kopia lustrzana https://github.com/Dsplib/libdspl-2.0
66 wiersze
1.7 KiB
C
66 wiersze
1.7 KiB
C
/*
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* Copyright (c) 2015-2019 Sergey Bakhurin
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* Digital Signal Processing Library [http://dsplib.org]
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*
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* This file is part of libdspl-2.0.
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*
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* 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 as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* DSPL 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 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 License
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* along with Foobar. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "dspl.h"
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#include "dspl_internal.h"
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/******************************************************************************
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* Linear phase lowpass filter
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******************************************************************************/
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int fir_linphase_lpf(int ord, double wp, int win_type,
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double win_param, double* h)
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{
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int n, err = RES_OK;
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double *w = NULL;
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w = (double*)malloc((ord+1)*sizeof(double));
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err = linspace(-(double)ord*0.5, (double)ord*0.5, ord+1, DSPL_SYMMETRIC, w);
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if(err!=RES_OK)
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goto error_proc;
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err = sinc(w, ord+1, M_PI*wp, h);
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if(err!=RES_OK)
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goto error_proc;
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err = window(w, ord+1, win_type | DSPL_SYMMETRIC, win_param);
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if(err!=RES_OK)
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goto error_proc;
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for(n = 0; n < ord+1; n++)
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h[n] *= w[n] * wp;
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error_proc:
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if(w)
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free(w);
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return err;
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}
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