video/stats_counter.cc - src/webrtc - Git at Google

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */

 #include "webrtc/video/stats_counter.h"

 #include <algorithm>
 #include <limits>
 #include <map>

 #include "webrtc/base/checks.h"
 #include "webrtc/system_wrappers/include/clock.h"

 namespace webrtc {

 namespace {
 // Default periodic time interval for processing samples.
 const int64_t kDefaultProcessIntervalMs = 2000;
 const uint32_t kStreamId0 = 0;
 }  // namespace

 std::string AggregatedStats::ToString() const {
   return ToStringWithMultiplier(1);
 }

 std::string AggregatedStats::ToStringWithMultiplier(int multiplier) const {
   std::stringstream ss;
   ss << "periodic_samples:" << num_samples << ", {";
   ss << "min:" << (min * multiplier) << ", ";
   ss << "avg:" << (average * multiplier) << ", ";
   ss << "max:" << (max * multiplier) << "}";
   return ss.str();
 }

 // Class holding periodically computed metrics.
 class AggregatedCounter {
  public:
   AggregatedCounter() : last_sample_(0), sum_samples_(0) {}
   ~AggregatedCounter() {}

   void Add(int sample) {
     last_sample_ = sample;
     sum_samples_ += sample;
     ++stats_.num_samples;
     if (stats_.num_samples == 1) {
       stats_.min = sample;
       stats_.max = sample;
     }
     stats_.min = std::min(sample, stats_.min);
     stats_.max = std::max(sample, stats_.max);
   }

   AggregatedStats ComputeStats() {
     Compute();
     return stats_;
   }

   bool Empty() const { return stats_.num_samples == 0; }

   int last_sample() const { return last_sample_; }

  private:
   void Compute() {
     if (stats_.num_samples == 0)
       return;

     stats_.average =
         (sum_samples_ + stats_.num_samples / 2) / stats_.num_samples;
   }
   int last_sample_;
   int64_t sum_samples_;
   AggregatedStats stats_;
 };

 // Class holding gathered samples within a process interval.
 class Samples {
  public:
   Samples() : total_count_(0) {}
   ~Samples() {}

   void Add(int sample, uint32_t stream_id) {
     samples_[stream_id].Add(sample);
     ++total_count_;
   }
   void Set(int sample, uint32_t stream_id) {
     samples_[stream_id].Set(sample);
     ++total_count_;
   }

   int64_t Count() const { return total_count_; }
   bool Empty() const { return total_count_ == 0; }

   int64_t Sum() const {
     int64_t sum = 0;
     for (const auto& it : samples_)
       sum += it.second.sum_;
     return sum;
   }

   int Max() const {
     int max = std::numeric_limits<int>::min();
     for (const auto& it : samples_)
       max = std::max(it.second.max_, max);
     return max;
   }

   void Reset() {
     for (auto& it : samples_)
       it.second.Reset();
     total_count_ = 0;
   }

   int64_t Diff() const {
     int64_t sum_diff = 0;
     int count = 0;
     for (const auto& it : samples_) {
       if (it.second.count_ > 0) {
         int64_t diff = it.second.sum_ - it.second.last_sum_;
         if (diff >= 0) {
           sum_diff += diff;
           ++count;
         }
       }
     }
     return (count > 0) ? sum_diff : -1;
   }

  private:
   struct Stats {
     void Add(int sample) {
       sum_ += sample;
       ++count_;
       max_ = std::max(sample, max_);
     }
     void Set(int sample) {
       sum_ = sample;
       ++count_;
     }
     void Reset() {
       if (count_ > 0)
         last_sum_ = sum_;
       sum_ = 0;
       count_ = 0;
       max_ = std::numeric_limits<int>::min();
     }

     int max_ = std::numeric_limits<int>::min();
     int64_t count_ = 0;
     int64_t sum_ = 0;
     int64_t last_sum_ = 0;
   };

   int64_t total_count_;
   std::map<uint32_t, Stats> samples_;  // Gathered samples mapped by stream id.
 };

 // StatsCounter class.
 StatsCounter::StatsCounter(Clock* clock,
                            int64_t process_intervals_ms,
                            bool include_empty_intervals,
                            StatsCounterObserver* observer)
     : include_empty_intervals_(include_empty_intervals),
       process_intervals_ms_(process_intervals_ms),
       aggregated_counter_(new AggregatedCounter()),
       samples_(new Samples()),
       clock_(clock),
       observer_(observer),
       last_process_time_ms_(-1),
       paused_(false) {
   RTC_DCHECK_GT(process_intervals_ms_, 0);
 }

 StatsCounter::~StatsCounter() {}

 AggregatedStats StatsCounter::GetStats() {
   return aggregated_counter_->ComputeStats();
 }

 AggregatedStats StatsCounter::ProcessAndGetStats() {
   if (HasSample())
     TryProcess();
   return aggregated_counter_->ComputeStats();
 }

 void StatsCounter::ProcessAndPause() {
   if (HasSample())
     TryProcess();
   paused_ = true;
 }

 bool StatsCounter::HasSample() const {
   return last_process_time_ms_ != -1;
 }

 bool StatsCounter::TimeToProcess(int* elapsed_intervals) {
   int64_t now = clock_->TimeInMilliseconds();
   if (last_process_time_ms_ == -1)
     last_process_time_ms_ = now;

   int64_t diff_ms = now - last_process_time_ms_;
   if (diff_ms < process_intervals_ms_)
     return false;

   // Advance number of complete |process_intervals_ms_| that have passed.
   int64_t num_intervals = diff_ms / process_intervals_ms_;
   last_process_time_ms_ += num_intervals * process_intervals_ms_;

   *elapsed_intervals = num_intervals;
   return true;
 }

 void StatsCounter::Set(int sample, uint32_t stream_id) {
   TryProcess();
   samples_->Set(sample, stream_id);
   paused_ = false;
 }

 void StatsCounter::Add(int sample) {
   TryProcess();
   samples_->Add(sample, kStreamId0);
   paused_ = false;
 }

 // Reports periodically computed metric.
 void StatsCounter::ReportMetricToAggregatedCounter(
     int value,
     int num_values_to_add) const {
   for (int i = 0; i < num_values_to_add; ++i) {
     aggregated_counter_->Add(value);
     if (observer_)
       observer_->OnMetricUpdated(value);
   }
 }

 void StatsCounter::TryProcess() {
   int elapsed_intervals;
   if (!TimeToProcess(&elapsed_intervals))
     return;

   // Get and report periodically computed metric.
   int metric;
   if (GetMetric(&metric))
     ReportMetricToAggregatedCounter(metric, 1);

   // Report value for elapsed intervals without samples.
   if (IncludeEmptyIntervals()) {
     // If there are no samples, all elapsed intervals are empty (otherwise one
     // interval contains sample(s), discard this interval).
     int empty_intervals =
         samples_->Empty() ? elapsed_intervals : (elapsed_intervals - 1);
     ReportMetricToAggregatedCounter(GetValueForEmptyInterval(),
                                     empty_intervals);
   }

   // Reset samples for elapsed interval.
   samples_->Reset();
 }

 bool StatsCounter::IncludeEmptyIntervals() const {
   return include_empty_intervals_ && !paused_ && !aggregated_counter_->Empty();
 }

 // StatsCounter sub-classes.
 AvgCounter::AvgCounter(Clock* clock,
                        StatsCounterObserver* observer,
                        bool include_empty_intervals)
     : StatsCounter(clock,
                    kDefaultProcessIntervalMs,
                    include_empty_intervals,
                    observer) {}

 void AvgCounter::Add(int sample) {
   StatsCounter::Add(sample);
 }

 bool AvgCounter::GetMetric(int* metric) const {
   int64_t count = samples_->Count();
   if (count == 0)
     return false;

   *metric = (samples_->Sum() + count / 2) / count;
   return true;
 }

 int AvgCounter::GetValueForEmptyInterval() const {
   return aggregated_counter_->last_sample();
 }

 MaxCounter::MaxCounter(Clock* clock,
                        StatsCounterObserver* observer,
                        int64_t process_intervals_ms)
     : StatsCounter(clock,
                    process_intervals_ms,
                    false,  // |include_empty_intervals|
                    observer) {}

 void MaxCounter::Add(int sample) {
   StatsCounter::Add(sample);
 }

 bool MaxCounter::GetMetric(int* metric) const {
   if (samples_->Empty())
     return false;

   *metric = samples_->Max();
   return true;
 }

 int MaxCounter::GetValueForEmptyInterval() const {
   RTC_NOTREACHED();
   return 0;
 }

 PercentCounter::PercentCounter(Clock* clock, StatsCounterObserver* observer)
     : StatsCounter(clock,
                    kDefaultProcessIntervalMs,
                    false,  // |include_empty_intervals|
                    observer) {}

 void PercentCounter::Add(bool sample) {
   StatsCounter::Add(sample ? 1 : 0);
 }

 bool PercentCounter::GetMetric(int* metric) const {
   int64_t count = samples_->Count();
   if (count == 0)
     return false;

   *metric = (samples_->Sum() * 100 + count / 2) / count;
   return true;
 }

 int PercentCounter::GetValueForEmptyInterval() const {
   RTC_NOTREACHED();
   return 0;
 }

 PermilleCounter::PermilleCounter(Clock* clock, StatsCounterObserver* observer)
     : StatsCounter(clock,
                    kDefaultProcessIntervalMs,
                    false,  // |include_empty_intervals|
                    observer) {}

 void PermilleCounter::Add(bool sample) {
   StatsCounter::Add(sample ? 1 : 0);
 }

 bool PermilleCounter::GetMetric(int* metric) const {
   int64_t count = samples_->Count();
   if (count == 0)
     return false;

   *metric = (samples_->Sum() * 1000 + count / 2) / count;
   return true;
 }

 int PermilleCounter::GetValueForEmptyInterval() const {
   RTC_NOTREACHED();
   return 0;
 }

 RateCounter::RateCounter(Clock* clock,
                          StatsCounterObserver* observer,
                          bool include_empty_intervals)
     : StatsCounter(clock,
                    kDefaultProcessIntervalMs,
                    include_empty_intervals,
                    observer) {}

 void RateCounter::Add(int sample) {
   StatsCounter::Add(sample);
 }

 bool RateCounter::GetMetric(int* metric) const {
   if (samples_->Empty())
     return false;

   *metric = (samples_->Sum() * 1000 + process_intervals_ms_ / 2) /
             process_intervals_ms_;
   return true;
 }

 int RateCounter::GetValueForEmptyInterval() const {
   return 0;
 }

 RateAccCounter::RateAccCounter(Clock* clock,
                                StatsCounterObserver* observer,
                                bool include_empty_intervals)
     : StatsCounter(clock,
                    kDefaultProcessIntervalMs,
                    include_empty_intervals,
                    observer) {}

 void RateAccCounter::Set(int sample, uint32_t stream_id) {
   StatsCounter::Set(sample, stream_id);
 }

 bool RateAccCounter::GetMetric(int* metric) const {
   int64_t diff = samples_->Diff();
   if (diff < 0 || (!include_empty_intervals_ && diff == 0))
     return false;

   *metric = (diff * 1000 + process_intervals_ms_ / 2) / process_intervals_ms_;
   return true;
 }

 int RateAccCounter::GetValueForEmptyInterval() const {
   return 0;
 }

 }  // namespace webrtc
	/*
	* Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
	*
	* Use of this source code is governed by a BSD-style license
	* that can be found in the LICENSE file in the root of the source
	* tree. An additional intellectual property rights grant can be found
	* in the file PATENTS. All contributing project authors may
	* be found in the AUTHORS file in the root of the source tree.
	*/

	#include "webrtc/video/stats_counter.h"

	#include <algorithm>
	#include <limits>
	#include <map>

	#include "webrtc/base/checks.h"
	#include "webrtc/system_wrappers/include/clock.h"

	namespace webrtc {

	namespace {
	// Default periodic time interval for processing samples.
	const int64_t kDefaultProcessIntervalMs = 2000;
	const uint32_t kStreamId0 = 0;
	} // namespace

	std::string AggregatedStats::ToString() const {
	return ToStringWithMultiplier(1);
	}

	std::string AggregatedStats::ToStringWithMultiplier(int multiplier) const {
	std::stringstream ss;
	ss << "periodic_samples:" << num_samples << ", {";
	ss << "min:" << (min * multiplier) << ", ";
	ss << "avg:" << (average * multiplier) << ", ";
	ss << "max:" << (max * multiplier) << "}";
	return ss.str();
	}

	// Class holding periodically computed metrics.
	class AggregatedCounter {
	public:
	AggregatedCounter() : last_sample_(0), sum_samples_(0) {}
	~AggregatedCounter() {}

	void Add(int sample) {
	last_sample_ = sample;
	sum_samples_ += sample;
	++stats_.num_samples;
	if (stats_.num_samples == 1) {
	stats_.min = sample;
	stats_.max = sample;
	}
	stats_.min = std::min(sample, stats_.min);
	stats_.max = std::max(sample, stats_.max);
	}

	AggregatedStats ComputeStats() {
	Compute();
	return stats_;
	}

	bool Empty() const { return stats_.num_samples == 0; }

	int last_sample() const { return last_sample_; }

	private:
	void Compute() {
	if (stats_.num_samples == 0)
	return;

	stats_.average =
	(sum_samples_ + stats_.num_samples / 2) / stats_.num_samples;
	}
	int last_sample_;
	int64_t sum_samples_;
	AggregatedStats stats_;
	};

	// Class holding gathered samples within a process interval.
	class Samples {
	public:
	Samples() : total_count_(0) {}
	~Samples() {}

	void Add(int sample, uint32_t stream_id) {
	samples_[stream_id].Add(sample);
	++total_count_;
	}
	void Set(int sample, uint32_t stream_id) {
	samples_[stream_id].Set(sample);
	++total_count_;
	}

	int64_t Count() const { return total_count_; }
	bool Empty() const { return total_count_ == 0; }

	int64_t Sum() const {
	int64_t sum = 0;
	for (const auto& it : samples_)
	sum += it.second.sum_;
	return sum;
	}

	int Max() const {
	int max = std::numeric_limits<int>::min();
	for (const auto& it : samples_)
	max = std::max(it.second.max_, max);
	return max;
	}

	void Reset() {
	for (auto& it : samples_)
	it.second.Reset();
	total_count_ = 0;
	}

	int64_t Diff() const {
	int64_t sum_diff = 0;
	int count = 0;
	for (const auto& it : samples_) {
	if (it.second.count_ > 0) {
	int64_t diff = it.second.sum_ - it.second.last_sum_;
	if (diff >= 0) {
	sum_diff += diff;
	++count;
	}
	}
	}
	return (count > 0) ? sum_diff : -1;
	}

	private:
	struct Stats {
	void Add(int sample) {
	sum_ += sample;
	++count_;
	max_ = std::max(sample, max_);
	}
	void Set(int sample) {
	sum_ = sample;
	++count_;
	}
	void Reset() {
	if (count_ > 0)
	last_sum_ = sum_;
	sum_ = 0;
	count_ = 0;
	max_ = std::numeric_limits<int>::min();
	}

	int max_ = std::numeric_limits<int>::min();
	int64_t count_ = 0;
	int64_t sum_ = 0;
	int64_t last_sum_ = 0;
	};

	int64_t total_count_;
	std::map<uint32_t, Stats> samples_; // Gathered samples mapped by stream id.
	};

	// StatsCounter class.
	StatsCounter::StatsCounter(Clock* clock,
	int64_t process_intervals_ms,
	bool include_empty_intervals,
	StatsCounterObserver* observer)
	: include_empty_intervals_(include_empty_intervals),
	process_intervals_ms_(process_intervals_ms),
	aggregated_counter_(new AggregatedCounter()),
	samples_(new Samples()),
	clock_(clock),
	observer_(observer),
	last_process_time_ms_(-1),
	paused_(false) {
	RTC_DCHECK_GT(process_intervals_ms_, 0);
	}

	StatsCounter::~StatsCounter() {}

	AggregatedStats StatsCounter::GetStats() {
	return aggregated_counter_->ComputeStats();
	}

	AggregatedStats StatsCounter::ProcessAndGetStats() {
	if (HasSample())
	TryProcess();
	return aggregated_counter_->ComputeStats();
	}

	void StatsCounter::ProcessAndPause() {
	if (HasSample())
	TryProcess();
	paused_ = true;
	}

	bool StatsCounter::HasSample() const {
	return last_process_time_ms_ != -1;
	}

	bool StatsCounter::TimeToProcess(int* elapsed_intervals) {
	int64_t now = clock_->TimeInMilliseconds();
	if (last_process_time_ms_ == -1)
	last_process_time_ms_ = now;

	int64_t diff_ms = now - last_process_time_ms_;
	if (diff_ms < process_intervals_ms_)
	return false;

	// Advance number of complete \|process_intervals_ms_\| that have passed.
	int64_t num_intervals = diff_ms / process_intervals_ms_;
	last_process_time_ms_ += num_intervals * process_intervals_ms_;

	*elapsed_intervals = num_intervals;
	return true;
	}

	void StatsCounter::Set(int sample, uint32_t stream_id) {
	TryProcess();
	samples_->Set(sample, stream_id);
	paused_ = false;
	}

	void StatsCounter::Add(int sample) {
	TryProcess();
	samples_->Add(sample, kStreamId0);
	paused_ = false;
	}

	// Reports periodically computed metric.
	void StatsCounter::ReportMetricToAggregatedCounter(
	int value,
	int num_values_to_add) const {
	for (int i = 0; i < num_values_to_add; ++i) {
	aggregated_counter_->Add(value);
	if (observer_)
	observer_->OnMetricUpdated(value);
	}
	}

	void StatsCounter::TryProcess() {
	int elapsed_intervals;
	if (!TimeToProcess(&elapsed_intervals))
	return;

	// Get and report periodically computed metric.
	int metric;
	if (GetMetric(&metric))
	ReportMetricToAggregatedCounter(metric, 1);

	// Report value for elapsed intervals without samples.
	if (IncludeEmptyIntervals()) {
	// If there are no samples, all elapsed intervals are empty (otherwise one
	// interval contains sample(s), discard this interval).
	int empty_intervals =
	samples_->Empty() ? elapsed_intervals : (elapsed_intervals - 1);
	ReportMetricToAggregatedCounter(GetValueForEmptyInterval(),
	empty_intervals);
	}

	// Reset samples for elapsed interval.
	samples_->Reset();
	}

	bool StatsCounter::IncludeEmptyIntervals() const {
	return include_empty_intervals_ && !paused_ && !aggregated_counter_->Empty();
	}

	// StatsCounter sub-classes.
	AvgCounter::AvgCounter(Clock* clock,
	StatsCounterObserver* observer,
	bool include_empty_intervals)
	: StatsCounter(clock,
	kDefaultProcessIntervalMs,
	include_empty_intervals,
	observer) {}

	void AvgCounter::Add(int sample) {
	StatsCounter::Add(sample);
	}

	bool AvgCounter::GetMetric(int* metric) const {
	int64_t count = samples_->Count();
	if (count == 0)
	return false;

	*metric = (samples_->Sum() + count / 2) / count;
	return true;
	}

	int AvgCounter::GetValueForEmptyInterval() const {
	return aggregated_counter_->last_sample();
	}

	MaxCounter::MaxCounter(Clock* clock,
	StatsCounterObserver* observer,
	int64_t process_intervals_ms)
	: StatsCounter(clock,
	process_intervals_ms,
	false, // \|include_empty_intervals\|
	observer) {}

	void MaxCounter::Add(int sample) {
	StatsCounter::Add(sample);
	}

	bool MaxCounter::GetMetric(int* metric) const {
	if (samples_->Empty())
	return false;

	*metric = samples_->Max();
	return true;
	}

	int MaxCounter::GetValueForEmptyInterval() const {
	RTC_NOTREACHED();
	return 0;
	}

	PercentCounter::PercentCounter(Clock* clock, StatsCounterObserver* observer)
	: StatsCounter(clock,
	kDefaultProcessIntervalMs,
	false, // \|include_empty_intervals\|
	observer) {}

	void PercentCounter::Add(bool sample) {
	StatsCounter::Add(sample ? 1 : 0);
	}

	bool PercentCounter::GetMetric(int* metric) const {
	int64_t count = samples_->Count();
	if (count == 0)
	return false;

	metric = (samples_->Sum() 100 + count / 2) / count;
	return true;
	}

	int PercentCounter::GetValueForEmptyInterval() const {
	RTC_NOTREACHED();
	return 0;
	}

	PermilleCounter::PermilleCounter(Clock* clock, StatsCounterObserver* observer)
	: StatsCounter(clock,
	kDefaultProcessIntervalMs,
	false, // \|include_empty_intervals\|
	observer) {}

	void PermilleCounter::Add(bool sample) {
	StatsCounter::Add(sample ? 1 : 0);
	}

	bool PermilleCounter::GetMetric(int* metric) const {
	int64_t count = samples_->Count();
	if (count == 0)
	return false;

	metric = (samples_->Sum() 1000 + count / 2) / count;
	return true;
	}

	int PermilleCounter::GetValueForEmptyInterval() const {
	RTC_NOTREACHED();
	return 0;
	}

	RateCounter::RateCounter(Clock* clock,
	StatsCounterObserver* observer,
	bool include_empty_intervals)
	: StatsCounter(clock,
	kDefaultProcessIntervalMs,
	include_empty_intervals,
	observer) {}

	void RateCounter::Add(int sample) {
	StatsCounter::Add(sample);
	}

	bool RateCounter::GetMetric(int* metric) const {
	if (samples_->Empty())
	return false;

	metric = (samples_->Sum() 1000 + process_intervals_ms_ / 2) /
	process_intervals_ms_;
	return true;
	}

	int RateCounter::GetValueForEmptyInterval() const {
	return 0;
	}

	RateAccCounter::RateAccCounter(Clock* clock,
	StatsCounterObserver* observer,
	bool include_empty_intervals)
	: StatsCounter(clock,
	kDefaultProcessIntervalMs,
	include_empty_intervals,
	observer) {}

	void RateAccCounter::Set(int sample, uint32_t stream_id) {
	StatsCounter::Set(sample, stream_id);
	}

	bool RateAccCounter::GetMetric(int* metric) const {
	int64_t diff = samples_->Diff();
	if (diff < 0 \|\| (!include_empty_intervals_ && diff == 0))
	return false;

	metric = (diff 1000 + process_intervals_ms_ / 2) / process_intervals_ms_;
	return true;
	}

	int RateAccCounter::GetValueForEmptyInterval() const {
	return 0;
	}

	} // namespace webrtc