Add libzita-resampler as lib

This simplifies x-compiling and x-platform builds as well
allows to statically link, if needed.

1 files changed, 177 insertions, 0 deletions

diff --git a/libs/zita-resampler/cresampler.cc b/libs/zita-resampler/cresampler.cc
new file mode 100644
index 0000000000..2bac33a7eb
--- /dev/null
+++ b/libs/zita-resampler/cresampler.cc
@@ -0,0 +1,177 @@
+// ----------------------------------------------------------------------------
+//
+//  Copyright (C) 2013 Fons Adriaensen <fons@linuxaudio.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/cresampler.h"
+
+using namespace ArdourZita;
+
+CResampler::CResampler (void)
+	: _nchan (0)
+	, _buff  (0)
+{
+	reset ();
+}
+
+CResampler::~CResampler (void)
+{
+	clear ();
+}
+
+int
+CResampler::setup (double       ratio,
+                   unsigned int nchan)
+{
+	if (! nchan) return 1;
+	clear ();
+	_inmax = 50;
+	_buff = new float [nchan * (3 + _inmax)];
+	_nchan = nchan;
+	_pstep = 1 / ratio;
+	return reset ();
+}
+
+void
+CResampler::clear (void)
+{
+	delete[] _buff;
+	_buff  = 0;
+	_nchan = 0;
+	_inmax = 0;
+	_pstep = 0;
+	reset ();
+}
+
+void
+CResampler::set_phase (double p)
+{
+	_phase = p - floor (p);
+}
+
+void
+CResampler::set_ratio (double r)
+{
+	_pstep = 1.0 / r;
+}
+
+double
+CResampler::inpdist (void) const
+{
+	return (int)(3 - _nread) - _phase;
+}
+
+int
+CResampler::inpsize (void) const
+{
+	return 4;
+}
+
+int
+CResampler::reset (void)
+{
+	inp_count = 0;
+	out_count = 0;
+	inp_data = 0;
+	out_data = 0;
+	_index = 0;
+	_phase = 0;
+	_nread = 4;
+	_nzero = 0;
+	return 0;
+}
+
+int
+CResampler::process (void)
+{
+	unsigned int   in, nr, n, c;
+	int            nz;
+	double         ph;
+	float          *pb, a, b, d, m0, m1, m2, m3;
+
+	in = _index;
+	nr = _nread;
+	nz = _nzero;
+	ph = _phase;
+	pb = _buff + in * _nchan;
+
+	while (out_count) {
+		if (nr) {
+			if (inp_count == 0) break;
+			n = (4 - nr) * _nchan;
+			if (inp_data) {
+				for (c = 0; c < _nchan; c++) pb [n + c] = inp_data [c];
+				inp_data += _nchan;
+				nz = 0;
+			} else {
+				for (c = 0; c < _nchan; c++) pb [n + c] = 0;
+				if (nz < 4) nz++;
+			}
+			nr--;
+			inp_count--;
+		} else {
+			n = _nchan;
+			if (out_data) {
+				if (nz < 4) {
+					a = ph;
+					b = 1 - a;
+					d = a * b / 2;
+					m0 = -d * b;
+					m1 = b + (3 * b - 1) * d;
+					m2 = a + (3 * a - 1) * d;
+					m3 = -d * a;
+					for (c = 0; c < n; c++) {
+						*out_data++ = m0 * pb [0]
+							+ m1 * pb [n]
+							+ m2 * pb [2 * n]
+							+ m3 * pb [3 * n];
+						pb++;
+					}
+					pb -= n;
+				} else {
+					for (c = 0; c < n; c++) *out_data++ = 0;
+				}
+			}
+			out_count--;
+
+			ph += _pstep;
+			if (ph >= 1.0) {
+				nr = (unsigned int) floor (ph);
+				ph -= nr;
+				in += nr;
+				pb += nr * _nchan;
+				if (in >= _inmax) {
+					memcpy (_buff, pb, (4 - nr) * _nchan * sizeof (float));
+					in = 0;
+					pb = _buff;
+				}
+			}
+		}
+	}
+
+	_index = in;
+	_nread = nr;
+	_nzero = nz;
+	_phase = ph;
+
+	return 0;
+}