3 * Copyright (c) 2005-2006 Oded Shimon ( ods15 ods15 dyndns org )
4 * Copyright (c) 2006-2007 Maxim Gavrilov ( maxim.gavrilov gmail com )
6 * This file is part of FFmpeg.
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.
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.
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
26 * @author Oded Shimon ( ods15 ods15 dyndns org )
27 * @author Maxim Gavrilov ( maxim.gavrilov gmail com )
34 * N (code in SoC repo) gain control
36 * Y window shapes - standard
37 * N window shapes - Low Delay
38 * Y filterbank - standard
39 * N (code in SoC repo) filterbank - Scalable Sample Rate
40 * Y Temporal Noise Shaping
41 * N (code in SoC repo) Long Term Prediction
44 * Y frequency domain prediction
45 * Y Perceptual Noise Substitution
47 * N Scalable Inverse AAC Quantization
48 * N Frequency Selective Switch
50 * Y quantization & coding - AAC
51 * N quantization & coding - TwinVQ
52 * N quantization & coding - BSAC
53 * N AAC Error Resilience tools
54 * N Error Resilience payload syntax
55 * N Error Protection tool
57 * N Silence Compression
60 * N Structured Audio tools
61 * N Structured Audio Sample Bank Format
63 * N Harmonic and Individual Lines plus Noise
64 * N Text-To-Speech Interface
65 * Y Spectral Band Replication
66 * Y (not in this code) Layer-1
67 * Y (not in this code) Layer-2
68 * Y (not in this code) Layer-3
69 * N SinuSoidal Coding (Transient, Sinusoid, Noise)
71 * N Direct Stream Transfer
73 * Note: - HE AAC v1 comprises LC AAC with Spectral Band Replication.
74 * - HE AAC v2 comprises LC AAC with Spectral Band Replication and
88 #include "aacdectab.h"
89 #include "cbrt_tablegen.h"
92 #include "mpeg4audio.h"
93 #include "aacadtsdec.h"
101 # include "arm/aac.h"
109 static VLC vlc_scalefactors;
110 static VLC vlc_spectral[11];
112 static const char overread_err[] = "Input buffer exhausted before END element found\n";
114 static ChannelElement *get_che(AACContext *ac, int type, int elem_id)
116 // For PCE based channel configurations map the channels solely based on tags.
117 if (!ac->m4ac.chan_config) {
118 return ac->tag_che_map[type][elem_id];
120 // For indexed channel configurations map the channels solely based on position.
121 switch (ac->m4ac.chan_config) {
123 if (ac->tags_mapped == 3 && type == TYPE_CPE) {
125 return ac->tag_che_map[TYPE_CPE][elem_id] = ac->che[TYPE_CPE][2];
128 /* Some streams incorrectly code 5.1 audio as SCE[0] CPE[0] CPE[1] SCE[1]
129 instead of SCE[0] CPE[0] CPE[1] LFE[0]. If we seem to have
130 encountered such a stream, transfer the LFE[0] element to the SCE[1]'s mapping */
131 if (ac->tags_mapped == tags_per_config[ac->m4ac.chan_config] - 1 && (type == TYPE_LFE || type == TYPE_SCE)) {
133 return ac->tag_che_map[type][elem_id] = ac->che[TYPE_LFE][0];
136 if (ac->tags_mapped == 2 && type == TYPE_CPE) {
138 return ac->tag_che_map[TYPE_CPE][elem_id] = ac->che[TYPE_CPE][1];
141 if (ac->tags_mapped == 2 && ac->m4ac.chan_config == 4 && type == TYPE_SCE) {
143 return ac->tag_che_map[TYPE_SCE][elem_id] = ac->che[TYPE_SCE][1];
147 if (ac->tags_mapped == (ac->m4ac.chan_config != 2) && type == TYPE_CPE) {
149 return ac->tag_che_map[TYPE_CPE][elem_id] = ac->che[TYPE_CPE][0];
150 } else if (ac->m4ac.chan_config == 2) {
154 if (!ac->tags_mapped && type == TYPE_SCE) {
156 return ac->tag_che_map[TYPE_SCE][elem_id] = ac->che[TYPE_SCE][0];
164 * Check for the channel element in the current channel position configuration.
165 * If it exists, make sure the appropriate element is allocated and map the
166 * channel order to match the internal FFmpeg channel layout.
168 * @param che_pos current channel position configuration
169 * @param type channel element type
170 * @param id channel element id
171 * @param channels count of the number of channels in the configuration
173 * @return Returns error status. 0 - OK, !0 - error
175 static av_cold int che_configure(AACContext *ac,
176 enum ChannelPosition che_pos[4][MAX_ELEM_ID],
180 if (che_pos[type][id]) {
181 if (!ac->che[type][id] && !(ac->che[type][id] = av_mallocz(sizeof(ChannelElement))))
182 return AVERROR(ENOMEM);
183 ff_aac_sbr_ctx_init(&ac->che[type][id]->sbr);
184 if (type != TYPE_CCE) {
185 ac->output_data[(*channels)++] = ac->che[type][id]->ch[0].ret;
186 if (type == TYPE_CPE ||
187 (type == TYPE_SCE && ac->m4ac.ps == 1)) {
188 ac->output_data[(*channels)++] = ac->che[type][id]->ch[1].ret;
192 if (ac->che[type][id])
193 ff_aac_sbr_ctx_close(&ac->che[type][id]->sbr);
194 av_freep(&ac->che[type][id]);
200 * Configure output channel order based on the current program configuration element.
202 * @param che_pos current channel position configuration
203 * @param new_che_pos New channel position configuration - we only do something if it differs from the current one.
205 * @return Returns error status. 0 - OK, !0 - error
207 static av_cold int output_configure(AACContext *ac,
208 enum ChannelPosition che_pos[4][MAX_ELEM_ID],
209 enum ChannelPosition new_che_pos[4][MAX_ELEM_ID],
210 int channel_config, enum OCStatus oc_type)
212 AVCodecContext *avctx = ac->avctx;
213 int i, type, channels = 0, ret;
215 if (new_che_pos != che_pos)
216 memcpy(che_pos, new_che_pos, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));
218 if (channel_config) {
219 for (i = 0; i < tags_per_config[channel_config]; i++) {
220 if ((ret = che_configure(ac, che_pos,
221 aac_channel_layout_map[channel_config - 1][i][0],
222 aac_channel_layout_map[channel_config - 1][i][1],
227 memset(ac->tag_che_map, 0, 4 * MAX_ELEM_ID * sizeof(ac->che[0][0]));
229 avctx->channel_layout = aac_channel_layout[channel_config - 1];
231 /* Allocate or free elements depending on if they are in the
232 * current program configuration.
234 * Set up default 1:1 output mapping.
236 * For a 5.1 stream the output order will be:
237 * [ Center ] [ Front Left ] [ Front Right ] [ LFE ] [ Surround Left ] [ Surround Right ]
240 for (i = 0; i < MAX_ELEM_ID; i++) {
241 for (type = 0; type < 4; type++) {
242 if ((ret = che_configure(ac, che_pos, type, i, &channels)))
247 memcpy(ac->tag_che_map, ac->che, 4 * MAX_ELEM_ID * sizeof(ac->che[0][0]));
249 avctx->channel_layout = 0;
252 avctx->channels = channels;
254 ac->output_configured = oc_type;
260 * Decode an array of 4 bit element IDs, optionally interleaved with a stereo/mono switching bit.
262 * @param cpe_map Stereo (Channel Pair Element) map, NULL if stereo bit is not present.
263 * @param sce_map mono (Single Channel Element) map
264 * @param type speaker type/position for these channels
266 static void decode_channel_map(enum ChannelPosition *cpe_map,
267 enum ChannelPosition *sce_map,
268 enum ChannelPosition type,
269 GetBitContext *gb, int n)
272 enum ChannelPosition *map = cpe_map && get_bits1(gb) ? cpe_map : sce_map; // stereo or mono map
273 map[get_bits(gb, 4)] = type;
278 * Decode program configuration element; reference: table 4.2.
280 * @param new_che_pos New channel position configuration - we only do something if it differs from the current one.
282 * @return Returns error status. 0 - OK, !0 - error
284 static int decode_pce(AACContext *ac, enum ChannelPosition new_che_pos[4][MAX_ELEM_ID],
287 int num_front, num_side, num_back, num_lfe, num_assoc_data, num_cc, sampling_index;
290 skip_bits(gb, 2); // object_type
292 sampling_index = get_bits(gb, 4);
293 if (ac->m4ac.sampling_index != sampling_index)
294 av_log(ac->avctx, AV_LOG_WARNING, "Sample rate index in program config element does not match the sample rate index configured by the container.\n");
296 num_front = get_bits(gb, 4);
297 num_side = get_bits(gb, 4);
298 num_back = get_bits(gb, 4);
299 num_lfe = get_bits(gb, 2);
300 num_assoc_data = get_bits(gb, 3);
301 num_cc = get_bits(gb, 4);
304 skip_bits(gb, 4); // mono_mixdown_tag
306 skip_bits(gb, 4); // stereo_mixdown_tag
309 skip_bits(gb, 3); // mixdown_coeff_index and pseudo_surround
311 decode_channel_map(new_che_pos[TYPE_CPE], new_che_pos[TYPE_SCE], AAC_CHANNEL_FRONT, gb, num_front);
312 decode_channel_map(new_che_pos[TYPE_CPE], new_che_pos[TYPE_SCE], AAC_CHANNEL_SIDE, gb, num_side );
313 decode_channel_map(new_che_pos[TYPE_CPE], new_che_pos[TYPE_SCE], AAC_CHANNEL_BACK, gb, num_back );
314 decode_channel_map(NULL, new_che_pos[TYPE_LFE], AAC_CHANNEL_LFE, gb, num_lfe );
316 skip_bits_long(gb, 4 * num_assoc_data);
318 decode_channel_map(new_che_pos[TYPE_CCE], new_che_pos[TYPE_CCE], AAC_CHANNEL_CC, gb, num_cc );
322 /* comment field, first byte is length */
323 comment_len = get_bits(gb, 8) * 8;
324 if (get_bits_left(gb) < comment_len) {
325 av_log(ac->avctx, AV_LOG_ERROR, overread_err);
328 skip_bits_long(gb, comment_len);
333 * Set up channel positions based on a default channel configuration
334 * as specified in table 1.17.
336 * @param new_che_pos New channel position configuration - we only do something if it differs from the current one.
338 * @return Returns error status. 0 - OK, !0 - error
340 static av_cold int set_default_channel_config(AACContext *ac,
341 enum ChannelPosition new_che_pos[4][MAX_ELEM_ID],
344 if (channel_config < 1 || channel_config > 7) {
345 av_log(ac->avctx, AV_LOG_ERROR, "invalid default channel configuration (%d)\n",
350 /* default channel configurations:
352 * 1ch : front center (mono)
353 * 2ch : L + R (stereo)
354 * 3ch : front center + L + R
355 * 4ch : front center + L + R + back center
356 * 5ch : front center + L + R + back stereo
357 * 6ch : front center + L + R + back stereo + LFE
358 * 7ch : front center + L + R + outer front left + outer front right + back stereo + LFE
361 if (channel_config != 2)
362 new_che_pos[TYPE_SCE][0] = AAC_CHANNEL_FRONT; // front center (or mono)
363 if (channel_config > 1)
364 new_che_pos[TYPE_CPE][0] = AAC_CHANNEL_FRONT; // L + R (or stereo)
365 if (channel_config == 4)
366 new_che_pos[TYPE_SCE][1] = AAC_CHANNEL_BACK; // back center
367 if (channel_config > 4)
368 new_che_pos[TYPE_CPE][(channel_config == 7) + 1]
369 = AAC_CHANNEL_BACK; // back stereo
370 if (channel_config > 5)
371 new_che_pos[TYPE_LFE][0] = AAC_CHANNEL_LFE; // LFE
372 if (channel_config == 7)
373 new_che_pos[TYPE_CPE][1] = AAC_CHANNEL_FRONT; // outer front left + outer front right
379 * Decode GA "General Audio" specific configuration; reference: table 4.1.
381 * @return Returns error status. 0 - OK, !0 - error
383 static int decode_ga_specific_config(AACContext *ac, GetBitContext *gb,
386 enum ChannelPosition new_che_pos[4][MAX_ELEM_ID];
387 int extension_flag, ret;
389 if (get_bits1(gb)) { // frameLengthFlag
390 av_log_missing_feature(ac->avctx, "960/120 MDCT window is", 1);
394 if (get_bits1(gb)) // dependsOnCoreCoder
395 skip_bits(gb, 14); // coreCoderDelay
396 extension_flag = get_bits1(gb);
398 if (ac->m4ac.object_type == AOT_AAC_SCALABLE ||
399 ac->m4ac.object_type == AOT_ER_AAC_SCALABLE)
400 skip_bits(gb, 3); // layerNr
402 memset(new_che_pos, 0, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));
403 if (channel_config == 0) {
404 skip_bits(gb, 4); // element_instance_tag
405 if ((ret = decode_pce(ac, new_che_pos, gb)))
408 if ((ret = set_default_channel_config(ac, new_che_pos, channel_config)))
411 if ((ret = output_configure(ac, ac->che_pos, new_che_pos, channel_config, OC_GLOBAL_HDR)))
414 if (extension_flag) {
415 switch (ac->m4ac.object_type) {
417 skip_bits(gb, 5); // numOfSubFrame
418 skip_bits(gb, 11); // layer_length
422 case AOT_ER_AAC_SCALABLE:
424 skip_bits(gb, 3); /* aacSectionDataResilienceFlag
425 * aacScalefactorDataResilienceFlag
426 * aacSpectralDataResilienceFlag
430 skip_bits1(gb); // extensionFlag3 (TBD in version 3)
436 * Decode audio specific configuration; reference: table 1.13.
438 * @param data pointer to AVCodecContext extradata
439 * @param data_size size of AVCCodecContext extradata
441 * @return Returns error status. 0 - OK, !0 - error
443 static int decode_audio_specific_config(AACContext *ac, void *data,
449 init_get_bits(&gb, data, data_size * 8);
451 if ((i = ff_mpeg4audio_get_config(&ac->m4ac, data, data_size)) < 0)
453 if (ac->m4ac.sampling_index > 12) {
454 av_log(ac->avctx, AV_LOG_ERROR, "invalid sampling rate index %d\n", ac->m4ac.sampling_index);
457 if (ac->m4ac.sbr == 1 && ac->m4ac.ps == -1)
460 skip_bits_long(&gb, i);
462 switch (ac->m4ac.object_type) {
465 if (decode_ga_specific_config(ac, &gb, ac->m4ac.chan_config))
469 av_log(ac->avctx, AV_LOG_ERROR, "Audio object type %s%d is not supported.\n",
470 ac->m4ac.sbr == 1? "SBR+" : "", ac->m4ac.object_type);
477 * linear congruential pseudorandom number generator
479 * @param previous_val pointer to the current state of the generator
481 * @return Returns a 32-bit pseudorandom integer
483 static av_always_inline int lcg_random(int previous_val)
485 return previous_val * 1664525 + 1013904223;
488 static av_always_inline void reset_predict_state(PredictorState *ps)
498 static void reset_all_predictors(PredictorState *ps)
501 for (i = 0; i < MAX_PREDICTORS; i++)
502 reset_predict_state(&ps[i]);
505 static void reset_predictor_group(PredictorState *ps, int group_num)
508 for (i = group_num - 1; i < MAX_PREDICTORS; i += 30)
509 reset_predict_state(&ps[i]);
512 #define AAC_INIT_VLC_STATIC(num, size) \
513 INIT_VLC_STATIC(&vlc_spectral[num], 8, ff_aac_spectral_sizes[num], \
514 ff_aac_spectral_bits[num], sizeof( ff_aac_spectral_bits[num][0]), sizeof( ff_aac_spectral_bits[num][0]), \
515 ff_aac_spectral_codes[num], sizeof(ff_aac_spectral_codes[num][0]), sizeof(ff_aac_spectral_codes[num][0]), \
518 static av_cold int aac_decode_init(AVCodecContext *avctx)
520 AACContext *ac = avctx->priv_data;
523 ac->m4ac.sample_rate = avctx->sample_rate;
525 if (avctx->extradata_size > 0) {
526 if (decode_audio_specific_config(ac, avctx->extradata, avctx->extradata_size))
530 avctx->sample_fmt = SAMPLE_FMT_S16;
532 AAC_INIT_VLC_STATIC( 0, 304);
533 AAC_INIT_VLC_STATIC( 1, 270);
534 AAC_INIT_VLC_STATIC( 2, 550);
535 AAC_INIT_VLC_STATIC( 3, 300);
536 AAC_INIT_VLC_STATIC( 4, 328);
537 AAC_INIT_VLC_STATIC( 5, 294);
538 AAC_INIT_VLC_STATIC( 6, 306);
539 AAC_INIT_VLC_STATIC( 7, 268);
540 AAC_INIT_VLC_STATIC( 8, 510);
541 AAC_INIT_VLC_STATIC( 9, 366);
542 AAC_INIT_VLC_STATIC(10, 462);
546 dsputil_init(&ac->dsp, avctx);
548 ac->random_state = 0x1f2e3d4c;
550 // -1024 - Compensate wrong IMDCT method.
551 // 32768 - Required to scale values to the correct range for the bias method
552 // for float to int16 conversion.
554 if (ac->dsp.float_to_int16_interleave == ff_float_to_int16_interleave_c) {
555 ac->add_bias = 385.0f;
556 ac->sf_scale = 1. / (-1024. * 32768.);
560 ac->sf_scale = 1. / -1024.;
566 INIT_VLC_STATIC(&vlc_scalefactors,7,FF_ARRAY_ELEMS(ff_aac_scalefactor_code),
567 ff_aac_scalefactor_bits, sizeof(ff_aac_scalefactor_bits[0]), sizeof(ff_aac_scalefactor_bits[0]),
568 ff_aac_scalefactor_code, sizeof(ff_aac_scalefactor_code[0]), sizeof(ff_aac_scalefactor_code[0]),
571 ff_mdct_init(&ac->mdct, 11, 1, 1.0);
572 ff_mdct_init(&ac->mdct_small, 8, 1, 1.0);
573 // window initialization
574 ff_kbd_window_init(ff_aac_kbd_long_1024, 4.0, 1024);
575 ff_kbd_window_init(ff_aac_kbd_short_128, 6.0, 128);
576 ff_init_ff_sine_windows(10);
577 ff_init_ff_sine_windows( 7);
585 * Skip data_stream_element; reference: table 4.10.
587 static int skip_data_stream_element(AACContext *ac, GetBitContext *gb)
589 int byte_align = get_bits1(gb);
590 int count = get_bits(gb, 8);
592 count += get_bits(gb, 8);
596 if (get_bits_left(gb) < 8 * count) {
597 av_log(ac->avctx, AV_LOG_ERROR, overread_err);
600 skip_bits_long(gb, 8 * count);
604 static int decode_prediction(AACContext *ac, IndividualChannelStream *ics,
609 ics->predictor_reset_group = get_bits(gb, 5);
610 if (ics->predictor_reset_group == 0 || ics->predictor_reset_group > 30) {
611 av_log(ac->avctx, AV_LOG_ERROR, "Invalid Predictor Reset Group.\n");
615 for (sfb = 0; sfb < FFMIN(ics->max_sfb, ff_aac_pred_sfb_max[ac->m4ac.sampling_index]); sfb++) {
616 ics->prediction_used[sfb] = get_bits1(gb);
622 * Decode Individual Channel Stream info; reference: table 4.6.
624 * @param common_window Channels have independent [0], or shared [1], Individual Channel Stream information.
626 static int decode_ics_info(AACContext *ac, IndividualChannelStream *ics,
627 GetBitContext *gb, int common_window)
630 av_log(ac->avctx, AV_LOG_ERROR, "Reserved bit set.\n");
631 memset(ics, 0, sizeof(IndividualChannelStream));
634 ics->window_sequence[1] = ics->window_sequence[0];
635 ics->window_sequence[0] = get_bits(gb, 2);
636 ics->use_kb_window[1] = ics->use_kb_window[0];
637 ics->use_kb_window[0] = get_bits1(gb);
638 ics->num_window_groups = 1;
639 ics->group_len[0] = 1;
640 if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
642 ics->max_sfb = get_bits(gb, 4);
643 for (i = 0; i < 7; i++) {
645 ics->group_len[ics->num_window_groups - 1]++;
647 ics->num_window_groups++;
648 ics->group_len[ics->num_window_groups - 1] = 1;
651 ics->num_windows = 8;
652 ics->swb_offset = ff_swb_offset_128[ac->m4ac.sampling_index];
653 ics->num_swb = ff_aac_num_swb_128[ac->m4ac.sampling_index];
654 ics->tns_max_bands = ff_tns_max_bands_128[ac->m4ac.sampling_index];
655 ics->predictor_present = 0;
657 ics->max_sfb = get_bits(gb, 6);
658 ics->num_windows = 1;
659 ics->swb_offset = ff_swb_offset_1024[ac->m4ac.sampling_index];
660 ics->num_swb = ff_aac_num_swb_1024[ac->m4ac.sampling_index];
661 ics->tns_max_bands = ff_tns_max_bands_1024[ac->m4ac.sampling_index];
662 ics->predictor_present = get_bits1(gb);
663 ics->predictor_reset_group = 0;
664 if (ics->predictor_present) {
665 if (ac->m4ac.object_type == AOT_AAC_MAIN) {
666 if (decode_prediction(ac, ics, gb)) {
667 memset(ics, 0, sizeof(IndividualChannelStream));
670 } else if (ac->m4ac.object_type == AOT_AAC_LC) {
671 av_log(ac->avctx, AV_LOG_ERROR, "Prediction is not allowed in AAC-LC.\n");
672 memset(ics, 0, sizeof(IndividualChannelStream));
675 av_log_missing_feature(ac->avctx, "Predictor bit set but LTP is", 1);
676 memset(ics, 0, sizeof(IndividualChannelStream));
682 if (ics->max_sfb > ics->num_swb) {
683 av_log(ac->avctx, AV_LOG_ERROR,
684 "Number of scalefactor bands in group (%d) exceeds limit (%d).\n",
685 ics->max_sfb, ics->num_swb);
686 memset(ics, 0, sizeof(IndividualChannelStream));
694 * Decode band types (section_data payload); reference: table 4.46.
696 * @param band_type array of the used band type
697 * @param band_type_run_end array of the last scalefactor band of a band type run
699 * @return Returns error status. 0 - OK, !0 - error
701 static int decode_band_types(AACContext *ac, enum BandType band_type[120],
702 int band_type_run_end[120], GetBitContext *gb,
703 IndividualChannelStream *ics)
706 const int bits = (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) ? 3 : 5;
707 for (g = 0; g < ics->num_window_groups; g++) {
709 while (k < ics->max_sfb) {
710 uint8_t sect_end = k;
712 int sect_band_type = get_bits(gb, 4);
713 if (sect_band_type == 12) {
714 av_log(ac->avctx, AV_LOG_ERROR, "invalid band type\n");
717 while ((sect_len_incr = get_bits(gb, bits)) == (1 << bits) - 1)
718 sect_end += sect_len_incr;
719 sect_end += sect_len_incr;
720 if (get_bits_left(gb) < 0) {
721 av_log(ac->avctx, AV_LOG_ERROR, overread_err);
724 if (sect_end > ics->max_sfb) {
725 av_log(ac->avctx, AV_LOG_ERROR,
726 "Number of bands (%d) exceeds limit (%d).\n",
727 sect_end, ics->max_sfb);
730 for (; k < sect_end; k++) {
731 band_type [idx] = sect_band_type;
732 band_type_run_end[idx++] = sect_end;
740 * Decode scalefactors; reference: table 4.47.
742 * @param global_gain first scalefactor value as scalefactors are differentially coded
743 * @param band_type array of the used band type
744 * @param band_type_run_end array of the last scalefactor band of a band type run
745 * @param sf array of scalefactors or intensity stereo positions
747 * @return Returns error status. 0 - OK, !0 - error
749 static int decode_scalefactors(AACContext *ac, float sf[120], GetBitContext *gb,
750 unsigned int global_gain,
751 IndividualChannelStream *ics,
752 enum BandType band_type[120],
753 int band_type_run_end[120])
755 const int sf_offset = ac->sf_offset + (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE ? 12 : 0);
757 int offset[3] = { global_gain, global_gain - 90, 100 };
759 static const char *sf_str[3] = { "Global gain", "Noise gain", "Intensity stereo position" };
760 for (g = 0; g < ics->num_window_groups; g++) {
761 for (i = 0; i < ics->max_sfb;) {
762 int run_end = band_type_run_end[idx];
763 if (band_type[idx] == ZERO_BT) {
764 for (; i < run_end; i++, idx++)
766 } else if ((band_type[idx] == INTENSITY_BT) || (band_type[idx] == INTENSITY_BT2)) {
767 for (; i < run_end; i++, idx++) {
768 offset[2] += get_vlc2(gb, vlc_scalefactors.table, 7, 3) - 60;
769 if (offset[2] > 255U) {
770 av_log(ac->avctx, AV_LOG_ERROR,
771 "%s (%d) out of range.\n", sf_str[2], offset[2]);
774 sf[idx] = ff_aac_pow2sf_tab[-offset[2] + 300];
776 } else if (band_type[idx] == NOISE_BT) {
777 for (; i < run_end; i++, idx++) {
778 if (noise_flag-- > 0)
779 offset[1] += get_bits(gb, 9) - 256;
781 offset[1] += get_vlc2(gb, vlc_scalefactors.table, 7, 3) - 60;
782 if (offset[1] > 255U) {
783 av_log(ac->avctx, AV_LOG_ERROR,
784 "%s (%d) out of range.\n", sf_str[1], offset[1]);
787 sf[idx] = -ff_aac_pow2sf_tab[offset[1] + sf_offset + 100];
790 for (; i < run_end; i++, idx++) {
791 offset[0] += get_vlc2(gb, vlc_scalefactors.table, 7, 3) - 60;
792 if (offset[0] > 255U) {
793 av_log(ac->avctx, AV_LOG_ERROR,
794 "%s (%d) out of range.\n", sf_str[0], offset[0]);
797 sf[idx] = -ff_aac_pow2sf_tab[ offset[0] + sf_offset];
806 * Decode pulse data; reference: table 4.7.
808 static int decode_pulses(Pulse *pulse, GetBitContext *gb,
809 const uint16_t *swb_offset, int num_swb)
812 pulse->num_pulse = get_bits(gb, 2) + 1;
813 pulse_swb = get_bits(gb, 6);
814 if (pulse_swb >= num_swb)
816 pulse->pos[0] = swb_offset[pulse_swb];
817 pulse->pos[0] += get_bits(gb, 5);
818 if (pulse->pos[0] > 1023)
820 pulse->amp[0] = get_bits(gb, 4);
821 for (i = 1; i < pulse->num_pulse; i++) {
822 pulse->pos[i] = get_bits(gb, 5) + pulse->pos[i - 1];
823 if (pulse->pos[i] > 1023)
825 pulse->amp[i] = get_bits(gb, 4);
831 * Decode Temporal Noise Shaping data; reference: table 4.48.
833 * @return Returns error status. 0 - OK, !0 - error
835 static int decode_tns(AACContext *ac, TemporalNoiseShaping *tns,
836 GetBitContext *gb, const IndividualChannelStream *ics)
838 int w, filt, i, coef_len, coef_res, coef_compress;
839 const int is8 = ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE;
840 const int tns_max_order = is8 ? 7 : ac->m4ac.object_type == AOT_AAC_MAIN ? 20 : 12;
841 for (w = 0; w < ics->num_windows; w++) {
842 if ((tns->n_filt[w] = get_bits(gb, 2 - is8))) {
843 coef_res = get_bits1(gb);
845 for (filt = 0; filt < tns->n_filt[w]; filt++) {
847 tns->length[w][filt] = get_bits(gb, 6 - 2 * is8);
849 if ((tns->order[w][filt] = get_bits(gb, 5 - 2 * is8)) > tns_max_order) {
850 av_log(ac->avctx, AV_LOG_ERROR, "TNS filter order %d is greater than maximum %d.\n",
851 tns->order[w][filt], tns_max_order);
852 tns->order[w][filt] = 0;
855 if (tns->order[w][filt]) {
856 tns->direction[w][filt] = get_bits1(gb);
857 coef_compress = get_bits1(gb);
858 coef_len = coef_res + 3 - coef_compress;
859 tmp2_idx = 2 * coef_compress + coef_res;
861 for (i = 0; i < tns->order[w][filt]; i++)
862 tns->coef[w][filt][i] = tns_tmp2_map[tmp2_idx][get_bits(gb, coef_len)];
871 * Decode Mid/Side data; reference: table 4.54.
873 * @param ms_present Indicates mid/side stereo presence. [0] mask is all 0s;
874 * [1] mask is decoded from bitstream; [2] mask is all 1s;
875 * [3] reserved for scalable AAC
877 static void decode_mid_side_stereo(ChannelElement *cpe, GetBitContext *gb,
881 if (ms_present == 1) {
882 for (idx = 0; idx < cpe->ch[0].ics.num_window_groups * cpe->ch[0].ics.max_sfb; idx++)
883 cpe->ms_mask[idx] = get_bits1(gb);
884 } else if (ms_present == 2) {
885 memset(cpe->ms_mask, 1, cpe->ch[0].ics.num_window_groups * cpe->ch[0].ics.max_sfb * sizeof(cpe->ms_mask[0]));
890 static inline float *VMUL2(float *dst, const float *v, unsigned idx,
894 *dst++ = v[idx & 15] * s;
895 *dst++ = v[idx>>4 & 15] * s;
901 static inline float *VMUL4(float *dst, const float *v, unsigned idx,
905 *dst++ = v[idx & 3] * s;
906 *dst++ = v[idx>>2 & 3] * s;
907 *dst++ = v[idx>>4 & 3] * s;
908 *dst++ = v[idx>>6 & 3] * s;
914 static inline float *VMUL2S(float *dst, const float *v, unsigned idx,
915 unsigned sign, const float *scale)
917 union float754 s0, s1;
919 s0.f = s1.f = *scale;
920 s0.i ^= sign >> 1 << 31;
923 *dst++ = v[idx & 15] * s0.f;
924 *dst++ = v[idx>>4 & 15] * s1.f;
931 static inline float *VMUL4S(float *dst, const float *v, unsigned idx,
932 unsigned sign, const float *scale)
934 unsigned nz = idx >> 12;
935 union float754 s = { .f = *scale };
938 t.i = s.i ^ (sign & 1<<31);
939 *dst++ = v[idx & 3] * t.f;
941 sign <<= nz & 1; nz >>= 1;
942 t.i = s.i ^ (sign & 1<<31);
943 *dst++ = v[idx>>2 & 3] * t.f;
945 sign <<= nz & 1; nz >>= 1;
946 t.i = s.i ^ (sign & 1<<31);
947 *dst++ = v[idx>>4 & 3] * t.f;
949 sign <<= nz & 1; nz >>= 1;
950 t.i = s.i ^ (sign & 1<<31);
951 *dst++ = v[idx>>6 & 3] * t.f;
958 * Decode spectral data; reference: table 4.50.
959 * Dequantize and scale spectral data; reference: 4.6.3.3.
961 * @param coef array of dequantized, scaled spectral data
962 * @param sf array of scalefactors or intensity stereo positions
963 * @param pulse_present set if pulses are present
964 * @param pulse pointer to pulse data struct
965 * @param band_type array of the used band type
967 * @return Returns error status. 0 - OK, !0 - error
969 static int decode_spectrum_and_dequant(AACContext *ac, float coef[1024],
970 GetBitContext *gb, const float sf[120],
971 int pulse_present, const Pulse *pulse,
972 const IndividualChannelStream *ics,
973 enum BandType band_type[120])
975 int i, k, g, idx = 0;
976 const int c = 1024 / ics->num_windows;
977 const uint16_t *offsets = ics->swb_offset;
978 float *coef_base = coef;
980 for (g = 0; g < ics->num_windows; g++)
981 memset(coef + g * 128 + offsets[ics->max_sfb], 0, sizeof(float) * (c - offsets[ics->max_sfb]));
983 for (g = 0; g < ics->num_window_groups; g++) {
984 unsigned g_len = ics->group_len[g];
986 for (i = 0; i < ics->max_sfb; i++, idx++) {
987 const unsigned cbt_m1 = band_type[idx] - 1;
988 float *cfo = coef + offsets[i];
989 int off_len = offsets[i + 1] - offsets[i];
992 if (cbt_m1 >= INTENSITY_BT2 - 1) {
993 for (group = 0; group < g_len; group++, cfo+=128) {
994 memset(cfo, 0, off_len * sizeof(float));
996 } else if (cbt_m1 == NOISE_BT - 1) {
997 for (group = 0; group < g_len; group++, cfo+=128) {
1001 for (k = 0; k < off_len; k++) {
1002 ac->random_state = lcg_random(ac->random_state);
1003 cfo[k] = ac->random_state;
1006 band_energy = ac->dsp.scalarproduct_float(cfo, cfo, off_len);
1007 scale = sf[idx] / sqrtf(band_energy);
1008 ac->dsp.vector_fmul_scalar(cfo, cfo, scale, off_len);
1011 const float *vq = ff_aac_codebook_vector_vals[cbt_m1];
1012 const uint16_t *cb_vector_idx = ff_aac_codebook_vector_idx[cbt_m1];
1013 VLC_TYPE (*vlc_tab)[2] = vlc_spectral[cbt_m1].table;
1014 OPEN_READER(re, gb);
1016 switch (cbt_m1 >> 1) {
1018 for (group = 0; group < g_len; group++, cfo+=128) {
1026 UPDATE_CACHE(re, gb);
1027 GET_VLC(code, re, gb, vlc_tab, 8, 2);
1028 cb_idx = cb_vector_idx[code];
1029 cf = VMUL4(cf, vq, cb_idx, sf + idx);
1035 for (group = 0; group < g_len; group++, cfo+=128) {
1045 UPDATE_CACHE(re, gb);
1046 GET_VLC(code, re, gb, vlc_tab, 8, 2);
1047 #if MIN_CACHE_BITS < 20
1048 UPDATE_CACHE(re, gb);
1050 cb_idx = cb_vector_idx[code];
1051 nnz = cb_idx >> 8 & 15;
1052 bits = SHOW_UBITS(re, gb, nnz) << (32-nnz);
1053 LAST_SKIP_BITS(re, gb, nnz);
1054 cf = VMUL4S(cf, vq, cb_idx, bits, sf + idx);
1060 for (group = 0; group < g_len; group++, cfo+=128) {
1068 UPDATE_CACHE(re, gb);
1069 GET_VLC(code, re, gb, vlc_tab, 8, 2);
1070 cb_idx = cb_vector_idx[code];
1071 cf = VMUL2(cf, vq, cb_idx, sf + idx);
1078 for (group = 0; group < g_len; group++, cfo+=128) {
1088 UPDATE_CACHE(re, gb);
1089 GET_VLC(code, re, gb, vlc_tab, 8, 2);
1090 cb_idx = cb_vector_idx[code];
1091 nnz = cb_idx >> 8 & 15;
1092 sign = SHOW_UBITS(re, gb, nnz) << (cb_idx >> 12);
1093 LAST_SKIP_BITS(re, gb, nnz);
1094 cf = VMUL2S(cf, vq, cb_idx, sign, sf + idx);
1100 for (group = 0; group < g_len; group++, cfo+=128) {
1102 uint32_t *icf = (uint32_t *) cf;
1112 UPDATE_CACHE(re, gb);
1113 GET_VLC(code, re, gb, vlc_tab, 8, 2);
1121 cb_idx = cb_vector_idx[code];
1124 bits = SHOW_UBITS(re, gb, nnz) << (32-nnz);
1125 LAST_SKIP_BITS(re, gb, nnz);
1127 for (j = 0; j < 2; j++) {
1131 /* The total length of escape_sequence must be < 22 bits according
1132 to the specification (i.e. max is 111111110xxxxxxxxxxxx). */
1133 UPDATE_CACHE(re, gb);
1134 b = GET_CACHE(re, gb);
1135 b = 31 - av_log2(~b);
1138 av_log(ac->avctx, AV_LOG_ERROR, "error in spectral data, ESC overflow\n");
1142 #if MIN_CACHE_BITS < 21
1143 LAST_SKIP_BITS(re, gb, b + 1);
1144 UPDATE_CACHE(re, gb);
1146 SKIP_BITS(re, gb, b + 1);
1149 n = (1 << b) + SHOW_UBITS(re, gb, b);
1150 LAST_SKIP_BITS(re, gb, b);
1151 *icf++ = cbrt_tab[n] | (bits & 1<<31);
1154 unsigned v = ((const uint32_t*)vq)[cb_idx & 15];
1155 *icf++ = (bits & 1<<31) | v;
1162 ac->dsp.vector_fmul_scalar(cfo, cfo, sf[idx], off_len);
1166 CLOSE_READER(re, gb);
1172 if (pulse_present) {
1174 for (i = 0; i < pulse->num_pulse; i++) {
1175 float co = coef_base[ pulse->pos[i] ];
1176 while (offsets[idx + 1] <= pulse->pos[i])
1178 if (band_type[idx] != NOISE_BT && sf[idx]) {
1179 float ico = -pulse->amp[i];
1182 ico = co / sqrtf(sqrtf(fabsf(co))) + (co > 0 ? -ico : ico);
1184 coef_base[ pulse->pos[i] ] = cbrtf(fabsf(ico)) * ico * sf[idx];
1191 static av_always_inline float flt16_round(float pf)
1195 tmp.i = (tmp.i + 0x00008000U) & 0xFFFF0000U;
1199 static av_always_inline float flt16_even(float pf)
1203 tmp.i = (tmp.i + 0x00007FFFU + (tmp.i & 0x00010000U >> 16)) & 0xFFFF0000U;
1207 static av_always_inline float flt16_trunc(float pf)
1211 pun.i &= 0xFFFF0000U;
1215 static av_always_inline void predict(PredictorState *ps, float *coef,
1216 float sf_scale, float inv_sf_scale,
1219 const float a = 0.953125; // 61.0 / 64
1220 const float alpha = 0.90625; // 29.0 / 32
1224 float r0 = ps->r0, r1 = ps->r1;
1225 float cor0 = ps->cor0, cor1 = ps->cor1;
1226 float var0 = ps->var0, var1 = ps->var1;
1228 k1 = var0 > 1 ? cor0 * flt16_even(a / var0) : 0;
1229 k2 = var1 > 1 ? cor1 * flt16_even(a / var1) : 0;
1231 pv = flt16_round(k1 * r0 + k2 * r1);
1233 *coef += pv * sf_scale;
1235 e0 = *coef * inv_sf_scale;
1238 ps->cor1 = flt16_trunc(alpha * cor1 + r1 * e1);
1239 ps->var1 = flt16_trunc(alpha * var1 + 0.5f * (r1 * r1 + e1 * e1));
1240 ps->cor0 = flt16_trunc(alpha * cor0 + r0 * e0);
1241 ps->var0 = flt16_trunc(alpha * var0 + 0.5f * (r0 * r0 + e0 * e0));
1243 ps->r1 = flt16_trunc(a * (r0 - k1 * e0));
1244 ps->r0 = flt16_trunc(a * e0);
1248 * Apply AAC-Main style frequency domain prediction.
1250 static void apply_prediction(AACContext *ac, SingleChannelElement *sce)
1253 float sf_scale = ac->sf_scale, inv_sf_scale = 1 / ac->sf_scale;
1255 if (!sce->ics.predictor_initialized) {
1256 reset_all_predictors(sce->predictor_state);
1257 sce->ics.predictor_initialized = 1;
1260 if (sce->ics.window_sequence[0] != EIGHT_SHORT_SEQUENCE) {
1261 for (sfb = 0; sfb < ff_aac_pred_sfb_max[ac->m4ac.sampling_index]; sfb++) {
1262 for (k = sce->ics.swb_offset[sfb]; k < sce->ics.swb_offset[sfb + 1]; k++) {
1263 predict(&sce->predictor_state[k], &sce->coeffs[k],
1264 sf_scale, inv_sf_scale,
1265 sce->ics.predictor_present && sce->ics.prediction_used[sfb]);
1268 if (sce->ics.predictor_reset_group)
1269 reset_predictor_group(sce->predictor_state, sce->ics.predictor_reset_group);
1271 reset_all_predictors(sce->predictor_state);
1275 * Decode an individual_channel_stream payload; reference: table 4.44.
1277 * @param common_window Channels have independent [0], or shared [1], Individual Channel Stream information.
1278 * @param scale_flag scalable [1] or non-scalable [0] AAC (Unused until scalable AAC is implemented.)
1280 * @return Returns error status. 0 - OK, !0 - error
1282 static int decode_ics(AACContext *ac, SingleChannelElement *sce,
1283 GetBitContext *gb, int common_window, int scale_flag)
1286 TemporalNoiseShaping *tns = &sce->tns;
1287 IndividualChannelStream *ics = &sce->ics;
1288 float *out = sce->coeffs;
1289 int global_gain, pulse_present = 0;
1291 /* This assignment is to silence a GCC warning about the variable being used
1292 * uninitialized when in fact it always is.
1294 pulse.num_pulse = 0;
1296 global_gain = get_bits(gb, 8);
1298 if (!common_window && !scale_flag) {
1299 if (decode_ics_info(ac, ics, gb, 0) < 0)
1303 if (decode_band_types(ac, sce->band_type, sce->band_type_run_end, gb, ics) < 0)
1305 if (decode_scalefactors(ac, sce->sf, gb, global_gain, ics, sce->band_type, sce->band_type_run_end) < 0)
1310 if ((pulse_present = get_bits1(gb))) {
1311 if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
1312 av_log(ac->avctx, AV_LOG_ERROR, "Pulse tool not allowed in eight short sequence.\n");
1315 if (decode_pulses(&pulse, gb, ics->swb_offset, ics->num_swb)) {
1316 av_log(ac->avctx, AV_LOG_ERROR, "Pulse data corrupt or invalid.\n");
1320 if ((tns->present = get_bits1(gb)) && decode_tns(ac, tns, gb, ics))
1322 if (get_bits1(gb)) {
1323 av_log_missing_feature(ac->avctx, "SSR", 1);
1328 if (decode_spectrum_and_dequant(ac, out, gb, sce->sf, pulse_present, &pulse, ics, sce->band_type) < 0)
1331 if (ac->m4ac.object_type == AOT_AAC_MAIN && !common_window)
1332 apply_prediction(ac, sce);
1338 * Mid/Side stereo decoding; reference: 4.6.8.1.3.
1340 static void apply_mid_side_stereo(AACContext *ac, ChannelElement *cpe)
1342 const IndividualChannelStream *ics = &cpe->ch[0].ics;
1343 float *ch0 = cpe->ch[0].coeffs;
1344 float *ch1 = cpe->ch[1].coeffs;
1345 int g, i, group, idx = 0;
1346 const uint16_t *offsets = ics->swb_offset;
1347 for (g = 0; g < ics->num_window_groups; g++) {
1348 for (i = 0; i < ics->max_sfb; i++, idx++) {
1349 if (cpe->ms_mask[idx] &&
1350 cpe->ch[0].band_type[idx] < NOISE_BT && cpe->ch[1].band_type[idx] < NOISE_BT) {
1351 for (group = 0; group < ics->group_len[g]; group++) {
1352 ac->dsp.butterflies_float(ch0 + group * 128 + offsets[i],
1353 ch1 + group * 128 + offsets[i],
1354 offsets[i+1] - offsets[i]);
1358 ch0 += ics->group_len[g] * 128;
1359 ch1 += ics->group_len[g] * 128;
1364 * intensity stereo decoding; reference: 4.6.8.2.3
1366 * @param ms_present Indicates mid/side stereo presence. [0] mask is all 0s;
1367 * [1] mask is decoded from bitstream; [2] mask is all 1s;
1368 * [3] reserved for scalable AAC
1370 static void apply_intensity_stereo(ChannelElement *cpe, int ms_present)
1372 const IndividualChannelStream *ics = &cpe->ch[1].ics;
1373 SingleChannelElement *sce1 = &cpe->ch[1];
1374 float *coef0 = cpe->ch[0].coeffs, *coef1 = cpe->ch[1].coeffs;
1375 const uint16_t *offsets = ics->swb_offset;
1376 int g, group, i, k, idx = 0;
1379 for (g = 0; g < ics->num_window_groups; g++) {
1380 for (i = 0; i < ics->max_sfb;) {
1381 if (sce1->band_type[idx] == INTENSITY_BT || sce1->band_type[idx] == INTENSITY_BT2) {
1382 const int bt_run_end = sce1->band_type_run_end[idx];
1383 for (; i < bt_run_end; i++, idx++) {
1384 c = -1 + 2 * (sce1->band_type[idx] - 14);
1386 c *= 1 - 2 * cpe->ms_mask[idx];
1387 scale = c * sce1->sf[idx];
1388 for (group = 0; group < ics->group_len[g]; group++)
1389 for (k = offsets[i]; k < offsets[i + 1]; k++)
1390 coef1[group * 128 + k] = scale * coef0[group * 128 + k];
1393 int bt_run_end = sce1->band_type_run_end[idx];
1394 idx += bt_run_end - i;
1398 coef0 += ics->group_len[g] * 128;
1399 coef1 += ics->group_len[g] * 128;
1404 * Decode a channel_pair_element; reference: table 4.4.
1406 * @return Returns error status. 0 - OK, !0 - error
1408 static int decode_cpe(AACContext *ac, GetBitContext *gb, ChannelElement *cpe)
1410 int i, ret, common_window, ms_present = 0;
1412 common_window = get_bits1(gb);
1413 if (common_window) {
1414 if (decode_ics_info(ac, &cpe->ch[0].ics, gb, 1))
1416 i = cpe->ch[1].ics.use_kb_window[0];
1417 cpe->ch[1].ics = cpe->ch[0].ics;
1418 cpe->ch[1].ics.use_kb_window[1] = i;
1419 ms_present = get_bits(gb, 2);
1420 if (ms_present == 3) {
1421 av_log(ac->avctx, AV_LOG_ERROR, "ms_present = 3 is reserved.\n");
1423 } else if (ms_present)
1424 decode_mid_side_stereo(cpe, gb, ms_present);
1426 if ((ret = decode_ics(ac, &cpe->ch[0], gb, common_window, 0)))
1428 if ((ret = decode_ics(ac, &cpe->ch[1], gb, common_window, 0)))
1431 if (common_window) {
1433 apply_mid_side_stereo(ac, cpe);
1434 if (ac->m4ac.object_type == AOT_AAC_MAIN) {
1435 apply_prediction(ac, &cpe->ch[0]);
1436 apply_prediction(ac, &cpe->ch[1]);
1440 apply_intensity_stereo(cpe, ms_present);
1444 static const float cce_scale[] = {
1445 1.09050773266525765921, //2^(1/8)
1446 1.18920711500272106672, //2^(1/4)
1452 * Decode coupling_channel_element; reference: table 4.8.
1454 * @return Returns error status. 0 - OK, !0 - error
1456 static int decode_cce(AACContext *ac, GetBitContext *gb, ChannelElement *che)
1462 SingleChannelElement *sce = &che->ch[0];
1463 ChannelCoupling *coup = &che->coup;
1465 coup->coupling_point = 2 * get_bits1(gb);
1466 coup->num_coupled = get_bits(gb, 3);
1467 for (c = 0; c <= coup->num_coupled; c++) {
1469 coup->type[c] = get_bits1(gb) ? TYPE_CPE : TYPE_SCE;
1470 coup->id_select[c] = get_bits(gb, 4);
1471 if (coup->type[c] == TYPE_CPE) {
1472 coup->ch_select[c] = get_bits(gb, 2);
1473 if (coup->ch_select[c] == 3)
1476 coup->ch_select[c] = 2;
1478 coup->coupling_point += get_bits1(gb) || (coup->coupling_point >> 1);
1480 sign = get_bits(gb, 1);
1481 scale = cce_scale[get_bits(gb, 2)];
1483 if ((ret = decode_ics(ac, sce, gb, 0, 0)))
1486 for (c = 0; c < num_gain; c++) {
1490 float gain_cache = 1.;
1492 cge = coup->coupling_point == AFTER_IMDCT ? 1 : get_bits1(gb);
1493 gain = cge ? get_vlc2(gb, vlc_scalefactors.table, 7, 3) - 60: 0;
1494 gain_cache = powf(scale, -gain);
1496 if (coup->coupling_point == AFTER_IMDCT) {
1497 coup->gain[c][0] = gain_cache;
1499 for (g = 0; g < sce->ics.num_window_groups; g++) {
1500 for (sfb = 0; sfb < sce->ics.max_sfb; sfb++, idx++) {
1501 if (sce->band_type[idx] != ZERO_BT) {
1503 int t = get_vlc2(gb, vlc_scalefactors.table, 7, 3) - 60;
1511 gain_cache = powf(scale, -t) * s;
1514 coup->gain[c][idx] = gain_cache;
1524 * Parse whether channels are to be excluded from Dynamic Range Compression; reference: table 4.53.
1526 * @return Returns number of bytes consumed.
1528 static int decode_drc_channel_exclusions(DynamicRangeControl *che_drc,
1532 int num_excl_chan = 0;
1535 for (i = 0; i < 7; i++)
1536 che_drc->exclude_mask[num_excl_chan++] = get_bits1(gb);
1537 } while (num_excl_chan < MAX_CHANNELS - 7 && get_bits1(gb));
1539 return num_excl_chan / 7;
1543 * Decode dynamic range information; reference: table 4.52.
1545 * @param cnt length of TYPE_FIL syntactic element in bytes
1547 * @return Returns number of bytes consumed.
1549 static int decode_dynamic_range(DynamicRangeControl *che_drc,
1550 GetBitContext *gb, int cnt)
1553 int drc_num_bands = 1;
1556 /* pce_tag_present? */
1557 if (get_bits1(gb)) {
1558 che_drc->pce_instance_tag = get_bits(gb, 4);
1559 skip_bits(gb, 4); // tag_reserved_bits
1563 /* excluded_chns_present? */
1564 if (get_bits1(gb)) {
1565 n += decode_drc_channel_exclusions(che_drc, gb);
1568 /* drc_bands_present? */
1569 if (get_bits1(gb)) {
1570 che_drc->band_incr = get_bits(gb, 4);
1571 che_drc->interpolation_scheme = get_bits(gb, 4);
1573 drc_num_bands += che_drc->band_incr;
1574 for (i = 0; i < drc_num_bands; i++) {
1575 che_drc->band_top[i] = get_bits(gb, 8);
1580 /* prog_ref_level_present? */
1581 if (get_bits1(gb)) {
1582 che_drc->prog_ref_level = get_bits(gb, 7);
1583 skip_bits1(gb); // prog_ref_level_reserved_bits
1587 for (i = 0; i < drc_num_bands; i++) {
1588 che_drc->dyn_rng_sgn[i] = get_bits1(gb);
1589 che_drc->dyn_rng_ctl[i] = get_bits(gb, 7);
1597 * Decode extension data (incomplete); reference: table 4.51.
1599 * @param cnt length of TYPE_FIL syntactic element in bytes
1601 * @return Returns number of bytes consumed
1603 static int decode_extension_payload(AACContext *ac, GetBitContext *gb, int cnt,
1604 ChannelElement *che, enum RawDataBlockType elem_type)
1608 switch (get_bits(gb, 4)) { // extension type
1609 case EXT_SBR_DATA_CRC:
1613 av_log(ac->avctx, AV_LOG_ERROR, "SBR was found before the first channel element.\n");
1615 } else if (!ac->m4ac.sbr) {
1616 av_log(ac->avctx, AV_LOG_ERROR, "SBR signaled to be not-present but was found in the bitstream.\n");
1617 skip_bits_long(gb, 8 * cnt - 4);
1619 } else if (ac->m4ac.sbr == -1 && ac->output_configured == OC_LOCKED) {
1620 av_log(ac->avctx, AV_LOG_ERROR, "Implicit SBR was found with a first occurrence after the first frame.\n");
1621 skip_bits_long(gb, 8 * cnt - 4);
1623 } else if (ac->m4ac.ps == -1 && ac->output_configured < OC_LOCKED && ac->avctx->channels == 1) {
1626 output_configure(ac, ac->che_pos, ac->che_pos, ac->m4ac.chan_config, ac->output_configured);
1630 res = ff_decode_sbr_extension(ac, &che->sbr, gb, crc_flag, cnt, elem_type);
1632 case EXT_DYNAMIC_RANGE:
1633 res = decode_dynamic_range(&ac->che_drc, gb, cnt);
1637 case EXT_DATA_ELEMENT:
1639 skip_bits_long(gb, 8 * cnt - 4);
1646 * Decode Temporal Noise Shaping filter coefficients and apply all-pole filters; reference: 4.6.9.3.
1648 * @param decode 1 if tool is used normally, 0 if tool is used in LTP.
1649 * @param coef spectral coefficients
1651 static void apply_tns(float coef[1024], TemporalNoiseShaping *tns,
1652 IndividualChannelStream *ics, int decode)
1654 const int mmm = FFMIN(ics->tns_max_bands, ics->max_sfb);
1656 int bottom, top, order, start, end, size, inc;
1657 float lpc[TNS_MAX_ORDER];
1659 for (w = 0; w < ics->num_windows; w++) {
1660 bottom = ics->num_swb;
1661 for (filt = 0; filt < tns->n_filt[w]; filt++) {
1663 bottom = FFMAX(0, top - tns->length[w][filt]);
1664 order = tns->order[w][filt];
1669 compute_lpc_coefs(tns->coef[w][filt], order, lpc, 0, 0, 0);
1671 start = ics->swb_offset[FFMIN(bottom, mmm)];
1672 end = ics->swb_offset[FFMIN( top, mmm)];
1673 if ((size = end - start) <= 0)
1675 if (tns->direction[w][filt]) {
1684 for (m = 0; m < size; m++, start += inc)
1685 for (i = 1; i <= FFMIN(m, order); i++)
1686 coef[start] -= coef[start - i * inc] * lpc[i - 1];
1692 * Conduct IMDCT and windowing.
1694 static void imdct_and_windowing(AACContext *ac, SingleChannelElement *sce, float bias)
1696 IndividualChannelStream *ics = &sce->ics;
1697 float *in = sce->coeffs;
1698 float *out = sce->ret;
1699 float *saved = sce->saved;
1700 const float *swindow = ics->use_kb_window[0] ? ff_aac_kbd_short_128 : ff_sine_128;
1701 const float *lwindow_prev = ics->use_kb_window[1] ? ff_aac_kbd_long_1024 : ff_sine_1024;
1702 const float *swindow_prev = ics->use_kb_window[1] ? ff_aac_kbd_short_128 : ff_sine_128;
1703 float *buf = ac->buf_mdct;
1704 float *temp = ac->temp;
1708 if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
1709 for (i = 0; i < 1024; i += 128)
1710 ff_imdct_half(&ac->mdct_small, buf + i, in + i);
1712 ff_imdct_half(&ac->mdct, buf, in);
1714 /* window overlapping
1715 * NOTE: To simplify the overlapping code, all 'meaningless' short to long
1716 * and long to short transitions are considered to be short to short
1717 * transitions. This leaves just two cases (long to long and short to short)
1718 * with a little special sauce for EIGHT_SHORT_SEQUENCE.
1720 if ((ics->window_sequence[1] == ONLY_LONG_SEQUENCE || ics->window_sequence[1] == LONG_STOP_SEQUENCE) &&
1721 (ics->window_sequence[0] == ONLY_LONG_SEQUENCE || ics->window_sequence[0] == LONG_START_SEQUENCE)) {
1722 ac->dsp.vector_fmul_window( out, saved, buf, lwindow_prev, bias, 512);
1724 for (i = 0; i < 448; i++)
1725 out[i] = saved[i] + bias;
1727 if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
1728 ac->dsp.vector_fmul_window(out + 448 + 0*128, saved + 448, buf + 0*128, swindow_prev, bias, 64);
1729 ac->dsp.vector_fmul_window(out + 448 + 1*128, buf + 0*128 + 64, buf + 1*128, swindow, bias, 64);
1730 ac->dsp.vector_fmul_window(out + 448 + 2*128, buf + 1*128 + 64, buf + 2*128, swindow, bias, 64);
1731 ac->dsp.vector_fmul_window(out + 448 + 3*128, buf + 2*128 + 64, buf + 3*128, swindow, bias, 64);
1732 ac->dsp.vector_fmul_window(temp, buf + 3*128 + 64, buf + 4*128, swindow, bias, 64);
1733 memcpy( out + 448 + 4*128, temp, 64 * sizeof(float));
1735 ac->dsp.vector_fmul_window(out + 448, saved + 448, buf, swindow_prev, bias, 64);
1736 for (i = 576; i < 1024; i++)
1737 out[i] = buf[i-512] + bias;
1742 if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
1743 for (i = 0; i < 64; i++)
1744 saved[i] = temp[64 + i] - bias;
1745 ac->dsp.vector_fmul_window(saved + 64, buf + 4*128 + 64, buf + 5*128, swindow, 0, 64);
1746 ac->dsp.vector_fmul_window(saved + 192, buf + 5*128 + 64, buf + 6*128, swindow, 0, 64);
1747 ac->dsp.vector_fmul_window(saved + 320, buf + 6*128 + 64, buf + 7*128, swindow, 0, 64);
1748 memcpy( saved + 448, buf + 7*128 + 64, 64 * sizeof(float));
1749 } else if (ics->window_sequence[0] == LONG_START_SEQUENCE) {
1750 memcpy( saved, buf + 512, 448 * sizeof(float));
1751 memcpy( saved + 448, buf + 7*128 + 64, 64 * sizeof(float));
1752 } else { // LONG_STOP or ONLY_LONG
1753 memcpy( saved, buf + 512, 512 * sizeof(float));
1758 * Apply dependent channel coupling (applied before IMDCT).
1760 * @param index index into coupling gain array
1762 static void apply_dependent_coupling(AACContext *ac,
1763 SingleChannelElement *target,
1764 ChannelElement *cce, int index)
1766 IndividualChannelStream *ics = &cce->ch[0].ics;
1767 const uint16_t *offsets = ics->swb_offset;
1768 float *dest = target->coeffs;
1769 const float *src = cce->ch[0].coeffs;
1770 int g, i, group, k, idx = 0;
1771 if (ac->m4ac.object_type == AOT_AAC_LTP) {
1772 av_log(ac->avctx, AV_LOG_ERROR,
1773 "Dependent coupling is not supported together with LTP\n");
1776 for (g = 0; g < ics->num_window_groups; g++) {
1777 for (i = 0; i < ics->max_sfb; i++, idx++) {
1778 if (cce->ch[0].band_type[idx] != ZERO_BT) {
1779 const float gain = cce->coup.gain[index][idx];
1780 for (group = 0; group < ics->group_len[g]; group++) {
1781 for (k = offsets[i]; k < offsets[i + 1]; k++) {
1783 dest[group * 128 + k] += gain * src[group * 128 + k];
1788 dest += ics->group_len[g] * 128;
1789 src += ics->group_len[g] * 128;
1794 * Apply independent channel coupling (applied after IMDCT).
1796 * @param index index into coupling gain array
1798 static void apply_independent_coupling(AACContext *ac,
1799 SingleChannelElement *target,
1800 ChannelElement *cce, int index)
1803 const float gain = cce->coup.gain[index][0];
1804 const float bias = ac->add_bias;
1805 const float *src = cce->ch[0].ret;
1806 float *dest = target->ret;
1807 const int len = 1024 << (ac->m4ac.sbr == 1);
1809 for (i = 0; i < len; i++)
1810 dest[i] += gain * (src[i] - bias);
1814 * channel coupling transformation interface
1816 * @param apply_coupling_method pointer to (in)dependent coupling function
1818 static void apply_channel_coupling(AACContext *ac, ChannelElement *cc,
1819 enum RawDataBlockType type, int elem_id,
1820 enum CouplingPoint coupling_point,
1821 void (*apply_coupling_method)(AACContext *ac, SingleChannelElement *target, ChannelElement *cce, int index))
1825 for (i = 0; i < MAX_ELEM_ID; i++) {
1826 ChannelElement *cce = ac->che[TYPE_CCE][i];
1829 if (cce && cce->coup.coupling_point == coupling_point) {
1830 ChannelCoupling *coup = &cce->coup;
1832 for (c = 0; c <= coup->num_coupled; c++) {
1833 if (coup->type[c] == type && coup->id_select[c] == elem_id) {
1834 if (coup->ch_select[c] != 1) {
1835 apply_coupling_method(ac, &cc->ch[0], cce, index);
1836 if (coup->ch_select[c] != 0)
1839 if (coup->ch_select[c] != 2)
1840 apply_coupling_method(ac, &cc->ch[1], cce, index++);
1842 index += 1 + (coup->ch_select[c] == 3);
1849 * Convert spectral data to float samples, applying all supported tools as appropriate.
1851 static void spectral_to_sample(AACContext *ac)
1854 float imdct_bias = (ac->m4ac.sbr <= 0) ? ac->add_bias : 0.0f;
1855 for (type = 3; type >= 0; type--) {
1856 for (i = 0; i < MAX_ELEM_ID; i++) {
1857 ChannelElement *che = ac->che[type][i];
1859 if (type <= TYPE_CPE)
1860 apply_channel_coupling(ac, che, type, i, BEFORE_TNS, apply_dependent_coupling);
1861 if (che->ch[0].tns.present)
1862 apply_tns(che->ch[0].coeffs, &che->ch[0].tns, &che->ch[0].ics, 1);
1863 if (che->ch[1].tns.present)
1864 apply_tns(che->ch[1].coeffs, &che->ch[1].tns, &che->ch[1].ics, 1);
1865 if (type <= TYPE_CPE)
1866 apply_channel_coupling(ac, che, type, i, BETWEEN_TNS_AND_IMDCT, apply_dependent_coupling);
1867 if (type != TYPE_CCE || che->coup.coupling_point == AFTER_IMDCT) {
1868 imdct_and_windowing(ac, &che->ch[0], imdct_bias);
1869 if (type == TYPE_CPE) {
1870 imdct_and_windowing(ac, &che->ch[1], imdct_bias);
1872 if (ac->m4ac.sbr > 0) {
1873 ff_sbr_apply(ac, &che->sbr, type, che->ch[0].ret, che->ch[1].ret);
1876 if (type <= TYPE_CCE)
1877 apply_channel_coupling(ac, che, type, i, AFTER_IMDCT, apply_independent_coupling);
1883 static int parse_adts_frame_header(AACContext *ac, GetBitContext *gb)
1886 AACADTSHeaderInfo hdr_info;
1888 size = ff_aac_parse_header(gb, &hdr_info);
1890 if (ac->output_configured != OC_LOCKED && hdr_info.chan_config) {
1891 enum ChannelPosition new_che_pos[4][MAX_ELEM_ID];
1892 memset(new_che_pos, 0, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));
1893 ac->m4ac.chan_config = hdr_info.chan_config;
1894 if (set_default_channel_config(ac, new_che_pos, hdr_info.chan_config))
1896 if (output_configure(ac, ac->che_pos, new_che_pos, hdr_info.chan_config, OC_TRIAL_FRAME))
1898 } else if (ac->output_configured != OC_LOCKED) {
1899 ac->output_configured = OC_NONE;
1901 if (ac->output_configured != OC_LOCKED) {
1905 ac->m4ac.sample_rate = hdr_info.sample_rate;
1906 ac->m4ac.sampling_index = hdr_info.sampling_index;
1907 ac->m4ac.object_type = hdr_info.object_type;
1908 if (!ac->avctx->sample_rate)
1909 ac->avctx->sample_rate = hdr_info.sample_rate;
1910 if (hdr_info.num_aac_frames == 1) {
1911 if (!hdr_info.crc_absent)
1914 av_log_missing_feature(ac->avctx, "More than one AAC RDB per ADTS frame is", 0);
1921 static int aac_decode_frame(AVCodecContext *avctx, void *data,
1922 int *data_size, AVPacket *avpkt)
1924 const uint8_t *buf = avpkt->data;
1925 int buf_size = avpkt->size;
1926 AACContext *ac = avctx->priv_data;
1927 ChannelElement *che = NULL, *che_prev = NULL;
1929 enum RawDataBlockType elem_type, elem_type_prev = TYPE_END;
1930 int err, elem_id, data_size_tmp;
1932 int samples = 0, multiplier;
1935 init_get_bits(&gb, buf, buf_size * 8);
1937 if (show_bits(&gb, 12) == 0xfff) {
1938 if (parse_adts_frame_header(ac, &gb) < 0) {
1939 av_log(avctx, AV_LOG_ERROR, "Error decoding AAC frame header.\n");
1942 if (ac->m4ac.sampling_index > 12) {
1943 av_log(ac->avctx, AV_LOG_ERROR, "invalid sampling rate index %d\n", ac->m4ac.sampling_index);
1948 ac->tags_mapped = 0;
1950 while ((elem_type = get_bits(&gb, 3)) != TYPE_END) {
1951 elem_id = get_bits(&gb, 4);
1953 if (elem_type < TYPE_DSE) {
1954 if (!(che=get_che(ac, elem_type, elem_id))) {
1955 av_log(ac->avctx, AV_LOG_ERROR, "channel element %d.%d is not allocated\n",
1956 elem_type, elem_id);
1962 switch (elem_type) {
1965 err = decode_ics(ac, &che->ch[0], &gb, 0, 0);
1969 err = decode_cpe(ac, &gb, che);
1973 err = decode_cce(ac, &gb, che);
1977 err = decode_ics(ac, &che->ch[0], &gb, 0, 0);
1981 err = skip_data_stream_element(ac, &gb);
1985 enum ChannelPosition new_che_pos[4][MAX_ELEM_ID];
1986 memset(new_che_pos, 0, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));
1987 if ((err = decode_pce(ac, new_che_pos, &gb)))
1989 if (ac->output_configured > OC_TRIAL_PCE)
1990 av_log(avctx, AV_LOG_ERROR,
1991 "Not evaluating a further program_config_element as this construct is dubious at best.\n");
1993 err = output_configure(ac, ac->che_pos, new_che_pos, 0, OC_TRIAL_PCE);
1999 elem_id += get_bits(&gb, 8) - 1;
2000 if (get_bits_left(&gb) < 8 * elem_id) {
2001 av_log(avctx, AV_LOG_ERROR, overread_err);
2005 elem_id -= decode_extension_payload(ac, &gb, elem_id, che_prev, elem_type_prev);
2006 err = 0; /* FIXME */
2010 err = -1; /* should not happen, but keeps compiler happy */
2015 elem_type_prev = elem_type;
2020 if (get_bits_left(&gb) < 3) {
2021 av_log(avctx, AV_LOG_ERROR, overread_err);
2026 spectral_to_sample(ac);
2028 multiplier = (ac->m4ac.sbr == 1) ? ac->m4ac.ext_sample_rate > ac->m4ac.sample_rate : 0;
2029 samples <<= multiplier;
2030 if (ac->output_configured < OC_LOCKED) {
2031 avctx->sample_rate = ac->m4ac.sample_rate << multiplier;
2032 avctx->frame_size = samples;
2035 data_size_tmp = samples * avctx->channels * sizeof(int16_t);
2036 if (*data_size < data_size_tmp) {
2037 av_log(avctx, AV_LOG_ERROR,
2038 "Output buffer too small (%d) or trying to output too many samples (%d) for this frame.\n",
2039 *data_size, data_size_tmp);
2042 *data_size = data_size_tmp;
2045 ac->dsp.float_to_int16_interleave(data, (const float **)ac->output_data, samples, avctx->channels);
2047 if (ac->output_configured)
2048 ac->output_configured = OC_LOCKED;
2050 buf_consumed = (get_bits_count(&gb) + 7) >> 3;
2051 for (buf_offset = buf_consumed; buf_offset < buf_size; buf_offset++)
2052 if (buf[buf_offset])
2055 return buf_size > buf_offset ? buf_consumed : buf_size;
2058 static av_cold int aac_decode_close(AVCodecContext *avctx)
2060 AACContext *ac = avctx->priv_data;
2063 for (i = 0; i < MAX_ELEM_ID; i++) {
2064 for (type = 0; type < 4; type++) {
2065 if (ac->che[type][i])
2066 ff_aac_sbr_ctx_close(&ac->che[type][i]->sbr);
2067 av_freep(&ac->che[type][i]);
2071 ff_mdct_end(&ac->mdct);
2072 ff_mdct_end(&ac->mdct_small);
2076 AVCodec aac_decoder = {
2085 .long_name = NULL_IF_CONFIG_SMALL("Advanced Audio Coding"),
2086 .sample_fmts = (const enum SampleFormat[]) {
2087 SAMPLE_FMT_S16,SAMPLE_FMT_NONE
2089 .channel_layouts = aac_channel_layout,