/* * 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 FFMPEG_MATHEMATICS_H #define FFMPEG_MATHEMATICS_H #include #include "rational.h" 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 }; /** * rescale a 64bit 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); /** * rescale a 64bit 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); /** * rescale a 64bit integer by 2 rational numbers. */ int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq); #endif /* FFMPEG_MATHEMATICS_H */