1/* 2 * AAC definitions and structures 3 * Copyright (c) 2005-2006 Oded Shimon ( ods15 ods15 dyndns org ) 4 * Copyright (c) 2006-2007 Maxim Gavrilov ( maxim.gavrilov gmail com ) 5 * 6 * This file is part of FFmpeg. 7 * 8 * FFmpeg is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU Lesser General Public 10 * License as published by the Free Software Foundation; either 11 * version 2.1 of the License, or (at your option) any later version. 12 * 13 * FFmpeg is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * Lesser General Public License for more details. 17 * 18 * You should have received a copy of the GNU Lesser General Public 19 * License along with FFmpeg; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 */ 22 23/** 24 * @file 25 * AAC definitions and structures 26 * @author Oded Shimon ( ods15 ods15 dyndns org ) 27 * @author Maxim Gavrilov ( maxim.gavrilov gmail com ) 28 */ 29 30#ifndef AVCODEC_AAC_H 31#define AVCODEC_AAC_H 32 33#include "libavutil/float_dsp.h" 34#include "avcodec.h" 35#include "fft.h" 36#include "mpeg4audio.h" 37#include "sbr.h" 38#include "fmtconvert.h" 39 40#include <stdint.h> 41 42#define MAX_CHANNELS 64 43#define MAX_ELEM_ID 16 44 45#define TNS_MAX_ORDER 20 46#define MAX_LTP_LONG_SFB 40 47 48enum RawDataBlockType { 49 TYPE_SCE, 50 TYPE_CPE, 51 TYPE_CCE, 52 TYPE_LFE, 53 TYPE_DSE, 54 TYPE_PCE, 55 TYPE_FIL, 56 TYPE_END, 57}; 58 59enum ExtensionPayloadID { 60 EXT_FILL, 61 EXT_FILL_DATA, 62 EXT_DATA_ELEMENT, 63 EXT_DYNAMIC_RANGE = 0xb, 64 EXT_SBR_DATA = 0xd, 65 EXT_SBR_DATA_CRC = 0xe, 66}; 67 68enum WindowSequence { 69 ONLY_LONG_SEQUENCE, 70 LONG_START_SEQUENCE, 71 EIGHT_SHORT_SEQUENCE, 72 LONG_STOP_SEQUENCE, 73}; 74 75enum BandType { 76 ZERO_BT = 0, ///< Scalefactors and spectral data are all zero. 77 FIRST_PAIR_BT = 5, ///< This and later band types encode two values (rather than four) with one code word. 78 ESC_BT = 11, ///< Spectral data are coded with an escape sequence. 79 NOISE_BT = 13, ///< Spectral data are scaled white noise not coded in the bitstream. 80 INTENSITY_BT2 = 14, ///< Scalefactor data are intensity stereo positions. 81 INTENSITY_BT = 15, ///< Scalefactor data are intensity stereo positions. 82}; 83 84#define IS_CODEBOOK_UNSIGNED(x) (((x) - 1) & 10) 85 86enum ChannelPosition { 87 AAC_CHANNEL_OFF = 0, 88 AAC_CHANNEL_FRONT = 1, 89 AAC_CHANNEL_SIDE = 2, 90 AAC_CHANNEL_BACK = 3, 91 AAC_CHANNEL_LFE = 4, 92 AAC_CHANNEL_CC = 5, 93}; 94 95/** 96 * The point during decoding at which channel coupling is applied. 97 */ 98enum CouplingPoint { 99 BEFORE_TNS, 100 BETWEEN_TNS_AND_IMDCT, 101 AFTER_IMDCT = 3, 102}; 103 104/** 105 * Output configuration status 106 */ 107enum OCStatus { 108 OC_NONE, ///< Output unconfigured 109 OC_TRIAL_PCE, ///< Output configuration under trial specified by an inband PCE 110 OC_TRIAL_FRAME, ///< Output configuration under trial specified by a frame header 111 OC_GLOBAL_HDR, ///< Output configuration set in a global header but not yet locked 112 OC_LOCKED, ///< Output configuration locked in place 113}; 114 115typedef struct OutputConfiguration { 116 MPEG4AudioConfig m4ac; 117 uint8_t layout_map[MAX_ELEM_ID*4][3]; 118 int layout_map_tags; 119 int channels; 120 uint64_t channel_layout; 121 enum OCStatus status; 122} OutputConfiguration; 123 124/** 125 * Predictor State 126 */ 127typedef struct PredictorState { 128 float cor0; 129 float cor1; 130 float var0; 131 float var1; 132 float r0; 133 float r1; 134} PredictorState; 135 136#define MAX_PREDICTORS 672 137 138#define SCALE_DIV_512 36 ///< scalefactor difference that corresponds to scale difference in 512 times 139#define SCALE_ONE_POS 140 ///< scalefactor index that corresponds to scale=1.0 140#define SCALE_MAX_POS 255 ///< scalefactor index maximum value 141#define SCALE_MAX_DIFF 60 ///< maximum scalefactor difference allowed by standard 142#define SCALE_DIFF_ZERO 60 ///< codebook index corresponding to zero scalefactor indices difference 143 144/** 145 * Long Term Prediction 146 */ 147typedef struct LongTermPrediction { 148 int8_t present; 149 int16_t lag; 150 float coef; 151 int8_t used[MAX_LTP_LONG_SFB]; 152} LongTermPrediction; 153 154/** 155 * Individual Channel Stream 156 */ 157typedef struct IndividualChannelStream { 158 uint8_t max_sfb; ///< number of scalefactor bands per group 159 enum WindowSequence window_sequence[2]; 160 uint8_t use_kb_window[2]; ///< If set, use Kaiser-Bessel window, otherwise use a sine window. 161 int num_window_groups; 162 uint8_t group_len[8]; 163 LongTermPrediction ltp; 164 const uint16_t *swb_offset; ///< table of offsets to the lowest spectral coefficient of a scalefactor band, sfb, for a particular window 165 const uint8_t *swb_sizes; ///< table of scalefactor band sizes for a particular window 166 int num_swb; ///< number of scalefactor window bands 167 int num_windows; 168 int tns_max_bands; 169 int predictor_present; 170 int predictor_initialized; 171 int predictor_reset_group; 172 uint8_t prediction_used[41]; 173} IndividualChannelStream; 174 175/** 176 * Temporal Noise Shaping 177 */ 178typedef struct TemporalNoiseShaping { 179 int present; 180 int n_filt[8]; 181 int length[8][4]; 182 int direction[8][4]; 183 int order[8][4]; 184 float coef[8][4][TNS_MAX_ORDER]; 185} TemporalNoiseShaping; 186 187/** 188 * Dynamic Range Control - decoded from the bitstream but not processed further. 189 */ 190typedef struct DynamicRangeControl { 191 int pce_instance_tag; ///< Indicates with which program the DRC info is associated. 192 int dyn_rng_sgn[17]; ///< DRC sign information; 0 - positive, 1 - negative 193 int dyn_rng_ctl[17]; ///< DRC magnitude information 194 int exclude_mask[MAX_CHANNELS]; ///< Channels to be excluded from DRC processing. 195 int band_incr; ///< Number of DRC bands greater than 1 having DRC info. 196 int interpolation_scheme; ///< Indicates the interpolation scheme used in the SBR QMF domain. 197 int band_top[17]; ///< Indicates the top of the i-th DRC band in units of 4 spectral lines. 198 int prog_ref_level; /**< A reference level for the long-term program audio level for all 199 * channels combined. 200 */ 201} DynamicRangeControl; 202 203typedef struct Pulse { 204 int num_pulse; 205 int start; 206 int pos[4]; 207 int amp[4]; 208} Pulse; 209 210/** 211 * coupling parameters 212 */ 213typedef struct ChannelCoupling { 214 enum CouplingPoint coupling_point; ///< The point during decoding at which coupling is applied. 215 int num_coupled; ///< number of target elements 216 enum RawDataBlockType type[8]; ///< Type of channel element to be coupled - SCE or CPE. 217 int id_select[8]; ///< element id 218 int ch_select[8]; /**< [0] shared list of gains; [1] list of gains for right channel; 219 * [2] list of gains for left channel; [3] lists of gains for both channels 220 */ 221 float gain[16][120]; 222} ChannelCoupling; 223 224/** 225 * Single Channel Element - used for both SCE and LFE elements. 226 */ 227typedef struct SingleChannelElement { 228 IndividualChannelStream ics; 229 TemporalNoiseShaping tns; 230 Pulse pulse; 231 enum BandType band_type[128]; ///< band types 232 int band_type_run_end[120]; ///< band type run end points 233 float sf[120]; ///< scalefactors 234 int sf_idx[128]; ///< scalefactor indices (used by encoder) 235 uint8_t zeroes[128]; ///< band is not coded (used by encoder) 236 DECLARE_ALIGNED(32, float, coeffs)[1024]; ///< coefficients for IMDCT 237 DECLARE_ALIGNED(32, float, saved)[1536]; ///< overlap 238 DECLARE_ALIGNED(32, float, ret_buf)[2048]; ///< PCM output buffer 239 DECLARE_ALIGNED(16, float, ltp_state)[3072]; ///< time signal for LTP 240 PredictorState predictor_state[MAX_PREDICTORS]; 241 float *ret; ///< PCM output 242} SingleChannelElement; 243 244/** 245 * channel element - generic struct for SCE/CPE/CCE/LFE 246 */ 247typedef struct ChannelElement { 248 // CPE specific 249 int common_window; ///< Set if channels share a common 'IndividualChannelStream' in bitstream. 250 int ms_mode; ///< Signals mid/side stereo flags coding mode (used by encoder) 251 uint8_t ms_mask[128]; ///< Set if mid/side stereo is used for each scalefactor window band 252 // shared 253 SingleChannelElement ch[2]; 254 // CCE specific 255 ChannelCoupling coup; 256 SpectralBandReplication sbr; 257} ChannelElement; 258 259/** 260 * main AAC context 261 */ 262struct AACContext { 263 AVClass *class; 264 AVCodecContext *avctx; 265 AVFrame *frame; 266 267 int is_saved; ///< Set if elements have stored overlap from previous frame. 268 DynamicRangeControl che_drc; 269 270 /** 271 * @name Channel element related data 272 * @{ 273 */ 274 ChannelElement *che[4][MAX_ELEM_ID]; 275 ChannelElement *tag_che_map[4][MAX_ELEM_ID]; 276 int tags_mapped; 277 /** @} */ 278 279 /** 280 * @name temporary aligned temporary buffers 281 * (We do not want to have these on the stack.) 282 * @{ 283 */ 284 DECLARE_ALIGNED(32, float, buf_mdct)[1024]; 285 /** @} */ 286 287 /** 288 * @name Computed / set up during initialization 289 * @{ 290 */ 291 FFTContext mdct; 292 FFTContext mdct_small; 293 FFTContext mdct_ld; 294 FFTContext mdct_ltp; 295 FmtConvertContext fmt_conv; 296 AVFloatDSPContext fdsp; 297 int random_state; 298 /** @} */ 299 300 /** 301 * @name Members used for output 302 * @{ 303 */ 304 SingleChannelElement *output_element[MAX_CHANNELS]; ///< Points to each SingleChannelElement 305 /** @} */ 306 307 308 /** 309 * @name Japanese DTV specific extension 310 * @{ 311 */ 312 int force_dmono_mode;///< 0->not dmono, 1->use first channel, 2->use second channel 313 int dmono_mode; ///< 0->not dmono, 1->use first channel, 2->use second channel 314 /** @} */ 315 316 DECLARE_ALIGNED(32, float, temp)[128]; 317 318 OutputConfiguration oc[2]; 319 int warned_num_aac_frames; 320 321 /* aacdec functions pointers */ 322 void (*imdct_and_windowing)(AACContext *ac, SingleChannelElement *sce); 323 void (*apply_ltp)(AACContext *ac, SingleChannelElement *sce); 324 void (*apply_tns)(float coef[1024], TemporalNoiseShaping *tns, 325 IndividualChannelStream *ics, int decode); 326 void (*windowing_and_mdct_ltp)(AACContext *ac, float *out, 327 float *in, IndividualChannelStream *ics); 328 void (*update_ltp)(AACContext *ac, SingleChannelElement *sce); 329 330}; 331 332void ff_aacdec_init_mips(AACContext *c); 333 334#endif /* AVCODEC_AAC_H */ 335