Add support for accepting MPEG2 AAC-LC bitstreams.

media/mp4/mp4_stream_parser.cc

Index: media/mp4/mp4_stream_parser.cc
diff --git a/media/mp4/mp4_stream_parser.cc b/media/mp4/mp4_stream_parser.cc
index 38333fb64761e0741c3f77fa952d988ff983ede6..f7a00da3a7c2b3146db487a4c03f7a73c3807aee 100644
--- a/media/mp4/mp4_stream_parser.cc
+++ b/media/mp4/mp4_stream_parser.cc
@@ -23,7 +23,8 @@ namespace mp4 {
 // TODO(xhwang): Figure out the init data type appropriately once it's spec'ed.
 static const char kMp4InitDataType[] = "video/mp4";
 
-MP4StreamParser::MP4StreamParser(bool has_sbr)
+MP4StreamParser::MP4StreamParser(const std::set<int>& audio_object_types,
+                                 bool has_sbr)
     : state_(kWaitingForInit),
       moof_head_(0),
       mdat_tail_(0),
@@ -31,6 +32,7 @@ MP4StreamParser::MP4StreamParser(bool has_sbr)
       has_video_(false),
       audio_track_id_(0),
       video_track_id_(0),
+      audio_object_types_(audio_object_types),
       has_sbr_(has_sbr) {
 }
 
@@ -200,11 +202,20 @@ bool MP4StreamParser::ParseMoov(BoxReader* reader) {
                            << std::hex << entry.format << " in stsd box.";
         return false;
       }
-      // Check if it is MPEG4 AAC defined in ISO 14496 Part 3.
-      if (entry.esds.object_type != kISO_14496_3) {
+
+      int audio_type = entry.esds.object_type;
+      if (audio_object_types_.find(audio_type) == audio_object_types_.end()) {
+        MEDIA_LOG(log_cb_) << "audio object type 0x" << std::hex << audio_type
+                           << " does not match what is specified in the"
+                           << " mimetype.";
+        return false;
+      }
+
+      // Check if it is MPEG4 AAC defined in ISO 14496 Part 3 or
+      // supported MPEG2 AAC varients.
+      if (audio_type != kISO_14496_3 && audio_type != kISO_13818_7_AAC_LC) {

[scherkus (not reviewing), 2013/01/08 23:51:08]

worth switch+case-ifying against future changes to mp4::ObjectType?

[acolwell GONE FROM CHROMIUM, 2013/01/16 17:35:09]

Unfortunately since audio_type comes directly from the file, the switch would
have to include a default: case, which would cancel out the benefit of the
switch.

         MEDIA_LOG(log_cb_) << "Unsupported audio object type 0x" << std::hex
-                           << static_cast<int>(entry.esds.object_type)
-                           << " in esds.";
+                           << audio_type << " in esds.";
         return false;
       }