1 /* 2 * Copyright (c) 2015 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef WEBRTC_MODULES_VIDEO_CODING_UTILITY_MOVING_AVERAGE_H_ 12 #define WEBRTC_MODULES_VIDEO_CODING_UTILITY_MOVING_AVERAGE_H_ 13 14 #include <list> 15 16 #include "webrtc/typedefs.h" 17 18 namespace webrtc { 19 template <class T> 20 class MovingAverage { 21 public: 22 MovingAverage(); 23 void AddSample(T sample); 24 bool GetAverage(size_t num_samples, T* average); 25 void Reset(); 26 int size(); 27 28 private: 29 T sum_; 30 std::list<T> samples_; 31 }; 32 33 template <class T> MovingAverage()34MovingAverage<T>::MovingAverage() 35 : sum_(static_cast<T>(0)) {} 36 37 template <class T> AddSample(T sample)38void MovingAverage<T>::AddSample(T sample) { 39 samples_.push_back(sample); 40 sum_ += sample; 41 } 42 43 template <class T> GetAverage(size_t num_samples,T * avg)44bool MovingAverage<T>::GetAverage(size_t num_samples, T* avg) { 45 if (num_samples > samples_.size()) 46 return false; 47 48 // Remove old samples. 49 while (num_samples < samples_.size()) { 50 sum_ -= samples_.front(); 51 samples_.pop_front(); 52 } 53 54 *avg = sum_ / static_cast<T>(num_samples); 55 return true; 56 } 57 58 template <class T> Reset()59void MovingAverage<T>::Reset() { 60 sum_ = static_cast<T>(0); 61 samples_.clear(); 62 } 63 64 template <class T> size()65int MovingAverage<T>::size() { 66 return samples_.size(); 67 } 68 69 } // namespace webrtc 70 71 #endif // WEBRTC_MODULES_VIDEO_CODING_UTILITY_MOVING_AVERAGE_H_ 72