aarch64: Add assembly support for -fsanitize=hwaddress tagged globals.
[libav.git] / libavutil / mathematics.h
1 /*
2 * copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
3 *
4 * This file is part of Libav.
5 *
6 * Libav 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 * Libav 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 Libav; 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_LOG2_10
31 #define M_LOG2_10 3.32192809488736234787 /* log_2 10 */
32 #endif
33 #ifndef M_PHI
34 #define M_PHI 1.61803398874989484820 /* phi / golden ratio */
35 #endif
36 #ifndef NAN
37 #define NAN av_int2float(0x7fc00000)
38 #endif
39 #ifndef INFINITY
40 #define INFINITY av_int2float(0x7f800000)
41 #endif
42
43 /**
44 * @addtogroup lavu_math
45 * @{
46 */
47
48
49 enum AVRounding {
50 AV_ROUND_ZERO = 0, ///< Round toward zero.
51 AV_ROUND_INF = 1, ///< Round away from zero.
52 AV_ROUND_DOWN = 2, ///< Round toward -infinity.
53 AV_ROUND_UP = 3, ///< Round toward +infinity.
54 AV_ROUND_NEAR_INF = 5, ///< Round to nearest and halfway cases away from zero.
55 };
56
57 /**
58 * Return the greatest common divisor of a and b.
59 * If both a and b are 0 or either or both are <0 then behavior is
60 * undefined.
61 */
62 int64_t av_const av_gcd(int64_t a, int64_t b);
63
64 /**
65 * Rescale a 64-bit integer with rounding to nearest.
66 * A simple a*b/c isn't possible as it can overflow.
67 */
68 int64_t av_rescale(int64_t a, int64_t b, int64_t c) av_const;
69
70 /**
71 * Rescale a 64-bit integer with specified rounding.
72 * A simple a*b/c isn't possible as it can overflow.
73 */
74 int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding) av_const;
75
76 /**
77 * Rescale a 64-bit integer by 2 rational numbers.
78 */
79 int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const;
80
81 /**
82 * Rescale a 64-bit integer by 2 rational numbers with specified rounding.
83 */
84 int64_t av_rescale_q_rnd(int64_t a, AVRational bq, AVRational cq,
85 enum AVRounding) av_const;
86
87 /**
88 * Compare 2 timestamps each in its own timebases.
89 * The result of the function is undefined if one of the timestamps
90 * is outside the int64_t range when represented in the others timebase.
91 * @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
92 */
93 int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b);
94
95 /**
96 * Compare 2 integers modulo mod.
97 * That is we compare integers a and b for which only the least
98 * significant log2(mod) bits are known.
99 *
100 * @param mod must be a power of 2
101 * @return a negative value if a is smaller than b
102 * a positive value if a is greater than b
103 * 0 if a equals b
104 */
105 int64_t av_compare_mod(uint64_t a, uint64_t b, uint64_t mod);
106
107 /**
108 * @}
109 */
110
111 #endif /* AVUTIL_MATHEMATICS_H */