mathematics.c File Reference

miscellaneous math routines and tables More...

#include <stdint.h>
#include <limits.h>
#include "mathematics.h"
#include "libavutil/common.h"
#include "avassert.h"
#include "version.h"

Go to the source code of this file.

Functions
int64_t	av_gcd (int64_t a, int64_t b)
	Return the greatest common divisor of a and b.
int64_t	av_rescale_rnd (int64_t a, int64_t b, int64_t c, enum AVRounding rnd)
	Rescale a 64-bit integer with specified rounding.
int64_t	av_rescale (int64_t a, int64_t b, int64_t c)
	Rescale a 64-bit integer with rounding to nearest.
int64_t	av_rescale_q_rnd (int64_t a, AVRational bq, AVRational cq, enum AVRounding rnd)
	Rescale a 64-bit integer by 2 rational numbers with specified rounding.
int64_t	av_rescale_q (int64_t a, AVRational bq, AVRational cq)
	Rescale a 64-bit integer by 2 rational numbers.
int	av_compare_ts (int64_t ts_a, AVRational tb_a, int64_t ts_b, AVRational tb_b)
	Compare 2 timestamps each in its own timebases.
int64_t	av_compare_mod (uint64_t a, uint64_t b, uint64_t mod)
	Compare 2 integers modulo mod.
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.
int64_t	av_add_stable (AVRational ts_tb, int64_t ts, AVRational inc_tb, int64_t inc)
	Add a value to a timestamp.

Variables
const uint8_t	av_reverse [256]
	Reverse the order of the bits of an 8-bits unsigned integer.

Detailed Description

miscellaneous math routines and tables

Definition in file mathematics.c.

Variable Documentation

const uint8_t av_reverse[256]

Initial value:

= {
0x00,0x80,0x40,0xC0,0x20,0xA0,0x60,0xE0,0x10,0x90,0x50,0xD0,0x30,0xB0,0x70,0xF0,
0x08,0x88,0x48,0xC8,0x28,0xA8,0x68,0xE8,0x18,0x98,0x58,0xD8,0x38,0xB8,0x78,0xF8,
0x04,0x84,0x44,0xC4,0x24,0xA4,0x64,0xE4,0x14,0x94,0x54,0xD4,0x34,0xB4,0x74,0xF4,
0x0C,0x8C,0x4C,0xCC,0x2C,0xAC,0x6C,0xEC,0x1C,0x9C,0x5C,0xDC,0x3C,0xBC,0x7C,0xFC,
0x02,0x82,0x42,0xC2,0x22,0xA2,0x62,0xE2,0x12,0x92,0x52,0xD2,0x32,0xB2,0x72,0xF2,
0x0A,0x8A,0x4A,0xCA,0x2A,0xAA,0x6A,0xEA,0x1A,0x9A,0x5A,0xDA,0x3A,0xBA,0x7A,0xFA,
0x06,0x86,0x46,0xC6,0x26,0xA6,0x66,0xE6,0x16,0x96,0x56,0xD6,0x36,0xB6,0x76,0xF6,
0x0E,0x8E,0x4E,0xCE,0x2E,0xAE,0x6E,0xEE,0x1E,0x9E,0x5E,0xDE,0x3E,0xBE,0x7E,0xFE,
0x01,0x81,0x41,0xC1,0x21,0xA1,0x61,0xE1,0x11,0x91,0x51,0xD1,0x31,0xB1,0x71,0xF1,
0x09,0x89,0x49,0xC9,0x29,0xA9,0x69,0xE9,0x19,0x99,0x59,0xD9,0x39,0xB9,0x79,0xF9,
0x05,0x85,0x45,0xC5,0x25,0xA5,0x65,0xE5,0x15,0x95,0x55,0xD5,0x35,0xB5,0x75,0xF5,
0x0D,0x8D,0x4D,0xCD,0x2D,0xAD,0x6D,0xED,0x1D,0x9D,0x5D,0xDD,0x3D,0xBD,0x7D,0xFD,
0x03,0x83,0x43,0xC3,0x23,0xA3,0x63,0xE3,0x13,0x93,0x53,0xD3,0x33,0xB3,0x73,0xF3,
0x0B,0x8B,0x4B,0xCB,0x2B,0xAB,0x6B,0xEB,0x1B,0x9B,0x5B,0xDB,0x3B,0xBB,0x7B,0xFB,
0x07,0x87,0x47,0xC7,0x27,0xA7,0x67,0xE7,0x17,0x97,0x57,0xD7,0x37,0xB7,0x77,0xF7,
0x0F,0x8F,0x4F,0xCF,0x2F,0xAF,0x6F,0xEF,0x1F,0x9F,0x5F,0xDF,0x3F,0xBF,0x7F,0xFF,
}

Reverse the order of the bits of an 8-bits unsigned integer.

Definition at line 35 of file mathematics.c.

Referenced by eval_expr().