Add ability to handle data from multiple streams in RateAccCounter.

webrtc/video/stats_counter.cc

Index: webrtc/video/stats_counter.cc
diff --git a/webrtc/video/stats_counter.cc b/webrtc/video/stats_counter.cc
index 42d23adcfc60f71015e690090c8d779e47959421..584d79a8017140e003a0a8c37bd0b852f53a2667 100644
--- a/webrtc/video/stats_counter.cc
+++ b/webrtc/video/stats_counter.cc
@@ -19,6 +19,47 @@ namespace webrtc {
 namespace {
 // Periodic time interval for processing samples.
 const int64_t kProcessIntervalMs = 2000;
+
+int64_t Num(const std::map<uint32_t, StatsCounter::Samples>& samples) {
+  int64_t num = 0;
+  for (const auto& it : samples)
+    num += it.second.num_;
+  return num;
+}
+
+int64_t Sum(const std::map<uint32_t, StatsCounter::Samples>& samples) {
+  int64_t sum = 0;
+  for (const auto& it : samples)
+    sum += it.second.sum_;
+  return sum;
+}
+
+int Max(const std::map<uint32_t, StatsCounter::Samples>& samples) {
+  int max = std::numeric_limits<int>::min();
+  for (const auto& it : samples)
+    max = std::max(it.second.max_, max);
+  return max;
+}
+
+void Reset(std::map<uint32_t, StatsCounter::Samples>* samples) {
+  for (auto& it : *samples)
+    it.second.Reset();
+}
+
+int64_t Diff(const std::map<uint32_t, StatsCounter::Samples>& samples) {
+  int64_t sum_diff = 0;
+  int num = 0;
+  for (const auto& it : samples) {
+    if (it.second.num_ > 0) {
+      int64_t diff = it.second.sum_ - it.second.last_sum_;
+      if (diff >= 0) {
+        sum_diff += diff;
+        ++num;
+      }
+    }
+  }
+  return (num > 0) ? sum_diff : -1;
+}
 }  // namespace
 
 // Class holding periodically computed metrics.
@@ -54,16 +95,32 @@ class AggregatedCounter {
   AggregatedStats stats_;
 };
 
+// Gathered samples within a process interval.
+void StatsCounter::Samples::Add(int sample) {
+  sum_ += sample;
+  ++num_;
+  max_ = std::max(sample, max_);
+}
+
+void StatsCounter::Samples::Set(int sample) {
+  sum_ = sample;
+  ++num_;
+}
+
+void StatsCounter::Samples::Reset() {
+  if (num_ > 0)
+    last_sum_ = sum_;
+  sum_ = 0;
+  num_ = 0;
+  max_ = std::numeric_limits<int>::min();
+}
+
 // StatsCounter class.
 StatsCounter::StatsCounter(Clock* clock,
                            bool include_empty_intervals,
                            StatsCounterObserver* observer)
-    : max_(0),
-      sum_(0),
-      num_samples_(0),
-      last_sum_(0),
+    : include_empty_intervals_(include_empty_intervals),
       clock_(clock),
-      include_empty_intervals_(include_empty_intervals),
       observer_(observer),
       aggregated_counter_(new AggregatedCounter()),
       last_process_time_ms_(-1) {}
@@ -98,20 +155,14 @@ bool StatsCounter::TimeToProcess() {
   return true;
 }
 
-void StatsCounter::Set(int sample) {
+void StatsCounter::Set(int sample, uint32_t ssrc) {
   TryProcess();
-  ++num_samples_;
-  sum_ = sample;
+  samples_[ssrc].Set(sample);
 }
 
 void StatsCounter::Add(int sample) {
   TryProcess();
-  ++num_samples_;
-  sum_ += sample;
-
-  if (num_samples_ == 1)
-    max_ = sample;
-  max_ = std::max(sample, max_);
+  samples_[0].Add(sample);

[stefan-webrtc, 2016/08/19 14:36:56]

Is zero some default ssrc? I think it's also a valid ssrc, so I don't think
using it as default is safe?

[åsapersson, 2016/08/23 09:06:02]

The ssrc can only be set for RateAccCounter (and not for the other counters) so
just set to something here (i.e. 0).

[stefan-webrtc, 2016/09/08 07:13:34]

Acknowledged.

 }
 
 void StatsCounter::TryProcess() {
@@ -124,10 +175,8 @@ void StatsCounter::TryProcess() {
     if (observer_)
       observer_->OnMetricUpdated(metric);
   }
-  last_sum_ = sum_;
-  sum_ = 0;
-  max_ = 0;
-  num_samples_ = 0;
+
+  Reset(&samples_);
 }
 
 // StatsCounter sub-classes.
@@ -141,9 +190,11 @@ void AvgCounter::Add(int sample) {
 }
 
 bool AvgCounter::GetMetric(int* metric) const {
-  if (num_samples_ == 0)
+  int64_t num = Num(samples_);
+  if (num == 0)
     return false;
-  *metric = (sum_ + num_samples_ / 2) / num_samples_;
+
+  *metric = (Sum(samples_) + num / 2) / num;
   return true;
 }
 
@@ -157,9 +208,11 @@ void MaxCounter::Add(int sample) {
 }
 
 bool MaxCounter::GetMetric(int* metric) const {
-  if (num_samples_ == 0)
+  int64_t num = Num(samples_);
+  if (num == 0)
     return false;
-  *metric = max_;
+
+  *metric = Max(samples_);
   return true;
 }
 
@@ -173,9 +226,11 @@ void PercentCounter::Add(bool sample) {
 }
 
 bool PercentCounter::GetMetric(int* metric) const {
-  if (num_samples_ == 0)
+  int64_t num = Num(samples_);
+  if (num == 0)
     return false;
-  *metric = (sum_ * 100 + num_samples_ / 2) / num_samples_;
+
+  *metric = (Sum(samples_) * 100 + num / 2) / num;
   return true;
 }
 
@@ -189,9 +244,11 @@ void PermilleCounter::Add(bool sample) {
 }
 
 bool PermilleCounter::GetMetric(int* metric) const {
-  if (num_samples_ == 0)
+  int64_t num = Num(samples_);
+  if (num == 0)
     return false;
-  *metric = (sum_ * 1000 + num_samples_ / 2) / num_samples_;
+
+  *metric = (Sum(samples_) * 1000 + num / 2) / num;
   return true;
 }
 
@@ -205,9 +262,11 @@ void RateCounter::Add(int sample) {
 }
 
 bool RateCounter::GetMetric(int* metric) const {
-  if (num_samples_ == 0)
+  if (Num(samples_) == 0)
     return false;
-  *metric = (sum_ * 1000 + kProcessIntervalMs / 2) / kProcessIntervalMs;
+
+  *metric =
+      (Sum(samples_) * 1000 + kProcessIntervalMs / 2) / kProcessIntervalMs;
   return true;
 }
 
@@ -216,15 +275,19 @@ RateAccCounter::RateAccCounter(Clock* clock,
                                bool include_empty_intervals)
     : StatsCounter(clock, include_empty_intervals, observer) {}
 
-void RateAccCounter::Set(int sample) {
-  StatsCounter::Set(sample);
+void RateAccCounter::Set(int sample, uint32_t ssrc) {
+  StatsCounter::Set(sample, ssrc);
 }
 
 bool RateAccCounter::GetMetric(int* metric) const {
-  if (num_samples_ == 0 || last_sum_ > sum_)
+  if (Num(samples_) == 0)
     return false;
-  *metric =
-      ((sum_ - last_sum_) * 1000 + kProcessIntervalMs / 2) / kProcessIntervalMs;
+
+  int64_t diff = Diff(samples_);
+  if (diff < 0 || (!include_empty_intervals_ && diff == 0))
+    return false;
+
+  *metric = (diff * 1000 + kProcessIntervalMs / 2) / kProcessIntervalMs;
   return true;
 }