NetEq: Implement Average Excess Buffer Delay stats

webrtc/modules/audio_coding/neteq/statistics_calculator.cc

Index: webrtc/modules/audio_coding/neteq/statistics_calculator.cc
diff --git a/webrtc/modules/audio_coding/neteq/statistics_calculator.cc b/webrtc/modules/audio_coding/neteq/statistics_calculator.cc
index dd63c122253a6912bd69431dc43108353f90cf90..b4d6a6c1dec8b7c3bb3ec907e97b102376211614 100644
--- a/webrtc/modules/audio_coding/neteq/statistics_calculator.cc
+++ b/webrtc/modules/audio_coding/neteq/statistics_calculator.cc
@@ -43,6 +43,32 @@ void StatisticsCalculator::DelayedPacketOutagesPerMinuteCounter::LogToUma()
                            counter_);
 }
 
+void StatisticsCalculator::AverageExcessBufferDelayMs::
+    RegisterPacketWaitingTime(int time_ms) {
+  sum_ += time_ms;
+  ++num_packets_;
+}
+
+void StatisticsCalculator::AverageExcessBufferDelayMs::AdvanceClock(
+    int step_ms) {
+  timer_ += step_ms;
+  if (timer_ < kReportIntervalMs) {
+    return;
+  }
+  LogToUma();
+  sum_ = 0.0;
+  num_packets_ = 0;
+  timer_ -= kReportIntervalMs;
+  DCHECK_GE(timer_, 0);
+}
+
+void StatisticsCalculator::AverageExcessBufferDelayMs::LogToUma() {
+  if (num_packets_ > 0) {
+    RTC_HISTOGRAM_COUNTS_1000("WebRTC.Audio.AverageExcessBufferDelayMs",
+                              static_cast<int>(sum_ / num_packets_));
+  }
+}
+
 StatisticsCalculator::StatisticsCalculator()
     : preemptive_samples_(0),
       accelerate_samples_(0),
@@ -108,8 +134,9 @@ void StatisticsCalculator::LostSamples(int num_samples) {
 }
 
 void StatisticsCalculator::IncreaseCounter(int num_samples, int fs_hz) {
-  delayed_packet_outage_counter_.AdvanceClock(
-      rtc::CheckedDivExact(1000 * num_samples, fs_hz));
+  const int time_step_ms = rtc::CheckedDivExact(1000 * num_samples, fs_hz);
+  delayed_packet_outage_counter_.AdvanceClock(time_step_ms);
+  excess_buffer_delay_.AdvanceClock(time_step_ms);
   timestamps_since_last_report_ += static_cast<uint32_t>(num_samples);
   if (timestamps_since_last_report_ >
       static_cast<uint32_t>(fs_hz * kMaxReportPeriod)) {
@@ -131,6 +158,7 @@ void StatisticsCalculator::LogDelayedPacketOutageEvent(int outage_duration_ms) {
 }
 
 void StatisticsCalculator::StoreWaitingTime(int waiting_time_ms) {
+  excess_buffer_delay_.RegisterPacketWaitingTime(waiting_time_ms);
   assert(next_waiting_time_index_ < kLenWaitingTimes);
   waiting_times_[next_waiting_time_index_] = waiting_time_ms;
   next_waiting_time_index_++;