57 lines
2.0 KiB
C
57 lines
2.0 KiB
C
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/*
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* Gain Functions (header)
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*
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* File : SimpleGain.h
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* Library : SimpleSource
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* Version : 1.12
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* Class :
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*
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* <EFBFBD> 2006, ChunkWare Music Software, OPEN-SOURCE
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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* DEALINGS IN THE SOFTWARE.
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*/
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#ifndef __SIMPLE_GAIN_H__
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#define __SIMPLE_GAIN_H__
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#include "SimpleHeader.h" // common header
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namespace chunkware_simple
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{
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//-------------------------------------------------------------
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// gain functions
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//-------------------------------------------------------------
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// linear -> dB conversion
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static INLINE double lin2dB( double lin ) {
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static const double LOG_2_DB = 8.6858896380650365530225783783321; // 20 / ln( 10 )
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return log( lin ) * LOG_2_DB;
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}
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// dB -> linear conversion
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static INLINE double dB2lin( double dB ) {
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static const double DB_2_LOG = 0.11512925464970228420089957273422; // ln( 10 ) / 20
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return exp( dB * DB_2_LOG );
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}
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} // end namespace chunkware_simple
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#endif // end __SIMPLE_GAIN_H__
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