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			54 lines
		
	
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			54 lines
		
	
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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|  */
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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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|  
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| #include "common.h"
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| 
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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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| 
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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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| 
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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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| 
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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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| }
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