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livetrax/libs/zita-resampler/vmresampler.cc

240 lines
4.5 KiB
C++

// ----------------------------------------------------------------------------
//
// Copyright (C) 2006-2013 Fons Adriaensen <fons@linuxaudio.org>
// Copyright (C) 2017 Robin Gareus <robin@gareus.org>
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
//
// This program 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include "zita-resampler/vmresampler.h"
using namespace ArdourZita;
VMResampler::VMResampler (void)
: _table (0)
, _buff (0)
, _c1 (0)
, _c2 (0)
{
reset ();
}
VMResampler::~VMResampler (void)
{
clear ();
}
int
VMResampler::setup (unsigned int hlen)
{
if ((hlen < 8) || (hlen > 96)) return 1;
return setup (hlen, 1.0 - 2.6 / hlen);
}
int
VMResampler::setup (unsigned int hlen, double frel)
{
unsigned int h, k, n;
double s;
Resampler_table *T = 0;
n = NPHASE;
s = n;
h = hlen;
k = 250;
T = Resampler_table::create (frel, h, n);
clear ();
if (T) {
_table = T;
_buff = new float [2 * h - 1 + k];
_c1 = new float [2 * h];
_c2 = new float [2 * h];
_inmax = k;
_pstep = s;
_qstep = s;
_wstep = 1;
return reset ();
}
else return 1;
}
void
VMResampler::clear (void)
{
Resampler_table::destroy (_table);
delete[] _buff;
delete[] _c1;
delete[] _c2;
_buff = 0;
_c1 = 0;
_c2 = 0;
_table = 0;
_inmax = 0;
_pstep = 0;
_qstep = 0;
_wstep = 1;
reset ();
}
void
VMResampler::set_phase (double p)
{
if (!_table) return;
_phase = (p - floor (p)) * _table->_np;
}
void
VMResampler::set_rrfilt (double t)
{
if (!_table) return;
_wstep = (t < 1) ? 1 : 1 - exp (-1 / t);
}
double
VMResampler::set_rratio (double r)
{
if (!_table) return 0;
if (r > 16.0) r = 16.0;
if (r < 0.02) r = 0.02;
_qstep = _table->_np / r;
if (_qstep < 4.) {
_qstep = 4.;
}
if (_qstep > 2. * _table->_np * _table->_hl) {
_qstep = 2. * _table->_np * _table->_hl;
}
return _table->_np / _qstep;
}
double
VMResampler::inpdist (void) const
{
if (!_table) return 0;
return (int)(_table->_hl + 1 - _nread) - _phase / _table->_np;
}
int
VMResampler::inpsize (void) const
{
if (!_table) return 0;
return 2 * _table->_hl;
}
int
VMResampler::reset (void)
{
if (!_table) return 1;
inp_count = 0;
out_count = 0;
inp_data = 0;
out_data = 0;
_index = 0;
_phase = 0;
_nread = 2 * _table->_hl;
memset (_buff, 0, sizeof(float) * (_nread + 249));
_nread -= _table->_hl - 1;
return 0;
}
int
VMResampler::process (void)
{
unsigned int in, nr, n;
double ph, dp;
float a, *p1, *p2;
if (!_table) return 1;
const int hl = _table->_hl;
const unsigned int np = _table->_np;
in = _index;
nr = _nread;
ph = _phase;
dp = _pstep;
n = 2 * hl - nr;
p1 = _buff + in;
p2 = p1 + n;
while (out_count) {
if (nr) {
if (inp_count == 0) break;
*p2 = *inp_data;
inp_data++;
nr--;
p2++;
inp_count--;
} else {
if (dp == np) {
const unsigned int k = (unsigned int) /*floor (ph / np) +*/ hl;
*out_data++ = p1[k];
} else {
const unsigned int k = (unsigned int) ph;
const float bb = (float)(ph - k);
const float aa = 1.0f - bb;
float const* cq1 = _table->_ctab + hl * k;
float const* cq2 = _table->_ctab + hl * (np - k);
for (int i = 0; i < hl; i++) {
_c1 [i] = aa * cq1 [i] + bb * cq1 [i + hl];
_c2 [i] = aa * cq2 [i] + bb * cq2 [i - hl];
}
a = 1e-25f;
for (int i = 0; i < hl; i++) {
a += p1[i] * _c1 [i] + p2[-i-1] * _c2 [i];
}
*out_data++ = a - 1e-25f;
}
out_count--;
const double dd = _qstep - dp;
if (fabs (dd) < 1e-12) {
dp = _qstep;
} else {
dp += _wstep * dd;
}
ph += dp;
if (ph >= np) {
nr = (unsigned int) floor (ph / np);
ph -= nr * np;
in += nr;
p1 += nr;
if (in >= _inmax) {
n = (2 * hl - nr);
memcpy (_buff, p1, n * sizeof (float));
in = 0;
p1 = _buff;
p2 = p1 + n;
}
}
}
}
_index = in;
_nread = nr;
_phase = ph;
_pstep = dp;
return 0;
}