libavcodec/wma.h File Reference

#include "get_bits.h"
#include "put_bits.h"
#include "dsputil.h"
#include "fft.h"

Go to the source code of this file.

Data Structures
struct	CoefVLCTable
struct	WMACodecContext
Defines
#define	BLOCK_MIN_BITS   7
#define	BLOCK_MAX_BITS   11
#define	BLOCK_MAX_SIZE   (1 << BLOCK_MAX_BITS)
#define	BLOCK_NB_SIZES   (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
#define	HIGH_BAND_MAX_SIZE   16
#define	NB_LSP_COEFS   10
#define	MAX_CODED_SUPERFRAME_SIZE   16384
#define	MAX_CHANNELS   2
#define	NOISE_TAB_SIZE   8192
#define	LSP_POW_BITS   7
#define	VLCBITS   9
#define	VLCMAX   ((22+VLCBITS-1)/VLCBITS)
Typedefs
typedef float	WMACoef
	type for decoded coefficients, int16_t would be enough for wma 1/2
Functions
int av_cold	ff_wma_get_frame_len_bits (int sample_rate, int version, unsigned int decode_flags)
	Get the samples per frame for this stream.
int	ff_wma_init (AVCodecContext *avctx, int flags2)
int	ff_wma_total_gain_to_bits (int total_gain)
int	ff_wma_end (AVCodecContext *avctx)
unsigned int	ff_wma_get_large_val (GetBitContext *gb)
	Decode an uncompressed coefficient.
int	ff_wma_run_level_decode (AVCodecContext *avctx, GetBitContext *gb, VLC *vlc, const float *level_table, const uint16_t *run_table, int version, WMACoef *ptr, int offset, int num_coefs, int block_len, int frame_len_bits, int coef_nb_bits)
	Decode run level compressed coefficients.
Variables
const uint16_t	ff_wma_critical_freqs [25]
const uint16_t	ff_wma_hgain_huffcodes [37]
const uint8_t	ff_wma_hgain_huffbits [37]
const float	ff_wma_lsp_codebook [NB_LSP_COEFS][16]
const uint32_t	ff_aac_scalefactor_code [121]
const uint8_t	ff_aac_scalefactor_bits [121]

---

Define Documentation

#define BLOCK_MAX_BITS   11

Definition at line 32 of file wma.h.

#define BLOCK_MAX_SIZE   (1 << BLOCK_MAX_BITS)

Definition at line 33 of file wma.h.

#define BLOCK_MIN_BITS   7

Definition at line 31 of file wma.h.

Referenced by decode_init(), decode_subframe(), ff_wma_init(), and wmapro_window().

#define BLOCK_NB_SIZES   (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)

Definition at line 35 of file wma.h.

#define HIGH_BAND_MAX_SIZE   16

Definition at line 38 of file wma.h.

Referenced by wma_decode_block().

#define LSP_POW_BITS   7

Definition at line 49 of file wma.h.

Referenced by pow_m1_4(), and wma_lsp_to_curve_init().

#define MAX_CHANNELS   2

Definition at line 45 of file wma.h.

#define MAX_CODED_SUPERFRAME_SIZE   16384

Definition at line 43 of file wma.h.

Referenced by wma_decode_superframe().

#define NB_LSP_COEFS   10

Definition at line 40 of file wma.h.

Referenced by decode_exp_lsp(), and wma_lsp_to_curve().

#define NOISE_TAB_SIZE   8192

Definition at line 47 of file wma.h.

Referenced by ff_wma_init(), and wma_decode_block().

#define VLCBITS   9

Definition at line 52 of file wma.h.

Referenced by decode_coeffs(), decode_init(), decode_scale_factors(), ff_wma_run_level_decode(), and init_coef_vlc().

#define VLCMAX   ((22+VLCBITS-1)/VLCBITS)

Definition at line 53 of file wma.h.

Referenced by ff_wma_run_level_decode().

---

Typedef Documentation

typedef float WMACoef

type for decoded coefficients, int16_t would be enough for wma 1/2

Definition at line 55 of file wma.h.

---

Function Documentation

int ff_wma_end

(

AVCodecContext *

avctx

)

Definition at line 409 of file wma.c.

int av_cold ff_wma_get_frame_len_bits	(	int	sample_rate,
		int	version,
		unsigned int	decode_flags
	)

Get the samples per frame for this stream.

Parameters:

	sample_rate	output sample_rate
	version	wma version
	decode_flags	codec compression features

Returns:

log2 of the number of output samples per frame

Definition at line 76 of file wma.c.

Referenced by decode_init(), and ff_wma_init().

unsigned int ff_wma_get_large_val

(

GetBitContext *

gb

)

Decode an uncompressed coefficient.

Parameters:

s

codec context

Returns:

the decoded coefficient

consumes up to 34 bits

decode length

Definition at line 438 of file wma.c.

Referenced by decode_coeffs(), and ff_wma_run_level_decode().

int ff_wma_init	(	AVCodecContext *	avctx,
		int	flags2
	)

Definition at line 109 of file wma.c.

Referenced by encode_init(), and wma_decode_init().

int ff_wma_run_level_decode	(	AVCodecContext *	avctx,
		GetBitContext *	gb,
		VLC *	vlc,
		const float *	level_table,
		const uint16_t *	run_table,
		int	version,
		WMACoef *	ptr,
		int	offset,
		int	num_coefs,
		int	block_len,
		int	frame_len_bits,
		int	coef_nb_bits
	)

Decode run level compressed coefficients.

Parameters:

	avctx	codec context
	gb	bitstream reader context
	vlc	vlc table for get_vlc2
	level_table	level codes
	run_table	run codes
	version	0 for wma1,2 1 for wmapro
	ptr	output buffer
	offset	offset in the output buffer
	num_coefs	number of input coefficents
	block_len	input buffer length (2^n)
	frame_len_bits	number of bits for escaped run codes
	coef_nb_bits	number of bits for escaped level codes

Returns:

0 on success, -1 otherwise

normal code

EOB

escape

NOTE: this is rather suboptimal. reading block_len_bits would be better

escape decode

NOTE: EOB can be omitted

Definition at line 471 of file wma.c.

Referenced by decode_coeffs(), and wma_decode_block().

int ff_wma_total_gain_to_bits

(

int

total_gain

)

Definition at line 400 of file wma.c.

Referenced by encode_block(), and wma_decode_block().

---

Variable Documentation

const uint8_t ff_aac_scalefactor_bits[121]

Definition at line 70 of file aactab.c.

Referenced by aac_decode_init(), encode_exp_vlc(), encode_scale_factors(), search_for_quantizers_anmr(), search_for_quantizers_twoloop(), and wma_decode_init().

const uint32_t ff_aac_scalefactor_code[121]

Definition at line 51 of file aactab.c.

Referenced by aac_decode_init(), encode_exp_vlc(), encode_scale_factors(), and wma_decode_init().

const uint16_t ff_wma_critical_freqs[25]

Definition at line 33 of file wmadata.h.

const uint8_t ff_wma_hgain_huffbits[37]

Definition at line 67 of file wmadata.h.

Referenced by wma_decode_init().

const uint16_t ff_wma_hgain_huffcodes[37]

Definition at line 59 of file wmadata.h.

Referenced by wma_decode_init().

const float ff_wma_lsp_codebook[NB_LSP_COEFS][16]

Definition at line 75 of file wmadata.h.

Referenced by decode_exp_lsp().