| /* |
| * Copyright (c) 2019 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 "rtc_base/experiments/rate_control_settings.h" |
| |
| #include <inttypes.h> |
| #include <stdio.h> |
| |
| #include <string> |
| |
| #include "api/transport/field_trial_based_config.h" |
| #include "rtc_base/logging.h" |
| #include "rtc_base/numerics/safe_conversions.h" |
| |
| namespace webrtc { |
| |
| namespace { |
| |
| const char* kCongestionWindowFieldTrialName = "WebRTC-CwndExperiment"; |
| const int kDefaultAcceptedQueueMs = 250; |
| |
| const char* kCongestionWindowPushbackFieldTrialName = |
| "WebRTC-CongestionWindowPushback"; |
| const int kDefaultMinPushbackTargetBitrateBps = 30000; |
| |
| absl::optional<int> MaybeReadCwndExperimentParameter( |
| const WebRtcKeyValueConfig* const key_value_config) { |
| int64_t accepted_queue_ms; |
| std::string experiment_string = |
| key_value_config->Lookup(kCongestionWindowFieldTrialName); |
| int parsed_values = |
| sscanf(experiment_string.c_str(), "Enabled-%" PRId64, &accepted_queue_ms); |
| if (parsed_values == 1) { |
| RTC_CHECK_GE(accepted_queue_ms, 0) |
| << "Accepted must be greater than or equal to 0."; |
| return rtc::checked_cast<int>(accepted_queue_ms); |
| } else if (experiment_string.find("Enabled") == 0) { |
| return kDefaultAcceptedQueueMs; |
| } |
| return absl::nullopt; |
| } |
| |
| absl::optional<int> MaybeReadCongestionWindowPushbackExperimentParameter( |
| const WebRtcKeyValueConfig* const key_value_config) { |
| uint32_t min_pushback_target_bitrate_bps; |
| std::string experiment_string = |
| key_value_config->Lookup(kCongestionWindowPushbackFieldTrialName); |
| int parsed_values = sscanf(experiment_string.c_str(), "Enabled-%" PRIu32, |
| &min_pushback_target_bitrate_bps); |
| if (parsed_values == 1) { |
| RTC_CHECK_GE(min_pushback_target_bitrate_bps, 0) |
| << "Min pushback target bitrate must be greater than or equal to 0."; |
| return rtc::checked_cast<int>(min_pushback_target_bitrate_bps); |
| } else if (experiment_string.find("Enabled") == 0) { |
| return kDefaultMinPushbackTargetBitrateBps; |
| } |
| return absl::nullopt; |
| } |
| |
| } // namespace |
| |
| RateControlSettings::RateControlSettings( |
| const WebRtcKeyValueConfig* const key_value_config) |
| : congestion_window_("cwnd", |
| MaybeReadCwndExperimentParameter(key_value_config)), |
| congestion_window_pushback_( |
| "cwnd_pushback", |
| MaybeReadCongestionWindowPushbackExperimentParameter( |
| key_value_config)) { |
| ParseFieldTrial({&congestion_window_, &congestion_window_pushback_}, |
| key_value_config->Lookup("WebRTC-VideoRateControl")); |
| } |
| |
| RateControlSettings::~RateControlSettings() = default; |
| RateControlSettings::RateControlSettings(RateControlSettings&&) = default; |
| |
| RateControlSettings RateControlSettings::ParseFromFieldTrials() { |
| FieldTrialBasedConfig field_trial_config; |
| return RateControlSettings(&field_trial_config); |
| } |
| |
| RateControlSettings RateControlSettings::ParseFromKeyValueConfig( |
| const WebRtcKeyValueConfig* const key_value_config) { |
| FieldTrialBasedConfig field_trial_config; |
| return RateControlSettings(key_value_config ? key_value_config |
| : &field_trial_config); |
| } |
| |
| bool RateControlSettings::UseCongestionWindow() const { |
| return congestion_window_; |
| } |
| |
| int64_t RateControlSettings::GetCongestionWindowAdditionalTimeMs() const { |
| return congestion_window_.GetOptional().value_or(kDefaultAcceptedQueueMs); |
| } |
| |
| bool RateControlSettings::UseCongestionWindowPushback() const { |
| return congestion_window_ && congestion_window_pushback_; |
| } |
| |
| uint32_t RateControlSettings::CongestionWindowMinPushbackTargetBitrateBps() |
| const { |
| return congestion_window_pushback_.GetOptional().value_or( |
| kDefaultMinPushbackTargetBitrateBps); |
| } |
| |
| } // namespace webrtc |