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 {
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;
169  int8_t used[MAX_LTP_LONG_SFB];
171 
172 /**
173  * Individual Channel Stream
174  */
175 typedef struct IndividualChannelStream {
176  uint8_t max_sfb; ///< number of scalefactor bands per group
177  enum WindowSequence window_sequence[2];
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];
205  int coef_idx[8][4][TNS_MAX_ORDER];
206  INTFLOAT coef[8][4][TNS_MAX_ORDER];
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)
269  PredictorState predictor_state[MAX_PREDICTORS];
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  */
307  ChannelElement *tag_che_map[4][MAX_ELEM_ID];
310  /** @} */
311 
312  /**
313  * @name temporary aligned temporary buffers
314  * (We do not want to have these on the stack.)
315  * @{
316  */
317  DECLARE_ALIGNED(32, INTFLOAT, buf_mdct)[1024];
318  /** @} */
319 
320  /**
321  * @name Computed / set up during initialization
322  * @{
323  */
328 #if USE_FIXED
329  AVFixedDSPContext *fdsp;
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 */
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 */
int predictor_initialized
Definition: aac.h:188
AVFloatDSPContext * fdsp
Definition: aac.h:334
static void imdct_and_windowing(AACContext *ac, SingleChannelElement *sce)
Conduct IMDCT and windowing.
static void apply_ltp(AACContext *ac, SingleChannelElement *sce)
Apply the long term prediction.
Band types following are encoded differently from others.
Definition: aac.h:87
Definition: aac.h:61
This structure describes decoded (raw) audio or video data.
Definition: frame.h:314
AVCodecContext * avctx
Definition: aac.h:296
Definition: aac.h:225
else temp
Definition: vf_mcdeint.c:256
Definition: aac.h:64
Definition: aac.h:57
Definition: aac.h:58
INTFLOAT * ret
PCM output.
Definition: aac.h:270
int present
Definition: aac.h:277
int common_window
Set if channels share a common &#39;IndividualChannelStream&#39; in bitstream.
Definition: aac.h:279
static void update_ltp(AACContext *ac, SingleChannelElement *sce)
Update the LTP buffer for next frame.
static void vector_pow43(int *coefs, int len)
Definition: aacdec_fixed.c:154
uint64_t channel_layout
Definition: aac.h:129
GLint GLenum type
Definition: opengl_enc.c:104
#define MAX_LTP_LONG_SFB
Definition: aac.h:52
Dynamic Range Control - decoded from the bitstream but not processed further.
Definition: aac.h:212
ChannelPosition
Definition: aac.h:95
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
Spectral data are scaled white noise not coded in the bitstream.
Definition: aac.h:88
Definition: aac.h:59
int band_incr
Number of DRC bands greater than 1 having DRC info.
Definition: aac.h:217
int dmono_mode
0->not dmono, 1->use first channel, 2->use second channel
Definition: aac.h:352
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
float INTFLOAT
Definition: aac_defines.h:88
Definition: aac.h:68
AAC_FLOAT cor0
Definition: aac.h:137
BandType
Definition: aac.h:83
uint8_t
uint8_t layout_map[MAX_ELEM_ID *4][3]
Definition: aac.h:126
AAC_FLOAT var1
Definition: aac.h:140
Output configuration under trial specified by an inband PCE.
Definition: aac.h:118
int warned_960_sbr
Definition: aac.h:359
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: aac.h:60
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
TemporalNoiseShaping tns
Definition: aac.h:251
CouplingPoint
The point during decoding at which channel coupling is applied.
Definition: aac.h:107
int num_coupled
number of target elements
Definition: aac.h:237
FFTContext mdct_ltp
Definition: aac.h:327
#define DECLARE_ALIGNED(n, t, v)
Declare a variable that is aligned in memory.
Definition: mem.h:117
AAC_FLOAT cor1
Definition: aac.h:138
Scalefactor data are intensity stereo positions (in phase).
Definition: aac.h:90
Output configuration set in a global header but not yet locked.
Definition: aac.h:120
int random_state
Definition: aac.h:336
MDCT15Context * mdct480
Definition: aac.h:332
#define src
Definition: vp8dsp.c:255
MPEG4AudioConfig m4ac
Definition: aac.h:125
AAC_FLOAT r1
Definition: aac.h:142
SpectralBandReplication sbr
Definition: aac.h:288
FFTContext mdct_small
Definition: aac.h:325
unsigned int pos
Definition: spdifenc.c:410
ExtensionPayloadID
Definition: aac.h:67
AAC_FLOAT r0
Definition: aac.h:141
Spectral Band Replication definitions and structures.
GLsizei GLsizei * length
Definition: opengl_enc.c:114
uint8_t max_sfb
number of scalefactor bands per group
Definition: aac.h:176
Definition: aac.h:63
WindowSequence
Definition: aac.h:76
int num_swb
number of scalefactor window bands
Definition: aac.h:184
int prog_ref_level
A reference level for the long-term program audio level for all channels combined.
Definition: aac.h:220
Output configuration locked in place.
Definition: aac.h:121
Predictor State.
Definition: aac.h:136
int warned_remapping_once
Definition: aac.h:309
AAC_FLOAT x_est
Definition: aac.h:144
Definition: fft.h:83
int predictor_reset_group
Definition: aac.h:189
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
MDCT15Context * mdct120
Definition: aac.h:331
float AAC_FLOAT
Definition: aac_defines.h:92
FFTContext mdct_ld
Definition: aac.h:326
void ff_aacdec_init_mips(AACContext *c)
Definition: aacdec_mips.c:433
int pce_instance_tag
Indicates with which program the DRC info is associated.
Definition: aac.h:213
static void windowing_and_mdct_ltp(AACContext *ac, INTFLOAT *out, INTFLOAT *in, IndividualChannelStream *ics)
Apply windowing and MDCT to obtain the spectral coefficient from the predicted sample by LTP...
int interpolation_scheme
Indicates the interpolation scheme used in the SBR QMF domain.
Definition: aac.h:218
coupling parameters
Definition: aac.h:235
int tags_mapped
Definition: aac.h:308
MDCT15Context * mdct960
Definition: aac.h:333
int force_dmono_mode
0->not dmono, 1->use first channel, 2->use second channel
Definition: aac.h:351
int is_saved
Set if elements have stored overlap from previous frame.
Definition: aac.h:299
int warned_num_aac_frames
Definition: aac.h:358
Libavcodec external API header.
Temporal Noise Shaping.
Definition: aac.h:199
Long Term Prediction.
Definition: aac.h:164
static void apply_tns(INTFLOAT coef_param[1024], TemporalNoiseShaping *tns, IndividualChannelStream *ics, int decode)
Decode Temporal Noise Shaping filter coefficients and apply all-pole filters; reference: 4...
main external API structure.
Definition: avcodec.h:531
IndividualChannelStream ics
Definition: aac.h:250
#define MAX_PREDICTORS
Definition: aac.h:147
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(const int16_t *) pi >> 8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(const int16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(const int16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(const int32_t *) pi >> 24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(const int32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(const int32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(const float *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(const float *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(const float *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(const double *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(const double *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(const double *) pi *(1U<< 31))))#define SET_CONV_FUNC_GROUP(ofmt, ifmt) static void set_generic_function(AudioConvert *ac){}void ff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, int channels, int sample_rate, int apply_map){AudioConvert *ac;int in_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) return NULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt) > 2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);return NULL;}return ac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}else if(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;else ac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);return ac;}int ff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){int use_generic=1;int len=in->nb_samples;int p;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%d samples - audio_convert: %s to %s (dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
#define MAX_ELEM_ID
Definition: aac.h:49
Describe the class of an AVClass context structure.
Definition: log.h:67
unsigned warned_71_wide
Definition: aac.h:360
Spectral data are coded with an escape sequence.
Definition: aac.h:86
const uint8_t * swb_sizes
table of scalefactor band sizes for a particular window
Definition: aac.h:183
OCStatus
Output configuration status.
Definition: aac.h:116
#define MAX_CHANNELS
Definition: aac.h:48
#define TNS_MAX_ORDER
Definition: aac.h:51
main AAC context
Definition: aac.h:294
LongTermPrediction ltp
Definition: aac.h:181
AAC_FLOAT k1
Definition: aac.h:143
ChannelCoupling coup
Definition: aac.h:287
int ms_mode
Signals mid/side stereo flags coding mode (used by encoder)
Definition: aac.h:280
Output configuration under trial specified by a frame header.
Definition: aac.h:119
uint8_t is_mode
Set if any bands have been encoded using intensity stereo (used by encoder)
Definition: aac.h:281
enum OCStatus status
Definition: aac.h:130
Scalefactor data are intensity stereo positions (out of phase).
Definition: aac.h:89
int16_t lag
Definition: aac.h:166
DynamicRangeControl che_drc
Definition: aac.h:300
AVFrame * frame
Definition: aac.h:297
Single Channel Element - used for both SCE and LFE elements.
Definition: aac.h:249
Definition: aac.h:62
Individual Channel Stream.
Definition: aac.h:175
float clip_avoidance_factor
set if any window is near clipping to the necessary atennuation factor to avoid it ...
Definition: aac.h:193
INTFLOAT coef
Definition: aac.h:168
channel element - generic struct for SCE/CPE/CCE/LFE
Definition: aac.h:276
int start
Definition: aac.h:227
static void subband_scale(int *dst, int *src, int scale, int offset, int len, void *log_context)
Definition: aacdec_fixed.c:168
int warned_gain_control
Definition: aac.h:361
int len
Scalefactors and spectral data are all zero.
Definition: aac.h:84
int num_pulse
Definition: aac.h:226
FILE * out
Definition: movenc.c:54
FFTContext mdct
Definition: aac.h:324
int8_t present
Definition: aac.h:165
Spectral Band Replication.
Definition: sbr.h:142
int layout_map_tags
Definition: aac.h:127
AAC_FLOAT var0
Definition: aac.h:139
Output unconfigured.
Definition: aac.h:117
This and later band types encode two values (rather than four) with one code word.
Definition: aac.h:85
RawDataBlockType
Definition: aac.h:56