Fix SPS/PPS insertion logic in MP4StreamParser.

media/formats/mp4/mp4_stream_parser.cc

Index: media/formats/mp4/mp4_stream_parser.cc
diff --git a/media/formats/mp4/mp4_stream_parser.cc b/media/formats/mp4/mp4_stream_parser.cc
index 3136e1931d64435d705316d41f0ac79800cd1814..38a4c0ae42bf33eb241be2e47e8a3d7b2de058ce 100644
--- a/media/formats/mp4/mp4_stream_parser.cc
+++ b/media/formats/mp4/mp4_stream_parser.cc
@@ -365,13 +365,13 @@ bool MP4StreamParser::PrepareAVCBuffer(
     // If this is a keyframe, we (re-)inject SPS and PPS headers at the start of
     // a frame. If subsample info is present, we also update the clear byte
     // count for that first subsample.
-    std::vector<uint8> param_sets;
-    RCHECK(AVC::ConvertConfigToAnnexB(avc_config, &param_sets));
-    frame_buf->insert(frame_buf->begin(),
-                      param_sets.begin(), param_sets.end());
+    size_t old_size = frame_buf->size();
+    RCHECK(AVC::InsertParamSetsAnnexB(avc_config, frame_buf));
     if (!subsamples->empty())

[damienv1, 2014/04/23 00:20:47]

Would be nice if InsertParamSetsAnnexB returns the insert position so that some
sanity check can be done for encrypted content:

if (!subsamples->empty() && frame_buf->size() > old_size) {
  DCHECK_LE(insert_position, (*subsamples)[0].clear_bytes);
  ...
}

-      (*subsamples)[0].clear_bytes += param_sets.size();
+      (*subsamples)[0].clear_bytes += frame_buf->size() - old_size;
   }
+
+  DCHECK(AVC::IsValidAnnexB(*frame_buf));
   return true;
 }