Merge pull request #9893 from moneytoo:mkv-vtt

PiperOrigin-RevId: 424382031

RELEASENOTES.md

@@ -63,6 +63,8 @@
         the `Format#id` field of the subtitle track created from the
         the `Format#id` field of the subtitle track created from the
         configuration
         configuration
         ([#9673](https://github.com/google/ExoPlayer/issues/9673)).
         ([#9673](https://github.com/google/ExoPlayer/issues/9673)).
+    *   Add basic support for WebVTT subtitles in Matroska containers
+        ([#9886](https://github.com/google/ExoPlayer/issues/9886)).
 *   DRM:
 *   DRM:
     *   Remove `playbackLooper` from `DrmSessionManager.(pre)acquireSession`.
     *   Remove `playbackLooper` from `DrmSessionManager.(pre)acquireSession`.
         When a `DrmSessionManager` is used by an app in a custom `MediaSource`,
         When a `DrmSessionManager` is used by an app in a custom `MediaSource`,

library/core/src/test/java/com/google/android/exoplayer2/e2etest/MkvPlaybackTest.java

@@ -48,7 +48,9 @@ public final class MkvPlaybackTest {
         "sample_with_ssa_subtitles.mkv",
         "sample_with_ssa_subtitles.mkv",
         "sample_with_null_terminated_ssa_subtitles.mkv",
         "sample_with_null_terminated_ssa_subtitles.mkv",
         "sample_with_srt.mkv",
         "sample_with_srt.mkv",
-        "sample_with_null_terminated_srt.mkv");
+        "sample_with_null_terminated_srt.mkv",
+        "sample_with_vtt_subtitles.mkv",
+        "sample_with_null_terminated_vtt_subtitles.mkv");
   }
   }
 
 
   @ParameterizedRobolectricTestRunner.Parameter public String inputFile;
   @ParameterizedRobolectricTestRunner.Parameter public String inputFile;

library/extractor/src/main/java/com/google/android/exoplayer2/extractor/mkv/MatroskaExtractor.java

@@ -138,6 +138,7 @@ public class MatroskaExtractor implements Extractor {
   private static final String CODEC_ID_PCM_FLOAT = "A_PCM/FLOAT/IEEE";
   private static final String CODEC_ID_PCM_FLOAT = "A_PCM/FLOAT/IEEE";
   private static final String CODEC_ID_SUBRIP = "S_TEXT/UTF8";
   private static final String CODEC_ID_SUBRIP = "S_TEXT/UTF8";
   private static final String CODEC_ID_ASS = "S_TEXT/ASS";
   private static final String CODEC_ID_ASS = "S_TEXT/ASS";
+  private static final String CODEC_ID_VTT = "S_TEXT/WEBVTT";
   private static final String CODEC_ID_VOBSUB = "S_VOBSUB";
   private static final String CODEC_ID_VOBSUB = "S_VOBSUB";
   private static final String CODEC_ID_PGS = "S_HDMV/PGS";
   private static final String CODEC_ID_PGS = "S_HDMV/PGS";
   private static final String CODEC_ID_DVBSUB = "S_DVBSUB";
   private static final String CODEC_ID_DVBSUB = "S_DVBSUB";
@@ -323,6 +324,32 @@ public class MatroskaExtractor implements Extractor {
   /** The format of an SSA timecode. */
   /** The format of an SSA timecode. */
   private static final String SSA_TIMECODE_FORMAT = "%01d:%02d:%02d:%02d";
   private static final String SSA_TIMECODE_FORMAT = "%01d:%02d:%02d:%02d";
 
 
+  /**
+   * A template for the prefix that must be added to each VTT sample.
+   *
+   * <p>The display time of each subtitle is passed as {@code timeUs} to {@link
+   * TrackOutput#sampleMetadata}. The start and end timecodes in this template are relative to
+   * {@code timeUs}. Hence the start timecode is always zero. The 12 byte end timecode starting at
+   * {@link #VTT_PREFIX_END_TIMECODE_OFFSET} is set to a placeholder value, and must be replaced
+   * with the duration of the subtitle.
+   *
+   * <p>Equivalent to the UTF-8 string: "WEBVTT\n\n00:00:00.000 --> 00:00:00.000\n".
+   */
+  private static final byte[] VTT_PREFIX =
+      new byte[] {
+        87, 69, 66, 86, 84, 84, 10, 10, 48, 48, 58, 48, 48, 58, 48, 48, 46, 48, 48, 48, 32, 45, 45,
+        62, 32, 48, 48, 58, 48, 48, 58, 48, 48, 46, 48, 48, 48, 10
+      };
+  /** The byte offset of the end timecode in {@link #VTT_PREFIX}. */
+  private static final int VTT_PREFIX_END_TIMECODE_OFFSET = 25;
+  /**
+   * The value by which to divide a time in microseconds to convert it to the unit of the last value
+   * in a VTT timecode (milliseconds).
+   */
+  private static final long VTT_TIMECODE_LAST_VALUE_SCALING_FACTOR = 1000;
+  /** The format of a VTT timecode. */
+  private static final String VTT_TIMECODE_FORMAT = "%02d:%02d:%02d.%03d";
+
   /** The length in bytes of a WAVEFORMATEX structure. */
   /** The length in bytes of a WAVEFORMATEX structure. */
   private static final int WAVE_FORMAT_SIZE = 18;
   private static final int WAVE_FORMAT_SIZE = 18;
   /** Format tag indicating a WAVEFORMATEXTENSIBLE structure. */
   /** Format tag indicating a WAVEFORMATEXTENSIBLE structure. */
@@ -1342,7 +1369,9 @@ public class MatroskaExtractor implements Extractor {
       track.trueHdSampleRechunker.sampleMetadata(
       track.trueHdSampleRechunker.sampleMetadata(
           track.output, timeUs, flags, size, offset, track.cryptoData);
           track.output, timeUs, flags, size, offset, track.cryptoData);
     } else {
     } else {
-      if (CODEC_ID_SUBRIP.equals(track.codecId) || CODEC_ID_ASS.equals(track.codecId)) {
+      if (CODEC_ID_SUBRIP.equals(track.codecId)
+          || CODEC_ID_ASS.equals(track.codecId)
+          || CODEC_ID_VTT.equals(track.codecId)) {
         if (blockSampleCount > 1) {
         if (blockSampleCount > 1) {
           Log.w(TAG, "Skipping subtitle sample in laced block.");
           Log.w(TAG, "Skipping subtitle sample in laced block.");
         } else if (blockDurationUs == C.TIME_UNSET) {
         } else if (blockDurationUs == C.TIME_UNSET) {
@@ -1415,6 +1444,9 @@ public class MatroskaExtractor implements Extractor {
     } else if (CODEC_ID_ASS.equals(track.codecId)) {
     } else if (CODEC_ID_ASS.equals(track.codecId)) {
       writeSubtitleSampleData(input, SSA_PREFIX, size);
       writeSubtitleSampleData(input, SSA_PREFIX, size);
       return finishWriteSampleData();
       return finishWriteSampleData();
+    } else if (CODEC_ID_VTT.equals(track.codecId)) {
+      writeSubtitleSampleData(input, VTT_PREFIX, size);
+      return finishWriteSampleData();
     }
     }
 
 
     TrackOutput output = track.output;
     TrackOutput output = track.output;
@@ -1641,7 +1673,8 @@ public class MatroskaExtractor implements Extractor {
    * <p>See documentation on {@link #SSA_DIALOGUE_FORMAT} and {@link #SUBRIP_PREFIX} for why we use
    * <p>See documentation on {@link #SSA_DIALOGUE_FORMAT} and {@link #SUBRIP_PREFIX} for why we use
    * the duration as the end timecode.
    * the duration as the end timecode.
    *
    *
-   * @param codecId The subtitle codec; must be {@link #CODEC_ID_SUBRIP} or {@link #CODEC_ID_ASS}.
+   * @param codecId The subtitle codec; must be {@link #CODEC_ID_SUBRIP}, {@link #CODEC_ID_ASS} or
+   *     {@link #CODEC_ID_VTT}.
    * @param durationUs The duration of the sample, in microseconds.
    * @param durationUs The duration of the sample, in microseconds.
    * @param subtitleData The subtitle sample in which to overwrite the end timecode (output
    * @param subtitleData The subtitle sample in which to overwrite the end timecode (output
    *     parameter).
    *     parameter).
@@ -1662,6 +1695,12 @@ public class MatroskaExtractor implements Extractor {
                 durationUs, SSA_TIMECODE_FORMAT, SSA_TIMECODE_LAST_VALUE_SCALING_FACTOR);
                 durationUs, SSA_TIMECODE_FORMAT, SSA_TIMECODE_LAST_VALUE_SCALING_FACTOR);
         endTimecodeOffset = SSA_PREFIX_END_TIMECODE_OFFSET;
         endTimecodeOffset = SSA_PREFIX_END_TIMECODE_OFFSET;
         break;
         break;
+      case CODEC_ID_VTT:
+        endTimecode =
+            formatSubtitleTimecode(
+                durationUs, VTT_TIMECODE_FORMAT, VTT_TIMECODE_LAST_VALUE_SCALING_FACTOR);
+        endTimecodeOffset = VTT_PREFIX_END_TIMECODE_OFFSET;
+        break;
       default:
       default:
         throw new IllegalArgumentException();
         throw new IllegalArgumentException();
     }
     }
@@ -1830,6 +1869,7 @@ public class MatroskaExtractor implements Extractor {
       case CODEC_ID_PCM_FLOAT:
       case CODEC_ID_PCM_FLOAT:
       case CODEC_ID_SUBRIP:
       case CODEC_ID_SUBRIP:
       case CODEC_ID_ASS:
       case CODEC_ID_ASS:
+      case CODEC_ID_VTT:
       case CODEC_ID_VOBSUB:
       case CODEC_ID_VOBSUB:
       case CODEC_ID_PGS:
       case CODEC_ID_PGS:
       case CODEC_ID_DVBSUB:
       case CODEC_ID_DVBSUB:
@@ -2157,6 +2197,9 @@ public class MatroskaExtractor implements Extractor {
           mimeType = MimeTypes.TEXT_SSA;
           mimeType = MimeTypes.TEXT_SSA;
           initializationData = ImmutableList.of(SSA_DIALOGUE_FORMAT, getCodecPrivate(codecId));
           initializationData = ImmutableList.of(SSA_DIALOGUE_FORMAT, getCodecPrivate(codecId));
           break;
           break;
+        case CODEC_ID_VTT:
+          mimeType = MimeTypes.TEXT_VTT;
+          break;
         case CODEC_ID_VOBSUB:
         case CODEC_ID_VOBSUB:
           mimeType = MimeTypes.APPLICATION_VOBSUB;
           mimeType = MimeTypes.APPLICATION_VOBSUB;
           initializationData = ImmutableList.of(getCodecPrivate(codecId));
           initializationData = ImmutableList.of(getCodecPrivate(codecId));
@@ -2245,6 +2288,7 @@ public class MatroskaExtractor implements Extractor {
             .setColorInfo(colorInfo);
             .setColorInfo(colorInfo);
       } else if (MimeTypes.APPLICATION_SUBRIP.equals(mimeType)
       } else if (MimeTypes.APPLICATION_SUBRIP.equals(mimeType)
           || MimeTypes.TEXT_SSA.equals(mimeType)
           || MimeTypes.TEXT_SSA.equals(mimeType)
+          || MimeTypes.TEXT_VTT.equals(mimeType)
           || MimeTypes.APPLICATION_VOBSUB.equals(mimeType)
           || MimeTypes.APPLICATION_VOBSUB.equals(mimeType)
           || MimeTypes.APPLICATION_PGS.equals(mimeType)
           || MimeTypes.APPLICATION_PGS.equals(mimeType)
           || MimeTypes.APPLICATION_DVBSUBS.equals(mimeType)) {
           || MimeTypes.APPLICATION_DVBSUBS.equals(mimeType)) {

library/extractor/src/test/java/com/google/android/exoplayer2/extractor/mkv/MatroskaExtractorTest.java

@@ -68,6 +68,20 @@ public final class MatroskaExtractorTest {
   }
   }
 
 
   @Test
   @Test
+  public void mkvSample_withVttSubtitles() throws Exception {
+    ExtractorAsserts.assertBehavior(
+        MatroskaExtractor::new, "media/mkv/sample_with_vtt_subtitles.mkv", simulationConfig);
+  }
+
+  @Test
+  public void mkvSample_withNullTerminatedVttSubtitles() throws Exception {
+    ExtractorAsserts.assertBehavior(
+        MatroskaExtractor::new,
+        "media/mkv/sample_with_null_terminated_vtt_subtitles.mkv",
+        simulationConfig);
+  }
+
+  @Test
   public void mkvSample_withVorbisAudio() throws Exception {
   public void mkvSample_withVorbisAudio() throws Exception {
     ExtractorAsserts.assertBehavior(
     ExtractorAsserts.assertBehavior(
         MatroskaExtractor::new, "media/mkv/sample_with_vorbis_audio.mkv", simulationConfig);
         MatroskaExtractor::new, "media/mkv/sample_with_vorbis_audio.mkv", simulationConfig);

testdata/src/test/assets/extractordumps/mkv/sample_with_null_terminated_vtt_subtitles.mkv.0.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 55
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 55, hash F96B22E6
+tracksEnded = true

testdata/src/test/assets/extractordumps/mkv/sample_with_null_terminated_vtt_subtitles.mkv.1.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 55
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 55, hash F96B22E6
+tracksEnded = true

testdata/src/test/assets/extractordumps/mkv/sample_with_null_terminated_vtt_subtitles.mkv.2.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 55
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 55, hash F96B22E6
+tracksEnded = true

testdata/src/test/assets/extractordumps/mkv/sample_with_null_terminated_vtt_subtitles.mkv.3.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 55
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 55, hash F96B22E6
+tracksEnded = true

testdata/src/test/assets/extractordumps/mkv/sample_with_null_terminated_vtt_subtitles.mkv.unknown_length.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 55
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 55, hash F96B22E6
+tracksEnded = true

testdata/src/test/assets/extractordumps/mkv/sample_with_vtt_subtitles.mkv.0.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 65
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 65, hash 3EC9965C
+tracksEnded = true

testdata/src/test/assets/extractordumps/mkv/sample_with_vtt_subtitles.mkv.1.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 65
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 65, hash 3EC9965C
+tracksEnded = true

testdata/src/test/assets/extractordumps/mkv/sample_with_vtt_subtitles.mkv.2.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 65
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 65, hash 3EC9965C
+tracksEnded = true

testdata/src/test/assets/extractordumps/mkv/sample_with_vtt_subtitles.mkv.3.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 65
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 65, hash 3EC9965C
+tracksEnded = true

testdata/src/test/assets/extractordumps/mkv/sample_with_vtt_subtitles.mkv.unknown_length.dump

+seekMap:
+  isSeekable = true
+  duration = 1234000
+  getPosition(0) = [[timeUs=0, position=5661]]
+  getPosition(1) = [[timeUs=0, position=5661]]
+  getPosition(617000) = [[timeUs=0, position=5661]]
+  getPosition(1234000) = [[timeUs=0, position=5661]]
+numberOfTracks = 3
+track 1:
+  total output bytes = 89502
+  sample count = 30
+  format 0:
+    id = 1
+    sampleMimeType = video/avc
+    codecs = avc1.640034
+    width = 1080
+    height = 720
+    selectionFlags = 1
+    language = und
+    initializationData:
+      data = length 30, hash F6F3D010
+      data = length 10, hash 7A0D0F2B
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 36477, hash F0F36CFE
+  sample 1:
+    time = 67000
+    flags = 0
+    data = length 5341, hash 40B85E2
+  sample 2:
+    time = 33000
+    flags = 0
+    data = length 596, hash 357B4D92
+  sample 3:
+    time = 200000
+    flags = 0
+    data = length 7704, hash A39EDA06
+  sample 4:
+    time = 133000
+    flags = 0
+    data = length 989, hash 2813C72D
+  sample 5:
+    time = 100000
+    flags = 0
+    data = length 721, hash C50D1C73
+  sample 6:
+    time = 167000
+    flags = 0
+    data = length 519, hash 65FE1911
+  sample 7:
+    time = 333000
+    flags = 0
+    data = length 6160, hash E1CAC0EC
+  sample 8:
+    time = 267000
+    flags = 0
+    data = length 953, hash 7160C661
+  sample 9:
+    time = 233000
+    flags = 0
+    data = length 620, hash 7A7AE07C
+  sample 10:
+    time = 300000
+    flags = 0
+    data = length 405, hash 5CC7F4E7
+  sample 11:
+    time = 433000
+    flags = 0
+    data = length 4852, hash 9DB6979D
+  sample 12:
+    time = 400000
+    flags = 0
+    data = length 547, hash E31A6979
+  sample 13:
+    time = 367000
+    flags = 0
+    data = length 570, hash FEC40D00
+  sample 14:
+    time = 567000
+    flags = 0
+    data = length 5525, hash 7C478F7E
+  sample 15:
+    time = 500000
+    flags = 0
+    data = length 1082, hash DA07059A
+  sample 16:
+    time = 467000
+    flags = 0
+    data = length 807, hash 93478E6B
+  sample 17:
+    time = 533000
+    flags = 0
+    data = length 744, hash 9A8E6026
+  sample 18:
+    time = 700000
+    flags = 0
+    data = length 4732, hash C73B23C0
+  sample 19:
+    time = 633000
+    flags = 0
+    data = length 1004, hash 8A19A228
+  sample 20:
+    time = 600000
+    flags = 0
+    data = length 794, hash 8126022C
+  sample 21:
+    time = 667000
+    flags = 0
+    data = length 645, hash F08300E5
+  sample 22:
+    time = 833000
+    flags = 0
+    data = length 2684, hash 727FE378
+  sample 23:
+    time = 767000
+    flags = 0
+    data = length 787, hash 419A7821
+  sample 24:
+    time = 733000
+    flags = 0
+    data = length 649, hash 5C159346
+  sample 25:
+    time = 800000
+    flags = 0
+    data = length 509, hash F912D655
+  sample 26:
+    time = 967000
+    flags = 0
+    data = length 1226, hash 29815C21
+  sample 27:
+    time = 900000
+    flags = 0
+    data = length 898, hash D997AD0A
+  sample 28:
+    time = 867000
+    flags = 0
+    data = length 476, hash A0423645
+  sample 29:
+    time = 933000
+    flags = 0
+    data = length 486, hash DDF32CBB
+track 2:
+  total output bytes = 12120
+  sample count = 29
+  format 0:
+    id = 2
+    sampleMimeType = audio/ac3
+    channelCount = 1
+    sampleRate = 44100
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 62000
+    flags = 1
+    data = length 416, hash 211F2286
+  sample 1:
+    time = 96829
+    flags = 1
+    data = length 418, hash 77425A86
+  sample 2:
+    time = 131659
+    flags = 1
+    data = length 418, hash A0FE5CA1
+  sample 3:
+    time = 166489
+    flags = 1
+    data = length 418, hash 2309B066
+  sample 4:
+    time = 201319
+    flags = 1
+    data = length 418, hash 928A653B
+  sample 5:
+    time = 236149
+    flags = 1
+    data = length 418, hash 3422F0CB
+  sample 6:
+    time = 270979
+    flags = 1
+    data = length 418, hash EFF43D5B
+  sample 7:
+    time = 305809
+    flags = 1
+    data = length 418, hash FC8093C7
+  sample 8:
+    time = 341000
+    flags = 1
+    data = length 418, hash CCC08A16
+  sample 9:
+    time = 375829
+    flags = 1
+    data = length 418, hash 2A6EE863
+  sample 10:
+    time = 410659
+    flags = 1
+    data = length 418, hash D69A9251
+  sample 11:
+    time = 445489
+    flags = 1
+    data = length 418, hash BCFB758D
+  sample 12:
+    time = 480319
+    flags = 1
+    data = length 418, hash 11B66799
+  sample 13:
+    time = 515149
+    flags = 1
+    data = length 418, hash C824D392
+  sample 14:
+    time = 549979
+    flags = 1
+    data = length 418, hash C167D872
+  sample 15:
+    time = 584809
+    flags = 1
+    data = length 418, hash 4221C855
+  sample 16:
+    time = 620000
+    flags = 1
+    data = length 418, hash 4D4FF934
+  sample 17:
+    time = 654829
+    flags = 1
+    data = length 418, hash 984AA025
+  sample 18:
+    time = 689659
+    flags = 1
+    data = length 418, hash BB788B46
+  sample 19:
+    time = 724489
+    flags = 1
+    data = length 418, hash 9EFBFD97
+  sample 20:
+    time = 759319
+    flags = 1
+    data = length 418, hash DF1A460C
+  sample 21:
+    time = 794149
+    flags = 1
+    data = length 418, hash 2BDB56A
+  sample 22:
+    time = 828979
+    flags = 1
+    data = length 418, hash CA230060
+  sample 23:
+    time = 863809
+    flags = 1
+    data = length 418, hash D2F19F41
+  sample 24:
+    time = 898000
+    flags = 1
+    data = length 418, hash AF392D79
+  sample 25:
+    time = 932829
+    flags = 1
+    data = length 418, hash C5D7F2A3
+  sample 26:
+    time = 967659
+    flags = 1
+    data = length 418, hash 733A35AE
+  sample 27:
+    time = 1002489
+    flags = 1
+    data = length 418, hash DE46E5D3
+  sample 28:
+    time = 1037319
+    flags = 1
+    data = length 418, hash 56AB8D37
+track 3:
+  total output bytes = 65
+  sample count = 1
+  format 0:
+    id = 3
+    sampleMimeType = text/vtt
+    selectionFlags = 1
+    language = und
+  sample 0:
+    time = 0
+    flags = 1
+    data = length 65, hash 3EC9965C
+tracksEnded = true

testdata/src/test/assets/playbackdumps/mkv/sample_with_null_terminated_vtt_subtitles.mkv.dump

+MediaCodecAdapter (exotest.audio.ac3):
+  buffers.length = 30
+  buffers[0] = length 416, hash 211F2286
+  buffers[1] = length 418, hash 77425A86
+  buffers[2] = length 418, hash A0FE5CA1
+  buffers[3] = length 418, hash 2309B066
+  buffers[4] = length 418, hash 928A653B
+  buffers[5] = length 418, hash 3422F0CB
+  buffers[6] = length 418, hash EFF43D5B
+  buffers[7] = length 418, hash FC8093C7
+  buffers[8] = length 418, hash CCC08A16
+  buffers[9] = length 418, hash 2A6EE863
+  buffers[10] = length 418, hash D69A9251
+  buffers[11] = length 418, hash BCFB758D
+  buffers[12] = length 418, hash 11B66799
+  buffers[13] = length 418, hash C824D392
+  buffers[14] = length 418, hash C167D872
+  buffers[15] = length 418, hash 4221C855
+  buffers[16] = length 418, hash 4D4FF934
+  buffers[17] = length 418, hash 984AA025
+  buffers[18] = length 418, hash BB788B46
+  buffers[19] = length 418, hash 9EFBFD97
+  buffers[20] = length 418, hash DF1A460C
+  buffers[21] = length 418, hash 2BDB56A
+  buffers[22] = length 418, hash CA230060
+  buffers[23] = length 418, hash D2F19F41
+  buffers[24] = length 418, hash AF392D79
+  buffers[25] = length 418, hash C5D7F2A3
+  buffers[26] = length 418, hash 733A35AE
+  buffers[27] = length 418, hash DE46E5D3
+  buffers[28] = length 418, hash 56AB8D37
+  buffers[29] = length 0, hash 1
+MediaCodecAdapter (exotest.video.avc):
+  buffers.length = 31
+  buffers[0] = length 36477, hash F0F36CFE
+  buffers[1] = length 5341, hash 40B85E2
+  buffers[2] = length 596, hash 357B4D92
+  buffers[3] = length 7704, hash A39EDA06
+  buffers[4] = length 989, hash 2813C72D
+  buffers[5] = length 721, hash C50D1C73
+  buffers[6] = length 519, hash 65FE1911
+  buffers[7] = length 6160, hash E1CAC0EC
+  buffers[8] = length 953, hash 7160C661
+  buffers[9] = length 620, hash 7A7AE07C
+  buffers[10] = length 405, hash 5CC7F4E7
+  buffers[11] = length 4852, hash 9DB6979D
+  buffers[12] = length 547, hash E31A6979
+  buffers[13] = length 570, hash FEC40D00
+  buffers[14] = length 5525, hash 7C478F7E
+  buffers[15] = length 1082, hash DA07059A
+  buffers[16] = length 807, hash 93478E6B
+  buffers[17] = length 744, hash 9A8E6026
+  buffers[18] = length 4732, hash C73B23C0
+  buffers[19] = length 1004, hash 8A19A228
+  buffers[20] = length 794, hash 8126022C
+  buffers[21] = length 645, hash F08300E5
+  buffers[22] = length 2684, hash 727FE378
+  buffers[23] = length 787, hash 419A7821
+  buffers[24] = length 649, hash 5C159346
+  buffers[25] = length 509, hash F912D655
+  buffers[26] = length 1226, hash 29815C21
+  buffers[27] = length 898, hash D997AD0A
+  buffers[28] = length 476, hash A0423645
+  buffers[29] = length 486, hash DDF32CBB
+  buffers[30] = length 0, hash 1

testdata/src/test/assets/playbackdumps/mkv/sample_with_vtt_subtitles.mkv.dump

+MediaCodecAdapter (exotest.audio.ac3):
+  buffers.length = 30
+  buffers[0] = length 416, hash 211F2286
+  buffers[1] = length 418, hash 77425A86
+  buffers[2] = length 418, hash A0FE5CA1
+  buffers[3] = length 418, hash 2309B066
+  buffers[4] = length 418, hash 928A653B
+  buffers[5] = length 418, hash 3422F0CB
+  buffers[6] = length 418, hash EFF43D5B
+  buffers[7] = length 418, hash FC8093C7
+  buffers[8] = length 418, hash CCC08A16
+  buffers[9] = length 418, hash 2A6EE863
+  buffers[10] = length 418, hash D69A9251
+  buffers[11] = length 418, hash BCFB758D
+  buffers[12] = length 418, hash 11B66799
+  buffers[13] = length 418, hash C824D392
+  buffers[14] = length 418, hash C167D872
+  buffers[15] = length 418, hash 4221C855
+  buffers[16] = length 418, hash 4D4FF934
+  buffers[17] = length 418, hash 984AA025
+  buffers[18] = length 418, hash BB788B46
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+  buffers[27] = length 418, hash DE46E5D3
+  buffers[28] = length 418, hash 56AB8D37
+  buffers[29] = length 0, hash 1
+MediaCodecAdapter (exotest.video.avc):
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+  buffers[1] = length 5341, hash 40B85E2
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+  buffers[28] = length 476, hash A0423645
+  buffers[29] = length 486, hash DDF32CBB
+  buffers[30] = length 0, hash 1