Arun Raghavan 753eada3aa Update audio_processing module
Corresponds to upstream commit 524e9b043e7e86fd72353b987c9d5f6a1ebf83e1

Update notes:

 * Pull in third party license file

 * Replace .gypi files with BUILD.gn to keep track of what changes
   upstream

 * Bunch of new filse pulled in as dependencies

 * Won't build yet due to changes needed on top of these
2015-10-15 16:18:45 +05:30

36 lines
1.0 KiB
C++

/*
* 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.
*/
#include "webrtc/modules/audio_processing/agc/utility.h"
#include <math.h>
static const double kLog10 = 2.30258509299;
static const double kLinear2DbScale = 20.0 / kLog10;
static const double kLinear2LoudnessScale = 13.4 / kLog10;
double Loudness2Db(double loudness) {
return loudness * kLinear2DbScale / kLinear2LoudnessScale;
}
double Linear2Loudness(double rms) {
if (rms == 0)
return -15;
return kLinear2LoudnessScale * log(rms);
}
double Db2Loudness(double db) {
return db * kLinear2LoudnessScale / kLinear2DbScale;
}
double Dbfs2Loudness(double dbfs) {
return Db2Loudness(90 + dbfs);
}