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- /* libFLAC - Free Lossless Audio Codec library
- * Copyright (C) 2004,2005,2006,2007 Josh Coalson
- *
- * 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_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
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