blob: e3d7a660bf0879193155d009e8c822dc79adb7d2 [file] [log] [blame]
/*
* Copyright (c) 2018 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 "modules/audio_processing/aec3/suppression_gain_limiter.h"
#include <math.h>
#include <algorithm>
#include "modules/audio_processing/aec3/aec3_common.h"
namespace webrtc {
namespace {
// Computes the gain rampup factor to use.
float ComputeGainRampupIncrease(
const EchoCanceller3Config::EchoRemovalControl::GainRampup& rampup_config) {
return powf(1.f / rampup_config.first_non_zero_gain,
1.f / rampup_config.non_zero_gain_blocks);
}
} // namespace
SuppressionGainUpperLimiter::SuppressionGainUpperLimiter(
const EchoCanceller3Config& config)
: rampup_config_(config.echo_removal_control.gain_rampup),
gain_rampup_increase_(ComputeGainRampupIncrease(rampup_config_)) {
Reset();
}
void SuppressionGainUpperLimiter::Reset() {
recent_reset_ = true;
}
void SuppressionGainUpperLimiter::Update(bool render_activity,
bool transparent_mode) {
if (transparent_mode) {
active_render_seen_ = true;
call_startup_phase_ = false;
recent_reset_ = false;
suppressor_gain_limit_ = 1.f;
return;
}
if (recent_reset_ && !call_startup_phase_) {
// Only enforce 250 ms full suppression after in-call resets,
constexpr int kMuteFramesAfterReset = kNumBlocksPerSecond / 4;
realignment_counter_ = kMuteFramesAfterReset;
} else if (!active_render_seen_ && render_activity) {
// Enforce a tailormade suppression limiting during call startup.
active_render_seen_ = true;
realignment_counter_ = rampup_config_.full_gain_blocks;
} else if (realignment_counter_ > 0) {
if (--realignment_counter_ == 0) {
call_startup_phase_ = false;
}
}
recent_reset_ = false;
// Do not enforce any gain limit on the suppressor.
if (!IsActive()) {
suppressor_gain_limit_ = 1.f;
return;
}
// Enforce full suppression.
if (realignment_counter_ > rampup_config_.non_zero_gain_blocks ||
(!call_startup_phase_ && realignment_counter_ > 0)) {
suppressor_gain_limit_ = rampup_config_.initial_gain;
return;
}
// Start increasing the gain limit.
if (realignment_counter_ == rampup_config_.non_zero_gain_blocks) {
suppressor_gain_limit_ = rampup_config_.first_non_zero_gain;
return;
}
// Increase the gain limit until it reaches 1.f.
RTC_DCHECK_LT(0.f, suppressor_gain_limit_);
suppressor_gain_limit_ =
std::min(1.f, suppressor_gain_limit_ * gain_rampup_increase_);
RTC_DCHECK_GE(1.f, suppressor_gain_limit_);
}
} // namespace webrtc