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/* Copyright 2012 Dietrich Epp <depp@zdome.net> */
#include "param.h"
void lfr_param::seti(lfr_param_t pname, int value)
{
int n = pname;
if (n < 0 || n >= LFR_PARAM_COUNT)
return;
set |= 1u << n;
current = 0;
param[n] = (double) value;
}
void lfr_param::setf(lfr_param_t pname, double value)
{
int n = pname;
if (n < 0 || n >= LFR_PARAM_COUNT)
return;
set |= 1u << n;
current = 0;
param[n] = value;
}
void lfr_param::geti(lfr_param_t pname, int *value)
{
int n = pname;
if (n < 0 || n >= LFR_PARAM_COUNT)
return;
if (!current)
calculate();
*value = static_cast<int>(param[n] + 0.5);
}
void lfr_param::getf(lfr_param_t pname, double *value)
{
int n = pname;
if (n < 0 || n >= LFR_PARAM_COUNT)
return;
if (!current)
calculate();
*value = param[n];
}
constexpr auto MAX_QUALITY = 10;
struct lfr_quality {
unsigned short atten; /* dB */
unsigned short transition; /* out of 1000 */
unsigned short kind; /* 0 = loose, 2 = maxfreq=0 */
unsigned short minfpass; /* out of 1000 */
};
constexpr lfr_quality LFR_QUALITY[MAX_QUALITY + 1] = {
{ 35, 350, 0, 500 },
{ 35, 350, 0, 500 },
{ 35, 350, 0, 500 }, /* low */
{ 35, 350, 0, 500 },
{ 50, 290, 0, 600 },
{ 60, 230, 1, 700 }, /* medium */
{ 80, 180, 1, 800 },
{ 90, 140, 1, 850 },
{ 96, 100, 1, 900 }, /* high */
{ 108, 60, 2, 915 },
{ 120, 30, 2, 930 } /* ultra */
};
constexpr auto MIN_OUTPUT = 1.0 / 128;
constexpr auto MIN_ATTEN = 13;
constexpr auto MAX_ATTEN = 144;
constexpr auto MIN_TRANSITION = 1.0 / 256.0;
constexpr auto MAX_MINPASS = 31.0 / 32.0;
constexpr auto MIN_MINPASS = 8.0 / 32.0;
#define ISSET(n) ((set & (1u << (LFR_PARAM_ ## n))) != 0)
#define GETF(n) (param[LFR_PARAM_ ## n])
#define GETI(n) (static_cast<int>(GETF(n) + 0.5))
void lfr_param::calculate()
{
int qual;
double rate;
double f_output, f_transition, f_maxfreq, f_minpass;
double atten, f_stop, f_pass;
double t;
int loose;
/* Quality */
if (ISSET(QUALITY)) {
qual = GETI(QUALITY);
if (qual < 0)
qual = 0;
else if (qual > MAX_QUALITY)
qual = MAX_QUALITY;
} else {
qual = 8;
}
GETF(QUALITY) = qual;
/* Input rate */
if (ISSET(INRATE)) {
rate = GETF(INRATE);
if (rate <= 0)
rate = -1.0;
} else {
rate = -1.0;
}
GETF(INRATE) = rate;
/* Output rate */
if (ISSET(OUTRATE)) {
t = GETF(OUTRATE);
if (rate > 0) {
if (t > rate) {
f_output = 1.0;
GETF(OUTRATE) = rate;
} else {
f_output = t / rate;
if (f_output < MIN_OUTPUT) {
f_output = MIN_OUTPUT;
GETF(OUTRATE) = MIN_OUTPUT * rate;
}
}
} else {
if (t >= 1.0) {
f_output = 1.0;
GETF(OUTRATE) = 1.0;
} else {
f_output = t;
if (f_output < MIN_OUTPUT) {
f_output = MIN_OUTPUT;
GETF(OUTRATE) = MIN_OUTPUT;
}
}
}
} else {
f_output = 1.0;
if (rate > 0)
GETF(OUTRATE) = 1.0;
else
GETF(OUTRATE) = rate;
}
/* Transition bandwidth */
if (ISSET(FTRANSITION)) {
f_transition = GETF(FTRANSITION);
if (f_transition < MIN_TRANSITION)
f_transition = 1.0/32;
if (f_transition > 1.0)
f_transition = 1.0;
} else {
f_transition = (0.5/1000) * (double) LFR_QUALITY[qual].transition;
}
GETF(FTRANSITION) = f_transition;
/* Maximum audible frequency */
if (ISSET(MAXFREQ)) {
f_maxfreq = GETF(MAXFREQ);
} else {
if (LFR_QUALITY[qual].kind < 2)
f_maxfreq = 20000.0;
else
f_maxfreq = -1;
GETF(MAXFREQ) = f_maxfreq;
}
if (rate > 0)
f_maxfreq = f_maxfreq / rate;
else
f_maxfreq = 1.0;
/* "Loose" flag */
if (ISSET(LOOSE)) {
loose = GETI(LOOSE) > 0;
} else {
loose = LFR_QUALITY[qual].kind < 1;
}
GETF(LOOSE) = (double) loose;
/* Minimum output bandwidth */
if (ISSET(MINFPASS)) {
f_minpass = GETF(MINFPASS);
if (f_minpass < MIN_MINPASS)
f_minpass = MIN_MINPASS;
else if (f_minpass > MAX_MINPASS)
f_minpass = MAX_MINPASS;
} else {
f_minpass = 0.001 * LFR_QUALITY[qual].minfpass;
}
GETF(MINFPASS) = f_minpass;
/* Stop band attenuation */
if (ISSET(ATTEN)) {
atten = GETF(ATTEN);
if (atten < MIN_ATTEN)
atten = MIN_ATTEN;
else if (atten > MAX_ATTEN)
atten = MAX_ATTEN;
} else {
atten = (double) LFR_QUALITY[qual].atten;
}
GETF(ATTEN) = atten;
/* Stop band frequency */
if (ISSET(FSTOP)) {
f_stop = GETF(FSTOP);
if (f_stop > 1.0)
f_stop = 1.0;
else if (f_stop < MIN_TRANSITION)
f_stop = MIN_TRANSITION;
} else {
f_stop = 0.5 * f_output;
if (loose && f_maxfreq > 0) {
t = f_output - f_maxfreq;
if (t > f_stop)
f_stop = t;
}
}
GETF(FSTOP) = f_stop;
/* Pass band frequency */
if (ISSET(ATTEN)) {
f_pass = GETF(FPASS);
} else {
f_pass = f_stop - f_transition;
t = 0.5 * f_output * f_minpass;
if (t > f_pass)
f_pass = t;
if (f_maxfreq > 0 && f_pass > f_maxfreq)
f_pass = f_maxfreq;
}
t = f_stop - MIN_TRANSITION;
if (t < 0)
t = 0;
if (t < f_pass)
f_pass = t;
GETF(FPASS) = f_pass;
}
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