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ffmpeg/libavcodec/aac/aacdec.h

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/*
* AAC decoder definitions and structures
* Copyright (c) 2005-2006 Oded Shimon ( ods15 ods15 dyndns org )
* Copyright (c) 2006-2007 Maxim Gavrilov ( maxim.gavrilov gmail com )
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* AAC decoder definitions and structures
* @author Oded Shimon ( ods15 ods15 dyndns org )
* @author Maxim Gavrilov ( maxim.gavrilov gmail com )
*/
#ifndef AVCODEC_AAC_AACDEC_H
#define AVCODEC_AAC_AACDEC_H
#include <stdint.h>
#include "libavutil/channel_layout.h"
#include "libavutil/float_dsp.h"
#include "libavutil/fixed_dsp.h"
#include "libavutil/mem_internal.h"
#include "libavutil/tx.h"
#include "libavcodec/aac.h"
#include "libavcodec/mpeg4audio.h"
typedef struct AACDecContext AACDecContext;
/**
* Output configuration status
*/
enum OCStatus {
OC_NONE, ///< Output unconfigured
OC_TRIAL_PCE, ///< Output configuration under trial specified by an inband PCE
OC_TRIAL_FRAME, ///< Output configuration under trial specified by a frame header
OC_GLOBAL_HDR, ///< Output configuration set in a global header but not yet locked
OC_LOCKED, ///< Output configuration locked in place
};
enum AACOutputChannelOrder {
CHANNEL_ORDER_DEFAULT,
CHANNEL_ORDER_CODED,
};
/**
* The point during decoding at which channel coupling is applied.
*/
enum CouplingPoint {
BEFORE_TNS,
BETWEEN_TNS_AND_IMDCT,
AFTER_IMDCT = 3,
};
// Supposed to be equal to AAC_RENAME() in case of USE_FIXED.
#define RENAME_FIXED(name) name ## _fixed
#define INTFLOAT_UNION(name, elems) \
union { \
int RENAME_FIXED(name) elems; \
float name elems; \
}
#define INTFLOAT_ALIGNED_UNION(alignment, name, nb_elems) \
union { \
DECLARE_ALIGNED(alignment, int, RENAME_FIXED(name))[nb_elems]; \
DECLARE_ALIGNED(alignment, float, name)[nb_elems]; \
}
/**
* Long Term Prediction
*/
typedef struct LongTermPrediction {
int8_t present;
int16_t lag;
INTFLOAT_UNION(coef,);
int8_t used[MAX_LTP_LONG_SFB];
} LongTermPrediction;
/**
* Individual Channel Stream
*/
typedef struct IndividualChannelStream {
uint8_t max_sfb; ///< number of scalefactor bands per group
enum WindowSequence window_sequence[2];
uint8_t use_kb_window[2]; ///< If set, use Kaiser-Bessel window, otherwise use a sine window.
int num_window_groups;
uint8_t group_len[8];
LongTermPrediction ltp;
const uint16_t *swb_offset; ///< table of offsets to the lowest spectral coefficient of a scalefactor band, sfb, for a particular window
int num_swb; ///< number of scalefactor window bands
int num_windows;
int tns_max_bands;
int predictor_present;
int predictor_initialized;
int predictor_reset_group;
uint8_t prediction_used[41];
uint8_t window_clipping[8]; ///< set if a certain window is near clipping
} IndividualChannelStream;
/**
* Temporal Noise Shaping
*/
typedef struct TemporalNoiseShaping {
int present;
int n_filt[8];
int length[8][4];
int direction[8][4];
int order[8][4];
INTFLOAT_UNION(coef, [8][4][TNS_MAX_ORDER]);
} TemporalNoiseShaping;
/**
* coupling parameters
*/
typedef struct ChannelCoupling {
enum CouplingPoint coupling_point; ///< The point during decoding at which coupling is applied.
int num_coupled; ///< number of target elements
enum RawDataBlockType type[8]; ///< Type of channel element to be coupled - SCE or CPE.
int id_select[8]; ///< element id
int ch_select[8]; /**< [0] shared list of gains; [1] list of gains for right channel;
* [2] list of gains for left channel; [3] lists of gains for both channels
*/
INTFLOAT_UNION(gain, [16][120]);
} ChannelCoupling;
/**
* Single Channel Element - used for both SCE and LFE elements.
*/
typedef struct SingleChannelElement {
IndividualChannelStream ics;
TemporalNoiseShaping tns;
enum BandType band_type[128]; ///< band types
int band_type_run_end[120]; ///< band type run end points
int sfo[120]; ///< scalefactor offsets
INTFLOAT_UNION(sf, [120]); ///< scalefactors
INTFLOAT_ALIGNED_UNION(32, coeffs, 1024); ///< coefficients for IMDCT, maybe processed
INTFLOAT_ALIGNED_UNION(32, saved, 1536); ///< overlap
INTFLOAT_ALIGNED_UNION(32, ret_buf, 2048); ///< PCM output buffer
INTFLOAT_ALIGNED_UNION(16, ltp_state, 3072); ///< time signal for LTP
union {
struct PredictorStateFixed *RENAME_FIXED(predictor_state);
struct PredictorState *predictor_state;
};
union {
float *output; ///< PCM output
int *RENAME_FIXED(output); ///< PCM output
};
} SingleChannelElement;
/**
* channel element - generic struct for SCE/CPE/CCE/LFE
*/
typedef struct ChannelElement {
int present;
// CPE specific
uint8_t ms_mask[128]; ///< Set if mid/side stereo is used for each scalefactor window band
// shared
SingleChannelElement ch[2];
// CCE specific
ChannelCoupling coup;
} ChannelElement;
typedef struct OutputConfiguration {
MPEG4AudioConfig m4ac;
uint8_t layout_map[MAX_ELEM_ID*4][3];
int layout_map_tags;
AVChannelLayout ch_layout;
enum OCStatus status;
} OutputConfiguration;
/**
* Dynamic Range Control - decoded from the bitstream but not processed further.
*/
typedef struct DynamicRangeControl {
int pce_instance_tag; ///< Indicates with which program the DRC info is associated.
int dyn_rng_sgn[17]; ///< DRC sign information; 0 - positive, 1 - negative
int dyn_rng_ctl[17]; ///< DRC magnitude information
int exclude_mask[MAX_CHANNELS]; ///< Channels to be excluded from DRC processing.
int band_incr; ///< Number of DRC bands greater than 1 having DRC info.
int interpolation_scheme; ///< Indicates the interpolation scheme used in the SBR QMF domain.
int band_top[17]; ///< Indicates the top of the i-th DRC band in units of 4 spectral lines.
int prog_ref_level; /**< A reference level for the long-term program audio level for all
* channels combined.
*/
} DynamicRangeControl;
/**
* Decode-specific primitives
*/
typedef struct AACDecProc {
int (*decode_spectrum_and_dequant)(AACDecContext *ac,
GetBitContext *gb,
const Pulse *pulse,
SingleChannelElement *sce);
int (*decode_cce)(AACDecContext *ac, GetBitContext *gb, ChannelElement *che);
} AACDecProc;
/**
* DSP-specific primitives
*/
typedef struct AACDecDSP {
int (*init)(AACDecContext *ac);
void (*dequant_scalefactors)(SingleChannelElement *sce);
void (*apply_mid_side_stereo)(AACDecContext *ac, ChannelElement *cpe);
void (*apply_intensity_stereo)(AACDecContext *ac, ChannelElement *cpe,
int ms_present);
void (*apply_tns)(void *_coef_param, TemporalNoiseShaping *tns,
IndividualChannelStream *ics, int decode);
void (*apply_ltp)(AACDecContext *ac, SingleChannelElement *sce);
void (*update_ltp)(AACDecContext *ac, SingleChannelElement *sce);
void (*apply_prediction)(AACDecContext *ac, SingleChannelElement *sce);
void (*apply_dependent_coupling)(AACDecContext *ac,
SingleChannelElement *target,
ChannelElement *cce, int index);
void (*apply_independent_coupling)(AACDecContext *ac,
SingleChannelElement *target,
ChannelElement *cce, int index);
void (*imdct_and_windowing)(AACDecContext *ac, SingleChannelElement *sce);
void (*imdct_and_windowing_960)(AACDecContext *ac, SingleChannelElement *sce);
void (*imdct_and_windowing_ld)(AACDecContext *ac, SingleChannelElement *sce);
void (*imdct_and_windowing_eld)(AACDecContext *ac, SingleChannelElement *sce);
void (*clip_output)(AACDecContext *ac, ChannelElement *che, int type, int samples);
} AACDecDSP;
/**
* main AAC decoding context
*/
struct AACDecContext {
const struct AVClass *class;
struct AVCodecContext *avctx;
AACDecDSP dsp;
AACDecProc proc;
struct AVFrame *frame;
int is_saved; ///< Set if elements have stored overlap from previous frame.
DynamicRangeControl che_drc;
/**
* @name Channel element related data
* @{
*/
ChannelElement *che[4][MAX_ELEM_ID];
ChannelElement *tag_che_map[4][MAX_ELEM_ID];
int tags_mapped;
int warned_remapping_once;
/** @} */
/**
* @name temporary aligned temporary buffers
* (We do not want to have these on the stack.)
* @{
*/
INTFLOAT_ALIGNED_UNION(32, buf_mdct, 1024);
INTFLOAT_ALIGNED_UNION(32, temp, 128);
/** @} */
/**
* @name Computed / set up during initialization
* @{
*/
AVTXContext *mdct120;
AVTXContext *mdct128;
AVTXContext *mdct480;
AVTXContext *mdct512;
AVTXContext *mdct960;
AVTXContext *mdct1024;
AVTXContext *mdct_ltp;
av_tx_fn mdct120_fn;
av_tx_fn mdct128_fn;
av_tx_fn mdct480_fn;
av_tx_fn mdct512_fn;
av_tx_fn mdct960_fn;
av_tx_fn mdct1024_fn;
av_tx_fn mdct_ltp_fn;
union {
AVFixedDSPContext *RENAME_FIXED(fdsp);
AVFloatDSPContext *fdsp;
};
int random_state;
/** @} */
/**
* @name Members used for output
* @{
*/
SingleChannelElement *output_element[MAX_CHANNELS]; ///< Points to each SingleChannelElement
/** @} */
/**
* @name Japanese DTV specific extension
* @{
*/
int force_dmono_mode;///< 0->not dmono, 1->use first channel, 2->use second channel
int dmono_mode; ///< 0->not dmono, 1->use first channel, 2->use second channel
/** @} */
enum AACOutputChannelOrder output_channel_order;
OutputConfiguration oc[2];
int warned_num_aac_frames;
int warned_960_sbr;
unsigned warned_71_wide;
int warned_gain_control;
int warned_he_aac_mono;
int is_fixed;
};
#if defined(USE_FIXED) && USE_FIXED
#define fdsp RENAME_FIXED(fdsp)
#endif
extern const AACDecDSP aac_dsp;
extern const AACDecDSP aac_dsp_fixed;
extern const AACDecProc aac_proc;
extern const AACDecProc aac_proc_fixed;
int ff_aac_decode_ics(AACDecContext *ac, SingleChannelElement *sce,
GetBitContext *gb, int common_window, int scale_flag);
#endif /* AVCODEC_AAC_AACDEC_H */
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