complex_filters.h
/*
* SpanDSP - a series of DSP components for telephony
*
* complex_filters.h
*
* Written by Steve Underwood <steveu@coppice.org>
*
* Copyright (C) 2003 Steve Underwood
*
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 2.1,
* as published by the Free Software Foundation.
*
* 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#if !defined(_SPANDSP_COMPLEX_FILTERS_H_)
#define _SPANDSP_COMPLEX_FILTERS_H_
typedef struct filter_s filter_t;
typedef float (*filter_step_func_t)(filter_t *fi, float x);
/*! Filter state */
typedef struct
{
int nz;
int np;
filter_step_func_t fsf;
} fspec_t;
struct filter_s
{
fspec_t *fs;
float sum;
int ptr; /* Only for moving average filters */
float v[];
};
typedef struct
{
filter_t *ref;
filter_t *imf;
} cfilter_t;
#if defined(__cplusplus)
extern "C"
{
#endif
SPAN_DECLARE(filter_t *) filter_create(fspec_t *fs);
SPAN_DECLARE(void) filter_delete(filter_t *fi);
SPAN_DECLARE(float) filter_step(filter_t *fi, float x);
SPAN_DECLARE(cfilter_t *) cfilter_create(fspec_t *fs);
SPAN_DECLARE(void) cfilter_delete(cfilter_t *cfi);
SPAN_DECLARE(complexf_t) cfilter_step(cfilter_t *cfi, const complexf_t *z);
#if defined(__cplusplus)
}
#endif
#endif
/*- End of file ------------------------------------------------------------*/
cfilter_t
Definition complex_filters.h:50
complexf_t
Definition complex.h:43
filter_s
Definition complex_filters.h:42
fspec_t
Definition complex_filters.h:35