Cast: Provide more meaningful stats.

chrome/renderer/media/cast_session_delegate.cc

Index: chrome/renderer/media/cast_session_delegate.cc
diff --git a/chrome/renderer/media/cast_session_delegate.cc b/chrome/renderer/media/cast_session_delegate.cc
index 919324966b54de06f43a3120c02fc1665b98d290..cc5060fc9da5bbdd3c47da4f1789fffe6ff7b83b 100644
--- a/chrome/renderer/media/cast_session_delegate.cc
+++ b/chrome/renderer/media/cast_session_delegate.cc
@@ -16,8 +16,8 @@
 #include "media/cast/logging/encoding_event_subscriber.h"
 #include "media/cast/logging/log_serializer.h"
 #include "media/cast/logging/logging_defines.h"
+#include "media/cast/logging/receiver_time_offset_estimator_impl.h"
 #include "media/cast/logging/stats_event_subscriber.h"
-#include "media/cast/logging/stats_util.h"
 #include "media/cast/transport/cast_transport_config.h"
 #include "media/cast/transport/cast_transport_sender.h"
 
@@ -53,6 +53,10 @@ CastSessionDelegate::~CastSessionDelegate() {
   DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
   if (cast_environment_.get()) {
+    if (receiver_offset_estimator_.get()) {
+      cast_environment_->Logging()->RemoveRawEventSubscriber(
+          receiver_offset_estimator_.get());
+    }
     if (audio_event_subscriber_.get()) {
       cast_environment_->Logging()->RemoveRawEventSubscriber(
           audio_event_subscriber_.get());
@@ -146,6 +150,12 @@ void CastSessionDelegate::ToggleLogging(bool is_audio, bool enable) {
   if (!cast_environment_.get())
     return;
   if (enable) {
+    if (!receiver_offset_estimator_.get()) {

[miu, 2014/04/15 21:29:43]

There's a huge amount of copy-and-paste going throughout CastSessionDelegate,
and especially in this method.  Each EventSubscriber is basically going through
the same steps.

Suggestion: Rather than five separate scoped_ptr<> members, can you just keep a
list<linked_ptr<Subscriber>>?  Then your code becomes:

if (enable) {
  DCHECK(event_subscribers_.empty());
  event_subscribers_.push_back(new FooSubscriber(...));
  event_subscribers_.push_back(new BarSubscriber(...));
  event_subscribers_.push_back(new BazSubscriber(...));
  event_subscribers_.push_back(new GlarfSubscriber(...));
  for (it = event_subscribers_.begin(); it != end(); ++it)
    cast_environment_->Logging()->AddRawEventSubscriber(it->get());
} else {
  for (it = event_subscribers_.begin(); it != end(); ++it)
    cast_environment_->Logging()-RemovedRawEventSubscriber(it->get());
  event_subscribers_.clear();
}

[imcheng, 2014/04/17 19:19:06]

Per offline discussion I am defining a new struct to bundle the subscribers
together. But since we support switching on/off logging by stream, we have 2
sub-bundles. I am going to use a map from bool to sub-bundles to reduce some
code duplication (as opposed to "if(is_audio) ... else ..."). If we do support
more than 2 streams later, it will not be hard to change the key from bool to
int (stream id).


On 2014/04/15 21:29:43, miu wrote:

+      receiver_offset_estimator_.reset(
+          new media::cast::ReceiverTimeOffsetEstimatorImpl);
+      cast_environment_->Logging()->AddRawEventSubscriber(
+          receiver_offset_estimator_.get());
+    }
     if (is_audio) {
       if (!audio_event_subscriber_.get()) {
         audio_event_subscriber_.reset(new media::cast::EncodingEventSubscriber(
@@ -154,8 +164,10 @@ void CastSessionDelegate::ToggleLogging(bool is_audio, bool enable) {
             audio_event_subscriber_.get());
       }
       if (!audio_stats_subscriber_.get()) {
-        audio_stats_subscriber_.reset(
-            new media::cast::StatsEventSubscriber(media::cast::AUDIO_EVENT));
+        audio_stats_subscriber_.reset(new media::cast::StatsEventSubscriber(
+            media::cast::AUDIO_EVENT,
+            cast_environment_->Clock(),
+            receiver_offset_estimator_.get()));
         cast_environment_->Logging()->AddRawEventSubscriber(
             audio_stats_subscriber_.get());
       }
@@ -167,13 +179,21 @@ void CastSessionDelegate::ToggleLogging(bool is_audio, bool enable) {
             video_event_subscriber_.get());
       }
       if (!video_stats_subscriber_.get()) {
-        video_stats_subscriber_.reset(
-            new media::cast::StatsEventSubscriber(media::cast::VIDEO_EVENT));
+        video_stats_subscriber_.reset(new media::cast::StatsEventSubscriber(
+            media::cast::VIDEO_EVENT,
+            cast_environment_->Clock(),
+            receiver_offset_estimator_.get()));
         cast_environment_->Logging()->AddRawEventSubscriber(
             video_stats_subscriber_.get());
       }
     }
   } else {
+    if (receiver_offset_estimator_.get()) {
+      cast_environment_->Logging()->RemoveRawEventSubscriber(
+          receiver_offset_estimator_.get());
+      receiver_offset_estimator_.reset();
+    }
+
     if (is_audio) {
       if (audio_event_subscriber_.get()) {
         cast_environment_->Logging()->RemoveRawEventSubscriber(
@@ -250,15 +270,9 @@ void CastSessionDelegate::GetStatsAndReset(bool is_audio,
     return;
   }
 
-  media::cast::FrameStatsMap frame_stats;
-  subscriber->GetFrameStats(&frame_stats);
-  media::cast::PacketStatsMap packet_stats;
-  subscriber->GetPacketStats(&packet_stats);
+  scoped_ptr<base::DictionaryValue> stats = subscriber->GetStats();
   subscriber->Reset();
 
-  scoped_ptr<base::DictionaryValue> stats = media::cast::ConvertStats(
-      frame_stats, packet_stats);
-
   callback.Run(stats.Pass());
 }