sintonia/ecasound-2.7.2/libecasound/audiofx_envelope_modulation...

263 lines
6.2 KiB
C++

// ------------------------------------------------------------------------
// audiofx_envelope-modulation.cpp: Effects which modify/modulate signal
// envelope
// Copyright (C) 2000 Rob Coker
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
// ------------------------------------------------------------------------
//
// History:
//
// 2003-08-21 Kai Vehmanen
// - Fixed a timing resolution bug in the envelope modulation code.
// This involved changing from float to fixed point presentation for
// the position counters to avoid loss of precision (led to unexpected
// drift in pulse timing).
// 2000-11-01 Rob Coker
// - Initial version.
//
// ------------------------------------------------------------------------
#include <cmath>
#include <kvu_message_item.h>
#include "samplebuffer_iterators.h"
#include "audiofx_envelope_modulation.h"
#include "eca-logger.h"
#include "eca-error.h"
EFFECT_ENV_MOD::~EFFECT_ENV_MOD(void)
{
}
EFFECT_PULSE_GATE::EFFECT_PULSE_GATE (parameter_t freq_Hz,
parameter_t onTime_percent)
{
set_parameter(1, freq_Hz);
set_parameter(2, onTime_percent);
freq_rep = 1.0;
on_time_rep = 0;
current_rep = 0;
period_rep = 0;
on_from_rep = 0;
}
EFFECT_PULSE_GATE::~EFFECT_PULSE_GATE(void)
{
}
void EFFECT_PULSE_GATE::set_samples_per_second(SAMPLE_SPECS::sample_rate_t v)
{
/* NOP, see audiofx.cpp:set_samples_per_second(); */
EFFECT_ENV_MOD::set_samples_per_second(v);
}
void EFFECT_PULSE_GATE::set_parameter(int param, parameter_t value)
{
switch (param) {
case 1:
if (value > 0)
{
freq_rep = value;
period_rep = static_cast<long int>(1.0f / freq_rep * samples_per_second() + 0.5f); // samples
}
else
{
MESSAGE_ITEM otemp;
otemp << "(audiofx_envelope_modulation) WARNING! Frequency must be greater than 0! ";
ECA_LOG_MSG(ECA_LOGGER::user_objects, otemp.to_string());
}
break;
case 2:
if ((value > 0) && (value < 100))
{
on_time_rep = value;
on_from_rep = static_cast<long int>((on_time_rep / 100.0) * period_rep + 0.5f);
}
else
{
MESSAGE_ITEM otemp;
otemp << "(audiofx_envelope_modulation) WARNING! on time must be between 0 and 100 inclusive! ";
ECA_LOG_MSG(ECA_LOGGER::user_objects, otemp.to_string());
}
break;
}
}
CHAIN_OPERATOR::parameter_t EFFECT_PULSE_GATE::get_parameter(int param) const
{
switch (param) {
case 1:
return(freq_rep);
case 2:
return (on_time_rep);
}
return(0.0);
}
void EFFECT_PULSE_GATE::init(SAMPLE_BUFFER* sbuf)
{
i.init(sbuf);
set_channels(sbuf->number_of_channels());
EFFECT_ENV_MOD::init(sbuf);
}
void EFFECT_PULSE_GATE::process(void)
{
i.begin(); // iterate through all samples, one sample-frame at a
// time (interleaved)
while(!i.end()) {
++current_rep;
if (current_rep >= period_rep) {
current_rep = 0;
}
if (current_rep > on_from_rep) {
for(int n = 0; n < channels(); n++) {
*i.current(n) = 0.0;
}
}
i.next();
}
}
EFFECT_PULSE_GATE_BPM::EFFECT_PULSE_GATE_BPM (parameter_t bpm,
parameter_t ontime_percent)
{
set_parameter(1, bpm);
set_parameter(2, ontime_percent);
}
EFFECT_PULSE_GATE_BPM::~EFFECT_PULSE_GATE_BPM(void)
{
}
void EFFECT_PULSE_GATE_BPM::set_parameter(int param, parameter_t value)
{
switch (param) {
case 1:
pulsegate_rep.set_parameter(1, value / 60.0f);
break;
case 2:
pulsegate_rep.set_parameter(2, value);
break;
}
}
CHAIN_OPERATOR::parameter_t EFFECT_PULSE_GATE_BPM::get_parameter(int param) const {
switch (param) {
case 1:
return (pulsegate_rep.get_parameter(1) * 60.0f);
break;
case 2:
return (pulsegate_rep.get_parameter(2));
break;
}
return(0.0);
}
void EFFECT_PULSE_GATE_BPM::init(SAMPLE_BUFFER* sbuf)
{
pulsegate_rep.init(sbuf);
EFFECT_ENV_MOD::init(sbuf);
}
void EFFECT_PULSE_GATE_BPM::process(void) { pulsegate_rep.process(); }
void EFFECT_PULSE_GATE_BPM::set_samples_per_second(SAMPLE_SPECS::sample_rate_t v)
{
pulsegate_rep.set_samples_per_second(v);
EFFECT_ENV_MOD::set_samples_per_second(v);
}
EFFECT_TREMOLO::EFFECT_TREMOLO (parameter_t freq_bpm,
parameter_t depth_percent)
{
set_parameter(1, freq_bpm);
set_parameter(2, depth_percent);
currentTime = 0.0;
}
EFFECT_TREMOLO::~EFFECT_TREMOLO(void)
{
}
void EFFECT_TREMOLO::set_parameter(int param, parameter_t value)
{
switch (param) {
case 1:
if (value > 0)
{
freq = value/(2*60); // convert from bpm to Hz
}
else
{
MESSAGE_ITEM otemp;
otemp << "(audiofx_envelope_modulation) WARNING! bpm must be greater than 0! ";
ECA_LOG_MSG(ECA_LOGGER::info, otemp.to_string());
}
break;
case 2:
depth = (value/100.0); // from percent to fraction
break;
}
}
CHAIN_OPERATOR::parameter_t EFFECT_TREMOLO::get_parameter(int param) const
{
switch (param) {
case 1:
return freq*120;
break;
case 2:
return depth*100.0;
break;
}
return(0.0);
}
void EFFECT_TREMOLO::init(SAMPLE_BUFFER* sbuf)
{
i.init(sbuf);
set_channels(sbuf->number_of_channels());
incrTime = 1.0/samples_per_second();
EFFECT_ENV_MOD::init(sbuf);
}
void EFFECT_TREMOLO::process(void)
{
i.begin(); // iterate through all samples, one sample-frame at a
// time (interleaved)
while(!i.end())
{
currentTime += incrTime;
double envelope = (1-depth)+depth*fabs(sin(2*3.1416*currentTime*freq));
if (envelope < 0)
{
envelope = 0;
}
for(int n = 0; n < channels(); n++)
{
*i.current(n) *= envelope;
}
i.next();
}
}