Cast: Provide more meaningful stats.

- Instead of giving generic stats for each event type,
  StatsEventSubsriber will now provide more specific stats. It also
  provide new kinds of stats (packet loss %, latency)
- stats_util to convert output of StatsEventSubscriber to a
  base::DictionaryValue is moved into the subscriber implementation.
- Introduced ReceiverTimeOffsetEstimator to estimate receiver offset
  based on raw events received. It is used by StatsEventSubscriber to
  determine stats such as latency. The estimator itself is implemented
  as a RawEventSubscriber and is shared between the audio and video
  StatsEventSubscriber objects.
- Move stats related structs from logging_defines.{cc,h} into
  stats_event_subscriber.{cc,h}
BUG=353019

Review URL: https://codereview.chromium.org/236123003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@266574 0039d316-1c4b-4281-b951-d872f2087c98

18 files changed, 1614 insertions, 249 deletions

diff --git a/media/cast/cast.gyp b/media/cast/cast.gyp
index d24b14e..d489a6a 100644
--- a/media/cast/cast.gyp
+++ b/media/cast/cast.gyp
@@ -46,12 +46,15 @@
         'logging/logging_raw.cc',
         'logging/logging_raw.h',
         'logging/raw_event_subscriber.h',
+        'logging/raw_event_subscriber_bundle.cc',
+        'logging/raw_event_subscriber_bundle.h',
+        'logging/receiver_time_offset_estimator.h',
+        'logging/receiver_time_offset_estimator_impl.cc',
+        'logging/receiver_time_offset_estimator_impl.h',
         'logging/simple_event_subscriber.cc',
         'logging/simple_event_subscriber.h',
         'logging/stats_event_subscriber.cc',
         'logging/stats_event_subscriber.h',
-        'logging/stats_util.cc',
-        'logging/stats_util.h',
         'transport/cast_transport_config.cc',
         'transport/cast_transport_config.h',
         'transport/cast_transport_defines.h',
diff --git a/media/cast/cast_testing.gypi b/media/cast/cast_testing.gypi
index cd5e929..f8c2553 100644
--- a/media/cast/cast_testing.gypi
+++ b/media/cast/cast_testing.gypi
@@ -73,6 +73,7 @@
         'logging/serialize_deserialize_test.cc',
         'logging/logging_impl_unittest.cc',
         'logging/logging_raw_unittest.cc',
+        'logging/receiver_time_offset_estimator_impl_unittest.cc',
         'logging/simple_event_subscriber_unittest.cc',
         'logging/stats_event_subscriber_unittest.cc',
         'rtcp/mock_rtcp_receiver_feedback.cc',
@@ -94,6 +95,8 @@
         'rtp_receiver/rtp_parser/test/rtp_packet_builder.cc',
         'rtp_receiver/rtp_parser/rtp_parser_unittest.cc',
         'test/end2end_unittest.cc',
+        'test/fake_receiver_time_offset_estimator.cc',
+        'test/fake_receiver_time_offset_estimator.h',
         'test/fake_single_thread_task_runner.cc',
         'test/fake_single_thread_task_runner.h',
         'test/fake_video_encode_accelerator.cc',
diff --git a/media/cast/logging/logging_defines.cc b/media/cast/logging/logging_defines.cc
index 894b059..e86f02b 100644
--- a/media/cast/logging/logging_defines.cc
+++ b/media/cast/logging/logging_defines.cc
@@ -104,15 +104,5 @@ PacketEvent::PacketEvent()
       type(kUnknown) {}
 PacketEvent::~PacketEvent() {}
 
-FrameLogStats::FrameLogStats()
-    : event_counter(0),
-      sum_size(0) {}
-FrameLogStats::~FrameLogStats() {}
-
-PacketLogStats::PacketLogStats()
-    : event_counter(0),
-      sum_size(0) {}
-PacketLogStats::~PacketLogStats() {}
-
 }  // namespace cast
 }  // namespace media
diff --git a/media/cast/logging/logging_defines.h b/media/cast/logging/logging_defines.h
index 9b9ed51..a87d2d5 100644
--- a/media/cast/logging/logging_defines.h
+++ b/media/cast/logging/logging_defines.h
@@ -107,33 +107,6 @@ struct PacketEvent {
   CastLoggingEvent type;
 };
 
-// Generic statistics given the raw data. More specific data (e.g. frame rate
-// and bit rate) can be computed given the basic metrics.
-// Some of the metrics will only be set when applicable, e.g. delay and size.
-struct FrameLogStats {
-  FrameLogStats();
-  ~FrameLogStats();
-  base::TimeTicks first_event_time;
-  base::TimeTicks last_event_time;
-  int event_counter;
-  size_t sum_size;
-  base::TimeDelta min_delay;
-  base::TimeDelta max_delay;
-  base::TimeDelta sum_delay;
-};
-
-struct PacketLogStats {
-  PacketLogStats();
-  ~PacketLogStats();
-  base::TimeTicks first_event_time;
-  base::TimeTicks last_event_time;
-  int event_counter;
-  size_t sum_size;
-};
-
-typedef std::map<CastLoggingEvent, FrameLogStats> FrameStatsMap;
-typedef std::map<CastLoggingEvent, PacketLogStats> PacketStatsMap;
-
 }  // namespace cast
 }  // namespace media
 
diff --git a/media/cast/logging/raw_event_subscriber_bundle.cc b/media/cast/logging/raw_event_subscriber_bundle.cc
new file mode 100644
index 0000000..1946b6c
--- /dev/null
+++ b/media/cast/logging/raw_event_subscriber_bundle.cc
@@ -0,0 +1,99 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/cast/logging/raw_event_subscriber_bundle.h"
+
+#include "media/cast/cast_environment.h"
+#include "media/cast/logging/receiver_time_offset_estimator_impl.h"
+
+namespace media {
+namespace cast {
+
+RawEventSubscriberBundleForStream::RawEventSubscriberBundleForStream(
+    const scoped_refptr<CastEnvironment>& cast_environment,
+    bool is_audio,
+    ReceiverTimeOffsetEstimator* offset_estimator)
+    : cast_environment_(cast_environment),
+      event_subscriber_(
+          is_audio ? AUDIO_EVENT : VIDEO_EVENT,
+          is_audio ? kMaxAudioEventEntries : kMaxVideoEventEntries),
+      stats_subscriber_(
+          is_audio ? AUDIO_EVENT : VIDEO_EVENT,
+          cast_environment->Clock(), offset_estimator) {
+  cast_environment_->Logging()->AddRawEventSubscriber(&event_subscriber_);
+  cast_environment_->Logging()->AddRawEventSubscriber(&stats_subscriber_);
+}
+
+RawEventSubscriberBundleForStream::~RawEventSubscriberBundleForStream() {
+  cast_environment_->Logging()->RemoveRawEventSubscriber(&event_subscriber_);
+  cast_environment_->Logging()->RemoveRawEventSubscriber(&stats_subscriber_);
+}
+
+EncodingEventSubscriber*
+RawEventSubscriberBundleForStream::GetEncodingEventSubscriber() {
+  return &event_subscriber_;
+}
+
+StatsEventSubscriber*
+RawEventSubscriberBundleForStream::GetStatsEventSubscriber() {
+  return &stats_subscriber_;
+}
+
+RawEventSubscriberBundle::RawEventSubscriberBundle(
+    const scoped_refptr<CastEnvironment>& cast_environment)
+    : cast_environment_(cast_environment) {}
+
+RawEventSubscriberBundle::~RawEventSubscriberBundle() {
+  if (receiver_offset_estimator_.get()) {
+    cast_environment_->Logging()->RemoveRawEventSubscriber(
+        receiver_offset_estimator_.get());
+  }
+}
+
+void RawEventSubscriberBundle::AddEventSubscribers(bool is_audio) {
+  if (!receiver_offset_estimator_.get()) {
+    receiver_offset_estimator_.reset(
+        new ReceiverTimeOffsetEstimatorImpl);
+    cast_environment_->Logging()->AddRawEventSubscriber(
+        receiver_offset_estimator_.get());
+  }
+  SubscribersMapByStream::iterator it = subscribers_.find(is_audio);
+  if (it != subscribers_.end())
+    return;
+
+  subscribers_.insert(std::make_pair(
+      is_audio,
+      make_linked_ptr(new RawEventSubscriberBundleForStream(
+          cast_environment_, is_audio, receiver_offset_estimator_.get()))));
+}
+
+void RawEventSubscriberBundle::RemoveEventSubscribers(bool is_audio) {
+  SubscribersMapByStream::iterator it = subscribers_.find(is_audio);
+  if (it == subscribers_.end())
+    return;
+
+  subscribers_.erase(it);
+  if (subscribers_.empty()) {
+    cast_environment_->Logging()->RemoveRawEventSubscriber(
+        receiver_offset_estimator_.get());
+    receiver_offset_estimator_.reset();
+  }
+}
+
+EncodingEventSubscriber*
+RawEventSubscriberBundle::GetEncodingEventSubscriber(bool is_audio) {
+  SubscribersMapByStream::iterator it = subscribers_.find(is_audio);
+  return it == subscribers_.end() ?
+      NULL : it->second->GetEncodingEventSubscriber();
+}
+
+StatsEventSubscriber*
+RawEventSubscriberBundle::GetStatsEventSubscriber(bool is_audio) {
+  SubscribersMapByStream::iterator it = subscribers_.find(is_audio);
+  return it == subscribers_.end() ?
+      NULL : it->second->GetStatsEventSubscriber();
+}
+
+}  // namespace cast
+}  // namespace media
diff --git a/media/cast/logging/raw_event_subscriber_bundle.h b/media/cast/logging/raw_event_subscriber_bundle.h
new file mode 100644
index 0000000..58ab21e
--- /dev/null
+++ b/media/cast/logging/raw_event_subscriber_bundle.h
@@ -0,0 +1,84 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MEDIA_CAST_LOGGING_RAW_EVENT_SUBSCRIBER_BUNDLE_H_
+#define MEDIA_CAST_LOGGING_RAW_EVENT_SUBSCRIBER_BUNDLE_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "media/cast/logging/encoding_event_subscriber.h"
+#include "media/cast/logging/stats_event_subscriber.h"
+
+namespace media {
+namespace cast {
+
+class CastEnvironment;
+class ReceiverTimeOffsetEstimator;
+
+// Allow 9MB for serialized video / audio event logs.
+const int kMaxSerializedBytes = 9000000;
+
+// Assume serialized log data for each frame will take up to 150 bytes.
+const int kMaxVideoEventEntries = kMaxSerializedBytes / 150;
+
+// Assume serialized log data for each frame will take up to 75 bytes.
+const int kMaxAudioEventEntries = kMaxSerializedBytes / 75;
+
+// A bundle for raw event subscribers for a single stream.
+// It contains an EncodingEventSubscriber and a StatsSubscriber.
+class RawEventSubscriberBundleForStream {
+ public:
+  RawEventSubscriberBundleForStream(
+      const scoped_refptr<CastEnvironment>& cast_environment,
+      bool is_audio,
+      ReceiverTimeOffsetEstimator* offset_estimator);
+  ~RawEventSubscriberBundleForStream();
+
+  EncodingEventSubscriber* GetEncodingEventSubscriber();
+  StatsEventSubscriber* GetStatsEventSubscriber();
+
+ private:
+  const scoped_refptr<CastEnvironment> cast_environment_;
+  EncodingEventSubscriber event_subscriber_;
+  StatsEventSubscriber stats_subscriber_;
+
+  DISALLOW_COPY_AND_ASSIGN(RawEventSubscriberBundleForStream);
+};
+
+// A bundle of subscribers for all streams. An instance of this object
+// is associated with a CastEnvironment.
+// This class can be used for managing event subscribers
+// in a session where they could be multiple streams (i.e. CastSessionDelegate).
+// It also contains a ReceiverTimeOffsetEstimator that is shared by subscribers
+// of different streams.
+class RawEventSubscriberBundle {
+ public:
+  explicit RawEventSubscriberBundle(
+      const scoped_refptr<CastEnvironment>& cast_environment);
+  ~RawEventSubscriberBundle();
+
+  void AddEventSubscribers(bool is_audio);
+  void RemoveEventSubscribers(bool is_audio);
+  EncodingEventSubscriber* GetEncodingEventSubscriber(
+      bool is_audio);
+  StatsEventSubscriber* GetStatsEventSubscriber(bool is_audio);
+
+ private:
+  // Map from (is_audio) -> RawEventSubscriberBundleForStream.
+  // TODO(imcheng): This works because we only have 1 audio and 1 video stream.
+  // This needs to scale better.
+  typedef std::map<bool, linked_ptr<RawEventSubscriberBundleForStream> >
+      SubscribersMapByStream;
+  const scoped_refptr<CastEnvironment> cast_environment_;
+  SubscribersMapByStream subscribers_;
+  scoped_ptr<ReceiverTimeOffsetEstimator> receiver_offset_estimator_;
+
+  DISALLOW_COPY_AND_ASSIGN(RawEventSubscriberBundle);
+};
+
+}  // namespace cast
+}  // namespace media
+
+#endif  // MEDIA_CAST_LOGGING_RAW_EVENT_SUBSCRIBER_BUNDLE_H_
+
diff --git a/media/cast/logging/receiver_time_offset_estimator.h b/media/cast/logging/receiver_time_offset_estimator.h
new file mode 100644
index 0000000..5880a8d
--- /dev/null
+++ b/media/cast/logging/receiver_time_offset_estimator.h
@@ -0,0 +1,39 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MEDIA_CAST_LOGGING_RECEIVER_TIME_OFFSET_ESTIMATOR_H_
+#define MEDIA_CAST_LOGGING_RECEIVER_TIME_OFFSET_ESTIMATOR_H_
+
+#include "base/time/time.h"
+#include "media/cast/logging/raw_event_subscriber.h"
+
+namespace media {
+namespace cast {
+
+// Estimates receiver time offset based on raw events received.
+// In most cases, the sender and receiver run on different time lines.
+// In order to convert receiver time back to sender time (or vice versa)
+// a certain time offset has to be applied.
+// An implementation of this interface listens to raw events to figure out
+// the bounds for the offset value (assuming the true offset value is constant
+// over the lifetime of a cast session).
+// The offset values provided here should be used as follows:
+// - Convert from sender to receiver time: add offset value to sender timestamp.
+// - Convert from receiver to sender time: subtract offset value from receiver
+//   timestamp.
+class ReceiverTimeOffsetEstimator : public RawEventSubscriber {
+ public:
+  virtual ~ReceiverTimeOffsetEstimator() {}
+
+  // If bounds are known, assigns |lower_bound| and |upper_bound| with the
+  // lower bound and upper bound for the offset value, respectively.
+  // Returns true if bounds are known.
+  virtual bool GetReceiverOffsetBounds(base::TimeDelta* lower_bound,
+                                       base::TimeDelta* upper_bound) = 0;
+};
+
+}  // namespace cast
+}  // namespace media
+
+#endif  // MEDIA_CAST_LOGGING_RECEIVER_TIME_OFFSET_ESTIMATOR_H_
diff --git a/media/cast/logging/receiver_time_offset_estimator_impl.cc b/media/cast/logging/receiver_time_offset_estimator_impl.cc
new file mode 100644
index 0000000..897c7e1
--- /dev/null
+++ b/media/cast/logging/receiver_time_offset_estimator_impl.cc
@@ -0,0 +1,125 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <algorithm>
+#include <utility>
+
+#include "base/logging.h"
+#include "media/cast/logging/receiver_time_offset_estimator_impl.h"
+
+namespace media {
+namespace cast {
+
+// This should be large enough so that we can collect all 3 events before
+// the entry gets removed from the map.
+const size_t kMaxEventTimesMapSize = 100;
+
+ReceiverTimeOffsetEstimatorImpl::ReceiverTimeOffsetEstimatorImpl()
+    : bounded_(false) {}
+
+ReceiverTimeOffsetEstimatorImpl::~ReceiverTimeOffsetEstimatorImpl() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+}
+
+void ReceiverTimeOffsetEstimatorImpl::OnReceiveFrameEvent(
+    const FrameEvent& frame_event) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  CastLoggingEvent event = frame_event.type;
+  if (event != kVideoFrameEncoded && event != kVideoAckSent &&
+      event != kVideoAckReceived)
+    return;
+
+  EventTimesMap::iterator it = event_times_map_.find(frame_event.rtp_timestamp);
+  if (it == event_times_map_.end()) {
+    EventTimes event_times;
+    it = event_times_map_.insert(std::make_pair(frame_event.rtp_timestamp,
+                                                event_times)).first;
+  }
+  switch (event) {
+    case kVideoFrameEncoded:
+      // Encode is supposed to happen only once. If we see duplicate event,
+      // throw away the entry.
+      if (it->second.event_a_time.is_null()) {
+        it->second.event_a_time = frame_event.timestamp;
+      } else {
+        event_times_map_.erase(it);
+        return;
+      }
+      break;
+    case kVideoAckSent:
+      if (it->second.event_b_time.is_null()) {
+        it->second.event_b_time = frame_event.timestamp;
+      } else if (it->second.event_b_time != frame_event.timestamp) {
+        // Duplicate ack sent events are normal due to RTCP redundancy,
+        // but they must have the same event timestamp.
+        event_times_map_.erase(it);
+        return;
+      }
+      break;
+    case kVideoAckReceived:
+      // If there are duplicate ack received events, pick the one with the
+      // smallest event timestamp so we can get a better bound.
+      if (it->second.event_c_time.is_null()) {
+        it->second.event_c_time = frame_event.timestamp;
+      } else {
+        it->second.event_c_time =
+            std::min(frame_event.timestamp, it->second.event_c_time);
+      }
+      break;
+    default:
+      NOTREACHED();
+  }
+
+  if (!it->second.event_a_time.is_null() &&
+      !it->second.event_b_time.is_null() &&
+      !it->second.event_c_time.is_null()) {
+    UpdateOffsetBounds(it->second);
+    event_times_map_.erase(it);
+  }
+
+  // Keep the map size at most |kMaxEventTimesMapSize|.
+  if (event_times_map_.size() > kMaxEventTimesMapSize)
+    event_times_map_.erase(event_times_map_.begin());
+}
+
+bool ReceiverTimeOffsetEstimatorImpl::GetReceiverOffsetBounds(
+    base::TimeDelta* lower_bound,
+    base::TimeDelta* upper_bound) {
+  if (!bounded_)
+    return false;
+
+  *lower_bound = offset_lower_bound_;
+  *upper_bound = offset_upper_bound_;
+  return true;
+}
+
+void ReceiverTimeOffsetEstimatorImpl::OnReceivePacketEvent(
+    const PacketEvent& packet_event) {
+  // Not interested in packet events.
+  DCHECK(thread_checker_.CalledOnValidThread());
+}
+
+void ReceiverTimeOffsetEstimatorImpl::UpdateOffsetBounds(
+    const EventTimes& event) {
+  base::TimeDelta lower_bound = event.event_b_time - event.event_c_time;
+  base::TimeDelta upper_bound = event.event_b_time - event.event_a_time;
+
+  if (bounded_) {
+    lower_bound = std::max(lower_bound, offset_lower_bound_);
+    upper_bound = std::min(upper_bound, offset_upper_bound_);
+  }
+
+  if (lower_bound > upper_bound) {
+    VLOG(2) << "Got bogus offset bound values [" << lower_bound.InMilliseconds()
+            << ", " << upper_bound.InMilliseconds() << "].";
+    return;
+  }
+
+  offset_lower_bound_ = lower_bound;
+  offset_upper_bound_ = upper_bound;
+  bounded_ = true;
+}
+
+}  // namespace cast
+}  // namespace media
diff --git a/media/cast/logging/receiver_time_offset_estimator_impl.h b/media/cast/logging/receiver_time_offset_estimator_impl.h
new file mode 100644
index 0000000..0968bed
--- /dev/null
+++ b/media/cast/logging/receiver_time_offset_estimator_impl.h
@@ -0,0 +1,64 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MEDIA_CAST_LOGGING_RECEIVER_TIME_OFFSET_ESTIMATOR_IMPL_H_
+#define MEDIA_CAST_LOGGING_RECEIVER_TIME_OFFSET_ESTIMATOR_IMPL_H_
+
+#include "base/time/time.h"
+#include "base/threading/thread_checker.h"
+#include "media/cast/logging/logging_defines.h"
+#include "media/cast/logging/receiver_time_offset_estimator.h"
+
+namespace media {
+namespace cast {
+
+// This implementation listens to three types of events:
+// 1. kVideoFrameEncoded (sender side)
+// 2. kVideoAckSent (receiver side)
+// 3. kVideoAckReceived (sender side)
+// There is a causal relationship between these events in that these events
+// must happen in order. This class obtains the lower and upper bounds for
+// the offset by taking the difference of timestamps (2) - (1) and (2) - (3),
+// respectively.
+// The bound will become better as the latency between the events decreases.
+class ReceiverTimeOffsetEstimatorImpl : public ReceiverTimeOffsetEstimator {
+ public:
+  ReceiverTimeOffsetEstimatorImpl();
+
+  virtual ~ReceiverTimeOffsetEstimatorImpl();
+
+  // RawEventSubscriber implementations.
+  virtual void OnReceiveFrameEvent(const FrameEvent& frame_event) OVERRIDE;
+  virtual void OnReceivePacketEvent(const PacketEvent& packet_event) OVERRIDE;
+
+  // ReceiverTimeOffsetEstimator implementation.
+  virtual bool GetReceiverOffsetBounds(base::TimeDelta* lower_bound,
+                                       base::TimeDelta* upper_bound) OVERRIDE;
+
+ private:
+  struct EventTimes {
+    base::TimeTicks event_a_time;
+    base::TimeTicks event_b_time;
+    base::TimeTicks event_c_time;
+  };
+
+  typedef std::map<RtpTimestamp, EventTimes> EventTimesMap;
+
+  void UpdateOffsetBounds(const EventTimes& event);
+
+  // Fixed size storage to store event times for recent frames.
+  EventTimesMap event_times_map_;
+
+  bool bounded_;
+  base::TimeDelta offset_lower_bound_;
+  base::TimeDelta offset_upper_bound_;
+
+  base::ThreadChecker thread_checker_;
+  DISALLOW_COPY_AND_ASSIGN(ReceiverTimeOffsetEstimatorImpl);
+};
+
+}  // namespace cast
+}  // namespace media
+
+#endif  // MEDIA_CAST_LOGGING_RECEIVER_TIME_OFFSET_ESTIMATOR_IMPL_H_
diff --git a/media/cast/logging/receiver_time_offset_estimator_impl_unittest.cc b/media/cast/logging/receiver_time_offset_estimator_impl_unittest.cc
new file mode 100644
index 0000000..36985b6
--- /dev/null
+++ b/media/cast/logging/receiver_time_offset_estimator_impl_unittest.cc
@@ -0,0 +1,234 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/test/simple_test_tick_clock.h"
+#include "base/time/tick_clock.h"
+#include "media/cast/cast_environment.h"
+#include "media/cast/logging/logging_defines.h"
+#include "media/cast/logging/receiver_time_offset_estimator_impl.h"
+#include "media/cast/test/fake_single_thread_task_runner.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace media {
+namespace cast {
+
+class ReceiverTimeOffsetEstimatorImplTest : public ::testing::Test {
+ protected:
+  ReceiverTimeOffsetEstimatorImplTest()
+      : sender_clock_(new base::SimpleTestTickClock()),
+        task_runner_(new test::FakeSingleThreadTaskRunner(sender_clock_)),
+        cast_environment_(new CastEnvironment(
+            scoped_ptr<base::TickClock>(sender_clock_).Pass(),
+            task_runner_,
+            task_runner_,
+            task_runner_)) {
+    cast_environment_->Logging()->AddRawEventSubscriber(&estimator_);
+  }
+
+  virtual ~ReceiverTimeOffsetEstimatorImplTest() {
+    cast_environment_->Logging()->RemoveRawEventSubscriber(&estimator_);
+  }
+
+  void AdvanceClocks(base::TimeDelta time) {
+    sender_clock_->Advance(time);
+    receiver_clock_.Advance(time);
+  }
+
+  base::SimpleTestTickClock* sender_clock_;  // Owned by CastEnvironment.
+  scoped_refptr<test::FakeSingleThreadTaskRunner> task_runner_;
+  scoped_refptr<CastEnvironment> cast_environment_;
+  base::SimpleTestTickClock receiver_clock_;
+  ReceiverTimeOffsetEstimatorImpl estimator_;
+};
+
+// Suppose the true offset is 100ms.
+// Event A occurred at sender time 20ms.
+// Event B occurred at receiver time 130ms. (sender time 30ms)
+// Event C occurred at sender time 60ms.
+// Then the bound after all 3 events have arrived is [130-60=70, 130-20=110].
+TEST_F(ReceiverTimeOffsetEstimatorImplTest, EstimateOffset) {
+  int64 true_offset_ms = 100;
+  receiver_clock_.Advance(base::TimeDelta::FromMilliseconds(true_offset_ms));
+
+  base::TimeDelta lower_bound;
+  base::TimeDelta upper_bound;
+
+  EXPECT_FALSE(estimator_.GetReceiverOffsetBounds(&lower_bound, &upper_bound));
+
+  RtpTimestamp rtp_timestamp = 0;
+  uint32 frame_id = 0;
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(20));
+
+  cast_environment_->Logging()->InsertEncodedFrameEvent(
+      sender_clock_->NowTicks(),
+      kVideoFrameEncoded,
+      rtp_timestamp,
+      frame_id,
+      1234,
+      true,
+      5678);
+
+  EXPECT_FALSE(estimator_.GetReceiverOffsetBounds(&lower_bound, &upper_bound));
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(10));
+  cast_environment_->Logging()->InsertFrameEvent(
+      receiver_clock_.NowTicks(), kVideoAckSent, rtp_timestamp, frame_id);
+
+  EXPECT_FALSE(estimator_.GetReceiverOffsetBounds(&lower_bound, &upper_bound));
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(30));
+  cast_environment_->Logging()->InsertFrameEvent(
+      sender_clock_->NowTicks(), kVideoAckReceived, rtp_timestamp, frame_id);
+
+  EXPECT_TRUE(estimator_.GetReceiverOffsetBounds(&lower_bound, &upper_bound));
+
+  int64 lower_bound_ms = lower_bound.InMilliseconds();
+  int64 upper_bound_ms = upper_bound.InMilliseconds();
+  EXPECT_EQ(70, lower_bound_ms);
+  EXPECT_EQ(110, upper_bound_ms);
+  EXPECT_GE(true_offset_ms, lower_bound_ms);
+  EXPECT_LE(true_offset_ms, upper_bound_ms);
+}
+
+// Same scenario as above, but event C arrives before event B. It doens't mean
+// event C occurred before event B.
+TEST_F(ReceiverTimeOffsetEstimatorImplTest, EventCArrivesBeforeEventB) {
+  int64 true_offset_ms = 100;
+  receiver_clock_.Advance(base::TimeDelta::FromMilliseconds(true_offset_ms));
+
+  base::TimeDelta lower_bound;
+  base::TimeDelta upper_bound;
+
+  EXPECT_FALSE(estimator_.GetReceiverOffsetBounds(&lower_bound, &upper_bound));
+
+  RtpTimestamp rtp_timestamp = 0;
+  uint32 frame_id = 0;
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(20));
+
+  cast_environment_->Logging()->InsertEncodedFrameEvent(
+      sender_clock_->NowTicks(),
+      kVideoFrameEncoded,
+      rtp_timestamp,
+      frame_id,
+      1234,
+      true,
+      5678);
+
+  EXPECT_FALSE(estimator_.GetReceiverOffsetBounds(&lower_bound, &upper_bound));
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(10));
+  base::TimeTicks event_b_time = receiver_clock_.NowTicks();
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(30));
+  base::TimeTicks event_c_time = sender_clock_->NowTicks();
+
+  cast_environment_->Logging()->InsertFrameEvent(
+      event_c_time, kVideoAckReceived, rtp_timestamp, frame_id);
+
+  EXPECT_FALSE(estimator_.GetReceiverOffsetBounds(&lower_bound, &upper_bound));
+
+  cast_environment_->Logging()->InsertFrameEvent(
+      event_b_time, kVideoAckSent, rtp_timestamp, frame_id);
+
+  EXPECT_TRUE(estimator_.GetReceiverOffsetBounds(&lower_bound, &upper_bound));
+
+  int64 lower_bound_ms = lower_bound.InMilliseconds();
+  int64 upper_bound_ms = upper_bound.InMilliseconds();
+  EXPECT_EQ(70, lower_bound_ms);
+  EXPECT_EQ(110, upper_bound_ms);
+  EXPECT_GE(true_offset_ms, lower_bound_ms);
+  EXPECT_LE(true_offset_ms, upper_bound_ms);
+}
+
+TEST_F(ReceiverTimeOffsetEstimatorImplTest, MultipleIterations) {
+  int64 true_offset_ms = 100;
+  receiver_clock_.Advance(base::TimeDelta::FromMilliseconds(true_offset_ms));
+
+  base::TimeDelta lower_bound;
+  base::TimeDelta upper_bound;
+
+  RtpTimestamp rtp_timestamp_a = 0;
+  int frame_id_a = 0;
+  RtpTimestamp rtp_timestamp_b = 90;
+  int frame_id_b = 1;
+  RtpTimestamp rtp_timestamp_c = 180;
+  int frame_id_c = 2;
+
+  // Frame 1 times: [20, 30+100, 60]
+  // Frame 2 times: [30, 50+100, 55]
+  // Frame 3 times: [77, 80+100, 110]
+  // Bound should end up at [95, 103]
+  // Events times in chronological order: 20, 30 x2, 50, 55, 60, 77, 80, 110
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(20));
+  cast_environment_->Logging()->InsertEncodedFrameEvent(
+      sender_clock_->NowTicks(),
+      kVideoFrameEncoded,
+      rtp_timestamp_a,
+      frame_id_a,
+      1234,
+      true,
+      5678);
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(10));
+  cast_environment_->Logging()->InsertEncodedFrameEvent(
+      sender_clock_->NowTicks(),
+      kVideoFrameEncoded,
+      rtp_timestamp_b,
+      frame_id_b,
+      1234,
+      true,
+      5678);
+  cast_environment_->Logging()->InsertFrameEvent(
+      receiver_clock_.NowTicks(), kVideoAckSent, rtp_timestamp_a, frame_id_a);
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(20));
+  cast_environment_->Logging()->InsertFrameEvent(
+      receiver_clock_.NowTicks(), kVideoAckSent, rtp_timestamp_b, frame_id_b);
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(5));
+  cast_environment_->Logging()->InsertFrameEvent(sender_clock_->NowTicks(),
+                                                 kVideoAckReceived,
+                                                 rtp_timestamp_b,
+                                                 frame_id_b);
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(5));
+  cast_environment_->Logging()->InsertFrameEvent(sender_clock_->NowTicks(),
+                                                 kVideoAckReceived,
+                                                 rtp_timestamp_a,
+                                                 frame_id_a);
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(17));
+  cast_environment_->Logging()->InsertEncodedFrameEvent(
+      sender_clock_->NowTicks(),
+      kVideoFrameEncoded,
+      rtp_timestamp_c,
+      frame_id_c,
+      1234,
+      true,
+      5678);
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(3));
+  cast_environment_->Logging()->InsertFrameEvent(
+      receiver_clock_.NowTicks(), kVideoAckSent, rtp_timestamp_c, frame_id_c);
+
+  AdvanceClocks(base::TimeDelta::FromMilliseconds(30));
+  cast_environment_->Logging()->InsertFrameEvent(sender_clock_->NowTicks(),
+                                                 kVideoAckReceived,
+                                                 rtp_timestamp_c,
+                                                 frame_id_c);
+
+  EXPECT_TRUE(estimator_.GetReceiverOffsetBounds(&lower_bound, &upper_bound));
+  int64 lower_bound_ms = lower_bound.InMilliseconds();
+  int64 upper_bound_ms = upper_bound.InMilliseconds();
+  EXPECT_EQ(95, lower_bound_ms);
+  EXPECT_EQ(103, upper_bound_ms);
+  EXPECT_GE(true_offset_ms, lower_bound_ms);
+  EXPECT_LE(true_offset_ms, upper_bound_ms);
+}
+
+}  // namespace cast
+}  // namespace media
diff --git a/media/cast/logging/stats_event_subscriber.cc b/media/cast/logging/stats_event_subscriber.cc
index 2b40c99..008add1 100644
--- a/media/cast/logging/stats_event_subscriber.cc
+++ b/media/cast/logging/stats_event_subscriber.cc
@@ -5,12 +5,83 @@
 #include "media/cast/logging/stats_event_subscriber.h"
 
 #include "base/logging.h"
+#include "base/values.h"
+
+#define STAT_ENUM_TO_STRING(enum) \
+  case enum:                      \
+    return #enum
 
 namespace media {
 namespace cast {
 
-StatsEventSubscriber::StatsEventSubscriber(EventMediaType event_media_type)
-    : event_media_type_(event_media_type) {}
+namespace {
+
+using media::cast::CastLoggingEvent;
+using media::cast::EventMediaType;
+
+const size_t kMaxFrameEventTimeMapSize = 100;
+const size_t kMaxPacketEventTimeMapSize = 1000;
+
+CastLoggingEvent GetCapturedEvent(EventMediaType media_type) {
+  return media_type == AUDIO_EVENT ? kAudioFrameCaptured : kVideoFrameCaptured;
+}
+
+CastLoggingEvent GetEncodedEvent(EventMediaType media_type) {
+  return media_type == AUDIO_EVENT ? kAudioFrameEncoded : kVideoFrameEncoded;
+}
+
+CastLoggingEvent GetDecodedEvent(EventMediaType media_type) {
+  return media_type == AUDIO_EVENT ? kAudioFrameDecoded : kVideoFrameDecoded;
+}
+
+CastLoggingEvent GetPlayoutEvent(EventMediaType media_type) {
+  return media_type == AUDIO_EVENT ? kAudioPlayoutDelay : kVideoRenderDelay;
+}
+
+CastLoggingEvent GetPacketSentEvent(EventMediaType media_type) {
+  return media_type == AUDIO_EVENT ? kAudioPacketSentToNetwork :
+                                     kVideoPacketSentToNetwork;
+}
+
+CastLoggingEvent GetPacketReceivedEvent(EventMediaType media_type) {
+  return media_type == AUDIO_EVENT ? kAudioPacketReceived :
+                                     kVideoPacketReceived;
+}
+
+CastLoggingEvent GetPacketRetransmittedEvent(EventMediaType media_type) {
+  return media_type == AUDIO_EVENT ? kAudioPacketRetransmitted :
+                                     kVideoPacketRetransmitted;
+}
+
+bool IsReceiverEvent(CastLoggingEvent event) {
+  return event == kAudioFrameDecoded
+      || event == kVideoFrameDecoded
+      || event == kAudioPlayoutDelay
+      || event == kVideoRenderDelay
+      || event == kAudioAckSent
+      || event == kVideoAckSent
+      || event == kAudioPacketReceived
+      || event == kVideoPacketReceived
+      || event == kDuplicateAudioPacketReceived
+      || event == kDuplicateVideoPacketReceived;
+}
+
+}  // namespace
+
+StatsEventSubscriber::StatsEventSubscriber(
+    EventMediaType event_media_type,
+    base::TickClock* clock,
+    ReceiverTimeOffsetEstimator* offset_estimator)
+    : event_media_type_(event_media_type),
+      clock_(clock),
+      offset_estimator_(offset_estimator),
+      network_latency_datapoints_(0),
+      e2e_latency_datapoints_(0) {
+  DCHECK(event_media_type == AUDIO_EVENT || event_media_type == VIDEO_EVENT);
+  base::TimeTicks now = clock_->NowTicks();
+  start_time_ = now;
+  last_response_received_time_ = base::TimeTicks();
+}
 
 StatsEventSubscriber::~StatsEventSubscriber() {
   DCHECK(thread_checker_.CalledOnValidThread());
@@ -26,24 +97,24 @@ void StatsEventSubscriber::OnReceiveFrameEvent(const FrameEvent& frame_event) {
   FrameStatsMap::iterator it = frame_stats_.find(type);
   if (it == frame_stats_.end()) {
     FrameLogStats stats;
-    stats.first_event_time = frame_event.timestamp;
-    stats.last_event_time = frame_event.timestamp;
     stats.event_counter = 1;
     stats.sum_size = frame_event.size;
-    stats.min_delay = frame_event.delay_delta;
-    stats.max_delay = frame_event.delay_delta;
     stats.sum_delay = frame_event.delay_delta;
     frame_stats_.insert(std::make_pair(type, stats));
   } else {
     ++(it->second.event_counter);
-    it->second.last_event_time = frame_event.timestamp;
     it->second.sum_size += frame_event.size;
     it->second.sum_delay += frame_event.delay_delta;
-    if (frame_event.delay_delta > it->second.max_delay)
-      it->second.max_delay = frame_event.delay_delta;
-    if (frame_event.delay_delta < it->second.min_delay)
-      it->second.min_delay = frame_event.delay_delta;
   }
+
+  if (type == GetCapturedEvent(event_media_type_)) {
+    RecordFrameCapturedTime(frame_event);
+  } else if (type == GetPlayoutEvent(event_media_type_)) {
+    RecordE2ELatency(frame_event);
+  }
+
+  if (IsReceiverEvent(type))
+    UpdateLastResponseTime(frame_event.timestamp);
 }
 
 void StatsEventSubscriber::OnReceivePacketEvent(
@@ -57,33 +128,42 @@ void StatsEventSubscriber::OnReceivePacketEvent(
   PacketStatsMap::iterator it = packet_stats_.find(type);
   if (it == packet_stats_.end()) {
     PacketLogStats stats;
-    stats.first_event_time = packet_event.timestamp;
-    stats.last_event_time = packet_event.timestamp;
     stats.event_counter = 1;
     stats.sum_size = packet_event.size;
     packet_stats_.insert(std::make_pair(type, stats));
   } else {
-    it->second.last_event_time = packet_event.timestamp;
     ++(it->second.event_counter);
     it->second.sum_size += packet_event.size;
   }
-}
 
-void StatsEventSubscriber::GetFrameStats(FrameStatsMap* frame_stats_map) const {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  DCHECK(frame_stats_map);
+  if (type == GetPacketSentEvent(event_media_type_) ||
+      type == GetPacketReceivedEvent(event_media_type_)) {
+    RecordNetworkLatency(packet_event);
+  } else if (type == GetPacketRetransmittedEvent(event_media_type_)) {
+    // We only measure network latency using packets that doesn't have to be
+    // retransmitted as there is precisely one sent-receive timestamp pairs.
+    ErasePacketSentTime(packet_event);
+  }
 
-  frame_stats_map->clear();
-  frame_stats_map->insert(frame_stats_.begin(), frame_stats_.end());
+  if (IsReceiverEvent(type))
+    UpdateLastResponseTime(packet_event.timestamp);
 }
 
-void StatsEventSubscriber::GetPacketStats(
-    PacketStatsMap* packet_stats_map) const {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  DCHECK(packet_stats_map);
+scoped_ptr<base::DictionaryValue> StatsEventSubscriber::GetStats() const {
+  StatsMap stats_map;
+  GetStatsInternal(&stats_map);
+  scoped_ptr<base::DictionaryValue> ret(new base::DictionaryValue);
 
-  packet_stats_map->clear();
-  packet_stats_map->insert(packet_stats_.begin(), packet_stats_.end());
+  scoped_ptr<base::DictionaryValue> stats(new base::DictionaryValue);
+  for (StatsMap::const_iterator it = stats_map.begin(); it != stats_map.end();
+       ++it) {
+    stats->SetDouble(CastStatToString(it->first), it->second);
+  }
+
+  ret->Set(event_media_type_ == AUDIO_EVENT ? "audio" : "video",
+           stats.release());
+
+  return ret.Pass();
 }
 
 void StatsEventSubscriber::Reset() {
@@ -91,7 +171,272 @@ void StatsEventSubscriber::Reset() {
 
   frame_stats_.clear();
   packet_stats_.clear();
+  total_network_latency_ = base::TimeDelta();
+  network_latency_datapoints_ = 0;
+  total_e2e_latency_ = base::TimeDelta();
+  e2e_latency_datapoints_ = 0;
+  frame_captured_times_.clear();
+  packet_sent_times_.clear();
+  start_time_ = clock_->NowTicks();
+  last_response_received_time_ = base::TimeTicks();
+}
+
+// static
+const char* StatsEventSubscriber::CastStatToString(CastStat stat) {
+  switch (stat) {
+    STAT_ENUM_TO_STRING(CAPTURE_FPS);
+    STAT_ENUM_TO_STRING(ENCODE_FPS);
+    STAT_ENUM_TO_STRING(DECODE_FPS);
+    STAT_ENUM_TO_STRING(AVG_ENCODE_TIME_MS);
+    STAT_ENUM_TO_STRING(AVG_PLAYOUT_DELAY_MS);
+    STAT_ENUM_TO_STRING(AVG_NETWORK_LATENCY_MS);
+    STAT_ENUM_TO_STRING(AVG_E2E_LATENCY_MS);
+    STAT_ENUM_TO_STRING(ENCODE_KBPS);
+    STAT_ENUM_TO_STRING(TRANSMISSION_KBPS);
+    STAT_ENUM_TO_STRING(RETRANSMISSION_KBPS);
+    STAT_ENUM_TO_STRING(PACKET_LOSS_FRACTION);
+    STAT_ENUM_TO_STRING(MS_SINCE_LAST_RECEIVER_RESPONSE);
+  }
+  NOTREACHED();
+  return "";
+}
+
+void StatsEventSubscriber::GetStatsInternal(StatsMap* stats_map) const {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  stats_map->clear();
+
+  base::TimeTicks end_time = clock_->NowTicks();
+
+  PopulateFpsStat(
+      end_time, GetCapturedEvent(event_media_type_), CAPTURE_FPS, stats_map);
+  PopulateFpsStat(
+      end_time, GetEncodedEvent(event_media_type_), ENCODE_FPS, stats_map);
+  PopulateFpsStat(
+      end_time, GetDecodedEvent(event_media_type_), DECODE_FPS, stats_map);
+  PopulatePlayoutDelayStat(stats_map);
+  PopulateFrameBitrateStat(end_time, stats_map);
+  PopulatePacketBitrateStat(end_time,
+                            GetPacketSentEvent(event_media_type_),
+                            TRANSMISSION_KBPS,
+                            stats_map);
+  PopulatePacketBitrateStat(end_time,
+                            GetPacketRetransmittedEvent(event_media_type_),
+                            RETRANSMISSION_KBPS,
+                            stats_map);
+  PopulatePacketLossPercentageStat(stats_map);
+
+  if (network_latency_datapoints_ > 0) {
+    double avg_network_latency_ms =
+        total_network_latency_.InMillisecondsF() /
+        network_latency_datapoints_;
+    stats_map->insert(
+        std::make_pair(AVG_NETWORK_LATENCY_MS, avg_network_latency_ms));
+  }
+
+  if (e2e_latency_datapoints_ > 0) {
+    double avg_e2e_latency_ms =
+        total_e2e_latency_.InMillisecondsF() / e2e_latency_datapoints_;
+    stats_map->insert(std::make_pair(AVG_E2E_LATENCY_MS, avg_e2e_latency_ms));
+  }
+
+  if (!last_response_received_time_.is_null()) {
+    stats_map->insert(
+        std::make_pair(MS_SINCE_LAST_RECEIVER_RESPONSE,
+        (end_time - last_response_received_time_).InMillisecondsF()));
+  }
+}
+
+bool StatsEventSubscriber::GetReceiverOffset(base::TimeDelta* offset) {
+  base::TimeDelta receiver_offset_lower_bound;
+  base::TimeDelta receiver_offset_upper_bound;
+  if (!offset_estimator_->GetReceiverOffsetBounds(
+          &receiver_offset_lower_bound, &receiver_offset_upper_bound)) {
+    return false;
+  }
+
+  *offset = (receiver_offset_lower_bound + receiver_offset_upper_bound) / 2;
+  return true;
+}
+
+void StatsEventSubscriber::RecordFrameCapturedTime(
+    const FrameEvent& frame_event) {
+  frame_captured_times_.insert(
+      std::make_pair(frame_event.rtp_timestamp, frame_event.timestamp));
+  if (frame_captured_times_.size() > kMaxFrameEventTimeMapSize)
+    frame_captured_times_.erase(frame_captured_times_.begin());
+}
+
+void StatsEventSubscriber::RecordE2ELatency(const FrameEvent& frame_event) {
+  base::TimeDelta receiver_offset;
+  if (!GetReceiverOffset(&receiver_offset))
+    return;
+
+  FrameEventTimeMap::iterator it =
+      frame_captured_times_.find(frame_event.rtp_timestamp);
+  if (it == frame_captured_times_.end())
+    return;
+
+  // Playout time is event time + playout delay.
+  base::TimeTicks playout_time =
+      frame_event.timestamp + frame_event.delay_delta - receiver_offset;
+  total_e2e_latency_ += playout_time - it->second;
+  e2e_latency_datapoints_++;
+}
+
+void StatsEventSubscriber::UpdateLastResponseTime(
+    base::TimeTicks receiver_time) {
+  base::TimeDelta receiver_offset;
+  if (!GetReceiverOffset(&receiver_offset))
+    return;
+  base::TimeTicks sender_time = receiver_time - receiver_offset;
+  last_response_received_time_ = sender_time;
+}
+
+void StatsEventSubscriber::ErasePacketSentTime(
+    const PacketEvent& packet_event) {
+  std::pair<RtpTimestamp, uint16> key(
+      std::make_pair(packet_event.rtp_timestamp, packet_event.packet_id));
+  packet_sent_times_.erase(key);
+}
+
+void StatsEventSubscriber::RecordNetworkLatency(
+    const PacketEvent& packet_event) {
+  base::TimeDelta receiver_offset;
+  if (!GetReceiverOffset(&receiver_offset))
+    return;
+
+  std::pair<RtpTimestamp, uint16> key(
+      std::make_pair(packet_event.rtp_timestamp, packet_event.packet_id));
+  PacketEventTimeMap::iterator it = packet_sent_times_.find(key);
+  if (it == packet_sent_times_.end()) {
+    std::pair<RtpTimestamp, uint16> key(
+        std::make_pair(packet_event.rtp_timestamp, packet_event.packet_id));
+    std::pair<base::TimeTicks, CastLoggingEvent> value =
+        std::make_pair(packet_event.timestamp, packet_event.type);
+    packet_sent_times_.insert(std::make_pair(key, value));
+    if (packet_sent_times_.size() > kMaxPacketEventTimeMapSize)
+      packet_sent_times_.erase(packet_sent_times_.begin());
+  } else {
+    std::pair<base::TimeTicks, CastLoggingEvent> value = it->second;
+    CastLoggingEvent recorded_type = value.second;
+    bool match = false;
+    base::TimeTicks packet_sent_time;
+    base::TimeTicks packet_received_time;
+    if (recorded_type == GetPacketSentEvent(event_media_type_) &&
+        packet_event.type == GetPacketReceivedEvent(event_media_type_)) {
+      packet_sent_time = value.first;
+      packet_received_time = packet_event.timestamp;
+      match = true;
+    } else if (recorded_type == GetPacketReceivedEvent(event_media_type_) &&
+        packet_event.type == GetPacketSentEvent(event_media_type_)) {
+      packet_sent_time = packet_event.timestamp;
+      packet_received_time = value.first;
+      match = true;
+    }
+    if (match) {
+      // Subtract by offset.
+      packet_received_time -= receiver_offset;
+
+      total_network_latency_ += packet_received_time - packet_sent_time;
+      network_latency_datapoints_++;
+      packet_sent_times_.erase(it);
+    }
+  }
+}
+
+void StatsEventSubscriber::PopulateFpsStat(base::TimeTicks end_time,
+                                           CastLoggingEvent event,
+                                           CastStat stat,
+                                           StatsMap* stats_map) const {
+  FrameStatsMap::const_iterator it = frame_stats_.find(event);
+  if (it != frame_stats_.end()) {
+    double fps = 0.0;
+    base::TimeDelta duration = (end_time - start_time_);
+    int count = it->second.event_counter;
+    if (duration > base::TimeDelta())
+      fps = count / duration.InSecondsF();
+    stats_map->insert(std::make_pair(stat, fps));
+  }
+}
+
+void StatsEventSubscriber::PopulatePlayoutDelayStat(StatsMap* stats_map) const {
+  CastLoggingEvent event = GetPlayoutEvent(event_media_type_);
+  FrameStatsMap::const_iterator it = frame_stats_.find(event);
+  if (it != frame_stats_.end()) {
+    double avg_delay_ms = 0.0;
+    base::TimeDelta sum_delay = it->second.sum_delay;
+    int count = it->second.event_counter;
+    if (count != 0)
+      avg_delay_ms = sum_delay.InMillisecondsF() / count;
+    stats_map->insert(std::make_pair(AVG_PLAYOUT_DELAY_MS, avg_delay_ms));
+  }
 }
 
+void StatsEventSubscriber::PopulateFrameBitrateStat(base::TimeTicks end_time,
+                                                    StatsMap* stats_map) const {
+  CastLoggingEvent event = GetEncodedEvent(event_media_type_);
+  FrameStatsMap::const_iterator it = frame_stats_.find(event);
+  if (it != frame_stats_.end()) {
+    double kbps = 0.0;
+    base::TimeDelta duration = end_time - start_time_;
+    if (duration > base::TimeDelta()) {
+      kbps = it->second.sum_size / duration.InMillisecondsF() * 8;
+    }
+
+    stats_map->insert(std::make_pair(ENCODE_KBPS, kbps));
+  }
+}
+
+void StatsEventSubscriber::PopulatePacketBitrateStat(
+    base::TimeTicks end_time,
+    CastLoggingEvent event,
+    CastStat stat,
+    StatsMap* stats_map) const {
+  PacketStatsMap::const_iterator it = packet_stats_.find(event);
+  if (it != packet_stats_.end()) {
+    double kbps = 0;
+    base::TimeDelta duration = end_time - start_time_;
+    if (duration > base::TimeDelta()) {
+      kbps = it->second.sum_size / duration.InMillisecondsF() * 8;
+    }
+
+    stats_map->insert(std::make_pair(stat, kbps));
+  }
+}
+
+void StatsEventSubscriber::PopulatePacketLossPercentageStat(
+    StatsMap* stats_map) const {
+  // We assume that retransmission means that the packet's previous
+  // (re)transmission was lost.
+  // This means the percentage of packet loss is
+  // (# of retransmit events) / (# of transmit + retransmit events).
+  CastLoggingEvent packet_sent_event = GetPacketSentEvent(event_media_type_);
+  CastLoggingEvent packet_retransmitted_event =
+      GetPacketRetransmittedEvent(event_media_type_);
+  PacketStatsMap::const_iterator sent_it =
+      packet_stats_.find(packet_sent_event);
+  if (sent_it == packet_stats_.end())
+    return;
+  PacketStatsMap::const_iterator retransmitted_it =
+      packet_stats_.find(packet_retransmitted_event);
+  int sent_count = sent_it->second.event_counter;
+  int retransmitted_count = 0;
+  if (retransmitted_it != packet_stats_.end())
+    retransmitted_count = retransmitted_it->second.event_counter;
+  double packet_loss_fraction = static_cast<double>(retransmitted_count) /
+                                (sent_count + retransmitted_count);
+  stats_map->insert(
+      std::make_pair(PACKET_LOSS_FRACTION, packet_loss_fraction));
+}
+
+StatsEventSubscriber::FrameLogStats::FrameLogStats()
+    : event_counter(0), sum_size(0) {}
+StatsEventSubscriber::FrameLogStats::~FrameLogStats() {}
+
+StatsEventSubscriber::PacketLogStats::PacketLogStats()
+    : event_counter(0), sum_size(0) {}
+StatsEventSubscriber::PacketLogStats::~PacketLogStats() {}
+
 }  // namespace cast
 }  // namespace media
diff --git a/media/cast/logging/stats_event_subscriber.h b/media/cast/logging/stats_event_subscriber.h
index 176ced8..4e198da 100644
--- a/media/cast/logging/stats_event_subscriber.h
+++ b/media/cast/logging/stats_event_subscriber.h
@@ -5,18 +5,30 @@
 #ifndef MEDIA_CAST_LOGGING_STATS_EVENT_SUBSCRIBER_H_
 #define MEDIA_CAST_LOGGING_STATS_EVENT_SUBSCRIBER_H_
 
+#include "base/gtest_prod_util.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/threading/thread_checker.h"
+#include "base/time/tick_clock.h"
 #include "media/cast/logging/logging_defines.h"
 #include "media/cast/logging/raw_event_subscriber.h"
+#include "media/cast/logging/receiver_time_offset_estimator.h"
+
+namespace base {
+class DictionaryValue;
+}
 
 namespace media {
 namespace cast {
 
+class StatsEventSubscriberTest;
+
 // A RawEventSubscriber implementation that subscribes to events,
 // and aggregates them into stats.
 class StatsEventSubscriber : public RawEventSubscriber {
  public:
-  StatsEventSubscriber(EventMediaType media_type);
+  StatsEventSubscriber(EventMediaType event_media_type,
+                       base::TickClock* clock,
+                       ReceiverTimeOffsetEstimator* offset_estimator);
 
   virtual ~StatsEventSubscriber();
 
@@ -24,19 +36,136 @@ class StatsEventSubscriber : public RawEventSubscriber {
   virtual void OnReceiveFrameEvent(const FrameEvent& frame_event) OVERRIDE;
   virtual void OnReceivePacketEvent(const PacketEvent& packet_event) OVERRIDE;
 
-  // Assigns |frame_stats_map| with frame stats.
-  void GetFrameStats(FrameStatsMap* frame_stats_map) const;
-
-  // Assigns |packet_stats_map| with packet stats.
-  void GetPacketStats(PacketStatsMap* packet_stats_map) const;
+  // Returns stats as a DictionaryValue. The dictionary contains one entry -
+  // "audio" or "video" pointing to an inner dictionary.
+  // The inner dictionary consists of string - double entries, where the string
+  // describes the name of the stat, and the double describes
+  // the value of the stat. See CastStat and StatsMap below.
+  scoped_ptr<base::DictionaryValue> GetStats() const;
 
-  // Resets all stats maps in this object.
+  // Resets stats in this object.
   void Reset();
 
  private:
-  EventMediaType event_media_type_;
+  friend class StatsEventSubscriberTest;
+  FRIEND_TEST_ALL_PREFIXES(StatsEventSubscriberTest, EmptyStats);
+  FRIEND_TEST_ALL_PREFIXES(StatsEventSubscriberTest, Capture);
+  FRIEND_TEST_ALL_PREFIXES(StatsEventSubscriberTest, Encode);
+  FRIEND_TEST_ALL_PREFIXES(StatsEventSubscriberTest, Decode);
+  FRIEND_TEST_ALL_PREFIXES(StatsEventSubscriberTest, PlayoutDelay);
+  FRIEND_TEST_ALL_PREFIXES(StatsEventSubscriberTest, E2ELatency);
+  FRIEND_TEST_ALL_PREFIXES(StatsEventSubscriberTest, Packets);
+
+  // Generic statistics given the raw data. More specific data (e.g. frame rate
+  // and bit rate) can be computed given the basic metrics.
+  // Some of the metrics will only be set when applicable, e.g. delay and size.
+  struct FrameLogStats {
+    FrameLogStats();
+    ~FrameLogStats();
+    int event_counter;
+    size_t sum_size;
+    base::TimeDelta sum_delay;
+  };
+
+  struct PacketLogStats {
+    PacketLogStats();
+    ~PacketLogStats();
+    int event_counter;
+    size_t sum_size;
+  };
+
+  enum CastStat {
+    // Capture frame rate.
+    CAPTURE_FPS,
+    // Encode frame rate.
+    ENCODE_FPS,
+    // Decode frame rate.
+    DECODE_FPS,
+    // Average encode duration in milliseconds.
+    // TODO(imcheng): This stat is not populated yet because we do not have
+    // the time when encode started. Record it in kVideoFrameEncoded event.
+    AVG_ENCODE_TIME_MS,
+    // Average playout delay in milliseconds, with target delay already
+    // accounted for. Ideally, every frame should have a playout delay of 0.
+    AVG_PLAYOUT_DELAY_MS,
+    // Duration from when a packet is transmitted to when it is received.
+    // This measures latency from sender to receiver.
+    AVG_NETWORK_LATENCY_MS,
+    // Duration from when a frame is captured to when it should be played out.
+    AVG_E2E_LATENCY_MS,
+    // Encode bitrate in kbps.
+    ENCODE_KBPS,
+    // Packet transmission bitrate in kbps.
+    TRANSMISSION_KBPS,
+    // Packet retransmission bitrate in kbps.
+    RETRANSMISSION_KBPS,
+    // Fraction of packet loss.
+    PACKET_LOSS_FRACTION,
+    // Duration in milliseconds since last receiver response.
+    MS_SINCE_LAST_RECEIVER_RESPONSE
+  };
+
+  typedef std::map<CastStat, double> StatsMap;
+  typedef std::map<RtpTimestamp, base::TimeTicks> FrameEventTimeMap;
+  typedef std::map<
+      std::pair<RtpTimestamp, uint16>,
+      std::pair<base::TimeTicks, CastLoggingEvent> >
+      PacketEventTimeMap;
+  typedef std::map<CastLoggingEvent, FrameLogStats> FrameStatsMap;
+  typedef std::map<CastLoggingEvent, PacketLogStats> PacketStatsMap;
+
+  static const char* CastStatToString(CastStat stat);
+
+  // Assigns |stats_map| with stats data. Used for testing.
+  void GetStatsInternal(StatsMap* stats_map) const;
+
+  bool GetReceiverOffset(base::TimeDelta* offset);
+  void RecordFrameCapturedTime(const FrameEvent& frame_event);
+  void RecordE2ELatency(const FrameEvent& frame_event);
+  void RecordPacketSentTime(const PacketEvent& packet_event);
+  void ErasePacketSentTime(const PacketEvent& packet_event);
+  void RecordNetworkLatency(const PacketEvent& packet_event);
+  void UpdateLastResponseTime(base::TimeTicks receiver_time);
+
+  void PopulateFpsStat(base::TimeTicks now,
+                       CastLoggingEvent event,
+                       CastStat stat,
+                       StatsMap* stats_map) const;
+  void PopulatePlayoutDelayStat(StatsMap* stats_map) const;
+  void PopulateFrameBitrateStat(base::TimeTicks now, StatsMap* stats_map) const;
+  void PopulatePacketBitrateStat(base::TimeTicks now,
+                                 CastLoggingEvent event,
+                                 CastStat stat,
+                                 StatsMap* stats_map) const;
+  void PopulatePacketLossPercentageStat(StatsMap* stats_map) const;
+
+  const EventMediaType event_media_type_;
+
+  // Not owned by this class.
+  base::TickClock* const clock_;
+
+  // Not owned by this class.
+  ReceiverTimeOffsetEstimator* const offset_estimator_;
+
   FrameStatsMap frame_stats_;
   PacketStatsMap packet_stats_;
+
+  base::TimeDelta total_network_latency_;
+  int network_latency_datapoints_;
+  base::TimeDelta total_e2e_latency_;
+  int e2e_latency_datapoints_;
+
+  base::TimeTicks last_response_received_time_;
+
+  // Fixed size map to record when recent frames were captured.
+  FrameEventTimeMap frame_captured_times_;
+
+  // Fixed size map to record when recent packets were sent.
+  PacketEventTimeMap packet_sent_times_;
+
+  // Sender time assigned on creation and |Reset()|.
+  base::TimeTicks start_time_;
+
   base::ThreadChecker thread_checker_;
   DISALLOW_COPY_AND_ASSIGN(StatsEventSubscriber);
 };
diff --git a/media/cast/logging/stats_event_subscriber_unittest.cc b/media/cast/logging/stats_event_subscriber_unittest.cc
index a532580f..7d6b5c8 100644
--- a/media/cast/logging/stats_event_subscriber_unittest.cc
+++ b/media/cast/logging/stats_event_subscriber_unittest.cc
@@ -4,147 +4,388 @@
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/rand_util.h"
 #include "base/test/simple_test_tick_clock.h"
 #include "base/time/tick_clock.h"
 #include "media/cast/cast_environment.h"
 #include "media/cast/logging/logging_defines.h"
 #include "media/cast/logging/stats_event_subscriber.h"
+#include "media/cast/test/fake_receiver_time_offset_estimator.h"
 #include "media/cast/test/fake_single_thread_task_runner.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+namespace {
+const int kReceiverOffsetSecs = 100;
+}
+
 namespace media {
 namespace cast {
 
 class StatsEventSubscriberTest : public ::testing::Test {
  protected:
   StatsEventSubscriberTest()
-      : testing_clock_(new base::SimpleTestTickClock()),
-        task_runner_(new test::FakeSingleThreadTaskRunner(testing_clock_)),
+      : sender_clock_(new base::SimpleTestTickClock()),
+        task_runner_(new test::FakeSingleThreadTaskRunner(sender_clock_)),
         cast_environment_(new CastEnvironment(
-            scoped_ptr<base::TickClock>(testing_clock_).Pass(),
+            scoped_ptr<base::TickClock>(sender_clock_).Pass(),
             task_runner_,
             task_runner_,
-            task_runner_)) {}
+            task_runner_)),
+        fake_offset_estimator_(
+            base::TimeDelta::FromSeconds(kReceiverOffsetSecs)) {
+    receiver_clock_.Advance(base::TimeDelta::FromSeconds(kReceiverOffsetSecs));
+    cast_environment_->Logging()->AddRawEventSubscriber(
+        &fake_offset_estimator_);
+  }
 
   virtual ~StatsEventSubscriberTest() {
     if (subscriber_.get())
       cast_environment_->Logging()->RemoveRawEventSubscriber(subscriber_.get());
+    cast_environment_->Logging()->RemoveRawEventSubscriber(
+        &fake_offset_estimator_);
+  }
+
+  void AdvanceClocks(base::TimeDelta delta) {
+    sender_clock_->Advance(delta);
+    receiver_clock_.Advance(delta);
   }
 
   void Init(EventMediaType event_media_type) {
     DCHECK(!subscriber_.get());
-    subscriber_.reset(new StatsEventSubscriber(event_media_type));
+    subscriber_.reset(new StatsEventSubscriber(
+        event_media_type, cast_environment_->Clock(), &fake_offset_estimator_));
     cast_environment_->Logging()->AddRawEventSubscriber(subscriber_.get());
   }
 
-  base::SimpleTestTickClock* testing_clock_;  // Owned by CastEnvironment.
+  base::SimpleTestTickClock* sender_clock_;  // Owned by CastEnvironment.
+  base::SimpleTestTickClock receiver_clock_;
   scoped_refptr<test::FakeSingleThreadTaskRunner> task_runner_;
   scoped_refptr<CastEnvironment> cast_environment_;
+  test::FakeReceiverTimeOffsetEstimator fake_offset_estimator_;
   scoped_ptr<StatsEventSubscriber> subscriber_;
 };
 
-TEST_F(StatsEventSubscriberTest, FrameStats) {
+TEST_F(StatsEventSubscriberTest, Capture) {
   Init(VIDEO_EVENT);
+
   uint32 rtp_timestamp = 0;
   uint32 frame_id = 0;
   int num_frames = 10;
-  int frame_size = 123;
-  int delay_base_ms = 10;
-  int target_bitrate = 1234;
-  base::TimeTicks now;
+  base::TimeTicks start_time = sender_clock_->NowTicks();
   for (int i = 0; i < num_frames; i++) {
-    now = testing_clock_->NowTicks();
-    cast_environment_->Logging()->InsertFrameEvent(
-        now, kVideoFrameReceived, rtp_timestamp, frame_id);
-    testing_clock_->Advance(base::TimeDelta::FromMilliseconds(30));
+    cast_environment_->Logging()->InsertFrameEvent(sender_clock_->NowTicks(),
+                                                   kVideoFrameCaptured,
+                                                   rtp_timestamp,
+                                                   frame_id);
+
+    AdvanceClocks(base::TimeDelta::FromMicroseconds(34567));
+    rtp_timestamp += 90;
+    frame_id++;
+  }
+
+  base::TimeTicks end_time = sender_clock_->NowTicks();
+
+  StatsEventSubscriber::StatsMap stats_map;
+  subscriber_->GetStatsInternal(&stats_map);
 
+  StatsEventSubscriber::StatsMap::iterator it =
+      stats_map.find(StatsEventSubscriber::CAPTURE_FPS);
+  ASSERT_NE(it, stats_map.end());
+
+  base::TimeDelta duration = end_time - start_time;
+  EXPECT_DOUBLE_EQ(
+      it->second,
+      static_cast<double>(num_frames) / duration.InMillisecondsF() * 1000);
+}
+
+TEST_F(StatsEventSubscriberTest, Encode) {
+  Init(VIDEO_EVENT);
+
+  uint32 rtp_timestamp = 0;
+  uint32 frame_id = 0;
+  int num_frames = 10;
+  base::TimeTicks start_time = sender_clock_->NowTicks();
+  int total_size = 0;
+  for (int i = 0; i < num_frames; i++) {
+    int size = 1000 + base::RandInt(-100, 100);
+    total_size += size;
     cast_environment_->Logging()->InsertEncodedFrameEvent(
-        now, kVideoFrameEncoded, rtp_timestamp, i, frame_size, true,
-        target_bitrate);
-    testing_clock_->Advance(base::TimeDelta::FromMilliseconds(30));
+        sender_clock_->NowTicks(),
+        kVideoFrameEncoded,
+        rtp_timestamp,
+        frame_id,
+        size,
+        true,
+        5678);
+
+    AdvanceClocks(base::TimeDelta::FromMicroseconds(35678));
+    rtp_timestamp += 90;
+    frame_id++;
+  }
+
+  base::TimeTicks end_time = sender_clock_->NowTicks();
+
+  StatsEventSubscriber::StatsMap stats_map;
+  subscriber_->GetStatsInternal(&stats_map);
+
+  StatsEventSubscriber::StatsMap::iterator it =
+      stats_map.find(StatsEventSubscriber::ENCODE_FPS);
+  ASSERT_NE(it, stats_map.end());
+
+  base::TimeDelta duration = end_time - start_time;
+  EXPECT_DOUBLE_EQ(
+      it->second,
+      static_cast<double>(num_frames) / duration.InMillisecondsF() * 1000);
+
+  it = stats_map.find(StatsEventSubscriber::ENCODE_KBPS);
+  ASSERT_NE(it, stats_map.end());
+
+  EXPECT_DOUBLE_EQ(it->second,
+              static_cast<double>(total_size) / duration.InMillisecondsF() * 8);
+}
+
+TEST_F(StatsEventSubscriberTest, Decode) {
+  Init(VIDEO_EVENT);
+
+  uint32 rtp_timestamp = 0;
+  uint32 frame_id = 0;
+  int num_frames = 10;
+  base::TimeTicks start_time = sender_clock_->NowTicks();
+  for (int i = 0; i < num_frames; i++) {
+    cast_environment_->Logging()->InsertFrameEvent(receiver_clock_.NowTicks(),
+                                                   kVideoFrameDecoded,
+                                                   rtp_timestamp,
+                                                   frame_id);
+
+    AdvanceClocks(base::TimeDelta::FromMicroseconds(36789));
+    rtp_timestamp += 90;
+    frame_id++;
+  }
+
+  base::TimeTicks end_time = sender_clock_->NowTicks();
+
+  StatsEventSubscriber::StatsMap stats_map;
+  subscriber_->GetStatsInternal(&stats_map);
+
+  StatsEventSubscriber::StatsMap::iterator it =
+      stats_map.find(StatsEventSubscriber::DECODE_FPS);
+  ASSERT_NE(it, stats_map.end());
 
+  base::TimeDelta duration = end_time - start_time;
+  EXPECT_DOUBLE_EQ(
+      it->second,
+      static_cast<double>(num_frames) / duration.InMillisecondsF() * 1000);
+}
+
+TEST_F(StatsEventSubscriberTest, PlayoutDelay) {
+  Init(VIDEO_EVENT);
+
+  uint32 rtp_timestamp = 0;
+  uint32 frame_id = 0;
+  int num_frames = 10;
+  int total_delay_ms = 0;
+  for (int i = 0; i < num_frames; i++) {
+    int delay_ms = base::RandInt(-50, 50);
+    base::TimeDelta delay = base::TimeDelta::FromMilliseconds(delay_ms);
+    total_delay_ms += delay_ms;
     cast_environment_->Logging()->InsertFrameEventWithDelay(
-        now,
+        receiver_clock_.NowTicks(),
         kVideoRenderDelay,
         rtp_timestamp,
-        i,
-        base::TimeDelta::FromMilliseconds(i * delay_base_ms));
-    testing_clock_->Advance(base::TimeDelta::FromMilliseconds(30));
+        frame_id,
+        delay);
 
+    AdvanceClocks(base::TimeDelta::FromMicroseconds(37890));
     rtp_timestamp += 90;
+    frame_id++;
   }
 
-  // Verify stats.
-  FrameStatsMap frame_stats;
-  subscriber_->GetFrameStats(&frame_stats);
+  StatsEventSubscriber::StatsMap stats_map;
+  subscriber_->GetStatsInternal(&stats_map);
+
+  StatsEventSubscriber::StatsMap::iterator it =
+      stats_map.find(StatsEventSubscriber::AVG_PLAYOUT_DELAY_MS);
+  ASSERT_NE(it, stats_map.end());
+
+  EXPECT_DOUBLE_EQ(
+      it->second, static_cast<double>(total_delay_ms) / num_frames);
+}
+
+TEST_F(StatsEventSubscriberTest, E2ELatency) {
+  Init(VIDEO_EVENT);
 
-  // Size of stats equals the number of events.
-  EXPECT_EQ(3u, frame_stats.size());
-  FrameStatsMap::const_iterator it = frame_stats.find(kVideoFrameReceived);
-  ASSERT_TRUE(it != frame_stats.end());
-  EXPECT_EQ(num_frames, it->second.event_counter);
+  uint32 rtp_timestamp = 0;
+  uint32 frame_id = 0;
+  int num_frames = 10;
+  base::TimeDelta total_latency;
+  for (int i = 0; i < num_frames; i++) {
+    cast_environment_->Logging()->InsertFrameEvent(sender_clock_->NowTicks(),
+                                                   kVideoFrameCaptured,
+                                                   rtp_timestamp,
+                                                   frame_id);
+
+    int latency_micros = 100000 + base::RandInt(-5000, 50000);
+    base::TimeDelta latency = base::TimeDelta::FromMicroseconds(latency_micros);
+    AdvanceClocks(latency);
+
+    int delay_micros = base::RandInt(-50000, 50000);
+    base::TimeDelta delay = base::TimeDelta::FromMilliseconds(delay_micros);
+    total_latency += latency + delay;
+
+    cast_environment_->Logging()->InsertFrameEventWithDelay(
+        receiver_clock_.NowTicks(),
+        kVideoRenderDelay,
+        rtp_timestamp,
+        frame_id,
+        delay);
 
-  it = frame_stats.find(kVideoFrameEncoded);
-  ASSERT_TRUE(it != frame_stats.end());
+    rtp_timestamp += 90;
+    frame_id++;
+  }
 
-  EXPECT_EQ(num_frames * frame_size, static_cast<int>(it->second.sum_size));
+  StatsEventSubscriber::StatsMap stats_map;
+  subscriber_->GetStatsInternal(&stats_map);
 
-  it = frame_stats.find(kVideoRenderDelay);
-  ASSERT_TRUE(it != frame_stats.end());
+  StatsEventSubscriber::StatsMap::iterator it =
+      stats_map.find(StatsEventSubscriber::AVG_E2E_LATENCY_MS);
+  ASSERT_NE(it, stats_map.end());
 
-  EXPECT_EQ(0, it->second.min_delay.InMilliseconds());
-  EXPECT_EQ((num_frames - 1) * delay_base_ms,
-            it->second.max_delay.InMilliseconds());
-  EXPECT_EQ((num_frames - 1) * num_frames / 2 * delay_base_ms,
-            it->second.sum_delay.InMilliseconds());
+  EXPECT_DOUBLE_EQ(
+      it->second, total_latency.InMillisecondsF() / num_frames);
 }
 
-TEST_F(StatsEventSubscriberTest, PacketStats) {
-  Init(AUDIO_EVENT);
+TEST_F(StatsEventSubscriberTest, Packets) {
+  Init(VIDEO_EVENT);
+
   uint32 rtp_timestamp = 0;
-  uint32 frame_id = 0;
   int num_packets = 10;
-  int packet_size = 123;
-  base::TimeTicks first_event_time = testing_clock_->NowTicks();
-  base::TimeTicks now;
+  int num_latency_recorded_packets = 0;
+  base::TimeTicks start_time = sender_clock_->NowTicks();
+  int total_size = 0;
+  int retransmit_total_size = 0;
+  base::TimeDelta total_latency;
+  int num_packets_sent = 0;
+  int num_packets_retransmitted = 0;
+  // Every 2nd packet will be retransmitted once.
+  // Every 4th packet will be retransmitted twice.
+  // Every 8th packet will be retransmitted 3 times.
   for (int i = 0; i < num_packets; i++) {
-    now = testing_clock_->NowTicks();
-    cast_environment_->Logging()->InsertPacketEvent(now,
-                                                    kAudioPacketSentToPacer,
+    int size = 1000 + base::RandInt(-100, 100);
+    total_size += size;
+
+    cast_environment_->Logging()->InsertPacketEvent(sender_clock_->NowTicks(),
+                                                    kVideoPacketSentToNetwork,
+                                                    rtp_timestamp,
+                                                    0,
+                                                    i,
+                                                    num_packets - 1,
+                                                    size);
+    num_packets_sent++;
+
+    int latency_micros = 20000 + base::RandInt(-10000, 10000);
+    base::TimeDelta latency = base::TimeDelta::FromMicroseconds(latency_micros);
+    // Latency is only recorded for packets that aren't retransmitted.
+    if (i % 2 != 0) {
+      total_latency += latency;
+      num_latency_recorded_packets++;
+    }
+
+    AdvanceClocks(latency);
+
+    base::TimeTicks received_time = receiver_clock_.NowTicks();
+
+    // Retransmission 1.
+    AdvanceClocks(base::TimeDelta::FromMicroseconds(12345));
+    if (i % 2 == 0) {
+      cast_environment_->Logging()->InsertPacketEvent(
+          receiver_clock_.NowTicks(),
+          kVideoPacketRetransmitted,
+          rtp_timestamp,
+          0,
+          i,
+          num_packets - 1,
+          size);
+      retransmit_total_size += size;
+      num_packets_sent++;
+      num_packets_retransmitted++;
+    }
+
+    // Retransmission 2.
+    AdvanceClocks(base::TimeDelta::FromMicroseconds(13456));
+    if (i % 4 == 0) {
+      cast_environment_->Logging()->InsertPacketEvent(
+          receiver_clock_.NowTicks(),
+          kVideoPacketRetransmitted,
+          rtp_timestamp,
+          0,
+          i,
+          num_packets - 1,
+          size);
+      retransmit_total_size += size;
+      num_packets_sent++;
+      num_packets_retransmitted++;
+    }
+
+    // Retransmission 3.
+    AdvanceClocks(base::TimeDelta::FromMicroseconds(14567));
+    if (i % 8 == 0) {
+      cast_environment_->Logging()->InsertPacketEvent(
+          receiver_clock_.NowTicks(),
+          kVideoPacketRetransmitted,
+          rtp_timestamp,
+          0,
+          i,
+          num_packets - 1,
+          size);
+      retransmit_total_size += size;
+      num_packets_sent++;
+      num_packets_retransmitted++;
+    }
+
+    cast_environment_->Logging()->InsertPacketEvent(received_time,
+                                                    kVideoPacketReceived,
                                                     rtp_timestamp,
-                                                    frame_id,
                                                     0,
-                                                    10,
-                                                    packet_size);
-    testing_clock_->Advance(base::TimeDelta::FromMilliseconds(30));
+                                                    i,
+                                                    num_packets - 1,
+                                                    size);
   }
 
-  PacketStatsMap stats_map;
-  subscriber_->GetPacketStats(&stats_map);
+  base::TimeTicks end_time = sender_clock_->NowTicks();
+  base::TimeDelta duration = end_time - start_time;
 
-  // Size of stats equals the number of event types.
-  EXPECT_EQ(1u, stats_map.size());
-  PacketStatsMap::const_iterator it = stats_map.find(kAudioPacketSentToPacer);
-  ASSERT_NE(stats_map.end(), it);
+  StatsEventSubscriber::StatsMap stats_map;
+  subscriber_->GetStatsInternal(&stats_map);
 
-  EXPECT_EQ(first_event_time, it->second.first_event_time);
-  EXPECT_EQ(now, it->second.last_event_time);
-  EXPECT_EQ(num_packets, it->second.event_counter);
-  EXPECT_EQ(num_packets * packet_size, static_cast<int>(it->second.sum_size));
-}
+  // Measure AVG_NETWORK_LATENCY_MS, TRANSMISSION_KBPS, RETRANSMISSION_KBPS,
+  // and PACKET_LOSS_FRACTION.
+  StatsEventSubscriber::StatsMap::iterator it =
+      stats_map.find(StatsEventSubscriber::AVG_NETWORK_LATENCY_MS);
+  ASSERT_NE(it, stats_map.end());
 
-TEST_F(StatsEventSubscriberTest, Reset) {
-  Init(VIDEO_EVENT);
-  cast_environment_->Logging()->InsertFrameEvent(
-      testing_clock_->NowTicks(), kVideoFrameReceived, 0, 0);
+  EXPECT_DOUBLE_EQ(
+      it->second,
+      total_latency.InMillisecondsF() / num_latency_recorded_packets);
+
+  it = stats_map.find(StatsEventSubscriber::TRANSMISSION_KBPS);
+  ASSERT_NE(it, stats_map.end());
+
+  EXPECT_DOUBLE_EQ(it->second,
+              static_cast<double>(total_size) / duration.InMillisecondsF() * 8);
+
+  it = stats_map.find(StatsEventSubscriber::RETRANSMISSION_KBPS);
+  ASSERT_NE(it, stats_map.end());
+
+  EXPECT_DOUBLE_EQ(it->second,
+              static_cast<double>(retransmit_total_size) /
+                  duration.InMillisecondsF() * 8);
 
-  FrameStatsMap frame_stats;
-  subscriber_->GetFrameStats(&frame_stats);
-  EXPECT_EQ(1u, frame_stats.size());
+  it = stats_map.find(StatsEventSubscriber::PACKET_LOSS_FRACTION);
+  ASSERT_NE(it, stats_map.end());
 
-  subscriber_->Reset();
-  subscriber_->GetFrameStats(&frame_stats);
-  EXPECT_TRUE(frame_stats.empty());
+  EXPECT_DOUBLE_EQ(
+      it->second,
+      static_cast<double>(num_packets_retransmitted) / num_packets_sent);
 }
 
 }  // namespace cast
diff --git a/media/cast/logging/stats_util.cc b/media/cast/logging/stats_util.cc
deleted file mode 100644
index 9b50b5d..0000000
--- a/media/cast/logging/stats_util.cc
+++ /dev/null
@@ -1,72 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "media/cast/logging/stats_util.h"
-
-#include "base/logging.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/values.h"
-
-namespace media {
-namespace cast {
-
-scoped_ptr<base::DictionaryValue> ConvertStats(
-    const FrameStatsMap& frame_stats_map,
-    const PacketStatsMap& packet_stats_map) {
-  scoped_ptr<base::DictionaryValue> overall_stats(new base::DictionaryValue);
-
-  scoped_ptr<base::DictionaryValue> overall_frame_stats(
-      new base::DictionaryValue);
-  for (FrameStatsMap::const_iterator it = frame_stats_map.begin();
-       it != frame_stats_map.end();
-       ++it) {
-    scoped_ptr<base::DictionaryValue> frame_stats(new base::DictionaryValue);
-
-    frame_stats->SetDouble("firstEventTime",
-                           it->second.first_event_time.ToInternalValue());
-    frame_stats->SetDouble("lastEventTime",
-                           it->second.last_event_time.ToInternalValue());
-    frame_stats->SetInteger("count", it->second.event_counter);
-    frame_stats->SetInteger("sizeTotal", static_cast<int>(it->second.sum_size));
-    frame_stats->SetInteger("minDelayMs",
-                            it->second.min_delay.InMilliseconds());
-    frame_stats->SetInteger("maxDelayMs",
-                            it->second.max_delay.InMilliseconds());
-    frame_stats->SetInteger("sumDelayMs",
-                            it->second.sum_delay.InMilliseconds());
-
-    overall_frame_stats->Set(CastLoggingToString(it->first),
-                             frame_stats.release());
-  }
-
-  overall_stats->Set("frameStats", overall_frame_stats.release());
-
-  scoped_ptr<base::DictionaryValue> overall_packet_stats(
-      new base::DictionaryValue);
-  for (PacketStatsMap::const_iterator it = packet_stats_map.begin();
-       it != packet_stats_map.end();
-       ++it) {
-    scoped_ptr<base::DictionaryValue> packet_stats(new base::DictionaryValue);
-
-    packet_stats->SetDouble("firstEventTime",
-                            it->second.first_event_time.ToInternalValue());
-    packet_stats->SetDouble("lastEventTime",
-                            it->second.last_event_time.ToInternalValue());
-    packet_stats->SetDouble("lastEventTime",
-                            it->second.last_event_time.ToInternalValue());
-    packet_stats->SetInteger("count", it->second.event_counter);
-    packet_stats->SetInteger("sizeTotal",
-                             static_cast<int>(it->second.sum_size));
-
-    overall_packet_stats->Set(CastLoggingToString(it->first),
-                              packet_stats.release());
-  }
-
-  overall_stats->Set("packetStats", overall_packet_stats.release());
-
-  return overall_stats.Pass();
-}
-
-}  // namespace cast
-}  // namespace media
diff --git a/media/cast/logging/stats_util.h b/media/cast/logging/stats_util.h
deleted file mode 100644
index bbac273..0000000
--- a/media/cast/logging/stats_util.h
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef MEDIA_CAST_LOGGING_STATS_UTIL_H_
-#define MEDIA_CAST_LOGGING_STATS_UTIL_H_
-
-#include "base/memory/scoped_ptr.h"
-#include "media/cast/logging/logging_defines.h"
-
-namespace base {
-class DictionaryValue;
-}
-
-namespace media {
-namespace cast {
-
-// Converts stats provided in |frame_stats_map| and |packet_stats_map| to
-// base::DictionaryValue format. See .cc file for the exact structure.
-scoped_ptr<base::DictionaryValue> ConvertStats(
-    const FrameStatsMap& frame_stats_map,
-    const PacketStatsMap& packet_stats_map);
-
-}  // namespace cast
-}  // namespace media
-
-#endif  // MEDIA_CAST_LOGGING_STATS_UTIL_H_
diff --git a/media/cast/test/fake_receiver_time_offset_estimator.cc b/media/cast/test/fake_receiver_time_offset_estimator.cc
new file mode 100644
index 0000000..3cc5f72
--- /dev/null
+++ b/media/cast/test/fake_receiver_time_offset_estimator.cc
@@ -0,0 +1,37 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/cast/test/fake_receiver_time_offset_estimator.h"
+
+namespace media {
+namespace cast {
+namespace test {
+
+FakeReceiverTimeOffsetEstimator::FakeReceiverTimeOffsetEstimator(
+    base::TimeDelta offset)
+    : offset_(offset) {}
+
+FakeReceiverTimeOffsetEstimator::~FakeReceiverTimeOffsetEstimator() {}
+
+void FakeReceiverTimeOffsetEstimator::OnReceiveFrameEvent(
+    const FrameEvent& frame_event) {
+  // Do nothing.
+}
+
+void FakeReceiverTimeOffsetEstimator::OnReceivePacketEvent(
+    const PacketEvent& packet_event) {
+  // Do nothing.
+}
+
+bool FakeReceiverTimeOffsetEstimator::GetReceiverOffsetBounds(
+    base::TimeDelta* lower_bound,
+    base::TimeDelta* upper_bound) {
+  *lower_bound = offset_;
+  *upper_bound = offset_;
+  return true;
+}
+
+}  // namespace test
+}  // namespace cast
+}  // namespace media
diff --git a/media/cast/test/fake_receiver_time_offset_estimator.h b/media/cast/test/fake_receiver_time_offset_estimator.h
new file mode 100644
index 0000000..2a4d3cd
--- /dev/null
+++ b/media/cast/test/fake_receiver_time_offset_estimator.h
@@ -0,0 +1,42 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MEDIA_CAST_TEST_FAKE_RECEIVER_TIME_OFFSET_ESTIMATOR_H_
+#define MEDIA_CAST_TEST_FAKE_RECEIVER_TIME_OFFSET_ESTIMATOR_H_
+
+#include "base/time/time.h"
+#include "base/threading/thread_checker.h"
+#include "media/cast/logging/logging_defines.h"
+#include "media/cast/logging/receiver_time_offset_estimator.h"
+
+namespace media {
+namespace cast {
+namespace test {
+
+// This class is used for testing. It will always return the |offset| value
+// provided during construction as offset bounds.
+class FakeReceiverTimeOffsetEstimator : public ReceiverTimeOffsetEstimator {
+ public:
+  FakeReceiverTimeOffsetEstimator(base::TimeDelta offset);
+
+  virtual ~FakeReceiverTimeOffsetEstimator();
+
+  // RawReventSubscriber implementations.
+  virtual void OnReceiveFrameEvent(const FrameEvent& frame_event) OVERRIDE;
+  virtual void OnReceivePacketEvent(const PacketEvent& packet_event) OVERRIDE;
+
+  // ReceiverTimeOffsetEstimator
+  virtual bool GetReceiverOffsetBounds(base::TimeDelta* lower_bound,
+                                       base::TimeDelta* upper_bound) OVERRIDE;
+
+ private:
+  const base::TimeDelta offset_;
+  DISALLOW_COPY_AND_ASSIGN(FakeReceiverTimeOffsetEstimator);
+};
+
+}  // namespace test
+}  // namespace cast
+}  // namespace media
+
+#endif  // MEDIA_CAST_TEST_FAKE_RECEIVER_TIME_OFFSET_ESTIMATOR_H_
diff --git a/media/cast/test/sender.cc b/media/cast/test/sender.cc
index 628f6b7..4a30ea9 100644
--- a/media/cast/test/sender.cc
+++ b/media/cast/test/sender.cc
@@ -14,12 +14,14 @@
 #include "base/files/file_path.h"
 #include "base/files/memory_mapped_file.h"
 #include "base/files/scoped_file.h"
+#include "base/json/json_writer.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/threading/thread.h"
 #include "base/time/default_tick_clock.h"
+#include "base/values.h"
 #include "media/audio/audio_parameters.h"
 #include "media/base/audio_buffer.h"
 #include "media/base/audio_bus.h"
@@ -36,6 +38,8 @@
 #include "media/cast/logging/log_serializer.h"
 #include "media/cast/logging/logging_defines.h"
 #include "media/cast/logging/proto/raw_events.pb.h"
+#include "media/cast/logging/receiver_time_offset_estimator_impl.h"
+#include "media/cast/logging/stats_event_subscriber.h"
 #include "media/cast/test/utility/audio_utility.h"
 #include "media/cast/test/utility/default_config.h"
 #include "media/cast/test/utility/input_builder.h"
@@ -801,7 +805,7 @@ void DumpLoggingData(const media::cast::proto::LogMetadata& log_metadata,
     VLOG(0) << "Failed to write logs to file.";
 }
 
-void WriteLogsToFileAndStopSubscribing(
+void WriteLogsToFileAndDestroySubscribers(
     const scoped_refptr<media::cast::CastEnvironment>& cast_environment,
     scoped_ptr<media::cast::EncodingEventSubscriber> video_event_subscriber,
     scoped_ptr<media::cast::EncodingEventSubscriber> audio_event_subscriber,
@@ -834,6 +838,30 @@ void WriteLogsToFileAndStopSubscribing(
                   audio_log_file.Pass());
 }
 
+void WriteStatsAndDestroySubscribers(
+    const scoped_refptr<media::cast::CastEnvironment>& cast_environment,
+    scoped_ptr<media::cast::StatsEventSubscriber> video_event_subscriber,
+    scoped_ptr<media::cast::StatsEventSubscriber> audio_event_subscriber,
+    scoped_ptr<media::cast::ReceiverTimeOffsetEstimatorImpl> estimator) {
+  cast_environment->Logging()->RemoveRawEventSubscriber(
+      video_event_subscriber.get());
+  cast_environment->Logging()->RemoveRawEventSubscriber(
+      audio_event_subscriber.get());
+  cast_environment->Logging()->RemoveRawEventSubscriber(estimator.get());
+
+  scoped_ptr<base::DictionaryValue> stats = video_event_subscriber->GetStats();
+  std::string json;
+  base::JSONWriter::WriteWithOptions(
+      stats.get(), base::JSONWriter::OPTIONS_PRETTY_PRINT, &json);
+  VLOG(0) << "Video stats: " << json;
+
+  stats = audio_event_subscriber->GetStats();
+  json.clear();
+  base::JSONWriter::WriteWithOptions(
+      stats.get(), base::JSONWriter::OPTIONS_PRETTY_PRINT, &json);
+  VLOG(0) << "Audio stats: " << json;
+}
+
 }  // namespace
 
 int main(int argc, char** argv) {
@@ -942,6 +970,23 @@ int main(int argc, char** argv) {
   cast_environment->Logging()->AddRawEventSubscriber(
       audio_event_subscriber.get());
 
+  // Subscribers for stats.
+  scoped_ptr<media::cast::ReceiverTimeOffsetEstimatorImpl> offset_estimator(
+      new media::cast::ReceiverTimeOffsetEstimatorImpl);
+  cast_environment->Logging()->AddRawEventSubscriber(offset_estimator.get());
+  scoped_ptr<media::cast::StatsEventSubscriber> video_stats_subscriber(
+      new media::cast::StatsEventSubscriber(media::cast::VIDEO_EVENT,
+                                            cast_environment->Clock(),
+                                            offset_estimator.get()));
+  scoped_ptr<media::cast::StatsEventSubscriber> audio_stats_subscriber(
+      new media::cast::StatsEventSubscriber(media::cast::AUDIO_EVENT,
+                                            cast_environment->Clock(),
+                                            offset_estimator.get()));
+  cast_environment->Logging()->AddRawEventSubscriber(
+      video_stats_subscriber.get());
+  cast_environment->Logging()->AddRawEventSubscriber(
+      audio_stats_subscriber.get());
+
   base::ScopedFILE video_log_file(fopen(video_log_file_name.c_str(), "w"));
   if (!video_log_file) {
     VLOG(1) << "Failed to open video log file for writing.";
@@ -954,18 +999,29 @@ int main(int argc, char** argv) {
     exit(-1);
   }
 
-  const int logging_duration_seconds = 300;
+  const int logging_duration_seconds = 10;
   io_message_loop.message_loop_proxy()->PostDelayedTask(
       FROM_HERE,
-      base::Bind(&WriteLogsToFileAndStopSubscribing,
+      base::Bind(&WriteLogsToFileAndDestroySubscribers,
                  cast_environment,
                  base::Passed(&video_event_subscriber),
                  base::Passed(&audio_event_subscriber),
                  base::Passed(&video_log_file),
                  base::Passed(&audio_log_file)),
       base::TimeDelta::FromSeconds(logging_duration_seconds));
+
+  io_message_loop.message_loop_proxy()->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(&WriteStatsAndDestroySubscribers,
+                 cast_environment,
+                 base::Passed(&video_stats_subscriber),
+                 base::Passed(&audio_stats_subscriber),
+                 base::Passed(&offset_estimator)),
+      base::TimeDelta::FromSeconds(logging_duration_seconds));
+
   send_process->Start(cast_sender->audio_frame_input(),
                       cast_sender->video_frame_input());
+
   io_message_loop.Run();
   return 0;
 }