/* * copyright (c) 2005 Michael Niedermayer * * This file is part of FFmpeg. * * FFmpeg 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 2.1 of the License, or (at your option) any later version. * * FFmpeg 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 FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVUTIL_MATHEMATICS_H #define AVUTIL_MATHEMATICS_H #include #include #include "common.h" #include "rational.h" #ifndef M_E #define M_E 2.7182818284590452354 /* e */ #endif #ifndef M_LN2 #define M_LN2 0.69314718055994530942 /* log_e 2 */ #endif #ifndef M_LN10 #define M_LN10 2.30258509299404568402 /* log_e 10 */ #endif #ifndef M_PI #define M_PI 3.14159265358979323846 /* pi */ #endif #ifndef M_SQRT1_2 #define M_SQRT1_2 0.70710678118654752440 /* 1/sqrt(2) */ #endif enum AVRounding { AV_ROUND_ZERO = 0, ///< Round toward zero. AV_ROUND_INF = 1, ///< Round away from zero. AV_ROUND_DOWN = 2, ///< Round toward -infinity. AV_ROUND_UP = 3, ///< Round toward +infinity. AV_ROUND_NEAR_INF = 5, ///< Round to nearest and halfway cases away from zero. }; int64_t av_const av_gcd(int64_t a, int64_t b); /** * Rescales a 64-bit integer with rounding to nearest. * A simple a*b/c isn't possible as it can overflow. */ int64_t av_rescale(int64_t a, int64_t b, int64_t c) av_const; /** * Rescales a 64-bit integer with specified rounding. * A simple a*b/c isn't possible as it can overflow. */ int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding) av_const; /** * Rescales a 64-bit integer by 2 rational numbers. */ int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const; #endif /* AVUTIL_MATHEMATICS_H */