MuseScore/fluid/voice.cpp
anatoly-os 0aa2511f3f fix #270803 messed playback for specific sounds
The reason was not updated minimal frames count and desync between different voices in playback as a result.
2018-03-29 13:48:27 +02:00

1909 lines
83 KiB
C++

/* FluidSynth - A Software Synthesizer
*
* Copyright (C) 2003 Peter Hanappe and others.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public License
* as published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
* 02111-1307, USA
*/
#include "conv.h"
#include "fluid.h"
#include "sfont.h"
#include "gen.h"
#include "voice.h"
namespace FluidS {
#define FLUID_SAMPLESANITY_CHECK (1 << 0)
#define FLUID_SAMPLESANITY_STARTUP (1 << 1)
#define fluid_clip(_val, _min, _max) \
{ (_val) = ((_val) < (_min))? (_min) : (((_val) > (_max))? (_max) : (_val)); }
/* used for filter turn off optimization - if filter cutoff is above the
specified value and filter q is below the other value, turn filter off */
#define FLUID_MAX_AUDIBLE_FILTER_FC 19000.0f
#define FLUID_MIN_AUDIBLE_FILTER_Q 1.2f
/* Smallest amplitude that can be perceived (full scale is +/- 0.5)
* 16 bits => 96+4=100 dB dynamic range => 0.00001
* 0.00001 * 2 is approximately 0.00003 :)
*/
#define FLUID_NOISE_FLOOR 0.00003
/* these should be the absolute minimum that FluidSynth can deal with */
#define FLUID_MIN_LOOP_SIZE 2
#define FLUID_MIN_LOOP_PAD 0
/* min vol envelope release (to stop clicks) in SoundFont timecents */
#define FLUID_MIN_VOLENVRELEASE -7200.0f /* ~16ms */
//---------------------------------------------------------
// triangle - calc value of triangle function for lfos
//---------------------------------------------------------
float triangle(int dur,int pos) {
pos += dur/4;
pos %= dur;
if (pos>dur/2)
return 2*(0.5-((pos/(0.5*dur))-1));
else
return 2*((pos/(0.5*dur))-0.5);
}
//---------------------------------------------------------
// samplesToNextTurningPoint
// calculate how many samples it is to the next change
// from rising to falling in a triangle function
//---------------------------------------------------------
int samplesToNextTurningPoint(int dur, int pos) {
pos += dur/4;
return ((dur/2)-(pos%(dur/2))) % (dur/2);
}
//---------------------------------------------------------
// Voice
//---------------------------------------------------------
Voice::Voice(Fluid* f)
{
_fluid = f;
status = FLUID_VOICE_OFF;
chan = NO_CHANNEL;
key = 0;
vel = 0;
channel = 0;
sample = 0;
/* The 'sustain' and 'finished' segments of the volume / modulation
* envelope are constant. They are never affected by any modulator
* or generator. Therefore it is enough to initialize them once
* during the lifetime of the synth.
*/
volenv_data[FLUID_VOICE_ENVSUSTAIN].count = 0xffffffff;
volenv_data[FLUID_VOICE_ENVSUSTAIN].coeff = 1.0f;
volenv_data[FLUID_VOICE_ENVSUSTAIN].incr = 0.0f;
volenv_data[FLUID_VOICE_ENVSUSTAIN].min = -1.0f;
volenv_data[FLUID_VOICE_ENVSUSTAIN].max = 2.0f;
volenv_data[FLUID_VOICE_ENVFINISHED].count = 0xffffffff;
volenv_data[FLUID_VOICE_ENVFINISHED].coeff = 0.0f;
volenv_data[FLUID_VOICE_ENVFINISHED].incr = 0.0f;
volenv_data[FLUID_VOICE_ENVFINISHED].min = -1.0f;
volenv_data[FLUID_VOICE_ENVFINISHED].max = 1.0f;
modenv_data[FLUID_VOICE_ENVSUSTAIN].count = 0xffffffff;
modenv_data[FLUID_VOICE_ENVSUSTAIN].coeff = 1.0f;
modenv_data[FLUID_VOICE_ENVSUSTAIN].incr = 0.0f;
modenv_data[FLUID_VOICE_ENVSUSTAIN].min = -1.0f;
modenv_data[FLUID_VOICE_ENVSUSTAIN].max = 2.0f;
modenv_data[FLUID_VOICE_ENVFINISHED].count = 0xffffffff;
modenv_data[FLUID_VOICE_ENVFINISHED].coeff = 0.0f;
modenv_data[FLUID_VOICE_ENVFINISHED].incr = 0.0f;
modenv_data[FLUID_VOICE_ENVFINISHED].min = -1.0f;
modenv_data[FLUID_VOICE_ENVFINISHED].max = 1.0f;
}
//---------------------------------------------------------
// init
// Initialize the synthesis process
//---------------------------------------------------------
void Voice::init(Sample* _sample, Channel* _channel, int _key, int _vel,
unsigned int _id, double tuning)
{
// Note: The voice parameters will be initialized later, when the
// generators have been retrieved from the sound font. Here, only
// the 'working memory' of the voice (position in envelopes, history
// of IIR filters, position in sample etc) is initialized.
id = _id;
_noteTuning = tuning;
chan = _channel->getNum();
key = _key;
vel = _vel;
channel = _channel;
mod_count = 0;
sample = _sample;
ticks = 0;
debug = 0;
has_looped = false; // Will be set during voice_write when the 2nd loop point is reached
last_fres = -1; // The filter coefficients have to be calculated later in the DSP loop.
filter_startup = 1; // Set the filter immediately, don't fade between old and new settings
interp_method = _channel->getInterpMethod();
// vol env initialization
volenv_count = 0;
volenv_section = 0;
volenv_val = 0.0f;
amp = 0.0f; // The last value of the volume envelope, used to
// calculate the volume increment during
// processing
// mod env initialization
modenv_count = 0;
modenv_section = 0;
modenv_val = 0.0f;
/* mod lfo */
modlfo_val = 0.0; // Fixme: Retrieve from any other existing
// voice on this channel to keep LFOs in
// unison?
modlfo_pos = 0;
/* vib lfo */
viblfo_val = 0.0f; // Fixme: See mod lfo
/* Clear sample history in filter */
hist1 = 0;
hist2 = 0;
/* Set all the generators to their default value, according to SF
* 2.01 section 8.1.3 (page 48). The value of NRPN messages are
* copied from the channel to the voice's generators. The sound font
* loader overwrites them. The generator values are later converted
* into voice parameters in calculate_runtime_synthesis_parameters.
*/
fluid_gen_init(&gen[0], channel);
/* For a looped sample, this value will be overwritten as soon as the
* loop parameters are initialized (they may depend on modulators).
* This value can be kept, it is a worst-case estimate.
*/
amplitude_that_reaches_noise_floor_nonloop = FLUID_NOISE_FLOOR;
amplitude_that_reaches_noise_floor_loop = FLUID_NOISE_FLOOR;
}
//---------------------------------------------------------
// gen_set
//---------------------------------------------------------
void Voice::gen_set(int i, float val)
{
gen[i].val = val;
gen[i].flags = GEN_SET;
}
//---------------------------------------------------------
// gen_incr
//---------------------------------------------------------
void Voice::gen_incr(int i, float val)
{
gen[i].val += val;
gen[i].flags = GEN_SET;
}
//---------------------------------------------------------
// gen_get
//---------------------------------------------------------
float Voice::gen_get(int g)
{
return gen[g].val;
}
inline void Voice::calcVolEnv(int n, fluid_env_data_t *env_data)
{
float x;
/* calculate the envelope value and check for valid range */
x = env_data->coeff * volenv_val + env_data->incr * n;
if (x < env_data->min)
x = env_data->min;
else if (x > env_data->max)
x = env_data->max;
volenv_val = x;
}
std::tuple<unsigned, bool> Voice::interpolateGeneratedDSPData(unsigned n)
{
dsp_buf.resize(n, 0.0f);
std::fill(dsp_buf.begin(), dsp_buf.end(), 0.0f);
unsigned generatedFrames = 0;
switch (interp_method) {
case FLUID_INTERP_NONE:
generatedFrames = dsp_float_interpolate_none(n);
break;
case FLUID_INTERP_LINEAR:
generatedFrames = dsp_float_interpolate_linear(n);
break;
case FLUID_INTERP_4THORDER:
default:
generatedFrames = dsp_float_interpolate_4th_order(n);
break;
case FLUID_INTERP_7THORDER:
generatedFrames = dsp_float_interpolate_7th_order(n);
break;
}
/* turn off voice if short count (sample ended and not looping) or voice reached noise floor*/
if (generatedFrames < n || positionToTurnOff > 0)
off();
bool needToRunBuffFilling = generatedFrames > 0;
return std::make_tuple(generatedFrames, needToRunBuffFilling);
}
bool Voice::generateDataForDSPChain(unsigned framesBufCount)
{
/* Range checking for sample- and loop-related parameters
* Initial phase is calculated here*/
check_sample_sanity();
/******************* vol env **********************/
fluid_env_data_t* env_data = &volenv_data[volenv_section];
Sample2AmpInc.clear();
std::map<int, int> sample2VolEnvSection;
std::set<int> volumeChanges;
if (volenv_section >= FLUID_VOICE_ENVFINISHED) {
off();
return false;
}
// determine points where volume envelope changes
unsigned curVolEnvCount = volenv_count;
unsigned restN = framesBufCount;
while (curVolEnvCount + restN >= env_data->count) {
restN -= env_data->count - curVolEnvCount;
sample2VolEnvSection.insert(std::pair<int, int>(framesBufCount - restN, volenv_section));
volumeChanges.insert(framesBufCount-restN);
curVolEnvCount = 0;
volenv_section++;
env_data = &volenv_data[volenv_section];
}
sample2VolEnvSection.insert(std::pair<int, int>(framesBufCount, volenv_section));
volumeChanges.insert(framesBufCount);
fluid_check_fpe ("voice_write vol env");
/******************* mod env **********************/
/* Skip to decay phase if delay and attack envelope sections each are
* less than 100 samples long. This avoids popping noises due to the
* mod envelope being out-of-sync with the sample-based volume envelope. */
if (modenv_section < 2 && modenv_data[FLUID_VOICE_ENVDELAY].count < 100 && modenv_data[FLUID_VOICE_ENVATTACK].count < 100) {
modenv_section = 2;
modenv_val = 1.0f;
}
env_data = &modenv_data[modenv_section];
/* skip to the next section of the envelope if necessary */
while (modenv_count >= env_data->count) {
env_data = &modenv_data[++modenv_section];
modenv_count = 0;
}
/* calculate the envelope value and check for valid range */
float x = env_data->coeff * modenv_val + env_data->incr * framesBufCount;
if (x < env_data->min) {
x = env_data->min;
modenv_section++;
modenv_count = 0;
}
else if (x > env_data->max) {
x = env_data->max;
modenv_section++;
modenv_count = 0;
}
modenv_val = x;
modenv_count += framesBufCount;
fluid_check_fpe ("voice_write mod env");
/******************* mod lfo **********************/
// calculate all points where we need to consider
// the mod lfo (where it changes its slope)
int modLfoStart = -1;
if (fabs(modlfo_to_vol) > 0) {
if (ticks >= modlfo_delay)
modLfoStart = 0;
else if (framesBufCount >= modlfo_delay)
modLfoStart = modlfo_delay;
if (modLfoStart >= 0) {
if (modLfoStart > 0)
volumeChanges.insert(modLfoStart);
unsigned int modLfoNextTurn = samplesToNextTurningPoint(modlfo_dur, modlfo_pos);
while (modLfoNextTurn+modLfoStart < framesBufCount) {
volumeChanges.insert(modLfoNextTurn+modLfoStart);
modLfoNextTurn++;
modLfoNextTurn += samplesToNextTurningPoint(modlfo_dur, modLfoNextTurn);
}
}
}
fluid_check_fpe ("voice_write mod LFO");
/******************* vib lfo **********************/
if (ticks >= viblfo_delay) {
viblfo_val += viblfo_incr * framesBufCount;
if (viblfo_val > (float) 1.0) {
viblfo_incr = -viblfo_incr;
viblfo_val = (float) 2.0 - viblfo_val;
}
else if (viblfo_val < -1.0) {
viblfo_incr = -viblfo_incr;
viblfo_val = (float) -2.0 - viblfo_val;
}
}
fluid_check_fpe ("voice_write Vib LFO");
/******************* amplitude **********************/
if (volenv_section == FLUID_VOICE_ENVDELAY) {
return false; /* The volume amplitude is in hold phase. No sound is produced. */
}
qreal oldTargetAmp = amp;
int lastPos = 0;
auto oldVolEnvSection = sample2VolEnvSection.begin();
auto curVolEnvSection = oldVolEnvSection;
for (auto curPos : volumeChanges)
{
if (modLfoStart >= 0 && curPos >= modLfoStart)
modlfo_val = triangle(modlfo_dur, modlfo_pos+curPos-modLfoStart);
else
modlfo_val = 0;
// never calculate anything for the very first sample
// everything should have been calculated in the last
// cycle - it would also cause a divion by zero later
if (curPos == 0) {
curPos = 1;
// if we should calculate for position 1 already make sure we don't do it twice
// could lead to curPos==lastPos which causes devision by zero
if (volumeChanges.find(1) != volumeChanges.end())
volumeChanges.erase(volumeChanges.find(1));
}
// just go to the next volume section if we're below last volume point
if (curPos >= curVolEnvSection->first && (unsigned int) curVolEnvSection->first < framesBufCount)
curVolEnvSection++;
volenv_count += curPos-lastPos;
calcVolEnv(curPos-lastPos, &volenv_data[oldVolEnvSection->second]);
volenv_section = oldVolEnvSection->second;
qreal target_amp {0.0}; /* target amplitude */
if (volenv_section <= FLUID_VOICE_ENVATTACK) {
/* the envelope is in the attack section: ramp linearly to max value.
* A positive modlfo_to_vol should increase volume (negative attenuation).
*/
target_amp = fluid_atten2amp (attenuation)
* fluid_cb2amp (modlfo_val * -modlfo_to_vol)
* volenv_val;
}
else {
//float amplitude_that_reaches_noise_floor;
//float amp_max;
target_amp = fluid_atten2amp (attenuation)
* fluid_cb2amp (960.0f * (1.0f - volenv_val)
+ modlfo_val * -modlfo_to_vol);
/* A voice can be turned off, when an estimate for the volume
* (upper bound) falls below that volume, that will drop the
* sample below the noise floor.
*/
/* If the loop amplitude is known, we can use it if the voice loop is within
* the sample loop
*/
float amplitude_that_reaches_noise_floor;
/* Is the playing pointer already in the loop? */
if (has_looped)
amplitude_that_reaches_noise_floor = amplitude_that_reaches_noise_floor_loop;
else
amplitude_that_reaches_noise_floor = amplitude_that_reaches_noise_floor_nonloop;
/* voice->attenuation_min is a lower boundary for the attenuation
* now and in the future (possibly 0 in the worst case). Now the
* amplitude of sample and volenv cannot exceed amp_max (since
* volenv_val can only drop):
*/
float amp_max = fluid_atten2amp (min_attenuation_cB) * volenv_val;
/* And if amp_max is already smaller than the known amplitude,
* which will attenuate the sample below the noise floor, then we
* can safely turn off the voice. Duh. */
if (amp_max < amplitude_that_reaches_noise_floor) {
positionToTurnOff = curPos;
}
}
if (curVolEnvSection->second != oldVolEnvSection->second) {
if (oldVolEnvSection->second == FLUID_VOICE_ENVDECAY) {
env_data = &volenv_data[oldVolEnvSection->second];
volenv_val = env_data->min * env_data->coeff;
}
volenv_count = 0;
oldVolEnvSection = curVolEnvSection;
}
/* Volume increment to go from voice->amp to target_amp in FLUID_BUFSIZE steps */
amp_incr = (target_amp - oldTargetAmp) / (curPos - lastPos);
lastPos = curPos;
Sample2AmpInc.insert(std::pair<int, qreal>(curPos, amp_incr));
// if voice is turned off after this no need to calculate any more values
if (positionToTurnOff > 0)
break;
oldTargetAmp = target_amp;
}
if (modLfoStart >= 0) {
modlfo_pos += framesBufCount - modLfoStart;
modlfo_val = triangle(modlfo_dur, modlfo_pos-modLfoStart);
}
fluid_check_fpe ("voice_write amplitude calculation");
/* Calculate the number of samples, that the DSP loop advances
* through the original waveform with each step in the output
* buffer. It is the ratio between the frequencies of original
* waveform and output waveform.*/
{
float cent = pitch + modlfo_val * modlfo_to_pitch
+ viblfo_val * viblfo_to_pitch
+ modenv_val * modenv_to_pitch;
phase_incr = _fluid->ct2hz_real(cent) / root_pitch_hz;
}
/* if phase_incr is not advancing, set it to the minimum fraction value (prevent stuckage) */
if (phase_incr == 0)
phase_incr = 1;
/*************** resonant filter ******************/
/* calculate the frequency of the resonant filter in Hz */
float _fres = _fluid->ct2hz_real(fres
+ modlfo_val * modlfo_to_fc
+ modenv_val * modenv_to_fc);
/* FIXME - Still potential for a click during turn on, can we interpolate
between 20khz cutoff and 0 Q? */
/* I removed the optimization of turning the filter off when the
* resonance frequence is above the maximum frequency. Instead, the
* filter frequency is set to a maximum of 0.45 times the sampling
* rate. For a 44100 kHz sampling rate, this amounts to 19845
* Hz. The reason is that there were problems with anti-aliasing when the
* synthesizer was run at lower sampling rates. Thanks to Stephan
* Tassart for pointing me to this bug. By turning the filter on and
* clipping the maximum filter frequency at 0.45*srate, the filter
* is used as an anti-aliasing filter. */
if (_fres > 0.45f * _fluid->sample_rate)
_fres = 0.45f * _fluid->sample_rate;
else if (_fres < 5)
_fres = 5;
/* if filter enabled and there is a significant frequency change.. */
if ((qAbs(_fres - last_fres) > 0.01)) {
/* The filter coefficients have to be recalculated (filter
* parameters have changed). Recalculation for various reasons is
* forced by setting last_fres to -1. The flag filter_startup
* indicates, that the DSP loop runs for the first time, in this
* case, the filter is set directly, instead of smoothly fading
* between old and new settings.
*
* Those equations from Robert Bristow-Johnson's `Cookbook
* formulae for audio EQ biquad filter coefficients', obtained
* from Harmony-central.com / Computer / Programming. They are
* the result of the bilinear transform on an analogue filter
* prototype. To quote, `BLT frequency warping has been taken
* into account for both significant frequency relocation and for
* bandwidth readjustment'. */
float omega = (float) (2.0 * M_PI * (_fres / ((float) _fluid->sample_rate)));
float sin_coeff = (float) sin(omega);
float cos_coeff = (float) cos(omega);
float alpha_coeff = sin_coeff / (2.0f * q_lin);
float a0_inv = 1.0f / (1.0f + alpha_coeff);
/* Calculate the filter coefficients. All coefficients are
* normalized by a0. Think of `a1' as `a1/a0'.
*
* Here a couple of multiplications are saved by reusing common expressions.
* The original equations should be:
* b0=(1.-cos_coeff)*a0_inv*0.5*voice->filter_gain;
* b1=(1.-cos_coeff)*a0_inv*voice->filter_gain;
* b2=(1.-cos_coeff)*a0_inv*0.5*voice->filter_gain; */
float a1_temp = -2.0f * cos_coeff * a0_inv;
float a2_temp = (1.0f - alpha_coeff) * a0_inv;
float b1_temp = (1.0f - cos_coeff) * a0_inv * filter_gain;
/* both b0 -and- b2 */
float b02_temp = b1_temp * 0.5f;
if (filter_startup) {
/* The filter is calculated, because the voice was started up.
* In this case set the filter coefficients without delay.
*/
a1 = a1_temp;
a2 = a2_temp;
b02 = b02_temp;
b1 = b1_temp;
filter_coeff_incr_count = 0;
filter_startup = 0;
// printf("Setting initial filter coefficients.\n");
}
else {
/* The filter frequency is changed. Calculate an increment
* factor, so that the new setting is reached after one buffer
* length. x_incr is added to the current value FLUID_BUFSIZE
* times. The length is arbitrarily chosen. Longer than one
* buffer will sacrifice some performance, though. Note: If
* the filter is still too 'grainy', then increase this number
* at will.
*/
#define FILTER_TRANSITION_SAMPLES 64 // (FLUID_BUFSIZE)
a1_incr = (a1_temp - a1) / FILTER_TRANSITION_SAMPLES;
a2_incr = (a2_temp - a2) / FILTER_TRANSITION_SAMPLES;
b02_incr = (b02_temp - b02) / FILTER_TRANSITION_SAMPLES;
b1_incr = (b1_temp - b1) / FILTER_TRANSITION_SAMPLES;
/* Have to add the increments filter_coeff_incr_count times. */
filter_coeff_incr_count = FILTER_TRANSITION_SAMPLES;
}
last_fres = _fres;
fluid_check_fpe ("voice_write filter calculation");
}
fluid_check_fpe ("voice_write DSP coefficients");
return true;
}
static float* shiftBufferPosition(unsigned shift, float* buff)
{
float* resBuffPosition = buff;
for (unsigned i = 0; i < shift; ++i) {
++resBuffPosition; //left channel
++resBuffPosition; //right channel
}
return resBuffPosition;
}
//-----------------------------------------------------------------------------
// write
//
// This is where it all happens. This function is called by the
// synthesizer to generate the sound samples. The synthesizer passes
// four audio buffers: left, right, reverb out, and chorus out.
//
// The biggest part of this function sets the correct values for all
// the dsp parameters (all the control data boil down to only a few
// dsp parameters). The dsp routine is #included in several places (fluid_dsp_core.c).
//-----------------------------------------------------------------------------
void Voice::write(unsigned n, float* out, float* reverb, float* chorus)
{
/* make sure we're playing and that we have sample data */
if (!PLAYING())
return;
if (!sample) {
printf("!sample\n");
off();
return;
}
/*
/ ------- CACHING ALGORITHM -------
/ If cached frames exist and number of required frames is less than cache size
/ apply effects to the required number of frames from cache, put cache to buffer
/ Else
/ put all cached frames to buffer
/ (buffer* is a buffer after putting left cache data)
/ generate DSP data and interpolation for buffer* size data or required buffer size if buffer* is too small
/ fill cache data with raw buffer* data
/ apply effects to cache and put cache data to raw buffer*
*/
if (n <= _cachedFrames) {
effects(_initialCacheFrames - _cachedFrames, n, out, reverb, chorus);
_cachedFrames -= n;
}
else {
const unsigned leftBufferFramesToFill = n - _cachedFrames; //must be called before setting null to _cachedFrames
unsigned buffShiftAfterApplyingCache = 0;
if (_cachedFrames > 0) {
buffShiftAfterApplyingCache = _cachedFrames;
effects(_initialCacheFrames - _cachedFrames, _cachedFrames, out, reverb, chorus);
_cachedFrames = 0;
}
const unsigned requiredNumberOfFramesToGenerateEnvelope = FLUID_VOICE_ENVLAST * volenv_data[FLUID_VOICE_ENVDELAY].count;
const unsigned framesToGenerateData = std::max(leftBufferFramesToFill, requiredNumberOfFramesToGenerateEnvelope);
if (generateDataForDSPChain(framesToGenerateData)) {
auto interpolationRes = interpolateGeneratedDSPData(framesToGenerateData);
if (std::get<1>(interpolationRes)) {
_initialCacheFrames = std::get<0>(interpolationRes);
float* shiftedOut = shiftBufferPosition(buffShiftAfterApplyingCache, out);
float* shiftedReverb = shiftBufferPosition(buffShiftAfterApplyingCache, reverb);
float* shiftedChorus = shiftBufferPosition(buffShiftAfterApplyingCache, chorus);
effects(0, leftBufferFramesToFill, shiftedOut, shiftedReverb, shiftedChorus);
_cachedFrames = _initialCacheFrames;
_cachedFrames -= std::min(leftBufferFramesToFill, _cachedFrames); //to keep positive
}
}
}
ticks += n;
}
//---------------------------------------------------------
// voice_start
//---------------------------------------------------------
void Voice::voice_start()
{
/* The maximum volume of the loop is calculated and cached once for each
* sample with its nominal loop settings. This happens, when the sample is used
* for the first time.*/
/*
* in this function we calculate the values of all the parameters. the
* parameters are converted to their most useful unit for the DSP
* algorithm, for example, number of samples instead of
* timecents. Some parameters keep their "perceptual" unit and
* conversion will be done in the DSP function. This is the case, for
* example, for the pitch since it is modulated by the controllers in
* cents. */
static const int list_of_generators_to_initialize[35] = {
GEN_STARTADDROFS, // SF2.01 page 48 #0
GEN_ENDADDROFS, // #1
GEN_STARTLOOPADDROFS, // #2
GEN_ENDLOOPADDROFS, // #3
// GEN_STARTADDRCOARSEOFS see comment below [1] #4
GEN_MODLFOTOPITCH, // #5
GEN_VIBLFOTOPITCH, // #6
GEN_MODENVTOPITCH, // #7
GEN_FILTERFC, // #8
GEN_FILTERQ, // #9
GEN_MODLFOTOFILTERFC, // #10
GEN_MODENVTOFILTERFC, // #11
// GEN_ENDADDRCOARSEOFS [1] #12
GEN_MODLFOTOVOL, // #13
// not defined #14
GEN_CHORUSSEND, // #15
GEN_REVERBSEND, // #16
GEN_PAN, // #17
// not defined #18
// not defined #19
// not defined #20
GEN_MODLFODELAY, // #21
GEN_MODLFOFREQ, // #22
GEN_VIBLFODELAY, // #23
GEN_VIBLFOFREQ, // #24
GEN_MODENVDELAY, // #25
GEN_MODENVATTACK, // #26
GEN_MODENVHOLD, // #27
GEN_MODENVDECAY, // #28
// GEN_MODENVSUSTAIN [1] #29
GEN_MODENVRELEASE, // #30
// GEN_KEYTOMODENVHOLD [1] #31
// GEN_KEYTOMODENVDECAY [1] #32
GEN_VOLENVDELAY, // #33
GEN_VOLENVATTACK, // #34
GEN_VOLENVHOLD, // #35
GEN_VOLENVDECAY, // #36
// GEN_VOLENVSUSTAIN [1] #37
GEN_VOLENVRELEASE, // #38
// GEN_KEYTOVOLENVHOLD [1] #39
// GEN_KEYTOVOLENVDECAY [1] #40
// GEN_STARTLOOPADDRCOARSEOFS [1] #45
GEN_KEYNUM, // #46
GEN_VELOCITY, // #47
GEN_ATTENUATION, // #48
// GEN_ENDLOOPADDRCOARSEOFS [1] #50
// GEN_COARSETUNE [1] #51
// GEN_FINETUNE [1] #52
GEN_OVERRIDEROOTKEY, // #58
GEN_PITCH, // ---
-1 // end-of-list marker
};
/* When the voice is made ready for the synthesis process, a lot of
* voice-internal parameters have to be calculated.
*
* At this point, the sound font has already set the -nominal- value
* for all generators (excluding GEN_PITCH). Most generators can be
* modulated - they include a nominal value and an offset (which
* changes with velocity, note number, channel parameters like
* aftertouch, mod wheel...) Now this offset will be calculated as
* follows:
*
* - Process each modulator once.
* - Calculate its output value.
* - Find the target generator.
* - Add the output value to the modulation value of the generator.
*
* Note: The generators have been initialized with
* fluid_gen_set_default_values.
*/
for (int i = 0; i < mod_count; i++) {
Mod* m = &mod[i];
float modval = m->get_value(channel, this);
int dest_gen_index = m->dest;
Generator* dest_gen = &gen[dest_gen_index];
dest_gen->mod += modval;
}
/* Now the generators are initialized, nominal and modulation value.
* The voice parameters (which depend on generators) are calculated
* with update_param. Processing the list of generator
* changes will calculate each voice parameter once.
*
* Note [1]: Some voice parameters depend on several generators. For
* example, the pitch depends on GEN_COARSETUNE, GEN_FINETUNE and
* GEN_PITCH. voice->pitch. Unnecessary recalculation is avoided
* by removing all but one generator from the list of voice
* parameters. Same with GEN_XXX and GEN_XXXCOARSE: the
* initialisation list contains only GEN_XXX.
*/
/* Calculate the voice parameter(s) dependent on each generator. */
for (int i = 0; list_of_generators_to_initialize[i] != -1; i++)
update_param(list_of_generators_to_initialize[i]);
/* Make an estimate on how loud this voice can get at any time (attenuation). */
min_attenuation_cB = get_lower_boundary_for_attenuation();
// qDebug("DELAY (%d) %d", FLUID_VOICE_ENVDELAY,volenv_data[FLUID_VOICE_ENVDELAY].count);
// qDebug("ATTACK (%d) %d", FLUID_VOICE_ENVATTACK,volenv_data[FLUID_VOICE_ENVATTACK].count);
// qDebug("HOLD (%d) %d", FLUID_VOICE_ENVHOLD, volenv_data[FLUID_VOICE_ENVHOLD].count);
// qDebug("DECAY (%d) %d", FLUID_VOICE_ENVDECAY, volenv_data[FLUID_VOICE_ENVDECAY].count);
// qDebug("SUSTAIN (%d) %d", FLUID_VOICE_ENVSUSTAIN, volenv_data[FLUID_VOICE_ENVSUSTAIN].count);
// qDebug("RELEASE (%d) %d", FLUID_VOICE_ENVRELEASE, volenv_data[FLUID_VOICE_ENVRELEASE].count);
/* Force setting of the phase at the first DSP loop run
* This cannot be done earlier, because it depends on modulators.
*/
check_sample_sanity_flag = FLUID_SAMPLESANITY_STARTUP;
positionToTurnOff = -1;
status = FLUID_VOICE_ON;
}
//---------------------------------------------------------
// fluid_voice_calculate_gen_pitch
//---------------------------------------------------------
void Voice::calculate_gen_pitch()
{
float x;
/* The GEN_PITCH is a hack to fit the pitch bend controller into the
* modulator paradigm. Now the nominal pitch of the key is set.
* Note about SCALETUNE: SF2.01 8.1.3 says, that this generator is a
* non-realtime parameter. So we don't allow modulation (as opposed
* to _GEN(voice, GEN_SCALETUNE) When the scale tuning is varied,
* one key remains fixed. Here C3 (MIDI number 60) is used.
*/
//if (channel->tuning != 0) {
/* pitch(scalekey) + scale * (pitch(key) - pitch(scalekey)) */
x = _fluid->getPitch((int)(root_pitch / 100.0f));
gen[GEN_PITCH].val = _noteTuning + (x + (gen[GEN_SCALETUNE].val / 100.0f * (_fluid->getPitch(key) - x)));
// }
//else {
// gen[GEN_PITCH].val = _noteTuning + (gen[GEN_SCALETUNE].val * (key - root_pitch / 100.0f) + root_pitch);
// }
}
/*
* calculate_hold_decay_frames
*/
int Voice::calculate_hold_decay_frames(int gen_base, int gen_key2base, int is_decay)
{
/* Purpose:
*
* Returns the number of DSP loops, that correspond to the hold
* (is_decay=0) or decay (is_decay=1) time.
* gen_base=GEN_VOLENVHOLD, GEN_VOLENVDECAY, GEN_MODENVHOLD,
* GEN_MODENVDECAY gen_key2base=GEN_KEYTOVOLENVHOLD,
* GEN_KEYTOVOLENVDECAY, GEN_KEYTOMODENVHOLD, GEN_KEYTOMODENVDECAY
*
* SF2.01 section 8.4.3 # 31, 32, 39, 40
* GEN_KEYTOxxxENVxxx uses key 60 as 'origin'.
* The unit of the generator is timecents per key number.
* If KEYTOxxxENVxxx is 100, a key one octave over key 60 (72)
* will cause (60-72)*100=-1200 timecents of time variation.
* The time is cut in half.
*/
float timecents = (GEN(gen_base) + GEN(gen_key2base) * (60.0 - key));
/* Range checking */
if (is_decay){
/* SF 2.01 section 8.1.3 # 28, 36 */
if (timecents > 8000.0)
timecents = 8000.0;
}
else {
/* SF 2.01 section 8.1.3 # 27, 35 */
if (timecents > 5000)
timecents = 5000.0;
/* SF 2.01 section 8.1.2 # 27, 35:
* The most negative number indicates no hold time
*/
if (timecents <= -32768.)
return 0;
}
/* SF 2.01 section 8.1.3 # 27, 28, 35, 36 */
if (timecents < -12000.0)
timecents = -12000.0;
float seconds = fluid_tc2sec(timecents);
return (int)((float)_fluid->sample_rate * seconds);
}
/*
* update_param
*
* Purpose:
*
* The value of a generator (gen) has changed. (The different
* generators are listed in fluid.h, or in SF2.01 page 48-49)
* Now the dependent 'voice' parameters are calculated.
*
* fluid_voice_update_param can be called during the setup of the
* voice (to calculate the initial value for a voice parameter), or
* during its operation (a generator has been changed due to
* real-time parameter modifications like pitch-bend).
*
* Note: The generator holds three values: The base value .val, an
* offset caused by modulators .mod, and an offset caused by the
* NRPN system. _GEN(voice, generator_enumerator) returns the sum
* of all three.
*/
void Voice::update_param(int _gen)
{
double q_dB;
float x;
float y;
unsigned int count;
// Alternate attenuation scale used by EMU10K1 cards when setting the attenuation at the preset or instrument level within the SoundFont bank.
static const float ALT_ATTENUATION_SCALE = 0.4;
double gain = 1.0 / 32768.0f;
switch (_gen) {
case GEN_PAN:
/* range checking is done in the fluid_pan function */
pan = GEN(GEN_PAN);
amp_left = fluid_pan(pan, 1) * gain;
amp_right = fluid_pan(pan, 0) * gain;
break;
case GEN_ATTENUATION:
attenuation = gen[GEN_ATTENUATION].val * ALT_ATTENUATION_SCALE + gen[GEN_ATTENUATION].mod + gen[GEN_ATTENUATION].nrpn;
/* Range: SF2.01 section 8.1.3 # 48
* Motivation for range checking:
* OHPiano.SF2 sets initial attenuation to a whooping -96 dB
*/
attenuation = qBound(0.0f, attenuation, 1440.0f);
break;
/* The pitch is calculated from three different generators.
* Read comment in fluid.h about GEN_PITCH.
*/
case GEN_PITCH:
case GEN_COARSETUNE:
case GEN_FINETUNE:
/* The testing for allowed range is done in 'fluid_ct2hz' */
pitch = GEN(GEN_PITCH) + 100.0f * GEN(GEN_COARSETUNE) + GEN(GEN_FINETUNE);
break;
case GEN_REVERBSEND:
/* The generator unit is 'tenths of a percent'. */
// reverb_send = GEN(GEN_REVERBSEND) / 1000.0f;
reverb_send = float(channel->cc[EFFECTS_DEPTH1]) / 128.0;
// fluid_clip(reverb_send, 0.0, 1.0);
amp_reverb = reverb_send * gain;
break;
case GEN_CHORUSSEND:
/* The generator unit is 'tenths of a percent'. */
chorus_send = GEN(GEN_CHORUSSEND) / 1000.0f;
fluid_clip(chorus_send, 0.0, 1.0);
amp_chorus = chorus_send * gain;
break;
case GEN_OVERRIDEROOTKEY:
/* This is a non-realtime parameter. Therefore the .mod part of the generator
* can be neglected.
* NOTE: origpitch sets MIDI root note while pitchadj is a fine tuning amount
* which offsets the original rate. This means that the fine tuning is
* inverted with respect to the root note (so subtract it, not add).
*/
if (sample != 0) {
if (gen[GEN_OVERRIDEROOTKEY].val > -1) { //FIXME: use flag instead of -1
root_pitch = gen[GEN_OVERRIDEROOTKEY].val * 100.0f - sample->pitchadj;
}
else {
root_pitch = sample->origpitch * 100.0f - sample->pitchadj;
}
root_pitch_hz = _fluid->ct2hz(root_pitch);
root_pitch_hz *= (float) _fluid->sample_rate / sample->samplerate;
/* voice pitch depends on voice root_pitch, so calculate voice pitch now */
calculate_gen_pitch();
}
break;
case GEN_FILTERFC:
/* The resonance frequency is converted from absolute cents to
* midicents .val and .mod are both used, this permits real-time
* modulation. The allowed range is tested in the 'fluid_ct2hz'
* function [PH,20021214]
*/
fres = GEN(GEN_FILTERFC);
/* The synthesis loop will have to recalculate the filter
* coefficients. */
last_fres = -1.0f;
break;
case GEN_FILTERQ:
/* The generator contains 'centibels' (1/10 dB) => divide by 10 to
* obtain dB
*/
q_dB = GEN(GEN_FILTERQ) / 10.0f;
/* Range: SF2.01 section 8.1.3 # 8 (convert from cB to dB => /10) */
fluid_clip(q_dB, 0.0f, 96.0f);
/* Short version: Modify the Q definition in a way, that a Q of 0
* dB leads to no resonance hump in the freq. response.
*
* Long version: From SF2.01, page 39, item 9 (initialFilterQ):
* "The gain at the cutoff frequency may be less than zero when
* zero is specified". Assume q_dB=0 / q_lin=1: If we would leave
* q as it is, then this results in a 3 dB hump slightly below
* fc. At fc, the gain is exactly the DC gain (0 dB). What is
* (probably) meant here is that the filter does not show a
* resonance hump for q_dB=0. In this case, the corresponding
* q_lin is 1/sqrt(2)=0.707. The filter should have 3 dB of
* attenuation at fc now. In this case Q_dB is the height of the
* resonance peak not over the DC gain, but over the frequency
* response of a non-resonant filter. This idea is implemented as
* follows:
*/
q_dB -= 3.01f;
/* The 'sound font' Q is defined in dB. The filter needs a linear
q. Convert.
*/
q_lin = (float) (pow(10.0f, q_dB / 20.0f));
/* SF 2.01 page 59:
*
* The SoundFont specs ask for a gain reduction equal to half the
* height of the resonance peak (Q). For example, for a 10 dB
* resonance peak, the gain is reduced by 5 dB. This is done by
* multiplying the total gain with sqrt(1/Q). `Sqrt' divides dB
* by 2 (100 lin = 40 dB, 10 lin = 20 dB, 3.16 lin = 10 dB etc)
* The gain is later factored into the 'b' coefficients
* (numerator of the filter equation). This gain factor depends
* only on Q, so this is the right place to calculate it.
*/
filter_gain = (float) (1.0 / sqrt(q_lin));
/* The synthesis loop will have to recalculate the filter coefficients. */
last_fres = -1.;
break;
case GEN_MODLFOTOPITCH:
modlfo_to_pitch = GEN(GEN_MODLFOTOPITCH);
fluid_clip(modlfo_to_pitch, -12000.0, 12000.0);
break;
case GEN_MODLFOTOVOL:
modlfo_to_vol = GEN(GEN_MODLFOTOVOL);
fluid_clip(modlfo_to_vol, -960.0, 960.0);
break;
case GEN_MODLFOTOFILTERFC:
modlfo_to_fc = GEN(GEN_MODLFOTOFILTERFC);
fluid_clip(modlfo_to_fc, -12000, 12000);
break;
case GEN_MODLFODELAY:
x = GEN(GEN_MODLFODELAY);
fluid_clip(x, -12000.0f, 5000.0f);
modlfo_delay = (unsigned int) (_fluid->sample_rate * fluid_tc2sec_delay(x));
break;
case GEN_MODLFOFREQ:
{
/* - the frequency is converted into a delta value, per frame
* - the delay into a sample delay
*/
unsigned int old_modlfo_dur = modlfo_dur;
x = GEN(GEN_MODLFOFREQ);
fluid_clip(x, -16000.0f, 4500.0f);
modlfo_dur = _fluid->sample_rate / fluid_act2hz(x);
if (old_modlfo_dur > 0)
modlfo_pos = (modlfo_pos/old_modlfo_dur) * modlfo_dur;
break;
}
case GEN_VIBLFOFREQ:
/* vib lfo
*
* - the frequency is converted into a delta value per frame
* - the delay into a sample delay
*/
x = GEN(GEN_VIBLFOFREQ);
fluid_clip(x, -16000.0f, 4500.0f);
viblfo_incr = (4.0f * fluid_act2hz(x) / _fluid->sample_rate);
break;
case GEN_VIBLFODELAY:
x = GEN(GEN_VIBLFODELAY);
fluid_clip(x, -12000.0f, 5000.0f);
viblfo_delay = (unsigned int) (_fluid->sample_rate * fluid_tc2sec_delay(x));
break;
case GEN_VIBLFOTOPITCH:
viblfo_to_pitch = GEN(GEN_VIBLFOTOPITCH);
fluid_clip(viblfo_to_pitch, -12000.0, 12000.0);
break;
case GEN_KEYNUM:
/* GEN_KEYNUM: SF2.01 page 46, item 46
*
* If this generator is active, it forces the key number to its
* value. Non-realtime controller.
*
* There is a flag, which should indicate, whether a generator is
* enabled or not. But here we rely on the default value of -1.
*/
x = GEN(GEN_KEYNUM);
if (x >= 0)
key = x;
break;
case GEN_VELOCITY:
/* GEN_VELOCITY: SF2.01 page 46, item 47
*
* If this generator is active, it forces the velocity to its
* value. Non-realtime controller.
*
* There is a flag, which should indicate, whether a generator is
* enabled or not. But here we rely on the default value of -1.
*/
x = GEN(GEN_VELOCITY);
if (x > 0)
vel = x;
break;
case GEN_MODENVTOPITCH:
modenv_to_pitch = GEN(GEN_MODENVTOPITCH);
fluid_clip(modenv_to_pitch, -12000.0, 12000.0);
break;
case GEN_MODENVTOFILTERFC:
modenv_to_fc = GEN(GEN_MODENVTOFILTERFC);
/* Range: SF2.01 section 8.1.3 # 1
* Motivation for range checking:
* Filter is reported to make funny noises now and then
*/
fluid_clip(modenv_to_fc, -12000.0, 12000.0);
break;
/* sample start and ends points
*
* Range checking is initiated via the
* check_sample_sanity flag,
* because it is impossible to check here:
* During the voice setup, all modulators are processed, while
* the voice is inactive. Therefore, illegal settings may
* occur during the setup (for example: First move the loop
* end point ahead of the loop start point => invalid, then
* move the loop start point forward => valid again.
*/
case GEN_STARTADDROFS: /* SF2.01 section 8.1.3 # 0 */
case GEN_STARTADDRCOARSEOFS: /* SF2.01 section 8.1.3 # 4 */
if (sample != 0) {
start = (sample->start
+ (int) GEN(GEN_STARTADDROFS)
+ 32768 * (int) GEN(GEN_STARTADDRCOARSEOFS));
check_sample_sanity_flag = FLUID_SAMPLESANITY_CHECK;
}
break;
case GEN_ENDADDROFS: /* SF2.01 section 8.1.3 # 1 */
case GEN_ENDADDRCOARSEOFS: /* SF2.01 section 8.1.3 # 12 */
if (sample != 0) {
end = (sample->end
+ (int) GEN(GEN_ENDADDROFS)
+ 32768 * (int) GEN(GEN_ENDADDRCOARSEOFS));
check_sample_sanity_flag = FLUID_SAMPLESANITY_CHECK;
}
break;
case GEN_STARTLOOPADDROFS: /* SF2.01 section 8.1.3 # 2 */
case GEN_STARTLOOPADDRCOARSEOFS: /* SF2.01 section 8.1.3 # 45 */
if (sample != 0) {
loopstart = (sample->loopstart
+ (int) GEN(GEN_STARTLOOPADDROFS)
+ 32768 * (int) GEN(GEN_STARTLOOPADDRCOARSEOFS));
check_sample_sanity_flag = FLUID_SAMPLESANITY_CHECK;
}
break;
case GEN_ENDLOOPADDROFS: /* SF2.01 section 8.1.3 # 3 */
case GEN_ENDLOOPADDRCOARSEOFS: /* SF2.01 section 8.1.3 # 50 */
if (sample != 0) {
loopend = (sample->loopend
+ (int) GEN(GEN_ENDLOOPADDROFS)
+ 32768 * (int) GEN(GEN_ENDLOOPADDRCOARSEOFS));
check_sample_sanity_flag = FLUID_SAMPLESANITY_CHECK;
}
break;
/* Conversion functions differ in range limit */
#define NUM_FRAMES_DELAY(_v) (unsigned int) (_fluid->sample_rate * fluid_tc2sec_delay(_v))
#define NUM_FRAMES_ATTACK(_v) (unsigned int) (_fluid->sample_rate * fluid_tc2sec_attack(_v))
#define NUM_FRAMES_RELEASE(_v) (unsigned int) (_fluid->sample_rate * fluid_tc2sec_release(_v))
/* volume envelope
*
* - delay and hold times are converted to absolute number of samples
* - sustain is converted to its absolute value
* - attack, decay and release are converted to their increment per sample
*/
case GEN_VOLENVDELAY: /* SF2.01 section 8.1.3 # 33 */
x = GEN(GEN_VOLENVDELAY);
fluid_clip(x, -12000.0f, 5000.0f);
count = NUM_FRAMES_DELAY(x);
volenv_data[FLUID_VOICE_ENVDELAY].count = count;
volenv_data[FLUID_VOICE_ENVDELAY].coeff = 0.0f;
volenv_data[FLUID_VOICE_ENVDELAY].incr = 0.0f;
volenv_data[FLUID_VOICE_ENVDELAY].min = -1.0f;
volenv_data[FLUID_VOICE_ENVDELAY].max = 1.0f;
break;
case GEN_VOLENVATTACK: /* SF2.01 section 8.1.3 # 34 */
x = GEN(GEN_VOLENVATTACK);
fluid_clip(x, -12000.0f, 8000.0f);
count = 1 + NUM_FRAMES_ATTACK(x);
volenv_data[FLUID_VOICE_ENVATTACK].count = count;
volenv_data[FLUID_VOICE_ENVATTACK].coeff = 1.0f;
volenv_data[FLUID_VOICE_ENVATTACK].incr = count ? 1.0f / count : 0.0f;
volenv_data[FLUID_VOICE_ENVATTACK].min = -1.0f;
volenv_data[FLUID_VOICE_ENVATTACK].max = 1.0f;
break;
case GEN_VOLENVHOLD: /* SF2.01 section 8.1.3 # 35 */
case GEN_KEYTOVOLENVHOLD: /* SF2.01 section 8.1.3 # 39 */
count = calculate_hold_decay_frames(GEN_VOLENVHOLD, GEN_KEYTOVOLENVHOLD, 0); /* 0 means: hold */
volenv_data[FLUID_VOICE_ENVHOLD].count = count;
volenv_data[FLUID_VOICE_ENVHOLD].coeff = 1.0f;
volenv_data[FLUID_VOICE_ENVHOLD].incr = 0.0f;
volenv_data[FLUID_VOICE_ENVHOLD].min = -1.0f;
volenv_data[FLUID_VOICE_ENVHOLD].max = 2.0f;
break;
case GEN_VOLENVDECAY: /* SF2.01 section 8.1.3 # 36 */
case GEN_VOLENVSUSTAIN: /* SF2.01 section 8.1.3 # 37 */
case GEN_KEYTOVOLENVDECAY: /* SF2.01 section 8.1.3 # 40 */
y = 1.0f - 0.001f * GEN(GEN_VOLENVSUSTAIN);
fluid_clip(y, 0.0f, 1.0f);
count = calculate_hold_decay_frames(GEN_VOLENVDECAY, GEN_KEYTOVOLENVDECAY, 1); /* 1 for decay */
volenv_data[FLUID_VOICE_ENVDECAY].count = count;
volenv_data[FLUID_VOICE_ENVDECAY].coeff = 1.0f;
volenv_data[FLUID_VOICE_ENVDECAY].incr = count ? -1.0f / count : 0.0f;
volenv_data[FLUID_VOICE_ENVDECAY].min = y;
volenv_data[FLUID_VOICE_ENVDECAY].max = 2.0f;
break;
case GEN_VOLENVRELEASE: /* SF2.01 section 8.1.3 # 38 */
x = GEN(GEN_VOLENVRELEASE);
fluid_clip(x, FLUID_MIN_VOLENVRELEASE, 8000.0f);
count = 1 + NUM_FRAMES_RELEASE(x);
volenv_data[FLUID_VOICE_ENVRELEASE].count = count;
volenv_data[FLUID_VOICE_ENVRELEASE].coeff = 1.0f;
volenv_data[FLUID_VOICE_ENVRELEASE].incr = count ? -1.0f / count : 0.0f;
volenv_data[FLUID_VOICE_ENVRELEASE].min = 0.0f;
volenv_data[FLUID_VOICE_ENVRELEASE].max = 1.0f;
break;
/* Modulation envelope */
case GEN_MODENVDELAY: /* SF2.01 section 8.1.3 # 25 */
x = GEN(GEN_MODENVDELAY);
fluid_clip(x, -12000.0f, 5000.0f);
modenv_data[FLUID_VOICE_ENVDELAY].count = NUM_FRAMES_DELAY(x);
modenv_data[FLUID_VOICE_ENVDELAY].coeff = 0.0f;
modenv_data[FLUID_VOICE_ENVDELAY].incr = 0.0f;
modenv_data[FLUID_VOICE_ENVDELAY].min = -1.0f;
modenv_data[FLUID_VOICE_ENVDELAY].max = 1.0f;
break;
case GEN_MODENVATTACK: /* SF2.01 section 8.1.3 # 26 */
x = GEN(GEN_MODENVATTACK);
fluid_clip(x, -12000.0f, 8000.0f);
count = 1 + NUM_FRAMES_ATTACK(x);
modenv_data[FLUID_VOICE_ENVATTACK].count = count;
modenv_data[FLUID_VOICE_ENVATTACK].coeff = 1.0f;
modenv_data[FLUID_VOICE_ENVATTACK].incr = count ? 1.0f / count : 0.0f;
modenv_data[FLUID_VOICE_ENVATTACK].min = -1.0f;
modenv_data[FLUID_VOICE_ENVATTACK].max = 1.0f;
break;
case GEN_MODENVHOLD: /* SF2.01 section 8.1.3 # 27 */
case GEN_KEYTOMODENVHOLD: /* SF2.01 section 8.1.3 # 31 */
count = calculate_hold_decay_frames(GEN_MODENVHOLD, GEN_KEYTOMODENVHOLD, 0); /* 1 means: hold */
modenv_data[FLUID_VOICE_ENVHOLD].count = count;
modenv_data[FLUID_VOICE_ENVHOLD].coeff = 1.0f;
modenv_data[FLUID_VOICE_ENVHOLD].incr = 0.0f;
modenv_data[FLUID_VOICE_ENVHOLD].min = -1.0f;
modenv_data[FLUID_VOICE_ENVHOLD].max = 2.0f;
break;
case GEN_MODENVDECAY: /* SF 2.01 section 8.1.3 # 28 */
case GEN_MODENVSUSTAIN: /* SF 2.01 section 8.1.3 # 29 */
case GEN_KEYTOMODENVDECAY: /* SF 2.01 section 8.1.3 # 32 */
count = calculate_hold_decay_frames(GEN_MODENVDECAY, GEN_KEYTOMODENVDECAY, 1); /* 1 for decay */
y = 1.0f - 0.001f * GEN(GEN_MODENVSUSTAIN);
fluid_clip(y, 0.0f, 1.0f);
modenv_data[FLUID_VOICE_ENVDECAY].count = count;
modenv_data[FLUID_VOICE_ENVDECAY].coeff = 1.0f;
modenv_data[FLUID_VOICE_ENVDECAY].incr = count ? -1.0f / count : 0.0f;
modenv_data[FLUID_VOICE_ENVDECAY].min = y;
modenv_data[FLUID_VOICE_ENVDECAY].max = 2.0f;
break;
case GEN_MODENVRELEASE: /* SF 2.01 section 8.1.3 # 30 */
x = GEN(GEN_MODENVRELEASE);
fluid_clip(x, -12000.0f, 8000.0f);
count = 1 + NUM_FRAMES_RELEASE(x);
modenv_data[FLUID_VOICE_ENVRELEASE].count = count;
modenv_data[FLUID_VOICE_ENVRELEASE].coeff = 1.0f;
modenv_data[FLUID_VOICE_ENVRELEASE].incr = count ? -1.0f / count : 0.0;
modenv_data[FLUID_VOICE_ENVRELEASE].min = 0.0f;
modenv_data[FLUID_VOICE_ENVRELEASE].max = 2.0f;
break;
} /* switch gen */
}
/**
* fluid_voice_modulate
*
* In this implementation, I want to make sure that all controllers
* are event based: the parameter values of the DSP algorithm should
* only be updates when a controller event arrived and not at every
* iteration of the audio cycle (which would probably be feasible if
* the synth was made in silicon).
*
* The update is done in three steps:
*
* - first, we look for all the modulators that have the changed
* controller as a source. This will yield a list of generators that
* will be changed because of the controller event.
*
* - For every changed generator, calculate its new value. This is the
* sum of its original value plus the values of al the attached
* modulators.
*
* - For every changed generator, convert its value to the correct
* unit of the corresponding DSP parameter
* */
void Voice::modulate(bool _cc, int _ctrl)
{
for (int i = 0; i < mod_count; i++) {
Mod* m = &mod[i];
/* step 1: find all the modulators that have the changed controller
* as input source.
*/
if (m->has_source(_cc, _ctrl)) {
int g = m->get_dest();
float modval = 0.0;
/* step 2: for every changed modulator, calculate the modulation
* value of its associated generator
*/
for (int k = 0; k < mod_count; k++) {
if (fluid_mod_has_dest(&mod[k], g)) {
modval += mod[k].get_value(channel, this);
}
}
gen[g].set_mod(modval);
/* step 3: now that we have the new value of the generator,
* recalculate the parameter values that are derived from the
* generator
*/
update_param(g);
}
}
}
/**
* fluid_voice_modulate_all
*
* Update all the modulators. This function is called after a
* ALL_CTRL_OFF MIDI message has been received (CC 121).
*
*/
void Voice::modulate_all()
{
/* Loop through all the modulators.
FIXME: we should loop through the set of generators instead of
the set of modulators. We risk to call 'fluid_voice_update_param'
several times for the same generator if several modulators have
that generator as destination. It's not an error, just a wast of
energy (think pollution, global warming, unhappy musicians, ...)
*/
for (int i = 0; i < mod_count; i++) {
Mod* m = &mod[i];
int g = m->get_dest();
float modval = 0.0;
/* Accumulate the modulation values of all the modulators with
* destination generator 'gen'
*/
for (int k = 0; k < mod_count; k++) {
if (fluid_mod_has_dest(&mod[k], g))
modval += mod[k].get_value(channel, this);
}
gen[g].set_mod(modval);
/* Update the parameter values that are depend on the generator
* 'gen'
*/
update_param(g);
}
}
/*
* fluid_voice_noteoff
*/
void Voice::noteoff()
{
if (channel && channel->sustained())
status = FLUID_VOICE_SUSTAINED;
else {
if (volenv_section == FLUID_VOICE_ENVATTACK) {
/* A voice is turned off during the attack section of the volume
* envelope. The attack section ramps up linearly with
* amplitude. The other sections use logarithmic scaling. Calculate new
* volenv_val to achieve equievalent amplitude during the release phase
* for seamless volume transition.
*/
if (volenv_val > 0) {
float lfo = modlfo_val * -modlfo_to_vol;
float amp = volenv_val * pow (10.0, lfo / -200);
float env_value = - ((-200 * log (amp) / log (10.0) - lfo) / 960.0 - 1);
fluid_clip (env_value, 0.0, 1.0);
volenv_val = env_value;
}
}
volenv_section = FLUID_VOICE_ENVRELEASE;
volenv_count = 0;
modenv_section = FLUID_VOICE_ENVRELEASE;
modenv_count = 0;
}
}
/*
* fluid_voice_kill_excl
*
* Percussion sounds can be mutually exclusive: for example, a 'closed
* hihat' sound will terminate an 'open hihat' sound ringing at the
* same time. This behaviour is modeled using 'exclusive classes',
* turning on a voice with an exclusive class other than 0 will kill
* all other voices having that exclusive class within the same preset
* or channel. fluid_voice_kill_excl gets called, when 'voice' is to
* be killed for that reason.
*/
void Voice::kill_excl()
{
if (!isPlaying())
return;
/* Turn off the exclusive class information for this voice,
so that it doesn't get killed twice
*/
gen_set(GEN_EXCLUSIVECLASS, 0);
/* If the voice is not yet in release state, put it into release state */
if (volenv_section != FLUID_VOICE_ENVRELEASE) {
volenv_section = FLUID_VOICE_ENVRELEASE;
volenv_count = 0;
modenv_section = FLUID_VOICE_ENVRELEASE;
modenv_count = 0;
}
/* Speed up the volume envelope */
/* The value was found through listening tests with hi-hat samples. */
gen_set(GEN_VOLENVRELEASE, -200);
update_param(GEN_VOLENVRELEASE);
/* Speed up the modulation envelope */
gen_set(GEN_MODENVRELEASE, -200);
update_param(GEN_MODENVRELEASE);
}
//---------------------------------------------------------
// off
// Turns off a voice, meaning that it is not processed
// anymore by the DSP loop.
//---------------------------------------------------------
void Voice::off()
{
chan = NO_CHANNEL;
volenv_section = FLUID_VOICE_ENVFINISHED;
volenv_count = 0;
modenv_section = FLUID_VOICE_ENVFINISHED;
modenv_count = 0;
status = FLUID_VOICE_OFF;
_fluid->freeVoice(this);
_cachedFrames = 0;
_initialCacheFrames = 0;
}
/*
* fluid_voice_add_mod
*
* Adds a modulator to the voice. "mode" indicates, what to do, if
* an identical modulator exists already.
*
* mode == FLUID_VOICE_ADD: Identical modulators on preset level are added
* mode == FLUID_VOICE_OVERWRITE: Identical modulators on instrument level are overwritten
* mode == FLUID_VOICE_DEFAULT: This is a default modulator, there can be no identical modulator.
* Don't check.
*/
void Voice::add_mod(const Mod* _mod, int mode)
{
/*
* Some soundfonts come with a huge number of non-standard
* controllers, because they have been designed for one particular
* sound card. Discard them, maybe print a warning.
*/
if (((_mod->flags1 & FLUID_MOD_CC) == 0)
&& ((_mod->src1 != 0) /* SF2.01 section 8.2.1: Constant value */
&& (_mod->src1 != 2) /* Note-on velocity */
&& (_mod->src1 != 3) /* Note-on key number */
&& (_mod->src1 != 10) /* Poly pressure */
&& (_mod->src1 != 13) /* Channel pressure */
&& (_mod->src1 != 14) /* Pitch wheel */
&& (_mod->src1 != 16))) { /* Pitch wheel sensitivity */
qDebug("Ignoring invalid controller, using non-CC source %i.", _mod->src1);
return;
}
if (mode == FLUID_VOICE_ADD) {
/* if identical modulator exists, add them */
for (int i = 0; i < mod_count; i++) {
if (test_identity(&mod[i], _mod)) {
// printf("Adding modulator...\n");
mod[i].amount += _mod->amount;
return;
}
}
}
else if (mode == FLUID_VOICE_OVERWRITE) {
/* if identical modulator exists, replace it (only the amount has to be changed) */
for (int i = 0; i < mod_count; i++) {
if (test_identity(&mod[i], _mod)) {
// printf("Replacing modulator...amount is %f\n",mod->amount);
mod[i].amount = _mod->amount;
return;
}
}
}
/* Add a new modulator (No existing modulator to add / overwrite).
Also, default modulators (FLUID_VOICE_DEFAULT) are added without
checking, if the same modulator already exists.
*/
if (mod_count < FLUID_NUM_MOD)
_mod->clone(&mod[mod_count++]);
}
/*
* fluid_voice_get_lower_boundary_for_attenuation
*
* Purpose:
*
* A lower boundary for the attenuation (as in 'the minimum
* attenuation of this voice, with volume pedals, modulators
* etc. resulting in minimum attenuation, cannot fall below x cB) is
* calculated. This has to be called during fluid_voice_init, after
* all modulators have been run on the voice once. Also,
* voice->attenuation has to be initialized.
*/
float Voice::get_lower_boundary_for_attenuation()
{
float possible_att_reduction_cB = 0;
for (int i = 0; i < mod_count; i++) {
Mod* m = &mod[i];
/* Modulator has attenuation as target and can change over time? */
if ((m->dest == GEN_ATTENUATION) && ((m->flags1 & FLUID_MOD_CC) || (m->flags2 & FLUID_MOD_CC))) {
float current_val = m->get_value(channel, this);
float v = fabs(m->amount);
if ((m->src1 == FLUID_MOD_PITCHWHEEL)
|| (m->flags1 & FLUID_MOD_BIPOLAR)
|| (m->flags2 & FLUID_MOD_BIPOLAR)
|| (m->amount < 0)) {
/* Can this modulator produce a negative contribution? */
v *= -1.0;
}
else {
/* No negative value possible. But still, the minimum contribution is 0. */
v = 0;
}
/* For example:
* - current_val=100
* - min_val=-4000
* - possible_att_reduction_cB += 4100
*/
if (current_val > v)
possible_att_reduction_cB += (current_val - v);
}
}
float lower_bound = attenuation - possible_att_reduction_cB;
/* SF2.01 specs do not allow negative attenuation */
if (lower_bound < 0)
lower_bound = 0;
return lower_bound;
}
/* Purpose:
*
* Make sure, that sample start / end point and loop points are in
* proper order. When starting up, calculate the initial phase.
*/
void Voice::check_sample_sanity()
{
int min_index_nonloop=(int) sample->start;
int max_index_nonloop=(int) sample->end;
/* make sure we have enough samples surrounding the loop */
int min_index_loop=(int) sample->start + FLUID_MIN_LOOP_PAD;
int max_index_loop=(int) sample->end - FLUID_MIN_LOOP_PAD;
fluid_check_fpe("voice_check_sample_sanity start");
if (!check_sample_sanity_flag)
return;
#if 0
printf("Sample from %i to %i\n", sample->start, sample->end);
printf("Sample loop from %i %i\n", sample->loopstart, sample->loopend);
printf("Playback from %i to %i\n", start, end);
printf("Playback loop from %i to %i\n", loopstart, loopend);
#endif
/* Keep the start point within the sample data */
if (start < min_index_nonloop)
start = min_index_nonloop;
else if (start > max_index_nonloop)
start = max_index_nonloop;
/* Keep the end point within the sample data */
if (end < min_index_nonloop)
end = min_index_nonloop;
else if (end > max_index_nonloop)
end = max_index_nonloop;
/* Keep start and end point in the right order */
if (start > end) {
int temp = start;
start = end;
end = temp;
}
/* Zero length? */
if (start == end) {
off();
return;
}
if ((SAMPLEMODE() == FLUID_LOOP_UNTIL_RELEASE) || (SAMPLEMODE() == FLUID_LOOP_DURING_RELEASE)) {
/* Keep the loop start point within the sample data */
if (loopstart < min_index_loop)
loopstart = min_index_loop;
else if (loopstart > max_index_loop)
loopstart = max_index_loop;
/* Keep the loop end point within the sample data */
if (loopend < min_index_loop)
loopend = min_index_loop;
else if (loopend > max_index_loop)
loopend = max_index_loop;
/* Keep loop start and end point in the right order */
if (loopstart > loopend){
int temp = loopstart;
loopstart = loopend;
loopend = temp;
}
/* Loop too short? Then don't loop. */
if (loopend < loopstart + FLUID_MIN_LOOP_SIZE)
gen[GEN_SAMPLEMODE].val = FLUID_UNLOOPED;
/* The loop points may have changed. Obtain a new estimate for the loop volume. */
/* Is the voice loop within the sample loop?
*/
if ((int)loopstart >= (int)sample->loopstart && (int)loopend <= (int)sample->loopend){
/* Is there a valid peak amplitude available for the loop? */
if (sample->amplitude_that_reaches_noise_floor_is_valid) {
amplitude_that_reaches_noise_floor_loop = sample->amplitude_that_reaches_noise_floor;
}
else
/* Worst case */
amplitude_that_reaches_noise_floor_loop = amplitude_that_reaches_noise_floor_nonloop;
}
} /* if sample mode is looped */
/* Run startup specific code (only once, when the voice is started) */
if (check_sample_sanity_flag & FLUID_SAMPLESANITY_STARTUP) {
if (max_index_loop - min_index_loop < FLUID_MIN_LOOP_SIZE){
if ((SAMPLEMODE() == FLUID_LOOP_UNTIL_RELEASE) || (SAMPLEMODE() == FLUID_LOOP_DURING_RELEASE))
gen[GEN_SAMPLEMODE].val = FLUID_UNLOOPED;
}
/* Set the initial phase of the voice (using the result from the
start offset modulators).
*/
phase.setInt(start);
} /* if startup */
/* Is this voice run in loop mode, or does it run straight to the
end of the waveform data?
*/
if (((SAMPLEMODE() == FLUID_LOOP_UNTIL_RELEASE) && (volenv_section < FLUID_VOICE_ENVRELEASE)) || (SAMPLEMODE() == FLUID_LOOP_DURING_RELEASE)) {
/* Yes, it will loop as soon as it reaches the loop point. In
* this case we must prevent, that the playback pointer (phase)
* happens to end up beyond the 2nd loop point, because the
* point has moved. The DSP algorithm is unable to cope with
* that situation. So if the phase is beyond the 2nd loop
* point, set it to the start of the loop. No way to avoid some
* noise here. Note: If the sample pointer ends up -before the
* first loop point- instead, then the DSP loop will just play
* the sample, enter the loop and proceed as expected => no
* actions required.
*/
int index_in_sample = phase.index();
if (index_in_sample >= loopend) {
/* FLUID_LOG(FLUID_DBG, "Loop / sample sanity check: Phase after 2nd loop point!"); */
phase.setInt(loopstart);
}
}
/* FLUID_LOG(FLUID_DBG, "Loop / sample sanity check: Sample from %i to %i, loop from %i to %i", voice->start, voice->end, voice->loopstart, voice->loopend); */
/* Sample sanity has been assured. Don't check again, until some
sample parameter is changed by modulation.
*/
check_sample_sanity_flag = 0;
fluid_check_fpe("voice_check_sample_sanity");
}
//---------------------------------------------------------
// set_param
//---------------------------------------------------------
void Voice::set_param(int g, float nrpn_value, int abs)
{
gen[g].nrpn = nrpn_value;
gen[g].flags = (abs)? GEN_ABS_NRPN : GEN_SET;
update_param(g);
}
/** If the peak volume during the loop is known, then the voice can
* be released earlier during the release phase. Otherwise, the
* voice will operate (inaudibly), until the envelope is at the
* nominal turnoff point. In many cases the loop volume is many dB
* below the maximum volume. For example, the loop volume for a
* typical acoustic piano is 20 dB below max. Taking that into
* account in the turn-off algorithm we can save 20 dB / 100 dB =>
* 1/5 of the total release time.
* So it's a good idea to call fluid_voice_optimize_sample
* on each sample once.
*/
/* - Scan the loop
* - determine the peak level
* - Calculate, what factor will make the loop inaudible
* - Store in sample
*/
void Sample::optimize()
{
Sample* s = this;
signed short peak_max = 0;
signed short peak_min = 0;
signed short peak;
float normalized_amplitude_during_loop;
double result;
int i;
/* ignore ROM and other(?) invalid samples */
if (!s->valid())
return;
if (!s->amplitude_that_reaches_noise_floor_is_valid) { /* Only once */
/* Scan the loop */
for (i = (int)s->loopstart; i < (int) s->loopend; i ++) {
signed short val = s->data[i];
if (val > peak_max)
peak_max = val;
else if (val < peak_min)
peak_min = val;
}
/* Determine the peak level */
if (peak_max > -peak_min)
peak = peak_max;
else
peak = -peak_min;
if (peak == 0) /* Avoid division by zero */
peak = 1;
/* Calculate what factor will make the loop inaudible
* For example: Take a peak of 3277 (10 % of 32768). The
* normalized amplitude is 0.1 (10 % of 32768). An amplitude
* factor of 0.0001 (as opposed to the default 0.00001) will
* drop this sample to the noise floor.
*/
/* 16 bits => 96+4=100 dB dynamic range => 0.00001 */
normalized_amplitude_during_loop = ((float)peak)/32768.;
result = FLUID_NOISE_FLOOR / normalized_amplitude_during_loop;
/* Store in sample */
s->amplitude_that_reaches_noise_floor = (double)result;
s->amplitude_that_reaches_noise_floor_is_valid = 1;
}
}
/* Purpose:
*
* - filters (applies a lowpass filter with variable cutoff frequency and quality factor)
* - mixes the processed sample to left and right output using the pan setting
* - sends the processed sample to chorus and reverb
*
* A couple of variables are used internally, their results are discarded:
* - dsp_phase_fractional: The fractional part of dsp_phase
* - dsp_coeff: A table of four coefficients, depending on the fractional phase.
* Used to interpolate between samples.
* - dsp_process_buffer: Holds the processed signal between stages
* - dsp_centernode: delay line for the IIR filter
* - dsp_hist1: same
* - dsp_hist2: same
*
*/
void Voice::effects(int startBufIdx, int count, float* out, float* reverb, float* chorus)
{
/* filter (implement the voice filter according to SoundFont standard) */
/* Check for denormal number (too close to zero). */
if (fabs (hist1) < 1e-20)
hist1 = 0.0f; /* FIXME JMG - Is this even needed? */
/* Two versions of the filter loop. One, while the filter is
* changing towards its new setting. The other, if the filter
* doesn't change.
*/
if (filter_coeff_incr_count > 0) {
/* Increment is added to each filter coefficient filter_coeff_incr_count times. */
for (int i = startBufIdx; i < startBufIdx + count; i++) {
/* The filter is implemented in Direct-II form. */
float dsp_centernode = dsp_buf[i] - a1 * hist1 - a2 * hist2;
dsp_buf[i] = b02 * (dsp_centernode + hist2) + b1 * hist1;
hist2 = hist1;
hist1 = dsp_centernode;
if (filter_coeff_incr_count-- > 0) {
a1 += a1_incr;
a2 += a2_incr;
b02 += b02_incr;
b1 += b1_incr;
}
}
}
else { /* The filter parameters are constant. This is duplicated to save time. */
for (int i = startBufIdx; i < startBufIdx + count; i++) { // The filter is implemented in Direct-II form.
float dsp_centernode = dsp_buf[i] - a1 * hist1 - a2 * hist2;
dsp_buf[i] = b02 * (dsp_centernode + hist2) + b1 * hist1;
hist2 = hist1;
hist1 = dsp_centernode;
}
}
for (int i = startBufIdx; i < startBufIdx + count; ++i) {
float v = dsp_buf[i];
float vv = v * amp_left;
*out++ += vv;
*reverb++ += vv * amp_reverb;
*chorus++ += vv * amp_chorus;
vv = v * amp_right;
*out++ += vv;
*reverb++ += vv * amp_reverb;
*chorus++ += vv * amp_chorus;
}
}
}