FFmpeg
aac.h
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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 
34 #include "aac_defines.h"
35 #include "libavutil/float_dsp.h"
36 #include "libavutil/fixed_dsp.h"
37 #include "libavutil/mem_internal.h"
38 #include "avcodec.h"
39 #if !USE_FIXED
40 #include "mdct15.h"
41 #endif
42 #include "fft.h"
43 #include "mpeg4audio.h"
44 #include "sbr.h"
45 
46 #include <stdint.h>
47 
48 #define MAX_CHANNELS 64
49 #define MAX_ELEM_ID 16
50 
51 #define TNS_MAX_ORDER 20
52 #define MAX_LTP_LONG_SFB 40
53 
54 #define CLIP_AVOIDANCE_FACTOR 0.95f
55 
65 };
66 
72  EXT_SBR_DATA = 0xd,
74 };
75 
81 };
82 
83 enum BandType {
84  ZERO_BT = 0, ///< Scalefactors and spectral data are all zero.
85  FIRST_PAIR_BT = 5, ///< This and later band types encode two values (rather than four) with one code word.
86  ESC_BT = 11, ///< Spectral data are coded with an escape sequence.
87  RESERVED_BT = 12, ///< Band types following are encoded differently from others.
88  NOISE_BT = 13, ///< Spectral data are scaled white noise not coded in the bitstream.
89  INTENSITY_BT2 = 14, ///< Scalefactor data are intensity stereo positions (out of phase).
90  INTENSITY_BT = 15, ///< Scalefactor data are intensity stereo positions (in phase).
91 };
92 
93 #define IS_CODEBOOK_UNSIGNED(x) (((x) - 1) & 10)
94 
102 };
103 
104 /**
105  * The point during decoding at which channel coupling is applied.
106  */
111 };
112 
113 /**
114  * Output configuration status
115  */
116 enum OCStatus {
117  OC_NONE, ///< Output unconfigured
118  OC_TRIAL_PCE, ///< Output configuration under trial specified by an inband PCE
119  OC_TRIAL_FRAME, ///< Output configuration under trial specified by a frame header
120  OC_GLOBAL_HDR, ///< Output configuration set in a global header but not yet locked
121  OC_LOCKED, ///< Output configuration locked in place
122 };
123 
124 typedef struct OutputConfiguration {
126  uint8_t layout_map[MAX_ELEM_ID*4][3];
128  int channels;
129  uint64_t channel_layout;
132 
133 /**
134  * Predictor State
135  */
136 typedef struct PredictorState {
146 
147 #define MAX_PREDICTORS 672
148 
149 #define SCALE_DIV_512 36 ///< scalefactor difference that corresponds to scale difference in 512 times
150 #define SCALE_ONE_POS 140 ///< scalefactor index that corresponds to scale=1.0
151 #define SCALE_MAX_POS 255 ///< scalefactor index maximum value
152 #define SCALE_MAX_DIFF 60 ///< maximum scalefactor difference allowed by standard
153 #define SCALE_DIFF_ZERO 60 ///< codebook index corresponding to zero scalefactor indices difference
154 
155 #define POW_SF2_ZERO 200 ///< ff_aac_pow2sf_tab index corresponding to pow(2, 0);
156 
157 #define NOISE_PRE 256 ///< preamble for NOISE_BT, put in bitstream with the first noise band
158 #define NOISE_PRE_BITS 9 ///< length of preamble
159 #define NOISE_OFFSET 90 ///< subtracted from global gain, used as offset for the preamble
160 
161 /**
162  * Long Term Prediction
163  */
164 typedef struct LongTermPrediction {
165  int8_t present;
166  int16_t lag;
167  int coef_idx;
171 
172 /**
173  * Individual Channel Stream
174  */
175 typedef struct IndividualChannelStream {
176  uint8_t max_sfb; ///< number of scalefactor bands per group
178  uint8_t use_kb_window[2]; ///< If set, use Kaiser-Bessel window, otherwise use a sine window.
180  uint8_t group_len[8];
182  const uint16_t *swb_offset; ///< table of offsets to the lowest spectral coefficient of a scalefactor band, sfb, for a particular window
183  const uint8_t *swb_sizes; ///< table of scalefactor band sizes for a particular window
184  int num_swb; ///< number of scalefactor window bands
190  int predictor_reset_count[31]; ///< used by encoder to count prediction resets
191  uint8_t prediction_used[41];
192  uint8_t window_clipping[8]; ///< set if a certain window is near clipping
193  float clip_avoidance_factor; ///< set if any window is near clipping to the necessary atennuation factor to avoid it
195 
196 /**
197  * Temporal Noise Shaping
198  */
199 typedef struct TemporalNoiseShaping {
200  int present;
201  int n_filt[8];
202  int length[8][4];
203  int direction[8][4];
204  int order[8][4];
208 
209 /**
210  * Dynamic Range Control - decoded from the bitstream but not processed further.
211  */
212 typedef struct DynamicRangeControl {
213  int pce_instance_tag; ///< Indicates with which program the DRC info is associated.
214  int dyn_rng_sgn[17]; ///< DRC sign information; 0 - positive, 1 - negative
215  int dyn_rng_ctl[17]; ///< DRC magnitude information
216  int exclude_mask[MAX_CHANNELS]; ///< Channels to be excluded from DRC processing.
217  int band_incr; ///< Number of DRC bands greater than 1 having DRC info.
218  int interpolation_scheme; ///< Indicates the interpolation scheme used in the SBR QMF domain.
219  int band_top[17]; ///< Indicates the top of the i-th DRC band in units of 4 spectral lines.
220  int prog_ref_level; /**< A reference level for the long-term program audio level for all
221  * channels combined.
222  */
224 
225 typedef struct Pulse {
227  int start;
228  int pos[4];
229  int amp[4];
230 } Pulse;
231 
232 /**
233  * coupling parameters
234  */
235 typedef struct ChannelCoupling {
236  enum CouplingPoint coupling_point; ///< The point during decoding at which coupling is applied.
237  int num_coupled; ///< number of target elements
238  enum RawDataBlockType type[8]; ///< Type of channel element to be coupled - SCE or CPE.
239  int id_select[8]; ///< element id
240  int ch_select[8]; /**< [0] shared list of gains; [1] list of gains for right channel;
241  * [2] list of gains for left channel; [3] lists of gains for both channels
242  */
243  INTFLOAT gain[16][120];
245 
246 /**
247  * Single Channel Element - used for both SCE and LFE elements.
248  */
249 typedef struct SingleChannelElement {
253  enum BandType band_type[128]; ///< band types
254  enum BandType band_alt[128]; ///< alternative band type (used by encoder)
255  int band_type_run_end[120]; ///< band type run end points
256  INTFLOAT sf[120]; ///< scalefactors
257  int sf_idx[128]; ///< scalefactor indices (used by encoder)
258  uint8_t zeroes[128]; ///< band is not coded (used by encoder)
259  uint8_t can_pns[128]; ///< band is allowed to PNS (informative)
260  float is_ener[128]; ///< Intensity stereo pos (used by encoder)
261  float pns_ener[128]; ///< Noise energy values (used by encoder)
262  DECLARE_ALIGNED(32, INTFLOAT, pcoeffs)[1024]; ///< coefficients for IMDCT, pristine
263  DECLARE_ALIGNED(32, INTFLOAT, coeffs)[1024]; ///< coefficients for IMDCT, maybe processed
264  DECLARE_ALIGNED(32, INTFLOAT, saved)[1536]; ///< overlap
265  DECLARE_ALIGNED(32, INTFLOAT, ret_buf)[2048]; ///< PCM output buffer
266  DECLARE_ALIGNED(16, INTFLOAT, ltp_state)[3072]; ///< time signal for LTP
267  DECLARE_ALIGNED(32, AAC_FLOAT, lcoeffs)[1024]; ///< MDCT of LTP coefficients (used by encoder)
268  DECLARE_ALIGNED(32, AAC_FLOAT, prcoeffs)[1024]; ///< Main prediction coefs (used by encoder)
270  INTFLOAT *ret; ///< PCM output
272 
273 /**
274  * channel element - generic struct for SCE/CPE/CCE/LFE
275  */
276 typedef struct ChannelElement {
277  int present;
278  // CPE specific
279  int common_window; ///< Set if channels share a common 'IndividualChannelStream' in bitstream.
280  int ms_mode; ///< Signals mid/side stereo flags coding mode (used by encoder)
281  uint8_t is_mode; ///< Set if any bands have been encoded using intensity stereo (used by encoder)
282  uint8_t ms_mask[128]; ///< Set if mid/side stereo is used for each scalefactor window band
283  uint8_t is_mask[128]; ///< Set if intensity stereo is used (used by encoder)
284  // shared
286  // CCE specific
290 
291 /**
292  * main AAC context
293  */
294 struct AACContext {
295  AVClass *class;
298 
299  int is_saved; ///< Set if elements have stored overlap from previous frame.
301 
302  /**
303  * @name Channel element related data
304  * @{
305  */
310  /** @} */
311 
312  /**
313  * @name temporary aligned temporary buffers
314  * (We do not want to have these on the stack.)
315  * @{
316  */
318  /** @} */
319 
320  /**
321  * @name Computed / set up during initialization
322  * @{
323  */
328 #if USE_FIXED
330 #else
335 #endif /* USE_FIXED */
337  /** @} */
338 
339  /**
340  * @name Members used for output
341  * @{
342  */
343  SingleChannelElement *output_element[MAX_CHANNELS]; ///< Points to each SingleChannelElement
344  /** @} */
345 
346 
347  /**
348  * @name Japanese DTV specific extension
349  * @{
350  */
351  int force_dmono_mode;///< 0->not dmono, 1->use first channel, 2->use second channel
352  int dmono_mode; ///< 0->not dmono, 1->use first channel, 2->use second channel
353  /** @} */
354 
356 
360  unsigned warned_71_wide;
362 
363  /* aacdec functions pointers */
366  void (*apply_tns)(INTFLOAT coef[1024], TemporalNoiseShaping *tns,
367  IndividualChannelStream *ics, int decode);
371  void (*vector_pow43)(int *coefs, int len);
372  void (*subband_scale)(int *dst, int *src, int scale, int offset, int len, void *log_context);
373 
374 };
375 
377 
378 #endif /* AVCODEC_AAC_H */
ChannelCoupling::type
enum RawDataBlockType type[8]
Type of channel element to be coupled - SCE or CPE.
Definition: aac.h:238
MAX_ELEM_ID
#define MAX_ELEM_ID
Definition: aac.h:49
AAC_CHANNEL_BACK
@ AAC_CHANNEL_BACK
Definition: aac.h:99
CouplingPoint
CouplingPoint
The point during decoding at which channel coupling is applied.
Definition: aac.h:107
SingleChannelElement::band_alt
enum BandType band_alt[128]
alternative band type (used by encoder)
Definition: aac.h:254
SingleChannelElement::can_pns
uint8_t can_pns[128]
band is allowed to PNS (informative)
Definition: aac.h:259
TemporalNoiseShaping::order
int order[8][4]
Definition: aac.h:204
SingleChannelElement::pulse
Pulse pulse
Definition: aac.h:252
mem_internal.h
TYPE_FIL
@ TYPE_FIL
Definition: aac.h:63
out
FILE * out
Definition: movenc.c:54
EXT_FILL
@ EXT_FILL
Definition: aac.h:68
TemporalNoiseShaping::direction
int direction[8][4]
Definition: aac.h:203
Pulse::num_pulse
int num_pulse
Definition: aac.h:226
SingleChannelElement::zeroes
uint8_t zeroes[128]
band is not coded (used by encoder)
Definition: aac.h:258
AACContext::subband_scale
void(* subband_scale)(int *dst, int *src, int scale, int offset, int len, void *log_context)
Definition: aac.h:372
PredictorState::var1
AAC_FLOAT var1
Definition: aac.h:140
TemporalNoiseShaping::coef_idx
int coef_idx[8][4][TNS_MAX_ORDER]
Definition: aac.h:205
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
PredictorState::var0
AAC_FLOAT var0
Definition: aac.h:139
TYPE_PCE
@ TYPE_PCE
Definition: aac.h:62
AACContext::tag_che_map
ChannelElement * tag_che_map[4][MAX_ELEM_ID]
Definition: aac.h:307
MAX_PREDICTORS
#define MAX_PREDICTORS
Definition: aac.h:147
mdct15.h
TemporalNoiseShaping::present
int present
Definition: aac.h:200
AVFixedDSPContext
Definition: fixed_dsp.h:56
LongTermPrediction::used
int8_t used[MAX_LTP_LONG_SFB]
Definition: aac.h:169
AACContext::random_state
int random_state
Definition: aac.h:336
SingleChannelElement::pcoeffs
INTFLOAT pcoeffs[1024]
coefficients for IMDCT, pristine
Definition: aac.h:262
SingleChannelElement::ret
INTFLOAT * ret
PCM output.
Definition: aac.h:270
EXT_DYNAMIC_RANGE
@ EXT_DYNAMIC_RANGE
Definition: aac.h:71
ChannelElement::present
int present
Definition: aac.h:277
sbr.h
MPEG4AudioConfig
Definition: mpeg4audio.h:33
DynamicRangeControl
Dynamic Range Control - decoded from the bitstream but not processed further.
Definition: aac.h:212
IndividualChannelStream::num_swb
int num_swb
number of scalefactor window bands
Definition: aac.h:184
AACContext::temp
INTFLOAT temp[128]
Definition: aac.h:355
ChannelCoupling::coupling_point
enum CouplingPoint coupling_point
The point during decoding at which coupling is applied.
Definition: aac.h:236
OC_LOCKED
@ OC_LOCKED
Output configuration locked in place.
Definition: aac.h:121
mpeg4audio.h
AACContext::apply_ltp
void(* apply_ltp)(AACContext *ac, SingleChannelElement *sce)
Definition: aac.h:365
SingleChannelElement::saved
INTFLOAT saved[1536]
overlap
Definition: aac.h:264
LongTermPrediction::coef
INTFLOAT coef
Definition: aac.h:168
SingleChannelElement::ret_buf
INTFLOAT ret_buf[2048]
PCM output buffer.
Definition: aac.h:265
ChannelElement::coup
ChannelCoupling coup
Definition: aac.h:287
ChannelCoupling::id_select
int id_select[8]
element id
Definition: aac.h:239
BEFORE_TNS
@ BEFORE_TNS
Definition: aac.h:108
TYPE_CPE
@ TYPE_CPE
Definition: aac.h:58
ChannelElement::ms_mode
int ms_mode
Signals mid/side stereo flags coding mode (used by encoder)
Definition: aac.h:280
Pulse::amp
int amp[4]
Definition: aac.h:229
Pulse::pos
int pos[4]
Definition: aac.h:228
OutputConfiguration::status
enum OCStatus status
Definition: aac.h:130
TemporalNoiseShaping::length
int length[8][4]
Definition: aac.h:202
Pulse::start
int start
Definition: aac.h:227
scale
static av_always_inline float scale(float x, float s)
Definition: vf_v360.c:1376
PredictorState::r0
AAC_FLOAT r0
Definition: aac.h:141
IndividualChannelStream::prediction_used
uint8_t prediction_used[41]
Definition: aac.h:191
MAX_LTP_LONG_SFB
#define MAX_LTP_LONG_SFB
Definition: aac.h:52
SingleChannelElement::ics
IndividualChannelStream ics
Definition: aac.h:250
AACContext::mdct
FFTContext mdct
Definition: aac.h:324
IndividualChannelStream::predictor_reset_count
int predictor_reset_count[31]
used by encoder to count prediction resets
Definition: aac.h:190
AACContext::warned_960_sbr
int warned_960_sbr
Definition: aac.h:359
AFTER_IMDCT
@ AFTER_IMDCT
Definition: aac.h:110
AACContext::is_saved
int is_saved
Set if elements have stored overlap from previous frame.
Definition: aac.h:299
ZERO_BT
@ ZERO_BT
Scalefactors and spectral data are all zero.
Definition: aac.h:84
DynamicRangeControl::exclude_mask
int exclude_mask[MAX_CHANNELS]
Channels to be excluded from DRC processing.
Definition: aac.h:216
IndividualChannelStream::clip_avoidance_factor
float clip_avoidance_factor
set if any window is near clipping to the necessary atennuation factor to avoid it
Definition: aac.h:193
AACContext::vector_pow43
void(* vector_pow43)(int *coefs, int len)
Definition: aac.h:371
AACContext::mdct_ld
FFTContext mdct_ld
Definition: aac.h:326
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
NOISE_BT
@ NOISE_BT
Spectral data are scaled white noise not coded in the bitstream.
Definition: aac.h:88
OC_TRIAL_FRAME
@ OC_TRIAL_FRAME
Output configuration under trial specified by a frame header.
Definition: aac.h:119
SingleChannelElement::coeffs
INTFLOAT coeffs[1024]
coefficients for IMDCT, maybe processed
Definition: aac.h:263
ChannelCoupling::num_coupled
int num_coupled
number of target elements
Definition: aac.h:237
IndividualChannelStream::swb_sizes
const uint8_t * swb_sizes
table of scalefactor band sizes for a particular window
Definition: aac.h:183
EIGHT_SHORT_SEQUENCE
@ EIGHT_SHORT_SEQUENCE
Definition: aac.h:79
OC_NONE
@ OC_NONE
Output unconfigured.
Definition: aac.h:117
INTENSITY_BT2
@ INTENSITY_BT2
Scalefactor data are intensity stereo positions (out of phase).
Definition: aac.h:89
TYPE_DSE
@ TYPE_DSE
Definition: aac.h:61
IndividualChannelStream::group_len
uint8_t group_len[8]
Definition: aac.h:180
PredictorState
Predictor State.
Definition: aac.h:136
ChannelPosition
ChannelPosition
Definition: aac.h:95
AACContext::fdsp
AVFloatDSPContext * fdsp
Definition: aac.h:334
LongTermPrediction::present
int8_t present
Definition: aac.h:165
AACContext::force_dmono_mode
int force_dmono_mode
0->not dmono, 1->use first channel, 2->use second channel
Definition: aac.h:351
fixed_dsp.h
IndividualChannelStream
Individual Channel Stream.
Definition: aac.h:175
MDCT15Context
Definition: mdct15.h:30
TemporalNoiseShaping::coef
INTFLOAT coef[8][4][TNS_MAX_ORDER]
Definition: aac.h:206
IndividualChannelStream::swb_offset
const uint16_t * swb_offset
table of offsets to the lowest spectral coefficient of a scalefactor band, sfb, for a particular wind...
Definition: aac.h:182
AACContext::warned_num_aac_frames
int warned_num_aac_frames
Definition: aac.h:358
INTENSITY_BT
@ INTENSITY_BT
Scalefactor data are intensity stereo positions (in phase).
Definition: aac.h:90
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
ChannelElement::is_mask
uint8_t is_mask[128]
Set if intensity stereo is used (used by encoder)
Definition: aac.h:283
SingleChannelElement::is_ener
float is_ener[128]
Intensity stereo pos (used by encoder)
Definition: aac.h:260
IndividualChannelStream::num_window_groups
int num_window_groups
Definition: aac.h:179
AACContext::mdct480
MDCT15Context * mdct480
Definition: aac.h:332
AAC_CHANNEL_SIDE
@ AAC_CHANNEL_SIDE
Definition: aac.h:98
AACContext::frame
AVFrame * frame
Definition: aac.h:297
src
#define src
Definition: vp8dsp.c:255
LongTermPrediction::coef_idx
int coef_idx
Definition: aac.h:167
IndividualChannelStream::predictor_present
int predictor_present
Definition: aac.h:187
DynamicRangeControl::band_top
int band_top[17]
Indicates the top of the i-th DRC band in units of 4 spectral lines.
Definition: aac.h:219
AACContext::che
ChannelElement * che[4][MAX_ELEM_ID]
Definition: aac.h:306
AAC_CHANNEL_FRONT
@ AAC_CHANNEL_FRONT
Definition: aac.h:97
SingleChannelElement::predictor_state
PredictorState predictor_state[MAX_PREDICTORS]
Definition: aac.h:269
PredictorState::k1
AAC_FLOAT k1
Definition: aac.h:143
TNS_MAX_ORDER
#define TNS_MAX_ORDER
Definition: aac.h:51
AAC_CHANNEL_OFF
@ AAC_CHANNEL_OFF
Definition: aac.h:96
PredictorState::r1
AAC_FLOAT r1
Definition: aac.h:142
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
SingleChannelElement::band_type_run_end
int band_type_run_end[120]
band type run end points
Definition: aac.h:255
SingleChannelElement::sf_idx
int sf_idx[128]
scalefactor indices (used by encoder)
Definition: aac.h:257
float_dsp.h
OutputConfiguration::layout_map_tags
int layout_map_tags
Definition: aac.h:127
OutputConfiguration::layout_map
uint8_t layout_map[MAX_ELEM_ID *4][3]
Definition: aac.h:126
AACContext::apply_tns
void(* apply_tns)(INTFLOAT coef[1024], TemporalNoiseShaping *tns, IndividualChannelStream *ics, int decode)
Definition: aac.h:366
SingleChannelElement::lcoeffs
AAC_FLOAT lcoeffs[1024]
MDCT of LTP coefficients (used by encoder)
Definition: aac.h:267
AACContext::tags_mapped
int tags_mapped
Definition: aac.h:308
AACContext::avctx
AVCodecContext * avctx
Definition: aac.h:296
ChannelElement::ch
SingleChannelElement ch[2]
Definition: aac.h:285
ONLY_LONG_SEQUENCE
@ ONLY_LONG_SEQUENCE
Definition: aac.h:77
TYPE_END
@ TYPE_END
Definition: aac.h:64
AACContext::warned_remapping_once
int warned_remapping_once
Definition: aac.h:309
TemporalNoiseShaping::n_filt
int n_filt[8]
Definition: aac.h:201
BandType
BandType
Definition: aac.h:83
AACContext::mdct120
MDCT15Context * mdct120
Definition: aac.h:331
ESC_BT
@ ESC_BT
Spectral data are coded with an escape sequence.
Definition: aac.h:86
DynamicRangeControl::prog_ref_level
int prog_ref_level
A reference level for the long-term program audio level for all channels combined.
Definition: aac.h:220
SpectralBandReplication
Spectral Band Replication.
Definition: sbr.h:142
OCStatus
OCStatus
Output configuration status.
Definition: aac.h:116
AVFloatDSPContext
Definition: float_dsp.h:24
OutputConfiguration
Definition: aac.h:124
ChannelElement::common_window
int common_window
Set if channels share a common 'IndividualChannelStream' in bitstream.
Definition: aac.h:279
SingleChannelElement::prcoeffs
AAC_FLOAT prcoeffs[1024]
Main prediction coefs (used by encoder)
Definition: aac.h:268
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
MAX_CHANNELS
#define MAX_CHANNELS
Definition: aac.h:48
ChannelElement::ms_mask
uint8_t ms_mask[128]
Set if mid/side stereo is used for each scalefactor window band.
Definition: aac.h:282
DynamicRangeControl::dyn_rng_ctl
int dyn_rng_ctl[17]
DRC magnitude information.
Definition: aac.h:215
EXT_FILL_DATA
@ EXT_FILL_DATA
Definition: aac.h:69
SingleChannelElement::pns_ener
float pns_ener[128]
Noise energy values (used by encoder)
Definition: aac.h:261
OC_GLOBAL_HDR
@ OC_GLOBAL_HDR
Output configuration set in a global header but not yet locked.
Definition: aac.h:120
DECLARE_ALIGNED
#define DECLARE_ALIGNED(n, t, v)
Definition: mem.h:116
AACContext::mdct960
MDCT15Context * mdct960
Definition: aac.h:333
FFTContext
Definition: fft.h:75
AACContext::mdct_ltp
FFTContext mdct_ltp
Definition: aac.h:327
BETWEEN_TNS_AND_IMDCT
@ BETWEEN_TNS_AND_IMDCT
Definition: aac.h:109
RawDataBlockType
RawDataBlockType
Definition: aac.h:56
SingleChannelElement
Single Channel Element - used for both SCE and LFE elements.
Definition: aac.h:249
IndividualChannelStream::num_windows
int num_windows
Definition: aac.h:185
ChannelElement::sbr
SpectralBandReplication sbr
Definition: aac.h:288
LONG_STOP_SEQUENCE
@ LONG_STOP_SEQUENCE
Definition: aac.h:80
OutputConfiguration::channel_layout
uint64_t channel_layout
Definition: aac.h:129
ChannelElement
channel element - generic struct for SCE/CPE/CCE/LFE
Definition: aac.h:276
PredictorState::x_est
AAC_FLOAT x_est
Definition: aac.h:144
TYPE_LFE
@ TYPE_LFE
Definition: aac.h:60
LongTermPrediction::lag
int16_t lag
Definition: aac.h:166
TYPE_SCE
@ TYPE_SCE
Definition: aac.h:57
AACContext::oc
OutputConfiguration oc[2]
Definition: aac.h:357
len
int len
Definition: vorbis_enc_data.h:426
IndividualChannelStream::tns_max_bands
int tns_max_bands
Definition: aac.h:186
OC_TRIAL_PCE
@ OC_TRIAL_PCE
Output configuration under trial specified by an inband PCE.
Definition: aac.h:118
AACContext::che_drc
DynamicRangeControl che_drc
Definition: aac.h:300
avcodec.h
AAC_CHANNEL_LFE
@ AAC_CHANNEL_LFE
Definition: aac.h:100
DynamicRangeControl::pce_instance_tag
int pce_instance_tag
Indicates with which program the DRC info is associated.
Definition: aac.h:213
SingleChannelElement::sf
INTFLOAT sf[120]
scalefactors
Definition: aac.h:256
AACContext::output_element
SingleChannelElement * output_element[MAX_CHANNELS]
Points to each SingleChannelElement.
Definition: aac.h:343
RESERVED_BT
@ RESERVED_BT
Band types following are encoded differently from others.
Definition: aac.h:87
LONG_START_SEQUENCE
@ LONG_START_SEQUENCE
Definition: aac.h:78
AACContext::update_ltp
void(* update_ltp)(AACContext *ac, SingleChannelElement *sce)
Definition: aac.h:370
ChannelCoupling::ch_select
int ch_select[8]
[0] shared list of gains; [1] list of gains for right channel; [2] list of gains for left channel; [3...
Definition: aac.h:240
SingleChannelElement::tns
TemporalNoiseShaping tns
Definition: aac.h:251
AACContext::warned_71_wide
unsigned warned_71_wide
Definition: aac.h:360
EXT_SBR_DATA_CRC
@ EXT_SBR_DATA_CRC
Definition: aac.h:73
fft.h
AVCodecContext
main external API structure.
Definition: avcodec.h:383
LongTermPrediction
Long Term Prediction.
Definition: aac.h:164
EXT_SBR_DATA
@ EXT_SBR_DATA
Definition: aac.h:72
ff_aacdec_init_mips
void ff_aacdec_init_mips(AACContext *c)
Definition: aacdec_mips.c:434
IndividualChannelStream::window_sequence
enum WindowSequence window_sequence[2]
Definition: aac.h:177
FIRST_PAIR_BT
@ FIRST_PAIR_BT
This and later band types encode two values (rather than four) with one code word.
Definition: aac.h:85
TemporalNoiseShaping
Temporal Noise Shaping.
Definition: aac.h:199
ChannelCoupling::gain
INTFLOAT gain[16][120]
Definition: aac.h:243
ChannelElement::is_mode
uint8_t is_mode
Set if any bands have been encoded using intensity stereo (used by encoder)
Definition: aac.h:281
DynamicRangeControl::band_incr
int band_incr
Number of DRC bands greater than 1 having DRC info.
Definition: aac.h:217
AACContext::buf_mdct
INTFLOAT buf_mdct[1024]
Definition: aac.h:317
OutputConfiguration::m4ac
MPEG4AudioConfig m4ac
Definition: aac.h:125
TYPE_CCE
@ TYPE_CCE
Definition: aac.h:59
PredictorState::cor1
AAC_FLOAT cor1
Definition: aac.h:138
AACContext::windowing_and_mdct_ltp
void(* windowing_and_mdct_ltp)(AACContext *ac, INTFLOAT *out, INTFLOAT *in, IndividualChannelStream *ics)
Definition: aac.h:368
AAC_FLOAT
float AAC_FLOAT
Definition: aac_defines.h:90
DynamicRangeControl::dyn_rng_sgn
int dyn_rng_sgn[17]
DRC sign information; 0 - positive, 1 - negative.
Definition: aac.h:214
ExtensionPayloadID
ExtensionPayloadID
Definition: aac.h:67
IndividualChannelStream::window_clipping
uint8_t window_clipping[8]
set if a certain window is near clipping
Definition: aac.h:192
AACContext::mdct_small
FFTContext mdct_small
Definition: aac.h:325
ChannelCoupling
coupling parameters
Definition: aac.h:235
EXT_DATA_ELEMENT
@ EXT_DATA_ELEMENT
Definition: aac.h:70
AACContext
main AAC context
Definition: aac.h:294
aac_defines.h
IndividualChannelStream::max_sfb
uint8_t max_sfb
number of scalefactor bands per group
Definition: aac.h:176
Pulse
Definition: aac.h:225
AAC_CHANNEL_CC
@ AAC_CHANNEL_CC
Definition: aac.h:101
SingleChannelElement::ltp_state
INTFLOAT ltp_state[3072]
time signal for LTP
Definition: aac.h:266
DynamicRangeControl::interpolation_scheme
int interpolation_scheme
Indicates the interpolation scheme used in the SBR QMF domain.
Definition: aac.h:218
AACContext::warned_gain_control
int warned_gain_control
Definition: aac.h:361
WindowSequence
WindowSequence
Definition: aac.h:76
IndividualChannelStream::ltp
LongTermPrediction ltp
Definition: aac.h:181
AACContext::imdct_and_windowing
void(* imdct_and_windowing)(AACContext *ac, SingleChannelElement *sce)
Definition: aac.h:364
SingleChannelElement::band_type
enum BandType band_type[128]
band types
Definition: aac.h:253
IndividualChannelStream::use_kb_window
uint8_t use_kb_window[2]
If set, use Kaiser-Bessel window, otherwise use a sine window.
Definition: aac.h:178
INTFLOAT
float INTFLOAT
Definition: aac_defines.h:86
OutputConfiguration::channels
int channels
Definition: aac.h:128
AACContext::dmono_mode
int dmono_mode
0->not dmono, 1->use first channel, 2->use second channel
Definition: aac.h:352
IndividualChannelStream::predictor_reset_group
int predictor_reset_group
Definition: aac.h:189
IndividualChannelStream::predictor_initialized
int predictor_initialized
Definition: aac.h:188
PredictorState::cor0
AAC_FLOAT cor0
Definition: aac.h:137