intfloat_readwrite.c
资源名称:tcpmp.rar [点击查看]
上传用户:wstnjxml
上传日期:2014-04-03
资源大小:7248k
文件大小:2k
源码类别:
Windows CE
开发平台:
C/C++
- /*
- * portable IEEE float/double read/write functions
- *
- * Copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
- /**
- * @file intfloat_readwrite.c
- * Portable IEEE float/double read/write functions.
- */
- #include "common.h"
- double av_int2dbl(int64_t v){
- if(v+v > 0xFFELLU<<52)
- return 0.0/0.0;
- return ldexp(((v&((1LL<<52)-1)) + (1LL<<52)) * (v>>63|1), (v>>52&0x7FF)-1075);
- }
- float av_int2flt(int32_t v){
- if(v+v > 0xFF000000U)
- return 0.0/0.0;
- return ldexp(((v&0x7FFFFF) + (1<<23)) * (v>>31|1), (v>>23&0xFF)-150);
- }
- int64_t av_dbl2int(double d){
- int e;
- if ( !d) return 0;
- else if(d-d) return 0x7FF0000000000000LL + ((int64_t)(d<0)<<63) + (d!=d);
- d= frexp(d, &e);
- return (int64_t)(d<0)<<63 | (e+1022LL)<<52 | (int64_t)((fabs(d)-0.5)*(1LL<<53));
- }
- int32_t av_flt2int(float d){
- int e;
- if ( !d) return 0;
- else if(d-d) return 0x7F800000 + ((d<0)<<31) + (d!=d);
- d= frexp(d, &e);
- return (d<0)<<31 | (e+126)<<23 | (int64_t)((fabs(d)-0.5)*(1<<24));
- }