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/*
* copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
*
* 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 <stdint.h>
#include <math.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_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
};
/**
* 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) av_const;
/**
* 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) av_const;
/**
* rescale a 64bit integer by 2 rational numbers.
*/
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;
#endif /* FFMPEG_MATHEMATICS_H */
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