audio-algo-chunkware/audio/algo/chunkware/Gain.h

46 lines
1.7 KiB
C++

/**
* @author Bojan MARKOVIC
* @author Edouard DUPIN
* @copyright 2006, ChunkWare Music Software, OPEN-SOURCE
* @license BSD-1 (see license file)
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* * The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#pragma once
#include <etk/types.h>
namespace audio {
namespace algo {
namespace chunkware {
// linear -> dB conversion
static inline double lin2dB(double _lin) {
static const double LOG_2_DB = 8.6858896380650365530225783783321; // 20 / ln(10)
return log(_lin) * LOG_2_DB;
}
// dB -> linear conversion
static inline double dB2lin(double _dB) {
static const double DB_2_LOG = 0.11512925464970228420089957273422; // ln(10) / 20
return exp(_dB * DB_2_LOG);
}
}
}
}