ffmpeg / libavutil / integer.h @ bfe3676f
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/*


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* arbitrary precision integers

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* Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>

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*

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* This file is part of FFmpeg.

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*

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* FFmpeg 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 2.1 of the License, or (at your option) any later version.

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*

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* FFmpeg 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 FFmpeg; if not, write to the Free Software

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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 021101301 USA

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*/

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/**

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* @file integer.h

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* arbitrary precision integers

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* @author Michael Niedermayer <michaelni@gmx.at>

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*/

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#ifndef AVUTIL_INTEGER_H

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#define AVUTIL_INTEGER_H

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#include <stdint.h> 
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#include "common.h" 
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#define AV_INTEGER_SIZE 8 
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typedef struct AVInteger{ 
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uint16_t v[AV_INTEGER_SIZE]; 
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} AVInteger; 
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AVInteger av_add_i(AVInteger a, AVInteger b) av_const; 
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AVInteger av_sub_i(AVInteger a, AVInteger b) av_const; 
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/**

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* returns the rounded down value of the logarithm of base 2 of the given AVInteger.

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* this is simply the index of the most significant bit which is 1. Or 0 of all bits are 0

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*/

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int av_log2_i(AVInteger a) av_const;

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AVInteger av_mul_i(AVInteger a, AVInteger b) av_const; 
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/**

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* Returns 0 if a==b, 1 if a>b and 1 if a<b.

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*/

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int av_cmp_i(AVInteger a, AVInteger b) av_const;

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/**

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* bitwise shift

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* @param s the number of bits by which the value should be shifted right,

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may be negative for shifting left

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*/

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AVInteger av_shr_i(AVInteger a, int s) av_const;

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/**

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* Returns a % b.

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* @param quot a/b will be stored here.

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*/

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AVInteger av_mod_i(AVInteger *quot, AVInteger a, AVInteger b); 
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/**

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* Returns a/b.

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*/

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AVInteger av_div_i(AVInteger a, AVInteger b) av_const; 
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/**

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* Converts the given int64_t to an AVInteger.

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*/

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AVInteger av_int2i(int64_t a) av_const; 
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/**

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* Converts the given AVInteger to an int64_t.

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* If the AVInteger is too large to fit into an int64_t,

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* then only the least significant 64 bits will be used.

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*/

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int64_t av_i2int(AVInteger a) av_const; 
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#endif /* AVUTIL_INTEGER_H */ 