Initial SIE commit: migrating existing code
Moved exact existing intelligibility enhancement implementation into new repository for reference when making further changes. Note: this cl does not add these files to any gyp. Original cl is at https://webrtc-codereview.appspot.com/52719004/ . TBR=aluebs@webrtc.org Review URL: https://codereview.webrtc.org/1177953006. Cr-Commit-Position: refs/heads/master@{#9441}
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/*
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* Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#include "webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.h"
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#include <cmath>
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#include <cstdlib>
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#include <algorithm>
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#include "webrtc/base/checks.h"
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#include "webrtc/common_audio/vad/include/webrtc_vad.h"
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#include "webrtc/common_audio/window_generator.h"
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using std::complex;
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using std::max;
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using std::min;
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namespace webrtc {
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const int IntelligibilityEnhancer::kErbResolution = 2;
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const int IntelligibilityEnhancer::kWindowSizeMs = 2;
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// The size of the chunk provided by APM, in milliseconds.
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const int IntelligibilityEnhancer::kChunkSizeMs = 10;
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const int IntelligibilityEnhancer::kAnalyzeRate = 800;
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const int IntelligibilityEnhancer::kVarianceRate = 2;
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const float IntelligibilityEnhancer::kClipFreq = 200.0f;
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const float IntelligibilityEnhancer::kConfigRho = 0.02f;
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const float IntelligibilityEnhancer::kKbdAlpha = 1.5f;
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const float IntelligibilityEnhancer::kGainChangeLimit = 0.0125f;
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using VarianceType = intelligibility::VarianceArray::StepType;
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IntelligibilityEnhancer::TransformCallback::TransformCallback(
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IntelligibilityEnhancer* parent,
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IntelligibilityEnhancer::AudioSource source)
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: parent_(parent),
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source_(source) {}
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void IntelligibilityEnhancer::TransformCallback::ProcessAudioBlock(
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const complex<float>* const* in_block,
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int in_channels, int frames, int /* out_channels */,
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complex<float>* const* out_block) {
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DCHECK_EQ(parent_->freqs_, frames);
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for (int i = 0; i < in_channels; ++i) {
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parent_->DispatchAudio(source_, in_block[i], out_block[i]);
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}
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}
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IntelligibilityEnhancer::IntelligibilityEnhancer(int erb_resolution,
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int sample_rate_hz,
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int channels,
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int cv_type, float cv_alpha,
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int cv_win,
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int analysis_rate,
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int variance_rate,
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float gain_limit)
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: freqs_(RealFourier::ComplexLength(RealFourier::FftOrder(
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sample_rate_hz * kWindowSizeMs / 1000))),
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window_size_(1 << RealFourier::FftOrder(freqs_)),
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chunk_length_(sample_rate_hz * kChunkSizeMs / 1000),
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bank_size_(GetBankSize(sample_rate_hz, erb_resolution)),
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sample_rate_hz_(sample_rate_hz),
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erb_resolution_(erb_resolution),
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channels_(channels),
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analysis_rate_(analysis_rate),
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variance_rate_(variance_rate),
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clear_variance_(freqs_, static_cast<VarianceType>(cv_type), cv_win,
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cv_alpha),
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noise_variance_(freqs_, VarianceType::kStepInfinite, 475, 0.01f),
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filtered_clear_var_(new float[bank_size_]),
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filtered_noise_var_(new float[bank_size_]),
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filter_bank_(nullptr),
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center_freqs_(new float[bank_size_]),
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rho_(new float[bank_size_]),
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gains_eq_(new float[bank_size_]),
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gain_applier_(freqs_, gain_limit),
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temp_out_buffer_(nullptr),
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input_audio_(new float*[channels]),
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kbd_window_(new float[window_size_]),
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render_callback_(this, AudioSource::kRenderStream),
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capture_callback_(this, AudioSource::kCaptureStream),
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block_count_(0),
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analysis_step_(0),
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vad_high_(nullptr),
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vad_low_(nullptr),
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vad_tmp_buffer_(new int16_t[chunk_length_]) {
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DCHECK_LE(kConfigRho, 1.0f);
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CreateErbBank();
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WebRtcVad_Create(&vad_high_);
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WebRtcVad_Init(vad_high_);
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WebRtcVad_set_mode(vad_high_, 0); // high likelihood of speech
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WebRtcVad_Create(&vad_low_);
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WebRtcVad_Init(vad_low_);
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WebRtcVad_set_mode(vad_low_, 3); // low likelihood of speech
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temp_out_buffer_ = static_cast<float**>(malloc(
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sizeof(*temp_out_buffer_) * channels_ +
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sizeof(**temp_out_buffer_) * chunk_length_ * channels_));
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for (int i = 0; i < channels_; ++i) {
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temp_out_buffer_[i] = reinterpret_cast<float*>(temp_out_buffer_ + channels_)
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+ chunk_length_ * i;
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}
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for (int i = 0; i < bank_size_; ++i) {
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rho_[i] = kConfigRho * kConfigRho;
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}
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float freqs_khz = kClipFreq / 1000.0f;
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int erb_index = static_cast<int>(ceilf(11.17f * logf((freqs_khz + 0.312f) /
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(freqs_khz + 14.6575f))
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+ 43.0f));
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start_freq_ = max(1, erb_index * kErbResolution);
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WindowGenerator::KaiserBesselDerived(kKbdAlpha, window_size_,
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kbd_window_.get());
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render_mangler_.reset(new LappedTransform(channels_, channels_,
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chunk_length_,
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kbd_window_.get(),
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window_size_,
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window_size_ / 2,
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&render_callback_));
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capture_mangler_.reset(new LappedTransform(channels_, channels_,
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chunk_length_,
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kbd_window_.get(),
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window_size_,
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window_size_ / 2,
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&capture_callback_));
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}
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IntelligibilityEnhancer::~IntelligibilityEnhancer() {
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WebRtcVad_Free(vad_low_);
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WebRtcVad_Free(vad_high_);
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free(filter_bank_);
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}
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void IntelligibilityEnhancer::ProcessRenderAudio(float* const* audio) {
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for (int i = 0; i < chunk_length_; ++i) {
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vad_tmp_buffer_[i] = (int16_t)audio[0][i];
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}
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has_voice_low_ = WebRtcVad_Process(vad_low_, sample_rate_hz_,
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vad_tmp_buffer_.get(), chunk_length_) == 1;
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render_mangler_->ProcessChunk(audio, temp_out_buffer_);
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for (int i = 0; i < channels_; ++i) {
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memcpy(audio[i], temp_out_buffer_[i],
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chunk_length_ * sizeof(**temp_out_buffer_));
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}
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}
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void IntelligibilityEnhancer::ProcessCaptureAudio(float* const* audio) {
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for (int i = 0; i < chunk_length_; ++i) {
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vad_tmp_buffer_[i] = (int16_t)audio[0][i];
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}
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// TODO(bercic): the VAD was always detecting voice in the noise stream,
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// no matter what the aggressiveness, so it was temporarily disabled here
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//if (WebRtcVad_Process(vad_high_, sample_rate_hz_, vad_tmp_buffer_.get(),
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// chunk_length_) == 1) {
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// printf("capture HAS speech\n");
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// return;
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//}
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//printf("capture NO speech\n");
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capture_mangler_->ProcessChunk(audio, temp_out_buffer_);
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}
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void IntelligibilityEnhancer::DispatchAudio(
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IntelligibilityEnhancer::AudioSource source,
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const complex<float>* in_block, complex<float>* out_block) {
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switch (source) {
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case kRenderStream:
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ProcessClearBlock(in_block, out_block);
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break;
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case kCaptureStream:
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ProcessNoiseBlock(in_block, out_block);
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break;
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}
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}
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void IntelligibilityEnhancer::ProcessClearBlock(const complex<float>* in_block,
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complex<float>* out_block) {
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float power_target;
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if (block_count_ < 2) {
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memset(out_block, 0, freqs_ * sizeof(*out_block));
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++block_count_;
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return;
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}
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if (has_voice_low_ || true) {
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clear_variance_.Step(in_block, false);
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power_target = std::accumulate(clear_variance_.variance(),
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clear_variance_.variance() + freqs_, 0.0f);
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if (block_count_ % analysis_rate_ == analysis_rate_ - 1) {
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AnalyzeClearBlock(power_target);
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++analysis_step_;
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if (analysis_step_ == variance_rate_) {
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analysis_step_ = 0;
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clear_variance_.Clear();
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noise_variance_.Clear();
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}
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}
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++block_count_;
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}
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/* efidata(n,:) = sqrt(b(n)) * fidata(n,:) */
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gain_applier_.Apply(in_block, out_block);
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}
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void IntelligibilityEnhancer::AnalyzeClearBlock(float power_target) {
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FilterVariance(clear_variance_.variance(), filtered_clear_var_.get());
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FilterVariance(noise_variance_.variance(), filtered_noise_var_.get());
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/* lambda binary search */
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float lambda_bot = -1.0f, lambda_top = -10e-18f, lambda;
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float power_bot, power_top, power;
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SolveEquation14(lambda_top, start_freq_, gains_eq_.get());
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power_top = DotProduct(gains_eq_.get(), filtered_clear_var_.get(),
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bank_size_);
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SolveEquation14(lambda_bot, start_freq_, gains_eq_.get());
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power_bot = DotProduct(gains_eq_.get(), filtered_clear_var_.get(),
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bank_size_);
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DCHECK(power_target >= power_bot && power_target <= power_top);
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float power_ratio = 2.0f;
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int iters = 0;
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while (fabs(power_ratio - 1.0f) > 0.001f && iters <= 100) {
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lambda = lambda_bot + (lambda_top - lambda_bot) / 2.0f;
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SolveEquation14(lambda, start_freq_, gains_eq_.get());
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power = DotProduct(gains_eq_.get(), filtered_clear_var_.get(), bank_size_);
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if (power < power_target) {
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lambda_bot = lambda;
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} else {
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lambda_top = lambda;
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}
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power_ratio = fabs(power / power_target);
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++iters;
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}
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/* b = filterbank' * b */
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float* gains = gain_applier_.target();
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for (int i = 0; i < freqs_; ++i) {
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gains[i] = 0.0f;
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for (int j = 0; j < bank_size_; ++j) {
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gains[i] = fmaf(filter_bank_[j][i], gains_eq_[j], gains[i]);
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}
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}
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}
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void IntelligibilityEnhancer::ProcessNoiseBlock(const complex<float>* in_block,
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complex<float>* /*out_block*/) {
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noise_variance_.Step(in_block);
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}
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int IntelligibilityEnhancer::GetBankSize(int sample_rate, int erb_resolution) {
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float freq_limit = sample_rate / 2000.0f;
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int erb_scale = ceilf(11.17f * logf((freq_limit + 0.312f) /
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(freq_limit + 14.6575f)) + 43.0f);
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return erb_scale * erb_resolution;
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}
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void IntelligibilityEnhancer::CreateErbBank() {
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int lf = 1, rf = 4;
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for (int i = 0; i < bank_size_; ++i) {
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float abs_temp = fabsf((i + 1.0f) / static_cast<float>(erb_resolution_));
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center_freqs_[i] = 676170.4f / (47.06538f - expf(0.08950404f * abs_temp));
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center_freqs_[i] -= 14678.49f;
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}
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float last_center_freq = center_freqs_[bank_size_ - 1];
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for (int i = 0; i < bank_size_; ++i) {
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center_freqs_[i] *= 0.5f * sample_rate_hz_ / last_center_freq;
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}
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filter_bank_ = static_cast<float**>(malloc(
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sizeof(*filter_bank_) * bank_size_ +
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sizeof(**filter_bank_) * freqs_ * bank_size_));
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for (int i = 0; i < bank_size_; ++i) {
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filter_bank_[i] = reinterpret_cast<float*>(filter_bank_ + bank_size_) +
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freqs_ * i;
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}
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for (int i = 1; i <= bank_size_; ++i) {
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int lll, ll, rr, rrr;
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lll = round(center_freqs_[max(1, i - lf) - 1] * freqs_ /
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(0.5f * sample_rate_hz_));
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ll = round(center_freqs_[max(1, i ) - 1] * freqs_ /
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(0.5f * sample_rate_hz_));
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lll = min(freqs_, max(lll, 1)) - 1;
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ll = min(freqs_, max(ll, 1)) - 1;
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rrr = round(center_freqs_[min(bank_size_, i + rf) - 1] * freqs_ /
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(0.5f * sample_rate_hz_));
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rr = round(center_freqs_[min(bank_size_, i + 1) - 1] * freqs_ /
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(0.5f * sample_rate_hz_));
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rrr = min(freqs_, max(rrr, 1)) - 1;
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rr = min(freqs_, max(rr, 1)) - 1;
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float step, element;
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step = 1.0f / (ll - lll);
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element = 0.0f;
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for (int j = lll; j <= ll; ++j) {
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filter_bank_[i - 1][j] = element;
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element += step;
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}
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step = 1.0f / (rrr - rr);
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element = 1.0f;
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for (int j = rr; j <= rrr; ++j) {
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filter_bank_[i - 1][j] = element;
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element -= step;
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}
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for (int j = ll; j <= rr; ++j) {
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filter_bank_[i - 1][j] = 1.0f;
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}
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}
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float sum;
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for (int i = 0; i < freqs_; ++i) {
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sum = 0.0f;
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for (int j = 0; j < bank_size_; ++j) {
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sum += filter_bank_[j][i];
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}
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for (int j = 0; j < bank_size_; ++j) {
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filter_bank_[j][i] /= sum;
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}
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}
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}
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void IntelligibilityEnhancer::SolveEquation14(float lambda, int start_freq,
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float* sols) {
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bool quadratic = (kConfigRho < 1.0f);
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const float* var_x0 = filtered_clear_var_.get();
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const float* var_n0 = filtered_noise_var_.get();
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for (int n = 0; n < start_freq; ++n) {
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sols[n] = 1.0f;
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}
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for (int n = start_freq - 1; n < bank_size_; ++n) {
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float alpha0, beta0, gamma0;
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gamma0 = 0.5f * rho_[n] * var_x0[n] * var_n0[n] +
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lambda * var_x0[n] * var_n0[n] * var_n0[n];
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beta0 = lambda * var_x0[n] * (2 - rho_[n]) * var_x0[n] * var_n0[n];
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if (quadratic) {
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alpha0 = lambda * var_x0[n] * (1 - rho_[n]) * var_x0[n] * var_x0[n];
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sols[n] = (-beta0 - sqrtf(beta0 * beta0 - 4 * alpha0 * gamma0))
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/ (2 * alpha0);
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} else {
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sols[n] = -gamma0 / beta0;
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}
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sols[n] = fmax(0, sols[n]);
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}
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}
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void IntelligibilityEnhancer::FilterVariance(const float* var, float* result) {
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for (int i = 0; i < bank_size_; ++i) {
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result[i] = DotProduct(filter_bank_[i], var, freqs_);
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}
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}
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float IntelligibilityEnhancer::DotProduct(const float* a, const float* b,
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int length) {
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float ret = 0.0f;
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for (int i = 0; i < length; ++i) {
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ret = fmaf(a[i], b[i], ret);
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}
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return ret;
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}
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} // namespace webrtc
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@@ -0,0 +1,137 @@
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/*
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* Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#ifndef WEBRTC_MODULES_AUDIO_PROCESSING_INTELLIGIBILITY_INTELLIGIBILITY_ENHANCER_H_
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#define WEBRTC_MODULES_AUDIO_PROCESSING_INTELLIGIBILITY_INTELLIGIBILITY_ENHANCER_H_
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#include <complex>
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#include "webrtc/common_audio/lapped_transform.h"
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#include "webrtc/modules/audio_processing/intelligibility/intelligibility_utils.h"
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#include "webrtc/system_wrappers/interface/scoped_ptr.h"
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struct WebRtcVadInst;
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typedef struct WebRtcVadInst VadInst;
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namespace webrtc {
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// Speech intelligibility enhancement module. Reads render and capture
|
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// audio streams and modifies the render stream with a set of gains per
|
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// frequency bin to enhance speech against the noise background.
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class IntelligibilityEnhancer {
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public:
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// Construct a new instance with the given filter bank resolution,
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// sampling rate, number of channels and analysis rates.
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// |analysis_rate| sets the number of input blocks (containing speech!)
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// to elapse before a new gain computation is made. |variance_rate| specifies
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// the number of gain recomputations after which the variances are reset.
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// |cv_*| are parameters for the VarianceArray constructor for the
|
||||
// lear speech stream.
|
||||
// TODO(bercic): the |cv_*|, |*_rate| and |gain_limit| parameters should
|
||||
// probably go away once fine tuning is done. They override the internal
|
||||
// constants in the class (kGainChangeLimit, kAnalyzeRate, kVarianceRate).
|
||||
IntelligibilityEnhancer(int erb_resolution, int sample_rate_hz, int channels,
|
||||
int cv_type, float cv_alpha, int cv_win,
|
||||
int analysis_rate, int variance_rate,
|
||||
float gain_limit);
|
||||
~IntelligibilityEnhancer();
|
||||
|
||||
void ProcessRenderAudio(float* const* audio);
|
||||
void ProcessCaptureAudio(float* const* audio);
|
||||
|
||||
private:
|
||||
enum AudioSource {
|
||||
kRenderStream = 0,
|
||||
kCaptureStream,
|
||||
};
|
||||
|
||||
class TransformCallback : public LappedTransform::Callback {
|
||||
public:
|
||||
TransformCallback(IntelligibilityEnhancer* parent, AudioSource source);
|
||||
virtual void ProcessAudioBlock(const std::complex<float>* const* in_block,
|
||||
int in_channels, int frames,
|
||||
int out_channels,
|
||||
std::complex<float>* const* out_block);
|
||||
|
||||
private:
|
||||
IntelligibilityEnhancer* parent_;
|
||||
AudioSource source_;
|
||||
};
|
||||
friend class TransformCallback;
|
||||
|
||||
void DispatchAudio(AudioSource source, const std::complex<float>* in_block,
|
||||
std::complex<float>* out_block);
|
||||
void ProcessClearBlock(const std::complex<float>* in_block,
|
||||
std::complex<float>* out_block);
|
||||
void AnalyzeClearBlock(float power_target);
|
||||
void ProcessNoiseBlock(const std::complex<float>* in_block,
|
||||
std::complex<float>* out_block);
|
||||
|
||||
static int GetBankSize(int sample_rate, int erb_resolution);
|
||||
void CreateErbBank();
|
||||
void SolveEquation14(float lambda, int start_freq, float* sols);
|
||||
void FilterVariance(const float* var, float* result);
|
||||
static float DotProduct(const float* a, const float* b, int length);
|
||||
|
||||
static const int kErbResolution;
|
||||
static const int kWindowSizeMs;
|
||||
static const int kChunkSizeMs;
|
||||
static const int kAnalyzeRate;
|
||||
static const int kVarianceRate;
|
||||
static const float kClipFreq;
|
||||
static const float kConfigRho;
|
||||
static const float kKbdAlpha;
|
||||
static const float kGainChangeLimit;
|
||||
|
||||
const int freqs_;
|
||||
const int window_size_; // window size in samples; also the block size
|
||||
const int chunk_length_; // chunk size in samples
|
||||
const int bank_size_;
|
||||
const int sample_rate_hz_;
|
||||
const int erb_resolution_;
|
||||
const int channels_;
|
||||
const int analysis_rate_;
|
||||
const int variance_rate_;
|
||||
|
||||
intelligibility::VarianceArray clear_variance_;
|
||||
intelligibility::VarianceArray noise_variance_;
|
||||
scoped_ptr<float[]> filtered_clear_var_;
|
||||
scoped_ptr<float[]> filtered_noise_var_;
|
||||
float** filter_bank_;
|
||||
scoped_ptr<float[]> center_freqs_;
|
||||
int start_freq_;
|
||||
scoped_ptr<float[]> rho_;
|
||||
scoped_ptr<float[]> gains_eq_;
|
||||
intelligibility::GainApplier gain_applier_;
|
||||
|
||||
// Destination buffer used to reassemble blocked chunks before overwriting
|
||||
// the original input array with modifications.
|
||||
float** temp_out_buffer_;
|
||||
scoped_ptr<float*[]> input_audio_;
|
||||
scoped_ptr<float[]> kbd_window_;
|
||||
TransformCallback render_callback_;
|
||||
TransformCallback capture_callback_;
|
||||
scoped_ptr<LappedTransform> render_mangler_;
|
||||
scoped_ptr<LappedTransform> capture_mangler_;
|
||||
int block_count_;
|
||||
int analysis_step_;
|
||||
|
||||
// TODO(bercic): Quick stopgap measure for voice detection in the clear
|
||||
// and noise streams.
|
||||
VadInst* vad_high_;
|
||||
VadInst* vad_low_;
|
||||
scoped_ptr<int16_t[]> vad_tmp_buffer_;
|
||||
bool has_voice_low_;
|
||||
};
|
||||
|
||||
} // namespace webrtc
|
||||
|
||||
#endif // WEBRTC_MODULES_AUDIO_PROCESSING_INTELLIGIBILITY_INTELLIGIBILITY_ENHANCER_H_
|
||||
|
||||
@@ -0,0 +1,187 @@
|
||||
/*
|
||||
* Copyright (c) 2014 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 <arpa/inet.h>
|
||||
#include <fcntl.h>
|
||||
#include <stdint.h>
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <sys/mman.h>
|
||||
#include <sys/stat.h>
|
||||
#include <sys/types.h>
|
||||
#include <unistd.h>
|
||||
|
||||
#include <fenv.h>
|
||||
#include <limits>
|
||||
|
||||
#include <complex>
|
||||
|
||||
#include "gflags/gflags.h"
|
||||
#include "webrtc/base/checks.h"
|
||||
#include "webrtc/common_audio/real_fourier.h"
|
||||
#include "webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.h"
|
||||
#include "webrtc/modules/audio_processing/intelligibility/intelligibility_utils.h"
|
||||
#include "webrtc/system_wrappers/interface/critical_section_wrapper.h"
|
||||
#include "webrtc/system_wrappers/interface/scoped_ptr.h"
|
||||
|
||||
const int16_t* in_ipcm;
|
||||
int16_t* out_ipcm;
|
||||
const int16_t* noise_ipcm;
|
||||
|
||||
float* in_fpcm;
|
||||
float* out_fpcm;
|
||||
float* noise_fpcm;
|
||||
float* noise_cursor;
|
||||
float* clear_cursor;
|
||||
|
||||
int samples;
|
||||
int fragment_size;
|
||||
|
||||
using std::complex;
|
||||
using webrtc::RealFourier;
|
||||
using webrtc::IntelligibilityEnhancer;
|
||||
|
||||
DEFINE_int32(clear_type, webrtc::intelligibility::VarianceArray::kStepInfinite,
|
||||
"Variance algorithm for clear data.");
|
||||
DEFINE_double(clear_alpha, 0.9,
|
||||
"Variance decay factor for clear data.");
|
||||
DEFINE_int32(clear_window, 475,
|
||||
"Window size for windowed variance for clear data.");
|
||||
DEFINE_int32(sample_rate, 16000,
|
||||
"Audio sample rate used in the input and output files.");
|
||||
DEFINE_int32(ana_rate, 800,
|
||||
"Analysis rate; gains recalculated every N blocks.");
|
||||
DEFINE_int32(var_rate, 2,
|
||||
"Variance clear rate; history is forgotten every N gain recalculations.");
|
||||
DEFINE_double(gain_limit, 1000.0, "Maximum gain change in one block.");
|
||||
|
||||
DEFINE_bool(repeat, false, "Repeat input file ad nauseam.");
|
||||
|
||||
DEFINE_string(clear_file, "speech.pcm", "Input file with clear speech.");
|
||||
DEFINE_string(noise_file, "noise.pcm", "Input file with noise data.");
|
||||
DEFINE_string(out_file, "proc_enhanced.pcm", "Enhanced output. Use '-' to "
|
||||
"pipe through aplay internally.");
|
||||
|
||||
// Write an Sun AU-formatted audio chunk into file descriptor |fd|. Can be used
|
||||
// to pipe the audio stream directly into aplay.
|
||||
void writeau(int fd) {
|
||||
uint32_t thing;
|
||||
|
||||
write(fd, ".snd", 4);
|
||||
thing = htonl(24);
|
||||
write(fd, &thing, sizeof(thing));
|
||||
thing = htonl(0xffffffff);
|
||||
write(fd, &thing, sizeof(thing));
|
||||
thing = htonl(3);
|
||||
write(fd, &thing, sizeof(thing));
|
||||
thing = htonl(FLAGS_sample_rate);
|
||||
write(fd, &thing, sizeof(thing));
|
||||
thing = htonl(1);
|
||||
write(fd, &thing, sizeof(thing));
|
||||
|
||||
for (int i = 0; i < samples; ++i) {
|
||||
out_ipcm[i] = htons(out_ipcm[i]);
|
||||
}
|
||||
write(fd, out_ipcm, sizeof(*out_ipcm) * samples);
|
||||
}
|
||||
|
||||
int main(int argc, char* argv[]) {
|
||||
google::SetUsageMessage("\n\nVariance algorithm types are:\n"
|
||||
" 0 - infinite/normal,\n"
|
||||
" 1 - exponentially decaying,\n"
|
||||
" 2 - rolling window.\n"
|
||||
"\nInput files must be little-endian 16-bit signed raw PCM.\n");
|
||||
google::ParseCommandLineFlags(&argc, &argv, true);
|
||||
|
||||
const char* in_name = FLAGS_clear_file.c_str();
|
||||
const char* out_name = FLAGS_out_file.c_str();
|
||||
const char* noise_name = FLAGS_noise_file.c_str();
|
||||
struct stat in_stat, noise_stat;
|
||||
int in_fd, out_fd, noise_fd;
|
||||
FILE* aplay_file = nullptr;
|
||||
|
||||
fragment_size = FLAGS_sample_rate / 100;
|
||||
|
||||
stat(in_name, &in_stat);
|
||||
stat(noise_name, &noise_stat);
|
||||
samples = in_stat.st_size / sizeof(*in_ipcm);
|
||||
|
||||
in_fd = open(in_name, O_RDONLY);
|
||||
if (!strcmp(out_name, "-")) {
|
||||
aplay_file = popen("aplay -t au", "w");
|
||||
out_fd = fileno(aplay_file);
|
||||
} else {
|
||||
out_fd = open(out_name, O_WRONLY | O_CREAT | O_TRUNC,
|
||||
S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
|
||||
}
|
||||
noise_fd = open(noise_name, O_RDONLY);
|
||||
|
||||
in_ipcm = static_cast<int16_t*>(mmap(nullptr, in_stat.st_size, PROT_READ,
|
||||
MAP_PRIVATE, in_fd, 0));
|
||||
noise_ipcm = static_cast<int16_t*>(mmap(nullptr, noise_stat.st_size,
|
||||
PROT_READ, MAP_PRIVATE, noise_fd, 0));
|
||||
out_ipcm = new int16_t[samples];
|
||||
out_fpcm = new float[samples];
|
||||
in_fpcm = new float[samples];
|
||||
noise_fpcm = new float[samples];
|
||||
|
||||
for (int i = 0; i < samples; ++i) {
|
||||
noise_fpcm[i] = noise_ipcm[i % (noise_stat.st_size / sizeof(*noise_ipcm))];
|
||||
}
|
||||
|
||||
//feenableexcept(FE_INVALID | FE_OVERFLOW);
|
||||
IntelligibilityEnhancer enh(2,
|
||||
FLAGS_sample_rate, 1,
|
||||
FLAGS_clear_type,
|
||||
static_cast<float>(FLAGS_clear_alpha),
|
||||
FLAGS_clear_window,
|
||||
FLAGS_ana_rate,
|
||||
FLAGS_var_rate,
|
||||
FLAGS_gain_limit);
|
||||
|
||||
// Slice the input into smaller chunks, as the APM would do, and feed them
|
||||
// into the enhancer. Repeat indefinitely if FLAGS_repeat is set.
|
||||
do {
|
||||
noise_cursor = noise_fpcm;
|
||||
clear_cursor = in_fpcm;
|
||||
for (int i = 0; i < samples; ++i) {
|
||||
in_fpcm[i] = in_ipcm[i];
|
||||
}
|
||||
|
||||
for (int i = 0; i < samples; i += fragment_size) {
|
||||
enh.ProcessCaptureAudio(&noise_cursor);
|
||||
enh.ProcessRenderAudio(&clear_cursor);
|
||||
clear_cursor += fragment_size;
|
||||
noise_cursor += fragment_size;
|
||||
}
|
||||
|
||||
for (int i = 0; i < samples; ++i) {
|
||||
out_ipcm[i] = static_cast<float>(in_fpcm[i]);
|
||||
}
|
||||
if (!strcmp(out_name, "-")) {
|
||||
writeau(out_fd);
|
||||
} else {
|
||||
write(out_fd, out_ipcm, samples * sizeof(*out_ipcm));
|
||||
}
|
||||
} while (FLAGS_repeat);
|
||||
|
||||
munmap(const_cast<int16_t*>(noise_ipcm), noise_stat.st_size);
|
||||
munmap(const_cast<int16_t*>(in_ipcm), in_stat.st_size);
|
||||
close(noise_fd);
|
||||
if (aplay_file) {
|
||||
pclose(aplay_file);
|
||||
} else {
|
||||
close(out_fd);
|
||||
}
|
||||
close(in_fd);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@@ -0,0 +1,287 @@
|
||||
/*
|
||||
* Copyright (c) 2014 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 "webrtc/modules/audio_processing/intelligibility/intelligibility_utils.h"
|
||||
|
||||
#include <algorithm>
|
||||
#include <cmath>
|
||||
#include <cstring>
|
||||
|
||||
using std::complex;
|
||||
|
||||
namespace {
|
||||
|
||||
// Return |current| changed towards |target|, with the change being at most
|
||||
// |limit|.
|
||||
inline float UpdateFactor(float target, float current, float limit) {
|
||||
float delta = fabsf(target - current);
|
||||
float sign = copysign(1.0f, target - current);
|
||||
return current + sign * fminf(delta, limit);
|
||||
}
|
||||
|
||||
// std::isfinite for complex numbers.
|
||||
inline bool cplxfinite(complex<float> c) {
|
||||
return std::isfinite(c.real()) && std::isfinite(c.imag());
|
||||
}
|
||||
|
||||
// std::isnormal for complex numbers.
|
||||
inline bool cplxnormal(complex<float> c) {
|
||||
return std::isnormal(c.real()) && std::isnormal(c.imag());
|
||||
}
|
||||
|
||||
// Apply a small fudge to degenerate complex values. The numbers in the array
|
||||
// were chosen randomly, so that even a series of all zeroes has some small
|
||||
// variability.
|
||||
inline complex<float> zerofudge(complex<float> c) {
|
||||
const static complex<float> fudge[7] = {
|
||||
{0.001f, 0.002f}, {0.008f, 0.001f}, {0.003f, 0.008f}, {0.0006f, 0.0009f},
|
||||
{0.001f, 0.004f}, {0.003f, 0.004f}, {0.002f, 0.009f}
|
||||
};
|
||||
static int fudge_index = 0;
|
||||
if (cplxfinite(c) && !cplxnormal(c)) {
|
||||
fudge_index = (fudge_index + 1) % 7;
|
||||
return c + fudge[fudge_index];
|
||||
}
|
||||
return c;
|
||||
}
|
||||
|
||||
// Incremental mean computation. Return the mean of the series with the
|
||||
// mean |mean| with added |data|.
|
||||
inline complex<float> NewMean(complex<float> mean, complex<float> data,
|
||||
int count) {
|
||||
return mean + (data - mean) / static_cast<float>(count);
|
||||
}
|
||||
|
||||
inline void AddToMean(complex<float> data, int count, complex<float>* mean) {
|
||||
(*mean) = NewMean(*mean, data, count);
|
||||
}
|
||||
|
||||
} // namespace
|
||||
|
||||
using std::min;
|
||||
|
||||
namespace webrtc {
|
||||
|
||||
namespace intelligibility {
|
||||
|
||||
static const int kWindowBlockSize = 10;
|
||||
|
||||
VarianceArray::VarianceArray(int freqs, StepType type, int window_size,
|
||||
float decay)
|
||||
: running_mean_(new complex<float>[freqs]()),
|
||||
running_mean_sq_(new complex<float>[freqs]()),
|
||||
sub_running_mean_(new complex<float>[freqs]()),
|
||||
sub_running_mean_sq_(new complex<float>[freqs]()),
|
||||
variance_(new float[freqs]()),
|
||||
conj_sum_(new float[freqs]()),
|
||||
freqs_(freqs),
|
||||
window_size_(window_size),
|
||||
decay_(decay),
|
||||
history_cursor_(0),
|
||||
count_(0),
|
||||
array_mean_(0.0f) {
|
||||
history_.reset(new scoped_ptr<complex<float>[]>[freqs_]());
|
||||
for (int i = 0; i < freqs_; ++i) {
|
||||
history_[i].reset(new complex<float>[window_size_]());
|
||||
}
|
||||
subhistory_.reset(new scoped_ptr<complex<float>[]>[freqs_]());
|
||||
for (int i = 0; i < freqs_; ++i) {
|
||||
subhistory_[i].reset(new complex<float>[window_size_]());
|
||||
}
|
||||
subhistory_sq_.reset(new scoped_ptr<complex<float>[]>[freqs_]());
|
||||
for (int i = 0; i < freqs_; ++i) {
|
||||
subhistory_sq_[i].reset(new complex<float>[window_size_]());
|
||||
}
|
||||
switch (type) {
|
||||
case kStepInfinite:
|
||||
step_func_ = &VarianceArray::InfiniteStep;
|
||||
break;
|
||||
case kStepDecaying:
|
||||
step_func_ = &VarianceArray::DecayStep;
|
||||
break;
|
||||
case kStepWindowed:
|
||||
step_func_ = &VarianceArray::WindowedStep;
|
||||
break;
|
||||
case kStepBlocked:
|
||||
step_func_ = &VarianceArray::BlockedStep;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
// Compute the variance with Welford's algorithm, adding some fudge to
|
||||
// the input in case of all-zeroes.
|
||||
void VarianceArray::InfiniteStep(const complex<float>* data, bool skip_fudge) {
|
||||
array_mean_ = 0.0f;
|
||||
++count_;
|
||||
for (int i = 0; i < freqs_; ++i) {
|
||||
complex<float> sample = data[i];
|
||||
if (!skip_fudge) {
|
||||
sample = zerofudge(sample);
|
||||
}
|
||||
if (count_ == 1) {
|
||||
running_mean_[i] = sample;
|
||||
variance_[i] = 0.0f;
|
||||
} else {
|
||||
float old_sum = conj_sum_[i];
|
||||
complex<float> old_mean = running_mean_[i];
|
||||
running_mean_[i] = old_mean + (sample - old_mean) /
|
||||
static_cast<float>(count_);
|
||||
conj_sum_[i] = (old_sum + std::conj(sample - old_mean) *
|
||||
(sample - running_mean_[i])).real();
|
||||
variance_[i] = conj_sum_[i] / (count_ - 1); // + fudge[fudge_index].real();
|
||||
if (skip_fudge && false) {
|
||||
//variance_[i] -= fudge[fudge_index].real();
|
||||
}
|
||||
}
|
||||
array_mean_ += (variance_[i] - array_mean_) / (i + 1);
|
||||
}
|
||||
}
|
||||
|
||||
// Compute the variance from the beginning, with exponential decaying of the
|
||||
// series data.
|
||||
void VarianceArray::DecayStep(const complex<float>* data, bool /*dummy*/) {
|
||||
array_mean_ = 0.0f;
|
||||
++count_;
|
||||
for (int i = 0; i < freqs_; ++i) {
|
||||
complex<float> sample = data[i];
|
||||
sample = zerofudge(sample);
|
||||
|
||||
if (count_ == 1) {
|
||||
running_mean_[i] = sample;
|
||||
running_mean_sq_[i] = sample * std::conj(sample);
|
||||
variance_[i] = 0.0f;
|
||||
} else {
|
||||
complex<float> prev = running_mean_[i];
|
||||
complex<float> prev2 = running_mean_sq_[i];
|
||||
running_mean_[i] = decay_ * prev + (1.0f - decay_) * sample;
|
||||
running_mean_sq_[i] = decay_ * prev2 +
|
||||
(1.0f - decay_) * sample * std::conj(sample);
|
||||
//variance_[i] = decay_ * variance_[i] + (1.0f - decay_) * (
|
||||
// (sample - running_mean_[i]) * std::conj(sample - running_mean_[i])).real();
|
||||
variance_[i] = (running_mean_sq_[i] - running_mean_[i] * std::conj(running_mean_[i])).real();
|
||||
}
|
||||
|
||||
array_mean_ += (variance_[i] - array_mean_) / (i + 1);
|
||||
}
|
||||
}
|
||||
|
||||
// Windowed variance computation. On each step, the variances for the
|
||||
// window are recomputed from scratch, using Welford's algorithm.
|
||||
void VarianceArray::WindowedStep(const complex<float>* data, bool /*dummy*/) {
|
||||
int num = min(count_ + 1, window_size_);
|
||||
array_mean_ = 0.0f;
|
||||
for (int i = 0; i < freqs_; ++i) {
|
||||
complex<float> mean;
|
||||
float conj_sum = 0.0f;
|
||||
|
||||
history_[i][history_cursor_] = data[i];
|
||||
|
||||
mean = history_[i][history_cursor_];
|
||||
variance_[i] = 0.0f;
|
||||
for (int j = 1; j < num; ++j) {
|
||||
complex<float> sample = zerofudge(
|
||||
history_[i][(history_cursor_ + j) % window_size_]);
|
||||
sample = history_[i][(history_cursor_ + j) % window_size_];
|
||||
float old_sum = conj_sum;
|
||||
complex<float> old_mean = mean;
|
||||
|
||||
mean = old_mean + (sample - old_mean) / static_cast<float>(j + 1);
|
||||
conj_sum = (old_sum + std::conj(sample - old_mean) *
|
||||
(sample - mean)).real();
|
||||
variance_[i] = conj_sum / (j);
|
||||
}
|
||||
array_mean_ += (variance_[i] - array_mean_) / (i + 1);
|
||||
}
|
||||
history_cursor_ = (history_cursor_ + 1) % window_size_;
|
||||
++count_;
|
||||
}
|
||||
|
||||
// Variance with a window of blocks. Within each block, the variances are
|
||||
// recomputed from scratch at every stp, using |Var(X) = E(X^2) - E^2(X)|.
|
||||
// Once a block is filled with kWindowBlockSize samples, it is added to the
|
||||
// history window and a new block is started. The variances for the window
|
||||
// are recomputed from scratch at each of these transitions.
|
||||
void VarianceArray::BlockedStep(const complex<float>* data, bool /*dummy*/) {
|
||||
int blocks = min(window_size_, history_cursor_);
|
||||
for (int i = 0; i < freqs_; ++i) {
|
||||
AddToMean(data[i], count_ + 1, &sub_running_mean_[i]);
|
||||
AddToMean(data[i] * std::conj(data[i]), count_ + 1,
|
||||
&sub_running_mean_sq_[i]);
|
||||
subhistory_[i][history_cursor_ % window_size_] = sub_running_mean_[i];
|
||||
subhistory_sq_[i][history_cursor_ % window_size_] = sub_running_mean_sq_[i];
|
||||
|
||||
variance_[i] = (NewMean(running_mean_sq_[i], sub_running_mean_sq_[i],
|
||||
blocks) -
|
||||
NewMean(running_mean_[i], sub_running_mean_[i], blocks) *
|
||||
std::conj(NewMean(running_mean_[i], sub_running_mean_[i],
|
||||
blocks))).real();
|
||||
if (count_ == kWindowBlockSize - 1) {
|
||||
sub_running_mean_[i] = complex<float>(0.0f, 0.0f);
|
||||
sub_running_mean_sq_[i] = complex<float>(0.0f, 0.0f);
|
||||
running_mean_[i] = complex<float>(0.0f, 0.0f);
|
||||
running_mean_sq_[i] = complex<float>(0.0f, 0.0f);
|
||||
for (int j = 0; j < min(window_size_, history_cursor_); ++j) {
|
||||
AddToMean(subhistory_[i][j], j, &running_mean_[i]);
|
||||
AddToMean(subhistory_sq_[i][j], j, &running_mean_sq_[i]);
|
||||
}
|
||||
++history_cursor_;
|
||||
}
|
||||
}
|
||||
++count_;
|
||||
if (count_ == kWindowBlockSize) {
|
||||
count_ = 0;
|
||||
}
|
||||
}
|
||||
|
||||
void VarianceArray::Clear() {
|
||||
memset(running_mean_.get(), 0, sizeof(*running_mean_.get()) * freqs_);
|
||||
memset(running_mean_sq_.get(), 0, sizeof(*running_mean_sq_.get()) * freqs_);
|
||||
memset(variance_.get(), 0, sizeof(*variance_.get()) * freqs_);
|
||||
memset(conj_sum_.get(), 0, sizeof(*conj_sum_.get()) * freqs_);
|
||||
history_cursor_ = 0;
|
||||
count_ = 0;
|
||||
array_mean_ = 0.0f;
|
||||
}
|
||||
|
||||
void VarianceArray::ApplyScale(float scale) {
|
||||
array_mean_ = 0.0f;
|
||||
for (int i = 0; i < freqs_; ++i) {
|
||||
variance_[i] *= scale * scale;
|
||||
array_mean_ += (variance_[i] - array_mean_) / (i + 1);
|
||||
}
|
||||
}
|
||||
|
||||
GainApplier::GainApplier(int freqs, float change_limit)
|
||||
: freqs_(freqs),
|
||||
change_limit_(change_limit),
|
||||
target_(new float[freqs]()),
|
||||
current_(new float[freqs]()) {
|
||||
for (int i = 0; i < freqs; ++i) {
|
||||
target_[i] = 1.0f;
|
||||
current_[i] = 1.0f;
|
||||
}
|
||||
}
|
||||
|
||||
void GainApplier::Apply(const complex<float>* in_block,
|
||||
complex<float>* out_block) {
|
||||
for (int i = 0; i < freqs_; ++i) {
|
||||
float factor = sqrtf(fabsf(current_[i]));
|
||||
if (!std::isnormal(factor)) {
|
||||
factor = 1.0f;
|
||||
}
|
||||
out_block[i] = factor * in_block[i];
|
||||
current_[i] = UpdateFactor(target_[i], current_[i], change_limit_);
|
||||
}
|
||||
}
|
||||
|
||||
} // namespace intelligibility
|
||||
|
||||
} // namespace webrtc
|
||||
|
||||
@@ -0,0 +1,137 @@
|
||||
/*
|
||||
* Copyright (c) 2014 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.
|
||||
*/
|
||||
|
||||
#ifndef WEBRTC_MODULES_AUDIO_PROCESSING_INTELLIGIBILITY_INTELLIGIBILITY_UTILS_H_
|
||||
#define WEBRTC_MODULES_AUDIO_PROCESSING_INTELLIGIBILITY_INTELLIGIBILITY_UTILS_H_
|
||||
|
||||
#include <complex>
|
||||
|
||||
#include "webrtc/system_wrappers/interface/scoped_ptr.h"
|
||||
|
||||
namespace webrtc {
|
||||
|
||||
namespace intelligibility {
|
||||
|
||||
// Internal helper for computing the variances of a stream of arrays.
|
||||
// The result is an array of variances per position: the i-th variance
|
||||
// is the variance of the stream of data on the i-th positions in the
|
||||
// input arrays.
|
||||
// There are four methods of computation:
|
||||
// * kStepInfinite computes variances from the beginning onwards
|
||||
// * kStepDecaying uses a recursive exponential decay formula with a
|
||||
// settable forgetting factor
|
||||
// * kStepWindowed computes variances within a moving window
|
||||
// * kStepBlocked is similar to kStepWindowed, but history is kept
|
||||
// as a rolling window of blocks: multiple input elements are used for
|
||||
// one block and the history then consists of the variances of these blocks
|
||||
// with the same effect as kStepWindowed, but less storage, so the window
|
||||
// can be longer
|
||||
class VarianceArray {
|
||||
public:
|
||||
enum StepType {
|
||||
kStepInfinite = 0,
|
||||
kStepDecaying,
|
||||
kStepWindowed,
|
||||
kStepBlocked
|
||||
};
|
||||
|
||||
// Construct an instance for the given input array length (|freqs|) and
|
||||
// computation algorithm (|type|), with the appropriate parameters.
|
||||
// |window_size| is the number of samples for kStepWindowed and
|
||||
// the number of blocks for kStepBlocked. |decay| is the forgetting factor
|
||||
// for kStepDecaying.
|
||||
VarianceArray(int freqs, StepType type, int window_size, float decay);
|
||||
|
||||
// Add a new data point to the series and compute the new variances.
|
||||
// TODO(bercic) |skip_fudge| is a flag for kStepWindowed and kStepDecaying,
|
||||
// whether they should skip adding some small dummy values to the input
|
||||
// to prevent problems with all-zero inputs. Can probably be removed.
|
||||
void Step(const std::complex<float>* data, bool skip_fudge = false) {
|
||||
(this->*step_func_)(data, skip_fudge);
|
||||
}
|
||||
// Reset variances to zero and forget all history.
|
||||
void Clear();
|
||||
// Scale the input data by |scale|. Effectively multiply variances
|
||||
// by |scale^2|.
|
||||
void ApplyScale(float scale);
|
||||
|
||||
// The current set of variances.
|
||||
const float* variance() const {
|
||||
return variance_.get();
|
||||
}
|
||||
|
||||
// The mean value of the current set of variances.
|
||||
float array_mean() const {
|
||||
return array_mean_;
|
||||
}
|
||||
|
||||
private:
|
||||
void InfiniteStep(const std::complex<float>* data, bool dummy);
|
||||
void DecayStep(const std::complex<float>* data, bool dummy);
|
||||
void WindowedStep(const std::complex<float>* data, bool dummy);
|
||||
void BlockedStep(const std::complex<float>* data, bool dummy);
|
||||
|
||||
// The current average X and X^2.
|
||||
scoped_ptr<std::complex<float>[]> running_mean_;
|
||||
scoped_ptr<std::complex<float>[]> running_mean_sq_;
|
||||
|
||||
// Average X and X^2 for the current block in kStepBlocked.
|
||||
scoped_ptr<std::complex<float>[]> sub_running_mean_;
|
||||
scoped_ptr<std::complex<float>[]> sub_running_mean_sq_;
|
||||
|
||||
// Sample history for the rolling window in kStepWindowed and block-wise
|
||||
// histories for kStepBlocked.
|
||||
scoped_ptr<scoped_ptr<std::complex<float>[]>[]> history_;
|
||||
scoped_ptr<scoped_ptr<std::complex<float>[]>[]> subhistory_;
|
||||
scoped_ptr<scoped_ptr<std::complex<float>[]>[]> subhistory_sq_;
|
||||
|
||||
// The current set of variances and sums for Welford's algorithm.
|
||||
scoped_ptr<float[]> variance_;
|
||||
scoped_ptr<float[]> conj_sum_;
|
||||
|
||||
const int freqs_;
|
||||
const int window_size_;
|
||||
const float decay_;
|
||||
int history_cursor_;
|
||||
int count_;
|
||||
float array_mean_;
|
||||
void (VarianceArray::*step_func_)(const std::complex<float>*, bool);
|
||||
};
|
||||
|
||||
// Helper class for smoothing gain changes. On each applicatiion step, the
|
||||
// currently used gains are changed towards a set of settable target gains,
|
||||
// constrained by a limit on the magnitude of the changes.
|
||||
class GainApplier {
|
||||
public:
|
||||
GainApplier(int freqs, float change_limit);
|
||||
|
||||
// Copy |in_block| to |out_block|, multiplied by the current set of gains,
|
||||
// and step the current set of gains towards the target set.
|
||||
void Apply(const std::complex<float>* in_block,
|
||||
std::complex<float>* out_block);
|
||||
|
||||
// Return the current target gain set. Modify this array to set the targets.
|
||||
float* target() const {
|
||||
return target_.get();
|
||||
}
|
||||
|
||||
private:
|
||||
const int freqs_;
|
||||
const float change_limit_;
|
||||
scoped_ptr<float[]> target_;
|
||||
scoped_ptr<float[]> current_;
|
||||
};
|
||||
|
||||
} // namespace intelligibility
|
||||
|
||||
} // namespace webrtc
|
||||
|
||||
#endif // WEBRTC_MODULES_AUDIO_PROCESSING_INTELLIGIBILITY_INTELLIGIBILITY_UTILS_H_
|
||||
|
||||
Reference in New Issue
Block a user