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27 #ifndef AVUTIL_MATHEMATICS_H
28 #define AVUTIL_MATHEMATICS_H
37 #define M_E 2.7182818284590452354
40 #define M_Ef 2.7182818284590452354f
43 #define M_LN2 0.69314718055994530942
46 #define M_LN2f 0.69314718055994530942f
49 #define M_LN10 2.30258509299404568402
52 #define M_LN10f 2.30258509299404568402f
55 #define M_LOG2_10 3.32192809488736234787
58 #define M_LOG2_10f 3.32192809488736234787f
61 #define M_PHI 1.61803398874989484820
64 #define M_PHIf 1.61803398874989484820f
67 #define M_PI 3.14159265358979323846
70 #define M_PIf 3.14159265358979323846f
73 #define M_PI_2 1.57079632679489661923
76 #define M_PI_2f 1.57079632679489661923f
79 #define M_PI_4 0.78539816339744830962
82 #define M_PI_4f 0.78539816339744830962f
85 #define M_1_PI 0.31830988618379067154
88 #define M_1_PIf 0.31830988618379067154f
91 #define M_2_PI 0.63661977236758134308
94 #define M_2_PIf 0.63661977236758134308f
97 #define M_2_SQRTPI 1.12837916709551257390
100 #define M_2_SQRTPIf 1.12837916709551257390f
103 #define M_SQRT1_2 0.70710678118654752440
106 #define M_SQRT1_2f 0.70710678118654752440f
109 #define M_SQRT2 1.41421356237309504880
112 #define M_SQRT2f 1.41421356237309504880f
115 #define NAN av_int2float(0x7fc00000)
118 #define INFINITY av_int2float(0x7f800000)
@ AV_ROUND_UP
Round toward +infinity.
int av_compare_ts(int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b)
Compare two timestamps each in its own time base.
int64_t av_add_stable(AVRational ts_tb, int64_t ts, AVRational inc_tb, int64_t inc)
Add a value to a timestamp.
double av_bessel_i0(double x)
0th order modified bessel function of the first kind.
@ AV_ROUND_ZERO
Round toward zero.
AVRounding
Rounding methods.
int64_t av_const av_gcd(int64_t a, int64_t b)
Compute the greatest common divisor of two integer operands.
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const
Rescale a 64-bit integer by 2 rational numbers.
@ AV_ROUND_NEAR_INF
Round to nearest and halfway cases away from zero.
@ AV_ROUND_PASS_MINMAX
Flag telling rescaling functions to pass INT64_MIN/MAX through unchanged, avoiding special cases for ...
int64_t av_rescale_delta(AVRational in_tb, int64_t in_ts, AVRational fs_tb, int duration, int64_t *last, AVRational out_tb)
Rescale a timestamp while preserving known durations.
Rational number (pair of numerator and denominator).
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
static int inc(int num, int period)
@ AV_ROUND_DOWN
Round toward -infinity.
int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding rnd) av_const
Rescale a 64-bit integer with specified rounding.
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
@ AV_ROUND_INF
Round away from zero.
int64_t av_rescale(int64_t a, int64_t b, int64_t c) av_const
Rescale a 64-bit integer with rounding to nearest.
static int mod(int a, int b)
Modulo operation with only positive remainders.
int64_t av_compare_mod(uint64_t a, uint64_t b, uint64_t mod)
Compare the remainders of two integer operands divided by a common divisor.
int64_t av_rescale_q_rnd(int64_t a, AVRational bq, AVRational cq, enum AVRounding rnd) av_const
Rescale a 64-bit integer by 2 rational numbers with specified rounding.