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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006-2007 Thom Johansen
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef _EQ_H
#define _EQ_H
#include <inttypes.h>
/* These depend on the fixed point formats used by the different filter types
and need to be changed when they change.
*/
#define FILTER_BISHELF_SHIFT 5
#define EQ_PEAK_SHIFT 4
#define EQ_SHELF_SHIFT 6
struct eqfilter {
int32_t coefs[5]; /* Order is b0, b1, b2, a1, a2 */
int32_t history[2][4];
};
void filter_shelf_coefs(unsigned long cutoff, long A, bool low, int32_t *c);
void filter_bishelf_coefs(unsigned long cutoff_low, unsigned long cutoff_high,
long A_low, long A_high, long A, int32_t *c);
void eq_pk_coefs(unsigned long cutoff, unsigned long Q, long db, int32_t *c);
void eq_ls_coefs(unsigned long cutoff, unsigned long Q, long db, int32_t *c);
void eq_hs_coefs(unsigned long cutoff, unsigned long Q, long db, int32_t *c);
void eq_filter(int32_t **x, struct eqfilter *f, unsigned num,
unsigned channels, unsigned shift);
#endif
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