qzdoom/FLAC/private/float.h

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2006-04-14 12:58:52 +00:00
/* libFLAC - Free Lossless Audio Codec library
* Copyright (C) 2004,2005,2006,2007 Josh Coalson
2006-04-14 12:58:52 +00:00
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the Xiph.org Foundation nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef FLAC__PRIVATE__FLOAT_H
#define FLAC__PRIVATE__FLOAT_H
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "FLAC/ordinals.h"
/*
* These typedefs make it easier to ensure that integer versions of
* the library really only contain integer operations. All the code
* in libFLAC should use FLAC__float and FLAC__double in place of
* float and double, and be protected by checks of the macro
* FLAC__INTEGER_ONLY_LIBRARY.
*
* FLAC__real is the basic floating point type used in LPC analysis.
*/
#ifndef FLAC__INTEGER_ONLY_LIBRARY
typedef double FLAC__double;
typedef float FLAC__float;
/*
* WATCHOUT: changing FLAC__real will change the signatures of many
* functions that have assembly language equivalents and break them.
*/
typedef float FLAC__real;
#else
/*
* The convention for FLAC__fixedpoint is to use the upper 16 bits
* for the integer part and lower 16 bits for the fractional part.
*/
typedef FLAC__int32 FLAC__fixedpoint;
extern const FLAC__fixedpoint FLAC__FP_ZERO;
extern const FLAC__fixedpoint FLAC__FP_ONE_HALF;
extern const FLAC__fixedpoint FLAC__FP_ONE;
extern const FLAC__fixedpoint FLAC__FP_LN2;
extern const FLAC__fixedpoint FLAC__FP_E;
#define FLAC__fixedpoint_trunc(x) ((x)>>16)
#define FLAC__fixedpoint_mul(x, y) ( (FLAC__fixedpoint) ( ((FLAC__int64)(x)*(FLAC__int64)(y)) >> 16 ) )
#define FLAC__fixedpoint_div(x, y) ( (FLAC__fixedpoint) ( ( ((FLAC__int64)(x)<<32) / (FLAC__int64)(y) ) >> 16 ) )
/*
* FLAC__fixedpoint_log2()
* --------------------------------------------------------------------
* Returns the base-2 logarithm of the fixed-point number 'x' using an
* algorithm by Knuth for x >= 1.0
*
* 'fracbits' is the number of fractional bits of 'x'. 'fracbits' must
* be < 32 and evenly divisible by 4 (0 is OK but not very precise).
*
* 'precision' roughly limits the number of iterations that are done;
* use (unsigned)(-1) for maximum precision.
*
* If 'x' is less than one -- that is, x < (1<<fracbits) -- then this
* function will punt and return 0.
*
* The return value will also have 'fracbits' fractional bits.
*/
FLAC__uint32 FLAC__fixedpoint_log2(FLAC__uint32 x, unsigned fracbits, unsigned precision);
#endif
#endif