Almost full implementation of BBR's core.

webrtc/modules/remote_bitrate_estimator/test/estimators/max_bandwidth_filter.cc

 /*
  *  Copyright (c) 2017 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/modules/remote_bitrate_estimator/test/estimators/max_bandwidth_filter.h"
 
 namespace webrtc {
 namespace testing {
 namespace bwe {
+
+const size_t MaxBandwidthFilter::kBandwidthWindowFilterSize;
+
 MaxBandwidthFilter::MaxBandwidthFilter()
     : bandwidth_last_round_bytes_per_ms_(0),
       max_bandwidth_estimate_bps_(0),
       rounds_without_growth_(0) {}
 
 MaxBandwidthFilter::~MaxBandwidthFilter() {}
 
 // For detailed explanation about implementing bandwidth filter this way visit
 // "Bbr design" doc. |sample_bps| was measured during |round|.
-void MaxBandwidthFilter::AddBandwidthSample(int64_t sample_bps,
-                                            int64_t round,
-                                            size_t filter_size_round) {
+void MaxBandwidthFilter::AddBandwidthSample(int64_t sample_bps, int64_t round) {
   if (bandwidth_samples_[0].first == 0 ||
       sample_bps >= bandwidth_samples_[0].first ||
-      round - bandwidth_samples_[2].second >= filter_size_round)
+      round - bandwidth_samples_[2].second >=
+          MaxBandwidthFilter::kBandwidthWindowFilterSize)
     bandwidth_samples_[0] = bandwidth_samples_[1] =
         bandwidth_samples_[2] = {sample_bps, round};
   if (sample_bps >= bandwidth_samples_[1].first) {
     bandwidth_samples_[1] = {sample_bps, round};
     bandwidth_samples_[2] = bandwidth_samples_[1];
   } else {
     if (sample_bps >= bandwidth_samples_[2].first)
       bandwidth_samples_[2] = {sample_bps, round};
   }
-  if (round - bandwidth_samples_[0].second >= filter_size_round) {
+  if (round - bandwidth_samples_[0].second >=
+      MaxBandwidthFilter::kBandwidthWindowFilterSize) {
     bandwidth_samples_[0] = bandwidth_samples_[1];
     bandwidth_samples_[1] = bandwidth_samples_[2];
     bandwidth_samples_[2] = {sample_bps, round};
-    if (round - bandwidth_samples_[0].second >= filter_size_round) {
+    if (round - bandwidth_samples_[0].second >=
+        MaxBandwidthFilter::kBandwidthWindowFilterSize) {
       bandwidth_samples_[0] = bandwidth_samples_[1];
       bandwidth_samples_[1] = bandwidth_samples_[2];
     }
     max_bandwidth_estimate_bps_ = bandwidth_samples_[0].first;
     return;
   }
   if (bandwidth_samples_[1].first == bandwidth_samples_[0].first &&
-      round - bandwidth_samples_[1].second > filter_size_round / 4) {
+      round - bandwidth_samples_[1].second >
+          MaxBandwidthFilter::kBandwidthWindowFilterSize / 4) {
     bandwidth_samples_[2] = bandwidth_samples_[1] = {sample_bps, round};
     max_bandwidth_estimate_bps_ = bandwidth_samples_[0].first;
     return;
   }
   if (bandwidth_samples_[2].first == bandwidth_samples_[1].first &&
-      round - bandwidth_samples_[2].second > filter_size_round / 2)
+      round - bandwidth_samples_[2].second >
+          MaxBandwidthFilter::kBandwidthWindowFilterSize / 2)
     bandwidth_samples_[2] = {sample_bps, round};
   max_bandwidth_estimate_bps_ = bandwidth_samples_[0].first;
 }
 
 bool MaxBandwidthFilter::FullBandwidthReached(float growth_target,
                                               int max_rounds_without_growth) {
   // Minimal bandwidth necessary to assume that better bandwidth can still be
   // found and full bandwidth is not reached.
   int64_t minimal_bandwidth =
       bandwidth_last_round_bytes_per_ms_ * growth_target;
   if (max_bandwidth_estimate_bps_ >= minimal_bandwidth) {
     bandwidth_last_round_bytes_per_ms_ = max_bandwidth_estimate_bps_;
     rounds_without_growth_ = 0;
     return false;
   }
   rounds_without_growth_++;
   return rounds_without_growth_ >= max_rounds_without_growth;
 }
 }  // namespace bwe
 }  // namespace testing
 }  // namespace webrtc