ref: a847d7a53d64b1f7d11eb3b969c2684ea0aa399b
dir: /sys/src/cmd/audio/libFLAC/private/float.h/
/* libFLAC - Free Lossless Audio Codec library * Copyright (C) 2004-2009 Josh Coalson * Copyright (C) 2011-2014 Xiph.Org Foundation * * 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