libavcodec/fft.h File Reference

#include <stdint.h>
#include "config.h"
#include "libavutil/mem.h"
#include "avfft.h"

Go to the source code of this file.

Data Structures
struct	FFTContext
Defines
#define	FF_FFT_PERM_DEFAULT   0
#define	FF_FFT_PERM_SWAP_LSBS   1
#define	FF_MDCT_PERM_NONE   0
#define	FF_MDCT_PERM_INTERLEAVE   1
#define	COSTABLE_CONST
#define	COSTABLE(size)   COSTABLE_CONST DECLARE_ALIGNED(16, FFTSample, ff_cos_##size)[size/2]
Functions
	COSTABLE (16)
	COSTABLE (32)
	COSTABLE (64)
	COSTABLE (128)
	COSTABLE (256)
	COSTABLE (512)
	COSTABLE (1024)
	COSTABLE (2048)
	COSTABLE (4096)
	COSTABLE (8192)
	COSTABLE (16384)
	COSTABLE (32768)
	COSTABLE (65536)
void	ff_init_ff_cos_tabs (int index)
	Initialize the cosine table in ff_cos_tabs[index].
int	ff_fft_init (FFTContext *s, int nbits, int inverse)
	Set up a complex FFT.
void	ff_fft_init_altivec (FFTContext *s)
void	ff_fft_init_mmx (FFTContext *s)
void	ff_fft_init_arm (FFTContext *s)
void	ff_dct_init_mmx (DCTContext *s)
void	ff_fft_end (FFTContext *s)
int	ff_mdct_init (FFTContext *s, int nbits, int inverse, double scale)
	init MDCT or IMDCT computation.
void	ff_imdct_calc_c (FFTContext *s, FFTSample *output, const FFTSample *input)
	Compute inverse MDCT of size N = 2^nbits.
void	ff_imdct_half_c (FFTContext *s, FFTSample *output, const FFTSample *input)
	Compute the middle half of the inverse MDCT of size N = 2^nbits, thus excluding the parts that can be derived by symmetry.
void	ff_mdct_calc_c (FFTContext *s, FFTSample *output, const FFTSample *input)
	Compute MDCT of size N = 2^nbits.
void	ff_mdct_end (FFTContext *s)
Variables
COSTABLE_CONST FFTSample *const	ff_cos_tabs [17]

---

Define Documentation

#define COSTABLE

(

size

)

COSTABLE_CONST DECLARE_ALIGNED(16, FFTSample, ff_cos_##size)[size/2]

Definition at line 68 of file fft.h.

#define COSTABLE_CONST

Definition at line 65 of file fft.h.

#define FF_FFT_PERM_DEFAULT   0

Definition at line 55 of file fft.h.

Referenced by ff_fft_init().

#define FF_FFT_PERM_SWAP_LSBS   1

Definition at line 56 of file fft.h.

Referenced by ff_fft_init(), and ff_fft_init_mmx().

#define FF_MDCT_PERM_INTERLEAVE   1

Definition at line 59 of file fft.h.

Referenced by ff_fft_init_arm(), and ff_mdct_init().

#define FF_MDCT_PERM_NONE   0

Definition at line 58 of file fft.h.

Referenced by ff_mdct_init().

---

Function Documentation

COSTABLE

(

65536

)

COSTABLE

(

32768

)

COSTABLE

(

16384

)

COSTABLE

(

8192

)

COSTABLE

(

4096

)

COSTABLE

(

2048

)

COSTABLE

(

1024

)

COSTABLE

(

512

)

COSTABLE

(

256

)

COSTABLE

(

128

)

COSTABLE

(

64

)

COSTABLE

(

32

)

COSTABLE

(

16

)

void ff_dct_init_mmx

(

DCTContext *

s

)

Referenced by ff_dct_init().

void ff_fft_end

(

FFTContext *

s

)

Definition at line 141 of file fft.c.

Referenced by av_fft_end(), ff_mdct_end(), ff_rdft_end(), imc_decode_close(), and main().

int ff_fft_init	(	FFTContext *	s,
		int	nbits,
		int	inverse
	)

Set up a complex FFT.

Parameters:

	nbits	log2 of the length of the input array
	inverse	if 0 perform the forward transform, if 1 perform the inverse

Definition at line 84 of file fft.c.

Referenced by av_fft_init(), ff_mdct_init(), ff_rdft_init(), imc_decode_init(), and main().

void ff_fft_init_altivec

(

FFTContext *

s

)

Definition at line 140 of file fft_altivec.c.

Referenced by ff_fft_init().

void ff_fft_init_arm

(

FFTContext *

s

)

Definition at line 40 of file fft_init_arm.c.

Referenced by ff_fft_init().

void ff_fft_init_mmx

(

FFTContext *

s

)

Definition at line 24 of file fft.c.

Referenced by ff_fft_init().

void ff_imdct_calc_c	(	FFTContext *	s,
		FFTSample *	output,
		const FFTSample *	input
	)

Compute inverse MDCT of size N = 2^nbits.

Parameters:

	output	N samples
	input	N/2 samples

Definition at line 141 of file mdct.c.

Referenced by ff_fft_init().

void ff_imdct_half_c	(	FFTContext *	s,
		FFTSample *	output,
		const FFTSample *	input
	)

Compute the middle half of the inverse MDCT of size N = 2^nbits, thus excluding the parts that can be derived by symmetry.

Parameters:

	output	N/2 samples
	input	N/2 samples

Definition at line 99 of file mdct.c.

Referenced by ff_fft_init(), and ff_imdct_calc_c().

void ff_init_ff_cos_tabs

(

int

index

)

Initialize the cosine table in ff_cos_tabs[index].

Parameters:

index

index in ff_cos_tabs array of the table to initialize

Definition at line 70 of file fft.c.

Referenced by ff_dct_init(), ff_fft_init(), and ff_rdft_init().

void ff_mdct_calc_c	(	FFTContext *	s,
		FFTSample *	out,
		const FFTSample *	input
	)

Compute MDCT of size N = 2^nbits.

Parameters:

	input	N samples
	out	N/2 samples

Definition at line 161 of file mdct.c.

Referenced by ff_fft_init().

void ff_mdct_end

(

FFTContext *

s

)

Definition at line 203 of file mdct.c.

Referenced by aac_decode_close(), aac_encode_end(), ac3_decode_end(), atrac1_decode_end(), atrac3_decode_close(), cook_decode_close(), dca_decode_end(), decode_end(), encode_end(), ff_aac_sbr_ctx_close(), ff_mdct_init(), ff_wma_end(), main(), mdct_end(), twin_decode_close(), vorbis_encode_close(), and vorbis_free().

int ff_mdct_init	(	FFTContext *	s,
		int	nbits,
		int	inverse,
		double	scale
	)

init MDCT or IMDCT computation.

Definition at line 36 of file mdct.c.

Referenced by aac_decode_init(), aac_encode_init(), ac3_decode_init(), atrac1_decode_init(), create_vorbis_context(), dca_decode_init(), decode_init(), encode_init(), ff_aac_sbr_ctx_init(), init_atrac3_transforms(), init_cook_mlt(), init_mdct_win(), main(), mdct_init(), vorbis_parse_id_hdr(), and wma_decode_init().

---

Variable Documentation

COSTABLE_CONST FFTSample* const ff_cos_tabs[17]

Definition at line 50 of file fft.c.

Referenced by ff_dct_init(), ff_init_ff_cos_tabs(), and ff_rdft_init().