[EME] Add support for sbgp and sgpd boxes occuring in the sampletable

3 files changed, 48 insertions, 13 deletions

diff --git a/media/libstagefright/binding/Index.cpp b/media/libstagefright/binding/Index.cpp
index a3a3f9847..eb039b5d6 100644
--- a/media/libstagefright/binding/Index.cpp
+++ b/media/libstagefright/binding/Index.cpp
@@ -181,9 +181,16 @@ CencSampleEncryptionInfoEntry* SampleIterator::GetSampleEncryptionEntry()
   Moof* currentMoof = &moofs[mCurrentMoof];
   SampleToGroupEntry* sampleToGroupEntry = nullptr;
 
+  // Default to using the sample to group entries for the fragment, otherwise
+  // fall back to the sample to group entries for the track.
+  nsTArray<SampleToGroupEntry>* sampleToGroupEntries =
+    currentMoof->mFragmentSampleToGroupEntries.Length() != 0
+    ? &currentMoof->mFragmentSampleToGroupEntries
+    : &mIndex->mMoofParser->mTrackSampleToGroupEntries;
+
   uint32_t seen = 0;
 
-  for (SampleToGroupEntry& entry : currentMoof->mSampleToGroupEntries) {
+  for (SampleToGroupEntry& entry : *sampleToGroupEntries) {
     if (seen + entry.mSampleCount > mCurrentSample) {
       sampleToGroupEntry = &entry;
       break;
@@ -200,20 +207,31 @@ CencSampleEncryptionInfoEntry* SampleIterator::GetSampleEncryptionEntry()
   // 1, with the value 1 in the top 16 bits, to reference fragment-local
   // SampleGroupDescription Box.
 
+  // According to the spec, ISO-14496-12, the sum of the sample counts in this
+  // box should be equal to the total number of samples, and, if less, the
+  // reader should behave as if an extra SampleToGroupEntry existed, with
+  // groupDescriptionIndex 0.
+
   if (!sampleToGroupEntry || sampleToGroupEntry->mGroupDescriptionIndex == 0) {
     return nullptr;
   }
 
-  uint32_t group_index = sampleToGroupEntry->mGroupDescriptionIndex;
+  nsTArray<CencSampleEncryptionInfoEntry>* entries =
+                      &mIndex->mMoofParser->mTrackSampleEncryptionInfoEntries;
+
+  uint32_t groupIndex = sampleToGroupEntry->mGroupDescriptionIndex;
 
-  if (group_index > SampleToGroupEntry::kFragmentGroupDescriptionIndexBase) {
-    group_index -= SampleToGroupEntry::kFragmentGroupDescriptionIndexBase;
+  // If the first bit is set to a one, then we should use the sample group
+  // descriptions from the fragment.
+  if (groupIndex > SampleToGroupEntry::kFragmentGroupDescriptionIndexBase) {
+    groupIndex -= SampleToGroupEntry::kFragmentGroupDescriptionIndexBase;
+    entries = &currentMoof->mFragmentSampleEncryptionInfoEntries;
   }
 
-  // The group_index is one indexed
-  return group_index > currentMoof->mSampleEncryptionInfoEntries.Length()
+  // The group_index is one based.
+  return groupIndex > entries->Length()
          ? nullptr
-         : &currentMoof->mSampleEncryptionInfoEntries.ElementAt(group_index - 1);
+         : &entries->ElementAt(groupIndex - 1);
 }
 
 Sample* SampleIterator::Get()
diff --git a/media/libstagefright/binding/MoofParser.cpp b/media/libstagefright/binding/MoofParser.cpp
index 970bc2325..4abad747b 100644
--- a/media/libstagefright/binding/MoofParser.cpp
+++ b/media/libstagefright/binding/MoofParser.cpp
@@ -332,6 +332,18 @@ MoofParser::ParseStbl(Box& aBox)
   for (Box box = aBox.FirstChild(); box.IsAvailable(); box = box.Next()) {
     if (box.IsType("stsd")) {
       ParseStsd(box);
+      } else if (box.IsType("sgpd")) {
+      Sgpd sgpd(box);
+      if (sgpd.IsValid() && sgpd.mGroupingType == "seig") {
+        mTrackSampleEncryptionInfoEntries.Clear();
+        mTrackSampleEncryptionInfoEntries.AppendElements(sgpd.mEntries);
+      }
+    } else if (box.IsType("sbgp")) {
+      Sbgp sbgp(box);
+      if (sbgp.IsValid() && sbgp.mGroupingType == "seig") {
+        mTrackSampleToGroupEntries.Clear();
+        mTrackSampleToGroupEntries.AppendElements(sbgp.mEntries);
+      }
     }
   }
 }
@@ -497,6 +509,7 @@ Moof::ParseTraf(Box& aBox, Trex& aTrex, Mvhd& aMvhd, Mdhd& aMdhd, Edts& aEdts, S
   MOZ_ASSERT(aDecodeTime);
   Tfhd tfhd(aTrex);
   Tfdt tfdt;
+
   for (Box box = aBox.FirstChild(); box.IsAvailable(); box = box.Next()) {
     if (box.IsType("tfhd")) {
       tfhd = Tfhd(box, aTrex);
@@ -506,14 +519,14 @@ Moof::ParseTraf(Box& aBox, Trex& aTrex, Mvhd& aMvhd, Mdhd& aMdhd, Edts& aEdts, S
       } else if (box.IsType("sgpd")) {
         Sgpd sgpd(box);
         if (sgpd.IsValid() && sgpd.mGroupingType == "seig") {
-          mSampleEncryptionInfoEntries.Clear();
-          mSampleEncryptionInfoEntries.AppendElements(sgpd.mEntries);
+          mFragmentSampleEncryptionInfoEntries.Clear();
+          mFragmentSampleEncryptionInfoEntries.AppendElements(sgpd.mEntries);
         }
       } else if (box.IsType("sbgp")) {
         Sbgp sbgp(box);
         if (sbgp.IsValid() && sbgp.mGroupingType == "seig") {
-          mSampleToGroupEntries.Clear();
-          mSampleToGroupEntries.AppendElements(sbgp.mEntries);
+          mFragmentSampleToGroupEntries.Clear();
+          mFragmentSampleToGroupEntries.AppendElements(sbgp.mEntries);
         }
       } else if (box.IsType("saiz")) {
         mSaizs.AppendElement(Saiz(box, aSinf.mDefaultEncryptionType));
diff --git a/media/libstagefright/binding/include/mp4_demuxer/MoofParser.h b/media/libstagefright/binding/include/mp4_demuxer/MoofParser.h
index 47bd27287..bb895555c 100644
--- a/media/libstagefright/binding/include/mp4_demuxer/MoofParser.h
+++ b/media/libstagefright/binding/include/mp4_demuxer/MoofParser.h
@@ -230,8 +230,8 @@ public:
   Interval<Microseconds> mTimeRange;
   FallibleTArray<Sample> mIndex;
 
-  nsTArray<CencSampleEncryptionInfoEntry> mSampleEncryptionInfoEntries;
-  nsTArray<SampleToGroupEntry> mSampleToGroupEntries;
+  nsTArray<CencSampleEncryptionInfoEntry> mFragmentSampleEncryptionInfoEntries;
+  nsTArray<SampleToGroupEntry> mFragmentSampleToGroupEntries;
 
   nsTArray<Saiz> mSaizs;
   nsTArray<Saio> mSaios;
@@ -297,6 +297,10 @@ public:
   Tfdt mTfdt;
   Edts mEdts;
   Sinf mSinf;
+
+  nsTArray<CencSampleEncryptionInfoEntry> mTrackSampleEncryptionInfoEntries;
+  nsTArray<SampleToGroupEntry> mTrackSampleToGroupEntries;
+
   nsTArray<Moof>& Moofs() { return mMoofs; }
 private:
   void ScanForMetadata(mozilla::MediaByteRange& aFtyp,