/* * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ /** * @file rational.c * Rational numbers * @author Michael Niedermayer <michaelni@gmx.at> */ //#include <math.h> #include <limits.h> #include "common.h" #include "avcodec.h" #include "rational.h" AVRational av_mul_q(AVRational b, AVRational c){ av_reduce(&b.num, &b.den, b.num * (int64_t)c.num, b.den * (int64_t)c.den, INT_MAX); return b; } AVRational av_div_q(AVRational b, AVRational c){ av_reduce(&b.num, &b.den, b.num * (int64_t)c.den, b.den * (int64_t)c.num, INT_MAX); return b; } AVRational av_add_q(AVRational b, AVRational c){ av_reduce(&b.num, &b.den, b.num * (int64_t)c.den + c.num * (int64_t)b.den, b.den * (int64_t)c.den, INT_MAX); return b; } AVRational av_sub_q(AVRational b, AVRational c){ av_reduce(&b.num, &b.den, b.num * (int64_t)c.den - c.num * (int64_t)b.den, b.den * (int64_t)c.den, INT_MAX); return b; } /** * Converts a double precission floating point number to a AVRational. * @param max the maximum allowed numerator and denominator */ AVRational av_d2q(double d, int max){ AVRational a; int exponent= FFMAX( (int)(log(ABS(d) + 1e-20)/log(2)), 0); int64_t den= 1LL << (61 - exponent); av_reduce(&a.num, &a.den, (int64_t)(d * den + 0.5), den, max); return a; }