atrac3plus.h File Reference

Global structures, constants and data for ATRAC3+ decoder. More...

#include <stdint.h>
#include "libavutil/float_dsp.h"
#include "libavutil/mem_internal.h"
#include "libavutil/tx.h"
#include "atrac.h"
#include "avcodec.h"
#include "get_bits.h"

Go to the source code of this file.

Data Structures
struct	Atrac3pIPQFChannelCtx
	Per-channel IPQF history. More...
struct	Atrac3pWaveEnvelope
	Amplitude envelope of a group of sine waves. More...
struct	Atrac3pWavesData
	Parameters of a group of sine waves. More...
struct	Atrac3pWaveParam
	Parameters of a single sine wave. More...
struct	Atrac3pChanParams
	Sound channel parameters. More...
struct	Atrac3pWaveSynthParams
struct	Atrac3pChanUnitCtx
	Channel unit parameters. More...

Macros
#define	ATRAC3P_SUBBANDS   16
	Global unit sizes.
#define	ATRAC3P_SUBBAND_SAMPLES   128
	number of samples per subband
#define	ATRAC3P_FRAME_SAMPLES   (ATRAC3P_SUBBAND_SAMPLES * ATRAC3P_SUBBANDS)
#define	ATRAC3P_PQF_FIR_LEN   12
	length of the prototype FIR of the PQF
#define	ATRAC3P_POWER_COMP_OFF   15
	Global constants.

Enumerations
enum	Atrac3pChannelUnitTypes { CH_UNIT_MONO = 0 , CH_UNIT_STEREO = 1 , CH_UNIT_EXTENSION = 2 , CH_UNIT_TERMINATOR = 3 }
	ATRAC3+ channel unit types. More...

Functions
void	ff_atrac3p_init_vlcs (void)
	Initialize VLC tables for bitstream parsing.
int	ff_atrac3p_decode_channel_unit (GetBitContext *gb, Atrac3pChanUnitCtx *ctx, int num_channels, AVCodecContext *avctx)
	Decode bitstream data of a channel unit.
void	ff_atrac3p_init_dsp_static (void)
	Initialize sine waves synthesizer and ff_sine_* tables.
void	ff_atrac3p_generate_tones (Atrac3pChanUnitCtx *ch_unit, AVFloatDSPContext *fdsp, int ch_num, int sb, float *out)
	Synthesize sine waves for a particular subband.
void	ff_atrac3p_power_compensation (Atrac3pChanUnitCtx *ctx, AVFloatDSPContext *fdsp, int ch_index, float *sp, int rng_index, int sb_num)
	Perform power compensation aka noise dithering.
void	ff_atrac3p_imdct (AVFloatDSPContext *fdsp, AVTXContext *mdct_ctx, av_tx_fn mdct_fn, float *pIn, float *pOut, int wind_id, int sb)
	Regular IMDCT and windowing without overlapping, with spectrum reversal in the odd subbands.
void	ff_atrac3p_ipqf (AVTXContext *dct_ctx, av_tx_fn dct_fn, Atrac3pIPQFChannelCtx *hist, const float *in, float *out)
	Subband synthesis filter based on the polyphase quadrature (pseudo-QMF) filter bank.

Variables
const uint16_t	ff_atrac3p_qu_to_spec_pos [33]
	Map quant unit number to its position in the spectrum.
const float	ff_atrac3p_sf_tab [64]
const float	ff_atrac3p_mant_tab [8]

Detailed Description

Global structures, constants and data for ATRAC3+ decoder.

Definition in file atrac3plus.h.

Macro Definition Documentation

ATRAC3P_SUBBANDS

#define ATRAC3P_SUBBANDS   16

Global unit sizes.

number of PQF subbands

Definition at line 42 of file atrac3plus.h.

Referenced by decode_gainc_data(), decode_residual_spectrum(), decode_tones_info(), ff_atrac3p_ipqf(), and reconstruct_frame().

ATRAC3P_SUBBAND_SAMPLES

#define ATRAC3P_SUBBAND_SAMPLES   128

number of samples per subband

Definition at line 43 of file atrac3plus.h.

Referenced by decode_residual_spectrum(), ff_atrac3p_imdct(), ff_atrac3p_ipqf(), ff_atrac3p_power_compensation(), and reconstruct_frame().

ATRAC3P_FRAME_SAMPLES

#define ATRAC3P_FRAME_SAMPLES   (ATRAC3P_SUBBAND_SAMPLES * ATRAC3P_SUBBANDS)

Definition at line 44 of file atrac3plus.h.

Referenced by atrac3p_decode_frame(), decode_residual_spectrum(), and ff_atrac3p_ipqf().

ATRAC3P_PQF_FIR_LEN

#define ATRAC3P_PQF_FIR_LEN   12

length of the prototype FIR of the PQF

Definition at line 46 of file atrac3plus.h.

Referenced by ff_atrac3p_ipqf().

ATRAC3P_POWER_COMP_OFF

#define ATRAC3P_POWER_COMP_OFF   15

Global constants.

disable power compensation

Definition at line 49 of file atrac3plus.h.

Referenced by decode_spectrum(), and ff_atrac3p_power_compensation().

Enumeration Type Documentation

Atrac3pChannelUnitTypes

enum Atrac3pChannelUnitTypes

ATRAC3+ channel unit types.

Enumerator
CH_UNIT_MONO	unit containing one coded channel
CH_UNIT_STEREO	unit containing two jointly-coded channels
CH_UNIT_EXTENSION	unit containing extension information
CH_UNIT_TERMINATOR	unit sequence terminator

Definition at line 52 of file atrac3plus.h.

Function Documentation

ff_atrac3p_init_vlcs()

void ff_atrac3p_init_vlcs

(

void

)

Initialize VLC tables for bitstream parsing.

Definition at line 76 of file atrac3plus.c.

Referenced by atrac3p_init_static().

ff_atrac3p_decode_channel_unit()

int ff_atrac3p_decode_channel_unit	(	GetBitContext *	gb,
		Atrac3pChanUnitCtx *	ctx,
		int	num_channels,
		AVCodecContext *	avctx )

Decode bitstream data of a channel unit.

Parameters

[in]	gb	the GetBit context
[in,out]	ctx	ptr to the channel unit context
[in]	num_channels	number of channels to process
[in]	avctx	ptr to the AVCodecContext

Returns

result code: 0 = OK, otherwise - error code

Definition at line 1662 of file atrac3plus.c.

Referenced by atrac3p_decode_frame().

ff_atrac3p_init_dsp_static()

void ff_atrac3p_init_dsp_static

(

void

)

Initialize sine waves synthesizer and ff_sine_* tables.

Definition at line 88 of file atrac3plusdsp.c.

Referenced by atrac3p_init_static().

ff_atrac3p_generate_tones()

void ff_atrac3p_generate_tones	(	Atrac3pChanUnitCtx *	ch_unit,
		AVFloatDSPContext *	fdsp,
		int	ch_num,
		int	sb,
		float *	out )

Synthesize sine waves for a particular subband.

Parameters

[in]	ch_unit	pointer to the channel unit context
[in]	fdsp	pointer to float DSP context
[in]	ch_num	which channel to process
[in]	sb	which subband to process
[out]	out	receives processed data

Definition at line 178 of file atrac3plusdsp.c.

Referenced by reconstruct_frame().

ff_atrac3p_power_compensation()

void ff_atrac3p_power_compensation	(	Atrac3pChanUnitCtx *	ctx,
		AVFloatDSPContext *	fdsp,
		int	ch_index,
		float *	sp,
		int	rng_index,
		int	sb_num )

Perform power compensation aka noise dithering.

Parameters

[in]	ctx	ptr to the channel context
[in]	fdsp	pointer to float DSP context
[in]	ch_index	which channel to process
[in,out]	sp	ptr to channel spectrum to process
[in]	rng_index	indicates which RNG table to use
[in]	sb_num	which subband to process

Definition at line 412 of file atrac3plusdsp.c.

Referenced by decode_residual_spectrum().

ff_atrac3p_imdct()

void ff_atrac3p_imdct	(	AVFloatDSPContext *	fdsp,
		AVTXContext *	mdct_ctx,
		av_tx_fn	mdct_fn,
		float *	pIn,
		float *	pOut,
		int	wind_id,
		int	sb )

Regular IMDCT and windowing without overlapping, with spectrum reversal in the odd subbands.

Parameters

[in]	fdsp	pointer to float DSP context
[in]	mdct_ctx	pointer to MDCT transform context
[in]	pIn	float input
[out]	pOut	float output
[in]	wind_id	which MDCT window to apply
[in]	sb	subband number

Definition at line 458 of file atrac3plusdsp.c.

Referenced by reconstruct_frame().

ff_atrac3p_ipqf()

void ff_atrac3p_ipqf	(	AVTXContext *	dct_ctx,
		av_tx_fn	dct_fn,
		Atrac3pIPQFChannelCtx *	hist,
		const float *	in,
		float *	out )

Subband synthesis filter based on the polyphase quadrature (pseudo-QMF) filter bank.

Parameters

[in]	dct_ctx	ptr to the pre-initialized IDCT context
[in,out]	hist	ptr to the filter history
[in]	in	input data to process
[out]	out	receives processed data

Definition at line 600 of file atrac3plusdsp.c.

Referenced by reconstruct_frame().

Variable Documentation

ff_atrac3p_qu_to_spec_pos

const uint16_t ff_atrac3p_qu_to_spec_pos[33]

extern

Map quant unit number to its position in the spectrum.

To get the number of spectral lines in each quant unit do the following: num_specs = qu_to_spec_pos[i+1] - qu_to_spec_pos[i]

Definition at line 42 of file atrac3plusdsp.c.

Referenced by decode_residual_spectrum(), decode_spectrum(), and ff_atrac3p_power_compensation().

ff_atrac3p_sf_tab

const float ff_atrac3p_sf_tab[64]

extern

Definition at line 52 of file atrac3plusdsp.c.

Referenced by decode_residual_spectrum(), and ff_atrac3p_power_compensation().

ff_atrac3p_mant_tab

const float ff_atrac3p_mant_tab[8]

extern

Definition at line 67 of file atrac3plusdsp.c.

Referenced by decode_residual_spectrum(), and ff_atrac3p_power_compensation().