ffmpeg / libavutil / intfloat_readwrite.c @ 5509bffa
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/*
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* portable IEEE float/double read/write functions
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*
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* Copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/**
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* @file intfloat_readwrite.c
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* Portable IEEE float/double read/write functions.
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*/
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#include "common.h" |
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double av_int2dbl(int64_t v){
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if(v+v > 0xFFELLU<<52) |
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return 0.0/0.0; |
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return ldexp(((v&((1LL<<52)-1)) + (1LL<<52)) * (v>>63|1), (v>>52&0x7FF)-1075); |
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} |
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float av_int2flt(int32_t v){
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if(v+v > 0xFF000000U) |
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return 0.0/0.0; |
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return ldexp(((v&0x7FFFFF) + (1<<23)) * (v>>31|1), (v>>23&0xFF)-150); |
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} |
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int64_t av_dbl2int(double d){
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int e;
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if ( !d) return 0; |
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else if(d-d) return 0x7FF0000000000000LL + ((int64_t)(d<0)<<63) + (d!=d); |
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d= frexp(d, &e); |
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return (int64_t)(d<0)<<63 | (e+1022LL)<<52 | (int64_t)((fabs(d)-0.5)*(1LL<<53)); |
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} |
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int32_t av_flt2int(float d){
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int e;
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if ( !d) return 0; |
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else if(d-d) return 0x7F800000 + ((d<0)<<31) + (d!=d); |
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d= frexp(d, &e); |
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return (d<0)<<31 | (e+126)<<23 | (int64_t)((fabs(d)-0.5)*(1<<24)); |
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} |