112 lines
2.9 KiB
C
112 lines
2.9 KiB
C
/*
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* SpanDSP - a series of DSP components for telephony
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*
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* complex_filters.c
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*
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* Written by Steve Underwood <steveu@coppice.org>
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*
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* Copyright (C) 2003 Steve Underwood
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*
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* All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License version 2.1,
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* as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#if defined(HAVE_CONFIG_H)
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#include "config.h"
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#endif
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#include <stdlib.h>
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#include <stdio.h>
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#include <inttypes.h>
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#include "spandsp/telephony.h"
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#include "spandsp/alloc.h"
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#include "spandsp/complex.h"
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#include "spandsp/complex_filters.h"
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SPAN_DECLARE(filter_t *) filter_create(fspec_t *fs)
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{
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int i;
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filter_t *fi;
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if ((fi = (filter_t *) span_alloc(sizeof(*fi) + sizeof(float)*(fs->np + 1))))
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{
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fi->fs = fs;
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fi->sum = 0.0;
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/* Moving average filters only */
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fi->ptr = 0;
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for (i = 0; i <= fi->fs->np; i++)
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fi->v[i] = 0.0;
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}
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return fi;
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}
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/*- End of function --------------------------------------------------------*/
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SPAN_DECLARE(void) filter_delete(filter_t *fi)
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{
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if (fi)
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span_free(fi);
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}
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/*- End of function --------------------------------------------------------*/
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SPAN_DECLARE(float) filter_step(filter_t *fi, float x)
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{
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return fi->fs->fsf(fi, x);
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}
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/*- End of function --------------------------------------------------------*/
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SPAN_DECLARE(cfilter_t *) cfilter_create(fspec_t *fs)
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{
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cfilter_t *cfi;
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if ((cfi = (cfilter_t *) span_alloc(sizeof(*cfi))))
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{
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if ((cfi->ref = filter_create(fs)) == NULL)
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{
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span_free(cfi);
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return NULL;
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}
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if ((cfi->imf = filter_create(fs)) == NULL)
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{
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span_free(cfi->ref);
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span_free(cfi);
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return NULL;
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}
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}
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return cfi;
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}
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/*- End of function --------------------------------------------------------*/
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SPAN_DECLARE(void) cfilter_delete(cfilter_t *cfi)
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{
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if (cfi)
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{
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filter_delete(cfi->ref);
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filter_delete(cfi->imf);
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}
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}
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/*- End of function --------------------------------------------------------*/
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SPAN_DECLARE(complexf_t) cfilter_step(cfilter_t *cfi, const complexf_t *z)
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{
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complexf_t cc;
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cc.re = filter_step(cfi->ref, z->re);
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cc.im = filter_step(cfi->imf, z->im);
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return cc;
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}
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/*- End of function --------------------------------------------------------*/
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/*- End of file ------------------------------------------------------------*/
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