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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 Thom Johansen
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* 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 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_bishelf_coefs(unsigned long cutoff, long ad, long an, 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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