diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/AdtsExtractor.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/AdtsExtractor.java
index a22e17ce85..5915ea6885 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/AdtsExtractor.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/AdtsExtractor.java
@@ -15,7 +15,6 @@
  */
 package com.google.android.exoplayer.hls.parser;
 
-import com.google.android.exoplayer.MediaFormat;
 import com.google.android.exoplayer.upstream.DataSource;
 import com.google.android.exoplayer.util.ParsableByteArray;
 
@@ -43,23 +42,9 @@ public class AdtsExtractor implements HlsExtractor {
   }
 
   @Override
-  public void init(ExtractorOutput output) {
-    adtsReader = new AdtsReader(output.getTrackOutput(0));
-  }
-
-  @Override
-  public int getTrackCount() {
-    return 1;
-  }
-
-  @Override
-  public MediaFormat getFormat(int track) {
-    return adtsReader.getFormat();
-  }
-
-  @Override
-  public boolean isPrepared() {
-    return adtsReader != null && adtsReader.hasFormat();
+  public void init(TrackOutputBuilder output) {
+    adtsReader = new AdtsReader(output.buildOutput(0));
+    output.allOutputsBuilt();
   }
 
   @Override
diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/AdtsReader.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/AdtsReader.java
index 81c643c7a8..fc7417a60a 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/AdtsReader.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/AdtsReader.java
@@ -152,7 +152,7 @@ import java.util.Collections;
   private void parseHeader() {
     adtsScratch.setPosition(0);
 
-    if (!hasFormat()) {
+    if (!output.hasFormat()) {
       int audioObjectType = adtsScratch.readBits(2) + 1;
       int sampleRateIndex = adtsScratch.readBits(4);
       adtsScratch.skipBits(1);
@@ -167,7 +167,7 @@ import java.util.Collections;
           MediaFormat.NO_VALUE, audioParams.second, audioParams.first,
           Collections.singletonList(audioSpecificConfig));
       frameDurationUs = (C.MICROS_PER_SECOND * 1024L) / mediaFormat.sampleRate;
-      setFormat(mediaFormat);
+      output.setFormat(mediaFormat);
     } else {
       adtsScratch.skipBits(10);
     }
diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/ElementaryStreamReader.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/ElementaryStreamReader.java
index 8522cbeb18..a441ff35b9 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/ElementaryStreamReader.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/ElementaryStreamReader.java
@@ -15,7 +15,6 @@
  */
 package com.google.android.exoplayer.hls.parser;
 
-import com.google.android.exoplayer.MediaFormat;
 import com.google.android.exoplayer.hls.parser.HlsExtractor.TrackOutput;
 import com.google.android.exoplayer.util.ParsableByteArray;
 
@@ -25,7 +24,6 @@ import com.google.android.exoplayer.util.ParsableByteArray;
 /* package */ abstract class ElementaryStreamReader {
 
   protected final TrackOutput output;
-  private MediaFormat format;
 
   /**
    * @param output A {@link TrackOutput} to which samples should be written.
@@ -34,29 +32,6 @@ import com.google.android.exoplayer.util.ParsableByteArray;
     this.output = output;
   }
 
-  /**
-   * True if the format of the stream is known. False otherwise.
-   */
-  public boolean hasFormat() {
-    return format != null;
-  }
-
-  /**
-   * Returns the format of the stream, or {@code null} if {@link #hasFormat()} is false.
-   */
-  public MediaFormat getFormat() {
-    return format;
-  }
-
-  /**
-   * Sets the format of the stream.
-   *
-   * @param format The format.
-   */
-  protected void setFormat(MediaFormat format) {
-    this.format = format;
-  }
-
   /**
    * Consumes (possibly partial) payload data.
    *
diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/H264Reader.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/H264Reader.java
index ae9d0fe7a9..40b3b1ca32 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/H264Reader.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/H264Reader.java
@@ -88,7 +88,7 @@ import java.util.List;
           int nalUnitOffsetInData = nextNalUnitOffset - limit;
           if (nalUnitType == NAL_UNIT_TYPE_AUD) {
             if (output.isWritingSample()) {
-              if (isKeyframe && !hasFormat() && sps.isCompleted() && pps.isCompleted()) {
+              if (isKeyframe && !output.hasFormat() && sps.isCompleted() && pps.isCompleted()) {
                 parseMediaFormat(sps, pps);
               }
               output.commitSample(isKeyframe ? C.SAMPLE_FLAG_SYNC : 0, nalUnitOffsetInData, null);
@@ -120,7 +120,7 @@ import java.util.List;
   }
 
   private void feedNalUnitTargetBuffersStart(int nalUnitType) {
-    if (!hasFormat()) {
+    if (!output.hasFormat()) {
       sps.startNalUnit(nalUnitType);
       pps.startNalUnit(nalUnitType);
     }
@@ -128,7 +128,7 @@ import java.util.List;
   }
 
   private void feedNalUnitTargetBuffersData(byte[] dataArray, int offset, int limit) {
-    if (!hasFormat()) {
+    if (!output.hasFormat()) {
       sps.appendToNalUnit(dataArray, offset, limit);
       pps.appendToNalUnit(dataArray, offset, limit);
     }
@@ -233,7 +233,7 @@ import java.util.List;
     }
 
     // Set the format.
-    setFormat(MediaFormat.createVideoFormat(MimeTypes.VIDEO_H264, MediaFormat.NO_VALUE,
+    output.setFormat(MediaFormat.createVideoFormat(MimeTypes.VIDEO_H264, MediaFormat.NO_VALUE,
         frameWidth, frameHeight, initializationData));
   }
 
diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/HlsExtractor.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/HlsExtractor.java
index 92a4ac6717..e3b3e5468f 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/HlsExtractor.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/HlsExtractor.java
@@ -29,15 +29,21 @@ public interface HlsExtractor {
   /**
    * An object to which extracted data should be output.
    */
-  public interface ExtractorOutput {
+  public interface TrackOutputBuilder {
 
     /**
-     * Obtains a {@link TrackOutput} to which extracted data should be output for a given track.
+     * Invoked to build a {@link TrackOutput} to which data should be output for a given track.
      *
      * @param trackId A stable track id.
      * @return The corresponding {@link TrackOutput}.
      */
-    TrackOutput getTrackOutput(int trackId);
+    TrackOutput buildOutput(int trackId);
+
+    /**
+     * Invoked when all {@link TrackOutput}s have been built, meaning {@link #buildOutput(int)}
+     * will not be invoked again.
+     */
+    void allOutputsBuilt();
 
   }
 
@@ -46,6 +52,12 @@ public interface HlsExtractor {
    */
   public interface TrackOutput {
 
+    boolean hasFormat();
+
+    void setFormat(MediaFormat format);
+
+    boolean isWritingSample();
+
     int appendData(DataSource dataSource, int length) throws IOException;
 
     void appendData(ParsableByteArray data, int length);
@@ -54,42 +66,14 @@ public interface HlsExtractor {
 
     void commitSample(int flags, int offset, byte[] encryptionKey);
 
-    boolean isWritingSample();
-
   }
 
   /**
    * Initializes the extractor.
    *
-   * @param output An {@link ExtractorOutput} to which extracted data should be output.
+   * @param output A {@link TrackOutputBuilder} to which extracted data should be output.
    */
-  void init(ExtractorOutput output);
-
-  /**
-   * Whether the extractor is prepared.
-   *
-   * @return True if the extractor is prepared. False otherwise.
-   */
-  boolean isPrepared();
-
-  /**
-   * Gets the number of available tracks.
-   * <p>
-   * This method should only be called after the extractor has been prepared.
-   *
-   * @return The number of available tracks.
-   */
-  int getTrackCount();
-
-  /**
-   * Gets the format of the specified track.
-   * <p>
-   * This method must only be called after the extractor has been prepared.
-   *
-   * @param track The track index.
-   * @return The corresponding format.
-   */
-  MediaFormat getFormat(int track);
+  void init(TrackOutputBuilder output);
 
   /**
    * Reads up to a single TS packet.
diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/HlsExtractorWrapper.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/HlsExtractorWrapper.java
index b44626722f..40bc8f7280 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/HlsExtractorWrapper.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/HlsExtractorWrapper.java
@@ -29,15 +29,17 @@ import java.io.IOException;
 /**
  * Wraps a {@link HlsExtractor}, adding functionality to enable reading of the extracted samples.
  */
-public final class HlsExtractorWrapper implements HlsExtractor.ExtractorOutput {
+public final class HlsExtractorWrapper implements HlsExtractor.TrackOutputBuilder {
 
   private final BufferPool bufferPool;
   private final HlsExtractor extractor;
+  private final SparseArray<SampleQueue> sampleQueues;
   private final boolean shouldSpliceIn;
 
-  private SparseArray<SampleQueue> sampleQueues;
+  private volatile boolean outputsBuilt;
 
   // Accessed only by the consuming thread.
+  private boolean prepared;
   private boolean spliceConfigured;
 
   public HlsExtractorWrapper(BufferPool bufferPool, HlsExtractor extractor,
@@ -88,7 +90,7 @@ public final class HlsExtractorWrapper implements HlsExtractor.ExtractorOutput {
    * @return The number of available tracks.
    */
   public int getTrackCount() {
-    return extractor.getTrackCount();
+    return sampleQueues.size();
   }
 
   /**
@@ -100,7 +102,7 @@ public final class HlsExtractorWrapper implements HlsExtractor.ExtractorOutput {
    * @return The corresponding format.
    */
   public MediaFormat getFormat(int track) {
-    return extractor.getFormat(track);
+    return sampleQueues.valueAt(track).getFormat();
   }
 
   /**
@@ -109,7 +111,15 @@ public final class HlsExtractorWrapper implements HlsExtractor.ExtractorOutput {
    * @return True if the extractor is prepared. False otherwise.
    */
   public boolean isPrepared() {
-    return extractor.isPrepared();
+    if (!prepared && outputsBuilt) {
+      for (int i = 0; i < sampleQueues.size(); i++) {
+        if (!sampleQueues.valueAt(i).hasFormat()) {
+          return false;
+        }
+      }
+      prepared = true;
+    }
+    return prepared;
   }
 
   /**
@@ -186,13 +196,15 @@ public final class HlsExtractorWrapper implements HlsExtractor.ExtractorOutput {
   // ExtractorOutput implementation.
 
   @Override
-  public TrackOutput getTrackOutput(int id) {
-    SampleQueue sampleQueue = sampleQueues.get(id);
-    if (sampleQueue == null) {
-      sampleQueue = new SampleQueue(bufferPool);
-      sampleQueues.put(id, sampleQueue);
-    }
+  public TrackOutput buildOutput(int id) {
+    SampleQueue sampleQueue = new SampleQueue(bufferPool);
+    sampleQueues.put(id, sampleQueue);
     return sampleQueue;
   }
 
+  @Override
+  public void allOutputsBuilt() {
+    this.outputsBuilt = true;
+  }
+
 }
diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/Id3Reader.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/Id3Reader.java
index a76bcdbaa4..d48aa6e56d 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/Id3Reader.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/Id3Reader.java
@@ -27,7 +27,7 @@ import com.google.android.exoplayer.util.ParsableByteArray;
 
   public Id3Reader(TrackOutput output) {
     super(output);
-    setFormat(MediaFormat.createId3Format());
+    output.setFormat(MediaFormat.createId3Format());
   }
 
   @Override
diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/SampleQueue.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/SampleQueue.java
index 5e9bd7950f..4f78f494bb 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/SampleQueue.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/SampleQueue.java
@@ -16,6 +16,7 @@
 package com.google.android.exoplayer.hls.parser;
 
 import com.google.android.exoplayer.C;
+import com.google.android.exoplayer.MediaFormat;
 import com.google.android.exoplayer.SampleHolder;
 import com.google.android.exoplayer.hls.parser.HlsExtractor.TrackOutput;
 import com.google.android.exoplayer.upstream.BufferPool;
@@ -44,6 +45,7 @@ public final class SampleQueue implements TrackOutput {
 
   // Accessed by both the loading and consuming threads.
   private volatile long largestParsedTimestampUs;
+  private volatile MediaFormat format;
 
   public SampleQueue(BufferPool bufferPool) {
     rollingBuffer = new RollingSampleBuffer(bufferPool);
@@ -60,6 +62,10 @@ public final class SampleQueue implements TrackOutput {
 
   // Called by the consuming thread.
 
+  public MediaFormat getFormat() {
+    return format;
+  }
+
   public long getLargestParsedTimestampUs() {
     return largestParsedTimestampUs;
   }
@@ -162,6 +168,16 @@ public final class SampleQueue implements TrackOutput {
 
   // TrackOutput implementation. Called by the loading thread.
 
+  @Override
+  public boolean hasFormat() {
+    return format != null;
+  }
+
+  @Override
+  public void setFormat(MediaFormat format) {
+    this.format = format;
+  }
+
   @Override
   public int appendData(DataSource dataSource, int length) throws IOException {
     return rollingBuffer.appendData(dataSource, length);
diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/SeiReader.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/SeiReader.java
index 2bf48be730..979bc44d5f 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/SeiReader.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/SeiReader.java
@@ -31,7 +31,7 @@ import com.google.android.exoplayer.util.ParsableByteArray;
 
   public SeiReader(TrackOutput output) {
     super(output);
-    setFormat(MediaFormat.createEia608Format());
+    output.setFormat(MediaFormat.createEia608Format());
   }
 
   @Override
diff --git a/library/src/main/java/com/google/android/exoplayer/hls/parser/TsExtractor.java b/library/src/main/java/com/google/android/exoplayer/hls/parser/TsExtractor.java
index 15eae10354..4a4417270a 100644
--- a/library/src/main/java/com/google/android/exoplayer/hls/parser/TsExtractor.java
+++ b/library/src/main/java/com/google/android/exoplayer/hls/parser/TsExtractor.java
@@ -16,9 +16,7 @@
 package com.google.android.exoplayer.hls.parser;
 
 import com.google.android.exoplayer.C;
-import com.google.android.exoplayer.MediaFormat;
 import com.google.android.exoplayer.upstream.DataSource;
-import com.google.android.exoplayer.util.Assertions;
 import com.google.android.exoplayer.util.ParsableBitArray;
 import com.google.android.exoplayer.util.ParsableByteArray;
 
@@ -52,14 +50,11 @@ public final class TsExtractor implements HlsExtractor {
   private final ParsableBitArray tsScratch;
 
   // Accessed only by the loading thread.
-  private ExtractorOutput output;
+  private TrackOutputBuilder output;
   private int tsPacketBytesRead;
   private long timestampOffsetUs;
   private long lastPts;
 
-  // Accessed by both the loading and consuming threads.
-  private volatile boolean prepared;
-
   public TsExtractor(long firstSampleTimestamp) {
     this.firstSampleTimestamp = firstSampleTimestamp;
     tsScratch = new ParsableBitArray(new byte[3]);
@@ -71,40 +66,10 @@ public final class TsExtractor implements HlsExtractor {
   }
 
   @Override
-  public void init(ExtractorOutput output) {
+  public void init(TrackOutputBuilder output) {
     this.output = output;
   }
 
-  @Override
-  public int getTrackCount() {
-    Assertions.checkState(prepared);
-    return streamReaders.size();
-  }
-
-  @Override
-  public MediaFormat getFormat(int track) {
-    Assertions.checkState(prepared);
-    return streamReaders.valueAt(track).getFormat();
-  }
-
-  @Override
-  public boolean isPrepared() {
-    return prepared;
-  }
-
-  private boolean checkPrepared() {
-    int pesPayloadReaderCount = streamReaders.size();
-    if (pesPayloadReaderCount == 0) {
-      return false;
-    }
-    for (int i = 0; i < pesPayloadReaderCount; i++) {
-      if (!streamReaders.valueAt(i).hasFormat()) {
-        return false;
-      }
-    }
-    return true;
-  }
-
   @Override
   public int read(DataSource dataSource) throws IOException {
     int bytesRead = dataSource.read(tsPacketBuffer.data, tsPacketBytesRead,
@@ -153,10 +118,6 @@ public final class TsExtractor implements HlsExtractor {
       }
     }
 
-    if (!prepared) {
-      prepared = checkPrepared();
-    }
-
     return bytesRead;
   }
 
@@ -193,7 +154,7 @@ public final class TsExtractor implements HlsExtractor {
   private abstract static class TsPayloadReader {
 
     public abstract void consume(ParsableByteArray data, boolean payloadUnitStartIndicator,
-        ExtractorOutput output);
+        TrackOutputBuilder output);
 
   }
 
@@ -210,7 +171,7 @@ public final class TsExtractor implements HlsExtractor {
 
     @Override
     public void consume(ParsableByteArray data, boolean payloadUnitStartIndicator,
-        ExtractorOutput output) {
+        TrackOutputBuilder output) {
       // Skip pointer.
       if (payloadUnitStartIndicator) {
         int pointerField = data.readUnsignedByte();
@@ -250,7 +211,7 @@ public final class TsExtractor implements HlsExtractor {
 
     @Override
     public void consume(ParsableByteArray data, boolean payloadUnitStartIndicator,
-        ExtractorOutput output) {
+        TrackOutputBuilder output) {
       // Skip pointer.
       if (payloadUnitStartIndicator) {
         int pointerField = data.readUnsignedByte();
@@ -294,16 +255,16 @@ public final class TsExtractor implements HlsExtractor {
         ElementaryStreamReader pesPayloadReader = null;
         switch (streamType) {
           case TS_STREAM_TYPE_AAC:
-            pesPayloadReader = new AdtsReader(output.getTrackOutput(TS_STREAM_TYPE_AAC));
+            pesPayloadReader = new AdtsReader(output.buildOutput(TS_STREAM_TYPE_AAC));
             break;
           case TS_STREAM_TYPE_H264:
-            SeiReader seiReader = new SeiReader(output.getTrackOutput(TS_STREAM_TYPE_EIA608));
+            SeiReader seiReader = new SeiReader(output.buildOutput(TS_STREAM_TYPE_EIA608));
             streamReaders.put(TS_STREAM_TYPE_EIA608, seiReader);
-            pesPayloadReader = new H264Reader(output.getTrackOutput(TS_STREAM_TYPE_H264),
+            pesPayloadReader = new H264Reader(output.buildOutput(TS_STREAM_TYPE_H264),
                 seiReader);
             break;
           case TS_STREAM_TYPE_ID3:
-            pesPayloadReader = new Id3Reader(output.getTrackOutput(TS_STREAM_TYPE_ID3));
+            pesPayloadReader = new Id3Reader(output.buildOutput(TS_STREAM_TYPE_ID3));
             break;
         }
 
@@ -313,7 +274,7 @@ public final class TsExtractor implements HlsExtractor {
         }
       }
 
-      // Skip CRC_32.
+      output.allOutputsBuilt();
     }
 
   }
@@ -353,7 +314,7 @@ public final class TsExtractor implements HlsExtractor {
 
     @Override
     public void consume(ParsableByteArray data, boolean payloadUnitStartIndicator,
-        ExtractorOutput output) {
+        TrackOutputBuilder output) {
       if (payloadUnitStartIndicator) {
         switch (state) {
           case STATE_FINDING_HEADER: