Reland of added functionality for specifying the initial signal level to use for the gain estimation

webrtc/modules/audio_processing/level_controller/level_controller.cc

Index: webrtc/modules/audio_processing/level_controller/level_controller.cc
diff --git a/webrtc/modules/audio_processing/level_controller/level_controller.cc b/webrtc/modules/audio_processing/level_controller/level_controller.cc
index c0edeb91c50f5a472019f07eb45ce97910d9ea12..939b0e8f2c0e757642715d1d284ac68589752e22 100644
--- a/webrtc/modules/audio_processing/level_controller/level_controller.cc
+++ b/webrtc/modules/audio_processing/level_controller/level_controller.cc
@@ -188,6 +188,11 @@ LevelController::LevelController()
 
 LevelController::~LevelController() {}
 
+void LevelController::SetInitialLevel(float level) {
+  peak_level_estimator_.SetInitialPeakLevel(level);
+  gain_jumpstart_ = true;
+}
+
 void LevelController::Initialize(int sample_rate_hz) {
   RTC_DCHECK(sample_rate_hz == AudioProcessing::kSampleRate8kHz ||
              sample_rate_hz == AudioProcessing::kSampleRate16kHz ||
@@ -240,8 +245,12 @@ void LevelController::Process(AudioBuffer* audio) {
   float saturating_gain = saturating_gain_estimator_.GetGain();
 
   // Compute the new gain to apply.
-  last_gain_ = gain_selector_.GetNewGain(long_term_peak_level, noise_energy,
-                                         saturating_gain, signal_type);
+  last_gain_ =
+      gain_selector_.GetNewGain(long_term_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);
@@ -262,17 +271,33 @@ void LevelController::Process(AudioBuffer* audio) {
                         audio->channels_f()[0], *sample_rate_hz_, 1);
 }
 
+void LevelController::ApplyConfig(
+    const AudioProcessing::Config::LevelController& config) {
+  if (config.initial_level) {
+    peak_level_estimator_.SetInitialPeakLevel(*config.initial_level);
+    gain_jumpstart_ = true;
+  }
+}
+
 std::string LevelController::ToString(
     const AudioProcessing::Config::LevelController& config) {
   std::stringstream ss;
   ss << "{"
-     << "enabled: " << (config.enabled ? "true" : "false") << "}";
+     << "enabled: " << (config.enabled ? "true" : "false") << ","
+     << "initial level: : ";
+  if (config.initial_level) {
+    ss << *config.initial_level;
+  } else {
+    ss << "Not specified";
+  }
+  ss << "}";
   return ss.str();
 }
 
 bool LevelController::Validate(
     const AudioProcessing::Config::LevelController& config) {
-  return true;
+  return !config.initial_level ||
+         (*config.initial_level < 0.1f && *config.initial_level > -100.1f);

[the sun, 2016/09/14 10:00:59]

Should you be comparing with an epsilon?

[peah-webrtc, 2016/09/16 07:11:07]

I added a variant of that. Please take another look to see whether it looks ok!

Done.

 }
 
 }  // namespace webrtc