#ifndef _AVUTIL_MATHEMATICS_H_25fbf05c_
#define _AVUTIL_MATHEMATICS_H_25fbf05c_

/*
 * This file was stolen from ffmpeg and modified for usability here.
 *  The original is
 * 
 * copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
 *
 * This version is a derivative work of that version.  It is not free
 *  software; it is licensed under the GNU Lesser General Public
 *  License version 2.1, which places nontrivial restrictions on what
 *  may be done with it.  (I'm not terribly happy about that, but for
 *  my purposes accepting LGPL-infected code is a lower price than
 *  reimplementing it all myself.)
 *
 * The LGPL v2.1 as distributed with ffmpeg is in the accompanying file
 *  `LGPL-v2.1'.
 */

#include "avutil-rational.h"
#include "avutil-attributes.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_LOG2_10
#define M_LOG2_10      3.32192809488736234787  /* log_2 10 */
#endif
#ifndef M_PHI
#define M_PHI          1.61803398874989484820   /* phi / golden ratio */
#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 M_SQRT2
#define M_SQRT2        1.41421356237309504880  /* sqrt(2) */
#endif
#ifndef NAN
#define NAN            (0.0/0.0)
#endif
#ifndef INFINITY
#define INFINITY       (1.0/0.0)
#endif

/**
 * @addtogroup lavu_math
 * @{
 */


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.
};

/**
 * Return the greatest common divisor of a and b.
 * If both a and 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);

/**
 * Rescale 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;

/**
 * Rescale 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;

/**
 * Rescale a 64-bit integer by 2 rational numbers.
 */
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;

/**
 * Rescale a 64-bit integer by 2 rational numbers with specified rounding.
 */
int64_t av_rescale_q_rnd(int64_t a, AVRational bq, AVRational cq,
                         enum AVRounding) av_const;

/**
 * Compare 2 timestamps each in its own timebases.
 * The result of the function is undefined if one of the timestamps
 * is outside the int64_t range when represented in the others timebase.
 * @return -1 if ts_a is before ts_b, 1 if ts_a is after ts_b or 0 if they represent the same position
 */
int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b);

/**
 * Compare 2 integers modulo mod.
 * That is we compare integers a and b for which only the least
 * significant log2(mod) bits are known.
 *
 * @param mod must be a power of 2
 * @return a negative value if a is smaller than b
 *         a positive value if a is greater than b
 *         0                if a equals          b
 */
int64_t av_compare_mod(uint64_t a, uint64_t b, uint64_t mod);

#endif