2134
|
1 /*
|
|
2 * copyright (c) 2005-2012 Michael Niedermayer <michaelni@gmx.at>
|
|
3 *
|
|
4 * This file is part of FFmpeg.
|
|
5 *
|
|
6 * FFmpeg is free software; you can redistribute it and/or
|
|
7 * modify it under the terms of the GNU Lesser General Public
|
|
8 * License as published by the Free Software Foundation; either
|
|
9 * version 2.1 of the License, or (at your option) any later version.
|
|
10 *
|
|
11 * FFmpeg is distributed in the hope that it will be useful,
|
|
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
14 * Lesser General Public License for more details.
|
|
15 *
|
|
16 * You should have received a copy of the GNU Lesser General Public
|
|
17 * License along with FFmpeg; if not, write to the Free Software
|
|
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
19 */
|
|
20
|
|
21 #ifndef AVUTIL_MATHEMATICS_H
|
|
22 #define AVUTIL_MATHEMATICS_H
|
|
23
|
|
24 #include <stdint.h>
|
|
25 #include <math.h>
|
|
26 #include "attributes.h"
|
|
27 #include "rational.h"
|
|
28 #include "intfloat.h"
|
|
29
|
|
30 #ifndef M_E
|
|
31 #define M_E 2.7182818284590452354 /* e */
|
|
32 #endif
|
|
33 #ifndef M_LN2
|
|
34 #define M_LN2 0.69314718055994530942 /* log_e 2 */
|
|
35 #endif
|
|
36 #ifndef M_LN10
|
|
37 #define M_LN10 2.30258509299404568402 /* log_e 10 */
|
|
38 #endif
|
|
39 #ifndef M_LOG2_10
|
|
40 #define M_LOG2_10 3.32192809488736234787 /* log_2 10 */
|
|
41 #endif
|
|
42 #ifndef M_PHI
|
|
43 #define M_PHI 1.61803398874989484820 /* phi / golden ratio */
|
|
44 #endif
|
|
45 #ifndef M_PI
|
|
46 #define M_PI 3.14159265358979323846 /* pi */
|
|
47 #endif
|
|
48 #ifndef M_SQRT1_2
|
|
49 #define M_SQRT1_2 0.70710678118654752440 /* 1/sqrt(2) */
|
|
50 #endif
|
|
51 #ifndef M_SQRT2
|
|
52 #define M_SQRT2 1.41421356237309504880 /* sqrt(2) */
|
|
53 #endif
|
|
54 #ifndef NAN
|
|
55 #define NAN av_int2float(0x7fc00000)
|
|
56 #endif
|
|
57 #ifndef INFINITY
|
|
58 #define INFINITY av_int2float(0x7f800000)
|
|
59 #endif
|
|
60
|
|
61 /**
|
|
62 * @addtogroup lavu_math
|
|
63 * @{
|
|
64 */
|
|
65
|
|
66
|
|
67 enum AVRounding {
|
|
68 AV_ROUND_ZERO = 0, ///< Round toward zero.
|
|
69 AV_ROUND_INF = 1, ///< Round away from zero.
|
|
70 AV_ROUND_DOWN = 2, ///< Round toward -infinity.
|
|
71 AV_ROUND_UP = 3, ///< Round toward +infinity.
|
|
72 AV_ROUND_NEAR_INF = 5, ///< Round to nearest and halfway cases away from zero.
|
|
73 AV_ROUND_PASS_MINMAX = 8192, ///< Flag to pass INT64_MIN/MAX through instead of rescaling, this avoids special cases for AV_NOPTS_VALUE
|
|
74 };
|
|
75
|
|
76 /**
|
|
77 * Return the greatest common divisor of a and b.
|
|
78 * If both a and b are 0 or either or both are <0 then behavior is
|
|
79 * undefined.
|
|
80 */
|
|
81 int64_t av_const av_gcd(int64_t a, int64_t b);
|
|
82
|
|
83 /**
|
|
84 * Rescale a 64-bit integer with rounding to nearest.
|
|
85 * A simple a*b/c isn't possible as it can overflow.
|
|
86 */
|
|
87 int64_t av_rescale(int64_t a, int64_t b, int64_t c) av_const;
|
|
88
|
|
89 /**
|
|
90 * Rescale a 64-bit integer with specified rounding.
|
|
91 * A simple a*b/c isn't possible as it can overflow.
|
|
92 *
|
|
93 * @return rescaled value a, or if AV_ROUND_PASS_MINMAX is set and a is
|
|
94 * INT64_MIN or INT64_MAX then a is passed through unchanged.
|
|
95 */
|
|
96 int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding) av_const;
|
|
97
|
|
98 /**
|
|
99 * Rescale a 64-bit integer by 2 rational numbers.
|
|
100 */
|
|
101 int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;
|
|
102
|
|
103 /**
|
|
104 * Rescale a 64-bit integer by 2 rational numbers with specified rounding.
|
|
105 *
|
|
106 * @return rescaled value a, or if AV_ROUND_PASS_MINMAX is set and a is
|
|
107 * INT64_MIN or INT64_MAX then a is passed through unchanged.
|
|
108 */
|
|
109 int64_t av_rescale_q_rnd(int64_t a, AVRational bq, AVRational cq,
|
|
110 enum AVRounding) av_const;
|
|
111
|
|
112 /**
|
|
113 * Compare 2 timestamps each in its own timebases.
|
|
114 * The result of the function is undefined if one of the timestamps
|
|
115 * is outside the int64_t range when represented in the others timebase.
|
|
116 * @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
|
|
117 */
|
|
118 int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b);
|
|
119
|
|
120 /**
|
|
121 * Compare 2 integers modulo mod.
|
|
122 * That is we compare integers a and b for which only the least
|
|
123 * significant log2(mod) bits are known.
|
|
124 *
|
|
125 * @param mod must be a power of 2
|
|
126 * @return a negative value if a is smaller than b
|
|
127 * a positive value if a is greater than b
|
|
128 * 0 if a equals b
|
|
129 */
|
|
130 int64_t av_compare_mod(uint64_t a, uint64_t b, uint64_t mod);
|
|
131
|
|
132 /**
|
|
133 * Rescale a timestamp while preserving known durations.
|
|
134 *
|
|
135 * @param in_ts Input timestamp
|
|
136 * @param in_tb Input timesbase
|
|
137 * @param fs_tb Duration and *last timebase
|
|
138 * @param duration duration till the next call
|
|
139 * @param out_tb Output timesbase
|
|
140 */
|
|
141 int64_t av_rescale_delta(AVRational in_tb, int64_t in_ts, AVRational fs_tb, int duration, int64_t *last, AVRational out_tb);
|
|
142
|
|
143 /**
|
|
144 * @}
|
|
145 */
|
|
146
|
|
147 #endif /* AVUTIL_MATHEMATICS_H */
|