Index: webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.cc |
diff --git a/webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.cc b/webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.cc |
index 6a25104bdd4ef28de09631a32dc8b7e2265b665f..932eff1091b689d5752ea228eb746a5bd05d3597 100644 |
--- a/webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.cc |
+++ b/webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.cc |
@@ -8,13 +8,6 @@ |
* be found in the AUTHORS file in the root of the source tree. |
*/ |
-// |
-// Implements core class for intelligibility enhancer. |
-// |
-// Details of the model and algorithm can be found in the original paper: |
-// http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6882788 |
-// |
- |
#include "webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.h" |
#include <cmath> |
@@ -34,16 +27,13 @@ |
const int IntelligibilityEnhancer::kErbResolution = 2; |
const int IntelligibilityEnhancer::kWindowSizeMs = 2; |
-const int IntelligibilityEnhancer::kChunkSizeMs = 10; // Size provided by APM. |
+// The size of the chunk provided by APM, in milliseconds. |
+const int IntelligibilityEnhancer::kChunkSizeMs = 10; |
const int IntelligibilityEnhancer::kAnalyzeRate = 800; |
const int IntelligibilityEnhancer::kVarianceRate = 2; |
const float IntelligibilityEnhancer::kClipFreq = 200.0f; |
const float IntelligibilityEnhancer::kConfigRho = 0.02f; |
const float IntelligibilityEnhancer::kKbdAlpha = 1.5f; |
- |
-// To disable gain update smoothing, set gain limit to be VERY high. |
-// TODO(ekmeyerson): Add option to disable gain smoothing altogether |
-// to avoid the extra computation. |
const float IntelligibilityEnhancer::kGainChangeLimit = 0.0125f; |
using VarianceType = intelligibility::VarianceArray::StepType; |
@@ -51,14 +41,12 @@ |
IntelligibilityEnhancer::TransformCallback::TransformCallback( |
IntelligibilityEnhancer* parent, |
IntelligibilityEnhancer::AudioSource source) |
- : parent_(parent), source_(source) { |
-} |
+ : parent_(parent), |
+ source_(source) {} |
void IntelligibilityEnhancer::TransformCallback::ProcessAudioBlock( |
const complex<float>* const* in_block, |
- int in_channels, |
- int frames, |
- int /* out_channels */, |
+ int in_channels, int frames, int /* out_channels */, |
complex<float>* const* out_block) { |
DCHECK_EQ(parent_->freqs_, frames); |
for (int i = 0; i < in_channels; ++i) { |
@@ -69,14 +57,13 @@ |
IntelligibilityEnhancer::IntelligibilityEnhancer(int erb_resolution, |
int sample_rate_hz, |
int channels, |
- int cv_type, |
- float cv_alpha, |
+ int cv_type, float cv_alpha, |
int cv_win, |
int analysis_rate, |
int variance_rate, |
float gain_limit) |
- : freqs_(RealFourier::ComplexLength( |
- RealFourier::FftOrder(sample_rate_hz * kWindowSizeMs / 1000))), |
+ : freqs_(RealFourier::ComplexLength(RealFourier::FftOrder( |
+ sample_rate_hz * kWindowSizeMs / 1000))), |
window_size_(1 << RealFourier::FftOrder(freqs_)), |
chunk_length_(sample_rate_hz * kChunkSizeMs / 1000), |
bank_size_(GetBankSize(sample_rate_hz, erb_resolution)), |
@@ -85,9 +72,7 @@ |
channels_(channels), |
analysis_rate_(analysis_rate), |
variance_rate_(variance_rate), |
- clear_variance_(freqs_, |
- static_cast<VarianceType>(cv_type), |
- cv_win, |
+ clear_variance_(freqs_, static_cast<VarianceType>(cv_type), cv_win, |
cv_alpha), |
noise_variance_(freqs_, VarianceType::kStepInfinite, 475, 0.01f), |
filtered_clear_var_(new float[bank_size_]), |
@@ -98,51 +83,58 @@ |
gains_eq_(new float[bank_size_]), |
gain_applier_(freqs_, gain_limit), |
temp_out_buffer_(nullptr), |
- input_audio_(new float* [channels]), |
+ input_audio_(new float*[channels]), |
kbd_window_(new float[window_size_]), |
render_callback_(this, AudioSource::kRenderStream), |
capture_callback_(this, AudioSource::kCaptureStream), |
block_count_(0), |
analysis_step_(0), |
- vad_high_(WebRtcVad_Create()), |
- vad_low_(WebRtcVad_Create()), |
+ vad_high_(nullptr), |
+ vad_low_(nullptr), |
vad_tmp_buffer_(new int16_t[chunk_length_]) { |
DCHECK_LE(kConfigRho, 1.0f); |
CreateErbBank(); |
+ WebRtcVad_Create(&vad_high_); |
WebRtcVad_Init(vad_high_); |
- WebRtcVad_set_mode(vad_high_, 0); // High likelihood of speech. |
+ WebRtcVad_set_mode(vad_high_, 0); // high likelihood of speech |
+ WebRtcVad_Create(&vad_low_); |
WebRtcVad_Init(vad_low_); |
- WebRtcVad_set_mode(vad_low_, 3); // Low likelihood of speech. |
- |
- temp_out_buffer_ = static_cast<float**>( |
- malloc(sizeof(*temp_out_buffer_) * channels_ + |
- sizeof(**temp_out_buffer_) * chunk_length_ * channels_)); |
+ WebRtcVad_set_mode(vad_low_, 3); // low likelihood of speech |
+ |
+ temp_out_buffer_ = static_cast<float**>(malloc( |
+ sizeof(*temp_out_buffer_) * channels_ + |
+ sizeof(**temp_out_buffer_) * chunk_length_ * channels_)); |
for (int i = 0; i < channels_; ++i) { |
- temp_out_buffer_[i] = |
- reinterpret_cast<float*>(temp_out_buffer_ + channels_) + |
- chunk_length_ * i; |
- } |
- |
- // Assumes all rho equal. |
+ temp_out_buffer_[i] = reinterpret_cast<float*>(temp_out_buffer_ + channels_) |
+ + chunk_length_ * i; |
+ } |
+ |
for (int i = 0; i < bank_size_; ++i) { |
rho_[i] = kConfigRho * kConfigRho; |
} |
float freqs_khz = kClipFreq / 1000.0f; |
- int erb_index = static_cast<int>(ceilf( |
- 11.17f * logf((freqs_khz + 0.312f) / (freqs_khz + 14.6575f)) + 43.0f)); |
+ int erb_index = static_cast<int>(ceilf(11.17f * logf((freqs_khz + 0.312f) / |
+ (freqs_khz + 14.6575f)) |
+ + 43.0f)); |
start_freq_ = max(1, erb_index * kErbResolution); |
WindowGenerator::KaiserBesselDerived(kKbdAlpha, window_size_, |
kbd_window_.get()); |
- render_mangler_.reset(new LappedTransform( |
- channels_, channels_, chunk_length_, kbd_window_.get(), window_size_, |
- window_size_ / 2, &render_callback_)); |
- capture_mangler_.reset(new LappedTransform( |
- channels_, channels_, chunk_length_, kbd_window_.get(), window_size_, |
- window_size_ / 2, &capture_callback_)); |
+ render_mangler_.reset(new LappedTransform(channels_, channels_, |
+ chunk_length_, |
+ kbd_window_.get(), |
+ window_size_, |
+ window_size_ / 2, |
+ &render_callback_)); |
+ capture_mangler_.reset(new LappedTransform(channels_, channels_, |
+ chunk_length_, |
+ kbd_window_.get(), |
+ window_size_, |
+ window_size_ / 2, |
+ &capture_callback_)); |
} |
IntelligibilityEnhancer::~IntelligibilityEnhancer() { |
@@ -158,9 +150,7 @@ |
has_voice_low_ = WebRtcVad_Process(vad_low_, sample_rate_hz_, |
vad_tmp_buffer_.get(), chunk_length_) == 1; |
- // Process and enhance chunk of |audio| |
render_mangler_->ProcessChunk(audio, temp_out_buffer_); |
- |
for (int i = 0; i < channels_; ++i) { |
memcpy(audio[i], temp_out_buffer_[i], |
chunk_length_ * sizeof(**temp_out_buffer_)); |
@@ -171,25 +161,21 @@ |
for (int i = 0; i < chunk_length_; ++i) { |
vad_tmp_buffer_[i] = (int16_t)audio[0][i]; |
} |
- // TODO(bercic): The VAD was always detecting voice in the noise stream, |
- // no matter what the aggressiveness, so it was temporarily disabled here. |
- |
- #if 0 |
- if (WebRtcVad_Process(vad_high_, sample_rate_hz_, vad_tmp_buffer_.get(), |
- chunk_length_) == 1) { |
- printf("capture HAS speech\n"); |
- return; |
- } |
- printf("capture NO speech\n"); |
- #endif |
- |
+ // TODO(bercic): the VAD was always detecting voice in the noise stream, |
+ // no matter what the aggressiveness, so it was temporarily disabled here |
+ |
+ //if (WebRtcVad_Process(vad_high_, sample_rate_hz_, vad_tmp_buffer_.get(), |
+ // chunk_length_) == 1) { |
+ // printf("capture HAS speech\n"); |
+ // return; |
+ //} |
+ //printf("capture NO speech\n"); |
capture_mangler_->ProcessChunk(audio, temp_out_buffer_); |
} |
void IntelligibilityEnhancer::DispatchAudio( |
IntelligibilityEnhancer::AudioSource source, |
- const complex<float>* in_block, |
- complex<float>* out_block) { |
+ const complex<float>* in_block, complex<float>* out_block) { |
switch (source) { |
case kRenderStream: |
ProcessClearBlock(in_block, out_block); |
@@ -210,9 +196,6 @@ |
return; |
} |
- // For now, always assumes enhancement is necessary. |
- // TODO(ekmeyerson): Change to only enhance if necessary, |
- // based on experiments with different cutoffs. |
if (has_voice_low_ || true) { |
clear_variance_.Step(in_block, false); |
power_target = std::accumulate(clear_variance_.variance(), |
@@ -238,25 +221,23 @@ |
FilterVariance(clear_variance_.variance(), filtered_clear_var_.get()); |
FilterVariance(noise_variance_.variance(), filtered_noise_var_.get()); |
- // Bisection search for optimal |lambda| |
+ /* lambda binary search */ |
float lambda_bot = -1.0f, lambda_top = -10e-18f, lambda; |
float power_bot, power_top, power; |
- SolveForGainsGivenLambda(lambda_top, start_freq_, gains_eq_.get()); |
- power_top = |
- DotProduct(gains_eq_.get(), filtered_clear_var_.get(), bank_size_); |
- SolveForGainsGivenLambda(lambda_bot, start_freq_, gains_eq_.get()); |
- power_bot = |
- DotProduct(gains_eq_.get(), filtered_clear_var_.get(), bank_size_); |
+ SolveEquation14(lambda_top, start_freq_, gains_eq_.get()); |
+ power_top = DotProduct(gains_eq_.get(), filtered_clear_var_.get(), |
+ bank_size_); |
+ SolveEquation14(lambda_bot, start_freq_, gains_eq_.get()); |
+ power_bot = DotProduct(gains_eq_.get(), filtered_clear_var_.get(), |
+ bank_size_); |
DCHECK(power_target >= power_bot && power_target <= power_top); |
- float power_ratio = 2.0f; // Ratio of achieved power to target power. |
- const float kConvergeThresh = 0.001f; // TODO(ekmeyerson): Find best values |
- const int kMaxIters = 100; // for these, based on experiments. |
+ float power_ratio = 2.0f; |
int iters = 0; |
- while (fabs(power_ratio - 1.0f) > kConvergeThresh && iters <= kMaxIters) { |
+ while (fabs(power_ratio - 1.0f) > 0.001f && iters <= 100) { |
lambda = lambda_bot + (lambda_top - lambda_bot) / 2.0f; |
- SolveForGainsGivenLambda(lambda, start_freq_, gains_eq_.get()); |
+ SolveEquation14(lambda, start_freq_, gains_eq_.get()); |
power = DotProduct(gains_eq_.get(), filtered_clear_var_.get(), bank_size_); |
if (power < power_target) { |
lambda_bot = lambda; |
@@ -267,7 +248,7 @@ |
++iters; |
} |
- // (ERB gain) = filterbank' * (freq gain) |
+ /* b = filterbank' * b */ |
float* gains = gain_applier_.target(); |
for (int i = 0; i < freqs_; ++i) { |
gains[i] = 0.0f; |
@@ -284,8 +265,8 @@ |
int IntelligibilityEnhancer::GetBankSize(int sample_rate, int erb_resolution) { |
float freq_limit = sample_rate / 2000.0f; |
- int erb_scale = ceilf( |
- 11.17f * logf((freq_limit + 0.312f) / (freq_limit + 14.6575f)) + 43.0f); |
+ int erb_scale = ceilf(11.17f * logf((freq_limit + 0.312f) / |
+ (freq_limit + 14.6575f)) + 43.0f); |
return erb_scale * erb_resolution; |
} |
@@ -302,29 +283,29 @@ |
center_freqs_[i] *= 0.5f * sample_rate_hz_ / last_center_freq; |
} |
- filter_bank_ = static_cast<float**>( |
- malloc(sizeof(*filter_bank_) * bank_size_ + |
- sizeof(**filter_bank_) * freqs_ * bank_size_)); |
- for (int i = 0; i < bank_size_; ++i) { |
- filter_bank_[i] = |
- reinterpret_cast<float*>(filter_bank_ + bank_size_) + freqs_ * i; |
+ filter_bank_ = static_cast<float**>(malloc( |
+ sizeof(*filter_bank_) * bank_size_ + |
+ sizeof(**filter_bank_) * freqs_ * bank_size_)); |
+ for (int i = 0; i < bank_size_; ++i) { |
+ filter_bank_[i] = reinterpret_cast<float*>(filter_bank_ + bank_size_) + |
+ freqs_ * i; |
} |
for (int i = 1; i <= bank_size_; ++i) { |
int lll, ll, rr, rrr; |
lll = round(center_freqs_[max(1, i - lf) - 1] * freqs_ / |
- (0.5f * sample_rate_hz_)); |
- ll = |
- round(center_freqs_[max(1, i) - 1] * freqs_ / (0.5f * sample_rate_hz_)); |
+ (0.5f * sample_rate_hz_)); |
+ ll = round(center_freqs_[max(1, i ) - 1] * freqs_ / |
+ (0.5f * sample_rate_hz_)); |
lll = min(freqs_, max(lll, 1)) - 1; |
- ll = min(freqs_, max(ll, 1)) - 1; |
+ ll = min(freqs_, max(ll, 1)) - 1; |
rrr = round(center_freqs_[min(bank_size_, i + rf) - 1] * freqs_ / |
- (0.5f * sample_rate_hz_)); |
- rr = round(center_freqs_[min(bank_size_, i + 1) - 1] * freqs_ / |
- (0.5f * sample_rate_hz_)); |
+ (0.5f * sample_rate_hz_)); |
+ rr = round(center_freqs_[min(bank_size_, i + 1) - 1] * freqs_ / |
+ (0.5f * sample_rate_hz_)); |
rrr = min(freqs_, max(rrr, 1)) - 1; |
- rr = min(freqs_, max(rr, 1)) - 1; |
+ rr = min(freqs_, max(rr, 1)) - 1; |
float step, element; |
@@ -357,9 +338,8 @@ |
} |
} |
-void IntelligibilityEnhancer::SolveForGainsGivenLambda(float lambda, |
- int start_freq, |
- float* sols) { |
+void IntelligibilityEnhancer::SolveEquation14(float lambda, int start_freq, |
+ float* sols) { |
bool quadratic = (kConfigRho < 1.0f); |
const float* var_x0 = filtered_clear_var_.get(); |
const float* var_n0 = filtered_noise_var_.get(); |
@@ -367,17 +347,15 @@ |
for (int n = 0; n < start_freq; ++n) { |
sols[n] = 1.0f; |
} |
- |
- // Analytic solution for optimal gains. See paper for derivation. |
for (int n = start_freq - 1; n < bank_size_; ++n) { |
float alpha0, beta0, gamma0; |
gamma0 = 0.5f * rho_[n] * var_x0[n] * var_n0[n] + |
- lambda * var_x0[n] * var_n0[n] * var_n0[n]; |
+ lambda * var_x0[n] * var_n0[n] * var_n0[n]; |
beta0 = lambda * var_x0[n] * (2 - rho_[n]) * var_x0[n] * var_n0[n]; |
if (quadratic) { |
alpha0 = lambda * var_x0[n] * (1 - rho_[n]) * var_x0[n] * var_x0[n]; |
- sols[n] = |
- (-beta0 - sqrtf(beta0 * beta0 - 4 * alpha0 * gamma0)) / (2 * alpha0); |
+ sols[n] = (-beta0 - sqrtf(beta0 * beta0 - 4 * alpha0 * gamma0)) |
+ / (2 * alpha0); |
} else { |
sols[n] = -gamma0 / beta0; |
} |
@@ -391,9 +369,8 @@ |
} |
} |
-float IntelligibilityEnhancer::DotProduct(const float* a, |
- const float* b, |
- int length) { |
+float IntelligibilityEnhancer::DotProduct(const float* a, const float* b, |
+ int length) { |
float ret = 0.0f; |
for (int i = 0; i < length; ++i) { |
@@ -403,3 +380,4 @@ |
} |
} // namespace webrtc |
+ |