|
- /*
- * Atpdec
- * Copyright (c) 2003 by Thierry Leconte (F4DWV)
- *
- * $Id$
- *
- * 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 (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 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., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- */
- #include "filter.h"
-
float
- fir (float *buff, const float *coeff, const int len)
- {
-
int i;
-
double r;
-
r = 0.0;
-
for (i = 0; i < len; i++) {
-
r += buff[i] * coeff[i];
-
}
-
return r;
-
}
-
void
- iqfir (float *buff, const float *Icoeff, const float *Qcoeff, const int len,
- float *Iptr, float *Qptr)
- {
-
int i;
-
float I, Q;
-
I = Q = 0.0;
-
for (i = 0; i < len; i++) {
-
double v;
-
v = buff[i];
-
I += v * Icoeff[i];
-
Q += v * Qcoeff[i];
-
}
*Iptr = I;
-
*Qptr = Q;
-
}
float
- rsfir (float *buff, const float *coeff, const int len, const double offset,
- const double delta)
- {
-
int i;
-
double n;
-
double out;
-
out = 0.0;
-
for (i = 0, n = offset; n < len - 1; n += delta, i++) {
-
int k;
-
double alpha;
-
k = (int) n;
-
alpha = n - k;
-
out += buff[i] * (coeff[k] * (1.0 - alpha) + coeff[k + 1] * alpha);
-
}
return out;
-
}
-
double
- iir (double x, iirbuff_t * buff, const iircoeff_t * coeff)
- {
-
buff->x[4] = buff->x[3];
-
buff->x[3] = buff->x[2];
-
buff->x[2] = buff->x[1];
-
buff->x[1] = buff->x[0];
-
buff->x[0] = x / coeff->G;
-
buff->y[2] = buff->y[1];
-
buff->y[1] = buff->y[0];
-
buff->y[0] = buff->x[4]
- +coeff->x[2] * buff->x[3]
- +coeff->x[1] * buff->x[2]
- +coeff->x[0] * buff->x[1]
- +buff->x[0]
+coeff->y[1] * buff->y[2]
+coeff->y[0] * buff->y[1];
-
return (buff->y[0]);
-
}
-
-
|