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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 Jens Arnold
*
* Fixed point library for plugins
*
* 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.
*
****************************************************************************/
/** APPS - FIXED POINT MATH ROUTINES - USAGE
*
* - x and y arguments are fixed point integers
* - fracbits is the number of fractional bits in the argument(s)
* - functions return long fixed point integers with the specified number
* of fractional bits unless otherwise specified
*
* Multiply two fixed point numbers:
* fp_mul(x, y, fracbits)
*
* Divide two fixed point numbers:
* fp_div(x, y, fracbits)
*
* Calculate decibel equivalent of a gain factor:
* fp_decibels(factor, fracbits)
* where fracbits is in the range 12 to 22 (higher is better),
* and factor is a positive fixed point integer.
*
* Calculate factor equivalent of a decibel value:
* fp_factor(decibels, fracbits)
* where fracbits is in the range 12 to 22 (lower is better),
* and decibels is a fixed point integer.
*/
#ifndef _FIXEDPOINT_H_APPS
#define _FIXEDPOINT_H_APPS
#define fp_mul(x, y, z) (long)((((long long)(x)) * ((long long)(y))) >> (z))
#define fp_div(x, y, z) (long)((((long long)(x)) << (z)) / ((long long)(y)))
/** TAKEN FROM ORIGINAL fixedpoint.h */
long fp_sincos(unsigned long phase, long *cos);
/** MODIFIED FROM replaygain.c */
#define FP_INF (0x7fffffff)
#define FP_NEGINF -(0x7fffffff)
/* fracbits in range 12 - 22 work well. Higher is better for
* calculating dB, lower is better for calculating factor.
*/
/* long fp_decibels(unsigned long factor, unsigned int fracbits); */
long fp_factor(long decibels, unsigned int fracbits);
#endif
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