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/* Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009 Dean Beeler, Jerome Fisher
* Copyright (C) 2011, 2012, 2013, 2014 Dean Beeler, Jerome Fisher, Sergey V. Mikayev
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 2.1 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef MT32EMU_ANALOG_H
#define MT32EMU_ANALOG_H
#include "mt32emu.h"
namespace MT32Emu {
class AbstractLowPassFilter;
/* Analog class is dedicated to perform fair emulation of analogue circuitry of hardware units that is responsible
* for processing output signal after the DAC. It appears that the analogue circuit labeled "LPF" on the schematic
* also applies audible changes to the signal spectra. There is a significant boost of higher frequencies observed
* aside from quite poor attenuation of the mirror spectra above 16 kHz which is due to a relatively low filter order.
*
* As the final mixing of multiplexed output signal is performed after the DAC, this function is migrated here from Synth.
* Saying precisely, mixing is performed within the LPF as the entrance resistors are actually components of a LPF
* designed using the multiple feedback topology. Nevertheless, the schematic separates them.
*/
class Analog {
public:
Analog(AnalogOutputMode mode, const ControlROMFeatureSet *controlROMFeatures);
~Analog();
void process(Sample **outStream, const Sample *nonReverbLeft, const Sample *nonReverbRight, const Sample *reverbDryLeft, const Sample *reverbDryRight, const Sample *reverbWetLeft, const Sample *reverbWetRight, const Bit32u outLength);
unsigned int getOutputSampleRate() const;
Bit32u getDACStreamsLength(Bit32u outputLength) const;
void setSynthOutputGain(float synthGain);
void setReverbOutputGain(float reverbGain, bool mt32ReverbCompatibilityMode);
private:
AbstractLowPassFilter &leftChannelLPF;
AbstractLowPassFilter &rightChannelLPF;
SampleEx synthGain;
SampleEx reverbGain;
Analog(Analog &);
};
}
#endif
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