> regionImagePair : regionImageOutputs) {
+      String encodedBitmapData = imageMap.get(regionImagePair.second);
+      if (encodedBitmapData == null) {
+        // Image reference points to an invalid image. Do nothing.
+        continue;
+      }
+      byte[] bitmapData = Base64.decode(encodedBitmapData, Base64.DEFAULT);
+      Bitmap bitmap = BitmapFactory.decodeByteArray(bitmapData, /* offset= */ 0, bitmapData.length);
+      TtmlRegion region = regionMap.get(regionImagePair.first);
+      cues.add(
+          new Cue(
+              bitmap,
+              region.position,
+              Cue.ANCHOR_TYPE_MIDDLE,
+              region.line,
+              region.lineAnchor,
+              region.width,
+              /* height= */ Cue.DIMEN_UNSET));
+    }
+    // Create text based cues.
+    for (Entry<String, SpannableStringBuilder> entry : regionTextOutputs.entrySet()) {
      TtmlRegion region = regionMap.get(entry.getKey());
      cues.add(
          new Cue(
@@ -192,9 +254,22 @@ import java.util.TreeSet;
              region.textSizeType,
              region.textSize));
    }
    return cues;
  }
+  private void traverseForImage(
+      long timeUs, String inheritedRegion, List<Pair<String, String>> regionImageList) {
+    String resolvedRegionId = ANONYMOUS_REGION_ID.equals(regionId) ? inheritedRegion : regionId;
+    if (isActive(timeUs) && TAG_DIV.equals(tag) && imageId != null) {
+      regionImageList.add(new Pair<>(resolvedRegionId, imageId));
+      return;
+    }
+    for (int i = 0; i < getChildCount(); ++i) {
+      getChild(i).traverseForImage(timeUs, resolvedRegionId, regionImageList);
+    }
+  }
  private void traverseForText(
      long timeUs,
      boolean descendsPNode,

--- a/library/core/src/main/java/com/google/android/exoplayer2/text/ttml/TtmlSubtitle.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/text/ttml/TtmlSubtitle.java
@@ -33,11 +33,16 @@ import java.util.Map;
  private final long[] eventTimesUs;
  private final Map<String, TtmlStyle> globalStyles;
  private final Map<String, TtmlRegion> regionMap;
+  private final Map<String, String> imageMap;
-  public TtmlSubtitle(TtmlNode root, Map<String, TtmlStyle> globalStyles,
+  public TtmlSubtitle(
-      Map<String, TtmlRegion> regionMap) {
+      TtmlNode root,
+      Map<String, TtmlStyle> globalStyles,
+      Map<String, TtmlRegion> regionMap,
+      Map<String, String> imageMap) {
    this.root = root;
    this.regionMap = regionMap;
+    this.imageMap = imageMap;
    this.globalStyles =
        globalStyles != null ? Collections.unmodifiableMap(globalStyles) : Collections.emptyMap();
    this.eventTimesUs = root.getEventTimesUs();
@@ -66,7 +71,7 @@ import java.util.Map;
  @Override
  public List<Cue> getCues(long timeUs) {
-    return root.getCues(timeUs, globalStyles, regionMap);
+    return root.getCues(timeUs, globalStyles, regionMap, imageMap);
  }
  @VisibleForTesting

--- a/library/core/src/main/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelection.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelection.java
@@ -227,27 +227,6 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
    }
    @Override
-    public AdaptiveTrackSelection createTrackSelection(
-        TrackGroup group, BandwidthMeter bandwidthMeter, int... tracks) {
-      if (this.bandwidthMeter != null) {
-        bandwidthMeter = this.bandwidthMeter;
-      }
-      AdaptiveTrackSelection adaptiveTrackSelection =
-          new AdaptiveTrackSelection(
-              group,
-              tracks,
-              new DefaultBandwidthProvider(bandwidthMeter, bandwidthFraction),
-              minDurationForQualityIncreaseMs,
-              maxDurationForQualityDecreaseMs,
-              minDurationToRetainAfterDiscardMs,
-              bufferedFractionToLiveEdgeForQualityIncrease,
-              minTimeBetweenBufferReevaluationMs,
-              clock);
-      adaptiveTrackSelection.experimental_setTrackBitrateEstimator(trackBitrateEstimator);
-      return adaptiveTrackSelection;
-    }
-    @Override
    public @NullableType TrackSelection[] createTrackSelections(
        @NullableType Definition[] definitions, BandwidthMeter bandwidthMeter) {
      TrackSelection[] selections = new TrackSelection[definitions.length];
@@ -259,8 +238,9 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
          continue;
        }
        if (definition.tracks.length > 1) {
-          selections[i] = createTrackSelection(definition.group, bandwidthMeter, definition.tracks);
+          adaptiveSelection =
-          adaptiveSelection = (AdaptiveTrackSelection) selections[i];
+              createAdaptiveTrackSelection(definition.group, bandwidthMeter, definition.tracks);
+          selections[i] = adaptiveSelection;
        } else {
          selections[i] = new FixedTrackSelection(definition.group, definition.tracks[0]);
          int trackBitrate = definition.group.getFormat(definition.tracks[0]).bitrate;
@@ -274,6 +254,26 @@ public class AdaptiveTrackSelection extends BaseTrackSelection {
      }
      return selections;
    }
+    private AdaptiveTrackSelection createAdaptiveTrackSelection(
+        TrackGroup group, BandwidthMeter bandwidthMeter, int[] tracks) {
+      if (this.bandwidthMeter != null) {
+        bandwidthMeter = this.bandwidthMeter;
+      }
+      AdaptiveTrackSelection adaptiveTrackSelection =
+          new AdaptiveTrackSelection(
+              group,
+              tracks,
+              new DefaultBandwidthProvider(bandwidthMeter, bandwidthFraction),
+              minDurationForQualityIncreaseMs,
+              maxDurationForQualityDecreaseMs,
+              minDurationToRetainAfterDiscardMs,
+              bufferedFractionToLiveEdgeForQualityIncrease,
+              minTimeBetweenBufferReevaluationMs,
+              clock);
+      adaptiveTrackSelection.experimental_setTrackBitrateEstimator(trackBitrateEstimator);
+      return adaptiveTrackSelection;
+    }
  }
  public static final int DEFAULT_MIN_DURATION_FOR_QUALITY_INCREASE_MS = 10000;

--- a/library/core/src/main/java/com/google/android/exoplayer2/trackselection/BufferSizeAdaptationBuilder.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/trackselection/BufferSizeAdaptationBuilder.java
@@ -24,12 +24,14 @@ import com.google.android.exoplayer2.LoadControl;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.chunk.MediaChunk;
 import com.google.android.exoplayer2.source.chunk.MediaChunkIterator;
+import com.google.android.exoplayer2.trackselection.TrackSelection.Definition;
 import com.google.android.exoplayer2.upstream.BandwidthMeter;
 import com.google.android.exoplayer2.upstream.DefaultAllocator;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Clock;
 import com.google.android.exoplayer2.util.PriorityTaskManager;
 import java.util.List;
+import org.checkerframework.checker.nullness.compatqual.NullableType;
 /**
 * Builder for a {@link TrackSelection.Factory} and {@link LoadControl} that implement buffer size
@@ -273,19 +275,22 @@ public final class BufferSizeAdaptationBuilder {
    TrackSelection.Factory trackSelectionFactory =
        new TrackSelection.Factory() {
          @Override
-          public TrackSelection createTrackSelection(
+          public @NullableType TrackSelection[] createTrackSelections(
-              TrackGroup group, BandwidthMeter bandwidthMeter, int... tracks) {
+              @NullableType Definition[] definitions, BandwidthMeter bandwidthMeter) {
-            return new BufferSizeAdaptiveTrackSelection(
+            return TrackSelectionUtil.createTrackSelectionsForDefinitions(
-                group,
+                definitions,
-                tracks,
+                definition ->
-                bandwidthMeter,
+                    new BufferSizeAdaptiveTrackSelection(
-                minBufferMs,
+                        definition.group,
-                maxBufferMs,
+                        definition.tracks,
-                hysteresisBufferMs,
+                        bandwidthMeter,
-                startUpBandwidthFraction,
+                        minBufferMs,
-                startUpMinBufferForQualityIncreaseMs,
+                        maxBufferMs,
-                dynamicFormatFilter,
+                        hysteresisBufferMs,
-                clock);
+                        startUpBandwidthFraction,
+                        startUpMinBufferForQualityIncreaseMs,
+                        dynamicFormatFilter,
+                        clock));
          }
        };

--- a/library/core/src/main/java/com/google/android/exoplayer2/trackselection/FixedTrackSelection.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/trackselection/FixedTrackSelection.java
@@ -21,8 +21,8 @@ import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.chunk.MediaChunk;
 import com.google.android.exoplayer2.source.chunk.MediaChunkIterator;
 import com.google.android.exoplayer2.upstream.BandwidthMeter;
-import com.google.android.exoplayer2.util.Assertions;
 import java.util.List;
+import org.checkerframework.checker.nullness.compatqual.NullableType;
 /**
 * A {@link TrackSelection} consisting of a single track.
@@ -56,10 +56,12 @@ public final class FixedTrackSelection extends BaseTrackSelection {
    }
    @Override
-    public FixedTrackSelection createTrackSelection(
+    public @NullableType TrackSelection[] createTrackSelections(
-        TrackGroup group, BandwidthMeter bandwidthMeter, int... tracks) {
+        @NullableType Definition[] definitions, BandwidthMeter bandwidthMeter) {
-      Assertions.checkArgument(tracks.length == 1);
+      return TrackSelectionUtil.createTrackSelectionsForDefinitions(
-      return new FixedTrackSelection(group, tracks[0], reason, data);
+          definitions,
+          definition ->
+              new FixedTrackSelection(definition.group, definition.tracks[0], reason, data));
    }
  }

--- a/library/core/src/main/java/com/google/android/exoplayer2/trackselection/RandomTrackSelection.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/trackselection/RandomTrackSelection.java
@@ -24,6 +24,7 @@ import com.google.android.exoplayer2.source.chunk.MediaChunkIterator;
 import com.google.android.exoplayer2.upstream.BandwidthMeter;
 import java.util.List;
 import java.util.Random;
+import org.checkerframework.checker.nullness.compatqual.NullableType;
 /**
 * A {@link TrackSelection} whose selected track is updated randomly.
@@ -49,9 +50,11 @@ public final class RandomTrackSelection extends BaseTrackSelection {
    }
    @Override
-    public RandomTrackSelection createTrackSelection(
+    public @NullableType TrackSelection[] createTrackSelections(
-        TrackGroup group, BandwidthMeter bandwidthMeter, int... tracks) {
+        @NullableType Definition[] definitions, BandwidthMeter bandwidthMeter) {
-      return new RandomTrackSelection(group, tracks, random);
+      return TrackSelectionUtil.createTrackSelectionsForDefinitions(
+          definitions,
+          definition -> new RandomTrackSelection(definition.group, definition.tracks, random));
    }
  }

--- a/library/core/src/main/java/com/google/android/exoplayer2/trackselection/TrackSelection.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/trackselection/TrackSelection.java
@@ -21,8 +21,8 @@ import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.chunk.MediaChunk;
 import com.google.android.exoplayer2.source.chunk.MediaChunkIterator;
+import com.google.android.exoplayer2.trackselection.TrackSelectionUtil.AdaptiveTrackSelectionFactory;
 import com.google.android.exoplayer2.upstream.BandwidthMeter;
-import com.google.android.exoplayer2.util.Assertions;
 import java.util.List;
 import org.checkerframework.checker.nullness.compatqual.NullableType;
@@ -61,42 +61,31 @@ public interface TrackSelection {
  interface Factory {
    /**
-     * Creates a new selection.
+     * @deprecated Implement {@link #createTrackSelections(Definition[], BandwidthMeter)} instead.
-     *
+     *     Calling {@link TrackSelectionUtil#createTrackSelectionsForDefinitions(Definition[],
-     * @param group The {@link TrackGroup}. Must not be null.
+     *     AdaptiveTrackSelectionFactory)} helps to create a single adaptive track selection in the
-     * @param bandwidthMeter A {@link BandwidthMeter} which can be used to select tracks.
+     *     same way as using this deprecated method.
-     * @param tracks The indices of the selected tracks within the {@link TrackGroup}. Must not be
-     *     null or empty. May be in any order.
-     * @return The created selection.
     */
-    TrackSelection createTrackSelection(
+    @Deprecated
-        TrackGroup group, BandwidthMeter bandwidthMeter, int... tracks);
+    default TrackSelection createTrackSelection(
+        TrackGroup group, BandwidthMeter bandwidthMeter, int... tracks) {
+      throw new UnsupportedOperationException();
+    }
    /**
     * Creates a new selection for each {@link Definition}.
     *
     * @param definitions A {@link Definition} array. May include null values.
     * @param bandwidthMeter A {@link BandwidthMeter} which can be used to select tracks.
-     * @return The created selections. For null entries in {@code definitions} returns null values.
+     * @return The created selections. Must have the same length as {@code definitions} and may
+     *     include null values.
     */
+    @SuppressWarnings("deprecation")
    default @NullableType TrackSelection[] createTrackSelections(
        @NullableType Definition[] definitions, BandwidthMeter bandwidthMeter) {
-      TrackSelection[] selections = new TrackSelection[definitions.length];
+      return TrackSelectionUtil.createTrackSelectionsForDefinitions(
-      boolean createdAdaptiveTrackSelection = false;
+          definitions,
-      for (int i = 0; i < definitions.length; i++) {
+          definition -> createTrackSelection(definition.group, bandwidthMeter, definition.tracks));
-        Definition definition = definitions[i];
-        if (definition == null) {
-          continue;
-        }
-        if (definition.tracks.length > 1) {
-          Assertions.checkState(!createdAdaptiveTrackSelection);
-          createdAdaptiveTrackSelection = true;
-          selections[i] = createTrackSelection(definition.group, bandwidthMeter, definition.tracks);
-        } else {
-          selections[i] = new FixedTrackSelection(definition.group, definition.tracks[0]);
-        }
-      }
-      return selections;
    }
  }

--- a/library/core/src/main/java/com/google/android/exoplayer2/trackselection/TrackSelectionUtil.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/trackselection/TrackSelectionUtil.java
@@ -22,15 +22,59 @@ import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.source.chunk.MediaChunk;
 import com.google.android.exoplayer2.source.chunk.MediaChunkIterator;
 import com.google.android.exoplayer2.source.chunk.MediaChunkListIterator;
+import com.google.android.exoplayer2.trackselection.TrackSelection.Definition;
 import com.google.android.exoplayer2.util.Assertions;
 import java.util.Arrays;
 import java.util.List;
+import org.checkerframework.checker.nullness.compatqual.NullableType;
 /** Track selection related utility methods. */
 public final class TrackSelectionUtil {
  private TrackSelectionUtil() {}
+  /** Functional interface to create a single adaptive track selection. */
+  public interface AdaptiveTrackSelectionFactory {
+    /**
+     * Creates an adaptive track selection for the provided track selection definition.
+     *
+     * @param trackSelectionDefinition A {@link Definition} for the track selection.
+     * @return The created track selection.
+     */
+    TrackSelection createAdaptiveTrackSelection(Definition trackSelectionDefinition);
+  }
+  /**
+   * Creates track selections for an array of track selection definitions, with at most one
+   * multi-track adaptive selection.
+   *
+   * @param definitions The list of track selection {@link Definition definitions}. May include null
+   *     values.
+   * @param adaptiveTrackSelectionFactory A factory for the multi-track adaptive track selection.
+   * @return The array of created track selection. For null entries in {@code definitions} returns
+   *     null values.
+   */
+  public static @NullableType TrackSelection[] createTrackSelectionsForDefinitions(
+      @NullableType Definition[] definitions,
+      AdaptiveTrackSelectionFactory adaptiveTrackSelectionFactory) {
+    TrackSelection[] selections = new TrackSelection[definitions.length];
+    boolean createdAdaptiveTrackSelection = false;
+    for (int i = 0; i < definitions.length; i++) {
+      Definition definition = definitions[i];
+      if (definition == null) {
+        continue;
+      }
+      if (definition.tracks.length > 1 && !createdAdaptiveTrackSelection) {
+        createdAdaptiveTrackSelection = true;
+        selections[i] = adaptiveTrackSelectionFactory.createAdaptiveTrackSelection(definition);
+      } else {
+        selections[i] = new FixedTrackSelection(definition.group, definition.tracks[0]);
+      }
+    }
+    return selections;
+  }
  /**
   * Returns average bitrate for chunks in bits per second. Chunks are included in average until
   * {@code maxDurationMs} or the first unknown length chunk.

--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/DataSpec.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/DataSpec.java
@@ -108,10 +108,7 @@ public final class DataSpec {
   * {@link DataSpec} is not intended to be used in conjunction with a cache.
   */
  public final @Nullable String key;
-  /**
+  /** Request {@link Flags flags}. */
-   * Request flags. Currently {@link #FLAG_ALLOW_GZIP} and
-   * {@link #FLAG_ALLOW_CACHING_UNKNOWN_LENGTH} are the only supported flags.
-   */
  public final @Flags int flags;
  /**

--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/Cache.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/Cache.java
@@ -62,7 +62,7 @@ public interface Cache {
    void onSpanTouched(Cache cache, CacheSpan oldSpan, CacheSpan newSpan);
  }
  /**
   * Thrown when an error is encountered when writing data.
   */
@@ -82,7 +82,7 @@ public interface Cache {
   * Releases the cache. This method must be called when the cache is no longer required. The cache
   * must not be used after calling this method.
   */
-  void release() throws CacheException;
+  void release();
  /**
   * Registers a listener to listen for changes to a given key.
@@ -224,25 +224,6 @@ public interface Cache {
  long getCachedLength(String key, long position, long length);
  /**
-   * Sets the content length for the given key.
-   *
-   * @param key The cache key for the data.
-   * @param length The length of the data.
-   * @throws CacheException If an error is encountered.
-   */
-  void setContentLength(String key, long length) throws CacheException;
-  /**
-   * Returns the content length for the given key if one set, or {@link
-   * com.google.android.exoplayer2.C#LENGTH_UNSET} otherwise.
-   *
-   * @param key The cache key for the data.
-   * @return The content length for the given key if one set, or {@link
-   *     com.google.android.exoplayer2.C#LENGTH_UNSET} otherwise.
-   */
-  long getContentLength(String key);
-  /**
   * Applies {@code mutations} to the {@link ContentMetadata} for the given key. A new {@link
   * CachedContent} is added if there isn't one already with the given key.
   *

--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/CacheDataSource.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/CacheDataSource.java
@@ -42,10 +42,6 @@ import java.util.Map;
 * A {@link DataSource} that reads and writes a {@link Cache}. Requests are fulfilled from the cache
 * when possible. When data is not cached it is requested from an upstream {@link DataSource} and
 * written into the cache.
- *
- * <p>By default requests whose length can not be resolved are not cached. This is to prevent
- * caching of progressive live streams, which should usually not be cached. Caching of this kind of
- * requests can be enabled per request with {@link DataSpec#FLAG_ALLOW_CACHING_UNKNOWN_LENGTH}.
 */
 public final class CacheDataSource implements DataSource {
@@ -303,7 +299,7 @@ public final class CacheDataSource implements DataSource {
      if (dataSpec.length != C.LENGTH_UNSET || currentRequestIgnoresCache) {
        bytesRemaining = dataSpec.length;
      } else {
-        bytesRemaining = cache.getContentLength(key);
+        bytesRemaining = ContentMetadata.getContentLength(cache.getContentMetadata(key));
        if (bytesRemaining != C.LENGTH_UNSET) {
          bytesRemaining -= dataSpec.position;
          if (bytesRemaining <= 0) {
@@ -488,16 +484,12 @@ public final class CacheDataSource implements DataSource {
    ContentMetadataMutations mutations = new ContentMetadataMutations();
    if (currentDataSpecLengthUnset && resolvedLength != C.LENGTH_UNSET) {
      bytesRemaining = resolvedLength;
-      ContentMetadataInternal.setContentLength(mutations, readPosition + bytesRemaining);
+      ContentMetadataMutations.setContentLength(mutations, readPosition + bytesRemaining);
    }
    if (isReadingFromUpstream()) {
      actualUri = currentDataSource.getUri();
      boolean isRedirected = !uri.equals(actualUri);
-      if (isRedirected) {
+      ContentMetadataMutations.setRedirectedUri(mutations, isRedirected ? actualUri : null);
-        ContentMetadataInternal.setRedirectedUri(mutations, actualUri);
-      } else {
-        ContentMetadataInternal.removeRedirectedUri(mutations);
-      }
    }
    if (isWritingToCache()) {
      cache.applyContentMetadataMutations(key, mutations);
@@ -507,14 +499,15 @@ public final class CacheDataSource implements DataSource {
  private void setNoBytesRemainingAndMaybeStoreLength() throws IOException {
    bytesRemaining = 0;
    if (isWritingToCache()) {
-      cache.setContentLength(key, readPosition);
+      ContentMetadataMutations mutations = new ContentMetadataMutations();
+      ContentMetadataMutations.setContentLength(mutations, readPosition);
+      cache.applyContentMetadataMutations(key, mutations);
    }
  }
  private static Uri getRedirectedUriOrDefault(Cache cache, String key, Uri defaultUri) {
-    ContentMetadata contentMetadata = cache.getContentMetadata(key);
+    Uri redirectedUri = ContentMetadata.getRedirectedUri(cache.getContentMetadata(key));
-    Uri redirectedUri = ContentMetadataInternal.getRedirectedUri(contentMetadata);
+    return redirectedUri != null ? redirectedUri : defaultUri;
-    return redirectedUri == null ? defaultUri : redirectedUri;
  }
  private static boolean isCausedByPositionOutOfRange(IOException e) {

--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/CacheUtil.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/CacheUtil.java
@@ -84,7 +84,10 @@ public final class CacheUtil {
      CachingCounters counters) {
    String key = buildCacheKey(dataSpec, cacheKeyFactory);
    long start = dataSpec.absoluteStreamPosition;
-    long left = dataSpec.length != C.LENGTH_UNSET ? dataSpec.length : cache.getContentLength(key);
+    long left =
+        dataSpec.length != C.LENGTH_UNSET
+            ? dataSpec.length
+            : ContentMetadata.getContentLength(cache.getContentMetadata(key));
    counters.contentLength = left;
    counters.alreadyCachedBytes = 0;
    counters.newlyCachedBytes = 0;
@@ -188,7 +191,10 @@ public final class CacheUtil {
    String key = buildCacheKey(dataSpec, cacheKeyFactory);
    long start = dataSpec.absoluteStreamPosition;
-    long left = dataSpec.length != C.LENGTH_UNSET ? dataSpec.length : cache.getContentLength(key);
+    long left =
+        dataSpec.length != C.LENGTH_UNSET
+            ? dataSpec.length
+            : ContentMetadata.getContentLength(cache.getContentMetadata(key));
    while (left != 0) {
      throwExceptionIfInterruptedOrCancelled(isCanceled);
      long blockLength =

--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/CachedContent.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/CachedContent.java
@@ -55,7 +55,7 @@ import java.util.TreeSet;
    if (version < VERSION_METADATA_INTRODUCED) {
      long length = input.readLong();
      ContentMetadataMutations mutations = new ContentMetadataMutations();
-      ContentMetadataInternal.setContentLength(mutations, length);
+      ContentMetadataMutations.setContentLength(mutations, length);
      cachedContent.applyMetadataMutations(mutations);
    } else {
      cachedContent.metadata = DefaultContentMetadata.readFromStream(input);
@@ -216,7 +216,7 @@ import java.util.TreeSet;
    int result = id;
    result = 31 * result + key.hashCode();
    if (version < VERSION_METADATA_INTRODUCED) {
-      long length = ContentMetadataInternal.getContentLength(metadata);
+      long length = ContentMetadata.getContentLength(metadata);
      result = 31 * result + (int) (length ^ (length >>> 32));
    } else {
      result = 31 * result + metadata.hashCode();

--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/CachedContentIndex.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/CachedContentIndex.java
@@ -17,6 +17,7 @@ package com.google.android.exoplayer2.upstream.cache;
 import android.support.annotation.VisibleForTesting;
 import android.util.SparseArray;
+import android.util.SparseBooleanArray;
 import com.google.android.exoplayer2.upstream.cache.Cache.CacheException;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.AtomicFile;
@@ -42,6 +43,7 @@ import javax.crypto.CipherOutputStream;
 import javax.crypto.NoSuchPaddingException;
 import javax.crypto.spec.IvParameterSpec;
 import javax.crypto.spec.SecretKeySpec;
+import org.checkerframework.checker.nullness.compatqual.NullableType;
 /** Maintains the index of cached content. */
 /* package */ class CachedContentIndex {
@@ -53,7 +55,30 @@ import javax.crypto.spec.SecretKeySpec;
  private static final int FLAG_ENCRYPTED_INDEX = 1;
  private final HashMap<String, CachedContent> keyToContent;
-  private final SparseArray<String> idToKey;
+  /**
+   * Maps assigned ids to their corresponding keys. Also contains (id -> null) entries for ids that
+   * have been removed from the index since it was last stored. This prevents reuse of these ids,
+   * which is necessary to avoid clashes that could otherwise occur as a result of the sequence:
+   *
+   * <p>[1] (key1, id1) is removed from the in-memory index ... the index is not stored to disk ...
+   * [2] id1 is reused for a different key2 ... the index is not stored to disk ... [3] A file for
+   * key2 is partially written using a path corresponding to id1 ... the process is killed before
+   * the index is stored to disk ... [4] The index is read from disk, causing the partially written
+   * file to be incorrectly associated to key1
+   *
+   * <p>By avoiding id reuse in step [2], a new id2 will be used instead. Step [4] will then delete
+   * the partially written file because the index does not contain an entry for id2.
+   *
+   * <p>When the index is next stored (id -> null) entries are removed, making the ids eligible for
+   * reuse.
+   */
+  private final SparseArray<@NullableType String> idToKey;
+  /**
+   * Tracks ids for which (id -> null) entries are present in idToKey, so that they can be removed
+   * efficiently when the index is next stored.
+   */
+  private final SparseBooleanArray removedIds;
  private final AtomicFile atomicFile;
  private final Cipher cipher;
  private final SecretKeySpec secretKeySpec;
@@ -105,6 +130,7 @@ import javax.crypto.spec.SecretKeySpec;
    }
    keyToContent = new HashMap<>();
    idToKey = new SparseArray<>();
+    removedIds = new SparseBooleanArray();
    atomicFile = new AtomicFile(new File(cacheDir, FILE_NAME));
  }
@@ -125,6 +151,12 @@ import javax.crypto.spec.SecretKeySpec;
    }
    writeFile();
    changed = false;
+    // Make ids that were removed since the index was last stored eligible for re-use.
+    int removedIdCount = removedIds.size();
+    for (int i = 0; i < removedIdCount; i++) {
+      idToKey.remove(removedIds.keyAt(i));
+    }
+    removedIds.clear();
  }
  /**
@@ -169,8 +201,11 @@ import javax.crypto.spec.SecretKeySpec;
    CachedContent cachedContent = keyToContent.get(key);
    if (cachedContent != null && cachedContent.isEmpty() && !cachedContent.isLocked()) {
      keyToContent.remove(key);
-      idToKey.remove(cachedContent.id);
      changed = true;
+      // Keep an entry in idToKey to stop the id from being reused until the index is next stored.
+      idToKey.put(cachedContent.id, /* value= */ null);
+      // Track that the entry should be removed from idToKey when the index is next stored.
+      removedIds.put(cachedContent.id, /* value= */ true);
    }
  }

--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/ContentMetadata.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/ContentMetadata.java
@@ -15,44 +15,73 @@
 */
 package com.google.android.exoplayer2.upstream.cache;
+import android.net.Uri;
+import android.support.annotation.Nullable;
+import com.google.android.exoplayer2.C;
 /**
 * Interface for an immutable snapshot of keyed metadata.
- *
- * <p>Internal metadata names are prefixed with {@value #INTERNAL_METADATA_NAME_PREFIX}. Custom
- * metadata names should avoid this prefix to prevent clashes.
 */
 public interface ContentMetadata {
-  /** Prefix of internal metadata names. */
+  /**
-  String INTERNAL_METADATA_NAME_PREFIX = "exo_";
+   * Prefix for custom metadata keys. Applications can use keys starting with this prefix without
+   * any risk of their keys colliding with ones defined by the ExoPlayer library.
+   */
+  @SuppressWarnings("unused")
+  String KEY_CUSTOM_PREFIX = "custom_";
+  /** Key for redirected uri (type: String). */
+  String KEY_REDIRECTED_URI = "exo_redir";
+  /** Key for content length in bytes (type: long). */
+  String KEY_CONTENT_LENGTH = "exo_len";
  /**
   * Returns a metadata value.
   *
-   * @param name Name of the metadata to be returned.
+   * @param key Key of the metadata to be returned.
   * @param defaultValue Value to return if the metadata doesn't exist.
   * @return The metadata value.
   */
-  byte[] get(String name, byte[] defaultValue);
+  @Nullable
+  byte[] get(String key, @Nullable byte[] defaultValue);
  /**
   * Returns a metadata value.
   *
-   * @param name Name of the metadata to be returned.
+   * @param key Key of the metadata to be returned.
   * @param defaultValue Value to return if the metadata doesn't exist.
   * @return The metadata value.
   */
-  String get(String name, String defaultValue);
+  @Nullable
+  String get(String key, @Nullable String defaultValue);
  /**
   * Returns a metadata value.
   *
-   * @param name Name of the metadata to be returned.
+   * @param key Key of the metadata to be returned.
   * @param defaultValue Value to return if the metadata doesn't exist.
   * @return The metadata value.
   */
-  long get(String name, long defaultValue);
+  long get(String key, long defaultValue);
  /** Returns whether the metadata is available. */
-  boolean contains(String name);
+  boolean contains(String key);
+  /**
+   * Returns the value stored under {@link #KEY_CONTENT_LENGTH}, or {@link C#LENGTH_UNSET} if not
+   * set.
+   */
+  static long getContentLength(ContentMetadata contentMetadata) {
+    return contentMetadata.get(KEY_CONTENT_LENGTH, C.LENGTH_UNSET);
+  }
+  /**
+   * Returns the value stored under {@link #KEY_REDIRECTED_URI} as a {@link Uri}, or {code null} if
+   * not set.
+   */
+  @Nullable
+  static Uri getRedirectedUri(ContentMetadata contentMetadata) {
+    String redirectedUri = contentMetadata.get(KEY_REDIRECTED_URI, (String) null);
+    return redirectedUri == null ? null : Uri.parse(redirectedUri);
+  }
 }
--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/ContentMetadataInternal.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/ContentMetadataInternal.java
-/*
- * Copyright (C) 2018 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.google.android.exoplayer2.upstream.cache;
-import android.net.Uri;
-import android.support.annotation.Nullable;
-import com.google.android.exoplayer2.C;
-/** Helper classes to easily access and modify internal metadata values. */
-/* package */ final class ContentMetadataInternal {
-  private static final String PREFIX = ContentMetadata.INTERNAL_METADATA_NAME_PREFIX;
-  private static final String METADATA_NAME_REDIRECTED_URI = PREFIX + "redir";
-  private static final String METADATA_NAME_CONTENT_LENGTH = PREFIX + "len";
-  /** Returns the content length metadata, or {@link C#LENGTH_UNSET} if not set. */
-  public static long getContentLength(ContentMetadata contentMetadata) {
-    return contentMetadata.get(METADATA_NAME_CONTENT_LENGTH, C.LENGTH_UNSET);
-  }
-  /** Adds a mutation to set content length metadata value. */
-  public static void setContentLength(ContentMetadataMutations mutations, long length) {
-    mutations.set(METADATA_NAME_CONTENT_LENGTH, length);
-  }
-  /** Adds a mutation to remove content length metadata value. */
-  public static void removeContentLength(ContentMetadataMutations mutations) {
-    mutations.remove(METADATA_NAME_CONTENT_LENGTH);
-  }
-  /** Returns the redirected uri metadata, or {@code null} if not set. */
-  public @Nullable static Uri getRedirectedUri(ContentMetadata contentMetadata) {
-    String redirectedUri = contentMetadata.get(METADATA_NAME_REDIRECTED_URI, (String) null);
-    return redirectedUri == null ? null : Uri.parse(redirectedUri);
-  }
-  /**
-   * Adds a mutation to set redirected uri metadata value. Passing {@code null} as {@code uri} isn't
-   * allowed.
-   */
-  public static void setRedirectedUri(ContentMetadataMutations mutations, Uri uri) {
-    mutations.set(METADATA_NAME_REDIRECTED_URI, uri.toString());
-  }
-  /** Adds a mutation to remove redirected uri metadata value. */
-  public static void removeRedirectedUri(ContentMetadataMutations mutations) {
-    mutations.remove(METADATA_NAME_REDIRECTED_URI);
-  }
-  private ContentMetadataInternal() {
-    // Prevent instantiation.
-  }
-}
--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/ContentMetadataMutations.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/ContentMetadataMutations.java
@@ -15,6 +15,9 @@
 */
 package com.google.android.exoplayer2.upstream.cache;
+import android.net.Uri;
+import android.support.annotation.Nullable;
+import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.util.Assertions;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -30,6 +33,36 @@ import java.util.Map.Entry;
 */
 public class ContentMetadataMutations {
+  /**
+   * Adds a mutation to set the {@link ContentMetadata#KEY_CONTENT_LENGTH} value, or to remove any
+   * existing value if {@link C#LENGTH_UNSET} is passed.
+   *
+   * @param mutations The mutations to modify.
+   * @param length The length value, or {@link C#LENGTH_UNSET} to remove any existing entry.
+   * @return The mutations instance, for convenience.
+   */
+  public static ContentMetadataMutations setContentLength(
+      ContentMetadataMutations mutations, long length) {
+    return mutations.set(ContentMetadata.KEY_CONTENT_LENGTH, length);
+  }
+  /**
+   * Adds a mutation to set the {@link ContentMetadata#KEY_REDIRECTED_URI} value, or to remove any
+   * existing entry if {@code null} is passed.
+   *
+   * @param mutations The mutations to modify.
+   * @param uri The {@link Uri} value, or {@code null} to remove any existing entry.
+   * @return The mutations instance, for convenience.
+   */
+  public static ContentMetadataMutations setRedirectedUri(
+      ContentMetadataMutations mutations, @Nullable Uri uri) {
+    if (uri == null) {
+      return mutations.remove(ContentMetadata.KEY_REDIRECTED_URI);
+    } else {
+      return mutations.set(ContentMetadata.KEY_REDIRECTED_URI, uri.toString());
+    }
+  }
  private final Map<String, Object> editedValues;
  private final List<String> removedValues;
@@ -45,7 +78,7 @@ public class ContentMetadataMutations {
   *
   * @param name The name of the metadata value.
   * @param value The value to be set.
-   * @return This Editor instance, for convenience.
+   * @return This instance, for convenience.
   */
  public ContentMetadataMutations set(String name, String value) {
    return checkAndSet(name, value);
@@ -56,7 +89,7 @@ public class ContentMetadataMutations {
   *
   * @param name The name of the metadata value.
   * @param value The value to be set.
-   * @return This Editor instance, for convenience.
+   * @return This instance, for convenience.
   */
  public ContentMetadataMutations set(String name, long value) {
    return checkAndSet(name, value);
@@ -68,7 +101,7 @@ public class ContentMetadataMutations {
   *
   * @param name The name of the metadata value.
   * @param value The value to be set.
-   * @return This Editor instance, for convenience.
+   * @return This instance, for convenience.
   */
  public ContentMetadataMutations set(String name, byte[] value) {
    return checkAndSet(name, Arrays.copyOf(value, value.length));
@@ -78,7 +111,7 @@ public class ContentMetadataMutations {
   * Adds a mutation to remove a metadata value.
   *
   * @param name The name of the metadata value.
-   * @return This Editor instance, for convenience.
+   * @return This instance, for convenience.
   */
  public ContentMetadataMutations remove(String name) {
    removedValues.add(name);

--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/DefaultContentMetadata.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/DefaultContentMetadata.java
@@ -64,6 +64,10 @@ public final class DefaultContentMetadata implements ContentMetadata {
  private final Map<String, byte[]> metadata;
+  public DefaultContentMetadata() {
+    this(Collections.emptyMap());
+  }
  private DefaultContentMetadata(Map<String, byte[]> metadata) {
    this.metadata = Collections.unmodifiableMap(metadata);
  }
@@ -74,7 +78,7 @@ public final class DefaultContentMetadata implements ContentMetadata {
   */
  public DefaultContentMetadata copyWithMutationsApplied(ContentMetadataMutations mutations) {
    Map<String, byte[]> mutatedMetadata = applyMutations(metadata, mutations);
-    if (isMetadataEqual(mutatedMetadata)) {
+    if (isMetadataEqual(metadata, mutatedMetadata)) {
      return this;
    }
    return new DefaultContentMetadata(mutatedMetadata);
@@ -97,7 +101,8 @@ public final class DefaultContentMetadata implements ContentMetadata {
  }
  @Override
-  public final byte[] get(String name, byte[] defaultValue) {
+  @Nullable
+  public final byte[] get(String name, @Nullable byte[] defaultValue) {
    if (metadata.containsKey(name)) {
      byte[] bytes = metadata.get(name);
      return Arrays.copyOf(bytes, bytes.length);
@@ -107,7 +112,8 @@ public final class DefaultContentMetadata implements ContentMetadata {
  }
  @Override
-  public final String get(String name, String defaultValue) {
+  @Nullable
+  public final String get(String name, @Nullable String defaultValue) {
    if (metadata.containsKey(name)) {
      byte[] bytes = metadata.get(name);
      return new String(bytes, Charset.forName(C.UTF8_NAME));
@@ -139,21 +145,7 @@ public final class DefaultContentMetadata implements ContentMetadata {
    if (o == null || getClass() != o.getClass()) {
      return false;
    }
-    return isMetadataEqual(((DefaultContentMetadata) o).metadata);
+    return isMetadataEqual(metadata, ((DefaultContentMetadata) o).metadata);
-  }
-  private boolean isMetadataEqual(Map<String, byte[]> otherMetadata) {
-    if (metadata.size() != otherMetadata.size()) {
-      return false;
-    }
-    for (Entry<String, byte[]> entry : metadata.entrySet()) {
-      byte[] value = entry.getValue();
-      byte[] otherValue = otherMetadata.get(entry.getKey());
-      if (!Arrays.equals(value, otherValue)) {
-        return false;
-      }
-    }
-    return true;
  }
  @Override
@@ -168,6 +160,20 @@ public final class DefaultContentMetadata implements ContentMetadata {
    return hashCode;
  }
+  private static boolean isMetadataEqual(Map<String, byte[]> first, Map<String, byte[]> second) {
+    if (first.size() != second.size()) {
+      return false;
+    }
+    for (Entry<String, byte[]> entry : first.entrySet()) {
+      byte[] value = entry.getValue();
+      byte[] otherValue = second.get(entry.getKey());
+      if (!Arrays.equals(value, otherValue)) {
+        return false;
+      }
+    }
+    return true;
+  }
  private static Map<String, byte[]> applyMutations(
      Map<String, byte[]> otherMetadata, ContentMetadataMutations mutations) {
    HashMap<String, byte[]> metadata = new HashMap<>(otherMetadata);

--- a/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/SimpleCache.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/SimpleCache.java
@@ -146,13 +146,16 @@ public final class SimpleCache implements Cache {
  }
  @Override
-  public synchronized void release() throws CacheException {
+  public synchronized void release() {
    if (released) {
      return;
    }
    listeners.clear();
+    removeStaleSpans();
    try {
-      removeStaleSpansAndCachedContents();
+      index.store();
+    } catch (CacheException e) {
+      Log.e(TAG, "Storing index file failed", e);
    } finally {
      unlockFolder(cacheDir);
      released = true;
@@ -265,7 +268,7 @@ public final class SimpleCache implements Cache {
    if (!cacheDir.exists()) {
      // For some reason the cache directory doesn't exist. Make a best effort to create it.
      cacheDir.mkdirs();
-      removeStaleSpansAndCachedContents();
+      removeStaleSpans();
    }
    evictor.onStartFile(this, key, position, maxLength);
    return SimpleCacheSpan.getCacheFile(
@@ -290,7 +293,7 @@ public final class SimpleCache implements Cache {
      return;
    }
    // Check if the span conflicts with the set content length
-    long length = ContentMetadataInternal.getContentLength(cachedContent.getMetadata());
+    long length = ContentMetadata.getContentLength(cachedContent.getMetadata());
    if (length != C.LENGTH_UNSET) {
      Assertions.checkState((span.position + span.length) <= length);
    }
@@ -311,9 +314,9 @@ public final class SimpleCache implements Cache {
  }
  @Override
-  public synchronized void removeSpan(CacheSpan span) throws CacheException {
+  public synchronized void removeSpan(CacheSpan span) {
    Assertions.checkState(!released);
-    removeSpan(span, true);
+    removeSpanInternal(span);
  }
  @Override
@@ -331,18 +334,6 @@ public final class SimpleCache implements Cache {
  }
  @Override
-  public synchronized void setContentLength(String key, long length) throws CacheException {
-    ContentMetadataMutations mutations = new ContentMetadataMutations();
-    ContentMetadataInternal.setContentLength(mutations, length);
-    applyContentMetadataMutations(key, mutations);
-  }
-  @Override
-  public synchronized long getContentLength(String key) {
-    return ContentMetadataInternal.getContentLength(getContentMetadata(key));
-  }
-  @Override
  public synchronized void applyContentMetadataMutations(
      String key, ContentMetadataMutations mutations) throws CacheException {
    Assertions.checkState(!released);
@@ -379,7 +370,7 @@ public final class SimpleCache implements Cache {
      if (span.isCached && !span.file.exists()) {
        // The file has been deleted from under us. It's likely that other files will have been
        // deleted too, so scan the whole in-memory representation.
-        removeStaleSpansAndCachedContents();
+        removeStaleSpans();
        continue;
      }
      return span;
@@ -431,27 +422,21 @@ public final class SimpleCache implements Cache {
    notifySpanAdded(span);
  }
-  private void removeSpan(CacheSpan span, boolean removeEmptyCachedContent) throws CacheException {
+  private void removeSpanInternal(CacheSpan span) {
    CachedContent cachedContent = index.get(span.key);
    if (cachedContent == null || !cachedContent.removeSpan(span)) {
      return;
    }
    totalSpace -= span.length;
-    try {
+    index.maybeRemove(cachedContent.key);
-      if (removeEmptyCachedContent) {
+    notifySpanRemoved(span);
-        index.maybeRemove(cachedContent.key);
-        index.store();
-      }
-    } finally {
-      notifySpanRemoved(span);
-    }
  }
  /**
   * Scans all of the cached spans in the in-memory representation, removing any for which files no
   * longer exist.
   */
-  private void removeStaleSpansAndCachedContents() throws CacheException {
+  private void removeStaleSpans() {
    ArrayList<CacheSpan> spansToBeRemoved = new ArrayList<>();
    for (CachedContent cachedContent : index.getAll()) {
      for (CacheSpan span : cachedContent.getSpans()) {
@@ -461,11 +446,8 @@ public final class SimpleCache implements Cache {
      }
    }
    for (int i = 0; i < spansToBeRemoved.size(); i++) {
-      // Remove span but not CachedContent to prevent multiple index.store() calls.
+      removeSpanInternal(spansToBeRemoved.get(i));
-      removeSpan(spansToBeRemoved.get(i), false);
    }
-    index.removeEmpty();
-    index.store();
  }
  private void notifySpanRemoved(CacheSpan span) {

--- a/library/core/src/main/java/com/google/android/exoplayer2/video/MediaCodecVideoRenderer.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/video/MediaCodecVideoRenderer.java
--- a/library/core/src/test/assets/ttml/bitmap_percentage_region.xml
+++ b/library/core/src/test/assets/ttml/bitmap_percentage_region.xml
+<tt xmlns="http://www.w3.org/ns/ttml" xmlns:ttm="http://www.w3.org/ns/ttml#metadata" xmlns:tts="http://www.w3.org/ns/ttml#styling" xmlns:smpte="http://www.smpte-ra.org/schemas/2052-1/2010/smpte-tt" xml:lang="eng">
+    <head>
+        <metadata>
+            <smpte:image imagetype="PNG" encoding="Base64" xml:id="img_0">
+                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
+            </smpte:image>
+            <smpte:image imagetype="PNG" encoding="Base64" xml:id="img_1">
+                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
+            </smpte:image>
+        </metadata>
+        <styling>
+            <style/>
+        </styling>
+        <layout>
+            <region xml:id="region_0" tts:extent="51% 12%" tts:origin="24% 78%"/>
+            <region xml:id="region_1" tts:extent="57% 6%" tts:origin="21% 85%"/>
+            <region xml:id="region_2" tts:extent="51% 12%" tts:origin="24% 28%"/>
+            <region xml:id="region_3" tts:extent="57% 6%" tts:origin="21% 35%"/>
+        </layout>
+    </head>
+    <body>
+        <div begin="00:00:00.200" end="00:00:03.000" region="region_2" smpte:backgroundImage="#img_0"/>
+        <div begin="00:00:03.200" end="00:00:06.937" region="region_3" smpte:backgroundImage="#img_1"/>
+        <div begin="00:00:07.200" end="00:59:03.000" region="region_2" smpte:backgroundImage="#img_0"/>
+    </body>
+</tt>
--- a/library/core/src/test/assets/ttml/bitmap_pixel_region.xml
+++ b/library/core/src/test/assets/ttml/bitmap_pixel_region.xml
+<tt xmlns="http://www.w3.org/ns/ttml" xmlns:ttm="http://www.w3.org/ns/ttml#metadata" xmlns:tts="http://www.w3.org/ns/ttml#styling" xmlns:smpte="http://www.smpte-ra.org/schemas/2052-1/2010/smpte-tt" xml:lang="eng" tts:extent="1280px 720px">
+    <head>
+        <metadata>
+            <smpte:image imagetype="PNG" encoding="Base64" xml:id="img_0">
+                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
+            </smpte:image>
+            <smpte:image imagetype="PNG" encoding="Base64" xml:id="img_1">
+                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
+            </smpte:image>
+        </metadata>
+        <styling>
+            <style/>
+        </styling>
+        <layout>
+            <region xml:id="region_0" tts:extent="653px 86px" tts:origin="307px 562px"/>
+            <region xml:id="region_1" tts:extent="730px 43px" tts:origin="269px 612px"/>
+        </layout>
+    </head>
+    <body>
+        <div begin="00:00:00.200" end="00:00:03.000" region="region_0" smpte:backgroundImage="#img_0"/>
+        <div begin="00:00:03.200" end="00:00:06.937" region="region_1" smpte:backgroundImage="#img_1"/>
+    </body>
+</tt>
--- a/library/core/src/test/assets/ttml/bitmap_unsupported_region.xml
+++ b/library/core/src/test/assets/ttml/bitmap_unsupported_region.xml
+<tt xmlns="http://www.w3.org/ns/ttml" xmlns:ttm="http://www.w3.org/ns/ttml#metadata" xmlns:tts="http://www.w3.org/ns/ttml#styling" xmlns:smpte="http://www.smpte-ra.org/schemas/2052-1/2010/smpte-tt" xml:lang="eng">
+    <head>
+        <metadata>
+            <smpte:image imagetype="PNG" encoding="Base64" xml:id="img_0">
+                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
+            </smpte:image>
+            <smpte:image imagetype="PNG" encoding="Base64" xml:id="img_1">
+                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
+            </smpte:image>
+        </metadata>
+        <styling>
+            <style/>
+        </styling>
+        <layout>
+            <region xml:id="region_0" tts:extent="653px 86px" tts:origin="307px 562px"/>
+            <region xml:id="region_1" tts:extent="730px 43px" tts:origin="269px 612px"/>
+        </layout>
+    </head>
+    <body>
+        <div begin="00:00:00.200" end="00:00:03.000" region="region_0" smpte:backgroundImage="#img_0"/>
+        <div begin="00:00:03.200" end="00:00:06.937" region="region_1" smpte:backgroundImage="#img_1"/>
+    </body>
+</tt>
--- a/library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadActionUtilTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadActionUtilTest.java
--- a/library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadHelperTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadHelperTest.java
--- a/library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadManagerTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/offline/DownloadManagerTest.java
--- a/library/core/src/test/java/com/google/android/exoplayer2/text/ttml/TtmlDecoderTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/text/ttml/TtmlDecoderTest.java
@@ -63,6 +63,9 @@ public final class TtmlDecoderTest {
  private static final String FONT_SIZE_INVALID_TTML_FILE = "ttml/font_size_invalid.xml";
  private static final String FONT_SIZE_EMPTY_TTML_FILE = "ttml/font_size_empty.xml";
  private static final String FRAME_RATE_TTML_FILE = "ttml/frame_rate.xml";
+  private static final String BITMAP_REGION_FILE = "ttml/bitmap_percentage_region.xml";
+  private static final String BITMAP_PIXEL_REGION_FILE = "ttml/bitmap_pixel_region.xml";
+  private static final String BITMAP_UNSUPPORTED_REGION_FILE = "ttml/bitmap_unsupported_region.xml";
  @Test
  public void testInlineAttributes() throws IOException, SubtitleDecoderException {
@@ -259,56 +262,56 @@ public final class TtmlDecoderTest {
  @Test
  public void testMultipleRegions() throws IOException, SubtitleDecoderException {
    TtmlSubtitle subtitle = getSubtitle(MULTIPLE_REGIONS_TTML_FILE);
-    List<Cue> output = subtitle.getCues(1000000);
+    List<Cue> cues = subtitle.getCues(1000000);
-    assertThat(output).hasSize(2);
+    assertThat(cues).hasSize(2);
-    Cue ttmlCue = output.get(0);
+    Cue cue = cues.get(0);
-    assertThat(ttmlCue.text.toString()).isEqualTo("lorem");
+    assertThat(cue.text.toString()).isEqualTo("lorem");
-    assertThat(ttmlCue.position).isEqualTo(10f / 100f);
+    assertThat(cue.position).isEqualTo(10f / 100f);
-    assertThat(ttmlCue.line).isEqualTo(10f / 100f);
+    assertThat(cue.line).isEqualTo(10f / 100f);
-    assertThat(ttmlCue.size).isEqualTo(20f / 100f);
+    assertThat(cue.size).isEqualTo(20f / 100f);
-    ttmlCue = output.get(1);
+    cue = cues.get(1);
-    assertThat(ttmlCue.text.toString()).isEqualTo("amet");
+    assertThat(cue.text.toString()).isEqualTo("amet");
-    assertThat(ttmlCue.position).isEqualTo(60f / 100f);
+    assertThat(cue.position).isEqualTo(60f / 100f);
-    assertThat(ttmlCue.line).isEqualTo(10f / 100f);
+    assertThat(cue.line).isEqualTo(10f / 100f);
-    assertThat(ttmlCue.size).isEqualTo(20f / 100f);
+    assertThat(cue.size).isEqualTo(20f / 100f);
-    output = subtitle.getCues(5000000);
+    cues = subtitle.getCues(5000000);
-    assertThat(output).hasSize(1);
+    assertThat(cues).hasSize(1);
-    ttmlCue = output.get(0);
+    cue = cues.get(0);
-    assertThat(ttmlCue.text.toString()).isEqualTo("ipsum");
+    assertThat(cue.text.toString()).isEqualTo("ipsum");
-    assertThat(ttmlCue.position).isEqualTo(40f / 100f);
+    assertThat(cue.position).isEqualTo(40f / 100f);
-    assertThat(ttmlCue.line).isEqualTo(40f / 100f);
+    assertThat(cue.line).isEqualTo(40f / 100f);
-    assertThat(ttmlCue.size).isEqualTo(20f / 100f);
+    assertThat(cue.size).isEqualTo(20f / 100f);
-    output = subtitle.getCues(9000000);
+    cues = subtitle.getCues(9000000);
-    assertThat(output).hasSize(1);
+    assertThat(cues).hasSize(1);
-    ttmlCue = output.get(0);
+    cue = cues.get(0);
-    assertThat(ttmlCue.text.toString()).isEqualTo("dolor");
+    assertThat(cue.text.toString()).isEqualTo("dolor");
-    assertThat(ttmlCue.position).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.position).isEqualTo(Cue.DIMEN_UNSET);
-    assertThat(ttmlCue.line).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.line).isEqualTo(Cue.DIMEN_UNSET);
-    assertThat(ttmlCue.size).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.size).isEqualTo(Cue.DIMEN_UNSET);
    // TODO: Should be as below, once https://github.com/google/ExoPlayer/issues/2953 is fixed.
-    // assertEquals(10f / 100f, ttmlCue.position);
+    // assertEquals(10f / 100f, cue.position);
-    // assertEquals(80f / 100f, ttmlCue.line);
+    // assertEquals(80f / 100f, cue.line);
-    // assertEquals(1f, ttmlCue.size);
+    // assertEquals(1f, cue.size);
-    output = subtitle.getCues(21000000);
+    cues = subtitle.getCues(21000000);
-    assertThat(output).hasSize(1);
+    assertThat(cues).hasSize(1);
-    ttmlCue = output.get(0);
+    cue = cues.get(0);
-    assertThat(ttmlCue.text.toString()).isEqualTo("She first said this");
+    assertThat(cue.text.toString()).isEqualTo("She first said this");
-    assertThat(ttmlCue.position).isEqualTo(45f / 100f);
+    assertThat(cue.position).isEqualTo(45f / 100f);
-    assertThat(ttmlCue.line).isEqualTo(45f / 100f);
+    assertThat(cue.line).isEqualTo(45f / 100f);
-    assertThat(ttmlCue.size).isEqualTo(35f / 100f);
+    assertThat(cue.size).isEqualTo(35f / 100f);
-    output = subtitle.getCues(25000000);
+    cues = subtitle.getCues(25000000);
-    ttmlCue = output.get(0);
+    cue = cues.get(0);
-    assertThat(ttmlCue.text.toString()).isEqualTo("She first said this\nThen this");
+    assertThat(cue.text.toString()).isEqualTo("She first said this\nThen this");
-    output = subtitle.getCues(29000000);
+    cues = subtitle.getCues(29000000);
-    assertThat(output).hasSize(1);
+    assertThat(cues).hasSize(1);
-    ttmlCue = output.get(0);
+    cue = cues.get(0);
-    assertThat(ttmlCue.text.toString()).isEqualTo("She first said this\nThen this\nFinally this");
+    assertThat(cue.text.toString()).isEqualTo("She first said this\nThen this\nFinally this");
-    assertThat(ttmlCue.position).isEqualTo(45f / 100f);
+    assertThat(cue.position).isEqualTo(45f / 100f);
-    assertThat(ttmlCue.line).isEqualTo(45f / 100f);
+    assertThat(cue.line).isEqualTo(45f / 100f);
  }
  @Test
@@ -499,6 +502,91 @@ public final class TtmlDecoderTest {
    assertThat((double) subtitle.getEventTime(3)).isWithin(2000).of(2_002_000_000);
  }
+  @Test
+  public void testBitmapPercentageRegion() throws IOException, SubtitleDecoderException {
+    TtmlSubtitle subtitle = getSubtitle(BITMAP_REGION_FILE);
+    List<Cue> cues = subtitle.getCues(1000000);
+    assertThat(cues).hasSize(1);
+    Cue cue = cues.get(0);
+    assertThat(cue.text).isNull();
+    assertThat(cue.bitmap).isNotNull();
+    assertThat(cue.position).isEqualTo(24f / 100f);
+    assertThat(cue.line).isEqualTo(28f / 100f);
+    assertThat(cue.size).isEqualTo(51f / 100f);
+    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+    cues = subtitle.getCues(4000000);
+    assertThat(cues).hasSize(1);
+    cue = cues.get(0);
+    assertThat(cue.text).isNull();
+    assertThat(cue.bitmap).isNotNull();
+    assertThat(cue.position).isEqualTo(21f / 100f);
+    assertThat(cue.line).isEqualTo(35f / 100f);
+    assertThat(cue.size).isEqualTo(57f / 100f);
+    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+    cues = subtitle.getCues(7500000);
+    assertThat(cues).hasSize(1);
+    cue = cues.get(0);
+    assertThat(cue.text).isNull();
+    assertThat(cue.bitmap).isNotNull();
+    assertThat(cue.position).isEqualTo(24f / 100f);
+    assertThat(cue.line).isEqualTo(28f / 100f);
+    assertThat(cue.size).isEqualTo(51f / 100f);
+    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+  }
+  @Test
+  public void testBitmapPixelRegion() throws IOException, SubtitleDecoderException {
+    TtmlSubtitle subtitle = getSubtitle(BITMAP_PIXEL_REGION_FILE);
+    List<Cue> cues = subtitle.getCues(1000000);
+    assertThat(cues).hasSize(1);
+    Cue cue = cues.get(0);
+    assertThat(cue.text).isNull();
+    assertThat(cue.bitmap).isNotNull();
+    assertThat(cue.position).isEqualTo(307f / 1280f);
+    assertThat(cue.line).isEqualTo(562f / 720f);
+    assertThat(cue.size).isEqualTo(653f / 1280f);
+    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+    cues = subtitle.getCues(4000000);
+    assertThat(cues).hasSize(1);
+    cue = cues.get(0);
+    assertThat(cue.text).isNull();
+    assertThat(cue.bitmap).isNotNull();
+    assertThat(cue.position).isEqualTo(269f / 1280f);
+    assertThat(cue.line).isEqualTo(612f / 720f);
+    assertThat(cue.size).isEqualTo(730f / 1280f);
+    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+  }
+  @Test
+  public void testBitmapUnsupportedRegion() throws IOException, SubtitleDecoderException {
+    TtmlSubtitle subtitle = getSubtitle(BITMAP_UNSUPPORTED_REGION_FILE);
+    List<Cue> cues = subtitle.getCues(1000000);
+    assertThat(cues).hasSize(1);
+    Cue cue = cues.get(0);
+    assertThat(cue.text).isNull();
+    assertThat(cue.bitmap).isNotNull();
+    assertThat(cue.position).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.line).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.size).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+    cues = subtitle.getCues(4000000);
+    assertThat(cues).hasSize(1);
+    cue = cues.get(0);
+    assertThat(cue.text).isNull();
+    assertThat(cue.bitmap).isNotNull();
+    assertThat(cue.position).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.line).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.size).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+  }
  private void assertSpans(
      TtmlSubtitle subtitle,
      int second,

--- a/library/core/src/test/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelectionTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/trackselection/AdaptiveTrackSelectionTest.java
@@ -32,6 +32,7 @@ import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.chunk.MediaChunkIterator;
 import com.google.android.exoplayer2.testutil.FakeClock;
 import com.google.android.exoplayer2.testutil.FakeMediaChunk;
+import com.google.android.exoplayer2.trackselection.TrackSelection.Definition;
 import com.google.android.exoplayer2.upstream.BandwidthMeter;
 import com.google.android.exoplayer2.util.MimeTypes;
 import java.util.ArrayList;
@@ -66,15 +67,20 @@ public final class AdaptiveTrackSelectionTest {
  }
  @Test
+  @SuppressWarnings("deprecation")
  public void testFactoryUsesInitiallyProvidedBandwidthMeter() {
    BandwidthMeter initialBandwidthMeter = mock(BandwidthMeter.class);
    BandwidthMeter injectedBandwidthMeter = mock(BandwidthMeter.class);
-    Format format = videoFormat(/* bitrate= */ 500, /* width= */ 320, /* height= */ 240);
+    Format format1 = videoFormat(/* bitrate= */ 500, /* width= */ 320, /* height= */ 240);
-    @SuppressWarnings("deprecation")
+    Format format2 = videoFormat(/* bitrate= */ 1000, /* width= */ 640, /* height= */ 480);
-    AdaptiveTrackSelection adaptiveTrackSelection =
+    TrackSelection[] trackSelections =
        new AdaptiveTrackSelection.Factory(initialBandwidthMeter)
-            .createTrackSelection(new TrackGroup(format), injectedBandwidthMeter, /* tracks= */ 0);
+            .createTrackSelections(
-    adaptiveTrackSelection.updateSelectedTrack(
+                new Definition[] {
+                  new Definition(new TrackGroup(format1, format2), /* tracks= */ 0, 1)
+                },
+                injectedBandwidthMeter);
+    trackSelections[0].updateSelectedTrack(
        /* playbackPositionUs= */ 0,
        /* bufferedDurationUs= */ 0,
        /* availableDurationUs= */ C.TIME_UNSET,

--- a/library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/CacheDataSourceTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/CacheDataSourceTest.java
@@ -247,7 +247,8 @@ public final class CacheDataSourceTest {
    // Read partial at EOS but don't cross it so length is unknown.
    CacheDataSource cacheDataSource = createCacheDataSource(false, true);
    assertReadData(cacheDataSource, dataSpec, true);
-    assertThat(cache.getContentLength(defaultCacheKey)).isEqualTo(C.LENGTH_UNSET);
+    assertThat(ContentMetadata.getContentLength(cache.getContentMetadata(defaultCacheKey)))
+        .isEqualTo(C.LENGTH_UNSET);
    // Now do an unbounded request for whole data. This will cause a bounded request from upstream.
    // End of data from upstream shouldn't be mixed up with EOS and cause length set wrong.
@@ -285,7 +286,8 @@ public final class CacheDataSourceTest {
    cacheDataSource.close();
    assertThat(upstream.getAndClearOpenedDataSpecs()).hasLength(1);
-    assertThat(cache.getContentLength(defaultCacheKey)).isEqualTo(TEST_DATA.length);
+    assertThat(ContentMetadata.getContentLength(cache.getContentMetadata(defaultCacheKey)))
+        .isEqualTo(TEST_DATA.length);
  }
  @Test
@@ -467,11 +469,7 @@ public final class CacheDataSourceTest {
    NavigableSet<CacheSpan> cachedSpans = cache.getCachedSpans(defaultCacheKey);
    for (CacheSpan cachedSpan : cachedSpans) {
      if (cachedSpan.position >= halfDataLength) {
-        try {
+        cache.removeSpan(cachedSpan);
-          cache.removeSpan(cachedSpan);
-        } catch (Cache.CacheException e) {
-          // do nothing
-        }
      }
    }
@@ -516,7 +514,9 @@ public final class CacheDataSourceTest {
    // If the request was unbounded then the content length should be cached, either because the
    // content length was known or because EOS was read. If the request was bounded then the content
    // length will not have been determined.
-    assertThat(cache.getContentLength(customCacheKey ? this.customCacheKey : defaultCacheKey))
+    ContentMetadata metadata =
+        cache.getContentMetadata(customCacheKey ? this.customCacheKey : defaultCacheKey);
+    assertThat(ContentMetadata.getContentLength(metadata))
        .isEqualTo(dataSpec.length == C.LENGTH_UNSET ? TEST_DATA.length : C.LENGTH_UNSET);
  }

--- a/library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/CacheUtilTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/CacheUtilTest.java
@@ -79,8 +79,11 @@ public final class CacheUtilTest {
    }
    @Override
-    public long getContentLength(String key) {
+    public ContentMetadata getContentMetadata(String key) {
-      return contentLength;
+      DefaultContentMetadata metadata = new DefaultContentMetadata();
+      ContentMetadataMutations mutations = new ContentMetadataMutations();
+      ContentMetadataMutations.setContentLength(mutations, contentLength);
+      return metadata.copyWithMutationsApplied(mutations);
    }
  }

--- a/library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/CachedContentIndexTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/CachedContentIndexTest.java
@@ -154,11 +154,11 @@ public class CachedContentIndexTest {
    assertThat(index.assignIdForKey("ABCDE")).isEqualTo(5);
    ContentMetadata metadata = index.get("ABCDE").getMetadata();
-    assertThat(ContentMetadataInternal.getContentLength(metadata)).isEqualTo(10);
+    assertThat(ContentMetadata.getContentLength(metadata)).isEqualTo(10);
    assertThat(index.assignIdForKey("KLMNO")).isEqualTo(2);
    ContentMetadata metadata2 = index.get("KLMNO").getMetadata();
-    assertThat(ContentMetadataInternal.getContentLength(metadata2)).isEqualTo(2560);
+    assertThat(ContentMetadata.getContentLength(metadata2)).isEqualTo(2560);
  }
  @Test
@@ -172,12 +172,12 @@ public class CachedContentIndexTest {
    assertThat(index.assignIdForKey("ABCDE")).isEqualTo(5);
    ContentMetadata metadata = index.get("ABCDE").getMetadata();
-    assertThat(ContentMetadataInternal.getContentLength(metadata)).isEqualTo(10);
+    assertThat(ContentMetadata.getContentLength(metadata)).isEqualTo(10);
-    assertThat(ContentMetadataInternal.getRedirectedUri(metadata)).isEqualTo(Uri.parse("abcde"));
+    assertThat(ContentMetadata.getRedirectedUri(metadata)).isEqualTo(Uri.parse("abcde"));
    assertThat(index.assignIdForKey("KLMNO")).isEqualTo(2);
    ContentMetadata metadata2 = index.get("KLMNO").getMetadata();
-    assertThat(ContentMetadataInternal.getContentLength(metadata2)).isEqualTo(2560);
+    assertThat(ContentMetadata.getContentLength(metadata2)).isEqualTo(2560);
  }
  @Test
@@ -297,11 +297,11 @@ public class CachedContentIndexTest {
  private void assertStoredAndLoadedEqual(CachedContentIndex index, CachedContentIndex index2)
      throws IOException {
    ContentMetadataMutations mutations1 = new ContentMetadataMutations();
-    ContentMetadataInternal.setContentLength(mutations1, 2560);
+    ContentMetadataMutations.setContentLength(mutations1, 2560);
    index.getOrAdd("KLMNO").applyMetadataMutations(mutations1);
    ContentMetadataMutations mutations2 = new ContentMetadataMutations();
-    ContentMetadataInternal.setContentLength(mutations2, 10);
+    ContentMetadataMutations.setContentLength(mutations2, 10);
-    ContentMetadataInternal.setRedirectedUri(mutations2, Uri.parse("abcde"));
+    ContentMetadataMutations.setRedirectedUri(mutations2, Uri.parse("abcde"));
    index.getOrAdd("ABCDE").applyMetadataMutations(mutations2);
    index.store();

--- a/library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/SimpleCacheTest.java
+++ b/library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/SimpleCacheTest.java
@@ -47,6 +47,7 @@ import org.robolectric.RuntimeEnvironment;
 public class SimpleCacheTest {
  private static final String KEY_1 = "key1";
+  private static final String KEY_2 = "key2";
  private File cacheDir;
@@ -105,18 +106,26 @@ public class SimpleCacheTest {
  }
  @Test
-  public void testSetGetLength() throws Exception {
+  public void testSetGetContentMetadata() throws Exception {
    SimpleCache simpleCache = getSimpleCache();
-    assertThat(simpleCache.getContentLength(KEY_1)).isEqualTo(LENGTH_UNSET);
+    assertThat(ContentMetadata.getContentLength(simpleCache.getContentMetadata(KEY_1)))
+        .isEqualTo(LENGTH_UNSET);
-    simpleCache.setContentLength(KEY_1, 15);
+    ContentMetadataMutations mutations = new ContentMetadataMutations();
-    assertThat(simpleCache.getContentLength(KEY_1)).isEqualTo(15);
+    ContentMetadataMutations.setContentLength(mutations, 15);
+    simpleCache.applyContentMetadataMutations(KEY_1, mutations);
+    assertThat(ContentMetadata.getContentLength(simpleCache.getContentMetadata(KEY_1)))
+        .isEqualTo(15);
    simpleCache.startReadWrite(KEY_1, 0);
    addCache(simpleCache, KEY_1, 0, 15);
-    simpleCache.setContentLength(KEY_1, 150);
-    assertThat(simpleCache.getContentLength(KEY_1)).isEqualTo(150);
+    mutations = new ContentMetadataMutations();
+    ContentMetadataMutations.setContentLength(mutations, 150);
+    simpleCache.applyContentMetadataMutations(KEY_1, mutations);
+    assertThat(ContentMetadata.getContentLength(simpleCache.getContentMetadata(KEY_1)))
+        .isEqualTo(150);
    addCache(simpleCache, KEY_1, 140, 10);
@@ -124,14 +133,16 @@ public class SimpleCacheTest {
    // Check if values are kept after cache is reloaded.
    SimpleCache simpleCache2 = getSimpleCache();
-    assertThat(simpleCache2.getContentLength(KEY_1)).isEqualTo(150);
+    assertThat(ContentMetadata.getContentLength(simpleCache2.getContentMetadata(KEY_1)))
+        .isEqualTo(150);
    // Removing the last span shouldn't cause the length be change next time cache loaded
    SimpleCacheSpan lastSpan = simpleCache2.startReadWrite(KEY_1, 145);
    simpleCache2.removeSpan(lastSpan);
    simpleCache2.release();
    simpleCache2 = getSimpleCache();
-    assertThat(simpleCache2.getContentLength(KEY_1)).isEqualTo(150);
+    assertThat(ContentMetadata.getContentLength(simpleCache2.getContentMetadata(KEY_1)))
+        .isEqualTo(150);
  }
  @Test
@@ -153,6 +164,40 @@ public class SimpleCacheTest {
  }
  @Test
+  public void testReloadCacheWithoutRelease() throws Exception {
+    SimpleCache simpleCache = getSimpleCache();
+    // Write data for KEY_1.
+    CacheSpan cacheSpan1 = simpleCache.startReadWrite(KEY_1, 0);
+    addCache(simpleCache, KEY_1, 0, 15);
+    simpleCache.releaseHoleSpan(cacheSpan1);
+    // Write and remove data for KEY_2.
+    CacheSpan cacheSpan2 = simpleCache.startReadWrite(KEY_2, 0);
+    addCache(simpleCache, KEY_2, 0, 15);
+    simpleCache.releaseHoleSpan(cacheSpan2);
+    simpleCache.removeSpan(simpleCache.getCachedSpans(KEY_2).first());
+    // Don't release the cache. This means the index file wont have been written to disk after the
+    // data for KEY_2 was removed. Move the cache instead, so we can reload it without failing the
+    // folder locking check.
+    File cacheDir2 = Util.createTempFile(RuntimeEnvironment.application, "ExoPlayerTest");
+    cacheDir2.delete();
+    cacheDir.renameTo(cacheDir2);
+    // Reload the cache from its new location.
+    simpleCache = new SimpleCache(cacheDir2, new NoOpCacheEvictor());
+    // Read data back for KEY_1.
+    CacheSpan cacheSpan3 = simpleCache.startReadWrite(KEY_1, 0);
+    assertCachedDataReadCorrect(cacheSpan3);
+    // Check the entry for KEY_2 was removed when the cache was reloaded.
+    assertThat(simpleCache.getCachedSpans(KEY_2)).isEmpty();
+    Util.recursiveDelete(cacheDir2);
+  }
+  @Test
  public void testEncryptedIndex() throws Exception {
    byte[] key = "Bar12345Bar12345".getBytes(C.UTF8_NAME); // 128 bit key
    SimpleCache simpleCache = getEncryptedSimpleCache(key);

--- a/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaSource.java
+++ b/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaSource.java
@@ -26,6 +26,8 @@ import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.ExoPlayerLibraryInfo;
 import com.google.android.exoplayer2.ParserException;
 import com.google.android.exoplayer2.Timeline;
+import com.google.android.exoplayer2.offline.FilteringManifestParser;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.BaseMediaSource;
 import com.google.android.exoplayer2.source.CompositeSequenceableLoaderFactory;
 import com.google.android.exoplayer2.source.DefaultCompositeSequenceableLoaderFactory;
@@ -59,6 +61,7 @@ import java.io.InputStreamReader;
 import java.nio.charset.Charset;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
+import java.util.List;
 import java.util.Locale;
 import java.util.TimeZone;
 import java.util.regex.Matcher;
@@ -75,15 +78,16 @@ public final class DashMediaSource extends BaseMediaSource {
  public static final class Factory implements AdsMediaSource.MediaSourceFactory {
    private final DashChunkSource.Factory chunkSourceFactory;
-    private final @Nullable DataSource.Factory manifestDataSourceFactory;
+    @Nullable private final DataSource.Factory manifestDataSourceFactory;
-    private @Nullable ParsingLoadable.Parser<? extends DashManifest> manifestParser;
+    @Nullable private ParsingLoadable.Parser<? extends DashManifest> manifestParser;
+    @Nullable private List<StreamKey> streamKeys;
    private CompositeSequenceableLoaderFactory compositeSequenceableLoaderFactory;
    private LoadErrorHandlingPolicy loadErrorHandlingPolicy;
    private long livePresentationDelayMs;
    private boolean livePresentationDelayOverridesManifest;
    private boolean isCreateCalled;
-    private @Nullable Object tag;
+    @Nullable private Object tag;
    /**
     * Creates a new factory for {@link DashMediaSource}s.
@@ -211,6 +215,19 @@ public final class DashMediaSource extends BaseMediaSource {
    }
    /**
+     * Sets a list of {@link StreamKey stream keys} by which the manifest is filtered.
+     *
+     * @param streamKeys A list of {@link StreamKey stream keys}.
+     * @return This factory, for convenience.
+     * @throws IllegalStateException If one of the {@code create} methods has already been called.
+     */
+    public Factory setStreamKeys(List<StreamKey> streamKeys) {
+      Assertions.checkState(!isCreateCalled);
+      this.streamKeys = streamKeys;
+      return this;
+    }
+    /**
     * Sets the factory to create composite {@link SequenceableLoader}s for when this media source
     * loads data from multiple streams (video, audio etc...). The default is an instance of {@link
     * DefaultCompositeSequenceableLoaderFactory}.
@@ -240,6 +257,9 @@ public final class DashMediaSource extends BaseMediaSource {
    public DashMediaSource createMediaSource(DashManifest manifest) {
      Assertions.checkArgument(!manifest.dynamic);
      isCreateCalled = true;
+      if (streamKeys != null && !streamKeys.isEmpty()) {
+        manifest = manifest.copy(streamKeys);
+      }
      return new DashMediaSource(
          manifest,
          /* manifestUri= */ null,
@@ -281,6 +301,9 @@ public final class DashMediaSource extends BaseMediaSource {
      if (manifestParser == null) {
        manifestParser = new DashManifestParser();
      }
+      if (streamKeys != null) {
+        manifestParser = new FilteringManifestParser<>(manifestParser, streamKeys);
+      }
      return new DashMediaSource(
          /* manifest= */ null,
          Assertions.checkNotNull(manifestUri),

--- a/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadHelper.java
+++ b/library/dash/src/main/java/com/google/android/exoplayer2/source/dash/offline/DashDownloadHelper.java
@@ -16,22 +16,25 @@
 package com.google.android.exoplayer2.source.dash.offline;
 import android.net.Uri;
+import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
+import com.google.android.exoplayer2.RenderersFactory;
+import com.google.android.exoplayer2.drm.DrmSessionManager;
+import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
 import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloadHelper;
 import com.google.android.exoplayer2.offline.StreamKey;
-import com.google.android.exoplayer2.offline.TrackKey;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.source.dash.manifest.AdaptationSet;
 import com.google.android.exoplayer2.source.dash.manifest.DashManifest;
 import com.google.android.exoplayer2.source.dash.manifest.DashManifestParser;
 import com.google.android.exoplayer2.source.dash.manifest.Representation;
+import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.ParsingLoadable;
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.List;
 /** A {@link DownloadHelper} for DASH streams. */
@@ -39,8 +42,52 @@ public final class DashDownloadHelper extends DownloadHelper<DashManifest> {
  private final DataSource.Factory manifestDataSourceFactory;
-  public DashDownloadHelper(Uri uri, DataSource.Factory manifestDataSourceFactory) {
+  /**
-    super(DownloadAction.TYPE_DASH, uri, /* cacheKey= */ null);
+   * Creates a DASH download helper.
+   *
+   * <p>The helper uses {@link DownloadHelper#DEFAULT_TRACK_SELECTOR_PARAMETERS} for track selection
+   * and does not support drm protected content.
+   *
+   * @param uri A manifest {@link Uri}.
+   * @param manifestDataSourceFactory A {@link DataSource.Factory} used to load the manifest.
+   * @param renderersFactory The {@link RenderersFactory} creating the renderers for which tracks
+   *     are selected.
+   */
+  public DashDownloadHelper(
+      Uri uri, DataSource.Factory manifestDataSourceFactory, RenderersFactory renderersFactory) {
+    this(
+        uri,
+        manifestDataSourceFactory,
+        DownloadHelper.DEFAULT_TRACK_SELECTOR_PARAMETERS,
+        renderersFactory,
+        /* drmSessionManager= */ null);
+  }
+  /**
+   * Creates a DASH download helper.
+   *
+   * @param uri A manifest {@link Uri}.
+   * @param manifestDataSourceFactory A {@link DataSource.Factory} used to load the manifest.
+   * @param trackSelectorParameters {@link DefaultTrackSelector.Parameters} for selecting tracks for
+   *     downloading.
+   * @param renderersFactory The {@link RenderersFactory} creating the renderers for which tracks
+   *     are selected.
+   * @param drmSessionManager An optional {@link DrmSessionManager} used by the renderers created by
+   *     {@code renderersFactory}.
+   */
+  public DashDownloadHelper(
+      Uri uri,
+      DataSource.Factory manifestDataSourceFactory,
+      DefaultTrackSelector.Parameters trackSelectorParameters,
+      RenderersFactory renderersFactory,
+      @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager) {
+    super(
+        DownloadAction.TYPE_DASH,
+        uri,
+        /* cacheKey= */ null,
+        trackSelectorParameters,
+        renderersFactory,
+        drmSessionManager);
    this.manifestDataSourceFactory = manifestDataSourceFactory;
  }
@@ -72,12 +119,8 @@ public final class DashDownloadHelper extends DownloadHelper<DashManifest> {
  }
  @Override
-  protected List<StreamKey> toStreamKeys(List<TrackKey> trackKeys) {
+  protected StreamKey toStreamKey(
-    List<StreamKey> streamKeys = new ArrayList<>(trackKeys.size());
+      int periodIndex, int trackGroupIndex, int trackIndexInTrackGroup) {
-    for (int i = 0; i < trackKeys.size(); i++) {
+    return new StreamKey(periodIndex, trackGroupIndex, trackIndexInTrackGroup);
-      TrackKey trackKey = trackKeys.get(i);
-      streamKeys.add(new StreamKey(trackKey.periodIndex, trackKey.groupIndex, trackKey.trackIndex));
-    }
-    return streamKeys;
  }
 }
--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaSource.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaSource.java
@@ -22,6 +22,7 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.ExoPlayerLibraryInfo;
 import com.google.android.exoplayer2.extractor.Extractor;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.BaseMediaSource;
 import com.google.android.exoplayer2.source.CompositeSequenceableLoaderFactory;
 import com.google.android.exoplayer2.source.DefaultCompositeSequenceableLoaderFactory;
@@ -34,6 +35,7 @@ import com.google.android.exoplayer2.source.SinglePeriodTimeline;
 import com.google.android.exoplayer2.source.ads.AdsMediaSource;
 import com.google.android.exoplayer2.source.hls.playlist.DefaultHlsPlaylistParserFactory;
 import com.google.android.exoplayer2.source.hls.playlist.DefaultHlsPlaylistTracker;
+import com.google.android.exoplayer2.source.hls.playlist.FilteringHlsPlaylistParserFactory;
 import com.google.android.exoplayer2.source.hls.playlist.HlsMediaPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylistParser;
@@ -64,12 +66,13 @@ public final class HlsMediaSource extends BaseMediaSource
    private HlsExtractorFactory extractorFactory;
    private HlsPlaylistParserFactory playlistParserFactory;
+    @Nullable private List<StreamKey> streamKeys;
    private HlsPlaylistTracker.Factory playlistTrackerFactory;
    private CompositeSequenceableLoaderFactory compositeSequenceableLoaderFactory;
    private LoadErrorHandlingPolicy loadErrorHandlingPolicy;
    private boolean allowChunklessPreparation;
    private boolean isCreateCalled;
-    private @Nullable Object tag;
+    @Nullable private Object tag;
    /**
     * Creates a new factory for {@link HlsMediaSource}s.
@@ -164,8 +167,8 @@ public final class HlsMediaSource extends BaseMediaSource
    }
    /**
-     * Sets the factory from which playlist parsers will be obtained. The default value is created
+     * Sets the factory from which playlist parsers will be obtained. The default value is a {@link
-     * by calling {@link DefaultHlsPlaylistParserFactory#DefaultHlsPlaylistParserFactory()}.
+     * DefaultHlsPlaylistParserFactory}.
     *
     * @param playlistParserFactory An {@link HlsPlaylistParserFactory}.
     * @return This factory, for convenience.
@@ -178,6 +181,19 @@ public final class HlsMediaSource extends BaseMediaSource
    }
    /**
+     * Sets a list of {@link StreamKey stream keys} by which the playlists are filtered.
+     *
+     * @param streamKeys A list of {@link StreamKey stream keys}.
+     * @return This factory, for convenience.
+     * @throws IllegalStateException If one of the {@code create} methods has already been called.
+     */
+    public Factory setStreamKeys(List<StreamKey> streamKeys) {
+      Assertions.checkState(!isCreateCalled);
+      this.streamKeys = streamKeys;
+      return this;
+    }
+    /**
     * Sets the {@link HlsPlaylistTracker} factory. The default value is {@link
     * DefaultHlsPlaylistTracker#FACTORY}.
     *
@@ -232,6 +248,10 @@ public final class HlsMediaSource extends BaseMediaSource
    @Override
    public HlsMediaSource createMediaSource(Uri playlistUri) {
      isCreateCalled = true;
+      if (streamKeys != null) {
+        playlistParserFactory =
+            new FilteringHlsPlaylistParserFactory(playlistParserFactory, streamKeys);
+      }
      return new HlsMediaSource(
          playlistUri,
          hlsDataSourceFactory,

--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadHelper.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/offline/HlsDownloadHelper.java
@@ -16,23 +16,26 @@
 package com.google.android.exoplayer2.source.hls.offline;
 import android.net.Uri;
+import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
+import com.google.android.exoplayer2.RenderersFactory;
+import com.google.android.exoplayer2.drm.DrmSessionManager;
+import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
 import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloadHelper;
 import com.google.android.exoplayer2.offline.StreamKey;
-import com.google.android.exoplayer2.offline.TrackKey;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.source.hls.playlist.HlsMasterPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsMediaPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylist;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylistParser;
+import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.ParsingLoadable;
 import com.google.android.exoplayer2.util.Assertions;
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -43,8 +46,52 @@ public final class HlsDownloadHelper extends DownloadHelper<HlsPlaylist> {
  private int[] renditionGroups;
-  public HlsDownloadHelper(Uri uri, DataSource.Factory manifestDataSourceFactory) {
+  /**
-    super(DownloadAction.TYPE_HLS, uri, /* cacheKey= */ null);
+   * Creates a HLS download helper.
+   *
+   * <p>The helper uses {@link DownloadHelper#DEFAULT_TRACK_SELECTOR_PARAMETERS} for track selection
+   * and does not support drm protected content.
+   *
+   * @param uri A manifest {@link Uri}.
+   * @param manifestDataSourceFactory A {@link DataSource.Factory} used to load the manifest.
+   * @param renderersFactory The {@link RenderersFactory} creating the renderers for which tracks
+   *     are selected.
+   */
+  public HlsDownloadHelper(
+      Uri uri, DataSource.Factory manifestDataSourceFactory, RenderersFactory renderersFactory) {
+    this(
+        uri,
+        manifestDataSourceFactory,
+        DownloadHelper.DEFAULT_TRACK_SELECTOR_PARAMETERS,
+        renderersFactory,
+        /* drmSessionManager= */ null);
+  }
+  /**
+   * Creates a HLS download helper.
+   *
+   * @param uri A manifest {@link Uri}.
+   * @param manifestDataSourceFactory A {@link DataSource.Factory} used to load the manifest.
+   * @param trackSelectorParameters {@link DefaultTrackSelector.Parameters} for selecting tracks for
+   *     downloading.
+   * @param renderersFactory The {@link RenderersFactory} creating the renderers for which tracks
+   *     are selected.
+   * @param drmSessionManager An optional {@link DrmSessionManager} used by the renderers created by
+   *     {@code renderersFactory}.
+   */
+  public HlsDownloadHelper(
+      Uri uri,
+      DataSource.Factory manifestDataSourceFactory,
+      DefaultTrackSelector.Parameters trackSelectorParameters,
+      RenderersFactory renderersFactory,
+      @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager) {
+    super(
+        DownloadAction.TYPE_HLS,
+        uri,
+        /* cacheKey= */ null,
+        trackSelectorParameters,
+        renderersFactory,
+        drmSessionManager);
    this.manifestDataSourceFactory = manifestDataSourceFactory;
  }
@@ -61,7 +108,7 @@ public final class HlsDownloadHelper extends DownloadHelper<HlsPlaylist> {
      renditionGroups = new int[0];
      return new TrackGroupArray[] {TrackGroupArray.EMPTY};
    }
-    // TODO: Generate track groups as in playback. Reverse the mapping in getDownloadAction.
+    // TODO: Generate track groups as in playback. Reverse the mapping in toStreamKey.
    HlsMasterPlaylist masterPlaylist = (HlsMasterPlaylist) playlist;
    TrackGroup[] trackGroups = new TrackGroup[3];
    renditionGroups = new int[3];
@@ -82,14 +129,9 @@ public final class HlsDownloadHelper extends DownloadHelper<HlsPlaylist> {
  }
  @Override
-  protected List<StreamKey> toStreamKeys(List<TrackKey> trackKeys) {
+  protected StreamKey toStreamKey(
-    List<StreamKey> representationKeys = new ArrayList<>(trackKeys.size());
+      int periodIndex, int trackGroupIndex, int trackIndexInTrackGroup) {
-    for (int i = 0; i < trackKeys.size(); i++) {
+    return new StreamKey(renditionGroups[trackGroupIndex], trackIndexInTrackGroup);
-      TrackKey trackKey = trackKeys.get(i);
-      representationKeys.add(
-          new StreamKey(renditionGroups[trackKey.groupIndex], trackKey.trackIndex));
-    }
-    return representationKeys;
  }
  private static Format[] toFormats(List<HlsMasterPlaylist.HlsUrl> hlsUrls) {

--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/DefaultHlsPlaylistParserFactory.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/DefaultHlsPlaylistParserFactory.java
@@ -15,40 +15,19 @@
 */
 package com.google.android.exoplayer2.source.hls.playlist;
-import com.google.android.exoplayer2.offline.FilteringManifestParser;
-import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.upstream.ParsingLoadable;
-import java.util.Collections;
-import java.util.List;
 /** Default implementation for {@link HlsPlaylistParserFactory}. */
 public final class DefaultHlsPlaylistParserFactory implements HlsPlaylistParserFactory {
-  private final List<StreamKey> streamKeys;
-  /** Creates an instance that does not filter any parsing results. */
-  public DefaultHlsPlaylistParserFactory() {
-    this(Collections.emptyList());
-  }
-  /**
-   * Creates an instance that filters the parsing results using the given {@code streamKeys}.
-   *
-   * @param streamKeys See {@link
-   *     FilteringManifestParser#FilteringManifestParser(ParsingLoadable.Parser, List)}.
-   */
-  public DefaultHlsPlaylistParserFactory(List<StreamKey> streamKeys) {
-    this.streamKeys = streamKeys;
-  }
  @Override
  public ParsingLoadable.Parser<HlsPlaylist> createPlaylistParser() {
-    return new FilteringManifestParser<>(new HlsPlaylistParser(), streamKeys);
+    return new HlsPlaylistParser();
  }
  @Override
  public ParsingLoadable.Parser<HlsPlaylist> createPlaylistParser(
      HlsMasterPlaylist masterPlaylist) {
-    return new FilteringManifestParser<>(new HlsPlaylistParser(masterPlaylist), streamKeys);
+    return new HlsPlaylistParser(masterPlaylist);
  }
 }
--- a/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/FilteringHlsPlaylistParserFactory.java
+++ b/library/hls/src/main/java/com/google/android/exoplayer2/source/hls/playlist/FilteringHlsPlaylistParserFactory.java
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.android.exoplayer2.source.hls.playlist;
+import com.google.android.exoplayer2.offline.FilteringManifestParser;
+import com.google.android.exoplayer2.offline.StreamKey;
+import com.google.android.exoplayer2.upstream.ParsingLoadable;
+import java.util.List;
+/**
+ * A {@link HlsPlaylistParserFactory} that includes only the streams identified by the given stream
+ * keys.
+ */
+public final class FilteringHlsPlaylistParserFactory implements HlsPlaylistParserFactory {
+  private final HlsPlaylistParserFactory hlsPlaylistParserFactory;
+  private final List<StreamKey> streamKeys;
+  /**
+   * @param hlsPlaylistParserFactory A factory for the parsers of the playlists which will be
+   *     filtered.
+   * @param streamKeys The stream keys. If null or empty then filtering will not occur.
+   */
+  public FilteringHlsPlaylistParserFactory(
+      HlsPlaylistParserFactory hlsPlaylistParserFactory, List<StreamKey> streamKeys) {
+    this.hlsPlaylistParserFactory = hlsPlaylistParserFactory;
+    this.streamKeys = streamKeys;
+  }
+  @Override
+  public ParsingLoadable.Parser<HlsPlaylist> createPlaylistParser() {
+    return new FilteringManifestParser<>(
+        hlsPlaylistParserFactory.createPlaylistParser(), streamKeys);
+  }
+  @Override
+  public ParsingLoadable.Parser<HlsPlaylist> createPlaylistParser(
+      HlsMasterPlaylist masterPlaylist) {
+    return new FilteringManifestParser<>(
+        hlsPlaylistParserFactory.createPlaylistParser(masterPlaylist), streamKeys);
+  }
+}
--- a/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaPeriod.java
+++ b/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaPeriod.java
@@ -20,6 +20,7 @@ import android.util.Base64;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.SeekParameters;
 import com.google.android.exoplayer2.extractor.mp4.TrackEncryptionBox;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.CompositeSequenceableLoaderFactory;
 import com.google.android.exoplayer2.source.MediaPeriod;
 import com.google.android.exoplayer2.source.MediaSourceEventListener.EventDispatcher;
@@ -37,12 +38,11 @@ import com.google.android.exoplayer2.upstream.LoaderErrorThrower;
 import com.google.android.exoplayer2.upstream.TransferListener;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.List;
-/**
+/** A SmoothStreaming {@link MediaPeriod}. */
- * A SmoothStreaming {@link MediaPeriod}.
+/* package */ final class SsMediaPeriod
- */
+    implements MediaPeriod, SequenceableLoader.Callback<ChunkSampleStream<SsChunkSource>> {
-/* package */ final class SsMediaPeriod implements MediaPeriod,
-    SequenceableLoader.Callback<ChunkSampleStream<SsChunkSource>> {
  private static final int INITIALIZATION_VECTOR_SIZE = 8;
@@ -112,6 +112,8 @@ import java.util.ArrayList;
    eventDispatcher.mediaPeriodReleased();
  }
+  // MediaPeriod implementation.
  @Override
  public void prepare(Callback callback, long positionUs) {
    this.callback = callback;
@@ -158,6 +160,16 @@ import java.util.ArrayList;
  }
  @Override
+  public List<StreamKey> getStreamKeys(TrackSelection trackSelection) {
+    List<StreamKey> streamKeys = new ArrayList<>(trackSelection.length());
+    int streamElementIndex = trackGroups.indexOf(trackSelection.getTrackGroup());
+    for (int i = 0; i < trackSelection.length(); i++) {
+      streamKeys.add(new StreamKey(streamElementIndex, trackSelection.getIndexInTrackGroup(i)));
+    }
+    return streamKeys;
+  }
+  @Override
  public void discardBuffer(long positionUs, boolean toKeyframe) {
    for (ChunkSampleStream<SsChunkSource> sampleStream : sampleStreams) {
      sampleStream.discardBuffer(positionUs, toKeyframe);
@@ -211,7 +223,7 @@ import java.util.ArrayList;
    return positionUs;
  }
-  // SequenceableLoader.Callback implementation
+  // SequenceableLoader.Callback implementation.
  @Override
  public void onContinueLoadingRequested(ChunkSampleStream<SsChunkSource> sampleStream) {
@@ -277,5 +289,4 @@ import java.util.ArrayList;
    data[firstPosition] = data[secondPosition];
    data[secondPosition] = temp;
  }
 }
--- a/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaSource.java
+++ b/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaSource.java
@@ -24,6 +24,8 @@ import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.ExoPlayerLibraryInfo;
 import com.google.android.exoplayer2.ParserException;
 import com.google.android.exoplayer2.Timeline;
+import com.google.android.exoplayer2.offline.FilteringManifestParser;
+import com.google.android.exoplayer2.offline.StreamKey;
 import com.google.android.exoplayer2.source.BaseMediaSource;
 import com.google.android.exoplayer2.source.CompositeSequenceableLoaderFactory;
 import com.google.android.exoplayer2.source.DefaultCompositeSequenceableLoaderFactory;
@@ -50,6 +52,7 @@ import com.google.android.exoplayer2.upstream.TransferListener;
 import com.google.android.exoplayer2.util.Assertions;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.List;
 /** A SmoothStreaming {@link MediaSource}. */
 public final class SsMediaSource extends BaseMediaSource
@@ -63,14 +66,15 @@ public final class SsMediaSource extends BaseMediaSource
  public static final class Factory implements AdsMediaSource.MediaSourceFactory {
    private final SsChunkSource.Factory chunkSourceFactory;
-    private final @Nullable DataSource.Factory manifestDataSourceFactory;
+    @Nullable private final DataSource.Factory manifestDataSourceFactory;
-    private @Nullable ParsingLoadable.Parser<? extends SsManifest> manifestParser;
+    @Nullable private ParsingLoadable.Parser<? extends SsManifest> manifestParser;
+    @Nullable private List<StreamKey> streamKeys;
    private CompositeSequenceableLoaderFactory compositeSequenceableLoaderFactory;
    private LoadErrorHandlingPolicy loadErrorHandlingPolicy;
    private long livePresentationDelayMs;
    private boolean isCreateCalled;
-    private @Nullable Object tag;
+    @Nullable private Object tag;
    /**
     * Creates a new factory for {@link SsMediaSource}s.
@@ -179,6 +183,19 @@ public final class SsMediaSource extends BaseMediaSource
    }
    /**
+     * Sets a list of {@link StreamKey stream keys} by which the manifest is filtered.
+     *
+     * @param streamKeys A list of {@link StreamKey stream keys}.
+     * @return This factory, for convenience.
+     * @throws IllegalStateException If one of the {@code create} methods has already been called.
+     */
+    public Factory setStreamKeys(List<StreamKey> streamKeys) {
+      Assertions.checkState(!isCreateCalled);
+      this.streamKeys = streamKeys;
+      return this;
+    }
+    /**
     * Sets the factory to create composite {@link SequenceableLoader}s for when this media source
     * loads data from multiple streams (video, audio etc.). The default is an instance of {@link
     * DefaultCompositeSequenceableLoaderFactory}.
@@ -208,6 +225,9 @@ public final class SsMediaSource extends BaseMediaSource
    public SsMediaSource createMediaSource(SsManifest manifest) {
      Assertions.checkArgument(!manifest.isLive);
      isCreateCalled = true;
+      if (streamKeys != null && !streamKeys.isEmpty()) {
+        manifest = manifest.copy(streamKeys);
+      }
      return new SsMediaSource(
          manifest,
          /* manifestUri= */ null,
@@ -248,6 +268,9 @@ public final class SsMediaSource extends BaseMediaSource
      if (manifestParser == null) {
        manifestParser = new SsManifestParser();
      }
+      if (streamKeys != null) {
+        manifestParser = new FilteringManifestParser<>(manifestParser, streamKeys);
+      }
      return new SsMediaSource(
          /* manifest= */ null,
          Assertions.checkNotNull(manifestUri),

--- a/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadHelper.java
+++ b/library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/offline/SsDownloadHelper.java
@@ -16,35 +16,83 @@
 package com.google.android.exoplayer2.source.smoothstreaming.offline;
 import android.net.Uri;
+import android.support.annotation.Nullable;
 import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.RenderersFactory;
+import com.google.android.exoplayer2.drm.DrmSessionManager;
+import com.google.android.exoplayer2.drm.FrameworkMediaCrypto;
 import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloadHelper;
 import com.google.android.exoplayer2.offline.StreamKey;
-import com.google.android.exoplayer2.offline.TrackKey;
 import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifest;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifestParser;
+import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsUtil;
+import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.ParsingLoadable;
 import java.io.IOException;
-import java.util.ArrayList;
-import java.util.List;
 /** A {@link DownloadHelper} for SmoothStreaming streams. */
 public final class SsDownloadHelper extends DownloadHelper<SsManifest> {
  private final DataSource.Factory manifestDataSourceFactory;
-  public SsDownloadHelper(Uri uri, DataSource.Factory manifestDataSourceFactory) {
+  /**
-    super(DownloadAction.TYPE_SS, uri, /* cacheKey= */ null);
+   * Creates a SmoothStreaming download helper.
+   *
+   * <p>The helper uses {@link DownloadHelper#DEFAULT_TRACK_SELECTOR_PARAMETERS} for track selection
+   * and does not support drm protected content.
+   *
+   * @param uri A manifest {@link Uri}.
+   * @param manifestDataSourceFactory A {@link DataSource.Factory} used to load the manifest.
+   * @param renderersFactory The {@link RenderersFactory} creating the renderers for which tracks
+   *     are selected.
+   */
+  public SsDownloadHelper(
+      Uri uri, DataSource.Factory manifestDataSourceFactory, RenderersFactory renderersFactory) {
+    this(
+        uri,
+        manifestDataSourceFactory,
+        DownloadHelper.DEFAULT_TRACK_SELECTOR_PARAMETERS,
+        renderersFactory,
+        /* drmSessionManager= */ null);
+  }
+  /**
+   * Creates a SmoothStreaming download helper.
+   *
+   * @param uri A manifest {@link Uri}.
+   * @param manifestDataSourceFactory A {@link DataSource.Factory} used to load the manifest.
+   * @param trackSelectorParameters {@link DefaultTrackSelector.Parameters} for selecting tracks for
+   *     downloading.
+   * @param renderersFactory The {@link RenderersFactory} creating the renderers for which tracks
+   *     are selected.
+   * @param drmSessionManager An optional {@link DrmSessionManager} used by the renderers created by
+   *     {@code renderersFactory}.
+   */
+  public SsDownloadHelper(
+      Uri uri,
+      DataSource.Factory manifestDataSourceFactory,
+      DefaultTrackSelector.Parameters trackSelectorParameters,
+      RenderersFactory renderersFactory,
+      @Nullable DrmSessionManager<FrameworkMediaCrypto> drmSessionManager) {
+    super(
+        DownloadAction.TYPE_SS,
+        uri,
+        /* cacheKey= */ null,
+        trackSelectorParameters,
+        renderersFactory,
+        drmSessionManager);
    this.manifestDataSourceFactory = manifestDataSourceFactory;
  }
  @Override
  protected SsManifest loadManifest(Uri uri) throws IOException {
    DataSource dataSource = manifestDataSourceFactory.createDataSource();
-    return ParsingLoadable.load(dataSource, new SsManifestParser(), uri, C.DATA_TYPE_MANIFEST);
+    Uri fixedUri = SsUtil.fixManifestUri(uri);
+    return ParsingLoadable.load(dataSource, new SsManifestParser(), fixedUri, C.DATA_TYPE_MANIFEST);
  }
  @Override
@@ -58,12 +106,8 @@ public final class SsDownloadHelper extends DownloadHelper<SsManifest> {
  }
  @Override
-  protected List<StreamKey> toStreamKeys(List<TrackKey> trackKeys) {
+  protected StreamKey toStreamKey(
-    List<StreamKey> representationKeys = new ArrayList<>(trackKeys.size());
+      int periodIndex, int trackGroupIndex, int trackIndexInTrackGroup) {
-    for (int i = 0; i < trackKeys.size(); i++) {
+    return new StreamKey(trackGroupIndex, trackIndexInTrackGroup);
-      TrackKey trackKey = trackKeys.get(i);
-      representationKeys.add(new StreamKey(trackKey.groupIndex, trackKey.trackIndex));
-    }
-    return representationKeys;
  }
 }
--- a/library/ui/src/main/java/com/google/android/exoplayer2/ui/DownloadNotificationUtil.java
+++ b/library/ui/src/main/java/com/google/android/exoplayer2/ui/DownloadNotificationUtil.java
@@ -23,7 +23,7 @@ import android.support.annotation.Nullable;
 import android.support.annotation.StringRes;
 import android.support.v4.app.NotificationCompat;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.offline.DownloadManager.TaskState;
+import com.google.android.exoplayer2.offline.DownloadManager.DownloadState;
 /** Helper for creating download notifications. */
 public final class DownloadNotificationUtil {
@@ -33,7 +33,7 @@ public final class DownloadNotificationUtil {
  private DownloadNotificationUtil() {}
  /**
-   * Returns a progress notification for the given task states.
+   * Returns a progress notification for the given download states.
   *
   * @param context A context for accessing resources.
   * @param smallIcon A small icon for the notification.
@@ -41,7 +41,7 @@ public final class DownloadNotificationUtil {
   *     above.
   * @param contentIntent An optional content intent to send when the notification is clicked.
   * @param message An optional message to display on the notification.
-   * @param taskStates The task states.
+   * @param downloadStates The download states.
   * @return The notification.
   */
  public static Notification buildProgressNotification(
@@ -50,28 +50,28 @@ public final class DownloadNotificationUtil {
      String channelId,
      @Nullable PendingIntent contentIntent,
      @Nullable String message,
-      TaskState[] taskStates) {
+      DownloadState[] downloadStates) {
    float totalPercentage = 0;
    int downloadTaskCount = 0;
    boolean allDownloadPercentagesUnknown = true;
    boolean haveDownloadedBytes = false;
    boolean haveDownloadTasks = false;
    boolean haveRemoveTasks = false;
-    for (TaskState taskState : taskStates) {
+    for (DownloadState downloadState : downloadStates) {
-      if (taskState.state != TaskState.STATE_STARTED
+      if (downloadState.state != DownloadState.STATE_STARTED
-          && taskState.state != TaskState.STATE_COMPLETED) {
+          && downloadState.state != DownloadState.STATE_COMPLETED) {
        continue;
      }
-      if (taskState.action.isRemoveAction) {
+      if (downloadState.action.isRemoveAction) {
        haveRemoveTasks = true;
        continue;
      }
      haveDownloadTasks = true;
-      if (taskState.downloadPercentage != C.PERCENTAGE_UNSET) {
+      if (downloadState.downloadPercentage != C.PERCENTAGE_UNSET) {
        allDownloadPercentagesUnknown = false;
-        totalPercentage += taskState.downloadPercentage;
+        totalPercentage += downloadState.downloadPercentage;
      }
-      haveDownloadedBytes |= taskState.downloadedBytes > 0;
+      haveDownloadedBytes |= downloadState.downloadedBytes > 0;
      downloadTaskCount++;
    }

--- a/library/ui/src/main/java/com/google/android/exoplayer2/ui/PlayerView.java
+++ b/library/ui/src/main/java/com/google/android/exoplayer2/ui/PlayerView.java
@@ -29,7 +29,6 @@ import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
 import android.os.Looper;
 import android.support.annotation.IntDef;
-import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v4.content.ContextCompat;
 import android.util.AttributeSet;
@@ -187,8 +186,9 @@ import java.util.List;
 *         <li>Type: {@link AspectRatioFrameLayout}
 *       </ul>
 *   <li><b>{@code exo_shutter}</b> - A view that's made visible when video should be hidden. This
- *       view is typically an opaque view that covers the video surface view, thereby obscuring it
+ *       view is typically an opaque view that covers the video surface, thereby obscuring it when
- *       when visible.
+ *       visible. Obscuring the surface in this way also helps to prevent flicker at the start of
+ *       playback when {@code surface_type="surface_view"}.
 *       <ul>
 *         <li>Type: {@link View}
 *       </ul>
@@ -271,13 +271,13 @@ public class PlayerView extends FrameLayout {
  private static final int SURFACE_TYPE_MONO360_VIEW = 3;
  // LINT.ThenChange(../../../../../../res/values/attrs.xml)
-  private final AspectRatioFrameLayout contentFrame;
+  @Nullable private final AspectRatioFrameLayout contentFrame;
  private final View shutterView;
-  private final View surfaceView;
+  @Nullable private final View surfaceView;
  private final ImageView artworkView;
  private final SubtitleView subtitleView;
-  private final @Nullable View bufferingView;
+  @Nullable private final View bufferingView;
-  private final @Nullable TextView errorMessageView;
+  @Nullable private final TextView errorMessageView;
  private final PlayerControlView controller;
  private final ComponentListener componentListener;
  private final FrameLayout overlayFrameLayout;
@@ -285,11 +285,11 @@ public class PlayerView extends FrameLayout {
  private Player player;
  private boolean useController;
  private boolean useArtwork;
-  private @Nullable Drawable defaultArtwork;
+  @Nullable private Drawable defaultArtwork;
  private @ShowBuffering int showBuffering;
  private boolean keepContentOnPlayerReset;
-  private @Nullable ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider;
+  @Nullable private ErrorMessageProvider<? super ExoPlaybackException> errorMessageProvider;
-  private @Nullable CharSequence customErrorMessage;
+  @Nullable private CharSequence customErrorMessage;
  private int controllerShowTimeoutMs;
  private boolean controllerAutoShow;
  private boolean controllerHideDuringAds;
@@ -474,9 +474,7 @@ public class PlayerView extends FrameLayout {
   * @param newPlayerView The new view to attach to the player.
   */
  public static void switchTargetView(
-      @NonNull Player player,
+      Player player, @Nullable PlayerView oldPlayerView, @Nullable PlayerView newPlayerView) {
-      @Nullable PlayerView oldPlayerView,
-      @Nullable PlayerView newPlayerView) {
    if (oldPlayerView == newPlayerView) {
      return;
    }
@@ -1080,6 +1078,26 @@ public class PlayerView extends FrameLayout {
    }
  }
+  /**
+   * Called when there's a change in the aspect ratio of the content being displayed. The default
+   * implementation sets the aspect ratio of the content frame to that of the content, unless the
+   * content view is a {@link SphericalSurfaceView} in which case the frame's aspect ratio is
+   * cleared.
+   *
+   * @param contentAspectRatio The aspect ratio of the content.
+   * @param contentFrame The content frame, or {@code null}.
+   * @param contentView The view that holds the content being displayed, or {@code null}.
+   */
+  protected void onContentAspectRatioChanged(
+      float contentAspectRatio,
+      @Nullable AspectRatioFrameLayout contentFrame,
+      @Nullable View contentView) {
+    if (contentFrame != null) {
+      contentFrame.setAspectRatio(
+          contentView instanceof SphericalSurfaceView ? 0 : contentAspectRatio);
+    }
+  }
  private boolean toggleControllerVisibility() {
    if (!useController || player == null) {
      return false;
@@ -1193,9 +1211,8 @@ public class PlayerView extends FrameLayout {
      int drawableWidth = drawable.getIntrinsicWidth();
      int drawableHeight = drawable.getIntrinsicHeight();
      if (drawableWidth > 0 && drawableHeight > 0) {
-        if (contentFrame != null) {
+        float artworkAspectRatio = (float) drawableWidth / drawableHeight;
-          contentFrame.setAspectRatio((float) drawableWidth / drawableHeight);
+        onContentAspectRatioChanged(artworkAspectRatio, contentFrame, artworkView);
-        }
        artworkView.setImageDrawable(drawable);
        artworkView.setVisibility(VISIBLE);
        return true;
@@ -1328,9 +1345,6 @@ public class PlayerView extends FrameLayout {
    @Override
    public void onVideoSizeChanged(
        int width, int height, int unappliedRotationDegrees, float pixelWidthHeightRatio) {
-      if (contentFrame == null) {
-        return;
-      }
      float videoAspectRatio =
          (height == 0 || width == 0) ? 1 : (width * pixelWidthHeightRatio) / height;
@@ -1351,11 +1365,9 @@ public class PlayerView extends FrameLayout {
          surfaceView.addOnLayoutChangeListener(this);
        }
        applyTextureViewRotation((TextureView) surfaceView, textureViewRotation);
-      } else if (surfaceView instanceof SphericalSurfaceView) {
-        videoAspectRatio = 0;
      }
-      contentFrame.setAspectRatio(videoAspectRatio);
+      onContentAspectRatioChanged(videoAspectRatio, contentFrame, surfaceView);
    }
    @Override

--- a/library/ui/src/main/java/com/google/android/exoplayer2/ui/TrackSelectionView.java
+++ b/library/ui/src/main/java/com/google/android/exoplayer2/ui/TrackSelectionView.java
@@ -15,7 +15,6 @@
 */
 package com.google.android.exoplayer2.ui;
-import android.app.Activity;
 import android.app.AlertDialog;
 import android.app.Dialog;
 import android.content.Context;
@@ -33,13 +32,25 @@ import com.google.android.exoplayer2.source.TrackGroup;
 import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 import com.google.android.exoplayer2.trackselection.DefaultTrackSelector.SelectionOverride;
-import com.google.android.exoplayer2.trackselection.MappingTrackSelector;
+import com.google.android.exoplayer2.trackselection.MappingTrackSelector.MappedTrackInfo;
 import com.google.android.exoplayer2.util.Assertions;
 import java.util.Arrays;
+import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 /** A view for making track selections. */
 public class TrackSelectionView extends LinearLayout {
+  /** Callback which is invoked when a track selection has been made. */
+  public interface DialogCallback {
+    /**
+     * Called when track are selected.
+     *
+     * @param parameters The {@link DefaultTrackSelector.Parameters} for the selected tracks.
+     */
+    void onTracksSelected(DefaultTrackSelector.Parameters parameters);
+  }
  private final int selectableItemBackgroundResourceId;
  private final LayoutInflater inflater;
  private final CheckedTextView disableView;
@@ -51,35 +62,64 @@ public class TrackSelectionView extends LinearLayout {
  private TrackNameProvider trackNameProvider;
  private CheckedTextView[][] trackViews;
-  private DefaultTrackSelector trackSelector;
+  private @MonotonicNonNull MappedTrackInfo mappedTrackInfo;
  private int rendererIndex;
+  private DefaultTrackSelector.Parameters parameters;
  private TrackGroupArray trackGroups;
  private boolean isDisabled;
-  private @Nullable SelectionOverride override;
+  @Nullable private SelectionOverride override;
  /**
   * Gets a pair consisting of a dialog and the {@link TrackSelectionView} that will be shown by it.
   *
-   * @param activity The parent activity.
+   * <p>The dialog shows the current configuration of the provided {@code TrackSelector} and updates
+   * the parameters when closing the dialog.
+   *
+   * @param context The parent context.
   * @param title The dialog's title.
   * @param trackSelector The track selector.
   * @param rendererIndex The index of the renderer.
   * @return The dialog and the {@link TrackSelectionView} that will be shown by it.
   */
  public static Pair<AlertDialog, TrackSelectionView> getDialog(
-      Activity activity,
+      Context context, CharSequence title, DefaultTrackSelector trackSelector, int rendererIndex) {
+    return getDialog(
+        context,
+        title,
+        Assertions.checkNotNull(trackSelector.getCurrentMappedTrackInfo()),
+        rendererIndex,
+        trackSelector.getParameters(),
+        trackSelector::setParameters);
+  }
+  /**
+   * Gets a pair consisting of a dialog and the {@link TrackSelectionView} that will be shown by it.
+   *
+   * @param context The parent context.
+   * @param title The dialog's title.
+   * @param mappedTrackInfo The {@link MappedTrackInfo}.
+   * @param rendererIndex The index of the renderer.
+   * @param parameters The {@link DefaultTrackSelector.Parameters}.
+   * @param callback The {@link DialogCallback} invoked when the dialog is closed successfully.
+   * @return The dialog and the {@link TrackSelectionView} that will be shown by it.
+   */
+  public static Pair<AlertDialog, TrackSelectionView> getDialog(
+      Context context,
      CharSequence title,
-      DefaultTrackSelector trackSelector,
+      MappedTrackInfo mappedTrackInfo,
-      int rendererIndex) {
+      int rendererIndex,
-    AlertDialog.Builder builder = new AlertDialog.Builder(activity);
+      DefaultTrackSelector.Parameters parameters,
+      DialogCallback callback) {
+    AlertDialog.Builder builder = new AlertDialog.Builder(context);
    // Inflate with the builder's context to ensure the correct style is used.
    LayoutInflater dialogInflater = LayoutInflater.from(builder.getContext());
    View dialogView = dialogInflater.inflate(R.layout.exo_track_selection_dialog, null);
-    final TrackSelectionView selectionView = dialogView.findViewById(R.id.exo_track_selection_view);
+    TrackSelectionView selectionView = dialogView.findViewById(R.id.exo_track_selection_view);
-    selectionView.init(trackSelector, rendererIndex);
+    selectionView.init(mappedTrackInfo, rendererIndex, parameters);
-    Dialog.OnClickListener okClickListener = (dialog, which) -> selectionView.applySelection();
+    Dialog.OnClickListener okClickListener =
+        (dialog, which) -> callback.onTracksSelected(selectionView.getSelectionParameters());
    AlertDialog dialog =
        builder
@@ -113,6 +153,8 @@ public class TrackSelectionView extends LinearLayout {
    inflater = LayoutInflater.from(context);
    componentListener = new ComponentListener();
    trackNameProvider = new DefaultTrackNameProvider(getResources());
+    parameters = DefaultTrackSelector.Parameters.DEFAULT;
+    trackGroups = TrackGroupArray.EMPTY;
    // View for disabling the renderer.
    disableView =
@@ -176,18 +218,35 @@ public class TrackSelectionView extends LinearLayout {
  }
  /**
-   * Initialize the view to select tracks for a specified renderer using a {@link
+   * Initialize the view to select tracks for a specified renderer using {@link MappedTrackInfo} and
-   * DefaultTrackSelector}.
+   * a set of {@link DefaultTrackSelector.Parameters}.
   *
-   * @param trackSelector The {@link DefaultTrackSelector}.
+   * @param mappedTrackInfo The {@link MappedTrackInfo}.
   * @param rendererIndex The index of the renderer.
+   * @param parameters The {@link DefaultTrackSelector.Parameters}.
   */
-  public void init(DefaultTrackSelector trackSelector, int rendererIndex) {
+  public void init(
-    this.trackSelector = trackSelector;
+      MappedTrackInfo mappedTrackInfo,
+      int rendererIndex,
+      DefaultTrackSelector.Parameters parameters) {
+    this.mappedTrackInfo = mappedTrackInfo;
    this.rendererIndex = rendererIndex;
+    this.parameters = parameters;
    updateViews();
  }
+  /** Returns the {@link DefaultTrackSelector.Parameters} for the current selection. */
+  public DefaultTrackSelector.Parameters getSelectionParameters() {
+    DefaultTrackSelector.ParametersBuilder parametersBuilder = parameters.buildUpon();
+    parametersBuilder.setRendererDisabled(rendererIndex, isDisabled);
+    if (override != null) {
+      parametersBuilder.setSelectionOverride(rendererIndex, trackGroups, override);
+    } else {
+      parametersBuilder.clearSelectionOverrides(rendererIndex);
+    }
+    return parametersBuilder.build();
+  }
  // Private methods.
  private void updateViews() {
@@ -196,9 +255,7 @@ public class TrackSelectionView extends LinearLayout {
      removeViewAt(i);
    }
-    MappingTrackSelector.MappedTrackInfo trackInfo =
+    if (mappedTrackInfo == null) {
-        trackSelector == null ? null : trackSelector.getCurrentMappedTrackInfo();
-    if (trackSelector == null || trackInfo == null) {
      // The view is not initialized.
      disableView.setEnabled(false);
      defaultView.setEnabled(false);
@@ -207,9 +264,8 @@ public class TrackSelectionView extends LinearLayout {
    disableView.setEnabled(true);
    defaultView.setEnabled(true);
-    trackGroups = trackInfo.getTrackGroups(rendererIndex);
+    trackGroups = mappedTrackInfo.getTrackGroups(rendererIndex);
-    DefaultTrackSelector.Parameters parameters = trackSelector.getParameters();
    isDisabled = parameters.getRendererDisabled(rendererIndex);
    override = parameters.getSelectionOverride(rendererIndex, trackGroups);
@@ -220,7 +276,7 @@ public class TrackSelectionView extends LinearLayout {
      boolean enableAdaptiveSelections =
          allowAdaptiveSelections
              && trackGroups.get(groupIndex).length > 1
-              && trackInfo.getAdaptiveSupport(rendererIndex, groupIndex, false)
+              && mappedTrackInfo.getAdaptiveSupport(rendererIndex, groupIndex, false)
                  != RendererCapabilities.ADAPTIVE_NOT_SUPPORTED;
      trackViews[groupIndex] = new CheckedTextView[group.length];
      for (int trackIndex = 0; trackIndex < group.length; trackIndex++) {
@@ -235,7 +291,7 @@ public class TrackSelectionView extends LinearLayout {
            (CheckedTextView) inflater.inflate(trackViewLayoutId, this, false);
        trackView.setBackgroundResource(selectableItemBackgroundResourceId);
        trackView.setText(trackNameProvider.getTrackName(group.getFormat(trackIndex)));
-        if (trackInfo.getTrackSupport(rendererIndex, groupIndex, trackIndex)
+        if (mappedTrackInfo.getTrackSupport(rendererIndex, groupIndex, trackIndex)
            == RendererCapabilities.FORMAT_HANDLED) {
          trackView.setFocusable(true);
          trackView.setTag(Pair.create(groupIndex, trackIndex));
@@ -263,17 +319,6 @@ public class TrackSelectionView extends LinearLayout {
    }
  }
-  private void applySelection() {
-    DefaultTrackSelector.ParametersBuilder parametersBuilder = trackSelector.buildUponParameters();
-    parametersBuilder.setRendererDisabled(rendererIndex, isDisabled);
-    if (override != null) {
-      parametersBuilder.setSelectionOverride(rendererIndex, trackGroups, override);
-    } else {
-      parametersBuilder.clearSelectionOverrides(rendererIndex);
-    }
-    trackSelector.setParameters(parametersBuilder);
-  }
  private void onClick(View view) {
    if (view == disableView) {
      onDisableViewClicked();

--- a/testutils_robolectric/src/main/java/com/google/android/exoplayer2/testutil/FakeTrackSelector.java
+++ b/testutils_robolectric/src/main/java/com/google/android/exoplayer2/testutil/FakeTrackSelector.java
@@ -79,8 +79,19 @@ public class FakeTrackSelector extends DefaultTrackSelector {
    }
    @Override
-    public TrackSelection createTrackSelection(
+    public TrackSelection[] createTrackSelections(
-        TrackGroup trackGroup, BandwidthMeter bandwidthMeter, int... tracks) {
+        TrackSelection.Definition[] definitions, BandwidthMeter bandwidthMeter) {
+      TrackSelection[] selections = new TrackSelection[definitions.length];
+      for (int i = 0; i < definitions.length; i++) {
+        TrackSelection.Definition definition = definitions[i];
+        if (definition != null) {
+          selections[i] = createTrackSelection(definition.group);
+        }
+      }
+      return selections;
+    }
+    private TrackSelection createTrackSelection(TrackGroup trackGroup) {
      if (mayReuseTrackSelection) {
        for (FakeTrackSelection trackSelection : trackSelections) {
          if (trackSelection.getTrackGroup().equals(trackGroup)) {
@@ -92,18 +103,5 @@ public class FakeTrackSelector extends DefaultTrackSelector {
      trackSelections.add(trackSelection);
      return trackSelection;
    }
-    @Override
-    public TrackSelection[] createTrackSelections(
-        TrackSelection.Definition[] definitions, BandwidthMeter bandwidthMeter) {
-      TrackSelection[] selections = new TrackSelection[definitions.length];
-      for (int i = 0; i < definitions.length; i++) {
-        TrackSelection.Definition definition = definitions[i];
-        if (definition != null) {
-          selections[i] = createTrackSelection(definition.group, bandwidthMeter, definition.tracks);
-        }
-      }
-      return selections;
-    }
  }
 }
--- a/testutils_robolectric/src/main/java/com/google/android/exoplayer2/testutil/TestDownloadManagerListener.java
+++ b/testutils_robolectric/src/main/java/com/google/android/exoplayer2/testutil/TestDownloadManagerListener.java
@@ -17,8 +17,8 @@ package com.google.android.exoplayer2.testutil;
 import static com.google.common.truth.Truth.assertThat;
-import com.google.android.exoplayer2.offline.DownloadAction;
 import com.google.android.exoplayer2.offline.DownloadManager;
+import com.google.android.exoplayer2.offline.DownloadManager.DownloadState;
 import java.util.HashMap;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.CountDownLatch;
@@ -31,10 +31,10 @@ public final class TestDownloadManagerListener implements DownloadManager.Listen
  private final DownloadManager downloadManager;
  private final DummyMainThread dummyMainThread;
-  private final HashMap<DownloadAction, ArrayBlockingQueue<Integer>> actionStates;
+  private final HashMap<String, ArrayBlockingQueue<Integer>> actionStates;
  private CountDownLatch downloadFinishedCondition;
-  private Throwable downloadError;
+  @DownloadState.FailureReason private int failureReason;
  public TestDownloadManagerListener(
      DownloadManager downloadManager, DummyMainThread dummyMainThread) {
@@ -43,12 +43,12 @@ public final class TestDownloadManagerListener implements DownloadManager.Listen
    actionStates = new HashMap<>();
  }
-  public int pollStateChange(DownloadAction action, long timeoutMs) throws InterruptedException {
+  public Integer pollStateChange(String taskId, long timeoutMs) throws InterruptedException {
-    return getStateQueue(action).poll(timeoutMs, TimeUnit.MILLISECONDS);
+    return getStateQueue(taskId).poll(timeoutMs, TimeUnit.MILLISECONDS);
  }
  public void clearDownloadError() {
-    this.downloadError = null;
+    this.failureReason = DownloadState.FAILURE_REASON_NONE;
  }
  @Override
@@ -57,12 +57,11 @@ public final class TestDownloadManagerListener implements DownloadManager.Listen
  }
  @Override
-  public void onTaskStateChanged(
+  public void onDownloadStateChanged(DownloadManager downloadManager, DownloadState downloadState) {
-      DownloadManager downloadManager, DownloadManager.TaskState taskState) {
+    if (downloadState.state == DownloadState.STATE_FAILED) {
-    if (taskState.state == DownloadManager.TaskState.STATE_FAILED && downloadError == null) {
+      failureReason = downloadState.failureReason;
-      downloadError = taskState.error;
    }
-    getStateQueue(taskState.action).add(taskState.state);
+    getStateQueue(downloadState.id).add(downloadState.state);
  }
  @Override
@@ -77,6 +76,14 @@ public final class TestDownloadManagerListener implements DownloadManager.Listen
   * error.
   */
  public void blockUntilTasksCompleteAndThrowAnyDownloadError() throws Throwable {
+    blockUntilTasksComplete();
+    if (failureReason != DownloadState.FAILURE_REASON_NONE) {
+      throw new Exception("Failure reason: " + DownloadState.getFailureString(failureReason));
+    }
+  }
+  /** Blocks until all remove and download tasks are complete. Task errors are ignored. */
+  public void blockUntilTasksComplete() throws InterruptedException {
    synchronized (this) {
      downloadFinishedCondition = new CountDownLatch(1);
    }
@@ -87,17 +94,14 @@ public final class TestDownloadManagerListener implements DownloadManager.Listen
          }
        });
    assertThat(downloadFinishedCondition.await(TIMEOUT, TimeUnit.MILLISECONDS)).isTrue();
-    if (downloadError != null) {
-      throw new Exception(downloadError);
-    }
  }
-  private ArrayBlockingQueue<Integer> getStateQueue(DownloadAction action) {
+  private ArrayBlockingQueue<Integer> getStateQueue(String taskId) {
    synchronized (actionStates) {
-      if (!actionStates.containsKey(action)) {
+      if (!actionStates.containsKey(taskId)) {
-        actionStates.put(action, new ArrayBlockingQueue<>(10));
+        actionStates.put(taskId, new ArrayBlockingQueue<>(10));
      }
-      return actionStates.get(action);
+      return actionStates.get(taskId);
    }
  }
 }