99 lines
3.1 KiB
C
99 lines
3.1 KiB
C
/* SoX Resampler Library Copyright (c) 2007-12 robs@users.sourceforge.net
|
|
* Licence for this file: LGPL v2.1 See LICENCE for details. */
|
|
|
|
/* Resample using an interpolated poly-phase FIR with length LEN.*/
|
|
/* Input must be followed by LEN-1 samples. */
|
|
|
|
#define a (coef(p->shared->poly_fir_coefs, COEF_INTERP, FIR_LENGTH, phase, 0,j))
|
|
#define b (coef(p->shared->poly_fir_coefs, COEF_INTERP, FIR_LENGTH, phase, 1,j))
|
|
#define c (coef(p->shared->poly_fir_coefs, COEF_INTERP, FIR_LENGTH, phase, 2,j))
|
|
#define d (coef(p->shared->poly_fir_coefs, COEF_INTERP, FIR_LENGTH, phase, 3,j))
|
|
#if COEF_INTERP == 0
|
|
#define _ sum += a *in[j], ++j;
|
|
#elif COEF_INTERP == 1
|
|
#define _ sum += (b *x + a)*in[j], ++j;
|
|
#elif COEF_INTERP == 2
|
|
#define _ sum += ((c *x + b)*x + a)*in[j], ++j;
|
|
#elif COEF_INTERP == 3
|
|
#define _ sum += (((d*x + c)*x + b)*x + a)*in[j], ++j;
|
|
#else
|
|
#error COEF_INTERP
|
|
#endif
|
|
|
|
static void FUNCTION(stage_t * p, fifo_t * output_fifo)
|
|
{
|
|
sample_t const * input = stage_read_p(p);
|
|
int i, num_in = stage_occupancy(p), max_num_out = 1 + (int)(num_in*p->out_in_ratio);
|
|
sample_t * output = fifo_reserve(output_fifo, max_num_out);
|
|
|
|
#if defined HI_PREC_CLOCK
|
|
#if FLOAT_HI_PREC_CLOCK
|
|
if (p->use_hi_prec_clock) {
|
|
float_step_t at = p->at.flt;
|
|
for (i = 0; (int)at < num_in; ++i, at += p->step.flt) {
|
|
sample_t const * in = input + (int)at;
|
|
float_step_t frac = at - (int)at;
|
|
int phase = (int)(frac * (1 << PHASE_BITS));
|
|
#if COEF_INTERP > 0
|
|
sample_t x = (sample_t)(frac * (1 << PHASE_BITS) - phase);
|
|
#endif
|
|
sample_t sum = 0;
|
|
int j = 0;
|
|
CONVOLVE
|
|
output[i] = sum;
|
|
}
|
|
fifo_read(&p->fifo, (int)at, NULL);
|
|
p->at.flt = at - (int)at;
|
|
} else
|
|
#else
|
|
if (p->use_hi_prec_clock) {
|
|
for (i = 0; p->at.integer < num_in; ++i,
|
|
p->at.fix.ls.all += p->step.fix.ls.all,
|
|
p->at.whole += p->step.whole + (p->at.fix.ls.all < p->step.fix.ls.all)) {
|
|
sample_t const * in = input + p->at.integer;
|
|
uint32_t frac = p->at.fraction;
|
|
int phase = (int)(frac >> (32 - PHASE_BITS)); /* high-order bits */
|
|
#if COEF_INTERP > 0 /* low-order bits, scaled to [0,1) */
|
|
sample_t x = (sample_t)((frac << PHASE_BITS) * (1 / MULT32));
|
|
#endif
|
|
sample_t sum = 0;
|
|
int j = 0;
|
|
CONVOLVE
|
|
output[i] = sum;
|
|
}
|
|
fifo_read(&p->fifo, p->at.integer, NULL);
|
|
p->at.integer = 0;
|
|
} else
|
|
#endif
|
|
#endif
|
|
{
|
|
for (i = 0; p->at.integer < num_in; ++i, p->at.whole += p->step.whole) {
|
|
sample_t const * in = input + p->at.integer;
|
|
uint32_t frac = p->at.fraction;
|
|
int phase = (int)(frac >> (32 - PHASE_BITS)); /* high-order bits */
|
|
#if COEF_INTERP > 0 /* low-order bits, scaled to [0,1) */
|
|
sample_t x = (sample_t)((frac << PHASE_BITS) * (1 / MULT32));
|
|
#endif
|
|
sample_t sum = 0;
|
|
int j = 0;
|
|
CONVOLVE
|
|
output[i] = sum;
|
|
}
|
|
fifo_read(&p->fifo, p->at.integer, NULL);
|
|
p->at.integer = 0;
|
|
}
|
|
assert(max_num_out - i >= 0);
|
|
fifo_trim_by(output_fifo, max_num_out - i);
|
|
}
|
|
|
|
#undef _
|
|
#undef a
|
|
#undef b
|
|
#undef c
|
|
#undef d
|
|
#undef COEF_INTERP
|
|
#undef CONVOLVE
|
|
#undef FIR_LENGTH
|
|
#undef FUNCTION
|
|
#undef PHASE_BITS
|