diff --git a/library/src/main/java/com/google/android/exoplayer2/ExoPlayerImpl.java b/library/src/main/java/com/google/android/exoplayer2/ExoPlayerImpl.java
index 0461465672..b167597e16 100644
--- a/library/src/main/java/com/google/android/exoplayer2/ExoPlayerImpl.java
+++ b/library/src/main/java/com/google/android/exoplayer2/ExoPlayerImpl.java
@@ -53,7 +53,6 @@ import java.util.concurrent.CopyOnWriteArraySet;
   // Playback information when there is a pending seek/set source operation.
   private int maskingPeriodIndex;
   private long maskingPositionMs;
-  private long maskingDurationMs;
 
   /**
    * Constructs an instance. Must be called from a thread that has an associated {@link Looper}.
@@ -142,11 +141,9 @@ import java.util.concurrent.CopyOnWriteArraySet;
 
   @Override
   public void seekTo(int periodIndex, long positionMs) {
-    boolean periodChanging = periodIndex != getCurrentPeriodIndex();
     boolean seekToDefaultPosition = positionMs == ExoPlayer.UNKNOWN_TIME;
     maskingPeriodIndex = periodIndex;
     maskingPositionMs = seekToDefaultPosition ? 0 : positionMs;
-    maskingDurationMs = periodChanging ? ExoPlayer.UNKNOWN_TIME : getDuration();
     pendingSeekAcks++;
     internalPlayer.seekTo(periodIndex, seekToDefaultPosition ? C.UNSET_TIME_US : positionMs * 1000);
     if (!seekToDefaultPosition) {
@@ -184,12 +181,10 @@ import java.util.concurrent.CopyOnWriteArraySet;
 
   @Override
   public long getDuration() {
-    if (pendingSeekAcks == 0) {
-      long durationUs = playbackInfo.durationUs;
-      return durationUs == C.UNSET_TIME_US ? ExoPlayer.UNKNOWN_TIME : durationUs / 1000;
-    } else {
-      return maskingDurationMs;
+    if (timeline == null) {
+      return UNKNOWN_TIME;
     }
+    return timeline.getPeriodDurationMs(getCurrentPeriodIndex());
   }
 
   @Override
diff --git a/library/src/main/java/com/google/android/exoplayer2/ExoPlayerImplInternal.java b/library/src/main/java/com/google/android/exoplayer2/ExoPlayerImplInternal.java
index 5c76bc63a6..5a410b78ed 100644
--- a/library/src/main/java/com/google/android/exoplayer2/ExoPlayerImplInternal.java
+++ b/library/src/main/java/com/google/android/exoplayer2/ExoPlayerImplInternal.java
@@ -54,12 +54,10 @@ import java.io.IOException;
 
     public volatile long positionUs;
     public volatile long bufferedPositionUs;
-    public volatile long durationUs;
     public volatile long startPositionUs;
 
     public PlaybackInfo(int periodIndex) {
       this.periodIndex = periodIndex;
-      durationUs = C.UNSET_TIME_US;
     }
 
   }
@@ -394,11 +392,6 @@ import java.io.IOException;
     }
     MediaPeriod mediaPeriod = playingPeriod.mediaPeriod;
 
-    // Update the duration.
-    if (playbackInfo.durationUs == C.UNSET_TIME_US) {
-      playbackInfo.durationUs = mediaPeriod.getDurationUs();
-    }
-
     // Update the playback position.
     long positionUs = mediaPeriod.readDiscontinuity();
     if (positionUs != C.UNSET_TIME_US) {
@@ -460,9 +453,10 @@ import java.io.IOException;
       maybeThrowPeriodPrepareError();
     }
 
+    long playingPeriodDuration = timeline.getPeriodDurationUs(playingPeriod.index);
     if (allRenderersEnded
-        && (playbackInfo.durationUs == C.UNSET_TIME_US
-            || playbackInfo.durationUs <= playbackInfo.positionUs)
+        && (playingPeriodDuration == C.UNSET_TIME_US
+            || playingPeriodDuration <= playbackInfo.positionUs)
         && isTimelineEnded) {
       setState(ExoPlayer.STATE_ENDED);
       stopRenderers();
@@ -796,7 +790,7 @@ import java.io.IOException;
       if (loadingPeriod.isLast) {
         return true;
       }
-      bufferedPositionUs = loadingPeriod.mediaPeriod.getDurationUs();
+      bufferedPositionUs = timeline.getPeriodDurationUs(loadingPeriod.index);
     }
     return loadControl.shouldStartPlayback(bufferedPositionUs - positionUs, rebuffering);
   }
@@ -945,6 +939,8 @@ import java.io.IOException;
         newPeriod.isLast = timeline.isFinal() && periodIndex == timeline.getPeriodCount() - 1;
         if (loadingPeriod != null) {
           loadingPeriod.setNextPeriod(newPeriod);
+          newPeriod.offsetUs = loadingPeriod.offsetUs
+              + timeline.getPeriodDurationUs(loadingPeriod.index);
         }
         bufferAheadPeriodCount++;
         loadingPeriod = newPeriod;
@@ -967,7 +963,7 @@ import java.io.IOException;
     // Update the playing and reading periods.
     if (playingPeriodEndPositionUs == C.UNSET_TIME_US && playingPeriod.isFullyBuffered()) {
       playingPeriodEndPositionUs = playingPeriod.offsetUs
-          + playingPeriod.mediaPeriod.getDurationUs();
+          + timeline.getPeriodDurationUs(playingPeriod.index);
     }
     while (playingPeriod != readingPeriod && playingPeriod.nextPeriod != null
         && internalPositionUs >= playingPeriod.nextPeriod.offsetUs) {
@@ -1198,7 +1194,6 @@ import java.io.IOException;
 
     public void setNextPeriod(Period nextPeriod) {
       this.nextPeriod = nextPeriod;
-      nextPeriod.offsetUs = offsetUs + mediaPeriod.getDurationUs();
     }
 
     public boolean isFullyBuffered() {
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/ConcatenatingMediaSource.java b/library/src/main/java/com/google/android/exoplayer2/source/ConcatenatingMediaSource.java
index f97b99b798..6987b18d70 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/ConcatenatingMediaSource.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/ConcatenatingMediaSource.java
@@ -148,10 +148,17 @@ public final class ConcatenatingMediaSource implements MediaSource {
     }
 
     @Override
-    public long getPeriodDuration(int index) {
+    public long getPeriodDurationMs(int index) {
       int sourceIndex = getSourceIndexForPeriod(index);
       int firstPeriodIndexInSource = getFirstPeriodIndexInSource(sourceIndex);
-      return timelines[sourceIndex].getPeriodDuration(index - firstPeriodIndexInSource);
+      return timelines[sourceIndex].getPeriodDurationMs(index - firstPeriodIndexInSource);
+    }
+
+    @Override
+    public long getPeriodDurationUs(int index) {
+      int sourceIndex = getSourceIndexForPeriod(index);
+      int firstPeriodIndexInSource = getFirstPeriodIndexInSource(sourceIndex);
+      return timelines[sourceIndex].getPeriodDurationUs(index - firstPeriodIndexInSource);
     }
 
     @Override
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/ExtractorMediaSource.java b/library/src/main/java/com/google/android/exoplayer2/source/ExtractorMediaSource.java
index df9a6c9ce8..846bf8aea1 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/ExtractorMediaSource.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/ExtractorMediaSource.java
@@ -228,11 +228,6 @@ public final class ExtractorMediaSource implements MediaPeriod, MediaSource,
     maybeThrowError();
   }
 
-  @Override
-  public long getDurationUs() {
-    return durationUs;
-  }
-
   @Override
   public TrackGroupArray getTrackGroups() {
     return tracks;
@@ -432,6 +427,9 @@ public final class ExtractorMediaSource implements MediaPeriod, MediaSource,
       long largestQueuedTimestampUs = getLargestQueuedTimestampUs();
       durationUs = largestQueuedTimestampUs == Long.MIN_VALUE ? 0
           : largestQueuedTimestampUs + DEFAULT_LAST_SAMPLE_DURATION_US;
+      sourceListener.onSourceInfoRefreshed(seekMap.isSeekable()
+          ? SinglePeriodTimeline.createSeekableFinalTimeline(this, durationUs)
+          : SinglePeriodTimeline.createUnseekableFinalTimeline(this, durationUs), null);
     }
   }
 
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/MediaPeriod.java b/library/src/main/java/com/google/android/exoplayer2/source/MediaPeriod.java
index 422725bc8f..323d5d8864 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/MediaPeriod.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/MediaPeriod.java
@@ -66,19 +66,6 @@ public interface MediaPeriod extends SequenceableLoader {
    */
   void maybeThrowPrepareError() throws IOException;
 
-  /**
-   * Returns the duration of the period in microseconds, or {@link C#UNSET_TIME_US} if not known.
-   * <p>
-   * If {@link #getBufferedPositionUs()} returns {@link C#END_OF_SOURCE_US}, the duration is
-   * guaranteed to be known.
-   * <p>
-   * This method should only be called after the period has been prepared.
-   *
-   * @return The duration of the period in microseconds, or {@link C#UNSET_TIME_US} if the duration
-   *     is not known.
-   */
-  long getDurationUs();
-
   /**
    * Returns the {@link TrackGroup}s exposed by the period.
    * <p>
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/MergingMediaPeriod.java b/library/src/main/java/com/google/android/exoplayer2/source/MergingMediaPeriod.java
index 5ba321dd54..82029dd940 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/MergingMediaPeriod.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/MergingMediaPeriod.java
@@ -32,7 +32,6 @@ public final class MergingMediaPeriod implements MediaPeriod, MediaPeriod.Callba
 
   private Callback callback;
   private int pendingChildPrepareCount;
-  private long durationUs;
   private TrackGroupArray trackGroups;
 
   private MediaPeriod[] enabledPeriods;
@@ -59,11 +58,6 @@ public final class MergingMediaPeriod implements MediaPeriod, MediaPeriod.Callba
     }
   }
 
-  @Override
-  public long getDurationUs() {
-    return durationUs;
-  }
-
   @Override
   public TrackGroupArray getTrackGroups() {
     return trackGroups;
@@ -194,15 +188,9 @@ public final class MergingMediaPeriod implements MediaPeriod, MediaPeriod.Callba
     if (--pendingChildPrepareCount > 0) {
       return;
     }
-    durationUs = 0;
     int totalTrackGroupCount = 0;
     for (MediaPeriod period : periods) {
       totalTrackGroupCount += period.getTrackGroups().length;
-      if (durationUs != C.UNSET_TIME_US) {
-        long periodDurationUs = period.getDurationUs();
-        durationUs = periodDurationUs == C.UNSET_TIME_US
-            ? C.UNSET_TIME_US : Math.max(durationUs, periodDurationUs);
-      }
     }
     TrackGroup[] trackGroupArray = new TrackGroup[totalTrackGroupCount];
     int trackGroupIndex = 0;
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/SinglePeriodTimeline.java b/library/src/main/java/com/google/android/exoplayer2/source/SinglePeriodTimeline.java
index fa36d27b59..3e08c6ffa9 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/SinglePeriodTimeline.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/SinglePeriodTimeline.java
@@ -16,6 +16,7 @@
 package com.google.android.exoplayer2.source;
 
 import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.util.Assertions;
 
 /**
@@ -52,7 +53,7 @@ public final class SinglePeriodTimeline implements Timeline {
    * @return A new, unseekable, final timeline with one period.
    */
   public static Timeline createUnseekableFinalTimeline(Object id, long durationUs) {
-    return new SinglePeriodTimeline(id, true, durationUs / 1000, SeekWindow.UNSEEKABLE);
+    return new SinglePeriodTimeline(id, true, durationUs, SeekWindow.UNSEEKABLE);
   }
 
   /**
@@ -64,19 +65,19 @@ public final class SinglePeriodTimeline implements Timeline {
    * @return A new, seekable, final timeline with one period.
    */
   public static Timeline createSeekableFinalTimeline(Object id, long durationUs) {
-    return new SinglePeriodTimeline(id, true, durationUs / 1000,
+    return new SinglePeriodTimeline(id, true, durationUs,
         SeekWindow.createWindowFromZero(durationUs));
   }
 
   private final Object id;
   private final boolean isFinal;
-  private final long durationMs;
+  private final long durationUs;
   private final SeekWindow seekWindow;
 
-  private SinglePeriodTimeline(Object id, boolean isFinal, long durationMs, SeekWindow seekWindow) {
+  private SinglePeriodTimeline(Object id, boolean isFinal, long durationUs, SeekWindow seekWindow) {
     this.id = Assertions.checkNotNull(id);
     this.isFinal = isFinal;
-    this.durationMs = durationMs;
+    this.durationUs = durationUs;
     this.seekWindow = seekWindow;
   }
 
@@ -96,11 +97,19 @@ public final class SinglePeriodTimeline implements Timeline {
   }
 
   @Override
-  public long getPeriodDuration(int index) {
+  public long getPeriodDurationMs(int index) {
     if (index != 0) {
       throw new IndexOutOfBoundsException();
     }
-    return durationMs;
+    return durationUs == C.UNSET_TIME_US ? ExoPlayer.UNKNOWN_TIME : (durationUs / 1000);
+  }
+
+  @Override
+  public long getPeriodDurationUs(int index) {
+    if (index != 0) {
+      throw new IndexOutOfBoundsException();
+    }
+    return durationUs;
   }
 
   @Override
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/SingleSampleMediaSource.java b/library/src/main/java/com/google/android/exoplayer2/source/SingleSampleMediaSource.java
index 1f1d0c51db..099ceb9481 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/SingleSampleMediaSource.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/SingleSampleMediaSource.java
@@ -147,11 +147,6 @@ public final class SingleSampleMediaSource implements MediaPeriod, MediaSource,
     // Do nothing.
   }
 
-  @Override
-  public long getDurationUs() {
-    return durationUs;
-  }
-
   @Override
   public TrackGroupArray getTrackGroups() {
     return tracks;
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/Timeline.java b/library/src/main/java/com/google/android/exoplayer2/source/Timeline.java
index 0b344d38d5..940e671e51 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/Timeline.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/Timeline.java
@@ -15,6 +15,7 @@
  */
 package com.google.android.exoplayer2.source;
 
+import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.ExoPlayer;
 
 /**
@@ -50,7 +51,16 @@ public interface Timeline {
    * @param index The index of the period.
    * @return The duration of the period in milliseconds, or {@link ExoPlayer#UNKNOWN_TIME}.
    */
-  long getPeriodDuration(int index);
+  long getPeriodDurationMs(int index);
+
+  /**
+   * Returns the duration of the period at {@code index} in the timeline, in microseconds, or
+   * {@link C#UNSET_TIME_US} if not known.
+   *
+   * @param index The index of the period.
+   * @return The duration of the period in microseconds, or {@link C#UNSET_TIME_US}.
+   */
+  long getPeriodDurationUs(int index);
 
   /**
    * Returns a unique identifier for the period at {@code index}, or {@code null} if the period at
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaPeriod.java b/library/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaPeriod.java
index 8eee46afbf..03575037eb 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaPeriod.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaPeriod.java
@@ -54,7 +54,6 @@ import java.util.List;
   private Callback callback;
   private Allocator allocator;
   private DashManifest manifest;
-  private long durationUs;
   private int index;
   private Period period;
 
@@ -69,7 +68,6 @@ import java.util.List;
     this.eventDispatcher = eventDispatcher;
     this.elapsedRealtimeOffset = elapsedRealtimeOffset;
     this.manifestLoaderErrorThrower = manifestLoaderErrorThrower;
-    durationUs = manifest.getPeriodDurationUs(index);
     period = manifest.getPeriod(index);
     trackGroups = buildTrackGroups(period);
   }
@@ -77,7 +75,6 @@ import java.util.List;
   public void updateManifest(DashManifest manifest, int index) {
     this.manifest = manifest;
     this.index = index;
-    durationUs = manifest.getPeriodDurationUs(index);
     period = manifest.getPeriod(index);
     if (sampleStreams != null) {
       for (ChunkSampleStream<DashChunkSource> sampleStream : sampleStreams) {
@@ -107,11 +104,6 @@ import java.util.List;
     manifestLoaderErrorThrower.maybeThrowError();
   }
 
-  @Override
-  public long getDurationUs() {
-    return durationUs;
-  }
-
   @Override
   public TrackGroupArray getTrackGroups() {
     return trackGroups;
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaSource.java b/library/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaSource.java
index ec958994ed..74b6b73f5e 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaSource.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaSource.java
@@ -509,13 +509,21 @@ public final class DashMediaSource implements MediaSource {
     }
 
     @Override
-    public long getPeriodDuration(int index) {
+    public long getPeriodDurationMs(int index) {
       if (index < 0 || index >= manifest.getPeriodCount()) {
         throw new IndexOutOfBoundsException();
       }
       return manifest.getPeriodDurationMs(index);
     }
 
+    @Override
+    public long getPeriodDurationUs(int index) {
+      if (index < 0 || index >= manifest.getPeriodCount()) {
+        throw new IndexOutOfBoundsException();
+      }
+      return manifest.getPeriodDurationUs(index);
+    }
+
     @Override
     public Object getPeriodId(int index) {
       if (index < 0 || index >= manifest.getPeriodCount()) {
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaSource.java b/library/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaSource.java
index 1a84a42642..fd9aebdc1d 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaSource.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/hls/HlsMediaSource.java
@@ -160,11 +160,6 @@ public final class HlsMediaSource implements MediaPeriod, MediaSource,
     }
   }
 
-  @Override
-  public long getDurationUs() {
-    return durationUs;
-  }
-
   @Override
   public TrackGroupArray getTrackGroups() {
     return trackGroups;
diff --git a/library/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaPeriod.java b/library/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaPeriod.java
index 018eb46dec..297fbe1151 100644
--- a/library/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaPeriod.java
+++ b/library/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaPeriod.java
@@ -98,11 +98,6 @@ import java.util.ArrayList;
     manifestLoaderErrorThrower.maybeThrowError();
   }
 
-  @Override
-  public long getDurationUs() {
-    return manifest.durationUs;
-  }
-
   @Override
   public TrackGroupArray getTrackGroups() {
     return trackGroups;