audio-algo-chunkware/audio/algo/chunkware/EnvelopeDetector.hpp

65 lines
2.2 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.hpp>
namespace audio {
namespace algo {
namespace chunkware {
// USE:
// 1. init envelope state to DC_OFFSET before processing
// 2. add to input before envelope runtime function
static const double DC_OFFSET = 1.0E-25;
class EnvelopeDetector {
public:
EnvelopeDetector(double _ms = 1.0,
double _sampleRate = 44100.0);
virtual ~EnvelopeDetector() {}
// time constant
virtual void setTc(double _ms);
virtual double getTc() const {
return m_timeMs;
}
// sample rate
virtual void setSampleRate(double _sampleRate);
virtual double getSampleRate() const {
return m_sampleRate;
}
// runtime function
void run(double _in, double& _state) {
_state = _in + m_coefficient * (_state - _in);
}
protected:
double m_sampleRate; //!< sample rate
double m_timeMs; //!< time constant in ms
double m_coefficient; //!< runtime coefficient
virtual void setCoef(); //!< coef calculation
};
}
}
}