wmafixed.c File Reference

Include dependency graph for wmafixed.c:

Defines
#define	STEP(k)
Functions
int64_t	IntTo64 (int x)
int	IntFrom64 (int64_t x)
int32_t	Fixed32From64 (int64_t x)
int64_t	Fixed32To64 (int32_t x)
int64_t	fixmul64byfixed (int64_t x, int32_t y)
int32_t	fixdiv32 (int32_t x, int32_t y)
int64_t	fixdiv64 (int64_t x, int64_t y)
int32_t	fixsqrt32 (int32_t x)
long	fsincos (unsigned long phase, int32_t *cos)
	Implements sin and cos using CORDIC rotation.
Variables
static const long	cordic_circular_gain = 0xb2458939
static const unsigned long	atan_table []

---

Define Documentation

#define STEP

(

k

)

Value:

s = r + (1 << k * 2); r >>= 1; \
    if (s <= v) { v -= s; r |= (1 << k * 2); }

Referenced by fixsqrt32().

---

Function Documentation

int32_t fixdiv32	(	int32_t	x,
		int32_t	y
	)

References PRECISION.

Referenced by fft_init_global(), wma_decode_block(), wma_decode_init(), and wma_lsp_to_curve_init().

int64_t fixdiv64	(	int64_t	x,
		int64_t	y
	)

References PRECISION64.

Referenced by wma_decode_block(), and wma_decode_init().

int32_t Fixed32From64

(

int64_t

x

)

Referenced by wma_decode_block().

int64_t Fixed32To64

(

int32_t

x

)

Referenced by wma_decode_block().

int64_t fixmul64byfixed	(	int64_t	x,
		int32_t	y
	)

int32_t fixsqrt32

(

int32_t

x

)

References long(), and STEP.

Referenced by wma_decode_block().

long fsincos	(	unsigned long	phase,
		int32_t *	cos
	)

Implements sin and cos using CORDIC rotation.

Parameters:

	phase	has range from 0 to 0xffffffff, representing 0 and 2*pi respectively.
	cos	return address for cos

Returns:

sin of phase, value is a signed value from LONG_MIN to LONG_MAX, representing -1 and 1 respectively.

Gives at least 24 bits precision (last 2-8 bits or so are probably off)

References atan_table, cordic_circular_gain, and i.

Referenced by ff_mdct_init(), fft_init_global(), wma_decode_init(), and wma_lsp_to_curve_init().

int IntFrom64

(

int64_t

x

)

int64_t IntTo64

(

int

x

)

---

Variable Documentation

const unsigned long atan_table[] [static]

Referenced by fsincos().

const long cordic_circular_gain = 0xb2458939 [static]

Referenced by fsincos().