ref: 59f265b00a4a195d07dc2a0bb211009724e09c00
dir: /src/effects_i.c/
/* Implements a libSoX internal interface for implementing effects.
* All public functions & data are prefixed with lsx_ .
*
* (c) 2005-8 Chris Bagwell and SoX contributors
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or (at
* your option) any later version.
*
* This 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 Lesser
* General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifdef NDEBUG /* Enable assert always. */
#undef NDEBUG /* Must undef above assert.h or other that might include it. */
#endif
#include "sox_i.h"
#include <assert.h>
#include <string.h>
#undef sox_fail
#define sox_fail sox_globals.subsystem=effp->handler.name,sox_fail
int lsx_usage(sox_effect_t * effp)
{
if (effp->handler.usage)
sox_fail("usage: %s", effp->handler.usage);
else
sox_fail("this effect takes no parameters");
return SOX_EOF;
}
char * lsx_usage_lines(char * * usage, char const * const * lines, size_t n)
{
if (!*usage) {
size_t i, len;
for (len = i = 0; i < n; len += strlen(lines[i++]) + 1);
*usage = lsx_malloc(len);
strcpy(*usage, lines[0]);
for (i = 1; i < n; ++i) {
strcat(*usage, "\n");
strcat(*usage, lines[i]);
}
}
return *usage;
}
/* here for linear interp. might be useful for other things */
unsigned lsx_gcd(unsigned a, unsigned b)
{
if (b == 0)
return a;
else
return lsx_gcd(b, a % b);
}
unsigned lsx_lcm(unsigned a, unsigned b)
{
/* parenthesize this way to avoid unsigned overflow in product term */
return a * (b / lsx_gcd(a, b));
}
/* Numerical Recipes cubic spline */
void lsx_prepare_spline3(double const * x, double const * y, int n,
double start_1d, double end_1d, double * y_2d)
{
double p, qn, sig, un, * u = lsx_malloc((n - 1) * sizeof(*u));
int i;
if (start_1d == HUGE_VAL)
y_2d[0] = u[0] = 0; /* Start with natural spline or */
else { /* set the start first derivative */
y_2d[0] = -.5;
u[0] = (3 / (x[1] - x[0])) * ((y[1] - y[0]) / (x[1] - x[0]) - start_1d);
}
for (i = 1; i < n - 1; ++i) {
sig = (x[i] - x[i - 1]) / (x[i + 1] - x[i - 1]);
p = sig * y_2d[i - 1] + 2;
y_2d[i] = (sig - 1) / p;
u[i] = (y[i + 1] - y[i]) / (x[i + 1] - x[i]) -
(y[i] - y[i - 1]) / (x[i] - x[i - 1]);
u[i] = (6 * u[i] / (x[i + 1] - x[i - 1]) - sig * u[i - 1]) / p;
}
if (end_1d == HUGE_VAL)
qn = un = 0; /* End with natural spline or */
else { /* set the end first derivative */
qn = .5;
un = 3 / (x[n - 1] - x[n - 2]) * (end_1d - (y[n - 1] - y[n - 2]) / (x[n - 1] - x[n - 2]));
}
y_2d[n - 1] = (un - qn * u[n - 2]) / (qn * y_2d[n - 2] + 1);
for (i = n - 2; i >= 0; --i)
y_2d[i] = y_2d[i] * y_2d[i + 1] + u[i];
free(u);
}
double lsx_spline3(double const * x, double const * y, double const * y_2d,
int n, double x1)
{
int t, i[2] = {0, 0};
double d, a, b;
for (i[1] = n - 1; i[1] - i[0] > 1; t = (i[1] + i[0]) >> 1, i[x[t] > x1] = t);
d = x[i[1]] - x[i[0]];
assert(d != 0);
a = (x[i[1]] - x1) / d;
b = (x1 - x[i[0]]) / d;
return a * y[i[0]] + b * y[i[1]] +
((a * a * a - a) * y_2d[i[0]] + (b * b * b - b) * y_2d[i[1]]) * d * d / 6;
}
sox_enum_item const lsx_wave_enum[] = {
ENUM_ITEM(SOX_WAVE_,SINE)
ENUM_ITEM(SOX_WAVE_,TRIANGLE)
{0, 0}};
void lsx_generate_wave_table(
lsx_wave_t wave_type,
sox_data_t data_type,
void *table,
size_t table_size,
double min,
double max,
double phase)
{
uint32_t t;
uint32_t phase_offset = phase / M_PI / 2 * table_size + 0.5;
for (t = 0; t < table_size; t++)
{
uint32_t point = (t + phase_offset) % table_size;
double d;
switch (wave_type)
{
case SOX_WAVE_SINE:
d = (sin((double)point / table_size * 2 * M_PI) + 1) / 2;
break;
case SOX_WAVE_TRIANGLE:
d = (double)point * 2 / table_size;
switch (4 * point / table_size)
{
case 0: d = d + 0.5; break;
case 1: case 2: d = 1.5 - d; break;
case 3: d = d - 1.5; break;
}
break;
default: /* Oops! FIXME */
d = 0.0; /* Make sure we have a value */
break;
}
d = d * (max - min) + min;
switch (data_type)
{
case SOX_FLOAT:
{
float *fp = (float *)table;
*fp++ = (float)d;
table = fp;
continue;
}
case SOX_DOUBLE:
{
double *dp = (double *)table;
*dp++ = d;
table = dp;
continue;
}
default: break;
}
d += d < 0? -0.5 : +0.5;
switch (data_type)
{
case SOX_SHORT:
{
short *sp = table;
*sp++ = (short)d;
table = sp;
continue;
}
case SOX_INT:
{
int *ip = table;
*ip++ = (int)d;
table = ip;
continue;
}
default: break;
}
}
}
/*
* lsx_parsesamples
*
* Parse a string for # of samples. If string ends with a 's'
* then the string is interpreted as a user calculated # of samples.
* If string contains ':' or '.' or if it ends with a 't' then its
* treated as an amount of time. This is converted into seconds and
* fraction of seconds and then use the sample rate to calculate
* # of samples.
* Returns NULL on error, pointer to next char to parse otherwise.
*/
char const * lsx_parsesamples(sox_rate_t rate, const char *str0, size_t *samples, int def)
{
int i, found_samples = 0, found_time = 0;
char const * end;
char const * pos;
sox_bool found_colon, found_dot;
char * str = (char *)str0;
for (;*str == ' '; ++str);
for (end = str; *end && strchr("0123456789:.ets", *end); ++end);
if (end == str)
return NULL;
pos = strchr(str, ':');
found_colon = pos && pos < end;
pos = strchr(str, '.');
found_dot = pos && pos < end;
if (found_colon || found_dot || *(end-1) == 't')
found_time = 1;
else if (*(end-1) == 's')
found_samples = 1;
if (found_time || (def == 't' && !found_samples)) {
for (*samples = 0, i = 0; *str != '.' && i < 3; ++i) {
char * last_str = str;
long part = strtol(str, &str, 10);
if (!i && str == last_str)
return NULL;
*samples += rate * part;
if (i < 2) {
if (*str != ':')
break;
++str;
*samples *= 60;
}
}
if (*str == '.') {
char * last_str = str;
double part = strtod(str, &str);
if (str == last_str)
return NULL;
*samples += rate * part + .5;
}
return *str == 't'? str + 1 : str;
}
{
char * last_str = str;
double part = strtod(str, &str);
if (str == last_str)
return NULL;
*samples = part + .5;
return *str == 's'? str + 1 : str;
}
}
#if 0
#define TEST(st, samp, len) \
str = st; \
next = lsx_parsesamples(10000, str, &samples, 't'); \
assert(samples == samp && next == str + len);
int main(int argc, char * * argv)
{
char const * str, * next;
size_t samples;
TEST("0" , 0, 1)
TEST("1" , 10000, 1)
TEST("0s" , 0, 2)
TEST("0s,", 0, 2)
TEST("0s/", 0, 2)
TEST("0s@", 0, 2)
TEST("0t" , 0, 2)
TEST("0t,", 0, 2)
TEST("0t/", 0, 2)
TEST("0t@", 0, 2)
TEST("1s" , 1, 2)
TEST("1s,", 1, 2)
TEST("1s/", 1, 2)
TEST("1s@", 1, 2)
TEST(" 01s" , 1, 4)
TEST("1e6s" , 1000000, 4)
TEST("1t" , 10000, 2)
TEST("1t,", 10000, 2)
TEST("1t/", 10000, 2)
TEST("1t@", 10000, 2)
TEST("1.1t" , 11000, 4)
TEST("1.1t,", 11000, 4)
TEST("1.1t/", 11000, 4)
TEST("1.1t@", 11000, 4)
TEST("1e6t" , 10000, 1)
TEST(".0", 0, 2)
TEST("0.0", 0, 3)
TEST("0:0.0", 0, 5)
TEST("0:0:0.0", 0, 7)
TEST(".1", 1000, 2)
TEST(".10", 1000, 3)
TEST("0.1", 1000, 3)
TEST("1.1", 11000, 3)
TEST("1:1.1", 611000, 5)
TEST("1:1:1.1", 36611000, 7)
TEST("1:1", 610000, 3)
TEST("1:01", 610000, 4)
TEST("1:1:1", 36610000, 5)
TEST("1:", 600000, 2)
TEST("1::", 36000000, 3)
TEST("0.444444", 4444, 8)
TEST("0.555555", 5556, 8)
assert(!lsx_parsesamples(10000, "x", &samples, 't'));
return 0;
}
#endif
/* a note is given as an int,
* 0 => 440 Hz = A
* >0 => number of half notes 'up',
* <0 => number of half notes down,
* example 12 => A of next octave, 880Hz
*
* calculated by freq = 440Hz * 2**(note/12)
*/
static double calc_note_freq(double note)
{
return 440.0 * pow(2.0, note / 12.0);
}
/* Read string 'text' and convert to frequency.
* 'text' can be a positive number which is the frequency in Hz.
* If 'text' starts with a hash '%' and a following number the corresponding
* note is calculated.
* Return -1 on error.
*/
double lsx_parse_frequency(char const * text, char * * end_ptr)
{
double result;
if (*text == '%') {
result = strtod(text + 1, end_ptr);
if (*end_ptr == text + 1)
return -1;
return calc_note_freq(result);
}
result = strtod(text, end_ptr);
if (end_ptr) {
if (*end_ptr == text)
return -1;
if (**end_ptr == 'k') {
result *= 1000;
++*end_ptr;
}
}
return result < 0 ? -1 : result;
}
double lsx_bessel_I_0(double x)
{
double term = 1, sum = 1, last_sum, x2 = x / 2;
int i = 1;
do {
double y = x2 / i++;
last_sum = sum, sum += term *= y * y;
} while (sum != last_sum);
return sum;
}
int lsx_set_dft_length(int num_taps) /* Set to 4 x nearest power of 2 */
{
int result, n = num_taps;
for (result = 8; n > 2; result <<= 1, n >>= 1);
result = range_limit(result, 4096, 131072);
assert(num_taps * 2 < result);
return result;
}
#include "fft4g.h"
int * lsx_fft_br;
double * lsx_fft_sc;
static void update_fft_cache(int len)
{
static int n;
if (!len) {
free(lsx_fft_br);
free(lsx_fft_sc);
lsx_fft_sc = NULL;
lsx_fft_br = NULL;
n = 0;
return;
}
if (len > n) {
int old_n = n;
n = len;
lsx_fft_br = lsx_realloc(lsx_fft_br, dft_br_len(n) * sizeof(*lsx_fft_br));
lsx_fft_sc = lsx_realloc(lsx_fft_sc, dft_sc_len(n) * sizeof(*lsx_fft_sc));
if (!old_n)
lsx_fft_br[0] = 0;
}
}
static sox_bool is_power_of_2(int x)
{
return !(x < 2 || (x & (x - 1)));
}
void lsx_safe_rdft(int len, int type, double * d)
{
assert(is_power_of_2(len));
update_fft_cache(len);
lsx_rdft(len, type, d, lsx_fft_br, lsx_fft_sc);
}
void lsx_safe_cdft(int len, int type, double * d)
{
assert(is_power_of_2(len));
update_fft_cache(len);
lsx_cdft(len, type, d, lsx_fft_br, lsx_fft_sc);
}
void lsx_power_spectrum(int n, double const * in, double * out)
{
int i;
double * work = lsx_memdup(in, n * sizeof(*work));
lsx_safe_rdft(n, 1, work);
out[0] = sqr(work[0]);
for (i = 2; i < n; i += 2)
out[i >> 1] = sqr(work[i]) + sqr(work[i + 1]);
out[i >> 1] = sqr(work[1]);
free(work);
}
void lsx_power_spectrum_f(int n, float const * in, float * out)
{
int i;
double * work = lsx_malloc(n * sizeof(*work));
for (i = 0; i< n; ++i) work[i] = in[i];
lsx_safe_rdft(n, 1, work);
out[0] = sqr(work[0]);
for (i = 2; i < n; i += 2)
out[i >> 1] = sqr(work[i]) + sqr(work[i + 1]);
out[i >> 1] = sqr(work[1]);
free(work);
}
void lsx_apply_hann_f(float h[], const int num_points)
{
int i, m = num_points - 1;
for (i = 0; i < num_points; ++i) {
double x = 2 * M_PI * i / m;
h[i] *= .5 - .5 * cos(x);
}
}
void lsx_apply_hann(double h[], const int num_points)
{
int i, m = num_points - 1;
for (i = 0; i < num_points; ++i) {
double x = 2 * M_PI * i / m;
h[i] *= .5 - .5 * cos(x);
}
}
void lsx_apply_hamming(double h[], const int num_points)
{
int i, m = num_points - 1;
for (i = 0; i < num_points; ++i) {
double x = 2 * M_PI * i / m;
h[i] *= .53836 - .46164 * cos(x);
}
}
void lsx_apply_bartlett(double h[], const int num_points)
{
int i, m = num_points - 1;
for (i = 0; i < num_points; ++i) {
h[i] *= 2. / m * (m / 2. - fabs(i - m / 2.));
}
}
void lsx_apply_blackman(double h[], const int num_points, double alpha)
{
int i, m = num_points - 1;
for (i = 0; i < num_points; ++i) {
double x = 2 * M_PI * i / m;
h[i] *= (1 - alpha) *.5 - .5 * cos(x) + alpha * .5 * cos(2 * x);
}
}
void lsx_apply_blackman_nutall(double h[], const int num_points)
{
int i, m = num_points - 1;
for (i = 0; i < num_points; ++i) {
double x = 2 * M_PI * i / m;
h[i] *= .3635819 - .4891775 * cos(x) + .1365995 * cos(2 * x) - .0106411 * cos(3 * x);
}
}
double lsx_kaiser_beta(double att)
{
if (att > 100 ) return .1117 * att - 1.11;
if (att > 50 ) return .1102 * (att - 8.7);
if (att > 20.96) return .58417 * pow(att -20.96, .4) + .07886 * (att - 20.96);
return 0;
}
void lsx_apply_kaiser(double h[], const int num_points, double beta)
{
int i, m = num_points - 1;
for (i = 0; i <= m; ++i) {
double x = 2. * i / m - 1;
h[i] *= lsx_bessel_I_0(beta * sqrt(1 - x * x)) / lsx_bessel_I_0(beta);
}
}