/*

  * copyright (c) 2005-2012 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 "attributes.h"

 #include "rational.h"

 #include "intfloat.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_PI_2
 #define M_PI_2         1.57079632679489661923  /* pi/2 */
 #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            av_int2float(0x7fc00000)

 #endif
 #ifndef INFINITY

 #define INFINITY       av_int2float(0x7f800000)

 #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.

     AV_ROUND_PASS_MINMAX = 8192, ///< Flag to pass INT64_MIN/MAX through instead of rescaling, this avoids special cases for AV_NOPTS_VALUE

 };
 

 /**

  * Compute the greatest common divisor of a and b.
  *
  * @return gcd of a and b up to sign; if a >= 0 and b >= 0, return value is >= 0;
  * if a == 0 and b == 0, returns 0.

  */

 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.

  *

  * @return rescaled value a, or if AV_ROUND_PASS_MINMAX is set and a is
  *         INT64_MIN or INT64_MAX then a is passed through unchanged.

  */

 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.

  *

  * @return rescaled value a, or if AV_ROUND_PASS_MINMAX is set and a is
  *         INT64_MIN or INT64_MAX then a is passed through unchanged.

  */
 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);

 /**

  * Rescale a timestamp while preserving known durations.

  *
  * @param in_ts Input timestamp

  * @param in_tb Input timebase

  * @param fs_tb Duration and *last timebase
  * @param duration duration till the next call

  * @param out_tb Output timebase

  */
 int64_t av_rescale_delta(AVRational in_tb, int64_t in_ts,  AVRational fs_tb, int duration, int64_t *last, AVRational out_tb);
 
 /**

  * Add a value to a timestamp.
  *

  * This function guarantees that when the same value is repeatly added that

  * no accumulation of rounding errors occurs.
  *
  * @param ts Input timestamp
  * @param ts_tb Input timestamp timebase
  * @param inc value to add to ts
  * @param inc_tb inc timebase
  */
 int64_t av_add_stable(AVRational ts_tb, int64_t ts, AVRational inc_tb, int64_t inc);
 
 
     /**

  * @}
  */
 

 #endif /* AVUTIL_MATHEMATICS_H */