subtitles support for ffplay patch by (Ian Caulfield, imc25 : cam ac uk)
[libav.git] / libavutil / intfloat_readwrite.c
... / ...
CommitLineData
1/*
2 * portable IEEE float/double read/write functions
3 *
4 * Copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21/**
22 * @file intfloat_readwrite.c
23 * Portable IEEE float/double read/write functions.
24 */
25
26#include "common.h"
27
28double av_int2dbl(int64_t v){
29 if(v+v > 0xFFELLU<<52)
30 return 0.0/0.0;
31 return ldexp(((v&(1LL<<52)-1) + (1LL<<52)) * (v>>63|1), (v>>52&0x7FF)-1075);
32}
33
34float av_int2flt(int32_t v){
35 if(v+v > 0xFF000000U)
36 return 0.0/0.0;
37 return ldexp(((v&0x7FFFFF) + (1<<23)) * (v>>31|1), (v>>23&0xFF)-150);
38}
39
40int64_t av_dbl2int(double d){
41 int e;
42 if ( !d) return 0;
43 else if(d-d) return 0x7FF0000000000000LL + ((int64_t)(d<0)<<63) + (d!=d);
44 d= frexp(d, &e);
45 return (int64_t)(d<0)<<63 | (e+1022LL)<<52 | (int64_t)((fabs(d)-0.5)*(1LL<<53));
46}
47
48int32_t av_flt2int(float d){
49 int e;
50 if ( !d) return 0;
51 else if(d-d) return 0x7F800000 + ((d<0)<<31) + (d!=d);
52 d= frexp(d, &e);
53 return (d<0)<<31 | (e+126)<<23 | (int64_t)((fabs(d)-0.5)*(1<<24));
54}