2 * AAC Spectral Band Replication decoding functions
3 * Copyright (c) 2008-2009 Robert Swain ( rob opendot cl )
4 * Copyright (c) 2009-2010 Alex Converse <alex.converse@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
25 * AAC Spectral Band Replication decoding functions
26 * @author Robert Swain ( rob opendot cl )
32 #include "aacsbrdata.h"
36 #include "libavutil/libm.h"
37 #include "libavutil/avassert.h"
43 #define ENVELOPE_ADJUSTMENT_OFFSET 2
44 #define NOISE_FLOOR_OFFSET 6.0f
52 T_HUFFMAN_ENV_BAL_1_5DB,
53 F_HUFFMAN_ENV_BAL_1_5DB,
56 T_HUFFMAN_ENV_BAL_3_0DB,
57 F_HUFFMAN_ENV_BAL_3_0DB,
58 T_HUFFMAN_NOISE_3_0DB,
59 T_HUFFMAN_NOISE_BAL_3_0DB,
63 * bs_frame_class - frame class of current SBR frame (14496-3 sp04 p98)
76 static VLC vlc_sbr[10];
77 static const int8_t vlc_sbr_lav[10] =
78 { 60, 60, 24, 24, 31, 31, 12, 12, 31, 12 };
79 static const DECLARE_ALIGNED(16, float, zero64)[64];
81 #define SBR_INIT_VLC_STATIC(num, size) \
82 INIT_VLC_STATIC(&vlc_sbr[num], 9, sbr_tmp[num].table_size / sbr_tmp[num].elem_size, \
83 sbr_tmp[num].sbr_bits , 1, 1, \
84 sbr_tmp[num].sbr_codes, sbr_tmp[num].elem_size, sbr_tmp[num].elem_size, \
87 #define SBR_VLC_ROW(name) \
88 { name ## _codes, name ## _bits, sizeof(name ## _codes), sizeof(name ## _codes[0]) }
90 av_cold void ff_aac_sbr_init(void)
94 const void *sbr_codes, *sbr_bits;
95 const unsigned int table_size, elem_size;
97 SBR_VLC_ROW(t_huffman_env_1_5dB),
98 SBR_VLC_ROW(f_huffman_env_1_5dB),
99 SBR_VLC_ROW(t_huffman_env_bal_1_5dB),
100 SBR_VLC_ROW(f_huffman_env_bal_1_5dB),
101 SBR_VLC_ROW(t_huffman_env_3_0dB),
102 SBR_VLC_ROW(f_huffman_env_3_0dB),
103 SBR_VLC_ROW(t_huffman_env_bal_3_0dB),
104 SBR_VLC_ROW(f_huffman_env_bal_3_0dB),
105 SBR_VLC_ROW(t_huffman_noise_3_0dB),
106 SBR_VLC_ROW(t_huffman_noise_bal_3_0dB),
109 // SBR VLC table initialization
110 SBR_INIT_VLC_STATIC(0, 1098);
111 SBR_INIT_VLC_STATIC(1, 1092);
112 SBR_INIT_VLC_STATIC(2, 768);
113 SBR_INIT_VLC_STATIC(3, 1026);
114 SBR_INIT_VLC_STATIC(4, 1058);
115 SBR_INIT_VLC_STATIC(5, 1052);
116 SBR_INIT_VLC_STATIC(6, 544);
117 SBR_INIT_VLC_STATIC(7, 544);
118 SBR_INIT_VLC_STATIC(8, 592);
119 SBR_INIT_VLC_STATIC(9, 512);
121 for (n = 1; n < 320; n++)
122 sbr_qmf_window_us[320 + n] = sbr_qmf_window_us[320 - n];
123 sbr_qmf_window_us[384] = -sbr_qmf_window_us[384];
124 sbr_qmf_window_us[512] = -sbr_qmf_window_us[512];
126 for (n = 0; n < 320; n++)
127 sbr_qmf_window_ds[n] = sbr_qmf_window_us[2*n];
132 av_cold void ff_aac_sbr_ctx_init(AACContext *ac, SpectralBandReplication *sbr)
135 if(sbr->mdct.mdct_bits)
137 sbr->kx[0] = sbr->kx[1] = 32; //Typo in spec, kx' inits to 32
138 sbr->data[0].e_a[1] = sbr->data[1].e_a[1] = -1;
139 sbr->data[0].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
140 sbr->data[1].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
141 /* SBR requires samples to be scaled to +/-32768.0 to work correctly.
142 * mdct scale factors are adjusted to scale up from +/-1.0 at analysis
143 * and scale back down at synthesis. */
144 mdct_scale = ac->avctx->sample_fmt == AV_SAMPLE_FMT_FLT ? 32768.0f : 1.0f;
145 ff_mdct_init(&sbr->mdct, 7, 1, 1.0 / (64 * mdct_scale));
146 ff_mdct_init(&sbr->mdct_ana, 7, 1, -2.0 * mdct_scale);
147 ff_ps_ctx_init(&sbr->ps);
148 ff_sbrdsp_init(&sbr->dsp);
151 av_cold void ff_aac_sbr_ctx_close(SpectralBandReplication *sbr)
153 ff_mdct_end(&sbr->mdct);
154 ff_mdct_end(&sbr->mdct_ana);
157 static int qsort_comparison_function_int16(const void *a, const void *b)
159 return *(const int16_t *)a - *(const int16_t *)b;
162 static inline int in_table_int16(const int16_t *table, int last_el, int16_t needle)
165 for (i = 0; i <= last_el; i++)
166 if (table[i] == needle)
171 /// Limiter Frequency Band Table (14496-3 sp04 p198)
172 static void sbr_make_f_tablelim(SpectralBandReplication *sbr)
175 if (sbr->bs_limiter_bands > 0) {
176 static const float bands_warped[3] = { 1.32715174233856803909f, //2^(0.49/1.2)
177 1.18509277094158210129f, //2^(0.49/2)
178 1.11987160404675912501f }; //2^(0.49/3)
179 const float lim_bands_per_octave_warped = bands_warped[sbr->bs_limiter_bands - 1];
180 int16_t patch_borders[7];
181 uint16_t *in = sbr->f_tablelim + 1, *out = sbr->f_tablelim;
183 patch_borders[0] = sbr->kx[1];
184 for (k = 1; k <= sbr->num_patches; k++)
185 patch_borders[k] = patch_borders[k-1] + sbr->patch_num_subbands[k-1];
187 memcpy(sbr->f_tablelim, sbr->f_tablelow,
188 (sbr->n[0] + 1) * sizeof(sbr->f_tablelow[0]));
189 if (sbr->num_patches > 1)
190 memcpy(sbr->f_tablelim + sbr->n[0] + 1, patch_borders + 1,
191 (sbr->num_patches - 1) * sizeof(patch_borders[0]));
193 qsort(sbr->f_tablelim, sbr->num_patches + sbr->n[0],
194 sizeof(sbr->f_tablelim[0]),
195 qsort_comparison_function_int16);
197 sbr->n_lim = sbr->n[0] + sbr->num_patches - 1;
198 while (out < sbr->f_tablelim + sbr->n_lim) {
199 if (*in >= *out * lim_bands_per_octave_warped) {
201 } else if (*in == *out ||
202 !in_table_int16(patch_borders, sbr->num_patches, *in)) {
205 } else if (!in_table_int16(patch_borders, sbr->num_patches, *out)) {
213 sbr->f_tablelim[0] = sbr->f_tablelow[0];
214 sbr->f_tablelim[1] = sbr->f_tablelow[sbr->n[0]];
219 static unsigned int read_sbr_header(SpectralBandReplication *sbr, GetBitContext *gb)
221 unsigned int cnt = get_bits_count(gb);
222 uint8_t bs_header_extra_1;
223 uint8_t bs_header_extra_2;
224 int old_bs_limiter_bands = sbr->bs_limiter_bands;
225 SpectrumParameters old_spectrum_params;
229 // Save last spectrum parameters variables to compare to new ones
230 memcpy(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters));
232 sbr->bs_amp_res_header = get_bits1(gb);
233 sbr->spectrum_params.bs_start_freq = get_bits(gb, 4);
234 sbr->spectrum_params.bs_stop_freq = get_bits(gb, 4);
235 sbr->spectrum_params.bs_xover_band = get_bits(gb, 3);
236 skip_bits(gb, 2); // bs_reserved
238 bs_header_extra_1 = get_bits1(gb);
239 bs_header_extra_2 = get_bits1(gb);
241 if (bs_header_extra_1) {
242 sbr->spectrum_params.bs_freq_scale = get_bits(gb, 2);
243 sbr->spectrum_params.bs_alter_scale = get_bits1(gb);
244 sbr->spectrum_params.bs_noise_bands = get_bits(gb, 2);
246 sbr->spectrum_params.bs_freq_scale = 2;
247 sbr->spectrum_params.bs_alter_scale = 1;
248 sbr->spectrum_params.bs_noise_bands = 2;
251 // Check if spectrum parameters changed
252 if (memcmp(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters)))
255 if (bs_header_extra_2) {
256 sbr->bs_limiter_bands = get_bits(gb, 2);
257 sbr->bs_limiter_gains = get_bits(gb, 2);
258 sbr->bs_interpol_freq = get_bits1(gb);
259 sbr->bs_smoothing_mode = get_bits1(gb);
261 sbr->bs_limiter_bands = 2;
262 sbr->bs_limiter_gains = 2;
263 sbr->bs_interpol_freq = 1;
264 sbr->bs_smoothing_mode = 1;
267 if (sbr->bs_limiter_bands != old_bs_limiter_bands && !sbr->reset)
268 sbr_make_f_tablelim(sbr);
270 return get_bits_count(gb) - cnt;
273 static int array_min_int16(const int16_t *array, int nel)
275 int i, min = array[0];
276 for (i = 1; i < nel; i++)
277 min = FFMIN(array[i], min);
281 static void make_bands(int16_t* bands, int start, int stop, int num_bands)
283 int k, previous, present;
286 base = powf((float)stop / start, 1.0f / num_bands);
290 for (k = 0; k < num_bands-1; k++) {
292 present = lrintf(prod);
293 bands[k] = present - previous;
296 bands[num_bands-1] = stop - previous;
299 static int check_n_master(AVCodecContext *avctx, int n_master, int bs_xover_band)
301 // Requirements (14496-3 sp04 p205)
303 av_log(avctx, AV_LOG_ERROR, "Invalid n_master: %d\n", n_master);
306 if (bs_xover_band >= n_master) {
307 av_log(avctx, AV_LOG_ERROR,
308 "Invalid bitstream, crossover band index beyond array bounds: %d\n",
315 /// Master Frequency Band Table (14496-3 sp04 p194)
316 static int sbr_make_f_master(AACContext *ac, SpectralBandReplication *sbr,
317 SpectrumParameters *spectrum)
319 unsigned int temp, max_qmf_subbands;
320 unsigned int start_min, stop_min;
322 const int8_t *sbr_offset_ptr;
325 if (sbr->sample_rate < 32000) {
327 } else if (sbr->sample_rate < 64000) {
332 start_min = ((temp << 7) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
333 stop_min = ((temp << 8) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
335 switch (sbr->sample_rate) {
337 sbr_offset_ptr = sbr_offset[0];
340 sbr_offset_ptr = sbr_offset[1];
343 sbr_offset_ptr = sbr_offset[2];
346 sbr_offset_ptr = sbr_offset[3];
348 case 44100: case 48000: case 64000:
349 sbr_offset_ptr = sbr_offset[4];
351 case 88200: case 96000: case 128000: case 176400: case 192000:
352 sbr_offset_ptr = sbr_offset[5];
355 av_log(ac->avctx, AV_LOG_ERROR,
356 "Unsupported sample rate for SBR: %d\n", sbr->sample_rate);
360 sbr->k[0] = start_min + sbr_offset_ptr[spectrum->bs_start_freq];
362 if (spectrum->bs_stop_freq < 14) {
363 sbr->k[2] = stop_min;
364 make_bands(stop_dk, stop_min, 64, 13);
365 qsort(stop_dk, 13, sizeof(stop_dk[0]), qsort_comparison_function_int16);
366 for (k = 0; k < spectrum->bs_stop_freq; k++)
367 sbr->k[2] += stop_dk[k];
368 } else if (spectrum->bs_stop_freq == 14) {
369 sbr->k[2] = 2*sbr->k[0];
370 } else if (spectrum->bs_stop_freq == 15) {
371 sbr->k[2] = 3*sbr->k[0];
373 av_log(ac->avctx, AV_LOG_ERROR,
374 "Invalid bs_stop_freq: %d\n", spectrum->bs_stop_freq);
377 sbr->k[2] = FFMIN(64, sbr->k[2]);
379 // Requirements (14496-3 sp04 p205)
380 if (sbr->sample_rate <= 32000) {
381 max_qmf_subbands = 48;
382 } else if (sbr->sample_rate == 44100) {
383 max_qmf_subbands = 35;
384 } else if (sbr->sample_rate >= 48000)
385 max_qmf_subbands = 32;
387 if (sbr->k[2] - sbr->k[0] > max_qmf_subbands) {
388 av_log(ac->avctx, AV_LOG_ERROR,
389 "Invalid bitstream, too many QMF subbands: %d\n", sbr->k[2] - sbr->k[0]);
393 if (!spectrum->bs_freq_scale) {
396 dk = spectrum->bs_alter_scale + 1;
397 sbr->n_master = ((sbr->k[2] - sbr->k[0] + (dk&2)) >> dk) << 1;
398 if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
401 for (k = 1; k <= sbr->n_master; k++)
402 sbr->f_master[k] = dk;
404 k2diff = sbr->k[2] - sbr->k[0] - sbr->n_master * dk;
407 sbr->f_master[2]-= (k2diff < -1);
409 sbr->f_master[sbr->n_master]++;
412 sbr->f_master[0] = sbr->k[0];
413 for (k = 1; k <= sbr->n_master; k++)
414 sbr->f_master[k] += sbr->f_master[k - 1];
417 int half_bands = 7 - spectrum->bs_freq_scale; // bs_freq_scale = {1,2,3}
418 int two_regions, num_bands_0;
419 int vdk0_max, vdk1_min;
422 if (49 * sbr->k[2] > 110 * sbr->k[0]) {
424 sbr->k[1] = 2 * sbr->k[0];
427 sbr->k[1] = sbr->k[2];
430 num_bands_0 = lrintf(half_bands * log2f(sbr->k[1] / (float)sbr->k[0])) * 2;
432 if (num_bands_0 <= 0) { // Requirements (14496-3 sp04 p205)
433 av_log(ac->avctx, AV_LOG_ERROR, "Invalid num_bands_0: %d\n", num_bands_0);
439 make_bands(vk0+1, sbr->k[0], sbr->k[1], num_bands_0);
441 qsort(vk0 + 1, num_bands_0, sizeof(vk0[1]), qsort_comparison_function_int16);
442 vdk0_max = vk0[num_bands_0];
445 for (k = 1; k <= num_bands_0; k++) {
446 if (vk0[k] <= 0) { // Requirements (14496-3 sp04 p205)
447 av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk0[%d]: %d\n", k, vk0[k]);
455 float invwarp = spectrum->bs_alter_scale ? 0.76923076923076923077f
456 : 1.0f; // bs_alter_scale = {0,1}
457 int num_bands_1 = lrintf(half_bands * invwarp *
458 log2f(sbr->k[2] / (float)sbr->k[1])) * 2;
460 make_bands(vk1+1, sbr->k[1], sbr->k[2], num_bands_1);
462 vdk1_min = array_min_int16(vk1 + 1, num_bands_1);
464 if (vdk1_min < vdk0_max) {
466 qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
467 change = FFMIN(vdk0_max - vk1[1], (vk1[num_bands_1] - vk1[1]) >> 1);
469 vk1[num_bands_1] -= change;
472 qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
475 for (k = 1; k <= num_bands_1; k++) {
476 if (vk1[k] <= 0) { // Requirements (14496-3 sp04 p205)
477 av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk1[%d]: %d\n", k, vk1[k]);
483 sbr->n_master = num_bands_0 + num_bands_1;
484 if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
486 memcpy(&sbr->f_master[0], vk0,
487 (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
488 memcpy(&sbr->f_master[num_bands_0 + 1], vk1 + 1,
489 num_bands_1 * sizeof(sbr->f_master[0]));
492 sbr->n_master = num_bands_0;
493 if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
495 memcpy(sbr->f_master, vk0, (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
502 /// High Frequency Generation - Patch Construction (14496-3 sp04 p216 fig. 4.46)
503 static int sbr_hf_calc_npatches(AACContext *ac, SpectralBandReplication *sbr)
507 int usb = sbr->kx[1];
508 int goal_sb = ((1000 << 11) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
510 sbr->num_patches = 0;
512 if (goal_sb < sbr->kx[1] + sbr->m[1]) {
513 for (k = 0; sbr->f_master[k] < goal_sb; k++) ;
519 for (i = k; i == k || sb > (sbr->k[0] - 1 + msb - odd); i--) {
520 sb = sbr->f_master[i];
521 odd = (sb + sbr->k[0]) & 1;
524 // Requirements (14496-3 sp04 p205) sets the maximum number of patches to 5.
525 // After this check the final number of patches can still be six which is
526 // illegal however the Coding Technologies decoder check stream has a final
527 // count of 6 patches
528 if (sbr->num_patches > 5) {
529 av_log(ac->avctx, AV_LOG_ERROR, "Too many patches: %d\n", sbr->num_patches);
533 sbr->patch_num_subbands[sbr->num_patches] = FFMAX(sb - usb, 0);
534 sbr->patch_start_subband[sbr->num_patches] = sbr->k[0] - odd - sbr->patch_num_subbands[sbr->num_patches];
536 if (sbr->patch_num_subbands[sbr->num_patches] > 0) {
543 if (sbr->f_master[k] - sb < 3)
545 } while (sb != sbr->kx[1] + sbr->m[1]);
547 if (sbr->patch_num_subbands[sbr->num_patches-1] < 3 && sbr->num_patches > 1)
553 /// Derived Frequency Band Tables (14496-3 sp04 p197)
554 static int sbr_make_f_derived(AACContext *ac, SpectralBandReplication *sbr)
558 sbr->n[1] = sbr->n_master - sbr->spectrum_params.bs_xover_band;
559 sbr->n[0] = (sbr->n[1] + 1) >> 1;
561 memcpy(sbr->f_tablehigh, &sbr->f_master[sbr->spectrum_params.bs_xover_band],
562 (sbr->n[1] + 1) * sizeof(sbr->f_master[0]));
563 sbr->m[1] = sbr->f_tablehigh[sbr->n[1]] - sbr->f_tablehigh[0];
564 sbr->kx[1] = sbr->f_tablehigh[0];
566 // Requirements (14496-3 sp04 p205)
567 if (sbr->kx[1] + sbr->m[1] > 64) {
568 av_log(ac->avctx, AV_LOG_ERROR,
569 "Stop frequency border too high: %d\n", sbr->kx[1] + sbr->m[1]);
572 if (sbr->kx[1] > 32) {
573 av_log(ac->avctx, AV_LOG_ERROR, "Start frequency border too high: %d\n", sbr->kx[1]);
577 sbr->f_tablelow[0] = sbr->f_tablehigh[0];
578 temp = sbr->n[1] & 1;
579 for (k = 1; k <= sbr->n[0]; k++)
580 sbr->f_tablelow[k] = sbr->f_tablehigh[2 * k - temp];
582 sbr->n_q = FFMAX(1, lrintf(sbr->spectrum_params.bs_noise_bands *
583 log2f(sbr->k[2] / (float)sbr->kx[1]))); // 0 <= bs_noise_bands <= 3
585 av_log(ac->avctx, AV_LOG_ERROR, "Too many noise floor scale factors: %d\n", sbr->n_q);
589 sbr->f_tablenoise[0] = sbr->f_tablelow[0];
591 for (k = 1; k <= sbr->n_q; k++) {
592 temp += (sbr->n[0] - temp) / (sbr->n_q + 1 - k);
593 sbr->f_tablenoise[k] = sbr->f_tablelow[temp];
596 if (sbr_hf_calc_npatches(ac, sbr) < 0)
599 sbr_make_f_tablelim(sbr);
601 sbr->data[0].f_indexnoise = 0;
602 sbr->data[1].f_indexnoise = 0;
607 static av_always_inline void get_bits1_vector(GetBitContext *gb, uint8_t *vec,
611 for (i = 0; i < elements; i++) {
612 vec[i] = get_bits1(gb);
616 /** ceil(log2(index+1)) */
617 static const int8_t ceil_log2[] = {
621 static int read_sbr_grid(AACContext *ac, SpectralBandReplication *sbr,
622 GetBitContext *gb, SBRData *ch_data)
625 unsigned bs_pointer = 0;
626 // frameLengthFlag ? 15 : 16; 960 sample length frames unsupported; this value is numTimeSlots
627 int abs_bord_trail = 16;
628 int num_rel_lead, num_rel_trail;
629 unsigned bs_num_env_old = ch_data->bs_num_env;
631 ch_data->bs_freq_res[0] = ch_data->bs_freq_res[ch_data->bs_num_env];
632 ch_data->bs_amp_res = sbr->bs_amp_res_header;
633 ch_data->t_env_num_env_old = ch_data->t_env[bs_num_env_old];
635 switch (ch_data->bs_frame_class = get_bits(gb, 2)) {
637 ch_data->bs_num_env = 1 << get_bits(gb, 2);
638 num_rel_lead = ch_data->bs_num_env - 1;
639 if (ch_data->bs_num_env == 1)
640 ch_data->bs_amp_res = 0;
642 if (ch_data->bs_num_env > 4) {
643 av_log(ac->avctx, AV_LOG_ERROR,
644 "Invalid bitstream, too many SBR envelopes in FIXFIX type SBR frame: %d\n",
645 ch_data->bs_num_env);
649 ch_data->t_env[0] = 0;
650 ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
652 abs_bord_trail = (abs_bord_trail + (ch_data->bs_num_env >> 1)) /
654 for (i = 0; i < num_rel_lead; i++)
655 ch_data->t_env[i + 1] = ch_data->t_env[i] + abs_bord_trail;
657 ch_data->bs_freq_res[1] = get_bits1(gb);
658 for (i = 1; i < ch_data->bs_num_env; i++)
659 ch_data->bs_freq_res[i + 1] = ch_data->bs_freq_res[1];
662 abs_bord_trail += get_bits(gb, 2);
663 num_rel_trail = get_bits(gb, 2);
664 ch_data->bs_num_env = num_rel_trail + 1;
665 ch_data->t_env[0] = 0;
666 ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
668 for (i = 0; i < num_rel_trail; i++)
669 ch_data->t_env[ch_data->bs_num_env - 1 - i] =
670 ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
672 bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
674 for (i = 0; i < ch_data->bs_num_env; i++)
675 ch_data->bs_freq_res[ch_data->bs_num_env - i] = get_bits1(gb);
678 ch_data->t_env[0] = get_bits(gb, 2);
679 num_rel_lead = get_bits(gb, 2);
680 ch_data->bs_num_env = num_rel_lead + 1;
681 ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
683 for (i = 0; i < num_rel_lead; i++)
684 ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
686 bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
688 get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
691 ch_data->t_env[0] = get_bits(gb, 2);
692 abs_bord_trail += get_bits(gb, 2);
693 num_rel_lead = get_bits(gb, 2);
694 num_rel_trail = get_bits(gb, 2);
695 ch_data->bs_num_env = num_rel_lead + num_rel_trail + 1;
697 if (ch_data->bs_num_env > 5) {
698 av_log(ac->avctx, AV_LOG_ERROR,
699 "Invalid bitstream, too many SBR envelopes in VARVAR type SBR frame: %d\n",
700 ch_data->bs_num_env);
704 ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
706 for (i = 0; i < num_rel_lead; i++)
707 ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
708 for (i = 0; i < num_rel_trail; i++)
709 ch_data->t_env[ch_data->bs_num_env - 1 - i] =
710 ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
712 bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
714 get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
718 if (bs_pointer > ch_data->bs_num_env + 1) {
719 av_log(ac->avctx, AV_LOG_ERROR,
720 "Invalid bitstream, bs_pointer points to a middle noise border outside the time borders table: %d\n",
725 for (i = 1; i <= ch_data->bs_num_env; i++) {
726 if (ch_data->t_env[i-1] > ch_data->t_env[i]) {
727 av_log(ac->avctx, AV_LOG_ERROR, "Non monotone time borders\n");
732 ch_data->bs_num_noise = (ch_data->bs_num_env > 1) + 1;
734 ch_data->t_q[0] = ch_data->t_env[0];
735 ch_data->t_q[ch_data->bs_num_noise] = ch_data->t_env[ch_data->bs_num_env];
736 if (ch_data->bs_num_noise > 1) {
738 if (ch_data->bs_frame_class == FIXFIX) {
739 idx = ch_data->bs_num_env >> 1;
740 } else if (ch_data->bs_frame_class & 1) { // FIXVAR or VARVAR
741 idx = ch_data->bs_num_env - FFMAX(bs_pointer - 1, 1);
745 else if (bs_pointer == 1)
746 idx = ch_data->bs_num_env - 1;
747 else // bs_pointer > 1
748 idx = bs_pointer - 1;
750 ch_data->t_q[1] = ch_data->t_env[idx];
753 ch_data->e_a[0] = -(ch_data->e_a[1] != bs_num_env_old); // l_APrev
754 ch_data->e_a[1] = -1;
755 if ((ch_data->bs_frame_class & 1) && bs_pointer) { // FIXVAR or VARVAR and bs_pointer != 0
756 ch_data->e_a[1] = ch_data->bs_num_env + 1 - bs_pointer;
757 } else if ((ch_data->bs_frame_class == 2) && (bs_pointer > 1)) // VARFIX and bs_pointer > 1
758 ch_data->e_a[1] = bs_pointer - 1;
763 static void copy_sbr_grid(SBRData *dst, const SBRData *src) {
764 //These variables are saved from the previous frame rather than copied
765 dst->bs_freq_res[0] = dst->bs_freq_res[dst->bs_num_env];
766 dst->t_env_num_env_old = dst->t_env[dst->bs_num_env];
767 dst->e_a[0] = -(dst->e_a[1] != dst->bs_num_env);
769 //These variables are read from the bitstream and therefore copied
770 memcpy(dst->bs_freq_res+1, src->bs_freq_res+1, sizeof(dst->bs_freq_res)-sizeof(*dst->bs_freq_res));
771 memcpy(dst->t_env, src->t_env, sizeof(dst->t_env));
772 memcpy(dst->t_q, src->t_q, sizeof(dst->t_q));
773 dst->bs_num_env = src->bs_num_env;
774 dst->bs_amp_res = src->bs_amp_res;
775 dst->bs_num_noise = src->bs_num_noise;
776 dst->bs_frame_class = src->bs_frame_class;
777 dst->e_a[1] = src->e_a[1];
780 /// Read how the envelope and noise floor data is delta coded
781 static void read_sbr_dtdf(SpectralBandReplication *sbr, GetBitContext *gb,
784 get_bits1_vector(gb, ch_data->bs_df_env, ch_data->bs_num_env);
785 get_bits1_vector(gb, ch_data->bs_df_noise, ch_data->bs_num_noise);
788 /// Read inverse filtering data
789 static void read_sbr_invf(SpectralBandReplication *sbr, GetBitContext *gb,
794 memcpy(ch_data->bs_invf_mode[1], ch_data->bs_invf_mode[0], 5 * sizeof(uint8_t));
795 for (i = 0; i < sbr->n_q; i++)
796 ch_data->bs_invf_mode[0][i] = get_bits(gb, 2);
799 static void read_sbr_envelope(SpectralBandReplication *sbr, GetBitContext *gb,
800 SBRData *ch_data, int ch)
804 VLC_TYPE (*t_huff)[2], (*f_huff)[2];
806 const int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
807 const int odd = sbr->n[1] & 1;
809 if (sbr->bs_coupling && ch) {
810 if (ch_data->bs_amp_res) {
812 t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_3_0DB].table;
813 t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_3_0DB];
814 f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
815 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
818 t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_1_5DB].table;
819 t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_1_5DB];
820 f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_1_5DB].table;
821 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_1_5DB];
824 if (ch_data->bs_amp_res) {
826 t_huff = vlc_sbr[T_HUFFMAN_ENV_3_0DB].table;
827 t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_3_0DB];
828 f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
829 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
832 t_huff = vlc_sbr[T_HUFFMAN_ENV_1_5DB].table;
833 t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_1_5DB];
834 f_huff = vlc_sbr[F_HUFFMAN_ENV_1_5DB].table;
835 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_1_5DB];
839 for (i = 0; i < ch_data->bs_num_env; i++) {
840 if (ch_data->bs_df_env[i]) {
841 // bs_freq_res[0] == bs_freq_res[bs_num_env] from prev frame
842 if (ch_data->bs_freq_res[i + 1] == ch_data->bs_freq_res[i]) {
843 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
844 ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
845 } else if (ch_data->bs_freq_res[i + 1]) {
846 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
847 k = (j + odd) >> 1; // find k such that f_tablelow[k] <= f_tablehigh[j] < f_tablelow[k + 1]
848 ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
851 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
852 k = j ? 2*j - odd : 0; // find k such that f_tablehigh[k] == f_tablelow[j]
853 ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
857 ch_data->env_facs[i + 1][0] = delta * get_bits(gb, bits); // bs_env_start_value_balance
858 for (j = 1; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
859 ch_data->env_facs[i + 1][j] = ch_data->env_facs[i + 1][j - 1] + delta * (get_vlc2(gb, f_huff, 9, 3) - f_lav);
863 //assign 0th elements of env_facs from last elements
864 memcpy(ch_data->env_facs[0], ch_data->env_facs[ch_data->bs_num_env],
865 sizeof(ch_data->env_facs[0]));
868 static void read_sbr_noise(SpectralBandReplication *sbr, GetBitContext *gb,
869 SBRData *ch_data, int ch)
872 VLC_TYPE (*t_huff)[2], (*f_huff)[2];
874 int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
876 if (sbr->bs_coupling && ch) {
877 t_huff = vlc_sbr[T_HUFFMAN_NOISE_BAL_3_0DB].table;
878 t_lav = vlc_sbr_lav[T_HUFFMAN_NOISE_BAL_3_0DB];
879 f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
880 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
882 t_huff = vlc_sbr[T_HUFFMAN_NOISE_3_0DB].table;
883 t_lav = vlc_sbr_lav[T_HUFFMAN_NOISE_3_0DB];
884 f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
885 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
888 for (i = 0; i < ch_data->bs_num_noise; i++) {
889 if (ch_data->bs_df_noise[i]) {
890 for (j = 0; j < sbr->n_q; j++)
891 ch_data->noise_facs[i + 1][j] = ch_data->noise_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 2) - t_lav);
893 ch_data->noise_facs[i + 1][0] = delta * get_bits(gb, 5); // bs_noise_start_value_balance or bs_noise_start_value_level
894 for (j = 1; j < sbr->n_q; j++)
895 ch_data->noise_facs[i + 1][j] = ch_data->noise_facs[i + 1][j - 1] + delta * (get_vlc2(gb, f_huff, 9, 3) - f_lav);
899 //assign 0th elements of noise_facs from last elements
900 memcpy(ch_data->noise_facs[0], ch_data->noise_facs[ch_data->bs_num_noise],
901 sizeof(ch_data->noise_facs[0]));
904 static void read_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
906 int bs_extension_id, int *num_bits_left)
908 switch (bs_extension_id) {
909 case EXTENSION_ID_PS:
911 av_log(ac->avctx, AV_LOG_ERROR, "Parametric Stereo signaled to be not-present but was found in the bitstream.\n");
912 skip_bits_long(gb, *num_bits_left); // bs_fill_bits
916 *num_bits_left -= ff_ps_read_data(ac->avctx, gb, &sbr->ps, *num_bits_left);
918 av_log_missing_feature(ac->avctx, "Parametric Stereo is", 0);
919 skip_bits_long(gb, *num_bits_left); // bs_fill_bits
925 av_log_missing_feature(ac->avctx, "Reserved SBR extensions are", 1);
926 skip_bits_long(gb, *num_bits_left); // bs_fill_bits
932 static int read_sbr_single_channel_element(AACContext *ac,
933 SpectralBandReplication *sbr,
936 if (get_bits1(gb)) // bs_data_extra
937 skip_bits(gb, 4); // bs_reserved
939 if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
941 read_sbr_dtdf(sbr, gb, &sbr->data[0]);
942 read_sbr_invf(sbr, gb, &sbr->data[0]);
943 read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
944 read_sbr_noise(sbr, gb, &sbr->data[0], 0);
946 if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
947 get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
952 static int read_sbr_channel_pair_element(AACContext *ac,
953 SpectralBandReplication *sbr,
956 if (get_bits1(gb)) // bs_data_extra
957 skip_bits(gb, 8); // bs_reserved
959 if ((sbr->bs_coupling = get_bits1(gb))) {
960 if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
962 copy_sbr_grid(&sbr->data[1], &sbr->data[0]);
963 read_sbr_dtdf(sbr, gb, &sbr->data[0]);
964 read_sbr_dtdf(sbr, gb, &sbr->data[1]);
965 read_sbr_invf(sbr, gb, &sbr->data[0]);
966 memcpy(sbr->data[1].bs_invf_mode[1], sbr->data[1].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
967 memcpy(sbr->data[1].bs_invf_mode[0], sbr->data[0].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
968 read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
969 read_sbr_noise(sbr, gb, &sbr->data[0], 0);
970 read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
971 read_sbr_noise(sbr, gb, &sbr->data[1], 1);
973 if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]) ||
974 read_sbr_grid(ac, sbr, gb, &sbr->data[1]))
976 read_sbr_dtdf(sbr, gb, &sbr->data[0]);
977 read_sbr_dtdf(sbr, gb, &sbr->data[1]);
978 read_sbr_invf(sbr, gb, &sbr->data[0]);
979 read_sbr_invf(sbr, gb, &sbr->data[1]);
980 read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
981 read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
982 read_sbr_noise(sbr, gb, &sbr->data[0], 0);
983 read_sbr_noise(sbr, gb, &sbr->data[1], 1);
986 if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
987 get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
988 if ((sbr->data[1].bs_add_harmonic_flag = get_bits1(gb)))
989 get_bits1_vector(gb, sbr->data[1].bs_add_harmonic, sbr->n[1]);
994 static unsigned int read_sbr_data(AACContext *ac, SpectralBandReplication *sbr,
995 GetBitContext *gb, int id_aac)
997 unsigned int cnt = get_bits_count(gb);
999 if (id_aac == TYPE_SCE || id_aac == TYPE_CCE) {
1000 if (read_sbr_single_channel_element(ac, sbr, gb)) {
1002 return get_bits_count(gb) - cnt;
1004 } else if (id_aac == TYPE_CPE) {
1005 if (read_sbr_channel_pair_element(ac, sbr, gb)) {
1007 return get_bits_count(gb) - cnt;
1010 av_log(ac->avctx, AV_LOG_ERROR,
1011 "Invalid bitstream - cannot apply SBR to element type %d\n", id_aac);
1013 return get_bits_count(gb) - cnt;
1015 if (get_bits1(gb)) { // bs_extended_data
1016 int num_bits_left = get_bits(gb, 4); // bs_extension_size
1017 if (num_bits_left == 15)
1018 num_bits_left += get_bits(gb, 8); // bs_esc_count
1020 num_bits_left <<= 3;
1021 while (num_bits_left > 7) {
1023 read_sbr_extension(ac, sbr, gb, get_bits(gb, 2), &num_bits_left); // bs_extension_id
1025 if (num_bits_left < 0) {
1026 av_log(ac->avctx, AV_LOG_ERROR, "SBR Extension over read.\n");
1028 if (num_bits_left > 0)
1029 skip_bits(gb, num_bits_left);
1032 return get_bits_count(gb) - cnt;
1035 static void sbr_reset(AACContext *ac, SpectralBandReplication *sbr)
1038 err = sbr_make_f_master(ac, sbr, &sbr->spectrum_params);
1040 err = sbr_make_f_derived(ac, sbr);
1042 av_log(ac->avctx, AV_LOG_ERROR,
1043 "SBR reset failed. Switching SBR to pure upsampling mode.\n");
1049 * Decode Spectral Band Replication extension data; reference: table 4.55.
1051 * @param crc flag indicating the presence of CRC checksum
1052 * @param cnt length of TYPE_FIL syntactic element in bytes
1054 * @return Returns number of bytes consumed from the TYPE_FIL element.
1056 int ff_decode_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
1057 GetBitContext *gb_host, int crc, int cnt, int id_aac)
1059 unsigned int num_sbr_bits = 0, num_align_bits;
1060 unsigned bytes_read;
1061 GetBitContext gbc = *gb_host, *gb = &gbc;
1062 skip_bits_long(gb_host, cnt*8 - 4);
1066 if (!sbr->sample_rate)
1067 sbr->sample_rate = 2 * ac->m4ac.sample_rate; //TODO use the nominal sample rate for arbitrary sample rate support
1068 if (!ac->m4ac.ext_sample_rate)
1069 ac->m4ac.ext_sample_rate = 2 * ac->m4ac.sample_rate;
1072 skip_bits(gb, 10); // bs_sbr_crc_bits; TODO - implement CRC check
1076 //Save some state from the previous frame.
1077 sbr->kx[0] = sbr->kx[1];
1078 sbr->m[0] = sbr->m[1];
1081 if (get_bits1(gb)) // bs_header_flag
1082 num_sbr_bits += read_sbr_header(sbr, gb);
1088 num_sbr_bits += read_sbr_data(ac, sbr, gb, id_aac);
1090 num_align_bits = ((cnt << 3) - 4 - num_sbr_bits) & 7;
1091 bytes_read = ((num_sbr_bits + num_align_bits + 4) >> 3);
1093 if (bytes_read > cnt) {
1094 av_log(ac->avctx, AV_LOG_ERROR,
1095 "Expected to read %d SBR bytes actually read %d.\n", cnt, bytes_read);
1100 /// Dequantization and stereo decoding (14496-3 sp04 p203)
1101 static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
1106 if (id_aac == TYPE_CPE && sbr->bs_coupling) {
1107 float alpha = sbr->data[0].bs_amp_res ? 1.0f : 0.5f;
1108 float pan_offset = sbr->data[0].bs_amp_res ? 12.0f : 24.0f;
1109 for (e = 1; e <= sbr->data[0].bs_num_env; e++) {
1110 for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) {
1111 float temp1 = exp2f(sbr->data[0].env_facs[e][k] * alpha + 7.0f);
1112 float temp2 = exp2f((pan_offset - sbr->data[1].env_facs[e][k]) * alpha);
1113 float fac = temp1 / (1.0f + temp2);
1114 sbr->data[0].env_facs[e][k] = fac;
1115 sbr->data[1].env_facs[e][k] = fac * temp2;
1118 for (e = 1; e <= sbr->data[0].bs_num_noise; e++) {
1119 for (k = 0; k < sbr->n_q; k++) {
1120 float temp1 = exp2f(NOISE_FLOOR_OFFSET - sbr->data[0].noise_facs[e][k] + 1);
1121 float temp2 = exp2f(12 - sbr->data[1].noise_facs[e][k]);
1122 float fac = temp1 / (1.0f + temp2);
1123 sbr->data[0].noise_facs[e][k] = fac;
1124 sbr->data[1].noise_facs[e][k] = fac * temp2;
1127 } else { // SCE or one non-coupled CPE
1128 for (ch = 0; ch < (id_aac == TYPE_CPE) + 1; ch++) {
1129 float alpha = sbr->data[ch].bs_amp_res ? 1.0f : 0.5f;
1130 for (e = 1; e <= sbr->data[ch].bs_num_env; e++)
1131 for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++)
1132 sbr->data[ch].env_facs[e][k] =
1133 exp2f(alpha * sbr->data[ch].env_facs[e][k] + 6.0f);
1134 for (e = 1; e <= sbr->data[ch].bs_num_noise; e++)
1135 for (k = 0; k < sbr->n_q; k++)
1136 sbr->data[ch].noise_facs[e][k] =
1137 exp2f(NOISE_FLOOR_OFFSET - sbr->data[ch].noise_facs[e][k]);
1143 * Analysis QMF Bank (14496-3 sp04 p206)
1145 * @param x pointer to the beginning of the first sample window
1146 * @param W array of complex-valued samples split into subbands
1148 static void sbr_qmf_analysis(DSPContext *dsp, FFTContext *mdct,
1149 SBRDSPContext *sbrdsp, const float *in, float *x,
1150 float z[320], float W[2][32][32][2])
1153 memcpy(W[0], W[1], sizeof(W[0]));
1154 memcpy(x , x+1024, (320-32)*sizeof(x[0]));
1155 memcpy(x+288, in, 1024*sizeof(x[0]));
1156 for (i = 0; i < 32; i++) { // numTimeSlots*RATE = 16*2 as 960 sample frames
1157 // are not supported
1158 dsp->vector_fmul_reverse(z, sbr_qmf_window_ds, x, 320);
1160 sbrdsp->qmf_pre_shuffle(z);
1161 mdct->imdct_half(mdct, z, z+64);
1162 sbrdsp->qmf_post_shuffle(W[1][i], z);
1168 * Synthesis QMF Bank (14496-3 sp04 p206) and Downsampled Synthesis QMF Bank
1169 * (14496-3 sp04 p206)
1171 static void sbr_qmf_synthesis(DSPContext *dsp, FFTContext *mdct,
1172 SBRDSPContext *sbrdsp,
1173 float *out, float X[2][38][64],
1174 float mdct_buf[2][64],
1175 float *v0, int *v_off, const unsigned int div)
1178 const float *sbr_qmf_window = div ? sbr_qmf_window_ds : sbr_qmf_window_us;
1179 const int step = 128 >> div;
1181 for (i = 0; i < 32; i++) {
1182 if (*v_off < step) {
1183 int saved_samples = (1280 - 128) >> div;
1184 memcpy(&v0[SBR_SYNTHESIS_BUF_SIZE - saved_samples], v0, saved_samples * sizeof(float));
1185 *v_off = SBR_SYNTHESIS_BUF_SIZE - saved_samples - step;
1191 for (n = 0; n < 32; n++) {
1192 X[0][i][ n] = -X[0][i][n];
1193 X[0][i][32+n] = X[1][i][31-n];
1195 mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1196 sbrdsp->qmf_deint_neg(v, mdct_buf[0]);
1198 sbrdsp->neg_odd_64(X[1][i]);
1199 mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1200 mdct->imdct_half(mdct, mdct_buf[1], X[1][i]);
1201 sbrdsp->qmf_deint_bfly(v, mdct_buf[1], mdct_buf[0]);
1203 dsp->vector_fmul_add(out, v , sbr_qmf_window , zero64, 64 >> div);
1204 dsp->vector_fmul_add(out, v + ( 192 >> div), sbr_qmf_window + ( 64 >> div), out , 64 >> div);
1205 dsp->vector_fmul_add(out, v + ( 256 >> div), sbr_qmf_window + (128 >> div), out , 64 >> div);
1206 dsp->vector_fmul_add(out, v + ( 448 >> div), sbr_qmf_window + (192 >> div), out , 64 >> div);
1207 dsp->vector_fmul_add(out, v + ( 512 >> div), sbr_qmf_window + (256 >> div), out , 64 >> div);
1208 dsp->vector_fmul_add(out, v + ( 704 >> div), sbr_qmf_window + (320 >> div), out , 64 >> div);
1209 dsp->vector_fmul_add(out, v + ( 768 >> div), sbr_qmf_window + (384 >> div), out , 64 >> div);
1210 dsp->vector_fmul_add(out, v + ( 960 >> div), sbr_qmf_window + (448 >> div), out , 64 >> div);
1211 dsp->vector_fmul_add(out, v + (1024 >> div), sbr_qmf_window + (512 >> div), out , 64 >> div);
1212 dsp->vector_fmul_add(out, v + (1216 >> div), sbr_qmf_window + (576 >> div), out , 64 >> div);
1217 /** High Frequency Generation (14496-3 sp04 p214+) and Inverse Filtering
1218 * (14496-3 sp04 p214)
1219 * Warning: This routine does not seem numerically stable.
1221 static void sbr_hf_inverse_filter(SBRDSPContext *dsp,
1222 float (*alpha0)[2], float (*alpha1)[2],
1223 const float X_low[32][40][2], int k0)
1226 for (k = 0; k < k0; k++) {
1227 LOCAL_ALIGNED_16(float, phi, [3], [2][2]);
1230 dsp->autocorrelate(X_low[k], phi);
1232 dk = phi[2][1][0] * phi[1][0][0] -
1233 (phi[1][1][0] * phi[1][1][0] + phi[1][1][1] * phi[1][1][1]) / 1.000001f;
1239 float temp_real, temp_im;
1240 temp_real = phi[0][0][0] * phi[1][1][0] -
1241 phi[0][0][1] * phi[1][1][1] -
1242 phi[0][1][0] * phi[1][0][0];
1243 temp_im = phi[0][0][0] * phi[1][1][1] +
1244 phi[0][0][1] * phi[1][1][0] -
1245 phi[0][1][1] * phi[1][0][0];
1247 alpha1[k][0] = temp_real / dk;
1248 alpha1[k][1] = temp_im / dk;
1251 if (!phi[1][0][0]) {
1255 float temp_real, temp_im;
1256 temp_real = phi[0][0][0] + alpha1[k][0] * phi[1][1][0] +
1257 alpha1[k][1] * phi[1][1][1];
1258 temp_im = phi[0][0][1] + alpha1[k][1] * phi[1][1][0] -
1259 alpha1[k][0] * phi[1][1][1];
1261 alpha0[k][0] = -temp_real / phi[1][0][0];
1262 alpha0[k][1] = -temp_im / phi[1][0][0];
1265 if (alpha1[k][0] * alpha1[k][0] + alpha1[k][1] * alpha1[k][1] >= 16.0f ||
1266 alpha0[k][0] * alpha0[k][0] + alpha0[k][1] * alpha0[k][1] >= 16.0f) {
1275 /// Chirp Factors (14496-3 sp04 p214)
1276 static void sbr_chirp(SpectralBandReplication *sbr, SBRData *ch_data)
1280 static const float bw_tab[] = { 0.0f, 0.75f, 0.9f, 0.98f };
1282 for (i = 0; i < sbr->n_q; i++) {
1283 if (ch_data->bs_invf_mode[0][i] + ch_data->bs_invf_mode[1][i] == 1) {
1286 new_bw = bw_tab[ch_data->bs_invf_mode[0][i]];
1288 if (new_bw < ch_data->bw_array[i]) {
1289 new_bw = 0.75f * new_bw + 0.25f * ch_data->bw_array[i];
1291 new_bw = 0.90625f * new_bw + 0.09375f * ch_data->bw_array[i];
1292 ch_data->bw_array[i] = new_bw < 0.015625f ? 0.0f : new_bw;
1296 /// Generate the subband filtered lowband
1297 static int sbr_lf_gen(AACContext *ac, SpectralBandReplication *sbr,
1298 float X_low[32][40][2], const float W[2][32][32][2])
1301 const int t_HFGen = 8;
1303 memset(X_low, 0, 32*sizeof(*X_low));
1304 for (k = 0; k < sbr->kx[1]; k++) {
1305 for (i = t_HFGen; i < i_f + t_HFGen; i++) {
1306 X_low[k][i][0] = W[1][i - t_HFGen][k][0];
1307 X_low[k][i][1] = W[1][i - t_HFGen][k][1];
1310 for (k = 0; k < sbr->kx[0]; k++) {
1311 for (i = 0; i < t_HFGen; i++) {
1312 X_low[k][i][0] = W[0][i + i_f - t_HFGen][k][0];
1313 X_low[k][i][1] = W[0][i + i_f - t_HFGen][k][1];
1319 /// High Frequency Generator (14496-3 sp04 p215)
1320 static int sbr_hf_gen(AACContext *ac, SpectralBandReplication *sbr,
1321 float X_high[64][40][2], const float X_low[32][40][2],
1322 const float (*alpha0)[2], const float (*alpha1)[2],
1323 const float bw_array[5], const uint8_t *t_env,
1329 for (j = 0; j < sbr->num_patches; j++) {
1330 for (x = 0; x < sbr->patch_num_subbands[j]; x++, k++) {
1331 const int p = sbr->patch_start_subband[j] + x;
1332 while (g <= sbr->n_q && k >= sbr->f_tablenoise[g])
1337 av_log(ac->avctx, AV_LOG_ERROR,
1338 "ERROR : no subband found for frequency %d\n", k);
1342 sbr->dsp.hf_gen(X_high[k] + ENVELOPE_ADJUSTMENT_OFFSET,
1343 X_low[p] + ENVELOPE_ADJUSTMENT_OFFSET,
1344 alpha0[p], alpha1[p], bw_array[g],
1345 2 * t_env[0], 2 * t_env[bs_num_env]);
1348 if (k < sbr->m[1] + sbr->kx[1])
1349 memset(X_high + k, 0, (sbr->m[1] + sbr->kx[1] - k) * sizeof(*X_high));
1354 /// Generate the subband filtered lowband
1355 static int sbr_x_gen(SpectralBandReplication *sbr, float X[2][38][64],
1356 const float X_low[32][40][2], const float Y[2][38][64][2],
1361 const int i_Temp = FFMAX(2*sbr->data[ch].t_env_num_env_old - i_f, 0);
1362 memset(X, 0, 2*sizeof(*X));
1363 for (k = 0; k < sbr->kx[0]; k++) {
1364 for (i = 0; i < i_Temp; i++) {
1365 X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1366 X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1369 for (; k < sbr->kx[0] + sbr->m[0]; k++) {
1370 for (i = 0; i < i_Temp; i++) {
1371 X[0][i][k] = Y[0][i + i_f][k][0];
1372 X[1][i][k] = Y[0][i + i_f][k][1];
1376 for (k = 0; k < sbr->kx[1]; k++) {
1377 for (i = i_Temp; i < 38; i++) {
1378 X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1379 X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1382 for (; k < sbr->kx[1] + sbr->m[1]; k++) {
1383 for (i = i_Temp; i < i_f; i++) {
1384 X[0][i][k] = Y[1][i][k][0];
1385 X[1][i][k] = Y[1][i][k][1];
1391 /** High Frequency Adjustment (14496-3 sp04 p217) and Mapping
1392 * (14496-3 sp04 p217)
1394 static void sbr_mapping(AACContext *ac, SpectralBandReplication *sbr,
1395 SBRData *ch_data, int e_a[2])
1399 memset(ch_data->s_indexmapped[1], 0, 7*sizeof(ch_data->s_indexmapped[1]));
1400 for (e = 0; e < ch_data->bs_num_env; e++) {
1401 const unsigned int ilim = sbr->n[ch_data->bs_freq_res[e + 1]];
1402 uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1405 av_assert0(sbr->kx[1] <= table[0]);
1406 for (i = 0; i < ilim; i++)
1407 for (m = table[i]; m < table[i + 1]; m++)
1408 sbr->e_origmapped[e][m - sbr->kx[1]] = ch_data->env_facs[e+1][i];
1410 // ch_data->bs_num_noise > 1 => 2 noise floors
1411 k = (ch_data->bs_num_noise > 1) && (ch_data->t_env[e] >= ch_data->t_q[1]);
1412 for (i = 0; i < sbr->n_q; i++)
1413 for (m = sbr->f_tablenoise[i]; m < sbr->f_tablenoise[i + 1]; m++)
1414 sbr->q_mapped[e][m - sbr->kx[1]] = ch_data->noise_facs[k+1][i];
1416 for (i = 0; i < sbr->n[1]; i++) {
1417 if (ch_data->bs_add_harmonic_flag) {
1418 const unsigned int m_midpoint =
1419 (sbr->f_tablehigh[i] + sbr->f_tablehigh[i + 1]) >> 1;
1421 ch_data->s_indexmapped[e + 1][m_midpoint - sbr->kx[1]] = ch_data->bs_add_harmonic[i] *
1422 (e >= e_a[1] || (ch_data->s_indexmapped[0][m_midpoint - sbr->kx[1]] == 1));
1426 for (i = 0; i < ilim; i++) {
1427 int additional_sinusoid_present = 0;
1428 for (m = table[i]; m < table[i + 1]; m++) {
1429 if (ch_data->s_indexmapped[e + 1][m - sbr->kx[1]]) {
1430 additional_sinusoid_present = 1;
1434 memset(&sbr->s_mapped[e][table[i] - sbr->kx[1]], additional_sinusoid_present,
1435 (table[i + 1] - table[i]) * sizeof(sbr->s_mapped[e][0]));
1439 memcpy(ch_data->s_indexmapped[0], ch_data->s_indexmapped[ch_data->bs_num_env], sizeof(ch_data->s_indexmapped[0]));
1442 /// Estimation of current envelope (14496-3 sp04 p218)
1443 static void sbr_env_estimate(float (*e_curr)[48], float X_high[64][40][2],
1444 SpectralBandReplication *sbr, SBRData *ch_data)
1447 int kx1 = sbr->kx[1];
1449 if (sbr->bs_interpol_freq) {
1450 for (e = 0; e < ch_data->bs_num_env; e++) {
1451 const float recip_env_size = 0.5f / (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1452 int ilb = ch_data->t_env[e] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1453 int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1455 for (m = 0; m < sbr->m[1]; m++) {
1456 float sum = sbr->dsp.sum_square(X_high[m+kx1] + ilb, iub - ilb);
1457 e_curr[e][m] = sum * recip_env_size;
1463 for (e = 0; e < ch_data->bs_num_env; e++) {
1464 const int env_size = 2 * (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1465 int ilb = ch_data->t_env[e] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1466 int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1467 const uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1469 for (p = 0; p < sbr->n[ch_data->bs_freq_res[e + 1]]; p++) {
1471 const int den = env_size * (table[p + 1] - table[p]);
1473 for (k = table[p]; k < table[p + 1]; k++) {
1474 sum += sbr->dsp.sum_square(X_high[k] + ilb, iub - ilb);
1477 for (k = table[p]; k < table[p + 1]; k++) {
1478 e_curr[e][k - kx1] = sum;
1486 * Calculation of levels of additional HF signal components (14496-3 sp04 p219)
1487 * and Calculation of gain (14496-3 sp04 p219)
1489 static void sbr_gain_calc(AACContext *ac, SpectralBandReplication *sbr,
1490 SBRData *ch_data, const int e_a[2])
1493 // max gain limits : -3dB, 0dB, 3dB, inf dB (limiter off)
1494 static const float limgain[4] = { 0.70795, 1.0, 1.41254, 10000000000 };
1496 for (e = 0; e < ch_data->bs_num_env; e++) {
1497 int delta = !((e == e_a[1]) || (e == e_a[0]));
1498 for (k = 0; k < sbr->n_lim; k++) {
1499 float gain_boost, gain_max;
1500 float sum[2] = { 0.0f, 0.0f };
1501 for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1502 const float temp = sbr->e_origmapped[e][m] / (1.0f + sbr->q_mapped[e][m]);
1503 sbr->q_m[e][m] = sqrtf(temp * sbr->q_mapped[e][m]);
1504 sbr->s_m[e][m] = sqrtf(temp * ch_data->s_indexmapped[e + 1][m]);
1505 if (!sbr->s_mapped[e][m]) {
1506 sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] /
1507 ((1.0f + sbr->e_curr[e][m]) *
1508 (1.0f + sbr->q_mapped[e][m] * delta)));
1510 sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] * sbr->q_mapped[e][m] /
1511 ((1.0f + sbr->e_curr[e][m]) *
1512 (1.0f + sbr->q_mapped[e][m])));
1515 for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1516 sum[0] += sbr->e_origmapped[e][m];
1517 sum[1] += sbr->e_curr[e][m];
1519 gain_max = limgain[sbr->bs_limiter_gains] * sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
1520 gain_max = FFMIN(100000.f, gain_max);
1521 for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1522 float q_m_max = sbr->q_m[e][m] * gain_max / sbr->gain[e][m];
1523 sbr->q_m[e][m] = FFMIN(sbr->q_m[e][m], q_m_max);
1524 sbr->gain[e][m] = FFMIN(sbr->gain[e][m], gain_max);
1526 sum[0] = sum[1] = 0.0f;
1527 for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1528 sum[0] += sbr->e_origmapped[e][m];
1529 sum[1] += sbr->e_curr[e][m] * sbr->gain[e][m] * sbr->gain[e][m]
1530 + sbr->s_m[e][m] * sbr->s_m[e][m]
1531 + (delta && !sbr->s_m[e][m]) * sbr->q_m[e][m] * sbr->q_m[e][m];
1533 gain_boost = sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
1534 gain_boost = FFMIN(1.584893192f, gain_boost);
1535 for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1536 sbr->gain[e][m] *= gain_boost;
1537 sbr->q_m[e][m] *= gain_boost;
1538 sbr->s_m[e][m] *= gain_boost;
1544 /// Assembling HF Signals (14496-3 sp04 p220)
1545 static void sbr_hf_assemble(float Y[2][38][64][2], const float X_high[64][40][2],
1546 SpectralBandReplication *sbr, SBRData *ch_data,
1550 const int h_SL = 4 * !sbr->bs_smoothing_mode;
1551 const int kx = sbr->kx[1];
1552 const int m_max = sbr->m[1];
1553 static const float h_smooth[5] = {
1560 static const int8_t phi[2][4] = {
1561 { 1, 0, -1, 0}, // real
1562 { 0, 1, 0, -1}, // imaginary
1564 float (*g_temp)[48] = ch_data->g_temp, (*q_temp)[48] = ch_data->q_temp;
1565 int indexnoise = ch_data->f_indexnoise;
1566 int indexsine = ch_data->f_indexsine;
1567 memcpy(Y[0], Y[1], sizeof(Y[0]));
1570 for (i = 0; i < h_SL; i++) {
1571 memcpy(g_temp[i + 2*ch_data->t_env[0]], sbr->gain[0], m_max * sizeof(sbr->gain[0][0]));
1572 memcpy(q_temp[i + 2*ch_data->t_env[0]], sbr->q_m[0], m_max * sizeof(sbr->q_m[0][0]));
1575 memcpy(g_temp[2*ch_data->t_env[0]], g_temp[2*ch_data->t_env_num_env_old], 4*sizeof(g_temp[0]));
1576 memcpy(q_temp[2*ch_data->t_env[0]], q_temp[2*ch_data->t_env_num_env_old], 4*sizeof(q_temp[0]));
1579 for (e = 0; e < ch_data->bs_num_env; e++) {
1580 for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
1581 memcpy(g_temp[h_SL + i], sbr->gain[e], m_max * sizeof(sbr->gain[0][0]));
1582 memcpy(q_temp[h_SL + i], sbr->q_m[e], m_max * sizeof(sbr->q_m[0][0]));
1586 for (e = 0; e < ch_data->bs_num_env; e++) {
1587 for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
1588 int phi_sign = (1 - 2*(kx & 1));
1589 LOCAL_ALIGNED_16(float, g_filt_tab, [48]);
1590 LOCAL_ALIGNED_16(float, q_filt_tab, [48]);
1591 float *g_filt, *q_filt;
1593 if (h_SL && e != e_a[0] && e != e_a[1]) {
1594 g_filt = g_filt_tab;
1595 q_filt = q_filt_tab;
1596 for (m = 0; m < m_max; m++) {
1597 const int idx1 = i + h_SL;
1600 for (j = 0; j <= h_SL; j++) {
1601 g_filt[m] += g_temp[idx1 - j][m] * h_smooth[j];
1602 q_filt[m] += q_temp[idx1 - j][m] * h_smooth[j];
1606 g_filt = g_temp[i + h_SL];
1610 sbr->dsp.hf_g_filt(Y[1][i] + kx, X_high + kx, g_filt, m_max,
1611 i + ENVELOPE_ADJUSTMENT_OFFSET);
1613 if (e != e_a[0] && e != e_a[1]) {
1614 sbr->dsp.hf_apply_noise[indexsine](Y[1][i] + kx, sbr->s_m[e],
1618 for (m = 0; m < m_max; m++) {
1619 Y[1][i][m + kx][0] +=
1620 sbr->s_m[e][m] * phi[0][indexsine];
1621 Y[1][i][m + kx][1] +=
1622 sbr->s_m[e][m] * (phi[1][indexsine] * phi_sign);
1623 phi_sign = -phi_sign;
1626 indexnoise = (indexnoise + m_max) & 0x1ff;
1627 indexsine = (indexsine + 1) & 3;
1630 ch_data->f_indexnoise = indexnoise;
1631 ch_data->f_indexsine = indexsine;
1634 void ff_sbr_apply(AACContext *ac, SpectralBandReplication *sbr, int id_aac,
1637 int downsampled = ac->m4ac.ext_sample_rate < sbr->sample_rate;
1639 int nch = (id_aac == TYPE_CPE) ? 2 : 1;
1642 sbr_dequant(sbr, id_aac);
1644 for (ch = 0; ch < nch; ch++) {
1645 /* decode channel */
1646 sbr_qmf_analysis(&ac->dsp, &sbr->mdct_ana, &sbr->dsp, ch ? R : L, sbr->data[ch].analysis_filterbank_samples,
1647 (float*)sbr->qmf_filter_scratch,
1649 sbr_lf_gen(ac, sbr, sbr->X_low, sbr->data[ch].W);
1651 sbr_hf_inverse_filter(&sbr->dsp, sbr->alpha0, sbr->alpha1, sbr->X_low, sbr->k[0]);
1652 sbr_chirp(sbr, &sbr->data[ch]);
1653 sbr_hf_gen(ac, sbr, sbr->X_high, sbr->X_low, sbr->alpha0, sbr->alpha1,
1654 sbr->data[ch].bw_array, sbr->data[ch].t_env,
1655 sbr->data[ch].bs_num_env);
1658 sbr_mapping(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1659 sbr_env_estimate(sbr->e_curr, sbr->X_high, sbr, &sbr->data[ch]);
1660 sbr_gain_calc(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1661 sbr_hf_assemble(sbr->data[ch].Y, sbr->X_high, sbr, &sbr->data[ch],
1666 sbr_x_gen(sbr, sbr->X[ch], sbr->X_low, sbr->data[ch].Y, ch);
1669 if (ac->m4ac.ps == 1) {
1670 if (sbr->ps.start) {
1671 ff_ps_apply(ac->avctx, &sbr->ps, sbr->X[0], sbr->X[1], sbr->kx[1] + sbr->m[1]);
1673 memcpy(sbr->X[1], sbr->X[0], sizeof(sbr->X[0]));
1678 sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, &sbr->dsp, L, sbr->X[0], sbr->qmf_filter_scratch,
1679 sbr->data[0].synthesis_filterbank_samples,
1680 &sbr->data[0].synthesis_filterbank_samples_offset,
1683 sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, &sbr->dsp, R, sbr->X[1], sbr->qmf_filter_scratch,
1684 sbr->data[1].synthesis_filterbank_samples,
1685 &sbr->data[1].synthesis_filterbank_samples_offset,