1 /* 2 * Copyright (c) 2019 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 MODULES_AUDIO_CODING_NETEQ_HISTOGRAM_H_ 12 #define MODULES_AUDIO_CODING_NETEQ_HISTOGRAM_H_ 13 14 #include <string.h> // Provide access to size_t. 15 16 #include <vector> 17 18 #include "absl/types/optional.h" 19 20 namespace webrtc { 21 22 class Histogram { 23 public: 24 // Creates histogram with capacity |num_buckets| and |forget_factor| in Q15. 25 Histogram(size_t num_buckets, 26 int forget_factor, 27 absl::optional<double> start_forget_weight = absl::nullopt); 28 29 virtual ~Histogram(); 30 31 // Resets the histogram to the default start distribution. 32 virtual void Reset(); 33 34 // Add entry in bucket |index|. 35 virtual void Add(int index); 36 37 // Calculates the quantile at |probability| (in Q30) of the histogram 38 // distribution. 39 virtual int Quantile(int probability); 40 41 // Returns the number of buckets in the histogram. 42 virtual int NumBuckets() const; 43 44 // Returns the probability for each bucket in Q30. buckets()45 std::vector<int> buckets() const { return buckets_; } 46 47 // Accessors only intended for testing purposes. base_forget_factor_for_testing()48 int base_forget_factor_for_testing() const { return base_forget_factor_; } forget_factor_for_testing()49 int forget_factor_for_testing() const { return forget_factor_; } start_forget_weight_for_testing()50 absl::optional<double> start_forget_weight_for_testing() const { 51 return start_forget_weight_; 52 } 53 54 private: 55 std::vector<int> buckets_; 56 int forget_factor_; // Q15 57 const int base_forget_factor_; 58 int add_count_; 59 const absl::optional<double> start_forget_weight_; 60 }; 61 62 } // namespace webrtc 63 64 #endif // MODULES_AUDIO_CODING_NETEQ_HISTOGRAM_H_ 65