Use VAD to get a better speech power estimation in the IntelligibilityEnhancer

webrtc/modules/audio_processing/intelligibility/intelligibility_utils.cc

Index: webrtc/modules/audio_processing/intelligibility/intelligibility_utils.cc
diff --git a/webrtc/modules/audio_processing/intelligibility/intelligibility_utils.cc b/webrtc/modules/audio_processing/intelligibility/intelligibility_utils.cc
index ed16a61e660e29283e71f0973b6c1b4b4eed46f6..821d15d0c8c38e3f3d3ff0d004e46e227563b891 100644
--- a/webrtc/modules/audio_processing/intelligibility/intelligibility_utils.cc
+++ b/webrtc/modules/audio_processing/intelligibility/intelligibility_utils.cc
@@ -31,28 +31,22 @@ float UpdateFactor(float target, float current, float limit) {
 
 PowerEstimator::PowerEstimator(size_t num_freqs,
                                float decay)
-    : magnitude_(new float[num_freqs]()),
-      power_(new float[num_freqs]()),
-      num_freqs_(num_freqs),
-      decay_(decay) {
-  memset(magnitude_.get(), 0, sizeof(*magnitude_.get()) * num_freqs_);
-  memset(power_.get(), 0, sizeof(*power_.get()) * num_freqs_);
-}
+    : power_(num_freqs, 0.f),
+      decay_(decay) {}
 
-// Compute the magnitude from the beginning, with exponential decaying of the
-// series data.
-void PowerEstimator::Step(const std::complex<float>* data) {
-  for (size_t i = 0; i < num_freqs_; ++i) {
-    magnitude_[i] = decay_ * magnitude_[i] +
-                (1.0f - decay_) * std::abs(data[i]);
+// Compute the power from the beginning, with exponential decaying of the series
+// data.
+void PowerEstimator::Step(const float* data) {

[turaj, 2016/02/13 00:09:43]

This is a utility class so I guess it is fine to be implemented like this. But
this is a bit dangerous implementation in the sense that one might call both
Step() methods and mess up with averaging. I guess what you need here is a
template class.

[hlundin-webrtc, 2016/02/15 13:05:12]

Acknowledged.

[aluebs-webrtc, 2016/02/19 03:56:31]

Done.

+  for (size_t i = 0; i < power_.size(); ++i) {

[turaj, 2016/02/13 00:09:43]

maybe a DCHECK that power_ and data are of the same size.

[hlundin-webrtc, 2016/02/15 13:05:12]

You don't know the size of |data|.

[aluebs-webrtc, 2016/02/19 03:56:31]

As Henrik points out, the size of data is unknown. If you think it is worth it I
can pass in the size as another parameter and DCHECK.

[turaj, 2016/02/19 16:48:47]

Sorry, my mistake, no I don't think it is necessary to pass the size.

+    power_[i] = decay_ * power_[i] + (1.f - decay_) * data[i] * data[i];
   }
 }
 
-const float* PowerEstimator::Power() {
-  for (size_t i = 0; i < num_freqs_; ++i) {
-    power_[i] = magnitude_[i] * magnitude_[i];
+void PowerEstimator::Step(const std::complex<float>* data) {
+  for (size_t i = 0; i < power_.size(); ++i) {

[turaj, 2016/02/13 00:09:43]

same comment as line 40.

+    power_[i] = decay_ * power_[i] +
+                (1.f - decay_) * std::abs(data[i]) * std::abs(data[i]);
   }
-  return &power_[0];
 }
 
 GainApplier::GainApplier(size_t freqs, float change_limit)