Added functionality for specifying the initial signal level to use for the gain estimation in the l…

webrtc/modules/audio_processing/level_controller/level_controller.cc

 /*
  *  Copyright (c) 2016 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.
  */
 
@@ skipping 137 matching lines @@
 LevelController::LevelController()
     : data_dumper_(new ApmDataDumper(instance_count_)),
       gain_applier_(data_dumper_.get()),
       signal_classifier_(data_dumper_.get()) {
   Initialize(AudioProcessing::kSampleRate48kHz);
   ++instance_count_;
 }
 
 LevelController::~LevelController() {}
 
+void LevelController::SetInitialLevel(float level) {
+  peak_level_estimator_.SetInitialLevel(level);
+  gain_jumpstart_ = true;
+}
+
 void LevelController::Initialize(int sample_rate_hz) {
   RTC_DCHECK(sample_rate_hz == AudioProcessing::kSampleRate8kHz ||
              sample_rate_hz == AudioProcessing::kSampleRate16kHz ||
              sample_rate_hz == AudioProcessing::kSampleRate32kHz ||
              sample_rate_hz == AudioProcessing::kSampleRate48kHz);
   data_dumper_->InitiateNewSetOfRecordings();
   gain_selector_.Initialize(sample_rate_hz);
   gain_applier_.Initialize(sample_rate_hz);
   signal_classifier_.Initialize(sample_rate_hz);
   noise_level_estimator_.Initialize(sample_rate_hz);
@@ skipping 31 matching lines @@
   float noise_energy =
       noise_level_estimator_.Analyze(signal_type, FrameEnergy(*audio));
 
   // Estimate the overall signal peak level.
   float peak_level =
       peak_level_estimator_.Analyze(signal_type, PeakLevel(*audio));
 
   float saturating_gain = saturating_gain_estimator_.GetGain();
 
   // Compute the new gain to apply.
-  last_gain_ = gain_selector_.GetNewGain(peak_level, noise_energy,
-                                         saturating_gain, signal_type);
+  last_gain_ = gain_selector_.GetNewGain(
+      peak_level, noise_energy, saturating_gain, gain_jumpstart_, signal_type);
+
+  // Unflag the jumpstart of the gain as it should only happen once.
+  gain_jumpstart_ = false;
 
   // Apply the gain to the signal.
   int num_saturations = gain_applier_.Process(last_gain_, audio);
 
   // Estimate the gain that saturates the overall signal.
   saturating_gain_estimator_.Update(last_gain_, num_saturations);
 
   // Update the metrics.
   metrics_.Update(peak_level, noise_energy, last_gain_);
 
   data_dumper_->DumpRaw("lc_selected_gain", 1, &last_gain_);
   data_dumper_->DumpRaw("lc_noise_energy", 1, &noise_energy);
   data_dumper_->DumpRaw("lc_peak_level", 1, &peak_level);
   data_dumper_->DumpRaw("lc_saturating_gain", 1, &saturating_gain);
 
   data_dumper_->DumpWav("lc_output", audio->num_frames(),
                         audio->channels_f()[0], *sample_rate_hz_, 1);
 }
 
 }  // namespace webrtc