Fixing UpdateLevel function in AEC.

webrtc/modules/audio_processing/aec/aec_core.cc

 /*
  *  Copyright (c) 2012 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 550 matching lines @@
 static float CalculatePower(const float* in, size_t num_samples) {
   size_t k;
   float energy = 0.0f;
 
   for (k = 0; k < num_samples; ++k) {
     energy += in[k] * in[k];
   }
   return energy / num_samples;
 }
 
-static void UpdateLevel(PowerLevel* level, float energy) {
-  level->sfrsum += energy;
+static void UpdateLevel(PowerLevel* level, float power) {
+  level->sfrsum += power;
   level->sfrcounter++;
 
   if (level->sfrcounter > subCountLen) {
-    level->framelevel = level->sfrsum / (subCountLen * PART_LEN);
+    level->framelevel = level->sfrsum / subCountLen;
     level->sfrsum = 0;
     level->sfrcounter = 0;
     if (level->framelevel > 0) {
       if (level->framelevel < level->minlevel) {
         level->minlevel = level->framelevel;  // New minimum.
       } else {
         level->minlevel *= (1 + 0.001f);  // Small increase.
       }
     }
     level->frcounter++;
     level->frsum += level->framelevel;
     if (level->frcounter > countLen) {
       level->averagelevel = level->frsum / countLen;
       level->frsum = 0;
       level->frcounter = 0;
     }
   }
 }
 
 static void UpdateMetrics(AecCore* aec) {
   float dtmp, dtmp2;
 
   const float actThresholdNoisy = 8.0f;
   const float actThresholdClean = 40.0f;
   const float safety = 0.99995f;
 
-  // To make noisePower consistent with the legacy code, a factor of
-  // 2.0f / PART_LEN2 is applied to noisyPower, since the legacy code uses
-  // the energy of a frame as the audio levels, while the new code uses a
-  // a per-sample energy (i.e., power).
-  const float noisyPower = 300000.0f * 2.0f / PART_LEN2;
+  const float noisyPower = 300000.0f;
 
   float actThreshold;
   float echo, suppressedEcho;
 
   if (aec->echoState) {  // Check if echo is likely present
     aec->stateCounter++;
   }
 
   if (aec->farlevel.frcounter == 0) {
     if (aec->farlevel.minlevel < noisyPower) {
@@ skipping 1278 matching lines @@
 
 int WebRtcAec_system_delay(AecCore* self) {
   return self->system_delay;
 }
 
 void WebRtcAec_SetSystemDelay(AecCore* self, int delay) {
   assert(delay >= 0);
   self->system_delay = delay;
 }
 }  // namespace webrtc