media: Opus support for WebM in Media Source

media/webm/webm_cluster_parser.cc

Index: media/webm/webm_cluster_parser.cc
diff --git a/media/webm/webm_cluster_parser.cc b/media/webm/webm_cluster_parser.cc
index 9991d6b4d15a3fec60a407d84e59a1417b50dafc..1778a3ae267dd8bc358181d512c7b331dccc01eb 100644
--- a/media/webm/webm_cluster_parser.cc
+++ b/media/webm/webm_cluster_parser.cc
@@ -64,6 +64,7 @@ WebMClusterParser::WebMClusterParser(
       block_duration_(-1),
       block_add_id_(-1),
       block_additional_data_size_(-1),
+      discard_padding_(-1),
       cluster_timecode_(-1),
       cluster_start_time_(kNoTimestamp()),
       cluster_ended_(false),
@@ -137,6 +138,8 @@ WebMParserClient* WebMClusterParser::OnListStart(int id) {
     block_data_.reset();
     block_data_size_ = -1;
     block_duration_ = -1;
+    discard_padding_ = -1;
+    discard_padding_set_ = false;
   } else if (id == kWebMIdBlockAdditions) {
     block_add_id_ = -1;
     block_additional_data_.reset();
@@ -158,13 +161,16 @@ bool WebMClusterParser::OnListEnd(int id) {
 
   bool result = ParseBlock(false, block_data_.get(), block_data_size_,
                            block_additional_data_.get(),
-                           block_additional_data_size_, block_duration_);
+                           block_additional_data_size_, block_duration_,
+                           discard_padding_);
   block_data_.reset();
   block_data_size_ = -1;
   block_duration_ = -1;
   block_add_id_ = -1;
   block_additional_data_.reset();
   block_additional_data_size_ = -1;
+  discard_padding_ = discard_padding_set_ ? discard_padding_ : 0;

[acolwell GONE FROM CHROMIUM, 2013/09/04 20:08:43]

nit: Sorry if I wasn't clear. I meant to place this in the call to ParseBlock().
I think the code this way will cause discard_padding to be set to -1 for formats
like Vorbis that may have block groups, but don't specify discard_padding.

The alternative is to always set_discard_padding_ = 0 everywhere in this file
that you set it to -1. Then discard_padding_set_ is only used to signal an error
if multiple DiscardPadding elements are encountered.

[vignesh, 2013/09/04 20:27:46]

Done.

+  discard_padding_set_ = false;
   return result;
 }
 
@@ -180,6 +186,12 @@ bool WebMClusterParser::OnUInt(int id, int64 val) {
     case kWebMIdBlockAddID:
       dst = &block_add_id_;
       break;
+    case kWebMIdDiscardPadding:
+      if (discard_padding_set_)
+        return false;
+      discard_padding_set_ = true;
+      discard_padding_ = val;
+      return true;
     default:
       return true;
   }
@@ -191,7 +203,8 @@ bool WebMClusterParser::OnUInt(int id, int64 val) {
 
 bool WebMClusterParser::ParseBlock(bool is_simple_block, const uint8* buf,
                                    int size, const uint8* additional,
-                                   int additional_size, int duration) {
+                                   int additional_size, int duration,
+                                   int64 discard_padding) {
   if (size < 4)
     return false;
 
@@ -219,13 +232,14 @@ bool WebMClusterParser::ParseBlock(bool is_simple_block, const uint8* buf,
   const uint8* frame_data = buf + 4;
   int frame_size = size - (frame_data - buf);
   return OnBlock(is_simple_block, track_num, timecode, duration, flags,
-                 frame_data, frame_size, additional, additional_size);
+                 frame_data, frame_size, additional, additional_size,
+                 discard_padding);
 }
 
 bool WebMClusterParser::OnBinary(int id, const uint8* data, int size) {
   switch (id) {
     case kWebMIdSimpleBlock:
-      return ParseBlock(true, data, size, NULL, -1, -1);
+      return ParseBlock(true, data, size, NULL, -1, -1, -1);
 
     case kWebMIdBlock:
       if (block_data_) {
@@ -270,7 +284,8 @@ bool WebMClusterParser::OnBlock(bool is_simple_block, int track_num,
                                 int  block_duration,
                                 int flags,
                                 const uint8* data, int size,
-                                const uint8* additional, int additional_size) {
+                                const uint8* additional, int additional_size,
+                                int64 discard_padding) {
   DCHECK_GE(size, 0);
   if (cluster_timecode_ == -1) {
     MEDIA_LOG(log_cb_) << "Got a block before cluster timecode.";
@@ -350,6 +365,11 @@ bool WebMClusterParser::OnBlock(bool is_simple_block, int track_num,
         block_duration * timecode_multiplier_));
   }
 
+  if (discard_padding != 0) {
+    buffer->set_discard_padding(base::TimeDelta::FromMicroseconds(
+                                    discard_padding / 1000));
+  }
+
   return track->AddBuffer(buffer);
 }