Introduce FecControllerRplrBased

webrtc/modules/audio_coding/audio_network_adaptor/fec_controller_plr_based.cc

 /*
  *  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/modules/audio_coding/audio_network_adaptor/fec_controller.h"
+#include "webrtc/modules/audio_coding/audio_network_adaptor/fec_controller_plr_based.h"
 
 #include <limits>
 #include <utility>
 
 #include "webrtc/base/checks.h"
 
 namespace webrtc {
 
-FecController::Config::Threshold::Threshold(int low_bandwidth_bps,
-                                            float low_bandwidth_packet_loss,
-                                            int high_bandwidth_bps,
-                                            float high_bandwidth_packet_loss)
+FecControllerPlrBased::Config::Threshold::Threshold(
+    int low_bandwidth_bps,
+    float low_bandwidth_packet_loss,
+    int high_bandwidth_bps,
+    float high_bandwidth_packet_loss)
     : low_bandwidth_bps(low_bandwidth_bps),
       low_bandwidth_packet_loss(low_bandwidth_packet_loss),
       high_bandwidth_bps(high_bandwidth_bps),
       high_bandwidth_packet_loss(high_bandwidth_packet_loss) {}
 
-FecController::Config::Config(bool initial_fec_enabled,
-                              const Threshold& fec_enabling_threshold,
-                              const Threshold& fec_disabling_threshold,
-                              int time_constant_ms,
-                              const Clock* clock)
+FecControllerPlrBased::Config::Config(bool initial_fec_enabled,
+                                      const Threshold& fec_enabling_threshold,
+                                      const Threshold& fec_disabling_threshold,
+                                      int time_constant_ms,
+                                      const Clock* clock)
     : initial_fec_enabled(initial_fec_enabled),
       fec_enabling_threshold(fec_enabling_threshold),
       fec_disabling_threshold(fec_disabling_threshold),
       time_constant_ms(time_constant_ms),
       clock(clock) {}
 
-FecController::FecController(const Config& config,
-                             std::unique_ptr<SmoothingFilter> smoothing_filter)
+FecControllerPlrBased::FecControllerPlrBased(
+    const Config& config,
+    std::unique_ptr<SmoothingFilter> smoothing_filter)
     : config_(config),
       fec_enabled_(config.initial_fec_enabled),
       packet_loss_smoother_(std::move(smoothing_filter)),
       fec_enabling_threshold_info_(config_.fec_enabling_threshold),
       fec_disabling_threshold_info_(config_.fec_disabling_threshold) {
   RTC_DCHECK_LE(fec_enabling_threshold_info_.slope, 0);
   RTC_DCHECK_LE(fec_enabling_threshold_info_.slope, 0);
   RTC_DCHECK_LE(
       GetPacketLossThreshold(config_.fec_enabling_threshold.low_bandwidth_bps,
                              config_.fec_disabling_threshold,
                              fec_disabling_threshold_info_),
       config_.fec_enabling_threshold.low_bandwidth_packet_loss);
   RTC_DCHECK_LE(
       GetPacketLossThreshold(config_.fec_enabling_threshold.high_bandwidth_bps,
                              config_.fec_disabling_threshold,
                              fec_disabling_threshold_info_),
       config_.fec_enabling_threshold.high_bandwidth_packet_loss);
 }
 
-FecController::FecController(const Config& config)
-    : FecController(
+FecControllerPlrBased::FecControllerPlrBased(const Config& config)
+    : FecControllerPlrBased(
           config,
           std::unique_ptr<SmoothingFilter>(
               new SmoothingFilterImpl(config.time_constant_ms, config.clock))) {
 }
 
-FecController::~FecController() = default;
+FecControllerPlrBased::~FecControllerPlrBased() = default;
 
-void FecController::UpdateNetworkMetrics(
+void FecControllerPlrBased::UpdateNetworkMetrics(
     const NetworkMetrics& network_metrics) {
   if (network_metrics.uplink_bandwidth_bps)
     uplink_bandwidth_bps_ = network_metrics.uplink_bandwidth_bps;
   if (network_metrics.uplink_packet_loss_fraction) {
     packet_loss_smoother_->AddSample(
         *network_metrics.uplink_packet_loss_fraction);
   }
 }
 
-void FecController::MakeDecision(
+void FecControllerPlrBased::MakeDecision(
     AudioNetworkAdaptor::EncoderRuntimeConfig* config) {
   RTC_DCHECK(!config->enable_fec);
   RTC_DCHECK(!config->uplink_packet_loss_fraction);
 
   const auto& packet_loss = packet_loss_smoother_->GetAverage();
 
   fec_enabled_ = fec_enabled_ ? !FecDisablingDecision(packet_loss)
                               : FecEnablingDecision(packet_loss);
 
   config->enable_fec = rtc::Optional<bool>(fec_enabled_);
 
   config->uplink_packet_loss_fraction =
       rtc::Optional<float>(packet_loss ? *packet_loss : 0.0);
 }
 
-FecController::ThresholdInfo::ThresholdInfo(
+FecControllerPlrBased::ThresholdInfo::ThresholdInfo(
     const Config::Threshold& threshold) {
   int bandwidth_diff_bps =
       threshold.high_bandwidth_bps - threshold.low_bandwidth_bps;
   float packet_loss_diff = threshold.high_bandwidth_packet_loss -
                            threshold.low_bandwidth_packet_loss;
   slope = bandwidth_diff_bps == 0 ? 0.0 : packet_loss_diff / bandwidth_diff_bps;
   offset =
       threshold.low_bandwidth_packet_loss - slope * threshold.low_bandwidth_bps;
 }
 
-float FecController::GetPacketLossThreshold(
+float FecControllerPlrBased::GetPacketLossThreshold(
     int bandwidth_bps,
     const Config::Threshold& threshold,
     const ThresholdInfo& threshold_info) const {
-  if (bandwidth_bps < threshold.low_bandwidth_bps)
+  if (bandwidth_bps < threshold.low_bandwidth_bps) {
     return std::numeric_limits<float>::max();
-  if (bandwidth_bps >= threshold.high_bandwidth_bps)
+  } else if (bandwidth_bps >= threshold.high_bandwidth_bps) {
     return threshold.high_bandwidth_packet_loss;
-  return threshold_info.offset + threshold_info.slope * bandwidth_bps;
+  } else {
+    float rc = threshold_info.offset + threshold_info.slope * bandwidth_bps;
+    RTC_DCHECK_LE(rc, threshold.low_bandwidth_packet_loss);
+    RTC_DCHECK_GE(rc, threshold.high_bandwidth_packet_loss);
+    return rc;
+  }
 }
 
-bool FecController::FecEnablingDecision(
+bool FecControllerPlrBased::FecEnablingDecision(
     const rtc::Optional<float>& packet_loss) const {
   if (!uplink_bandwidth_bps_)
     return false;
   if (!packet_loss)
     return false;
   return *packet_loss >= GetPacketLossThreshold(*uplink_bandwidth_bps_,
                                                 config_.fec_enabling_threshold,
                                                 fec_enabling_threshold_info_);
 }
 
-bool FecController::FecDisablingDecision(
+bool FecControllerPlrBased::FecDisablingDecision(
     const rtc::Optional<float>& packet_loss) const {
   if (!uplink_bandwidth_bps_)
     return false;
   if (!packet_loss)
     return false;
   return *packet_loss <= GetPacketLossThreshold(*uplink_bandwidth_bps_,
                                                 config_.fec_disabling_threshold,
                                                 fec_disabling_threshold_info_);
 }
 
 }  // namespace webrtc