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Replacing bandwidth adaptation trial with stable target in Opus encoder.

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This also means that the NetworkEstimate::bandwidth can be deprecated
as it's currently just a copy of the target_rate.

Bug: webrtc:10981
Change-Id: I1bc57b98480bd77ce052736b19d630c775428546
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/153669
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Reviewed-by: Oskar Sundbom <ossu@webrtc.org>
Reviewed-by: Per Kjellander <perkj@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29288}
This commit is contained in:
Sebastian Jansson
2019-09-24 17:55:50 +02:00
committed by Commit Bot
parent c30bc169ea
commit f34116e356
16 changed files with 39 additions and 67 deletions
Download Patch File Download Diff File Expand all files Collapse all files

68
modules/audio_coding/codecs/opus/audio_encoder_opus.cc
View File

@ -425,8 +425,8 @@ AudioEncoderOpusImpl::AudioEncoderOpusImpl(
: payload_type_(payload_type),
send_side_bwe_with_overhead_(
webrtc::field_trial::IsEnabled("WebRTC-SendSideBwe-WithOverhead")),
use_link_capacity_for_adaptation_(webrtc::field_trial::IsEnabled(
"WebRTC-Audio-LinkCapacityAdaptation")),
use_stable_target_for_adaptation_(webrtc::field_trial::IsEnabled(
"WebRTC-Audio-StableTargetAdaptation")),
adjust_bandwidth_(
webrtc::field_trial::IsEnabled("WebRTC-AdjustOpusBandwidth")),
bitrate_changed_(true),
@ -563,26 +563,28 @@ void AudioEncoderOpusImpl::OnReceivedUplinkRecoverablePacketLossFraction(
void AudioEncoderOpusImpl::OnReceivedUplinkBandwidth(
int target_audio_bitrate_bps,
absl::optional<int64_t> bwe_period_ms,
absl::optional<int64_t> link_capacity_allocation_bps) {
absl::optional<int64_t> stable_target_bitrate_bps) {
if (audio_network_adaptor_) {
audio_network_adaptor_->SetTargetAudioBitrate(target_audio_bitrate_bps);
// We give smoothed bitrate allocation to audio network adaptor as
// the uplink bandwidth.
// The BWE spikes should not affect the bitrate smoother more than 25%.
// To simplify the calculations we use a step response as input signal.
// The step response of an exponential filter is
// u(t) = 1 - e^(-t / time_constant).
// In order to limit the affect of a BWE spike within 25% of its value
// before
// the next BWE update, we would choose a time constant that fulfills
// 1 - e^(-bwe_period_ms / time_constant) < 0.25
// Then 4 * bwe_period_ms is a good choice.
if (bwe_period_ms)
bitrate_smoother_->SetTimeConstantMs(*bwe_period_ms * 4);
bitrate_smoother_->AddSample(target_audio_bitrate_bps);
if (link_capacity_allocation_bps)
link_capacity_allocation_bps_ = link_capacity_allocation_bps;
if (use_stable_target_for_adaptation_) {
if (stable_target_bitrate_bps)
audio_network_adaptor_->SetUplinkBandwidth(*stable_target_bitrate_bps);
} else {
// We give smoothed bitrate allocation to audio network adaptor as
// the uplink bandwidth.
// The BWE spikes should not affect the bitrate smoother more than 25%.
// To simplify the calculations we use a step response as input signal.
// The step response of an exponential filter is
// u(t) = 1 - e^(-t / time_constant).
// In order to limit the affect of a BWE spike within 25% of its value
// before
// the next BWE update, we would choose a time constant that fulfills
// 1 - e^(-bwe_period_ms / time_constant) < 0.25
// Then 4 * bwe_period_ms is a good choice.
if (bwe_period_ms)
bitrate_smoother_->SetTimeConstantMs(*bwe_period_ms * 4);
bitrate_smoother_->AddSample(target_audio_bitrate_bps);
}
ApplyAudioNetworkAdaptor();
} else if (send_side_bwe_with_overhead_) {
@ -612,7 +614,7 @@ void AudioEncoderOpusImpl::OnReceivedUplinkBandwidth(
void AudioEncoderOpusImpl::OnReceivedUplinkAllocation(
BitrateAllocationUpdate update) {
OnReceivedUplinkBandwidth(update.target_bitrate.bps(), update.bwe_period.ms(),
update.link_capacity.bps());
update.stable_target_bitrate.bps());
}
void AudioEncoderOpusImpl::OnReceivedRtt(int rtt_ms) {
@ -857,21 +859,15 @@ AudioEncoderOpusImpl::DefaultAudioNetworkAdaptorCreator(
}
void AudioEncoderOpusImpl::MaybeUpdateUplinkBandwidth() {
if (audio_network_adaptor_) {
if (use_link_capacity_for_adaptation_ && link_capacity_allocation_bps_) {
audio_network_adaptor_->SetUplinkBandwidth(
*link_capacity_allocation_bps_);
} else {
int64_t now_ms = rtc::TimeMillis();
if (!bitrate_smoother_last_update_time_ ||
now_ms - *bitrate_smoother_last_update_time_ >=
config_.uplink_bandwidth_update_interval_ms) {
absl::optional<float> smoothed_bitrate =
bitrate_smoother_->GetAverage();
if (smoothed_bitrate)
audio_network_adaptor_->SetUplinkBandwidth(*smoothed_bitrate);
bitrate_smoother_last_update_time_ = now_ms;
}
if (audio_network_adaptor_ && !use_stable_target_for_adaptation_) {
int64_t now_ms = rtc::TimeMillis();
if (!bitrate_smoother_last_update_time_ ||
now_ms - *bitrate_smoother_last_update_time_ >=
config_.uplink_bandwidth_update_interval_ms) {
absl::optional<float> smoothed_bitrate = bitrate_smoother_->GetAverage();
if (smoothed_bitrate)
audio_network_adaptor_->SetUplinkBandwidth(*smoothed_bitrate);
bitrate_smoother_last_update_time_ = now_ms;
}
}
}

3
modules/audio_coding/codecs/opus/audio_encoder_opus.h
View File

@ -174,7 +174,7 @@ class AudioEncoderOpusImpl final : public AudioEncoder {
AudioEncoderOpusConfig config_;
const int payload_type_;
const bool send_side_bwe_with_overhead_;
const bool use_link_capacity_for_adaptation_;
const bool use_stable_target_for_adaptation_;
const bool adjust_bandwidth_;
bool bitrate_changed_;
float packet_loss_rate_;
@ -192,7 +192,6 @@ class AudioEncoderOpusImpl final : public AudioEncoder {
absl::optional<size_t> overhead_bytes_per_packet_;
const std::unique_ptr<SmoothingFilter> bitrate_smoother_;
absl::optional<int64_t> bitrate_smoother_last_update_time_;
absl::optional<int64_t> link_capacity_allocation_bps_;
int consecutive_dtx_frames_;
friend struct AudioEncoderOpus;