gst_plugins_base/gst/audioresample/functable.c
branchRCL_3
changeset 30 7e817e7e631c
parent 0 0e761a78d257
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gst_plugins_base/gst/audioresample/functable.c	Wed Sep 01 12:16:41 2010 +0100
@@ -0,0 +1,309 @@
+/* Resampling library
+ * Copyright (C) <2001> David A. Schleef <ds@schleef.org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#ifndef __SYMBIAN32__
+#include <config.h>
+#else
+#include "config.h"
+#endif
+#endif
+
+#include <string.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "functable.h"
+#include "debug.h"
+
+
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+functable_func_sinc (double *fx, double *dfx, double x, void *closure)
+{
+  if (x == 0) {
+    *fx = 1;
+    *dfx = 0;
+    return;
+  }
+
+  *fx = sin (x) / x;
+  *dfx = (cos (x) - sin (x) / x) / x;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+functable_func_boxcar (double *fx, double *dfx, double x, void *closure)
+{
+  double width = *(double *) closure;
+
+  if (x < width && x > -width) {
+    *fx = 1;
+  } else {
+    *fx = 0;
+  }
+  *dfx = 0;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+functable_func_hanning (double *fx, double *dfx, double x, void *closure)
+{
+  double width = *(double *) closure;
+
+  if (x < width && x > -width) {
+    x /= width;
+    *fx = (1 - x * x) * (1 - x * x);
+    *dfx = -2 * 2 * x / width * (1 - x * x);
+  } else {
+    *fx = 0;
+    *dfx = 0;
+  }
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+
+Functable *
+functable_new (void)
+{
+  Functable *ft;
+
+  ft = malloc (sizeof (Functable));
+  memset (ft, 0, sizeof (Functable));
+
+  return ft;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+functable_free (Functable * ft)
+{
+  free (ft);
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+functable_set_length (Functable * t, int length)
+{
+  t->length = length;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+functable_set_offset (Functable * t, double offset)
+{
+  t->offset = offset;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+functable_set_multiplier (Functable * t, double multiplier)
+{
+  t->multiplier = multiplier;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+functable_calculate (Functable * t, FunctableFunc func, void *closure)
+{
+  int i;
+  double x;
+
+  if (t->fx)
+    free (t->fx);
+  if (t->dfx)
+    free (t->dfx);
+
+  t->fx = malloc (sizeof (double) * (t->length + 1));
+  t->dfx = malloc (sizeof (double) * (t->length + 1));
+
+  t->inv_multiplier = 1.0 / t->multiplier;
+
+  for (i = 0; i < t->length + 1; i++) {
+    x = t->offset + t->multiplier * i;
+
+    func (&t->fx[i], &t->dfx[i], x, closure);
+  }
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+functable_calculate_multiply (Functable * t, FunctableFunc func, void *closure)
+{
+  int i;
+  double x;
+
+  for (i = 0; i < t->length + 1; i++) {
+    double afx, adfx, bfx, bdfx;
+
+    afx = t->fx[i];
+    adfx = t->dfx[i];
+    x = t->offset + t->multiplier * i;
+    func (&bfx, &bdfx, x, closure);
+    t->fx[i] = afx * bfx;
+    t->dfx[i] = afx * bdfx + adfx * bfx;
+  }
+
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+double
+functable_evaluate (Functable * t, double x)
+{
+  int i;
+  double f0, f1, w0, w1;
+  double x2, x3;
+  double w;
+
+  if (x < t->offset || x > (t->offset + t->length * t->multiplier)) {
+    RESAMPLE_DEBUG ("x out of range %g", x);
+  }
+
+  x -= t->offset;
+  x *= t->inv_multiplier;
+  i = floor (x);
+  x -= i;
+
+  x2 = x * x;
+  x3 = x2 * x;
+
+  f1 = 3 * x2 - 2 * x3;
+  f0 = 1 - f1;
+  w0 = (x - 2 * x2 + x3) * t->multiplier;
+  w1 = (-x2 + x3) * t->multiplier;
+
+  w = t->fx[i] * f0 + t->fx[i + 1] * f1 + t->dfx[i] * w0 + t->dfx[i + 1] * w1;
+
+  /*w = t->fx[i] * (1-x) + t->fx[i+1] * x; */
+
+  return w;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+
+double
+functable_fir (Functable * t, double x, int n, double *data, int len)
+{
+  int i, j;
+  double f0, f1, w0, w1;
+  double x2, x3;
+  double w;
+  double sum;
+
+  x -= t->offset;
+  x /= t->multiplier;
+  i = floor (x);
+  x -= i;
+
+  x2 = x * x;
+  x3 = x2 * x;
+
+  f1 = 3 * x2 - 2 * x3;
+  f0 = 1 - f1;
+  w0 = (x - 2 * x2 + x3) * t->multiplier;
+  w1 = (-x2 + x3) * t->multiplier;
+
+  sum = 0;
+  for (j = 0; j < len; j++) {
+    w = t->fx[i] * f0 + t->fx[i + 1] * f1 + t->dfx[i] * w0 + t->dfx[i + 1] * w1;
+    sum += data[j * 2] * w;
+    i += n;
+  }
+
+  return sum;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+functable_fir2 (Functable * t, double *r0, double *r1, double x,
+    int n, double *data, int len)
+{
+  int i, j;
+  double f0, f1, w0, w1;
+  double x2, x3;
+  double w;
+  double sum0, sum1;
+  double floor_x;
+
+  x -= t->offset;
+  x *= t->inv_multiplier;
+  floor_x = floor (x);
+  i = floor_x;
+  x -= floor_x;
+
+  x2 = x * x;
+  x3 = x2 * x;
+
+  f1 = 3 * x2 - 2 * x3;
+  f0 = 1 - f1;
+  w0 = (x - 2 * x2 + x3) * t->multiplier;
+  w1 = (-x2 + x3) * t->multiplier;
+
+  sum0 = 0;
+  sum1 = 0;
+  for (j = 0; j < len; j++) {
+    w = t->fx[i] * f0 + t->fx[i + 1] * f1 + t->dfx[i] * w0 + t->dfx[i + 1] * w1;
+    sum0 += data[j * 2] * w;
+    sum1 += data[j * 2 + 1] * w;
+    i += n;
+  }
+
+  *r0 = sum0;
+  *r1 = sum1;
+}