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Reverted the new handling of saturated echoes in AEC3

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This CL reverts the changes introduced that handles echoes in AEC3.
The revert is done to match the behavior which is in M63.

Bug: webrtc:8615,chromium:792346
Change-Id: I128ccb17dc359c7889a701a2faaaf06be40f86dd
Reviewed-on: https://webrtc-review.googlesource.com/30140
Commit-Queue: Per Åhgren <peah@webrtc.org>
Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21117}
This commit is contained in:
Per Åhgren
2017-12-06 11:32:38 +01:00
committed by Commit Bot
parent d1d8dfb5c3
commit 63b494dff7
9 changed files with 106 additions and 179 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
modules/audio_processing/aec3/aec3_common.h
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@ -39,7 +39,7 @@ constexpr size_t kFftLengthBy2Minus1 = kFftLengthBy2 - 1;
constexpr size_t kFftLength = 2 * kFftLengthBy2;
constexpr int kAdaptiveFilterLength = 12;
constexpr int kUnknownDelayRenderWindowSize = 30;
constexpr int kUnknownDelayRenderWindowSize = 12;
constexpr int kAdaptiveFilterTimeDomainLength =
kAdaptiveFilterLength * kFftLengthBy2;
constexpr int kRenderTransferQueueSizeFrames = 100;

133
modules/audio_processing/aec3/aec_state.cc
View File

@ -65,11 +65,12 @@ AecState::~AecState() = default;
void AecState::HandleEchoPathChange(
const EchoPathVariability& echo_path_variability) {
const auto full_reset = [&]() {
blocks_since_last_saturation_ = kUnknownDelayRenderWindowSize + 1;
blocks_since_last_saturation_ = 0;
usable_linear_estimate_ = false;
echo_leakage_detected_ = false;
capture_signal_saturation_ = false;
echo_saturation_ = false;
previous_max_sample_ = 0.f;
max_render_.fill(0.f);
force_zero_gain_counter_ = 0;
blocks_with_filter_adaptation_ = 0;
@ -146,77 +147,50 @@ void AecState::Update(const std::vector<std::array<float, kFftLengthBy2Plus1>>&
// Update the echo audibility evaluator.
echo_audibility_.Update(x, s, converged_filter);
// Detect and flag echo saturation.
// TODO(peah): Add the delay in this computation to ensure that the render and
// capture signals are properly aligned.
RTC_DCHECK_LT(0, x.size());
const float max_sample = fabs(*std::max_element(
x.begin(), x.end(), [](float a, float b) { return a * a < b * b; }));
if (config_.ep_strength.echo_can_saturate) {
// Detect and flag echo saturation.
RTC_DCHECK_LT(0, x.size());
// Store the render values in a circular buffer.
max_render_index_ = (max_render_index_ + 1) % max_render_.size();
auto x_max_result = std::minmax_element(x.begin(), x.end());
max_render_[max_render_index_] =
std::max(fabs(*x_max_result.first), fabs(*x_max_result.second));
const bool saturated_echo =
(previous_max_sample_ > 200.f) && SaturatedCapture();
bool saturated_echo = false;
// Check for whether a saturated frame potentially could consist of
// saturated echo.
if (SaturatedCapture()) {
if (converged_filter) {
RTC_DCHECK(filter_delay_);
const size_t index =
(max_render_index_ + max_render_.size() - *filter_delay_) %
max_render_.size();
saturated_echo = max_render_[index] > 200.f;
} else {
saturated_echo =
*std::max_element(max_render_.begin(), max_render_.end()) > 200.f;
}
}
// Counts the blocks since saturation.
constexpr size_t kSaturationLeakageBlocks = 20;
// Set flag for potential presence of saturated echo
blocks_since_last_saturation_ =
saturated_echo ? 0 : blocks_since_last_saturation_ + 1;
if (converged_filter) {
echo_saturation_ =
blocks_since_last_saturation_ < kAdaptiveFilterLength + 1;
} else {
echo_saturation_ =
blocks_since_last_saturation_ < kUnknownDelayRenderWindowSize + 1;
}
// Set flag for whether the echo path is generally strong enough to saturate
// the echo.
if (converged_filter) {
// Base detection on predicted echo sample.
auto s_max_result = std::minmax_element(s.begin(), s.end());
const float s_max_abs =
std::max(fabs(*s_max_result.first), fabs(*s_max_result.second));
const bool saturated_echo_sample =
s_max_abs >= 10000.f && SaturatedCapture();
saturating_echo_path_counter_ = saturated_echo_sample
? 10 * kNumBlocksPerSecond
: saturating_echo_path_counter_ - 1;
} else {
// Base detection on detected potentially echo.
saturating_echo_path_counter_ = saturated_echo
? 10 * kNumBlocksPerSecond
: saturating_echo_path_counter_ - 1;
}
saturating_echo_path_counter_ = std::max(0, saturating_echo_path_counter_);
saturating_echo_path_ = saturating_echo_path_counter_ > 0;
echo_saturation_ = blocks_since_last_saturation_ < kSaturationLeakageBlocks;
} else {
echo_saturation_ = false;
saturating_echo_path_ = false;
saturating_echo_path_counter_ = 0;
}
previous_max_sample_ = max_sample;
// Compute render energies.
// TODO(peah): Move?
sufficient_filter_updates_ =
blocks_with_filter_adaptation_ >= kEchoPathChangeConvergenceBlocks;
initial_state_ = capture_block_counter_ < 3 * kNumBlocksPerSecond;
// Flag whether the linear filter estimate is usable.
usable_linear_estimate_ =
(!echo_saturation_) && (converged_filter || SufficientFilterUpdates()) &&
capture_block_counter_ >= 2 * kNumBlocksPerSecond && external_delay_;
linear_echo_estimate_ = UsableLinearEstimate() && !TransparentMode();
// After an amount of active render samples for which an echo should have been
// detected in the capture signal if the ERL was not infinite, flag that a
// transparent mode should be entered.
const float x_energy = std::inner_product(x.begin(), x.end(), x.begin(), 0.f);
const bool active_render_block =
x_energy > (config_.render_levels.active_render_limit *
config_.render_levels.active_render_limit) *
kFftLengthBy2;
const bool strong_render_block = x_energy > 1000 * 1000 * kFftLengthBy2;
if (active_render_block) {
render_received_ = true;
@ -226,54 +200,9 @@ void AecState::Update(const std::vector<std::array<float, kFftLengthBy2Plus1>>&
blocks_with_filter_adaptation_ +=
(active_render_block && (!SaturatedCapture()) ? 1 : 0);
blocks_with_strong_render_ +=
(strong_render_block && (!SaturatedCapture()) ? 1 : 0);
// After an amount of active render samples for which an echo should have been
// detected in the capture signal if the ERL was not infinite, flag that a
// transparent mode should be entered.
if (SaturatingEchoPath()) {
transparent_mode_ = !converged_filter &&
(!render_received_ || blocks_with_strong_render_ >=
15 * kNumBlocksPerSecond);
} else {
transparent_mode_ = !converged_filter &&
(!render_received_ ||
blocks_with_strong_render_ >= 5 * kNumBlocksPerSecond);
}
// Update flag for whether the adaptation is in the initial state.
if (SaturatingEchoPath()) {
initial_state_ = capture_block_counter_ < 6 * kNumBlocksPerSecond;
} else {
initial_state_ = capture_block_counter_ < 3 * kNumBlocksPerSecond;
}
// Detect whether the linear filter is usable.
if (SaturatingEchoPath()) {
usable_linear_estimate_ =
(!echo_saturation_) &&
(converged_filter && SufficientFilterUpdates()) &&
capture_block_counter_ >= 5 * kNumBlocksPerSecond && external_delay_;
} else {
usable_linear_estimate_ =
(!echo_saturation_) &&
(converged_filter || SufficientFilterUpdates()) &&
capture_block_counter_ >= 2 * kNumBlocksPerSecond && external_delay_;
}
// Flag whether the linear echo estimate should be used.
linear_echo_estimate_ = usable_linear_estimate_ && !TransparentMode();
// Flag whether a sufficient number of filter updates has been done for the
// filter to perform well.
if (SaturatingEchoPath()) {
sufficient_filter_updates_ =
blocks_with_filter_adaptation_ >= 2 * kEchoPathChangeConvergenceBlocks;
} else {
sufficient_filter_updates_ =
blocks_with_filter_adaptation_ >= kEchoPathChangeConvergenceBlocks;
}
(!render_received_ || blocks_with_filter_adaptation_ >=
5 * kNumBlocksPerSecond);
// Update the room reverb estimate.
UpdateReverb(adaptive_filter_impulse_response);

3
modules/audio_processing/aec3/aec_state.h
View File

@ -156,8 +156,8 @@ class AecState {
bool capture_signal_saturation_ = false;
bool echo_saturation_ = false;
bool transparent_mode_ = false;
float previous_max_sample_ = 0.f;
std::array<float, kAdaptiveFilterLength> max_render_;
size_t max_render_index_ = 0;
bool force_zero_gain_ = false;
bool render_received_ = false;
size_t force_zero_gain_counter_ = 0;
@ -171,7 +171,6 @@ class AecState {
const EchoCanceller3Config config_;
float reverb_decay_;
bool saturating_echo_path_ = false;
int saturating_echo_path_counter_ = 0;
bool initial_state_ = true;
bool linear_echo_estimate_ = false;
bool sufficient_filter_updates_ = false;

2
modules/audio_processing/aec3/matched_filter.cc
View File

@ -376,7 +376,7 @@ void MatchedFilter::Update(const DownsampledRenderBuffer& render_buffer,
[](float a, float b) -> bool { return a * a < b * b; }));
// Update the lag estimates for the matched filter.
const float kMatchingFilterThreshold = 0.05f;
const float kMatchingFilterThreshold = 0.2f;
lag_estimates_[n] = LagEstimate(
error_sum_anchor - error_sum,
(lag_estimate > 2 && lag_estimate < (filters_[n].size() - 10) &&

41
modules/audio_processing/aec3/residual_echo_estimator.cc
View File

@ -108,29 +108,56 @@ void ResidualEchoEstimator::Estimate(
R2->fill((*std::max_element(R2->begin(), R2->end())) * 100.f);
}
} else {
const rtc::Optional<size_t> delay =
aec_state.ExternalDelay()
? (aec_state.FilterDelay() ? aec_state.FilterDelay()
: aec_state.ExternalDelay())
: rtc::Optional<size_t>();
// Estimate the echo generating signal power.
std::array<float, kFftLengthBy2Plus1> X2;
if (aec_state.ExternalDelay() && aec_state.FilterDelay()) {
RTC_DCHECK(delay);
const int delay_use = static_cast<int>(*delay);
// Computes the spectral power over the blocks surrounding the delay.
constexpr int kKnownDelayRenderWindowSize = 5;
// TODO(peah): Add lookahead since that was what was there initially.
static_assert(
kUnknownDelayRenderWindowSize >= kKnownDelayRenderWindowSize,
"Requirement to ensure that the render buffer is overrun");
EchoGeneratingPower(
render_buffer, std::max(0, delay_use - 1),
std::min(kKnownDelayRenderWindowSize - 1, delay_use + 1), &X2);
} else {
// Computes the spectral power over the latest blocks.
// TODO(peah): Add lookahead since that was what was there initially.
EchoGeneratingPower(render_buffer, 0, kUnknownDelayRenderWindowSize - 1,
&X2);
}
// Subtract the stationary noise power to avoid stationary noise causing
// excessive echo suppression.
if (!(aec_state.SaturatedEcho() || aec_state.SaturatingEchoPath())) {
std::transform(
X2.begin(), X2.end(), X2_noise_floor_.begin(), X2.begin(),
[](float a, float b) { return std::max(0.f, a - 10.f * b); });
}
NonLinearEstimate(
aec_state.SufficientFilterUpdates(),
aec_state.SaturatedEcho() && aec_state.SaturatingEchoPath(),
aec_state.SufficientFilterUpdates(), aec_state.SaturatedEcho(),
config_.ep_strength.bounded_erl, aec_state.TransparentMode(),
aec_state.InitialState(), X2, Y2, R2);
if (aec_state.ExternalDelay() && aec_state.FilterDelay() &&
aec_state.SaturatedEcho()) {
AddEchoReverb(*R2, aec_state.SaturatedEcho(),
std::min(static_cast<size_t>(kAdaptiveFilterLength),
delay.value_or(kAdaptiveFilterLength)),
aec_state.ReverbDecay(), R2);
}
}
// If the echo is deemed inaudible, set the residual echo to zero.
if (aec_state.InaudibleEcho() &&
(!(aec_state.SaturatedEcho() || aec_state.SaturatingEchoPath()))) {
if (aec_state.InaudibleEcho()) {
R2->fill(0.f);
R2_old_.fill(0.f);
R2_hold_counter_.fill(0.f);
@ -179,7 +206,7 @@ void ResidualEchoEstimator::NonLinearEstimate(
// Set echo path gains.
if (saturated_echo) {
// If the echo could be saturated, use a very conservative gain.
echo_path_gain_lf = echo_path_gain_mf = echo_path_gain_hf = 1000.f;
echo_path_gain_lf = echo_path_gain_mf = echo_path_gain_hf = 10000.f;
} else if (sufficient_filter_updates && !bounded_erl) {
// If the filter should have been able to converge, and no assumption is
// possible on the ERL, use a low gain.

22
modules/audio_processing/aec3/subtractor.cc
View File

@ -60,13 +60,11 @@ Subtractor::~Subtractor() = default;
void Subtractor::HandleEchoPathChange(
const EchoPathVariability& echo_path_variability) {
const auto full_reset = [&]() {
use_shadow_filter_frequency_response_ = false;
main_filter_.HandleEchoPathChange();
shadow_filter_.HandleEchoPathChange();
G_main_.HandleEchoPathChange(echo_path_variability);
G_shadow_.HandleEchoPathChange();
converged_filter_ = false;
converged_filter_counter_ = 0;
};
// TODO(peah): Add delay-change specific reset behavior.
@ -107,7 +105,8 @@ void Subtractor::Process(const RenderBuffer& render_buffer,
shadow_filter_.Filter(render_buffer, &S);
PredictionError(fft_, S, y, &e_shadow, &E_shadow, nullptr);
// Determine which frequency response should be used.
if (!converged_filter_) {
const auto sum_of_squares = [](float a, float b) { return a + b * b; };
const float e2_main =
std::accumulate(e_main.begin(), e_main.end(), 0.f, sum_of_squares);
@ -115,21 +114,8 @@ void Subtractor::Process(const RenderBuffer& render_buffer,
std::accumulate(e_shadow.begin(), e_shadow.end(), 0.f, sum_of_squares);
const float y2 = std::accumulate(y.begin(), y.end(), 0.f, sum_of_squares);
if (e2_main < e2_shadow && e2_main < 0.1 * y2) {
use_shadow_filter_frequency_response_ = false;
} else if (e2_shadow < e2_main && e2_shadow < 0.01 * y2) {
use_shadow_filter_frequency_response_ = true;
}
// Flag whether the filter has at some point converged.
// TODO(peah): Consider using a timeout for this.
if (!converged_filter_) {
if (y2 > kBlockSize * 100.f * 100.f) {
if (e2_main < 0.3 * y2) {
converged_filter_ = (++converged_filter_counter_) > 10;
} else {
converged_filter_counter_ = 0;
}
if (y2 > kBlockSize * 50.f * 50.f) {
converged_filter_ = (e2_main > 0.3 * y2 || e2_shadow > 0.1 * y2);
}
}

5
modules/audio_processing/aec3/subtractor.h
View File

@ -48,9 +48,6 @@ class Subtractor {
// Returns the block-wise frequency response for the main adaptive filter.
const std::vector<std::array<float, kFftLengthBy2Plus1>>&
FilterFrequencyResponse() const {
if (use_shadow_filter_frequency_response_) {
return shadow_filter_.FilterFrequencyResponse();
}
return main_filter_.FilterFrequencyResponse();
}
@ -71,8 +68,6 @@ class Subtractor {
MainFilterUpdateGain G_main_;
ShadowFilterUpdateGain G_shadow_;
bool converged_filter_ = false;
size_t converged_filter_counter_ = 0;
bool use_shadow_filter_frequency_response_ = false;
RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(Subtractor);
};

45
modules/audio_processing/aec3/suppression_gain.cc
View File

@ -126,14 +126,7 @@ void UpdateMaxGainIncrease(
float min_decreasing;
auto& param = config.gain_updates;
if (no_saturation_counter <= 10) {
max_increasing = param.saturation.max_inc;
max_decreasing = param.saturation.max_dec;
rate_increasing = param.saturation.rate_inc;
rate_decreasing = param.saturation.rate_dec;
min_increasing = param.saturation.min_inc;
min_decreasing = param.saturation.min_dec;
} else if (!linear_echo_estimate) {
if (linear_echo_estimate) {
max_increasing = param.nonlinear.max_inc;
max_decreasing = param.nonlinear.max_dec;
rate_increasing = param.nonlinear.rate_inc;
@ -147,13 +140,20 @@ void UpdateMaxGainIncrease(
rate_decreasing = param.low_noise.rate_dec;
min_increasing = param.low_noise.min_inc;
min_decreasing = param.low_noise.min_dec;
} else {
} else if (no_saturation_counter > 10) {
max_increasing = param.normal.max_inc;
max_decreasing = param.normal.max_dec;
rate_increasing = param.normal.rate_inc;
rate_decreasing = param.normal.rate_dec;
min_increasing = param.normal.min_inc;
min_decreasing = param.normal.min_dec;
} else {
max_increasing = param.saturation.max_inc;
max_decreasing = param.saturation.max_dec;
rate_increasing = param.saturation.rate_inc;
rate_decreasing = param.saturation.rate_dec;
min_increasing = param.saturation.min_inc;
min_decreasing = param.saturation.min_dec;
}
for (size_t k = 0; k < new_gain.size(); ++k) {
@ -186,29 +186,22 @@ void GainToNoAudibleEcho(
const std::array<float, kFftLengthBy2Plus1>& one_by_echo,
std::array<float, kFftLengthBy2Plus1>* gain) {
float nearend_masking_margin = 0.f;
if (saturated_echo) {
nearend_masking_margin = config.gain_mask.m2;
} else {
if (linear_echo_estimate) {
nearend_masking_margin =
low_noise_render ? config.gain_mask.m9 : config.gain_mask.m3;
low_noise_render
? config.gain_mask.m9
: (saturated_echo ? config.gain_mask.m2 : config.gain_mask.m3);
} else {
nearend_masking_margin = config.gain_mask.m7;
}
}
RTC_DCHECK_LE(0.f, nearend_masking_margin);
RTC_DCHECK_GT(1.f, nearend_masking_margin);
const float one_by_one_minus_nearend_masking_margin =
1.f / (1.0f - nearend_masking_margin);
float masker_margin;
if (saturated_echo || saturating_echo_path) {
masker_margin = 0.0001f;
} else {
masker_margin =
const float masker_margin =
linear_echo_estimate ? config.gain_mask.m1 : config.gain_mask.m8;
}
for (size_t k = 0; k < gain->size(); ++k) {
const float unity_gain_masker = std::max(nearend[k], masker[k]);
@ -306,7 +299,7 @@ void SuppressionGain::LowerBandGain(
const float min_echo_power =
low_noise_render ? config_.echo_audibility.low_render_limit
: config_.echo_audibility.normal_render_limit;
if (!saturating_echo_path) {
if (no_saturation_counter_ > 10) {
for (size_t k = 0; k < nearend.size(); ++k) {
const float denom = std::min(nearend[k], echo[k]);
min_gain[k] = denom > 0.f ? min_echo_power / denom : 1.f;
@ -319,12 +312,10 @@ void SuppressionGain::LowerBandGain(
// Compute the maximum gain by limiting the gain increase from the previous
// gain.
std::array<float, kFftLengthBy2Plus1> max_gain;
const float first_increase = saturated_echo || saturating_echo_path
? 0.00001f
: config_.gain_updates.floor_first_increase;
for (size_t k = 0; k < gain->size(); ++k) {
max_gain[k] = std::min(
std::max(last_gain_[k] * gain_increase_[k], first_increase), 1.f);
max_gain[k] = std::min(std::max(last_gain_[k] * gain_increase_[k],
config_.gain_updates.floor_first_increase),
1.f);
}
// Iteratively compute the gain required to attenuate the echo to a non
@ -333,7 +324,7 @@ void SuppressionGain::LowerBandGain(
for (int k = 0; k < 2; ++k) {
std::array<float, kFftLengthBy2Plus1> masker;
MaskingPower(config_, nearend, comfort_noise, last_masker_, *gain, &masker);
GainToNoAudibleEcho(config_, low_noise_render, no_saturation_counter_ > 10,
GainToNoAudibleEcho(config_, low_noise_render, saturated_echo,
saturating_echo_path, linear_echo_estimate, nearend,
echo, masker, min_gain, max_gain, one_by_echo, gain);
AdjustForExternalFilters(gain);

2
modules/audio_processing/include/audio_processing.h
View File

@ -1207,7 +1207,7 @@ struct EchoCanceller3Config {
GainChanges low_noise = {3.f, 3.f, 1.5f, 1.5f, 1.5f, 1.5f};
GainChanges normal = {2.f, 2.f, 1.5f, 1.5f, 1.2f, 1.2f};
GainChanges saturation = {1.5f, 1.5f, 1.2f, 1.2f, 1.1f, 1.1f};
GainChanges saturation = {1.2f, 1.2f, 1.5f, 1.5f, 1.f, 1.f};
GainChanges nonlinear = {1.5f, 1.5f, 1.2f, 1.2f, 1.1f, 1.1f};
float floor_first_increase = 0.0001f;