Allow late HLS sample queue building

Issue:#3149

-------------
Created by MOE: https:/google/moe
MOE_MIGRATED_REVID=177836048

ISSUE_TEMPLATE

@@ -1,3 +1,5 @@
+*** ISSUES THAT IGNORE THIS TEMPLATE WILL BE CLOSED WITHOUT INVESTIGATION ***
+
 Before filing an issue:
 -----------------------
 - Search existing issues, including issues that are closed.

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

@@ -15,6 +15,7 @@
  */
 package com.google.android.exoplayer2.source.hls;
 
+import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.FormatHolder;
 import com.google.android.exoplayer2.decoder.DecoderInputBuffer;
 import com.google.android.exoplayer2.source.SampleStream;
@@ -25,33 +26,60 @@
  */
 /* package */ final class HlsSampleStream implements SampleStream {
 
- public final int sampleQueueIndex;
-
+ private final int trackGroupIndex;
  private final HlsSampleStreamWrapper sampleStreamWrapper;
+ private int sampleQueueIndex;
 
- public HlsSampleStream(HlsSampleStreamWrapper sampleStreamWrapper, int sampleQueueIndex) {
+ public HlsSampleStream(HlsSampleStreamWrapper sampleStreamWrapper, int trackGroupIndex) {
  this.sampleStreamWrapper = sampleStreamWrapper;
- this.sampleQueueIndex = sampleQueueIndex;
+ this.trackGroupIndex = trackGroupIndex;
+ }
+
+ public void unbindSampleQueue() {
+ if (sampleQueueIndex != C.INDEX_UNSET) {
+ sampleStreamWrapper.unbindSampleQueue(trackGroupIndex);
+ }
  }
 
+ // SampleStream implementation.
+
  @Override
  public boolean isReady() {
- return sampleStreamWrapper.isReady(sampleQueueIndex);
+ return ensureBoundSampleQueue() && sampleStreamWrapper.isReady(sampleQueueIndex);
  }
 
  @Override
  public void maybeThrowError() throws IOException {
+ if (!ensureBoundSampleQueue()) {
+ throw new SampleQueueMappingException(
+ sampleStreamWrapper.getTrackGroups().get(trackGroupIndex).getFormat(0).sampleMimeType);
+ }
  sampleStreamWrapper.maybeThrowError();
  }
 
  @Override
  public int readData(FormatHolder formatHolder, DecoderInputBuffer buffer, boolean requireFormat) {
+ if (!ensureBoundSampleQueue()) {
+ return C.RESULT_NOTHING_READ;
+ }
  return sampleStreamWrapper.readData(sampleQueueIndex, formatHolder, buffer, requireFormat);
  }
 
  @Override
  public int skipData(long positionUs) {
+ if (!ensureBoundSampleQueue()) {
+ return 0;
+ }
  return sampleStreamWrapper.skipData(sampleQueueIndex, positionUs);
  }
 
+ // Internal methods.
+
+ private boolean ensureBoundSampleQueue() {
+ if (sampleQueueIndex != C.INDEX_UNSET) {
+ return true;
+ }
+ sampleQueueIndex = sampleStreamWrapper.bindSampleQueueToSampleStream(trackGroupIndex);
+ return sampleQueueIndex != C.INDEX_UNSET;
+ }
 }

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

@@ -88,13 +88,14 @@ public interface Callback extends SequenceableLoader.Callback<HlsSampleStreamWra
  private final HlsChunkSource.HlsChunkHolder nextChunkHolder;
  private final ArrayList<HlsMediaChunk> mediaChunks;
  private final Runnable maybeFinishPrepareRunnable;
+ private final Runnable onTracksEndedRunnable;
  private final Handler handler;
 
  private SampleQueue[] sampleQueues;
  private int[] sampleQueueTrackIds;
  private boolean sampleQueuesBuilt;
  private boolean prepared;
- private int enabledSampleQueueCount;
+ private int enabledTrackGroupCount;
  private Format downstreamTrackFormat;
  private boolean released;
 
@@ -108,13 +109,16 @@ public interface Callback extends SequenceableLoader.Callback<HlsSampleStreamWra
  private boolean[] sampleQueuesEnabledStates;
  private boolean[] sampleQueueIsAudioVideoFlags;
 
- private long sampleOffsetUs;
  private long lastSeekPositionUs;
  private long pendingResetPositionUs;
  private boolean pendingResetUpstreamFormats;
  private boolean seenFirstTrackSelection;
  private boolean loadingFinished;
 
+ // Accessed only by the loading thread.
+ private boolean tracksEnded;
+ private long sampleOffsetUs;
+
  /**
  * @param trackType The type of the track. One of the {@link C} {@code TRACK_TYPE_*} constants.
  * @param callback A callback for the wrapper.
@@ -143,12 +147,20 @@ public HlsSampleStreamWrapper(int trackType, Callback callback, HlsChunkSource c
  sampleQueueIsAudioVideoFlags = new boolean[0];
  sampleQueuesEnabledStates = new boolean[0];
  mediaChunks = new ArrayList<>();
- maybeFinishPrepareRunnable = new Runnable() {
- @Override
- public void run() {
- maybeFinishPrepare();
- }
- };
+ maybeFinishPrepareRunnable =
+ new Runnable() {
+ @Override
+ public void run() {
+ maybeFinishPrepare();
+ }
+ };
+ onTracksEndedRunnable =
+ new Runnable() {
+ @Override
+ public void run() {
+ onTracksEnded();
+ }
+ };
  handler = new Handler();
  lastSeekPositionUs = positionUs;
  pendingResetPositionUs = positionUs;
@@ -166,8 +178,8 @@ public void continuePreparing() {
  */
  public void prepareSingleTrack(Format format) {
  track(0, C.TRACK_TYPE_UNKNOWN).format(format);
- sampleQueuesBuilt = true;
- maybeFinishPrepare();
+ tracksEnded = true;
+ onTracksEnded();
  }
 
  public void maybeThrowPrepareError() throws IOException {
@@ -178,6 +190,19 @@ public TrackGroupArray getTrackGroups() {
  return trackGroups;
  }
 
+ public int bindSampleQueueToSampleStream(int trackGroupIndex) {
+ int sampleQueueIndex = trackGroupToSampleQueueIndex[trackGroupIndex];
+ if (sampleQueueIndex == C.INDEX_UNSET) {
+ return C.INDEX_UNSET;
+ }
+ setSampleQueueEnabledState(sampleQueueIndex, true);
+ return sampleQueueIndex;
+ }
+
+ public void unbindSampleQueue(int trackGroupIndex) {
+ setSampleQueueEnabledState(trackGroupToSampleQueueIndex[trackGroupIndex], false);
+ }
+
  /**
  * Called by the parent {@link HlsMediaPeriod} when a track selection occurs.
  *
@@ -198,40 +223,42 @@ public TrackGroupArray getTrackGroups() {
  public boolean selectTracks(TrackSelection[] selections, boolean[] mayRetainStreamFlags,
  SampleStream[] streams, boolean[] streamResetFlags, long positionUs, boolean forceReset) {
  Assertions.checkState(prepared);
- int oldEnabledSampleQueueCount = enabledSampleQueueCount;
+ int oldEnabledTrackGroupCount = enabledTrackGroupCount;
  // Deselect old tracks.
  for (int i = 0; i < selections.length; i++) {
  if (streams[i] != null && (selections[i] == null || !mayRetainStreamFlags[i])) {
- setSampleQueueEnabledState(((HlsSampleStream) streams[i]).sampleQueueIndex, false);
+ enabledTrackGroupCount--;
+ ((HlsSampleStream) streams[i]).unbindSampleQueue();
  streams[i] = null;
  }
  }
  // We'll always need to seek if we're being forced to reset, or if this is a first selection to
  // a position other than the one we started preparing with, or if we're making a selection
  // having previously disabled all tracks.
- boolean seekRequired = forceReset
- || (seenFirstTrackSelection ? oldEnabledSampleQueueCount == 0
- : positionUs != lastSeekPositionUs);
+ boolean seekRequired =
+ forceReset
+ || (seenFirstTrackSelection
+ ? oldEnabledTrackGroupCount == 0
+ : positionUs != lastSeekPositionUs);
  // Get the old (i.e. current before the loop below executes) primary track selection. The new
  // primary selection will equal the old one unless it's changed in the loop.
  TrackSelection oldPrimaryTrackSelection = chunkSource.getTrackSelection();
  TrackSelection primaryTrackSelection = oldPrimaryTrackSelection;
  // Select new tracks.
  for (int i = 0; i < selections.length; i++) {
  if (streams[i] == null && selections[i] != null) {
+ enabledTrackGroupCount++;
  TrackSelection selection = selections[i];
  int trackGroupIndex = trackGroups.indexOf(selection.getTrackGroup());
- int sampleQueueIndex = trackGroupToSampleQueueIndex[trackGroupIndex];
- setSampleQueueEnabledState(sampleQueueIndex, true);
  if (trackGroupIndex == primaryTrackGroupIndex) {
  primaryTrackSelection = selection;
  chunkSource.selectTracks(selection);
  }
- streams[i] = new HlsSampleStream(this, sampleQueueIndex);
+ streams[i] = new HlsSampleStream(this, trackGroupIndex);
  streamResetFlags[i] = true;
  // If there's still a chance of avoiding a seek, try and seek within the sample queue.
- if (!seekRequired) {
- SampleQueue sampleQueue = sampleQueues[sampleQueueIndex];
+ if (sampleQueuesBuilt && !seekRequired) {
+ SampleQueue sampleQueue = sampleQueues[trackGroupToSampleQueueIndex[trackGroupIndex]];
  sampleQueue.rewind();
  // A seek can be avoided if we're able to advance to the current playback position in the
  // sample queue, or if we haven't read anything from the queue since the previous seek
@@ -243,14 +270,16 @@ public boolean selectTracks(TrackSelection[] selections, boolean[] mayRetainStre
  }
  }
 
- if (enabledSampleQueueCount == 0) {
+ if (enabledTrackGroupCount == 0) {
  chunkSource.reset();
  downstreamTrackFormat = null;
  mediaChunks.clear();
  if (loader.isLoading()) {
- // Discard as much as we can synchronously.
- for (SampleQueue sampleQueue : sampleQueues) {
- sampleQueue.discardToEnd();
+ if (sampleQueuesBuilt) {
+ // Discard as much as we can synchronously.
+ for (SampleQueue sampleQueue : sampleQueues) {
+ sampleQueue.discardToEnd();
+ }
  }
  loader.cancelLoading();
  } else {
@@ -297,6 +326,9 @@ public boolean selectTracks(TrackSelection[] selections, boolean[] mayRetainStre
  }
 
  public void discardBuffer(long positionUs, boolean toKeyframe) {
+ if (!sampleQueuesBuilt) {
+ return;
+ }
  int sampleQueueCount = sampleQueues.length;
  for (int i = 0; i < sampleQueueCount; i++) {
  sampleQueues[i].discardTo(positionUs, toKeyframe, sampleQueuesEnabledStates[i]);
@@ -314,7 +346,7 @@ public void discardBuffer(long positionUs, boolean toKeyframe) {
  public boolean seekToUs(long positionUs, boolean forceReset) {
  lastSeekPositionUs = positionUs;
  // If we're not forced to reset nor have a pending reset, see if we can seek within the buffer.
- if (!forceReset && !isPendingReset() && seekInsideBufferUs(positionUs)) {
+ if (sampleQueuesBuilt && !forceReset && !isPendingReset() && seekInsideBufferUs(positionUs)) {
  return false;
  }
  // We were unable to seek within the buffer, so need to reset.
@@ -426,9 +458,11 @@ public long getBufferedPositionUs() {
  if (lastCompletedMediaChunk != null) {
  bufferedPositionUs = Math.max(bufferedPositionUs, lastCompletedMediaChunk.endTimeUs);
  }
- for (SampleQueue sampleQueue : sampleQueues) {
- bufferedPositionUs = Math.max(bufferedPositionUs,
- sampleQueue.getLargestQueuedTimestampUs());
+ if (sampleQueuesBuilt) {
+ for (SampleQueue sampleQueue : sampleQueues) {
+ bufferedPositionUs =
+ Math.max(bufferedPositionUs, sampleQueue.getLargestQueuedTimestampUs());
+ }
  }
  return bufferedPositionUs;
  }
@@ -513,7 +547,7 @@ public void onLoadCanceled(Chunk loadable, long elapsedRealtimeMs, long loadDura
  loadable.endTimeUs, elapsedRealtimeMs, loadDurationMs, loadable.bytesLoaded());
  if (!released) {
  resetSampleQueues();
- if (enabledSampleQueueCount > 0) {
+ if (enabledTrackGroupCount > 0) {
  callback.onContinueLoadingRequested(this);
  }
  }
@@ -582,7 +616,7 @@ public TrackOutput track(int id, int type) {
  return sampleQueues[i];
  }
  }
- if (sampleQueuesBuilt) {
+ if (tracksEnded) {
  Log.w(TAG, "Unmapped track with id " + id + " of type " + type);
  return new DummyTrackOutput();
  }
@@ -603,8 +637,8 @@ public TrackOutput track(int id, int type) {
 
  @Override
  public void endTracks() {
- sampleQueuesBuilt = true;
- handler.post(maybeFinishPrepareRunnable);
+ tracksEnded = true;
+ handler.post(onTracksEndedRunnable);
  }
 
  @Override
@@ -616,9 +650,7 @@ public void seekMap(SeekMap seekMap) {
 
  @Override
  public void onUpstreamFormatChanged(Format format) {
- if (!prepared) {
- handler.post(maybeFinishPrepareRunnable);
- }
+ handler.post(maybeFinishPrepareRunnable);
  }
 
  // Called by the loading thread.
@@ -650,6 +682,11 @@ private void resetSampleQueues() {
  pendingResetUpstreamFormats = false;
  }
 
+ private void onTracksEnded() {
+ sampleQueuesBuilt = true;
+ maybeFinishPrepare();
+ }
+
  private void maybeFinishPrepare() {
  if (released || prepared || !sampleQueuesBuilt) {
  return;
@@ -739,14 +776,14 @@ private void buildTracks() {
  if (i == primaryExtractorTrackIndex) {
  Format[] formats = new Format[chunkSourceTrackCount];
  for (int j = 0; j < chunkSourceTrackCount; j++) {
- formats[j] = deriveFormat(chunkSourceTrackGroup.getFormat(j), sampleFormat);
+ formats[j] = deriveFormat(chunkSourceTrackGroup.getFormat(j), sampleFormat, true);
  }
  trackGroups[i] = new TrackGroup(formats);
  primaryTrackGroupIndex = i;
  } else {
  Format trackFormat = primaryExtractorTrackType == PRIMARY_TYPE_VIDEO
  && MimeTypes.isAudio(sampleFormat.sampleMimeType) ? muxedAudioFormat : null;
- trackGroups[i] = new TrackGroup(deriveFormat(trackFormat, sampleFormat));
+ trackGroups[i] = new TrackGroup(deriveFormat(trackFormat, sampleFormat, false));
  }
  }
  this.trackGroups = new TrackGroupArray(trackGroups);
@@ -761,7 +798,6 @@ private void buildTracks() {
  private void setSampleQueueEnabledState(int sampleQueueIndex, boolean enabledState) {
  Assertions.checkState(sampleQueuesEnabledStates[sampleQueueIndex] != enabledState);
  sampleQueuesEnabledStates[sampleQueueIndex] = enabledState;
- enabledSampleQueueCount = enabledSampleQueueCount + (enabledState ? 1 : -1);
  }
 
  private HlsMediaChunk getLastMediaChunk() {
@@ -797,22 +833,30 @@ private boolean seekInsideBufferUs(long positionUs) {
  }
 
  /**
- * Derives a track format corresponding to a given container format, by combining it with sample
- * level information obtained from the samples.
+ * Derives a track format using master playlist and sample format information.
  *
- * @param containerFormat The container format for which the track format should be derived.
- * @param sampleFormat A sample format from which to obtain sample level information.
+ * @param playlistFormat The format information obtained from the master playlist.
+ * @param sampleFormat The format information obtained from the samples.
+ * @param propagateBitrate Whether the bitrate from the playlist format should be included in the
+ * derived format.
  * @return The derived track format.
  */
- private static Format deriveFormat(Format containerFormat, Format sampleFormat) {
- if (containerFormat == null) {
+ private static Format deriveFormat(
+ Format playlistFormat, Format sampleFormat, boolean propagateBitrate) {
+ if (playlistFormat == null) {
  return sampleFormat;
  }
+ int bitrate = propagateBitrate ? playlistFormat.bitrate : Format.NO_VALUE;
  int sampleTrackType = MimeTypes.getTrackType(sampleFormat.sampleMimeType);
- String codecs = Util.getCodecsOfType(containerFormat.codecs, sampleTrackType);
- return sampleFormat.copyWithContainerInfo(containerFormat.id, codecs, containerFormat.bitrate,
- containerFormat.width, containerFormat.height, containerFormat.selectionFlags,
- containerFormat.language);
+ String codecs = Util.getCodecsOfType(playlistFormat.codecs, sampleTrackType);
+ return sampleFormat.copyWithContainerInfo(
+ playlistFormat.id,
+ codecs,
+ bitrate,
+ playlistFormat.width,
+ playlistFormat.height,
+ playlistFormat.selectionFlags,
+ playlistFormat.language);
  }
 
  private static boolean isMediaChunk(Chunk chunk) {