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/*
* AAC encoder
* Copyright (C) 2008 Konstantin Shishkov
*
* 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
*/
#ifndef AVCODEC_AACENC_H
#define AVCODEC_AACENC_H
#include <stdint.h>
#include "libavutil/channel_layout.h"
#include "libavutil/float_dsp.h"
#include "libavutil/mem_internal.h"
#include "libavutil/tx.h"
#include "avcodec.h"
#include "put_bits.h"
#include "aac.h"
#include "aacencdsp.h"
#include "audio_frame_queue.h"
#include "psymodel.h"
#include "lpc.h"
#define CLIP_AVOIDANCE_FACTOR 0.95f
typedef enum AACCoder {
AAC_CODER_ANMR = 0,
AAC_CODER_TWOLOOP,
AAC_CODER_FAST,
AAC_CODER_NB,
}AACCoder;
/**
* Predictor State
*/
typedef struct PredictorState {
float cor0;
float cor1;
float var0;
float var1;
float r0;
float r1;
float k1;
float x_est;
} PredictorState;
typedef struct AACEncOptions {
int coder;
int pns;
int tns;
int ltp;
int pce;
int pred;
int mid_side;
int intensity_stereo;
} AACEncOptions;
/**
* Long Term Prediction
*/
typedef struct LongTermPrediction {
int8_t present;
int16_t lag;
int coef_idx;
float 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.
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
const uint8_t *swb_sizes; ///< table of scalefactor band sizes 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;
int predictor_reset_count[31]; ///< used to count prediction resets
uint8_t prediction_used[41];
uint8_t window_clipping[8]; ///< set if a certain window is near clipping
float clip_avoidance_factor; ///< set if any window is near clipping to the necessary atennuation factor to avoid it
} 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];
int coef_idx[8][4][TNS_MAX_ORDER];
float coef[8][4][TNS_MAX_ORDER];
} TemporalNoiseShaping;
/**
* Single Channel Element - used for both SCE and LFE elements.
*/
typedef struct SingleChannelElement {
IndividualChannelStream ics;
TemporalNoiseShaping tns;
Pulse pulse;
enum BandType band_type[128]; ///< band types
enum BandType band_alt[128]; ///< alternative band type
int sf_idx[128]; ///< scalefactor indices
uint8_t zeroes[128]; ///< band is not coded
uint8_t can_pns[128]; ///< band is allowed to PNS (informative)
float is_ener[128]; ///< Intensity stereo pos
float pns_ener[128]; ///< Noise energy values
DECLARE_ALIGNED(32, float, pcoeffs)[1024]; ///< coefficients for IMDCT, pristine
DECLARE_ALIGNED(32, float, coeffs)[1024]; ///< coefficients for IMDCT, maybe processed
DECLARE_ALIGNED(32, float, ret_buf)[2048]; ///< PCM output buffer
DECLARE_ALIGNED(16, float, ltp_state)[3072]; ///< time signal for LTP
DECLARE_ALIGNED(32, float, lcoeffs)[1024]; ///< MDCT of LTP coefficients
DECLARE_ALIGNED(32, float, prcoeffs)[1024]; ///< Main prediction coefs
PredictorState predictor_state[MAX_PREDICTORS];
} SingleChannelElement;
/**
* channel element - generic struct for SCE/CPE/CCE/LFE
*/
typedef struct ChannelElement {
// CPE specific
int common_window; ///< Set if channels share a common 'IndividualChannelStream' in bitstream.
int ms_mode; ///< Signals mid/side stereo flags coding mode
uint8_t is_mode; ///< Set if any bands have been encoded using intensity stereo
uint8_t ms_mask[128]; ///< Set if mid/side stereo is used for each scalefactor window band
uint8_t is_mask[128]; ///< Set if intensity stereo is used
// shared
SingleChannelElement ch[2];
} ChannelElement;
struct AACEncContext;
typedef struct AACCoefficientsEncoder {
void (*search_for_quantizers)(AVCodecContext *avctx, struct AACEncContext *s,
SingleChannelElement *sce, const float lambda);
void (*encode_window_bands_info)(struct AACEncContext *s, SingleChannelElement *sce,
int win, int group_len, const float lambda);
void (*quantize_and_encode_band)(struct AACEncContext *s, PutBitContext *pb, const float *in, float *out, int size,
int scale_idx, int cb, const float lambda, int rtz);
void (*encode_tns_info)(struct AACEncContext *s, SingleChannelElement *sce);
void (*encode_ltp_info)(struct AACEncContext *s, SingleChannelElement *sce, int common_window);
void (*encode_main_pred)(struct AACEncContext *s, SingleChannelElement *sce);
void (*adjust_common_pred)(struct AACEncContext *s, ChannelElement *cpe);
void (*adjust_common_ltp)(struct AACEncContext *s, ChannelElement *cpe);
void (*apply_main_pred)(struct AACEncContext *s, SingleChannelElement *sce);
void (*apply_tns_filt)(struct AACEncContext *s, SingleChannelElement *sce);
void (*update_ltp)(struct AACEncContext *s, SingleChannelElement *sce);
void (*ltp_insert_new_frame)(struct AACEncContext *s);
void (*set_special_band_scalefactors)(struct AACEncContext *s, SingleChannelElement *sce);
void (*search_for_pns)(struct AACEncContext *s, AVCodecContext *avctx, SingleChannelElement *sce);
void (*mark_pns)(struct AACEncContext *s, AVCodecContext *avctx, SingleChannelElement *sce);
void (*search_for_tns)(struct AACEncContext *s, SingleChannelElement *sce);
void (*search_for_ltp)(struct AACEncContext *s, SingleChannelElement *sce, int common_window);
void (*search_for_ms)(struct AACEncContext *s, ChannelElement *cpe);
void (*search_for_is)(struct AACEncContext *s, AVCodecContext *avctx, ChannelElement *cpe);
void (*search_for_pred)(struct AACEncContext *s, SingleChannelElement *sce);
} AACCoefficientsEncoder;
extern const AACCoefficientsEncoder ff_aac_coders[];
typedef struct AACQuantizeBandCostCacheEntry {
float rd;
float energy;
int bits;
char cb;
char rtz;
uint16_t generation;
} AACQuantizeBandCostCacheEntry;
typedef struct AACPCEInfo {
AVChannelLayout layout;
int num_ele[4]; ///< front, side, back, lfe
int pairing[3][8]; ///< front, side, back
int index[4][8]; ///< front, side, back, lfe
uint8_t config_map[16]; ///< configs the encoder's channel specific settings
uint8_t reorder_map[16]; ///< maps channels from lavc to aac order
} AACPCEInfo;
/**
* AAC encoder context
*/
typedef struct AACEncContext {
AVClass *av_class;
AACEncOptions options; ///< encoding options
PutBitContext pb;
AVTXContext *mdct1024; ///< long (1024 samples) frame transform context
av_tx_fn mdct1024_fn;
AVTXContext *mdct128; ///< short (128 samples) frame transform context
av_tx_fn mdct128_fn;
AVFloatDSPContext *fdsp;
AACPCEInfo pce; ///< PCE data, if needed
float *planar_samples[16]; ///< saved preprocessed input
int profile; ///< copied from avctx
int needs_pce; ///< flag for non-standard layout
LPCContext lpc; ///< used by TNS
int samplerate_index; ///< MPEG-4 samplerate index
int channels; ///< channel count
const uint8_t *reorder_map; ///< lavc to aac reorder map
const uint8_t *chan_map; ///< channel configuration map
ChannelElement *cpe; ///< channel elements
FFPsyContext psy;
struct FFPsyPreprocessContext* psypp;
const AACCoefficientsEncoder *coder;
int cur_channel; ///< current channel for coder context
int random_state;
float lambda;
int last_frame_pb_count; ///< number of bits for the previous frame
float lambda_sum; ///< sum(lambda), for Qvg reporting
int lambda_count; ///< count(lambda), for Qvg reporting
enum RawDataBlockType cur_type; ///< channel group type cur_channel belongs to
AudioFrameQueue afq;
DECLARE_ALIGNED(32, int, qcoefs)[96]; ///< quantized coefficients
DECLARE_ALIGNED(32, float, scoefs)[1024]; ///< scaled coefficients
uint16_t quantize_band_cost_cache_generation;
AACQuantizeBandCostCacheEntry quantize_band_cost_cache[256][128]; ///< memoization area for quantize_band_cost
AACEncDSPContext aacdsp;
struct {
float *samples;
} buffer;
} AACEncContext;
void ff_quantize_band_cost_cache_init(struct AACEncContext *s);
#endif /* AVCODEC_AACENC_H */
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