celp_math.h File Reference

#include <stdint.h>

Go to the source code of this file.

Functions
int	ff_exp2 (uint16_t power)
	fixed-point implementation of exp2(x) in [0; 1] domain. More...
int	ff_log2_q15 (uint32_t value)
	Calculate log2(x). More...
static int	bidir_sal (int value, int offset)
	Shift value left or right depending on sign of offset parameter. More...

Function Documentation

static int bidir_sal ( int  value, int  offset  )

inlinestatic

Shift value left or right depending on sign of offset parameter.

Parameters

value	value to shift
offset	shift offset

Returns

value << offset, if offset>=0; value >> -offset - otherwise

Definition at line 52 of file celp_math.h.

int ff_exp2

(

uint16_t

power

)

fixed-point implementation of exp2(x) in [0; 1] domain.

Parameters

power

argument to exp2, 0 <= power <= 0x7fff

Returns

value of (1<<20) * exp2(power / (1<<15)) 0x8000c <= result <= 0xfffea

Definition at line 47 of file celp_math.c.

int ff_log2_q15

(

uint32_t

value

)

Calculate log2(x).

Parameters

value

function argument, 0 < value <= 7fff ffff

Returns

value of (1<<15) * log2(value)

Definition at line 70 of file celp_math.c.

Referenced by ff_acelp_update_past_gain().