mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
140 lines
4.2 KiB
140 lines
4.2 KiB
/* |
|
* 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_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. |
|
}; |
|
|
|
/** |
|
* 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); |
|
|
|
/** |
|
* Rescale a timestamp while preserving known durations. |
|
* |
|
* @param in_ts Input timestamp |
|
* @param in_tb Input timesbase |
|
* @param fs_tb Duration and *last timebase |
|
* @param duration duration till the next call |
|
* @param out_tb Output timesbase |
|
*/ |
|
int64_t av_rescale_delta(AVRational in_tb, int64_t in_ts, AVRational fs_tb, int duration, int64_t *last, AVRational out_tb); |
|
|
|
/** |
|
* @} |
|
*/ |
|
|
|
#endif /* AVUTIL_MATHEMATICS_H */
|
|
|