diff --git a/library/core/src/main/java/com/google/android/exoplayer2/extractor/mp4/FragmentedMp4Extractor.java b/library/core/src/main/java/com/google/android/exoplayer2/extractor/mp4/FragmentedMp4Extractor.java
index 28a1ffaa7b..9a70dfbf90 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/extractor/mp4/FragmentedMp4Extractor.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/extractor/mp4/FragmentedMp4Extractor.java
@@ -16,6 +16,7 @@
 package com.google.android.exoplayer2.extractor.mp4;
 
 import android.support.annotation.IntDef;
+import android.support.annotation.Nullable;
 import android.util.Log;
 import android.util.Pair;
 import android.util.SparseArray;
@@ -44,10 +45,10 @@ import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
+import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.LinkedList;
 import java.util.List;
 import java.util.Stack;
 import java.util.UUID;
@@ -108,6 +109,8 @@ public final class FragmentedMp4Extractor implements Extractor {
   private static final int SAMPLE_GROUP_TYPE_seig = Util.getIntegerCodeForString("seig");
   private static final byte[] PIFF_SAMPLE_ENCRYPTION_BOX_EXTENDED_TYPE =
       new byte[] {-94, 57, 79, 82, 90, -101, 79, 20, -94, 68, 108, 66, 124, 100, -115, -12};
+  private static final Format EMSG_FORMAT =
+      Format.createSampleFormat(null, MimeTypes.APPLICATION_EMSG, Format.OFFSET_SAMPLE_RELATIVE);
 
   // Parser states.
   private static final int STATE_READING_ATOM_HEADER = 0;
@@ -141,7 +144,8 @@ public final class FragmentedMp4Extractor implements Extractor {
   private final ParsableByteArray atomHeader;
   private final byte[] extendedTypeScratch;
   private final Stack<ContainerAtom> containerAtoms;
-  private final LinkedList<MetadataSampleInfo> pendingMetadataSampleInfos;
+  private final ArrayDeque<MetadataSampleInfo> pendingMetadataSampleInfos;
+  private final @Nullable TrackOutput additionalEmsgTrackOutput;
 
   private int parserState;
   private int atomType;
@@ -161,7 +165,7 @@ public final class FragmentedMp4Extractor implements Extractor {
 
   // Extractor output.
   private ExtractorOutput extractorOutput;
-  private TrackOutput eventMessageTrackOutput;
+  private TrackOutput[] emsgTrackOutputs;
   private TrackOutput[] cea608TrackOutputs;
 
   // Whether extractorOutput.seekMap has been called.
@@ -212,11 +216,32 @@ public final class FragmentedMp4Extractor implements Extractor {
    */
   public FragmentedMp4Extractor(@Flags int flags, TimestampAdjuster timestampAdjuster,
       Track sideloadedTrack, DrmInitData sideloadedDrmInitData, List<Format> closedCaptionFormats) {
+    this(flags, timestampAdjuster, sideloadedTrack, sideloadedDrmInitData,
+        closedCaptionFormats, null);
+  }
+
+  /**
+   * @param flags Flags that control the extractor's behavior.
+   * @param timestampAdjuster Adjusts sample timestamps. May be null if no adjustment is needed.
+   * @param sideloadedTrack Sideloaded track information, in the case that the extractor
+   *     will not receive a moov box in the input data. Null if a moov box is expected.
+   * @param sideloadedDrmInitData The {@link DrmInitData} to use for encrypted tracks. If null, the
+   *     pssh boxes (if present) will be used.
+   * @param closedCaptionFormats For tracks that contain SEI messages, the formats of the closed
+   *     caption channels to expose.
+   * @param additionalEmsgTrackOutput An extra track output that will receive all emsg messages
+   *     targeting the player, even if {@link #FLAG_ENABLE_EMSG_TRACK} is not set. Null if special
+   *     handling of emsg messages for players is not required.
+   */
+  public FragmentedMp4Extractor(@Flags int flags, TimestampAdjuster timestampAdjuster,
+      Track sideloadedTrack, DrmInitData sideloadedDrmInitData, List<Format> closedCaptionFormats,
+      @Nullable TrackOutput additionalEmsgTrackOutput) {
     this.flags = flags | (sideloadedTrack != null ? FLAG_SIDELOADED : 0);
     this.timestampAdjuster = timestampAdjuster;
     this.sideloadedTrack = sideloadedTrack;
     this.sideloadedDrmInitData = sideloadedDrmInitData;
     this.closedCaptionFormats = Collections.unmodifiableList(closedCaptionFormats);
+    this.additionalEmsgTrackOutput = additionalEmsgTrackOutput;
     atomHeader = new ParsableByteArray(Atom.LONG_HEADER_SIZE);
     nalStartCode = new ParsableByteArray(NalUnitUtil.NAL_START_CODE);
     nalPrefix = new ParsableByteArray(5);
@@ -225,7 +250,7 @@ public final class FragmentedMp4Extractor implements Extractor {
     defaultInitializationVector = new ParsableByteArray();
     extendedTypeScratch = new byte[16];
     containerAtoms = new Stack<>();
-    pendingMetadataSampleInfos = new LinkedList<>();
+    pendingMetadataSampleInfos = new ArrayDeque<>();
     trackBundles = new SparseArray<>();
     durationUs = C.TIME_UNSET;
     segmentIndexEarliestPresentationTimeUs = C.TIME_UNSET;
@@ -494,10 +519,21 @@ public final class FragmentedMp4Extractor implements Extractor {
   }
 
   private void maybeInitExtraTracks() {
-    if ((flags & FLAG_ENABLE_EMSG_TRACK) != 0 && eventMessageTrackOutput == null) {
-      eventMessageTrackOutput = extractorOutput.track(trackBundles.size(), C.TRACK_TYPE_METADATA);
-      eventMessageTrackOutput.format(Format.createSampleFormat(null, MimeTypes.APPLICATION_EMSG,
-          Format.OFFSET_SAMPLE_RELATIVE));
+    if (emsgTrackOutputs == null) {
+      emsgTrackOutputs = new TrackOutput[2];
+      int emsgTrackOutputCount = 0;
+      if (additionalEmsgTrackOutput != null) {
+        emsgTrackOutputs[emsgTrackOutputCount++] = additionalEmsgTrackOutput;
+      }
+      if ((flags & FLAG_ENABLE_EMSG_TRACK) != 0) {
+        emsgTrackOutputs[emsgTrackOutputCount++] =
+            extractorOutput.track(trackBundles.size(), C.TRACK_TYPE_METADATA);
+      }
+      emsgTrackOutputs = Arrays.copyOf(emsgTrackOutputs, emsgTrackOutputCount);
+
+      for (TrackOutput eventMessageTrackOutput : emsgTrackOutputs) {
+        eventMessageTrackOutput.format(EMSG_FORMAT);
+      }
     }
     if (cea608TrackOutputs == null) {
       cea608TrackOutputs = new TrackOutput[closedCaptionFormats.size()];
@@ -510,29 +546,34 @@ public final class FragmentedMp4Extractor implements Extractor {
   }
 
   /**
-   * Handles an emsg atom (defined in 23009-1).
+   * Parses an emsg atom (defined in 23009-1).
    */
   private void onEmsgLeafAtomRead(ParsableByteArray atom) {
-    if (eventMessageTrackOutput == null) {
+    if (emsgTrackOutputs.length == 0) {
       return;
     }
-    // Parse the event's presentation time delta.
+
     atom.setPosition(Atom.FULL_HEADER_SIZE);
+    int sampleSize = atom.bytesLeft();
     atom.readNullTerminatedString(); // schemeIdUri
     atom.readNullTerminatedString(); // value
     long timescale = atom.readUnsignedInt();
     long presentationTimeDeltaUs =
         Util.scaleLargeTimestamp(atom.readUnsignedInt(), C.MICROS_PER_SECOND, timescale);
+
     // Output the sample data.
-    atom.setPosition(Atom.FULL_HEADER_SIZE);
-    int sampleSize = atom.bytesLeft();
-    eventMessageTrackOutput.sampleData(atom, sampleSize);
+    for (TrackOutput emsgTrackOutput : emsgTrackOutputs) {
+      atom.setPosition(Atom.FULL_HEADER_SIZE);
+      emsgTrackOutput.sampleData(atom, sampleSize);
+    }
+
     // Output the sample metadata.
     if (segmentIndexEarliestPresentationTimeUs != C.TIME_UNSET) {
-      // We can output the sample metadata immediately.
-      eventMessageTrackOutput.sampleMetadata(
-          segmentIndexEarliestPresentationTimeUs + presentationTimeDeltaUs,
-          C.BUFFER_FLAG_KEY_FRAME, sampleSize, 0 /* offset */, null);
+      for (TrackOutput emsgTrackOutput : emsgTrackOutputs) {
+        emsgTrackOutput.sampleMetadata(
+            segmentIndexEarliestPresentationTimeUs + presentationTimeDeltaUs,
+            C.BUFFER_FLAG_KEY_FRAME, sampleSize, 0 /* offset */, null);
+      }
     } else {
       // We need the first sample timestamp in the segment before we can output the metadata.
       pendingMetadataSampleInfos.addLast(
@@ -1194,13 +1235,8 @@ public final class FragmentedMp4Extractor implements Extractor {
 
     output.sampleMetadata(sampleTimeUs, sampleFlags, sampleSize, 0, cryptoData);
 
-    while (!pendingMetadataSampleInfos.isEmpty()) {
-      MetadataSampleInfo sampleInfo = pendingMetadataSampleInfos.removeFirst();
-      pendingMetadataSampleBytes -= sampleInfo.size;
-      eventMessageTrackOutput.sampleMetadata(
-          sampleTimeUs + sampleInfo.presentationTimeDeltaUs,
-          C.BUFFER_FLAG_KEY_FRAME, sampleInfo.size, pendingMetadataSampleBytes, null);
-    }
+    // After we have the sampleTimeUs, we can commit all the pending metadata samples
+    outputPendingMetadataSamples(sampleTimeUs);
 
     currentTrackBundle.currentSampleIndex++;
     currentTrackBundle.currentSampleInTrackRun++;
@@ -1214,6 +1250,18 @@ public final class FragmentedMp4Extractor implements Extractor {
     return true;
   }
 
+  private void outputPendingMetadataSamples(long sampleTimeUs) {
+    while (!pendingMetadataSampleInfos.isEmpty()) {
+      MetadataSampleInfo sampleInfo = pendingMetadataSampleInfos.removeFirst();
+      pendingMetadataSampleBytes -= sampleInfo.size;
+      for (TrackOutput emsgTrackOutput : emsgTrackOutputs) {
+        emsgTrackOutput.sampleMetadata(
+            sampleTimeUs + sampleInfo.presentationTimeDeltaUs,
+            C.BUFFER_FLAG_KEY_FRAME, sampleInfo.size, pendingMetadataSampleBytes, null);
+      }
+    }
+  }
+
   /**
    * Returns the {@link TrackBundle} whose fragment run has the earliest file position out of those
    * yet to be consumed, or null if all have been consumed.