ref: 54f35b1aa6be6f13704bdcedbe590fd0f12eb3cf
dir: /LEAF/Src/leaf-utilities.c/
/*
==============================================================================
LEAFUtilities.c
Created: 20 Jan 2017 12:02:17pm
Author: Michael R Mulshine
==============================================================================
*/
#if _WIN32 || _WIN64
#include "..\Inc\leaf-utilities.h"
#include "..\Inc\leaf-wavetables.h"
#include "..\leaf.h"
#include "..\Inc\d_fft_mayer.h"
#else
#include "../Inc/leaf-utilities.h"
#include "../Inc/leaf-wavetables.h"
#include "../leaf.h"
#include "../Externals/d_fft_mayer.h"
#endif
#define LOGTEN 2.302585092994
float mtof(float f)
{
if (f <= -1500.0f) return(0);
else if (f > 1499.0f) return(mtof(1499.0f));
else return (8.17579891564f * exp(0.0577622650f * f));
}
float ftom(float f)
{
return (f > 0 ? 17.3123405046f * log(.12231220585f * f) : -1500.0f);
}
float powtodb(float f)
{
if (f <= 0) return (0);
else
{
float val = 100 + 10.f/LOGTEN * log(f);
return (val < 0 ? 0 : val);
}
}
float rmstodb(float f)
{
if (f <= 0) return (0);
else
{
float val = 100 + 20.f/LOGTEN * log(f);
return (val < 0 ? 0 : val);
}
}
float dbtopow(float f)
{
if (f <= 0)
return(0);
else
{
if (f > 870.0f)
f = 870.0f;
return (exp((LOGTEN * 0.1f) * (f-100.0f)));
}
}
float dbtorms(float f)
{
if (f <= 0)
return(0);
else
{
if (f > 485.0f)
f = 485.0f;
}
return (exp((LOGTEN * 0.05f) * (f-100.0f)));
}
/* ---------------- env~ - simple envelope follower. ----------------- */
void tEnv_init(tEnv* const x, int ws, int hs, int bs)
{
int period = hs, npoints = ws;
int i;
if (npoints < 1) npoints = 1024;
if (period < 1) period = npoints/2;
if (period < npoints / MAXOVERLAP + 1)
period = npoints / MAXOVERLAP + 1;
x->x_npoints = npoints;
x->x_phase = 0;
x->x_period = period;
x->windowSize = npoints;
x->hopSize = period;
x->blockSize = bs;
for (i = 0; i < MAXOVERLAP; i++) x->x_sumbuf[i] = 0;
for (i = 0; i < npoints; i++)
x->buf[i] = (1.0f - cos((2 * PI * i) / npoints))/npoints;
for (; i < npoints+INITVSTAKEN; i++) x->buf[i] = 0;
x->x_f = 0;
x->x_allocforvs = INITVSTAKEN;
// ~ ~ ~ dsp ~ ~ ~
if (x->x_period % x->blockSize)
{
x->x_realperiod = x->x_period + x->blockSize - (x->x_period % x->blockSize);
}
else
{
x->x_realperiod = x->x_period;
}
// ~ ~ ~ ~ ~ ~ ~ ~
}
void tEnv_free (tEnv* const x)
{
leaf_free(x);
}
float tEnv_tick (tEnv* const x)
{
return powtodb(x->x_result);
}
void tEnv_processBlock(tEnv* const x, float* in)
{
int n = x->blockSize;
int count;
t_sample *sump;
in += n;
for (count = x->x_phase, sump = x->x_sumbuf;
count < x->x_npoints; count += x->x_realperiod, sump++)
{
t_sample *hp = x->buf + count;
t_sample *fp = in;
t_sample sum = *sump;
int i;
for (i = 0; i < n; i++)
{
fp--;
sum += *hp++ * (*fp * *fp);
}
*sump = sum;
}
sump[0] = 0;
x->x_phase -= n;
if (x->x_phase < 0)
{
x->x_result = x->x_sumbuf[0];
for (count = x->x_realperiod, sump = x->x_sumbuf;
count < x->x_npoints; count += x->x_realperiod, sump++)
sump[0] = sump[1];
sump[0] = 0;
x->x_phase = x->x_realperiod - n;
}
}
// ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ Compressor ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ //
/*
tCompressor* tCompressorInit(int tauAttack, int tauRelease)
{
tCompressor* c = &leaf.tCompressorRegistry[leaf.registryIndex[T_COMPRESSOR]++];
c->tauAttack = tauAttack;
c->tauRelease = tauRelease;
c->x_G[0] = 0.0f, c->x_G[1] = 0.0f,
c->y_G[0] = 0.0f, c->y_G[1] = 0.0f,
c->x_T[0] = 0.0f, c->x_T[1] = 0.0f,
c->y_T[0] = 0.0f, c->y_T[1] = 0.0f;
c->T = 0.0f; // Threshold
c->R = 1.0f; // compression Ratio
c->M = 0.0f; // decibel Make-up gain
c->W = 0.0f; // decibel Width of knee transition
return c;
}
*/
void tCompressor_init(tCompressor* const c)
{
c->tauAttack = 100;
c->tauRelease = 100;
c->isActive = OFALSE;
c->T = 0.0f; // Threshold
c->R = 0.5f; // compression Ratio
c->M = 3.0f; // decibel Width of knee transition
c->W = 1.0f; // decibel Make-up gain
}
int ccount = 0;
float tCompressor_tick(tCompressor* const c, float in)
{
float slope, overshoot;
float alphaAtt, alphaRel;
float in_db = 20.0f * log10f( fmaxf( fabsf( in), 0.000001f)), out_db = 0.0f;
c->y_T[1] = c->y_T[0];
slope = c->R - 1.0f; // feed-forward topology; was 1/C->R - 1
overshoot = in_db - c->T;
if (overshoot <= -(c->W * 0.5f))
{
out_db = in_db;
c->isActive = OFALSE;
}
else if ((overshoot > -(c->W * 0.5f)) && (overshoot < (c->W * 0.5f)))
{
out_db = in_db + slope * (powf((overshoot + c->W*0.5f),2) / (2.0f * c->W)); // .^ 2 ???
c->isActive = OTRUE;
}
else if (overshoot >= (c->W * 0.5f))
{
out_db = in_db + slope * overshoot;
c->isActive = OTRUE;
}
c->x_T[0] = out_db - in_db;
alphaAtt = expf(-1.0f/(0.001f * c->tauAttack * leaf.sampleRate));
alphaRel = expf(-1.0f/(0.001f * c->tauRelease * leaf.sampleRate));
if (c->x_T[0] > c->y_T[1])
c->y_T[0] = alphaAtt * c->y_T[1] + (1-alphaAtt) * c->x_T[0];
else
c->y_T[0] = alphaRel * c->y_T[1] + (1-alphaRel) * c->x_T[0];
float attenuation = powf(10.0f, ((c->M - c->y_T[0])/20.0f));
/*
if (++ccount > 5000)
{
ccount = 0;
DBG(".5width: " + String(c->W * 0.5f));
DBG("slope: " + String(slope) + " overshoot: " + String(overshoot));
DBG("attenuation: " + String(attenuation));
}
*/
return attenuation * in;
}
// ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ Envelope ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ //
void tEnvelope_init(tEnvelope* const env, float attack, float decay, oBool loop)
{
env->exp_buff = exp_decay;
env->inc_buff = attack_decay_inc;
env->buff_size = sizeof(exp_decay);
env->loop = loop;
if (attack > 8192.0f)
attack = 8192.0f;
if (attack < 0.0f)
attack = 0.0f;
if (decay > 8192.0f)
decay = 8192.0f;
if (decay < 0.0f)
decay = 0.0f;
int16_t attackIndex = ((int16_t)(attack * 8.0f))-1;
int16_t decayIndex = ((int16_t)(decay * 8.0f))-1;
int16_t rampIndex = ((int16_t)(2.0f * 8.0f))-1;
if (attackIndex < 0)
attackIndex = 0;
if (decayIndex < 0)
decayIndex = 0;
if (rampIndex < 0)
rampIndex = 0;
env->inRamp = OFALSE;
env->inAttack = OFALSE;
env->inDecay = OFALSE;
env->attackInc = env->inc_buff[attackIndex];
env->decayInc = env->inc_buff[decayIndex];
env->rampInc = env->inc_buff[rampIndex];
}
void tEnvelope_free(tEnvelope* const env)
{
leaf_free(env);
}
int tEnvelope_setAttack(tEnvelope* const env, float attack)
{
int32_t attackIndex;
if (attack < 0.0f) {
attackIndex = 0.0f;
} else if (attack < 8192.0f) {
attackIndex = ((int32_t)(attack * 8.0f))-1;
} else {
attackIndex = ((int32_t)(8192.0f * 8.0f))-1;
}
env->attackInc = env->inc_buff[attackIndex];
return 0;
}
int tEnvelope_setDecay(tEnvelope* const env, float decay)
{
int32_t decayIndex;
if (decay < 0.0f) {
decayIndex = 0.0f;
} else if (decay < 8192.0f) {
decayIndex = ((int32_t)(decay * 8.0f)) - 1;
} else {
decayIndex = ((int32_t)(8192.0f * 8.0f)) - 1;
}
env->decayInc = env->inc_buff[decayIndex];
return 0;
}
int tEnvelope_loop(tEnvelope* const env, oBool loop)
{
env->loop = loop;
return 0;
}
int tEnvelope_on(tEnvelope* const env, float velocity)
{
if (env->inAttack || env->inDecay) // In case envelope retriggered while it is still happening.
{
env->rampPhase = 0;
env->inRamp = OTRUE;
env->rampPeak = env->next;
}
else // Normal start.
{
env->inAttack = OTRUE;
}
env->attackPhase = 0;
env->decayPhase = 0;
env->inDecay = OFALSE;
env->gain = velocity;
return 0;
}
float tEnvelope_tick(tEnvelope* const env)
{
if (env->inRamp)
{
if (env->rampPhase > UINT16_MAX)
{
env->inRamp = OFALSE;
env->inAttack = OTRUE;
env->next = 0.0f;
}
else
{
env->next = env->rampPeak * env->exp_buff[(uint32_t)env->rampPhase];
}
env->rampPhase += env->rampInc;
}
if (env->inAttack)
{
// If attack done, time to turn around.
if (env->attackPhase > UINT16_MAX)
{
env->inDecay = OTRUE;
env->inAttack = OFALSE;
env->next = env->gain * 1.0f;
}
else
{
// do interpolation !
env->next = env->gain * env->exp_buff[UINT16_MAX - (uint32_t)env->attackPhase]; // inverted and backwards to get proper rising exponential shape/perception
}
// Increment envelope attack.
env->attackPhase += env->attackInc;
}
if (env->inDecay)
{
// If decay done, finish.
if (env->decayPhase >= UINT16_MAX)
{
env->inDecay = OFALSE;
if (env->loop)
{
env->attackPhase = 0;
env->decayPhase = 0;
env->inAttack = OTRUE;
}
else
{
env->next = 0.0f;
}
} else {
env->next = env->gain * (env->exp_buff[(uint32_t)env->decayPhase]); // do interpolation !
}
// Increment envelope decay;
env->decayPhase += env->decayInc;
}
return env->next;
}
/* ADSR */
void tADSR_init(tADSR* const adsr, float attack, float decay, float sustain, float release)
{
adsr->exp_buff = exp_decay;
adsr->inc_buff = attack_decay_inc;
adsr->buff_size = sizeof(exp_decay);
if (attack > 8192.0f)
attack = 8192.0f;
if (attack < 0.0f)
attack = 0.0f;
if (decay > 8192.0f)
decay = 8192.0f;
if (decay < 0.0f)
decay = 0.0f;
if (sustain > 1.0f)
sustain = 1.0f;
if (sustain < 0.0f)
sustain = 0.0f;
if (release > 8192.0f)
release = 8192.0f;
if (release < 0.0f)
release = 0.0f;
int16_t attackIndex = ((int16_t)(attack * 8.0f))-1;
int16_t decayIndex = ((int16_t)(decay * 8.0f))-1;
int16_t releaseIndex = ((int16_t)(release * 8.0f))-1;
int16_t rampIndex = ((int16_t)(2.0f * 8.0f))-1;
if (attackIndex < 0)
attackIndex = 0;
if (decayIndex < 0)
decayIndex = 0;
if (releaseIndex < 0)
releaseIndex = 0;
if (rampIndex < 0)
rampIndex = 0;
adsr->inRamp = OFALSE;
adsr->inAttack = OFALSE;
adsr->inDecay = OFALSE;
adsr->inSustain = OFALSE;
adsr->inRelease = OFALSE;
adsr->sustain = sustain;
adsr->attackInc = adsr->inc_buff[attackIndex];
adsr->decayInc = adsr->inc_buff[decayIndex];
adsr->releaseInc = adsr->inc_buff[releaseIndex];
adsr->rampInc = adsr->inc_buff[rampIndex];
}
int tADSR_setAttack(tADSR* const adsr, float attack)
{
int32_t attackIndex;
if (attack < 0.0f) {
attackIndex = 0.0f;
} else if (attack < 8192.0f) {
attackIndex = ((int32_t)(attack * 8.0f))-1;
} else {
attackIndex = ((int32_t)(8192.0f * 8.0f))-1;
}
adsr->attackInc = adsr->inc_buff[attackIndex];
return 0;
}
int tADSR_detDecay(tADSR* const adsr, float decay)
{
int32_t decayIndex;
if (decay < 0.0f) {
decayIndex = 0.0f;
} else if (decay < 8192.0f) {
decayIndex = ((int32_t)(decay * 8.0f)) - 1;
} else {
decayIndex = ((int32_t)(8192.0f * 8.0f)) - 1;
}
adsr->decayInc = adsr->inc_buff[decayIndex];
return 0;
}
int tADSR_setSustain(tADSR *const adsr, float sustain)
{
if (sustain > 1.0f) adsr->sustain = 1.0f;
else if (sustain < 0.0f) adsr->sustain = 0.0f;
else adsr->sustain = sustain;
return 0;
}
int tADSR_setRelease(tADSR* const adsr, float release)
{
int32_t releaseIndex;
if (release < 0.0f) {
releaseIndex = 0.0f;
} else if (release < 8192.0f) {
releaseIndex = ((int32_t)(release * 8.0f)) - 1;
} else {
releaseIndex = ((int32_t)(8192.0f * 8.0f)) - 1;
}
adsr->releaseInc = adsr->inc_buff[releaseIndex];
return 0;
}
int tADSR_on(tADSR* const adsr, float velocity)
{
if ((adsr->inAttack || adsr->inDecay) || (adsr->inSustain || adsr->inRelease)) // In case ADSR retriggered while it is still happening.
{
adsr->rampPhase = 0;
adsr->inRamp = OTRUE;
adsr->rampPeak = adsr->next;
}
else // Normal start.
{
adsr->inAttack = OTRUE;
}
adsr->attackPhase = 0;
adsr->decayPhase = 0;
adsr->releasePhase = 0;
adsr->inDecay = OFALSE;
adsr->inSustain = OFALSE;
adsr->inRelease = OFALSE;
adsr->gain = velocity;
return 0;
}
int tADSR_off(tADSR* const adsr)
{
if (adsr->inRelease) return 0;
adsr->inAttack = OFALSE;
adsr->inDecay = OFALSE;
adsr->inSustain = OFALSE;
adsr->inRelease = OTRUE;
adsr->releasePeak = adsr->next;
return 0;
}
float tADSR_tick(tADSR* const adsr)
{
if (adsr->inRamp)
{
if (adsr->rampPhase > UINT16_MAX)
{
adsr->inRamp = OFALSE;
adsr->inAttack = OTRUE;
adsr->next = 0.0f;
}
else
{
adsr->next = adsr->rampPeak * adsr->exp_buff[(uint32_t)adsr->rampPhase];
}
adsr->rampPhase += adsr->rampInc;
}
if (adsr->inAttack)
{
// If attack done, time to turn around.
if (adsr->attackPhase > UINT16_MAX)
{
adsr->inDecay = OTRUE;
adsr->inAttack = OFALSE;
adsr->next = adsr->gain * 1.0f;
}
else
{
// do interpolation !
adsr->next = adsr->gain * adsr->exp_buff[UINT16_MAX - (uint32_t)adsr->attackPhase]; // inverted and backwards to get proper rising exponential shape/perception
}
// Increment ADSR attack.
adsr->attackPhase += adsr->attackInc;
}
if (adsr->inDecay)
{
// If decay done, sustain.
if (adsr->decayPhase >= UINT16_MAX)
{
adsr->inDecay = OFALSE;
adsr->inSustain = OTRUE;
adsr->next = adsr->gain * adsr->sustain;
}
else
{
adsr->next = adsr->gain * (adsr->sustain + ((adsr->exp_buff[(uint32_t)adsr->decayPhase]) * (1 - adsr->sustain))); // do interpolation !
}
// Increment ADSR decay.
adsr->decayPhase += adsr->decayInc;
}
if (adsr->inRelease)
{
// If release done, finish.
if (adsr->releasePhase >= UINT16_MAX)
{
adsr->inRelease = OFALSE;
adsr->next = 0.0f;
}
else {
adsr->next = adsr->releasePeak * (adsr->exp_buff[(uint32_t)adsr->releasePhase]); // do interpolation !
}
// Increment envelope release;
adsr->releasePhase += adsr->releaseInc;
}
return adsr->next;
}
/* Envelope Follower */
void tEnvelopeFollower_init(tEnvelopeFollower* const e, float attackThreshold, float decayCoeff)
{
e->y = 0.0f;
e->a_thresh = attackThreshold;
e->d_coeff = decayCoeff;
}
float tEnvelopeFollower_tick(tEnvelopeFollower* const ef, float x)
{
if (x < 0.0f ) x = -x; /* Absolute value. */
if ((x >= ef->y) && (x > ef->a_thresh)) ef->y = x; /* If we hit a peak, ride the peak to the top. */
else ef->y = ef->y * ef->d_coeff; /* Else, exponential decay of output. */
//ef->y = envelope_pow[(uint16_t)(ef->y * (float)UINT16_MAX)] * ef->d_coeff; //not quite the right behavior - too much loss of precision?
//ef->y = powf(ef->y, 1.000009f) * ef->d_coeff; // too expensive
if( ef->y < VSF) ef->y = 0.0f;
return ef->y;
}
int tEnvelopeFollower_decayCoeff(tEnvelopeFollower* const ef, float decayCoeff)
{
return ef->d_coeff = decayCoeff;
}
int tEnvelopeFollower_attackThresh(tEnvelopeFollower* const ef, float attackThresh)
{
return ef->a_thresh = attackThresh;
}
/* Ramp */
void tRamp_init(tRamp* const ramp, float time, int samples_per_tick)
{
ramp->inv_sr_ms = 1.0f/(leaf.sampleRate*0.001f);
ramp->minimum_time = ramp->inv_sr_ms * samples_per_tick;
ramp->curr = 0.0f;
ramp->dest = 0.0f;
if (time < ramp->minimum_time)
{
ramp->time = ramp->minimum_time;
}
else
{
ramp->time = time;
}
ramp->samples_per_tick = samples_per_tick;
ramp->inc = ((ramp->dest - ramp->curr) / ramp->time * ramp->inv_sr_ms) * (float)ramp->samples_per_tick;
}
int tRamp_setTime(tRamp* const r, float time)
{
if (time < r->minimum_time)
{
r->time = r->minimum_time;
}
else
{
r->time = time;
}
r->inc = ((r->dest-r->curr)/r->time * r->inv_sr_ms) * ((float)r->samples_per_tick);
return 0;
}
int tRamp_setDest(tRamp* const r, float dest)
{
r->dest = dest;
r->inc = ((r->dest-r->curr)/r->time * r->inv_sr_ms) * ((float)r->samples_per_tick);
return 0;
}
int tRamp_setVal(tRamp* const r, float val)
{
r->curr = val;
r->inc = ((r->dest-r->curr)/r->time * r->inv_sr_ms) * ((float)r->samples_per_tick);
return 0;
}
float tRamp_tick(tRamp* const r) {
r->curr += r->inc;
if (((r->curr >= r->dest) && (r->inc > 0.0f)) || ((r->curr <= r->dest) && (r->inc < 0.0f))) r->inc = 0.0f;
return r->curr;
}
float tRamp_sample(tRamp* const r) {
return r->curr;
}
void tRampSampleRateChanged(tRamp* const r)
{
r->inv_sr_ms = 1.0f / (leaf.sampleRate * 0.001f);
r->inc = ((r->dest-r->curr)/r->time * r->inv_sr_ms)*((float)r->samples_per_tick);
}
// If stack contains note, returns index. Else returns -1;
int tStack_contains(tStack* const ns, uint16_t noteVal)
{
for (int i = 0; i < ns->size; i++)
{
if (ns->data[i] == noteVal) return i;
}
return -1;
}
void tStack_add(tStack* const ns, uint16_t noteVal)
{
uint8_t j;
int whereToInsert = 0;
if (ns->ordered)
{
for (j = 0; j < ns->size; j++)
{
if (noteVal > ns->data[j])
{
if ((noteVal < ns->data[j+1]) || (ns->data[j+1] == -1))
{
whereToInsert = j+1;
break;
}
}
}
}
//first move notes that are already in the stack one position to the right
for (j = ns->size; j > whereToInsert; j--)
{
ns->data[j] = ns->data[(j - 1)];
}
//then, insert the new note into the front of the stack
ns->data[whereToInsert] = noteVal;
ns->size++;
}
int tStack_addIfNotAlreadyThere(tStack* const ns, uint16_t noteVal)
{
uint8_t j;
int added = 0;
if (tStack_contains(ns, noteVal) == -1)
{
int whereToInsert = 0;
if (ns->ordered)
{
for (j = 0; j < ns->size; j++)
{
if (noteVal > ns->data[j])
{
if ((noteVal < ns->data[j+1]) || (ns->data[j+1] == -1))
{
whereToInsert = j+1;
break;
}
}
}
}
//first move notes that are already in the stack one position to the right
for (j = ns->size; j > whereToInsert; j--)
{
ns->data[j] = ns->data[(j - 1)];
}
//then, insert the new note into the front of the stack
ns->data[whereToInsert] = noteVal;
ns->size++;
added = 1;
}
return added;
}
// Remove noteVal. return 1 if removed, 0 if not
int tStack_remove(tStack* const ns, uint16_t noteVal)
{
uint8_t k;
int foundIndex = tStack_contains(ns, noteVal);
int removed = 0;
if (foundIndex >= 0)
{
for (k = 0; k < (ns->size - foundIndex); k++)
{
if ((k+foundIndex) >= (ns->capacity - 1))
{
ns->data[k + foundIndex] = -1;
}
else
{
ns->data[k + foundIndex] = ns->data[k + foundIndex + 1];
if ((k + foundIndex) == (ns->size - 1))
{
ns->data[k + foundIndex + 1] = -1;
}
}
}
// in case it got put on the stack multiple times
foundIndex--;
ns->size--;
removed = 1;
}
return removed;
}
// Doesn't change size of data types
void tStack_setCapacity(tStack* const ns, uint16_t cap)
{
if (cap <= 0)
ns->capacity = 1;
else if (cap <= STACK_SIZE)
ns->capacity = cap;
else
ns->capacity = STACK_SIZE;
for (int i = cap; i < STACK_SIZE; i++)
{
if ((int)ns->data[i] != -1)
{
ns->data[i] = -1;
ns->size -= 1;
}
}
if (ns->pos >= cap)
{
ns->pos = 0;
}
}
int tStack_getSize(tStack* const ns)
{
return ns->size;
}
void tStack_clear(tStack* const ns)
{
for (int i = 0; i < STACK_SIZE; i++)
{
ns->data[i] = -1;
}
ns->pos = 0;
ns->size = 0;
}
// Next item in order of addition to stack. Return 0-31 if there is a next item to move to. Returns -1 otherwise.
int tStack_next(tStack* const ns)
{
int step = 0;
if (ns->size != 0) // if there is at least one note in the stack
{
if (ns->pos > 0) // if you're not at the most recent note (first one), then go backward in the array (moving from earliest to latest)
{
ns->pos--;
}
else
{
ns->pos = (ns->size - 1); // if you are the most recent note, go back to the earliest note in the array
}
step = ns->data[ns->pos];
return step;
}
else
{
return -1;
}
}
int tStack_get(tStack* const ns, int which)
{
return ns->data[which];
}
int tStack_first(tStack* const ns)
{
return ns->data[0];
}
void tStack_init(tStack* const ns)
{
ns->ordered = OFALSE;
ns->size = 0;
ns->pos = 0;
ns->capacity = STACK_SIZE;
for (int i = 0; i < STACK_SIZE; i++) ns->data[i] = -1;
}
/******************************************************************************/
/***************** static function declarations *******************************/
/******************************************************************************/
static void solad_init(tSOLAD *w);
static inline float read_sample(tSOLAD *w, float floatindex);
static void pitchdown(tSOLAD *w, float *out);
static void pitchup(tSOLAD *w, float *out);
/******************************************************************************/
/***************** public access functions ************************************/
/******************************************************************************/
// init
void tSOLAD_init(tSOLAD* const w)
{
w->pitchfactor = 1.;
solad_init(w);
}
void tSOLAD_free(tSOLAD* const w)
{
leaf_free(w);
}
// send one block of input samples, receive one block of output samples
void tSOLAD_ioSamples(tSOLAD* const w, float* in, float* out, int blocksize)
{
int i = w->timeindex;
int n = w->blocksize = blocksize;
if(!i) w->delaybuf[LOOPSIZE] = in[0]; // copy one sample for interpolation
while(n--) w->delaybuf[i++] = *in++; // copy one input block to delay buffer
if(w->pitchfactor > 1) pitchup(w, out);
else pitchdown(w, out);
w->timeindex += blocksize;
w->timeindex &= LOOPMASK;
}
// set periodicity analysis data
void tSOLAD_setPeriod(tSOLAD* const w, float period)
{
if(period > MAXPERIOD) period = MAXPERIOD;
if(period > MINPERIOD) w->period = period; // ignore period when too small
}
// set pitch factor between 0.25 and 4
void tSOLAD_setPitchFactor(tSOLAD* const w, float pitchfactor)
{
if(pitchfactor < 0.25) pitchfactor = 0.25;
else if(pitchfactor > 4.) pitchfactor = 4.;
w->pitchfactor = pitchfactor;
}
// force readpointer lag
void tSOLAD_setReadLag(tSOLAD* const w, float readlag)
{
if(readlag < 0) readlag = 0;
if(readlag < w->readlag) // do not jump backward, only forward
{
w->jump = w->readlag - readlag;
w->readlag = readlag;
w->xfadelength = readlag;
w->xfadevalue = 1;
}
}
// reset state variables
void tSOLAD_resetState(tSOLAD* const w)
{
int n = LOOPSIZE + 1;
float *buf = w->delaybuf;
while(n--) *buf++ = 0;
solad_init(w);
}
/******************************************************************************/
/******************** private procedures **************************************/
/******************************************************************************/
/*
Function pitchdown() is called to read samples from the delay buffer when pitch
factor is between 0.25 and 1. The read pointer lags behind because of the slowed
down speed, and it must jump forward towards the write pointer soon as there is
sufficient space to jump. That is, if there is at least one period of the input
signal between read pointer and write pointer. When short periods follow up on
long periods, the read pointer may have space to jump over more than one period
lenghts. Jump length must be [periodlength ^ 2] in any case.
A linear crossfade function joins the jump-from point with the jump-to point.
The crossfade must be completed before another read pointer jump is allowed.
Length of the crossfade function is stored as a number of samples in terms of
the input sample rate. This length is dynamically translated
to a crossfade length expressed in output reading rate, according to pitch
factor which can change before the crossfade is completed. Crossfade length does
not cover an invariable length in periods for all pitch transposition factors.
For pitch factors from 0.5 till 1, crossfade length is stretched in the
output just as much as the signal itself, as crossfade speed is set to equal
pitch factor. For pitch factors below 0.5, the read pointer wants to jump
forward before one period is read, therefore the crossfade length as expressed
in output periods must be shorter. Crossfade speed is set to [1 - pitchfactor]
for those cases. Pitch factor 0.5 is the natural switch point between crossfade
speeds [pitchfactor] and [1 - pitchfactor] because 0.5 == 1 - 0.5. The crossfade
speed modification for pitch factors below 0.5 also means that much of the
original signal content will be skipped.
*/
static void pitchdown(tSOLAD* const w, float *out)
{
int n = w->blocksize;
float refindex = (float)(w->timeindex + LOOPSIZE); // no negative values!
float pitchfactor = w->pitchfactor;
float period = w->period;
float readlag = w->readlag;
float readlagstep = 1 - pitchfactor;
float jump = w->jump;
float xfadevalue = w->xfadevalue;
float xfadelength = w->xfadelength;
float xfadespeed, xfadestep, readindex, outputsample;
if(pitchfactor > 0.5) xfadespeed = pitchfactor;
else xfadespeed = 1 - pitchfactor;
xfadestep = xfadespeed / xfadelength;
while(n--)
{
if(readlag > period) // check if read pointer may jump forward...
{
if(xfadevalue <= 0) // ...but do not interrupt crossfade
{
jump = period; // jump forward
while((jump * 2) < readlag) jump *= 2; // use available space
readlag -= jump; // reduce read pointer lag
xfadevalue = 1; // start crossfade
xfadelength = period - 1;
xfadestep = xfadespeed / xfadelength;
}
}
readindex = refindex - readlag;
outputsample = read_sample(w, readindex);
if(xfadevalue > 0)
{
outputsample *= (1 - xfadevalue); // fadein
outputsample += read_sample(w, readindex - jump) * xfadevalue; // fadeout
xfadevalue -= xfadestep;
}
*out++ = outputsample;
refindex += 1;
readlag += readlagstep;
}
w->jump = jump; // state variables
w->readlag = readlag;
w->xfadevalue = xfadevalue;
w->xfadelength = xfadelength;
}
/*
Function pitchup() for pitch factors above 1 is more complicated than
pitchdown(). The read pointer increments faster than the write pointer and a
backward jump must happen in time, reckoning with the crossfade region. The read
pointer backward jump length is always one period. In order to minimize the area
of signal duplicates, crossfade length is aimed at [period / pitchfactor].
This leads to a crossfade speed of [pitchfactor * pitchfactor].
Some samples for the fade out (but not all of them) must already be in the
buffer, otherwise we will run out of input samples before the crossfade is
completed. The ratio of past samples and future samples for a crossfade of any
length is as follows:
past samples: xfadelength * (1 - 1 / pitchfactor)
future samples: xfadelength * (1 / pitchfactor)
For example in the case of pitch factor 1.5 this would be:
past samples: xfadelength * (1 - 1 / 1.5) = xfadelength * 1 / 3
future samples: xfadelength * (1 / 1.5) = xfadelength * 2 / 3
In the case of pitch factor 4 this would be:
past samples: xfadelength * (1 - 1 / 4) = xfadelength * 3 / 4
future samples: xfadelength * (1 / 4) = xfadelength * 1 / 4
The read pointer lag must therefore preserve a minimum dependent on pitch
factor. The minimum is called 'limit' here:
limit = period * (pitchfactor - 1) / pitchfactor * pitchfactor
Components of this expression are combined to reuse them in operations, while
(pitchfactor - 1) is changed to (pitchfactor - 0.99) to avoid numerical
resolution issues for pitch factors slightly above 1:
xfadespeed = pitchfactor * pitchfactor
limitfactor = (pitchfactor - 0.99) / xfadespeed
limit = period * limitfactor
When read lag is smaller than this limit, the read pointer must preferably
jump backward, unless a previous crossfade is not yet completed. Crossfades must
preferably be completed, unless the read pointer lag becomes smaller than zero.
With fluctuating period lengths and pitch factors, the readpointer lag limit may
change from one input block to the next in such a way that the actual lag is
suddenly much smaller than the limit, and the intended crossfade length can not
be applied. Therefore the crossfade length is simply calculated from the
available amount of samples for all cases, like so:
xfadelength = readlag / limitfactor
For most occurrences, this will amount to a crossfade length reduced to
[period / pitchfactor] in the output for pitch factors above 1, while in some
cases it will be considerably shorter. Fortunately, an incidental aberration of
the intended crossfade length hardly ever creates an audible artifact. The
reason to specify preferred crossfade length according to pitch factor is to
minimize the impression of echoes without sacrificing too much of the signal
content. The readpointer jump length remains one period in any case.
Sometimes, the input signal periodicity may decrease substantially between one
signal block and the next. In such cases it may be possible for the read pointer
to jump forward and reduce latency. For every signal block, a check on this
possibility is done. A previous crossfade must be completed before a forward
jump is allowed.
*/
static void pitchup(tSOLAD* const w, float *out)
{
int n = w->blocksize;
float refindex = (float)(w->timeindex + LOOPSIZE); // no negative values
float pitchfactor = w->pitchfactor;
float period = w->period;
float readlag = w->readlag;
float jump = w->jump;
float xfadevalue = w->xfadevalue;
float xfadelength = w->xfadelength;
float readlagstep = pitchfactor - 1;
float xfadespeed = pitchfactor * pitchfactor;
float xfadestep = xfadespeed / xfadelength;
float limitfactor = (pitchfactor - (float)0.99) / xfadespeed;
float limit = period * limitfactor;
float readindex, outputsample;
if((readlag > (period + 2 * limit)) & (xfadevalue < 0))
{
jump = period; // jump forward
while((jump * 2) < (readlag - 2 * limit)) jump *= 2; // use available space
readlag -= jump; // reduce read pointer lag
xfadevalue = 1; // start crossfade
xfadelength = period - 1;
xfadestep = xfadespeed / xfadelength;
}
while(n--)
{
if(readlag < limit) // check if read pointer should jump backward...
{
if((xfadevalue < 0) | (readlag < 0)) // ...but try not to interrupt crossfade
{
xfadelength = readlag / limitfactor;
if(xfadelength < 1) xfadelength = 1;
xfadestep = xfadespeed / xfadelength;
jump = -period; // jump backward
readlag += period; // increase read pointer lag
xfadevalue = 1; // start crossfade
}
}
readindex = refindex - readlag;
outputsample = read_sample(w, readindex);
if(xfadevalue > 0)
{
outputsample *= (1 - xfadevalue);
outputsample += read_sample(w, readindex - jump) * xfadevalue;
xfadevalue -= xfadestep;
}
*out++ = outputsample;
refindex += 1;
readlag -= readlagstep;
}
w->readlag = readlag; // state variables
w->jump = jump;
w->xfadelength = xfadelength;
w->xfadevalue = xfadevalue;
}
// read one sample from delay buffer, with linear interpolation
static inline float read_sample(tSOLAD* const w, float floatindex)
{
int index = (int)floatindex;
float fraction = floatindex - (float)index;
float *buf = w->delaybuf;
index &= LOOPMASK;
return (buf[index] + (fraction * (buf[index+1] - buf[index])));
}
static void solad_init(tSOLAD* const w)
{
w->timeindex = 0;
w->xfadevalue = -1;
w->period = INITPERIOD;
w->readlag = INITPERIOD;
w->blocksize = INITPERIOD;
}
/******************************************************************************/
/***************************** private procedures *****************************/
/******************************************************************************/
#define REALFFT mayer_realfft
#define REALIFFT mayer_realifft
static void snac_analyzeframe(tSNAC* const s);
static void snac_autocorrelation(tSNAC* const s);
static void snac_normalize(tSNAC* const s);
static void snac_pickpeak(tSNAC* const s);
static void snac_periodandfidelity(tSNAC* const s);
static void snac_biasbuf(tSNAC* const s);
static float snac_spectralpeak(tSNAC* const s, float periodlength);
/******************************************************************************/
/******************************** constructor, destructor *********************/
/******************************************************************************/
void tSNAC_init(tSNAC* const s, int overlaparg)
{
s->biasfactor = DEFBIAS;
s->timeindex = 0;
s->periodindex = 0;
s->periodlength = 0.;
s->fidelity = 0.;
s->minrms = DEFMINRMS;
s->framesize = SNAC_FRAME_SIZE;
snac_biasbuf(s);
tSNAC_setOverlap(s, overlaparg);
}
void tSNAC_free(tSNAC* const s)
{
leaf_free(s);
}
/******************************************************************************/
/************************** public access functions****************************/
/******************************************************************************/
void tSNAC_ioSamples(tSNAC* const s, float *in, float *out, int size)
{
int timeindex = s->timeindex;
int mask = s->framesize - 1;
int outindex = 0;
float *inputbuf = s->inputbuf;
float *processbuf = s->processbuf;
// call analysis function when it is time
if(!(timeindex & (s->framesize / s->overlap - 1))) snac_analyzeframe(s);
while(size--)
{
inputbuf[timeindex] = *in++;
out[outindex++] = processbuf[timeindex++];
timeindex &= mask;
}
s->timeindex = timeindex;
}
void tSNAC_setOverlap(tSNAC* const s, int lap)
{
if(!((lap==1)|(lap==2)|(lap==4)|(lap==8))) lap = DEFOVERLAP;
s->overlap = lap;
}
void tSNAC_setBias(tSNAC* const s, float bias)
{
if(bias > 1.) bias = 1.;
if(bias < 0.) bias = 0.;
s->biasfactor = bias;
snac_biasbuf(s);
return;
}
void tSNAC_setMinRMS(tSNAC* const s, float rms)
{
if(rms > 1.) rms = 1.;
if(rms < 0.) rms = 0.;
s->minrms = rms;
return;
}
float tSNAC_getPeriod(tSNAC* const s)
{
return(s->periodlength);
}
float tSNAC_getFidelity(tSNAC* const s)
{
return(s->fidelity);
}
/******************************************************************************/
/***************************** private procedures *****************************/
/******************************************************************************/
// main analysis function
static void snac_analyzeframe(tSNAC* const s)
{
int n, tindex = s->timeindex;
int framesize = s->framesize;
int mask = framesize - 1;
float norm = 1. / sqrt((float)(framesize * 2));
float *inputbuf = s->inputbuf;
float *processbuf = s->processbuf;
// copy input to processing buffers
for(n=0; n<framesize; n++)
{
processbuf[n] = inputbuf[tindex] * norm;
tindex++;
tindex &= mask;
}
// zeropadding
for(n=framesize; n<(framesize<<1); n++) processbuf[n] = 0.;
// call analysis procedures
snac_autocorrelation(s);
snac_normalize(s);
snac_pickpeak(s);
snac_periodandfidelity(s);
}
static void snac_autocorrelation(tSNAC* const s)
{
int n, m;
int framesize = s->framesize;
int fftsize = framesize * 2;
float *processbuf = s->processbuf;
float *spectrumbuf = s->spectrumbuf;
REALFFT(fftsize, processbuf);
// compute power spectrum
processbuf[0] *= processbuf[0]; // DC
processbuf[framesize] *= processbuf[framesize]; // Nyquist
for(n=1; n<framesize; n++)
{
processbuf[n] = processbuf[n] * processbuf[n]
+ processbuf[fftsize-n] * processbuf[fftsize-n]; // imag coefficients appear reversed
processbuf[fftsize-n] = 0.;
}
// store power spectrum up to SR/4 for possible later use
for(m=0; m<(framesize>>1); m++)
{
spectrumbuf[m] = processbuf[m];
}
// transform power spectrum to autocorrelation function
REALIFFT(fftsize, processbuf);
return;
}
static void snac_normalize(tSNAC* const s)
{
int framesize = s->framesize;
int framesizeplustimeindex = s->framesize + s->timeindex;
int timeindexminusone = s->timeindex - 1;
int n, m;
int mask = framesize - 1;
int seek = framesize * SEEK;
float *inputbuf = s->inputbuf;
float *processbuf= s->processbuf;
float signal1, signal2;
// minimum RMS implemented as minimum autocorrelation at index 0
// functionally equivalent to white noise floor
float rms = s->minrms / sqrt(1.0f / (float)framesize);
float minrzero = rms * rms;
float rzero = processbuf[0];
if(rzero < minrzero) rzero = minrzero;
double normintegral = (double)rzero * 2.;
// normalize biased autocorrelation function
// inputbuf is circular buffer: timeindex may be non-zero when overlap > 1
processbuf[0] = 1;
for(n=1, m=s->timeindex+1; n<seek; n++, m++)
{
signal1 = inputbuf[(n + timeindexminusone)&mask];
signal2 = inputbuf[(framesizeplustimeindex - n)&mask];
normintegral -= (double)(signal1 * signal1 + signal2 * signal2);
processbuf[n] /= (float)normintegral * 0.5f;
}
// flush instable function tail
for(n = seek; n<framesize; n++) processbuf[n] = 0.;
return;
}
static void snac_periodandfidelity(tSNAC* const s)
{
float periodlength;
if(s->periodindex)
{
periodlength = (float)s->periodindex +
interpolate3phase(s->processbuf, s->periodindex);
if(periodlength < 8) periodlength = snac_spectralpeak(s, periodlength);
s->periodlength = periodlength;
s->fidelity = interpolate3max(s->processbuf, s->periodindex);
}
return;
}
// select the peak which most probably represents period length
static void snac_pickpeak(tSNAC* const s)
{
int n, peakindex=0;
int seek = s->framesize * SEEK;
float *processbuf= s->processbuf;
float maxvalue = 0.;
float biasedpeak;
float *biasbuf = s->biasbuf;
// skip main lobe
for(n=1; n<seek; n++)
{
if(processbuf[n] < 0.) break;
}
// find interpolated / biased maximum in SNAC function
// interpolation finds the 'real maximum'
// biasing favours the first candidate
for(; n<seek-1; n++)
{
if(processbuf[n] >= processbuf[n-1])
{
if(processbuf[n] > processbuf[n+1]) // we have a local peak
{
biasedpeak = interpolate3max(processbuf, n) * biasbuf[n];
if(biasedpeak > maxvalue)
{
maxvalue = biasedpeak;
peakindex = n;
}
}
}
}
s->periodindex = peakindex;
return;
}
// verify period length via frequency domain (up till SR/4)
// frequency domain is more precise than lag domain for period lengths < 8
// argument 'periodlength' is initial estimation from autocorrelation
static float snac_spectralpeak(tSNAC* const s, float periodlength)
{
if(periodlength < 4.) return periodlength;
float max = 0.;
int n, startbin, stopbin, peakbin = 0;
int spectrumsize = s->framesize>>1;
float *spectrumbuf = s->spectrumbuf;
float peaklocation = (float)(s->framesize * 2.) / periodlength;
startbin = (int)(peaklocation * 0.8 + 0.5);
if(startbin < 1) startbin = 1;
stopbin = (int)(peaklocation * 1.25 + 0.5);
if(stopbin >= spectrumsize - 1) stopbin = spectrumsize - 1;
for(n=startbin; n<stopbin; n++)
{
if(spectrumbuf[n] >= spectrumbuf[n-1])
{
if(spectrumbuf[n] > spectrumbuf[n+1])
{
if(spectrumbuf[n] > max)
{
max = spectrumbuf[n];
peakbin = n;
}
}
}
}
// calculate amplitudes in peak region
for(n=(peakbin-1); n<(peakbin+2); n++)
{
spectrumbuf[n] = sqrt(spectrumbuf[n]);
}
peaklocation = (float)peakbin + interpolate3phase(spectrumbuf, peakbin);
periodlength = (float)(s->framesize * 2.0f) / peaklocation;
return periodlength;
}
// modified logarithmic bias function
static void snac_biasbuf(tSNAC* const s)
{
int n;
int maxperiod = (int)(s->framesize * (float)SEEK);
float bias = s->biasfactor / log((float)(maxperiod - 4));
float *biasbuf = s->biasbuf;
for(n=0; n<5; n++) // periods < 5 samples can't be tracked
{
biasbuf[n] = 0.;
}
for(n=5; n<maxperiod; n++)
{
biasbuf[n] = 1.0f - (float)log(n - 4) * bias;
}
}
/********Private function prototypes**********/
static void atkdtk_init(tAtkDtk* const a, int blocksize, int atk, int rel);
static void atkdtk_envelope(tAtkDtk* const a, float *in);
/********Constructor/Destructor***************/
void tAtkDtk_init(tAtkDtk* const a, int blocksize)
{
atkdtk_init(a, blocksize, DEFATTACK, DEFRELEASE);
}
void tAtkDtk_init_expanded(tAtkDtk* const a, int blocksize, int atk, int rel)
{
atkdtk_init(a, blocksize, atk, rel);
}
void tAtkDtk_free(tAtkDtk *a)
{
leaf_free(a);
}
/*******Public Functions***********/
void tAtkDtk_setBlocksize(tAtkDtk* const a, int size)
{
if(!((size==64)|(size==128)|(size==256)|(size==512)|(size==1024)|(size==2048)))
size = DEFBLOCKSIZE;
a->blocksize = size;
return;
}
void tAtkDtk_setSamplerate(tAtkDtk* const a, int inRate)
{
a->samplerate = inRate;
//Reset atk and rel to recalculate coeff
tAtkDtk_setAtk(a, a->atk);
tAtkDtk_setRel(a, a->rel);
return;
}
void tAtkDtk_setThreshold(tAtkDtk* const a, float thres)
{
a->threshold = thres;
return;
}
void tAtkDtk_setAtk(tAtkDtk* const a, int inAtk)
{
a->atk = inAtk;
a->atk_coeff = pow(0.01, 1.0/(a->atk * a->samplerate * 0.001));
return;
}
void tAtkDtk_setRel(tAtkDtk* const a, int inRel)
{
a->rel = inRel;
a->rel_coeff = pow(0.01, 1.0/(a->rel * a->samplerate * 0.001));
return;
}
int tAtkDtk_detect(tAtkDtk* const a, float *in)
{
int result;
atkdtk_envelope(a, in);
if(a->env >= a->prevAmp*2) //2 times greater = 6dB increase
result = 1;
else
result = 0;
a->prevAmp = a->env;
return result;
}
/*******Private Functions**********/
static void atkdtk_init(tAtkDtk* const a, int blocksize, int atk, int rel)
{
a->env = 0;
a->blocksize = blocksize;
a->threshold = DEFTHRESHOLD;
a->samplerate = leaf.sampleRate;
a->prevAmp = 0;
a->env = 0;
tAtkDtk_setAtk(a, atk);
tAtkDtk_setRel(a, rel);
}
static void atkdtk_envelope(tAtkDtk* const a, float *in)
{
int i = 0;
float tmp;
for(i = 0; i < a->blocksize; ++i){
tmp = fastabs(in[i]);
if(tmp > a->env)
a->env = a->atk_coeff * (a->env - tmp) + tmp;
else
a->env = a->rel_coeff * (a->env - tmp) + tmp;
}
}