rockbox/apps/eq.h
Thom Johansen 7df51ada07 Changed meaning of shift parameter to include the EMAC implicit shift
factor. ARM version is already fixed.


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@8520 a1c6a512-1295-4272-9138-f99709370657
2006-02-01 09:48:47 +00:00

41 lines
1.5 KiB
C

/***************************************************************************
* __________ __ ___.
* 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
/* 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 8
struct eqfilter {
long coefs[5]; /* Order is b0, b1, b2, a1, a2 */
long history[2][4];
};
void eq_pk_coefs(unsigned long cutoff, unsigned long Q, long db, long *c);
void eq_ls_coefs(unsigned long cutoff, unsigned long Q, long db, long *c);
void eq_hs_coefs(unsigned long cutoff, unsigned long Q, long db, long *c);
void eq_filter(long **x, struct eqfilter *f, unsigned num,
unsigned channels, unsigned shift);
#endif