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/*
* Rational numbers
* Copyright (c) 2003 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
/**
* @file rational.h
* Rational numbers.
* @author Michael Niedermayer <michaelni@gmx.at>
*/
#ifndef RATIONAL_H
#define RATIONAL_H
/**
* Rational number num/den.
*/
typedef struct AVRational{
int num; ///< numerator
int den; ///< denominator
} AVRational;
/**
* returns 0 if a==b, 1 if a>b and -1 if a<b.
*/
static inline int av_cmp_q(AVRational a, AVRational b){
const int64_t tmp= a.num * (int64_t)b.den - b.num * (int64_t)a.den;
if(tmp) return (tmp>>63)|1;
else return 0;
}
/**
* converts the given AVRational to a double.
*/
static inline double av_q2d(AVRational a){
return a.num / (double) a.den;
}
/**
* reduce a fraction.
* this is usefull for framerate calculations
* @param max the maximum allowed for dst_nom & dst_den
* @return 1 if exact, 0 otherwise
*/
int av_reduce(int *dst_nom, int *dst_den, int64_t nom, int64_t den, int64_t max);
AVRational av_mul_q(AVRational b, AVRational c);
AVRational av_div_q(AVRational b, AVRational c);
AVRational av_add_q(AVRational b, AVRational c);
AVRational av_sub_q(AVRational b, AVRational c);
AVRational av_d2q(double d, int max);
#endif // RATIONAL_H
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