Avoid throwing an exception for sample default values

Allows playback of content when the default value is not valid, but not used for any samples. Issue: #7207 PiperOrigin-RevId: 306631376
google · May 27, 2020 · 2df9491 · 2df9491
1 parent bdc0db3
commit 2df9491
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diff --git a/RELEASENOTES.md b/RELEASENOTES.md
@@ -1,5 +1,11 @@
 # Release notes #
 
+### Next release ###
+
+*   Avoid throwing an exception while parsing fragmented MP4 default sample
+    values where the most-significant bit is set
+    ([#7207](https://github.com/google/ExoPlayer/issues/7207)).
+
 ### 2.11.4 (2020-04-08) ###
 
 * Add `SimpleExoPlayer.setWakeMode` to allow automatic `WifiLock` and `WakeLock`

diff --git a/...ore/src/main/java/com/google/android/exoplayer2/extractor/mp4/FragmentedMp4Extractor.java b/...ore/src/main/java/com/google/android/exoplayer2/extractor/mp4/FragmentedMp4Extractor.java
@@ -664,9 +664,9 @@ private void onEmsgLeafAtomRead(ParsableByteArray atom) {
   private static Pair<Integer, DefaultSampleValues> parseTrex(ParsableByteArray trex) {
     trex.setPosition(Atom.FULL_HEADER_SIZE);
     int trackId = trex.readInt();
-    int defaultSampleDescriptionIndex = trex.readUnsignedIntToInt() - 1;
-    int defaultSampleDuration = trex.readUnsignedIntToInt();
-    int defaultSampleSize = trex.readUnsignedIntToInt();
+    int defaultSampleDescriptionIndex = trex.readInt() - 1;
+    int defaultSampleDuration = trex.readInt();
+    int defaultSampleSize = trex.readInt();
     int defaultSampleFlags = trex.readInt();
 
     return Pair.create(trackId, new DefaultSampleValues(defaultSampleDescriptionIndex,
@@ -751,8 +751,9 @@ private static void parseTraf(ContainerAtom traf, SparseArray<TrackBundle> track
     }
   }
 
-  private static void parseTruns(ContainerAtom traf, TrackBundle trackBundle, long decodeTime,
-      @Flags int flags) {
+  private static void parseTruns(
+      ContainerAtom traf, TrackBundle trackBundle, long decodeTime, @Flags int flags)
+      throws ParserException {
     int trunCount = 0;
     int totalSampleCount = 0;
     List<LeafAtom> leafChildren = traf.leafChildren;
@@ -871,13 +872,20 @@ private static TrackBundle parseTfhd(
     DefaultSampleValues defaultSampleValues = trackBundle.defaultSampleValues;
     int defaultSampleDescriptionIndex =
         ((atomFlags & 0x02 /* default_sample_description_index_present */) != 0)
-            ? tfhd.readUnsignedIntToInt() - 1 : defaultSampleValues.sampleDescriptionIndex;
-    int defaultSampleDuration = ((atomFlags & 0x08 /* default_sample_duration_present */) != 0)
-        ? tfhd.readUnsignedIntToInt() : defaultSampleValues.duration;
-    int defaultSampleSize = ((atomFlags & 0x10 /* default_sample_size_present */) != 0)
-        ? tfhd.readUnsignedIntToInt() : defaultSampleValues.size;
-    int defaultSampleFlags = ((atomFlags & 0x20 /* default_sample_flags_present */) != 0)
-        ? tfhd.readUnsignedIntToInt() : defaultSampleValues.flags;
+            ? tfhd.readInt() - 1
+            : defaultSampleValues.sampleDescriptionIndex;
+    int defaultSampleDuration =
+        ((atomFlags & 0x08 /* default_sample_duration_present */) != 0)
+            ? tfhd.readInt()
+            : defaultSampleValues.duration;
+    int defaultSampleSize =
+        ((atomFlags & 0x10 /* default_sample_size_present */) != 0)
+            ? tfhd.readInt()
+            : defaultSampleValues.size;
+    int defaultSampleFlags =
+        ((atomFlags & 0x20 /* default_sample_flags_present */) != 0)
+            ? tfhd.readInt()
+            : defaultSampleValues.flags;
     trackBundle.fragment.header = new DefaultSampleValues(defaultSampleDescriptionIndex,
         defaultSampleDuration, defaultSampleSize, defaultSampleFlags);
     return trackBundle;
@@ -910,16 +918,22 @@ private static long parseTfdt(ParsableByteArray tfdt) {
   /**
    * Parses a trun atom (defined in 14496-12).
    *
-   * @param trackBundle The {@link TrackBundle} that contains the {@link TrackFragment} into
-   *     which parsed data should be placed.
+   * @param trackBundle The {@link TrackBundle} that contains the {@link TrackFragment} into which
+   *     parsed data should be placed.
    * @param index Index of the track run in the fragment.
    * @param decodeTime The decode time of the first sample in the fragment run.
    * @param flags Flags to allow any required workaround to be executed.
    * @param trun The trun atom to decode.
    * @return The starting position of samples for the next run.
    */
-  private static int parseTrun(TrackBundle trackBundle, int index, long decodeTime,
-      @Flags int flags, ParsableByteArray trun, int trackRunStart) {
+  private static int parseTrun(
+      TrackBundle trackBundle,
+      int index,
+      long decodeTime,
+      @Flags int flags,
+      ParsableByteArray trun,
+      int trackRunStart)
+      throws ParserException {
     trun.setPosition(Atom.HEADER_SIZE);
     int fullAtom = trun.readInt();
     int atomFlags = Atom.parseFullAtomFlags(fullAtom);
@@ -937,7 +951,7 @@ private static int parseTrun(TrackBundle trackBundle, int index, long decodeTime
     boolean firstSampleFlagsPresent = (atomFlags & 0x04 /* first_sample_flags_present */) != 0;
     int firstSampleFlags = defaultSampleValues.flags;
     if (firstSampleFlagsPresent) {
-      firstSampleFlags = trun.readUnsignedIntToInt();
+      firstSampleFlags = trun.readInt();
     }
 
     boolean sampleDurationsPresent = (atomFlags & 0x100 /* sample_duration_present */) != 0;
@@ -972,9 +986,10 @@ private static int parseTrun(TrackBundle trackBundle, int index, long decodeTime
     long cumulativeTime = index > 0 ? fragment.nextFragmentDecodeTime : decodeTime;
     for (int i = trackRunStart; i < trackRunEnd; i++) {
       // Use trun values if present, otherwise tfhd, otherwise trex.
-      int sampleDuration = sampleDurationsPresent ? trun.readUnsignedIntToInt()
-          : defaultSampleValues.duration;
-      int sampleSize = sampleSizesPresent ? trun.readUnsignedIntToInt() : defaultSampleValues.size;
+      int sampleDuration =
+          checkNonNegative(sampleDurationsPresent ? trun.readInt() : defaultSampleValues.duration);
+      int sampleSize =
+          checkNonNegative(sampleSizesPresent ? trun.readInt() : defaultSampleValues.size);
       int sampleFlags = (i == 0 && firstSampleFlagsPresent) ? firstSampleFlags
           : sampleFlagsPresent ? trun.readInt() : defaultSampleValues.flags;
       if (sampleCompositionTimeOffsetsPresent) {
@@ -1000,6 +1015,13 @@ private static int parseTrun(TrackBundle trackBundle, int index, long decodeTime
     return trackRunEnd;
   }
 
+  private static int checkNonNegative(int value) throws ParserException {
+    if (value < 0) {
+      throw new ParserException("Unexpected negtive value: " + value);
+    }
+    return value;
+  }
+
   private static void parseUuid(ParsableByteArray uuid, TrackFragment out,
       byte[] extendedTypeScratch) throws ParserException {
     uuid.setPosition(Atom.HEADER_SIZE);