Make onOutputFormat nullable

- This is to make sure we know about all the tracks before initializing
the SamplePipelines. This allows to set the muxer and the fallback
listener track count before the SamplePipelines are built.
- As a result, the test files had to be updated because the order in
which the tracks are written has changed.
- The ImageAssetLoader also had to be updated to call onOutputFormat
repeatedly until it returns a non-null SampleConsumer.
- Also fix the trackCount sent to the muxer and fallback listener. The
correct track count can be computed now that we know about all the
tracks before building the SamplePipelines.

PiperOrigin-RevId: 514426123

library/transformer/src/main/java/com/google/android/exoplayer2/transformer/AssetLoader.java

@@ -21,6 +21,7 @@ import static java.lang.annotation.ElementType.TYPE_USE;
 import android.os.Looper;
 import androidx.annotation.IntDef;
 import androidx.annotation.IntRange;
+import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.Format;
 import com.google.common.collect.ImmutableMap;
 import java.lang.annotation.Documented;
@@ -112,17 +113,21 @@ public interface AssetLoader {
      * Called when the {@link Format} of samples that will be output by the {@link AssetLoader} is
      * known.
      *
-     * <p>Must be called once per {@linkplain #onTrackCount declared} track, and only after that
-     * track has been {@link #onTrackAdded added}.
+     * <p>Must be called after the corresponding track has been {@link #onTrackAdded added}.
+     *
+     * <p>For each {@link #onTrackAdded added} track, this method must be called regularly until the
+     * returned {@link SampleConsumer} is non-null.
      *
      * <p>Must be called from the thread that will be used to call the returned {@link
      * SampleConsumer}'s methods. This thread must be the same for all formats output, and is
      * generally different from the one used to access the {@link AssetLoader} methods.
      *
      * @param format The {@link Format} of samples that will be output.
-     * @return The {@link SampleConsumer} of samples of the given {@link Format}.
+     * @return The {@link SampleConsumer} of samples of the given {@link Format}, or {@code null} if
+     *     it could not be retrieved yet.
      * @throws ExportException If an error occurs configuring the {@link SampleConsumer}.
      */
+    @Nullable
     SampleConsumer onOutputFormat(Format format) throws ExportException;
 
     /**

library/transformer/src/main/java/com/google/android/exoplayer2/transformer/CompositeAssetLoader.java

@@ -235,25 +235,31 @@ import java.util.concurrent.atomic.AtomicInteger;
     return decodeOutput;
   }
 
+  @Nullable
   @Override
   public SampleConsumer onOutputFormat(Format format) throws ExportException {
     @C.TrackType int trackType = getProcessedTrackType(format.sampleMimeType);
     SampleConsumer sampleConsumer;
     if (currentMediaItemIndex.get() == 0) {
-      sampleConsumer =
-          new SampleConsumerWrapper(compositeAssetLoaderListener.onOutputFormat(format));
+      @Nullable
+      SampleConsumer wrappedSampleConsumer = compositeAssetLoaderListener.onOutputFormat(format);
+      if (wrappedSampleConsumer == null) {
+        return null;
+      }
+      sampleConsumer = new SampleConsumerWrapper(wrappedSampleConsumer);
       sampleConsumersByTrackType.put(trackType, sampleConsumer);
 
       if (forceAudioTrack && nonEndedTracks.get() == 1 && trackType == C.TRACK_TYPE_VIDEO) {
-        sampleConsumersByTrackType.put(
-            C.TRACK_TYPE_AUDIO,
-            new SampleConsumerWrapper(
+        SampleConsumer wrappedAudioSampleConsumer =
+            checkStateNotNull(
                 compositeAssetLoaderListener.onOutputFormat(
                     FORCE_AUDIO_TRACK_FORMAT
                         .buildUpon()
                         .setSampleMimeType(MimeTypes.AUDIO_RAW)
                         .setPcmEncoding(C.ENCODING_PCM_16BIT)
-                        .build())));
+                        .build()));
+        sampleConsumersByTrackType.put(
+            C.TRACK_TYPE_AUDIO, new SampleConsumerWrapper(wrappedAudioSampleConsumer));
       }
     } else {
       // TODO(b/270533049): Remove the check below when implementing blank video frames generation.

library/transformer/src/main/java/com/google/android/exoplayer2/transformer/ExoAssetLoaderBaseRenderer.java

@@ -46,6 +46,7 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
   protected @MonotonicNonNull Codec decoder;
   protected boolean isEnded;
   private @MonotonicNonNull Format inputFormat;
+  private @MonotonicNonNull Format outputFormat;
 
   private final TransformerMediaClock mediaClock;
   private final AssetLoader.Listener assetLoaderListener;
@@ -244,19 +245,26 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
       return true;
     }
 
+    if (outputFormat == null) {
       if (decoder != null
           && getProcessedTrackType(inputFormat.sampleMimeType) == C.TRACK_TYPE_AUDIO) {
         @Nullable Format decoderOutputFormat = decoder.getOutputFormat();
         if (decoderOutputFormat == null) {
           return false;
         }
-      sampleConsumer = assetLoaderListener.onOutputFormat(decoderOutputFormat);
+        outputFormat = decoderOutputFormat;
       } else {
-      // TODO(b/237674316): Move surface creation out of video sampleConsumer. Init decoder and get
-      // decoderOutput Format before init sampleConsumer.
-      sampleConsumer = assetLoaderListener.onOutputFormat(inputFormat);
+        // TODO(b/237674316): Move surface creation out of video sampleConsumer. Init decoder and
+        // get decoderOutput Format before init sampleConsumer.
+        outputFormat = inputFormat;
+      }
     }
 
+    SampleConsumer sampleConsumer = assetLoaderListener.onOutputFormat(outputFormat);
+    if (sampleConsumer == null) {
+      return false;
+    }
+    this.sampleConsumer = sampleConsumer;
     return true;
   }
 

library/transformer/src/main/java/com/google/android/exoplayer2/transformer/ImageAssetLoader.java

@@ -22,14 +22,18 @@ import static com.google.android.exoplayer2.transformer.Transformer.PROGRESS_STA
 import static com.google.android.exoplayer2.transformer.Transformer.PROGRESS_STATE_NOT_STARTED;
 import static com.google.android.exoplayer2.util.Assertions.checkNotNull;
 import static com.google.android.exoplayer2.util.Assertions.checkState;
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
 
 import android.content.Context;
 import android.graphics.Bitmap;
 import android.os.Looper;
+import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.MediaItem;
+import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DataSourceBitmapLoader;
+import com.google.android.exoplayer2.upstream.DefaultDataSource;
 import com.google.android.exoplayer2.util.BitmapLoader;
 import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.common.collect.ImmutableMap;
@@ -37,6 +41,8 @@ import com.google.common.util.concurrent.FutureCallback;
 import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.common.util.concurrent.MoreExecutors;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
 
 /** An {@link AssetLoader} implementation that loads images into {@link Bitmap} instances. */
 public final class ImageAssetLoader implements AssetLoader {
@@ -59,26 +65,36 @@ public final class ImageAssetLoader implements AssetLoader {
 
   public static final String MIME_TYPE_IMAGE_ALL = MimeTypes.BASE_TYPE_IMAGE + "/*";
 
-  private final Context context;
+  private static final int QUEUE_BITMAP_INTERVAL_MS = 10;
+
   private final EditedMediaItem editedMediaItem;
+  private final DataSource.Factory dataSourceFactory;
   private final Listener listener;
+  private final ScheduledExecutorService scheduledExecutorService;
 
   private @Transformer.ProgressState int progressState;
-  private int progress;
+
+  private volatile int progress;
 
   private ImageAssetLoader(Context context, EditedMediaItem editedMediaItem, Listener listener) {
-    this.context = context;
+    checkState(editedMediaItem.durationUs != C.TIME_UNSET);
+    checkState(editedMediaItem.frameRate != C.RATE_UNSET_INT);
     this.editedMediaItem = editedMediaItem;
+    dataSourceFactory = new DefaultDataSource.Factory(context);
     this.listener = listener;
-
+    scheduledExecutorService = Executors.newSingleThreadScheduledExecutor();
     progressState = PROGRESS_STATE_NOT_STARTED;
   }
 
   @Override
+  @SuppressWarnings("FutureReturnValueIgnored")
   public void start() {
     progressState = PROGRESS_STATE_AVAILABLE;
+    listener.onDurationUs(editedMediaItem.durationUs);
     listener.onTrackCount(1);
-    BitmapLoader bitmapLoader = new DataSourceBitmapLoader(context);
+    BitmapLoader bitmapLoader =
+        new DataSourceBitmapLoader(
+            MoreExecutors.listeningDecorator(scheduledExecutorService), dataSourceFactory);
     MediaItem.LocalConfiguration localConfiguration =
         checkNotNull(editedMediaItem.mediaItem.localConfiguration);
     ListenableFuture<Bitmap> future = bitmapLoader.loadBitmap(localConfiguration.uri);
@@ -100,21 +116,10 @@ public final class ImageAssetLoader implements AssetLoader {
                   SUPPORTED_OUTPUT_TYPE_DECODED,
                   /* streamStartPositionUs= */ 0,
                   /* streamOffsetUs= */ 0);
-              SampleConsumer sampleConsumer = listener.onOutputFormat(format);
-
-              checkState(editedMediaItem.durationUs != C.TIME_UNSET);
-              checkState(editedMediaItem.frameRate != C.RATE_UNSET_INT);
-              // TODO(b/262693274): consider using listener.onDurationUs() or the MediaItem change
-              //    callback (when it's added) rather than setting duration here.
-              sampleConsumer.queueInputBitmap(
-                  bitmap, editedMediaItem.durationUs, editedMediaItem.frameRate);
-              sampleConsumer.signalEndOfVideoInput();
-            } catch (ExportException e) {
-              listener.onError(e);
+              scheduledExecutorService.submit(() -> queueBitmapInternal(bitmap, format));
             } catch (RuntimeException e) {
               listener.onError(ExportException.createForAssetLoader(e, ERROR_CODE_UNSPECIFIED));
             }
-            progress = 100;
           }
 
           @Override
@@ -122,7 +127,7 @@ public final class ImageAssetLoader implements AssetLoader {
             listener.onError(ExportException.createForAssetLoader(t, ERROR_CODE_IO_UNSPECIFIED));
           }
         },
-        MoreExecutors.directExecutor());
+        scheduledExecutorService);
   }
 
   @Override
@@ -141,5 +146,28 @@ public final class ImageAssetLoader implements AssetLoader {
   @Override
   public void release() {
     progressState = PROGRESS_STATE_NOT_STARTED;
+    scheduledExecutorService.shutdownNow();
+  }
+
+  @SuppressWarnings("FutureReturnValueIgnored")
+  private void queueBitmapInternal(Bitmap bitmap, Format format) {
+    try {
+      @Nullable SampleConsumer sampleConsumer = listener.onOutputFormat(format);
+      if (sampleConsumer == null) {
+        scheduledExecutorService.schedule(
+            () -> queueBitmapInternal(bitmap, format), QUEUE_BITMAP_INTERVAL_MS, MILLISECONDS);
+        return;
+      }
+      // TODO(b/262693274): consider using listener.onDurationUs() or the MediaItem change
+      //    callback rather than setting duration here.
+      sampleConsumer.queueInputBitmap(
+          bitmap, editedMediaItem.durationUs, editedMediaItem.frameRate);
+      sampleConsumer.signalEndOfVideoInput();
+      progress = 100;
+    } catch (ExportException e) {
+      listener.onError(e);
+    } catch (RuntimeException e) {
+      listener.onError(ExportException.createForAssetLoader(e, ERROR_CODE_UNSPECIFIED));
+    }
   }
 }

library/transformer/src/main/java/com/google/android/exoplayer2/transformer/TransformerInternal.java

@@ -54,6 +54,7 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
@@ -99,8 +100,10 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
   private final HandlerThread internalHandlerThread;
   private final HandlerWrapper internalHandler;
   private final List<CompositeAssetLoader> compositeAssetLoaders;
-  private final AtomicInteger totalInputTrackCount;
-  private final AtomicInteger unreportedInputTrackCounts;
+  private final AtomicInteger trackCountsToReport;
+  private final AtomicInteger tracksToAdd;
+  private final AtomicBoolean outputHasAudio;
+  private final AtomicBoolean outputHasVideo;
   private final List<SamplePipeline> samplePipelines;
   private final MuxerWrapper muxerWrapper;
   private final ConditionVariable transformerConditionVariable;
@@ -153,8 +156,10 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
               compositeAssetLoaderListener,
               clock));
     }
-    totalInputTrackCount = new AtomicInteger();
-    unreportedInputTrackCounts = new AtomicInteger(composition.sequences.size());
+    trackCountsToReport = new AtomicInteger(composition.sequences.size());
+    tracksToAdd = new AtomicInteger();
+    outputHasAudio = new AtomicBoolean();
+    outputHasVideo = new AtomicBoolean();
     samplePipelines = new ArrayList<>();
     transformerConditionVariable = new ConditionVariable();
     exportResultBuilder = new ExportResult.Builder();
@@ -435,12 +440,8 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
                 ERROR_CODE_FAILED_RUNTIME_CHECK));
         return;
       }
-      totalInputTrackCount.addAndGet(trackCount);
-      unreportedInputTrackCounts.decrementAndGet();
-      if (unreportedInputTrackCounts.get() == 0) {
-        muxerWrapper.setTrackCount(totalInputTrackCount.get());
-        fallbackListener.setTrackCount(totalInputTrackCount.get());
-      }
+      trackCountsToReport.decrementAndGet();
+      tracksToAdd.addAndGet(trackCount);
     }
 
     @Override
@@ -449,21 +450,38 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
         @AssetLoader.SupportedOutputTypes int supportedOutputTypes,
         long streamStartPositionUs,
         long streamOffsetUs) {
+      @C.TrackType
+      int trackType = getProcessedTrackType(firstAssetLoaderInputFormat.sampleMimeType);
       AddedTrackInfo trackInfo =
           new AddedTrackInfo(
               firstAssetLoaderInputFormat,
               supportedOutputTypes,
               streamStartPositionUs,
               streamOffsetUs);
+      addedTrackInfoByTrackType.put(trackType, trackInfo);
 
-      addedTrackInfoByTrackType.put(
-          getProcessedTrackType(firstAssetLoaderInputFormat.sampleMimeType), trackInfo);
+      if (trackType == C.TRACK_TYPE_AUDIO) {
+        outputHasAudio.set(true);
+      } else {
+        outputHasVideo.set(true);
+      }
+      if (trackCountsToReport.get() == 0 && tracksToAdd.get() == 1) {
+        int outputTrackCount = (outputHasAudio.get() ? 1 : 0) + (outputHasVideo.get() ? 1 : 0);
+        muxerWrapper.setTrackCount(outputTrackCount);
+        fallbackListener.setTrackCount(outputTrackCount);
+      }
+      tracksToAdd.decrementAndGet();
 
       return trackInfo.shouldTranscode;
     }
 
+    @Nullable
     @Override
     public SampleConsumer onOutputFormat(Format assetLoaderOutputFormat) throws ExportException {
+      if (trackCountsToReport.get() > 0 || tracksToAdd.get() > 0) {
+        return null;
+      }
+
       @C.TrackType int trackType = getProcessedTrackType(assetLoaderOutputFormat.sampleMimeType);
       AddedTrackInfo trackInfo = checkStateNotNull(addedTrackInfoByTrackType.get(trackType));
       SamplePipeline samplePipeline = getSamplePipeline(assetLoaderOutputFormat, trackInfo);

testdata/src/test/assets/transformerdumps/mkv/sample_with_srt.mkv.dump

 format 0:
-  sampleMimeType = audio/mp4a-latm
-  channelCount = 1
-  sampleRate = 44100
-  pcmEncoding = 2
-format 1:
   id = 1
   sampleMimeType = video/avc
   codecs = avc1.640034
@@ -14,356 +9,361 @@ format 1:
   initializationData:
     data = length 30, hash F6F3D010
     data = length 10, hash 7A0D0F2B
+format 1:
+  sampleMimeType = audio/mp4a-latm
+  channelCount = 1
+  sampleRate = 44100
+  pcmEncoding = 2
 sample:
   trackIndex = 1
-  dataHashCode = -252482306
-  size = 36477
-  isKeyFrame = true
-  presentationTimeUs = 0
-sample:
-  trackIndex = 1
-  dataHashCode = 67864034
-  size = 5341
-  isKeyFrame = false
-  presentationTimeUs = 67000
-sample:
-  trackIndex = 1
-  dataHashCode = 897273234
-  size = 596
-  isKeyFrame = false
-  presentationTimeUs = 33000
-sample:
-  trackIndex = 1
-  dataHashCode = -1549870586
-  size = 7704
-  isKeyFrame = false
-  presentationTimeUs = 200000
-sample:
-  trackIndex = 1
-  dataHashCode = 672384813
-  size = 989
-  isKeyFrame = false
-  presentationTimeUs = 133000
-sample:
-  trackIndex = 1
-  dataHashCode = -988996493
-  size = 721
-  isKeyFrame = false
-  presentationTimeUs = 100000
-sample:
-  trackIndex = 1
-  dataHashCode = 1711151377
-  size = 519
-  isKeyFrame = false
-  presentationTimeUs = 167000
-sample:
-  trackIndex = 1
-  dataHashCode = -506806036
-  size = 6160
-  isKeyFrame = false
-  presentationTimeUs = 333000
-sample:
-  trackIndex = 1
-  dataHashCode = 1902167649
-  size = 953
-  isKeyFrame = false
-  presentationTimeUs = 267000
-sample:
-  trackIndex = 1
-  dataHashCode = 2054873212
-  size = 620
-  isKeyFrame = false
-  presentationTimeUs = 233000
-sample:
-  trackIndex = 0
   dataHashCode = 555688582
   size = 416
   isKeyFrame = true
   presentationTimeUs = 0
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 2000837254
   size = 418
   isKeyFrame = true
   presentationTimeUs = 4717
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1593942879
   size = 418
   isKeyFrame = true
   presentationTimeUs = 9456
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 587837542
   size = 418
   isKeyFrame = true
   presentationTimeUs = 14196
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1836423877
   size = 418
   isKeyFrame = true
   presentationTimeUs = 18935
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 874705099
   size = 418
   isKeyFrame = true
   presentationTimeUs = 23674
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -269206181
   size = 418
   isKeyFrame = true
   presentationTimeUs = 28413
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -58682425
   size = 418
   isKeyFrame = true
   presentationTimeUs = 33152
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -859796970
   size = 418
   isKeyFrame = true
   presentationTimeUs = 37892
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 711911523
   size = 418
   isKeyFrame = true
   presentationTimeUs = 42631
 sample:
   trackIndex = 0
+  dataHashCode = -252482306
+  size = 36477
+  isKeyFrame = true
+  presentationTimeUs = 0
+sample:
+  trackIndex = 0
+  dataHashCode = 67864034
+  size = 5341
+  isKeyFrame = false
+  presentationTimeUs = 67000
+sample:
+  trackIndex = 0
+  dataHashCode = 897273234
+  size = 596
+  isKeyFrame = false
+  presentationTimeUs = 33000
+sample:
+  trackIndex = 0
+  dataHashCode = -1549870586
+  size = 7704
+  isKeyFrame = false
+  presentationTimeUs = 200000
+sample:
+  trackIndex = 0
+  dataHashCode = 672384813
+  size = 989
+  isKeyFrame = false
+  presentationTimeUs = 133000
+sample:
+  trackIndex = 0
+  dataHashCode = -988996493
+  size = 721
+  isKeyFrame = false
+  presentationTimeUs = 100000
+sample:
+  trackIndex = 0
+  dataHashCode = 1711151377
+  size = 519
+  isKeyFrame = false
+  presentationTimeUs = 167000
+sample:
+  trackIndex = 0
+  dataHashCode = -506806036
+  size = 6160
+  isKeyFrame = false
+  presentationTimeUs = 333000
+sample:
+  trackIndex = 0
+  dataHashCode = 1902167649
+  size = 953
+  isKeyFrame = false
+  presentationTimeUs = 267000
+sample:
+  trackIndex = 0
+  dataHashCode = 2054873212
+  size = 620
+  isKeyFrame = false
+  presentationTimeUs = 233000
+sample:
+  trackIndex = 1
   dataHashCode = -694513071
   size = 418
   isKeyFrame = true
   presentationTimeUs = 47370
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1124371059
   size = 418
   isKeyFrame = true
   presentationTimeUs = 52109
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 297166745
   size = 418
   isKeyFrame = true
   presentationTimeUs = 56849
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -937110638
   size = 418
   isKeyFrame = true
   presentationTimeUs = 61588
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1050158990
   size = 418
   isKeyFrame = true
   presentationTimeUs = 66327
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 1109510229
   size = 418
   isKeyFrame = true
   presentationTimeUs = 71066
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 1297086772
   size = 418
   isKeyFrame = true
   presentationTimeUs = 75805
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1739939803
   size = 418
   isKeyFrame = true
   presentationTimeUs = 80545
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1149727930
   size = 418
   isKeyFrame = true
   presentationTimeUs = 85284
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1627652713
   size = 418
   isKeyFrame = true
   presentationTimeUs = 90023
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1556608231
   size = 405
   isKeyFrame = false
   presentationTimeUs = 300000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1648978019
   size = 4852
   isKeyFrame = false
   presentationTimeUs = 433000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -484808327
   size = 547
   isKeyFrame = false
   presentationTimeUs = 400000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -20706048
   size = 570
   isKeyFrame = false
   presentationTimeUs = 367000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 2085064574
   size = 5525
   isKeyFrame = false
   presentationTimeUs = 567000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -637074022
   size = 1082
   isKeyFrame = false
   presentationTimeUs = 500000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1824027029
   size = 807
   isKeyFrame = false
   presentationTimeUs = 467000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1701945306
   size = 744
   isKeyFrame = false
   presentationTimeUs = 533000
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -551926260
   size = 418
   isKeyFrame = true
   presentationTimeUs = 94762
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 45987178
   size = 418
   isKeyFrame = true
   presentationTimeUs = 99502
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -903675808
   size = 418
   isKeyFrame = true
   presentationTimeUs = 104241
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -755916991
   size = 418
   isKeyFrame = true
   presentationTimeUs = 108980
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1355207303
   size = 418
   isKeyFrame = true
   presentationTimeUs = 113719
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -975703389
   size = 418
   isKeyFrame = true
   presentationTimeUs = 118459
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 1933194670
   size = 418
   isKeyFrame = true
   presentationTimeUs = 123198
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -565778989
   size = 418
   isKeyFrame = true
   presentationTimeUs = 127937
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 1454083383
   size = 418
   isKeyFrame = true
   presentationTimeUs = 132676
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -952425536
   size = 4732
   isKeyFrame = false
   presentationTimeUs = 700000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1978031576
   size = 1004
   isKeyFrame = false
   presentationTimeUs = 633000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -2128215508
   size = 794
   isKeyFrame = false
   presentationTimeUs = 600000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -259850011
   size = 645
   isKeyFrame = false
   presentationTimeUs = 667000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1920983928
   size = 2684
   isKeyFrame = false
   presentationTimeUs = 833000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1100642337
   size = 787
   isKeyFrame = false
   presentationTimeUs = 767000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1544917830
   size = 649
   isKeyFrame = false
   presentationTimeUs = 733000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -116205995
   size = 509
   isKeyFrame = false
   presentationTimeUs = 800000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 696343585
   size = 1226
   isKeyFrame = false
   presentationTimeUs = 967000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -644371190
   size = 898
   isKeyFrame = false
   presentationTimeUs = 900000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1606273467
   size = 476
   isKeyFrame = false
   presentationTimeUs = 867000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -571265861
   size = 486
   isKeyFrame = false

testdata/src/test/assets/transformerdumps/mp4/sample_sef_slow_motion.mp4.dump

 format 0:
-  sampleMimeType = audio/mp4a-latm
-  channelCount = 2
-  sampleRate = 12000
-  pcmEncoding = 2
-format 1:
   id = 2
   sampleMimeType = video/avc
   codecs = avc1.64000D
@@ -15,332 +10,337 @@ format 1:
   initializationData:
     data = length 33, hash D3FB879D
     data = length 10, hash 7A0D0F2B
+format 1:
+  sampleMimeType = audio/mp4a-latm
+  channelCount = 2
+  sampleRate = 12000
+  pcmEncoding = 2
 sample:
   trackIndex = 1
+  dataHashCode = -212376212
+  size = 20
+  isKeyFrame = true
+  presentationTimeUs = 0
+sample:
+  trackIndex = 1
+  dataHashCode = -1948569090
+  size = 72
+  isKeyFrame = true
+  presentationTimeUs = 417
+sample:
+  trackIndex = 1
+  dataHashCode = -1316750072
+  size = 84
+  isKeyFrame = true
+  presentationTimeUs = 1917
+sample:
+  trackIndex = 1
+  dataHashCode = 1016428949
+  size = 88
+  isKeyFrame = true
+  presentationTimeUs = 3667
+sample:
+  trackIndex = 1
+  dataHashCode = -1127325245
+  size = 96
+  isKeyFrame = true
+  presentationTimeUs = 5500
+sample:
+  trackIndex = 1
+  dataHashCode = 1148147726
+  size = 92
+  isKeyFrame = true
+  presentationTimeUs = 7500
+sample:
+  trackIndex = 0
   dataHashCode = 1949079733
   size = 5446
   isKeyFrame = true
   presentationTimeUs = 0
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1397194508
   size = 125
   isKeyFrame = false
   presentationTimeUs = 14000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1147159698
   size = 147
   isKeyFrame = false
   presentationTimeUs = 47333
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 524634358
   size = 149
   isKeyFrame = false
   presentationTimeUs = 80667
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 2031178347
   size = 149
   isKeyFrame = false
   presentationTimeUs = 114000
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -625462168
   size = 169
   isKeyFrame = false
   presentationTimeUs = 147333
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -973299745
   size = 126
   isKeyFrame = false
   presentationTimeUs = 180667
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -788426325
   size = 120
   isKeyFrame = false
   presentationTimeUs = 228042
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 2009515523
   size = 126
   isKeyFrame = false
   presentationTimeUs = 244708
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -874600600
   size = 1180
   isKeyFrame = false
   presentationTimeUs = 334083
 sample:
-  trackIndex = 0
-  dataHashCode = -212376212
-  size = 20
-  isKeyFrame = true
-  presentationTimeUs = 0
-sample:
-  trackIndex = 0
-  dataHashCode = -1948569090
-  size = 72
-  isKeyFrame = true
-  presentationTimeUs = 417
-sample:
-  trackIndex = 0
-  dataHashCode = -1316750072
-  size = 84
-  isKeyFrame = true
-  presentationTimeUs = 1917
-sample:
-  trackIndex = 0
-  dataHashCode = 1016428949
-  size = 88
-  isKeyFrame = true
-  presentationTimeUs = 3667
-sample:
-  trackIndex = 0
-  dataHashCode = -1127325245
-  size = 96
-  isKeyFrame = true
-  presentationTimeUs = 5500
-sample:
-  trackIndex = 0
-  dataHashCode = 1148147726
-  size = 92
-  isKeyFrame = true
-  presentationTimeUs = 7500
-sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -2125685540
   size = 76
   isKeyFrame = true
   presentationTimeUs = 9417
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 473329679
   size = 24
   isKeyFrame = true
   presentationTimeUs = 11000
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 240990900
   size = 176
   isKeyFrame = true
   presentationTimeUs = 11500
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 777637182
   size = 196
   isKeyFrame = true
   presentationTimeUs = 15167
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 1872106264
   size = 180
   isKeyFrame = true
   presentationTimeUs = 19250
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1520711499
   size = 140
   isKeyFrame = true
   presentationTimeUs = 23000
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 1580199067
   size = 232
   isKeyFrame = true
   presentationTimeUs = 25917
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 475464086
   size = 184
   isKeyFrame = true
   presentationTimeUs = 30750
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -211754132
   size = 172
   isKeyFrame = true
   presentationTimeUs = 34584
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 1236547164
   size = 172
   isKeyFrame = true
   presentationTimeUs = 38167
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -2064216186
   size = 188
   isKeyFrame = true
   presentationTimeUs = 41750
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 984869991
   size = 216
   isKeyFrame = false
   presentationTimeUs = 267416
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 2106811176
   size = 119
   isKeyFrame = false
   presentationTimeUs = 234083
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1981166365
   size = 145
   isKeyFrame = false
   presentationTimeUs = 300750
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1234592714
   size = 1274
   isKeyFrame = false
   presentationTimeUs = 467416
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -13135608
   size = 190
   isKeyFrame = false
   presentationTimeUs = 400750
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1840621658
   size = 107
   isKeyFrame = false
   presentationTimeUs = 367416
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1637734271
   size = 125
   isKeyFrame = false
   presentationTimeUs = 434083
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -682950885
   size = 260
   isKeyFrame = true
   presentationTimeUs = 45667
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 1301206627
   size = 236
   isKeyFrame = true
   presentationTimeUs = 51084
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 256580525
   size = 236
   isKeyFrame = true
   presentationTimeUs = 56000
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1086601304
   size = 236
   isKeyFrame = true
   presentationTimeUs = 60917
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -2046131588
   size = 224
   isKeyFrame = true
   presentationTimeUs = 65834
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 1550955865
   size = 224
   isKeyFrame = true
   presentationTimeUs = 70500
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -274800552
   size = 220
   isKeyFrame = true
   presentationTimeUs = 75167
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = 382420909
   size = 224
   isKeyFrame = true
   presentationTimeUs = 79750
 sample:
-  trackIndex = 0
+  trackIndex = 1
   dataHashCode = -1431575865
   size = 232
   isKeyFrame = true
   presentationTimeUs = 84417
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 2112365658
   size = 1109
   isKeyFrame = false
   presentationTimeUs = 600750
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -968901399
   size = 250
   isKeyFrame = false
   presentationTimeUs = 534083
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1184738023
   size = 124
   isKeyFrame = false
   presentationTimeUs = 500750
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1756300509
   size = 134
   isKeyFrame = false
   presentationTimeUs = 567416
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 823429273
   size = 1201
   isKeyFrame = false
   presentationTimeUs = 734083
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 651718599
   size = 213
   isKeyFrame = false
   presentationTimeUs = 667416
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 846349953
   size = 125
   isKeyFrame = false
   presentationTimeUs = 634083
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = 1331153462
   size = 114
   isKeyFrame = false
   presentationTimeUs = 700750
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -73358172
   size = 1010
   isKeyFrame = false
   presentationTimeUs = 867416
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1395269253
   size = 209
   isKeyFrame = false
   presentationTimeUs = 800750
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -1001367604
   size = 139
   isKeyFrame = false
   presentationTimeUs = 767416
 sample:
-  trackIndex = 1
+  trackIndex = 0
   dataHashCode = -122569918
   size = 138
   isKeyFrame = false