mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-30 03:12:08 +00:00
84 lines
2.5 KiB
C
84 lines
2.5 KiB
C
/*
|
|
* 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 AVUTIL_MATHEMATICS_H
|
|
#define AVUTIL_MATHEMATICS_H
|
|
|
|
#include <stdint.h>
|
|
#include <math.h>
|
|
#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
|
|
#ifndef NAN
|
|
#define NAN (0.0/0.0)
|
|
#endif
|
|
#ifndef INFINITY
|
|
#define INFINITY (1.0/0.0)
|
|
#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.
|
|
};
|
|
|
|
/**
|
|
* Returns the greatest common divisor of a and b.
|
|
* If either a or b are 0 or either or both are <0 then behavior is
|
|
* undefined.
|
|
*/
|
|
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 */
|