Files
platform-external-webrtc/modules/audio_processing/agc2/adaptive_agc.cc
Alex Loiko 2bac896d5e Adaptive Digital gain control structure.
This CL defines the control flow of the adaptive AGC. It also defines
method and class stubs.

Contents:
1. Divide the 'agc2' build target into 'fixed_digital' and
'adaptive_digital'.
1. Update the dependencies of everything that depended on 'agc2'.
2. Define the sub-modules of the adaptive digital AGC 2. They are:
   1. Level Estimator - it gets the energy and a speech probability
      and updates a speech level estimate.
   2. Noise Estimator - it gets an immutable view of the speech frame
      and updates the noise level estimate
   3. Gain applier - it gets the speech frame, the current speech and
      noise estimates, and the speech probability. It finds a gain to
      apply and applies it.
   4. AdaptiveAgc - sets up and controls the sub-modules described
      above.

Bug: webrtc:7494
Change-Id: Ib7ccd8924e94eead0bc5f935b5d8a12e06e24fd1
Reviewed-on: https://webrtc-review.googlesource.com/64440
Reviewed-by: Alessio Bazzica <alessiob@webrtc.org>
Commit-Queue: Alex Loiko <aleloi@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22628}
2018-03-27 14:12:50 +00:00

60 lines
2.1 KiB
C++

/*
* Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "modules/audio_processing/agc2/adaptive_agc.h"
#include <algorithm>
#include <numeric>
#include "common_audio/include/audio_util.h"
#include "modules/audio_processing/logging/apm_data_dumper.h"
#include "modules/audio_processing/vad/voice_activity_detector.h"
namespace webrtc {
AdaptiveAgc::AdaptiveAgc(ApmDataDumper* apm_data_dumper)
: speech_level_estimator_(apm_data_dumper),
gain_applier_(apm_data_dumper),
apm_data_dumper_(apm_data_dumper) {
RTC_DCHECK(apm_data_dumper);
}
AdaptiveAgc::~AdaptiveAgc() = default;
void AdaptiveAgc::Process(AudioFrameView<float> float_frame) {
// Some VADs are 'bursty'. They return several estimates for some
// frames, and no estimates for other frames. We want to feed all to
// the level estimator, but only care about the last level it
// produces.
rtc::ArrayView<const VadWithLevel::LevelAndProbability> vad_results =
vad_.AnalyzeFrame(float_frame);
for (const auto& vad_result : vad_results) {
apm_data_dumper_->DumpRaw("agc2_vad_probability",
vad_result.speech_probability);
apm_data_dumper_->DumpRaw("agc2_vad_rms_dbfs", vad_result.speech_rms_dbfs);
apm_data_dumper_->DumpRaw("agc2_vad_peak_dbfs",
vad_result.speech_peak_dbfs);
speech_level_estimator_.UpdateEstimation(vad_result);
}
const float speech_level_dbfs = speech_level_estimator_.LatestLevelEstimate();
const float noise_level_dbfs = noise_level_estimator_.Analyze(float_frame);
apm_data_dumper_->DumpRaw("agc2_noise_estimate_dbfs", noise_level_dbfs);
// The gain applier applies the gain.
gain_applier_.Process(speech_level_dbfs, noise_level_dbfs, vad_results,
float_frame);
}
} // namespace webrtc