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Make the high frequency correction range depend on the target angle

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Depends on this CL: https://codereview.webrtc.org/1388033002/

Review URL: https://codereview.webrtc.org/1395453004

Cr-Commit-Position: refs/heads/master@{#10331}
This commit is contained in:
aluebs
2015-10-19 19:49:30 -07:00
committed by Commit bot
parent 4a66e4a4d8
commit 1897f77806
2 changed files with 33 additions and 24 deletions
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56
webrtc/modules/audio_processing/beamformer/nonlinear_beamformer.cc
View File

@ -61,11 +61,6 @@ const float kMaskFrequencySmoothAlpha = 0.6f;
const int kLowMeanStartHz = 200;
const int kLowMeanEndHz = 400;
// TODO(aluebs): Make the high frequency correction range depend on the target
// angle.
const int kHighMeanStartHz = 3000;
const int kHighMeanEndHz = 5000;
// Range limiter for subtractive terms in the nominator and denominator of the
// postfilter expression. It handles the scenario mismatch between the true and
// model sources (target and interference).
@ -207,25 +202,7 @@ void NonlinearBeamformer::Initialize(int chunk_size_ms, int sample_rate_hz) {
chunk_length_ =
static_cast<size_t>(sample_rate_hz / (1000.f / chunk_size_ms));
sample_rate_hz_ = sample_rate_hz;
low_mean_start_bin_ = Round(kLowMeanStartHz * kFftSize / sample_rate_hz_);
low_mean_end_bin_ = Round(kLowMeanEndHz * kFftSize / sample_rate_hz_);
high_mean_start_bin_ = Round(kHighMeanStartHz * kFftSize / sample_rate_hz_);
high_mean_end_bin_ = Round(kHighMeanEndHz * kFftSize / sample_rate_hz_);
// These bin indexes determine the regions over which a mean is taken. This
// is applied as a constant value over the adjacent end "frequency correction"
// regions.
//
// low_mean_start_bin_ high_mean_start_bin_
// v v constant
// |----------------|--------|----------------|-------|----------------|
// constant ^ ^
// low_mean_end_bin_ high_mean_end_bin_
//
RTC_DCHECK_GT(low_mean_start_bin_, 0U);
RTC_DCHECK_LT(low_mean_start_bin_, low_mean_end_bin_);
RTC_DCHECK_LT(low_mean_end_bin_, high_mean_end_bin_);
RTC_DCHECK_LT(high_mean_start_bin_, high_mean_end_bin_);
RTC_DCHECK_LT(high_mean_end_bin_, kNumFreqBins - 1);
InitFrequencyCorrectionRanges();
high_pass_postfilter_mask_ = 1.f;
is_target_present_ = false;
@ -261,6 +238,37 @@ void NonlinearBeamformer::Initialize(int chunk_size_ms, int sample_rate_hz) {
}
}
void NonlinearBeamformer::InitFrequencyCorrectionRanges() {
const float kAliasingFreqHz =
kSpeedOfSoundMeterSeconds /
(min_mic_spacing_ * (1.f + std::abs(std::cos(kTargetAngleRadians))));
const float kHighMeanStartHz = std::min(0.5f * kAliasingFreqHz,
sample_rate_hz_ / 2.f);
const float kHighMeanEndHz = std::min(0.75f * kAliasingFreqHz,
sample_rate_hz_ / 2.f);
low_mean_start_bin_ = Round(kLowMeanStartHz * kFftSize / sample_rate_hz_);
low_mean_end_bin_ = Round(kLowMeanEndHz * kFftSize / sample_rate_hz_);
high_mean_start_bin_ = Round(kHighMeanStartHz * kFftSize / sample_rate_hz_);
high_mean_end_bin_ = Round(kHighMeanEndHz * kFftSize / sample_rate_hz_);
// These bin indexes determine the regions over which a mean is taken. This
// is applied as a constant value over the adjacent end "frequency correction"
// regions.
//
// low_mean_start_bin_ high_mean_start_bin_
// v v constant
// |----------------|--------|----------------|-------|----------------|
// constant ^ ^
// low_mean_end_bin_ high_mean_end_bin_
//
RTC_DCHECK_GT(low_mean_start_bin_, 0U);
RTC_DCHECK_LT(low_mean_start_bin_, low_mean_end_bin_);
RTC_DCHECK_LT(low_mean_end_bin_, high_mean_end_bin_);
RTC_DCHECK_LT(high_mean_start_bin_, high_mean_end_bin_);
RTC_DCHECK_LT(high_mean_end_bin_, kNumFreqBins - 1);
}
void NonlinearBeamformer::InitInterfAngles() {
const float kAwayRadians =
std::min(static_cast<float>(M_PI),

1
webrtc/modules/audio_processing/beamformer/nonlinear_beamformer.h
View File

@ -66,6 +66,7 @@ class NonlinearBeamformer
typedef ComplexMatrix<float> ComplexMatrixF;
typedef complex<float> complex_f;
void InitFrequencyCorrectionRanges();
void InitInterfAngles();
void InitDelaySumMasks();
void InitTargetCovMats();