Merge "Ignore audio sync sample list" am: f9ac0e84e2 am: 34dec945e6
am: ee3eb46566

Change-Id: I97d4f6c2d2eb3dac74626cfd9edc1831b38cee37
diff --git a/media/extractors/mp4/MPEG4Extractor.cpp b/media/extractors/mp4/MPEG4Extractor.cpp
index c776c51..4298b57 100755
--- a/media/extractors/mp4/MPEG4Extractor.cpp
+++ b/media/extractors/mp4/MPEG4Extractor.cpp
@@ -142,6 +142,7 @@
     uint8_t *mSrcBuffer;
 
     bool mIsHeif;
+    bool mIsAudio;
     sp<ItemTable> mItemTable;
 
     // Start offset from composition time to presentation time.
@@ -4530,6 +4531,7 @@
     }
 
     mIsPcm = !strcasecmp(mime, MEDIA_MIMETYPE_AUDIO_RAW);
+    mIsAudio = !strncasecmp(mime, "audio/", 6);
 
     if (mIsPcm) {
         int32_t numChannels = 0;
@@ -5416,8 +5418,11 @@
                 findFlags = SampleTable::kFlagBefore;
             }
 
-            uint32_t syncSampleIndex;
-            if (err == OK) {
+            uint32_t syncSampleIndex = sampleIndex;
+            // assume every audio sample is a sync sample. This works around
+            // seek issues with files that were incorrectly written with an
+            // empty or single-sample stss block for the audio track
+            if (err == OK && !mIsAudio) {
                 err = mSampleTable->findSyncSampleNear(
                         sampleIndex, &syncSampleIndex, findFlags);
             }