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 Libav.
8 * Libav is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
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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"
41 #define ENVELOPE_ADJUSTMENT_OFFSET 2
42 #define NOISE_FLOOR_OFFSET 6.0f
50 T_HUFFMAN_ENV_BAL_1_5DB,
51 F_HUFFMAN_ENV_BAL_1_5DB,
54 T_HUFFMAN_ENV_BAL_3_0DB,
55 F_HUFFMAN_ENV_BAL_3_0DB,
56 T_HUFFMAN_NOISE_3_0DB,
57 T_HUFFMAN_NOISE_BAL_3_0DB,
61 * bs_frame_class - frame class of current SBR frame (14496-3 sp04 p98)
74 static VLC vlc_sbr[10];
75 static const int8_t vlc_sbr_lav[10] =
76 { 60, 60, 24, 24, 31, 31, 12, 12, 31, 12 };
78 #define SBR_INIT_VLC_STATIC(num, size) \
79 INIT_VLC_STATIC(&vlc_sbr[num], 9, sbr_tmp[num].table_size / sbr_tmp[num].elem_size, \
80 sbr_tmp[num].sbr_bits , 1, 1, \
81 sbr_tmp[num].sbr_codes, sbr_tmp[num].elem_size, sbr_tmp[num].elem_size, \
84 #define SBR_VLC_ROW(name) \
85 { name ## _codes, name ## _bits, sizeof(name ## _codes), sizeof(name ## _codes[0]) }
87 av_cold void ff_aac_sbr_init(void)
91 const void *sbr_codes, *sbr_bits;
92 const unsigned int table_size, elem_size;
94 SBR_VLC_ROW(t_huffman_env_1_5dB),
95 SBR_VLC_ROW(f_huffman_env_1_5dB),
96 SBR_VLC_ROW(t_huffman_env_bal_1_5dB),
97 SBR_VLC_ROW(f_huffman_env_bal_1_5dB),
98 SBR_VLC_ROW(t_huffman_env_3_0dB),
99 SBR_VLC_ROW(f_huffman_env_3_0dB),
100 SBR_VLC_ROW(t_huffman_env_bal_3_0dB),
101 SBR_VLC_ROW(f_huffman_env_bal_3_0dB),
102 SBR_VLC_ROW(t_huffman_noise_3_0dB),
103 SBR_VLC_ROW(t_huffman_noise_bal_3_0dB),
106 // SBR VLC table initialization
107 SBR_INIT_VLC_STATIC(0, 1098);
108 SBR_INIT_VLC_STATIC(1, 1092);
109 SBR_INIT_VLC_STATIC(2, 768);
110 SBR_INIT_VLC_STATIC(3, 1026);
111 SBR_INIT_VLC_STATIC(4, 1058);
112 SBR_INIT_VLC_STATIC(5, 1052);
113 SBR_INIT_VLC_STATIC(6, 544);
114 SBR_INIT_VLC_STATIC(7, 544);
115 SBR_INIT_VLC_STATIC(8, 592);
116 SBR_INIT_VLC_STATIC(9, 512);
118 for (n = 1; n < 320; n++)
119 sbr_qmf_window_us[320 + n] = sbr_qmf_window_us[320 - n];
120 sbr_qmf_window_us[384] = -sbr_qmf_window_us[384];
121 sbr_qmf_window_us[512] = -sbr_qmf_window_us[512];
123 for (n = 0; n < 320; n++)
124 sbr_qmf_window_ds[n] = sbr_qmf_window_us[2*n];
129 /** Places SBR in pure upsampling mode. */
130 static void sbr_turnoff(SpectralBandReplication *sbr) {
132 // Init defults used in pure upsampling mode
133 sbr->kx[1] = 32; //Typo in spec, kx' inits to 32
135 // Reset values for first SBR header
136 sbr->data[0].e_a[1] = sbr->data[1].e_a[1] = -1;
137 memset(&sbr->spectrum_params, -1, sizeof(SpectrumParameters));
140 av_cold void ff_aac_sbr_ctx_init(AACContext *ac, SpectralBandReplication *sbr)
142 sbr->kx[0] = sbr->kx[1];
144 sbr->data[0].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
145 sbr->data[1].synthesis_filterbank_samples_offset = SBR_SYNTHESIS_BUF_SIZE - (1280 - 128);
146 /* SBR requires samples to be scaled to +/-32768.0 to work correctly.
147 * mdct scale factors are adjusted to scale up from +/-1.0 at analysis
148 * and scale back down at synthesis. */
149 ff_mdct_init(&sbr->mdct, 7, 1, 1.0 / (64 * 32768.0));
150 ff_mdct_init(&sbr->mdct_ana, 7, 1, -2.0 * 32768.0);
151 ff_ps_ctx_init(&sbr->ps);
152 ff_sbrdsp_init(&sbr->dsp);
155 av_cold void ff_aac_sbr_ctx_close(SpectralBandReplication *sbr)
157 ff_mdct_end(&sbr->mdct);
158 ff_mdct_end(&sbr->mdct_ana);
161 static int qsort_comparison_function_int16(const void *a, const void *b)
163 return *(const int16_t *)a - *(const int16_t *)b;
166 static inline int in_table_int16(const int16_t *table, int last_el, int16_t needle)
169 for (i = 0; i <= last_el; i++)
170 if (table[i] == needle)
175 /// Limiter Frequency Band Table (14496-3 sp04 p198)
176 static void sbr_make_f_tablelim(SpectralBandReplication *sbr)
179 if (sbr->bs_limiter_bands > 0) {
180 static const float bands_warped[3] = { 1.32715174233856803909f, //2^(0.49/1.2)
181 1.18509277094158210129f, //2^(0.49/2)
182 1.11987160404675912501f }; //2^(0.49/3)
183 const float lim_bands_per_octave_warped = bands_warped[sbr->bs_limiter_bands - 1];
184 int16_t patch_borders[7];
185 uint16_t *in = sbr->f_tablelim + 1, *out = sbr->f_tablelim;
187 patch_borders[0] = sbr->kx[1];
188 for (k = 1; k <= sbr->num_patches; k++)
189 patch_borders[k] = patch_borders[k-1] + sbr->patch_num_subbands[k-1];
191 memcpy(sbr->f_tablelim, sbr->f_tablelow,
192 (sbr->n[0] + 1) * sizeof(sbr->f_tablelow[0]));
193 if (sbr->num_patches > 1)
194 memcpy(sbr->f_tablelim + sbr->n[0] + 1, patch_borders + 1,
195 (sbr->num_patches - 1) * sizeof(patch_borders[0]));
197 qsort(sbr->f_tablelim, sbr->num_patches + sbr->n[0],
198 sizeof(sbr->f_tablelim[0]),
199 qsort_comparison_function_int16);
201 sbr->n_lim = sbr->n[0] + sbr->num_patches - 1;
202 while (out < sbr->f_tablelim + sbr->n_lim) {
203 if (*in >= *out * lim_bands_per_octave_warped) {
205 } else if (*in == *out ||
206 !in_table_int16(patch_borders, sbr->num_patches, *in)) {
209 } else if (!in_table_int16(patch_borders, sbr->num_patches, *out)) {
217 sbr->f_tablelim[0] = sbr->f_tablelow[0];
218 sbr->f_tablelim[1] = sbr->f_tablelow[sbr->n[0]];
223 static unsigned int read_sbr_header(SpectralBandReplication *sbr, GetBitContext *gb)
225 unsigned int cnt = get_bits_count(gb);
226 uint8_t bs_header_extra_1;
227 uint8_t bs_header_extra_2;
228 int old_bs_limiter_bands = sbr->bs_limiter_bands;
229 SpectrumParameters old_spectrum_params;
233 // Save last spectrum parameters variables to compare to new ones
234 memcpy(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters));
236 sbr->bs_amp_res_header = get_bits1(gb);
237 sbr->spectrum_params.bs_start_freq = get_bits(gb, 4);
238 sbr->spectrum_params.bs_stop_freq = get_bits(gb, 4);
239 sbr->spectrum_params.bs_xover_band = get_bits(gb, 3);
240 skip_bits(gb, 2); // bs_reserved
242 bs_header_extra_1 = get_bits1(gb);
243 bs_header_extra_2 = get_bits1(gb);
245 if (bs_header_extra_1) {
246 sbr->spectrum_params.bs_freq_scale = get_bits(gb, 2);
247 sbr->spectrum_params.bs_alter_scale = get_bits1(gb);
248 sbr->spectrum_params.bs_noise_bands = get_bits(gb, 2);
250 sbr->spectrum_params.bs_freq_scale = 2;
251 sbr->spectrum_params.bs_alter_scale = 1;
252 sbr->spectrum_params.bs_noise_bands = 2;
255 // Check if spectrum parameters changed
256 if (memcmp(&old_spectrum_params, &sbr->spectrum_params, sizeof(SpectrumParameters)))
259 if (bs_header_extra_2) {
260 sbr->bs_limiter_bands = get_bits(gb, 2);
261 sbr->bs_limiter_gains = get_bits(gb, 2);
262 sbr->bs_interpol_freq = get_bits1(gb);
263 sbr->bs_smoothing_mode = get_bits1(gb);
265 sbr->bs_limiter_bands = 2;
266 sbr->bs_limiter_gains = 2;
267 sbr->bs_interpol_freq = 1;
268 sbr->bs_smoothing_mode = 1;
271 if (sbr->bs_limiter_bands != old_bs_limiter_bands && !sbr->reset)
272 sbr_make_f_tablelim(sbr);
274 return get_bits_count(gb) - cnt;
277 static int array_min_int16(const int16_t *array, int nel)
279 int i, min = array[0];
280 for (i = 1; i < nel; i++)
281 min = FFMIN(array[i], min);
285 static void make_bands(int16_t* bands, int start, int stop, int num_bands)
287 int k, previous, present;
290 base = powf((float)stop / start, 1.0f / num_bands);
294 for (k = 0; k < num_bands-1; k++) {
296 present = lrintf(prod);
297 bands[k] = present - previous;
300 bands[num_bands-1] = stop - previous;
303 static int check_n_master(AVCodecContext *avctx, int n_master, int bs_xover_band)
305 // Requirements (14496-3 sp04 p205)
307 av_log(avctx, AV_LOG_ERROR, "Invalid n_master: %d\n", n_master);
310 if (bs_xover_band >= n_master) {
311 av_log(avctx, AV_LOG_ERROR,
312 "Invalid bitstream, crossover band index beyond array bounds: %d\n",
319 /// Master Frequency Band Table (14496-3 sp04 p194)
320 static int sbr_make_f_master(AACContext *ac, SpectralBandReplication *sbr,
321 SpectrumParameters *spectrum)
323 unsigned int temp, max_qmf_subbands;
324 unsigned int start_min, stop_min;
326 const int8_t *sbr_offset_ptr;
329 if (sbr->sample_rate < 32000) {
331 } else if (sbr->sample_rate < 64000) {
336 start_min = ((temp << 7) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
337 stop_min = ((temp << 8) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
339 switch (sbr->sample_rate) {
341 sbr_offset_ptr = sbr_offset[0];
344 sbr_offset_ptr = sbr_offset[1];
347 sbr_offset_ptr = sbr_offset[2];
350 sbr_offset_ptr = sbr_offset[3];
352 case 44100: case 48000: case 64000:
353 sbr_offset_ptr = sbr_offset[4];
355 case 88200: case 96000: case 128000: case 176400: case 192000:
356 sbr_offset_ptr = sbr_offset[5];
359 av_log(ac->avctx, AV_LOG_ERROR,
360 "Unsupported sample rate for SBR: %d\n", sbr->sample_rate);
364 sbr->k[0] = start_min + sbr_offset_ptr[spectrum->bs_start_freq];
366 if (spectrum->bs_stop_freq < 14) {
367 sbr->k[2] = stop_min;
368 make_bands(stop_dk, stop_min, 64, 13);
369 qsort(stop_dk, 13, sizeof(stop_dk[0]), qsort_comparison_function_int16);
370 for (k = 0; k < spectrum->bs_stop_freq; k++)
371 sbr->k[2] += stop_dk[k];
372 } else if (spectrum->bs_stop_freq == 14) {
373 sbr->k[2] = 2*sbr->k[0];
374 } else if (spectrum->bs_stop_freq == 15) {
375 sbr->k[2] = 3*sbr->k[0];
377 av_log(ac->avctx, AV_LOG_ERROR,
378 "Invalid bs_stop_freq: %d\n", spectrum->bs_stop_freq);
381 sbr->k[2] = FFMIN(64, sbr->k[2]);
383 // Requirements (14496-3 sp04 p205)
384 if (sbr->sample_rate <= 32000) {
385 max_qmf_subbands = 48;
386 } else if (sbr->sample_rate == 44100) {
387 max_qmf_subbands = 35;
388 } else if (sbr->sample_rate >= 48000)
389 max_qmf_subbands = 32;
391 if (sbr->k[2] - sbr->k[0] > max_qmf_subbands) {
392 av_log(ac->avctx, AV_LOG_ERROR,
393 "Invalid bitstream, too many QMF subbands: %d\n", sbr->k[2] - sbr->k[0]);
397 if (!spectrum->bs_freq_scale) {
400 dk = spectrum->bs_alter_scale + 1;
401 sbr->n_master = ((sbr->k[2] - sbr->k[0] + (dk&2)) >> dk) << 1;
402 if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
405 for (k = 1; k <= sbr->n_master; k++)
406 sbr->f_master[k] = dk;
408 k2diff = sbr->k[2] - sbr->k[0] - sbr->n_master * dk;
411 sbr->f_master[2]-= (k2diff < -1);
413 sbr->f_master[sbr->n_master]++;
416 sbr->f_master[0] = sbr->k[0];
417 for (k = 1; k <= sbr->n_master; k++)
418 sbr->f_master[k] += sbr->f_master[k - 1];
421 int half_bands = 7 - spectrum->bs_freq_scale; // bs_freq_scale = {1,2,3}
422 int two_regions, num_bands_0;
423 int vdk0_max, vdk1_min;
426 if (49 * sbr->k[2] > 110 * sbr->k[0]) {
428 sbr->k[1] = 2 * sbr->k[0];
431 sbr->k[1] = sbr->k[2];
434 num_bands_0 = lrintf(half_bands * log2f(sbr->k[1] / (float)sbr->k[0])) * 2;
436 if (num_bands_0 <= 0) { // Requirements (14496-3 sp04 p205)
437 av_log(ac->avctx, AV_LOG_ERROR, "Invalid num_bands_0: %d\n", num_bands_0);
443 make_bands(vk0+1, sbr->k[0], sbr->k[1], num_bands_0);
445 qsort(vk0 + 1, num_bands_0, sizeof(vk0[1]), qsort_comparison_function_int16);
446 vdk0_max = vk0[num_bands_0];
449 for (k = 1; k <= num_bands_0; k++) {
450 if (vk0[k] <= 0) { // Requirements (14496-3 sp04 p205)
451 av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk0[%d]: %d\n", k, vk0[k]);
459 float invwarp = spectrum->bs_alter_scale ? 0.76923076923076923077f
460 : 1.0f; // bs_alter_scale = {0,1}
461 int num_bands_1 = lrintf(half_bands * invwarp *
462 log2f(sbr->k[2] / (float)sbr->k[1])) * 2;
464 make_bands(vk1+1, sbr->k[1], sbr->k[2], num_bands_1);
466 vdk1_min = array_min_int16(vk1 + 1, num_bands_1);
468 if (vdk1_min < vdk0_max) {
470 qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
471 change = FFMIN(vdk0_max - vk1[1], (vk1[num_bands_1] - vk1[1]) >> 1);
473 vk1[num_bands_1] -= change;
476 qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]), qsort_comparison_function_int16);
479 for (k = 1; k <= num_bands_1; k++) {
480 if (vk1[k] <= 0) { // Requirements (14496-3 sp04 p205)
481 av_log(ac->avctx, AV_LOG_ERROR, "Invalid vDk1[%d]: %d\n", k, vk1[k]);
487 sbr->n_master = num_bands_0 + num_bands_1;
488 if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
490 memcpy(&sbr->f_master[0], vk0,
491 (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
492 memcpy(&sbr->f_master[num_bands_0 + 1], vk1 + 1,
493 num_bands_1 * sizeof(sbr->f_master[0]));
496 sbr->n_master = num_bands_0;
497 if (check_n_master(ac->avctx, sbr->n_master, sbr->spectrum_params.bs_xover_band))
499 memcpy(sbr->f_master, vk0, (num_bands_0 + 1) * sizeof(sbr->f_master[0]));
506 /// High Frequency Generation - Patch Construction (14496-3 sp04 p216 fig. 4.46)
507 static int sbr_hf_calc_npatches(AACContext *ac, SpectralBandReplication *sbr)
511 int usb = sbr->kx[1];
512 int goal_sb = ((1000 << 11) + (sbr->sample_rate >> 1)) / sbr->sample_rate;
514 sbr->num_patches = 0;
516 if (goal_sb < sbr->kx[1] + sbr->m[1]) {
517 for (k = 0; sbr->f_master[k] < goal_sb; k++) ;
523 for (i = k; i == k || sb > (sbr->k[0] - 1 + msb - odd); i--) {
524 sb = sbr->f_master[i];
525 odd = (sb + sbr->k[0]) & 1;
528 // Requirements (14496-3 sp04 p205) sets the maximum number of patches to 5.
529 // After this check the final number of patches can still be six which is
530 // illegal however the Coding Technologies decoder check stream has a final
531 // count of 6 patches
532 if (sbr->num_patches > 5) {
533 av_log(ac->avctx, AV_LOG_ERROR, "Too many patches: %d\n", sbr->num_patches);
537 sbr->patch_num_subbands[sbr->num_patches] = FFMAX(sb - usb, 0);
538 sbr->patch_start_subband[sbr->num_patches] = sbr->k[0] - odd - sbr->patch_num_subbands[sbr->num_patches];
540 if (sbr->patch_num_subbands[sbr->num_patches] > 0) {
547 if (sbr->f_master[k] - sb < 3)
549 } while (sb != sbr->kx[1] + sbr->m[1]);
551 if (sbr->patch_num_subbands[sbr->num_patches-1] < 3 && sbr->num_patches > 1)
557 /// Derived Frequency Band Tables (14496-3 sp04 p197)
558 static int sbr_make_f_derived(AACContext *ac, SpectralBandReplication *sbr)
562 sbr->n[1] = sbr->n_master - sbr->spectrum_params.bs_xover_band;
563 sbr->n[0] = (sbr->n[1] + 1) >> 1;
565 memcpy(sbr->f_tablehigh, &sbr->f_master[sbr->spectrum_params.bs_xover_band],
566 (sbr->n[1] + 1) * sizeof(sbr->f_master[0]));
567 sbr->m[1] = sbr->f_tablehigh[sbr->n[1]] - sbr->f_tablehigh[0];
568 sbr->kx[1] = sbr->f_tablehigh[0];
570 // Requirements (14496-3 sp04 p205)
571 if (sbr->kx[1] + sbr->m[1] > 64) {
572 av_log(ac->avctx, AV_LOG_ERROR,
573 "Stop frequency border too high: %d\n", sbr->kx[1] + sbr->m[1]);
576 if (sbr->kx[1] > 32) {
577 av_log(ac->avctx, AV_LOG_ERROR, "Start frequency border too high: %d\n", sbr->kx[1]);
581 sbr->f_tablelow[0] = sbr->f_tablehigh[0];
582 temp = sbr->n[1] & 1;
583 for (k = 1; k <= sbr->n[0]; k++)
584 sbr->f_tablelow[k] = sbr->f_tablehigh[2 * k - temp];
586 sbr->n_q = FFMAX(1, lrintf(sbr->spectrum_params.bs_noise_bands *
587 log2f(sbr->k[2] / (float)sbr->kx[1]))); // 0 <= bs_noise_bands <= 3
589 av_log(ac->avctx, AV_LOG_ERROR, "Too many noise floor scale factors: %d\n", sbr->n_q);
593 sbr->f_tablenoise[0] = sbr->f_tablelow[0];
595 for (k = 1; k <= sbr->n_q; k++) {
596 temp += (sbr->n[0] - temp) / (sbr->n_q + 1 - k);
597 sbr->f_tablenoise[k] = sbr->f_tablelow[temp];
600 if (sbr_hf_calc_npatches(ac, sbr) < 0)
603 sbr_make_f_tablelim(sbr);
605 sbr->data[0].f_indexnoise = 0;
606 sbr->data[1].f_indexnoise = 0;
611 static av_always_inline void get_bits1_vector(GetBitContext *gb, uint8_t *vec,
615 for (i = 0; i < elements; i++) {
616 vec[i] = get_bits1(gb);
620 /** ceil(log2(index+1)) */
621 static const int8_t ceil_log2[] = {
625 static int read_sbr_grid(AACContext *ac, SpectralBandReplication *sbr,
626 GetBitContext *gb, SBRData *ch_data)
629 unsigned bs_pointer = 0;
630 // frameLengthFlag ? 15 : 16; 960 sample length frames unsupported; this value is numTimeSlots
631 int abs_bord_trail = 16;
632 int num_rel_lead, num_rel_trail;
633 unsigned bs_num_env_old = ch_data->bs_num_env;
635 ch_data->bs_freq_res[0] = ch_data->bs_freq_res[ch_data->bs_num_env];
636 ch_data->bs_amp_res = sbr->bs_amp_res_header;
637 ch_data->t_env_num_env_old = ch_data->t_env[bs_num_env_old];
639 switch (ch_data->bs_frame_class = get_bits(gb, 2)) {
641 ch_data->bs_num_env = 1 << get_bits(gb, 2);
642 num_rel_lead = ch_data->bs_num_env - 1;
643 if (ch_data->bs_num_env == 1)
644 ch_data->bs_amp_res = 0;
646 if (ch_data->bs_num_env > 4) {
647 av_log(ac->avctx, AV_LOG_ERROR,
648 "Invalid bitstream, too many SBR envelopes in FIXFIX type SBR frame: %d\n",
649 ch_data->bs_num_env);
653 ch_data->t_env[0] = 0;
654 ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
656 abs_bord_trail = (abs_bord_trail + (ch_data->bs_num_env >> 1)) /
658 for (i = 0; i < num_rel_lead; i++)
659 ch_data->t_env[i + 1] = ch_data->t_env[i] + abs_bord_trail;
661 ch_data->bs_freq_res[1] = get_bits1(gb);
662 for (i = 1; i < ch_data->bs_num_env; i++)
663 ch_data->bs_freq_res[i + 1] = ch_data->bs_freq_res[1];
666 abs_bord_trail += get_bits(gb, 2);
667 num_rel_trail = get_bits(gb, 2);
668 ch_data->bs_num_env = num_rel_trail + 1;
669 ch_data->t_env[0] = 0;
670 ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
672 for (i = 0; i < num_rel_trail; i++)
673 ch_data->t_env[ch_data->bs_num_env - 1 - i] =
674 ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
676 bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
678 for (i = 0; i < ch_data->bs_num_env; i++)
679 ch_data->bs_freq_res[ch_data->bs_num_env - i] = get_bits1(gb);
682 ch_data->t_env[0] = get_bits(gb, 2);
683 num_rel_lead = get_bits(gb, 2);
684 ch_data->bs_num_env = num_rel_lead + 1;
685 ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
687 for (i = 0; i < num_rel_lead; i++)
688 ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
690 bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
692 get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
695 ch_data->t_env[0] = get_bits(gb, 2);
696 abs_bord_trail += get_bits(gb, 2);
697 num_rel_lead = get_bits(gb, 2);
698 num_rel_trail = get_bits(gb, 2);
699 ch_data->bs_num_env = num_rel_lead + num_rel_trail + 1;
701 if (ch_data->bs_num_env > 5) {
702 av_log(ac->avctx, AV_LOG_ERROR,
703 "Invalid bitstream, too many SBR envelopes in VARVAR type SBR frame: %d\n",
704 ch_data->bs_num_env);
708 ch_data->t_env[ch_data->bs_num_env] = abs_bord_trail;
710 for (i = 0; i < num_rel_lead; i++)
711 ch_data->t_env[i + 1] = ch_data->t_env[i] + 2 * get_bits(gb, 2) + 2;
712 for (i = 0; i < num_rel_trail; i++)
713 ch_data->t_env[ch_data->bs_num_env - 1 - i] =
714 ch_data->t_env[ch_data->bs_num_env - i] - 2 * get_bits(gb, 2) - 2;
716 bs_pointer = get_bits(gb, ceil_log2[ch_data->bs_num_env]);
718 get_bits1_vector(gb, ch_data->bs_freq_res + 1, ch_data->bs_num_env);
722 if (bs_pointer > ch_data->bs_num_env + 1) {
723 av_log(ac->avctx, AV_LOG_ERROR,
724 "Invalid bitstream, bs_pointer points to a middle noise border outside the time borders table: %d\n",
729 for (i = 1; i <= ch_data->bs_num_env; i++) {
730 if (ch_data->t_env[i-1] > ch_data->t_env[i]) {
731 av_log(ac->avctx, AV_LOG_ERROR, "Non monotone time borders\n");
736 ch_data->bs_num_noise = (ch_data->bs_num_env > 1) + 1;
738 ch_data->t_q[0] = ch_data->t_env[0];
739 ch_data->t_q[ch_data->bs_num_noise] = ch_data->t_env[ch_data->bs_num_env];
740 if (ch_data->bs_num_noise > 1) {
742 if (ch_data->bs_frame_class == FIXFIX) {
743 idx = ch_data->bs_num_env >> 1;
744 } else if (ch_data->bs_frame_class & 1) { // FIXVAR or VARVAR
745 idx = ch_data->bs_num_env - FFMAX(bs_pointer - 1, 1);
749 else if (bs_pointer == 1)
750 idx = ch_data->bs_num_env - 1;
751 else // bs_pointer > 1
752 idx = bs_pointer - 1;
754 ch_data->t_q[1] = ch_data->t_env[idx];
757 ch_data->e_a[0] = -(ch_data->e_a[1] != bs_num_env_old); // l_APrev
758 ch_data->e_a[1] = -1;
759 if ((ch_data->bs_frame_class & 1) && bs_pointer) { // FIXVAR or VARVAR and bs_pointer != 0
760 ch_data->e_a[1] = ch_data->bs_num_env + 1 - bs_pointer;
761 } else if ((ch_data->bs_frame_class == 2) && (bs_pointer > 1)) // VARFIX and bs_pointer > 1
762 ch_data->e_a[1] = bs_pointer - 1;
767 static void copy_sbr_grid(SBRData *dst, const SBRData *src) {
768 //These variables are saved from the previous frame rather than copied
769 dst->bs_freq_res[0] = dst->bs_freq_res[dst->bs_num_env];
770 dst->t_env_num_env_old = dst->t_env[dst->bs_num_env];
771 dst->e_a[0] = -(dst->e_a[1] != dst->bs_num_env);
773 //These variables are read from the bitstream and therefore copied
774 memcpy(dst->bs_freq_res+1, src->bs_freq_res+1, sizeof(dst->bs_freq_res)-sizeof(*dst->bs_freq_res));
775 memcpy(dst->t_env, src->t_env, sizeof(dst->t_env));
776 memcpy(dst->t_q, src->t_q, sizeof(dst->t_q));
777 dst->bs_num_env = src->bs_num_env;
778 dst->bs_amp_res = src->bs_amp_res;
779 dst->bs_num_noise = src->bs_num_noise;
780 dst->bs_frame_class = src->bs_frame_class;
781 dst->e_a[1] = src->e_a[1];
784 /// Read how the envelope and noise floor data is delta coded
785 static void read_sbr_dtdf(SpectralBandReplication *sbr, GetBitContext *gb,
788 get_bits1_vector(gb, ch_data->bs_df_env, ch_data->bs_num_env);
789 get_bits1_vector(gb, ch_data->bs_df_noise, ch_data->bs_num_noise);
792 /// Read inverse filtering data
793 static void read_sbr_invf(SpectralBandReplication *sbr, GetBitContext *gb,
798 memcpy(ch_data->bs_invf_mode[1], ch_data->bs_invf_mode[0], 5 * sizeof(uint8_t));
799 for (i = 0; i < sbr->n_q; i++)
800 ch_data->bs_invf_mode[0][i] = get_bits(gb, 2);
803 static void read_sbr_envelope(SpectralBandReplication *sbr, GetBitContext *gb,
804 SBRData *ch_data, int ch)
808 VLC_TYPE (*t_huff)[2], (*f_huff)[2];
810 const int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
811 const int odd = sbr->n[1] & 1;
813 if (sbr->bs_coupling && ch) {
814 if (ch_data->bs_amp_res) {
816 t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_3_0DB].table;
817 t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_3_0DB];
818 f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
819 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
822 t_huff = vlc_sbr[T_HUFFMAN_ENV_BAL_1_5DB].table;
823 t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_BAL_1_5DB];
824 f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_1_5DB].table;
825 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_1_5DB];
828 if (ch_data->bs_amp_res) {
830 t_huff = vlc_sbr[T_HUFFMAN_ENV_3_0DB].table;
831 t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_3_0DB];
832 f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
833 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
836 t_huff = vlc_sbr[T_HUFFMAN_ENV_1_5DB].table;
837 t_lav = vlc_sbr_lav[T_HUFFMAN_ENV_1_5DB];
838 f_huff = vlc_sbr[F_HUFFMAN_ENV_1_5DB].table;
839 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_1_5DB];
843 for (i = 0; i < ch_data->bs_num_env; i++) {
844 if (ch_data->bs_df_env[i]) {
845 // bs_freq_res[0] == bs_freq_res[bs_num_env] from prev frame
846 if (ch_data->bs_freq_res[i + 1] == ch_data->bs_freq_res[i]) {
847 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
848 ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
849 } else if (ch_data->bs_freq_res[i + 1]) {
850 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
851 k = (j + odd) >> 1; // find k such that f_tablelow[k] <= f_tablehigh[j] < f_tablelow[k + 1]
852 ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
855 for (j = 0; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++) {
856 k = j ? 2*j - odd : 0; // find k such that f_tablehigh[k] == f_tablelow[j]
857 ch_data->env_facs[i + 1][j] = ch_data->env_facs[i][k] + delta * (get_vlc2(gb, t_huff, 9, 3) - t_lav);
861 ch_data->env_facs[i + 1][0] = delta * get_bits(gb, bits); // bs_env_start_value_balance
862 for (j = 1; j < sbr->n[ch_data->bs_freq_res[i + 1]]; j++)
863 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);
867 //assign 0th elements of env_facs from last elements
868 memcpy(ch_data->env_facs[0], ch_data->env_facs[ch_data->bs_num_env],
869 sizeof(ch_data->env_facs[0]));
872 static void read_sbr_noise(SpectralBandReplication *sbr, GetBitContext *gb,
873 SBRData *ch_data, int ch)
876 VLC_TYPE (*t_huff)[2], (*f_huff)[2];
878 int delta = (ch == 1 && sbr->bs_coupling == 1) + 1;
880 if (sbr->bs_coupling && ch) {
881 t_huff = vlc_sbr[T_HUFFMAN_NOISE_BAL_3_0DB].table;
882 t_lav = vlc_sbr_lav[T_HUFFMAN_NOISE_BAL_3_0DB];
883 f_huff = vlc_sbr[F_HUFFMAN_ENV_BAL_3_0DB].table;
884 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_BAL_3_0DB];
886 t_huff = vlc_sbr[T_HUFFMAN_NOISE_3_0DB].table;
887 t_lav = vlc_sbr_lav[T_HUFFMAN_NOISE_3_0DB];
888 f_huff = vlc_sbr[F_HUFFMAN_ENV_3_0DB].table;
889 f_lav = vlc_sbr_lav[F_HUFFMAN_ENV_3_0DB];
892 for (i = 0; i < ch_data->bs_num_noise; i++) {
893 if (ch_data->bs_df_noise[i]) {
894 for (j = 0; j < sbr->n_q; j++)
895 ch_data->noise_facs[i + 1][j] = ch_data->noise_facs[i][j] + delta * (get_vlc2(gb, t_huff, 9, 2) - t_lav);
897 ch_data->noise_facs[i + 1][0] = delta * get_bits(gb, 5); // bs_noise_start_value_balance or bs_noise_start_value_level
898 for (j = 1; j < sbr->n_q; j++)
899 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);
903 //assign 0th elements of noise_facs from last elements
904 memcpy(ch_data->noise_facs[0], ch_data->noise_facs[ch_data->bs_num_noise],
905 sizeof(ch_data->noise_facs[0]));
908 static void read_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
910 int bs_extension_id, int *num_bits_left)
912 switch (bs_extension_id) {
913 case EXTENSION_ID_PS:
914 if (!ac->oc[1].m4ac.ps) {
915 av_log(ac->avctx, AV_LOG_ERROR, "Parametric Stereo signaled to be not-present but was found in the bitstream.\n");
916 skip_bits_long(gb, *num_bits_left); // bs_fill_bits
920 *num_bits_left -= ff_ps_read_data(ac->avctx, gb, &sbr->ps, *num_bits_left);
922 av_log_missing_feature(ac->avctx, "Parametric Stereo", 0);
923 skip_bits_long(gb, *num_bits_left); // bs_fill_bits
929 av_log_missing_feature(ac->avctx, "Reserved SBR extensions", 1);
930 skip_bits_long(gb, *num_bits_left); // bs_fill_bits
936 static int read_sbr_single_channel_element(AACContext *ac,
937 SpectralBandReplication *sbr,
940 if (get_bits1(gb)) // bs_data_extra
941 skip_bits(gb, 4); // bs_reserved
943 if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
945 read_sbr_dtdf(sbr, gb, &sbr->data[0]);
946 read_sbr_invf(sbr, gb, &sbr->data[0]);
947 read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
948 read_sbr_noise(sbr, gb, &sbr->data[0], 0);
950 if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
951 get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
956 static int read_sbr_channel_pair_element(AACContext *ac,
957 SpectralBandReplication *sbr,
960 if (get_bits1(gb)) // bs_data_extra
961 skip_bits(gb, 8); // bs_reserved
963 if ((sbr->bs_coupling = get_bits1(gb))) {
964 if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]))
966 copy_sbr_grid(&sbr->data[1], &sbr->data[0]);
967 read_sbr_dtdf(sbr, gb, &sbr->data[0]);
968 read_sbr_dtdf(sbr, gb, &sbr->data[1]);
969 read_sbr_invf(sbr, gb, &sbr->data[0]);
970 memcpy(sbr->data[1].bs_invf_mode[1], sbr->data[1].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
971 memcpy(sbr->data[1].bs_invf_mode[0], sbr->data[0].bs_invf_mode[0], sizeof(sbr->data[1].bs_invf_mode[0]));
972 read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
973 read_sbr_noise(sbr, gb, &sbr->data[0], 0);
974 read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
975 read_sbr_noise(sbr, gb, &sbr->data[1], 1);
977 if (read_sbr_grid(ac, sbr, gb, &sbr->data[0]) ||
978 read_sbr_grid(ac, sbr, gb, &sbr->data[1]))
980 read_sbr_dtdf(sbr, gb, &sbr->data[0]);
981 read_sbr_dtdf(sbr, gb, &sbr->data[1]);
982 read_sbr_invf(sbr, gb, &sbr->data[0]);
983 read_sbr_invf(sbr, gb, &sbr->data[1]);
984 read_sbr_envelope(sbr, gb, &sbr->data[0], 0);
985 read_sbr_envelope(sbr, gb, &sbr->data[1], 1);
986 read_sbr_noise(sbr, gb, &sbr->data[0], 0);
987 read_sbr_noise(sbr, gb, &sbr->data[1], 1);
990 if ((sbr->data[0].bs_add_harmonic_flag = get_bits1(gb)))
991 get_bits1_vector(gb, sbr->data[0].bs_add_harmonic, sbr->n[1]);
992 if ((sbr->data[1].bs_add_harmonic_flag = get_bits1(gb)))
993 get_bits1_vector(gb, sbr->data[1].bs_add_harmonic, sbr->n[1]);
998 static unsigned int read_sbr_data(AACContext *ac, SpectralBandReplication *sbr,
999 GetBitContext *gb, int id_aac)
1001 unsigned int cnt = get_bits_count(gb);
1003 if (id_aac == TYPE_SCE || id_aac == TYPE_CCE) {
1004 if (read_sbr_single_channel_element(ac, sbr, gb)) {
1006 return get_bits_count(gb) - cnt;
1008 } else if (id_aac == TYPE_CPE) {
1009 if (read_sbr_channel_pair_element(ac, sbr, gb)) {
1011 return get_bits_count(gb) - cnt;
1014 av_log(ac->avctx, AV_LOG_ERROR,
1015 "Invalid bitstream - cannot apply SBR to element type %d\n", id_aac);
1017 return get_bits_count(gb) - cnt;
1019 if (get_bits1(gb)) { // bs_extended_data
1020 int num_bits_left = get_bits(gb, 4); // bs_extension_size
1021 if (num_bits_left == 15)
1022 num_bits_left += get_bits(gb, 8); // bs_esc_count
1024 num_bits_left <<= 3;
1025 while (num_bits_left > 7) {
1027 read_sbr_extension(ac, sbr, gb, get_bits(gb, 2), &num_bits_left); // bs_extension_id
1029 if (num_bits_left < 0) {
1030 av_log(ac->avctx, AV_LOG_ERROR, "SBR Extension over read.\n");
1032 if (num_bits_left > 0)
1033 skip_bits(gb, num_bits_left);
1036 return get_bits_count(gb) - cnt;
1039 static void sbr_reset(AACContext *ac, SpectralBandReplication *sbr)
1042 err = sbr_make_f_master(ac, sbr, &sbr->spectrum_params);
1044 err = sbr_make_f_derived(ac, sbr);
1046 av_log(ac->avctx, AV_LOG_ERROR,
1047 "SBR reset failed. Switching SBR to pure upsampling mode.\n");
1053 * Decode Spectral Band Replication extension data; reference: table 4.55.
1055 * @param crc flag indicating the presence of CRC checksum
1056 * @param cnt length of TYPE_FIL syntactic element in bytes
1058 * @return Returns number of bytes consumed from the TYPE_FIL element.
1060 int ff_decode_sbr_extension(AACContext *ac, SpectralBandReplication *sbr,
1061 GetBitContext *gb_host, int crc, int cnt, int id_aac)
1063 unsigned int num_sbr_bits = 0, num_align_bits;
1064 unsigned bytes_read;
1065 GetBitContext gbc = *gb_host, *gb = &gbc;
1066 skip_bits_long(gb_host, cnt*8 - 4);
1070 if (!sbr->sample_rate)
1071 sbr->sample_rate = 2 * ac->oc[1].m4ac.sample_rate; //TODO use the nominal sample rate for arbitrary sample rate support
1072 if (!ac->oc[1].m4ac.ext_sample_rate)
1073 ac->oc[1].m4ac.ext_sample_rate = 2 * ac->oc[1].m4ac.sample_rate;
1076 skip_bits(gb, 10); // bs_sbr_crc_bits; TODO - implement CRC check
1080 //Save some state from the previous frame.
1081 sbr->kx[0] = sbr->kx[1];
1082 sbr->m[0] = sbr->m[1];
1083 sbr->kx_and_m_pushed = 1;
1086 if (get_bits1(gb)) // bs_header_flag
1087 num_sbr_bits += read_sbr_header(sbr, gb);
1093 num_sbr_bits += read_sbr_data(ac, sbr, gb, id_aac);
1095 num_align_bits = ((cnt << 3) - 4 - num_sbr_bits) & 7;
1096 bytes_read = ((num_sbr_bits + num_align_bits + 4) >> 3);
1098 if (bytes_read > cnt) {
1099 av_log(ac->avctx, AV_LOG_ERROR,
1100 "Expected to read %d SBR bytes actually read %d.\n", cnt, bytes_read);
1105 /// Dequantization and stereo decoding (14496-3 sp04 p203)
1106 static void sbr_dequant(SpectralBandReplication *sbr, int id_aac)
1111 if (id_aac == TYPE_CPE && sbr->bs_coupling) {
1112 float alpha = sbr->data[0].bs_amp_res ? 1.0f : 0.5f;
1113 float pan_offset = sbr->data[0].bs_amp_res ? 12.0f : 24.0f;
1114 for (e = 1; e <= sbr->data[0].bs_num_env; e++) {
1115 for (k = 0; k < sbr->n[sbr->data[0].bs_freq_res[e]]; k++) {
1116 float temp1 = exp2f(sbr->data[0].env_facs[e][k] * alpha + 7.0f);
1117 float temp2 = exp2f((pan_offset - sbr->data[1].env_facs[e][k]) * alpha);
1118 float fac = temp1 / (1.0f + temp2);
1119 sbr->data[0].env_facs[e][k] = fac;
1120 sbr->data[1].env_facs[e][k] = fac * temp2;
1123 for (e = 1; e <= sbr->data[0].bs_num_noise; e++) {
1124 for (k = 0; k < sbr->n_q; k++) {
1125 float temp1 = exp2f(NOISE_FLOOR_OFFSET - sbr->data[0].noise_facs[e][k] + 1);
1126 float temp2 = exp2f(12 - sbr->data[1].noise_facs[e][k]);
1127 float fac = temp1 / (1.0f + temp2);
1128 sbr->data[0].noise_facs[e][k] = fac;
1129 sbr->data[1].noise_facs[e][k] = fac * temp2;
1132 } else { // SCE or one non-coupled CPE
1133 for (ch = 0; ch < (id_aac == TYPE_CPE) + 1; ch++) {
1134 float alpha = sbr->data[ch].bs_amp_res ? 1.0f : 0.5f;
1135 for (e = 1; e <= sbr->data[ch].bs_num_env; e++)
1136 for (k = 0; k < sbr->n[sbr->data[ch].bs_freq_res[e]]; k++)
1137 sbr->data[ch].env_facs[e][k] =
1138 exp2f(alpha * sbr->data[ch].env_facs[e][k] + 6.0f);
1139 for (e = 1; e <= sbr->data[ch].bs_num_noise; e++)
1140 for (k = 0; k < sbr->n_q; k++)
1141 sbr->data[ch].noise_facs[e][k] =
1142 exp2f(NOISE_FLOOR_OFFSET - sbr->data[ch].noise_facs[e][k]);
1148 * Analysis QMF Bank (14496-3 sp04 p206)
1150 * @param x pointer to the beginning of the first sample window
1151 * @param W array of complex-valued samples split into subbands
1153 static void sbr_qmf_analysis(DSPContext *dsp, FFTContext *mdct,
1154 SBRDSPContext *sbrdsp, const float *in, float *x,
1155 float z[320], float W[2][32][32][2], int buf_idx)
1158 memcpy(x , x+1024, (320-32)*sizeof(x[0]));
1159 memcpy(x+288, in, 1024*sizeof(x[0]));
1160 for (i = 0; i < 32; i++) { // numTimeSlots*RATE = 16*2 as 960 sample frames
1161 // are not supported
1162 dsp->vector_fmul_reverse(z, sbr_qmf_window_ds, x, 320);
1164 sbrdsp->qmf_pre_shuffle(z);
1165 mdct->imdct_half(mdct, z, z+64);
1166 sbrdsp->qmf_post_shuffle(W[buf_idx][i], z);
1172 * Synthesis QMF Bank (14496-3 sp04 p206) and Downsampled Synthesis QMF Bank
1173 * (14496-3 sp04 p206)
1175 static void sbr_qmf_synthesis(DSPContext *dsp, FFTContext *mdct,
1176 SBRDSPContext *sbrdsp, AVFloatDSPContext *fdsp,
1177 float *out, float X[2][38][64],
1178 float mdct_buf[2][64],
1179 float *v0, int *v_off, const unsigned int div)
1182 const float *sbr_qmf_window = div ? sbr_qmf_window_ds : sbr_qmf_window_us;
1183 const int step = 128 >> div;
1185 for (i = 0; i < 32; i++) {
1186 if (*v_off < step) {
1187 int saved_samples = (1280 - 128) >> div;
1188 memcpy(&v0[SBR_SYNTHESIS_BUF_SIZE - saved_samples], v0, saved_samples * sizeof(float));
1189 *v_off = SBR_SYNTHESIS_BUF_SIZE - saved_samples - step;
1195 for (n = 0; n < 32; n++) {
1196 X[0][i][ n] = -X[0][i][n];
1197 X[0][i][32+n] = X[1][i][31-n];
1199 mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1200 sbrdsp->qmf_deint_neg(v, mdct_buf[0]);
1202 sbrdsp->neg_odd_64(X[1][i]);
1203 mdct->imdct_half(mdct, mdct_buf[0], X[0][i]);
1204 mdct->imdct_half(mdct, mdct_buf[1], X[1][i]);
1205 sbrdsp->qmf_deint_bfly(v, mdct_buf[1], mdct_buf[0]);
1207 fdsp->vector_fmul (out, v , sbr_qmf_window , 64 >> div);
1208 dsp->vector_fmul_add(out, v + ( 192 >> div), sbr_qmf_window + ( 64 >> div), out , 64 >> div);
1209 dsp->vector_fmul_add(out, v + ( 256 >> div), sbr_qmf_window + (128 >> div), out , 64 >> div);
1210 dsp->vector_fmul_add(out, v + ( 448 >> div), sbr_qmf_window + (192 >> div), out , 64 >> div);
1211 dsp->vector_fmul_add(out, v + ( 512 >> div), sbr_qmf_window + (256 >> div), out , 64 >> div);
1212 dsp->vector_fmul_add(out, v + ( 704 >> div), sbr_qmf_window + (320 >> div), out , 64 >> div);
1213 dsp->vector_fmul_add(out, v + ( 768 >> div), sbr_qmf_window + (384 >> div), out , 64 >> div);
1214 dsp->vector_fmul_add(out, v + ( 960 >> div), sbr_qmf_window + (448 >> div), out , 64 >> div);
1215 dsp->vector_fmul_add(out, v + (1024 >> div), sbr_qmf_window + (512 >> div), out , 64 >> div);
1216 dsp->vector_fmul_add(out, v + (1216 >> div), sbr_qmf_window + (576 >> div), out , 64 >> div);
1221 /** High Frequency Generation (14496-3 sp04 p214+) and Inverse Filtering
1222 * (14496-3 sp04 p214)
1223 * Warning: This routine does not seem numerically stable.
1225 static void sbr_hf_inverse_filter(SBRDSPContext *dsp,
1226 float (*alpha0)[2], float (*alpha1)[2],
1227 const float X_low[32][40][2], int k0)
1230 for (k = 0; k < k0; k++) {
1231 LOCAL_ALIGNED_16(float, phi, [3], [2][2]);
1234 dsp->autocorrelate(X_low[k], phi);
1236 dk = phi[2][1][0] * phi[1][0][0] -
1237 (phi[1][1][0] * phi[1][1][0] + phi[1][1][1] * phi[1][1][1]) / 1.000001f;
1243 float temp_real, temp_im;
1244 temp_real = phi[0][0][0] * phi[1][1][0] -
1245 phi[0][0][1] * phi[1][1][1] -
1246 phi[0][1][0] * phi[1][0][0];
1247 temp_im = phi[0][0][0] * phi[1][1][1] +
1248 phi[0][0][1] * phi[1][1][0] -
1249 phi[0][1][1] * phi[1][0][0];
1251 alpha1[k][0] = temp_real / dk;
1252 alpha1[k][1] = temp_im / dk;
1255 if (!phi[1][0][0]) {
1259 float temp_real, temp_im;
1260 temp_real = phi[0][0][0] + alpha1[k][0] * phi[1][1][0] +
1261 alpha1[k][1] * phi[1][1][1];
1262 temp_im = phi[0][0][1] + alpha1[k][1] * phi[1][1][0] -
1263 alpha1[k][0] * phi[1][1][1];
1265 alpha0[k][0] = -temp_real / phi[1][0][0];
1266 alpha0[k][1] = -temp_im / phi[1][0][0];
1269 if (alpha1[k][0] * alpha1[k][0] + alpha1[k][1] * alpha1[k][1] >= 16.0f ||
1270 alpha0[k][0] * alpha0[k][0] + alpha0[k][1] * alpha0[k][1] >= 16.0f) {
1279 /// Chirp Factors (14496-3 sp04 p214)
1280 static void sbr_chirp(SpectralBandReplication *sbr, SBRData *ch_data)
1284 static const float bw_tab[] = { 0.0f, 0.75f, 0.9f, 0.98f };
1286 for (i = 0; i < sbr->n_q; i++) {
1287 if (ch_data->bs_invf_mode[0][i] + ch_data->bs_invf_mode[1][i] == 1) {
1290 new_bw = bw_tab[ch_data->bs_invf_mode[0][i]];
1292 if (new_bw < ch_data->bw_array[i]) {
1293 new_bw = 0.75f * new_bw + 0.25f * ch_data->bw_array[i];
1295 new_bw = 0.90625f * new_bw + 0.09375f * ch_data->bw_array[i];
1296 ch_data->bw_array[i] = new_bw < 0.015625f ? 0.0f : new_bw;
1300 /// Generate the subband filtered lowband
1301 static int sbr_lf_gen(AACContext *ac, SpectralBandReplication *sbr,
1302 float X_low[32][40][2], const float W[2][32][32][2],
1306 const int t_HFGen = 8;
1308 memset(X_low, 0, 32*sizeof(*X_low));
1309 for (k = 0; k < sbr->kx[1]; k++) {
1310 for (i = t_HFGen; i < i_f + t_HFGen; i++) {
1311 X_low[k][i][0] = W[buf_idx][i - t_HFGen][k][0];
1312 X_low[k][i][1] = W[buf_idx][i - t_HFGen][k][1];
1315 buf_idx = 1-buf_idx;
1316 for (k = 0; k < sbr->kx[0]; k++) {
1317 for (i = 0; i < t_HFGen; i++) {
1318 X_low[k][i][0] = W[buf_idx][i + i_f - t_HFGen][k][0];
1319 X_low[k][i][1] = W[buf_idx][i + i_f - t_HFGen][k][1];
1325 /// High Frequency Generator (14496-3 sp04 p215)
1326 static int sbr_hf_gen(AACContext *ac, SpectralBandReplication *sbr,
1327 float X_high[64][40][2], const float X_low[32][40][2],
1328 const float (*alpha0)[2], const float (*alpha1)[2],
1329 const float bw_array[5], const uint8_t *t_env,
1335 for (j = 0; j < sbr->num_patches; j++) {
1336 for (x = 0; x < sbr->patch_num_subbands[j]; x++, k++) {
1337 const int p = sbr->patch_start_subband[j] + x;
1338 while (g <= sbr->n_q && k >= sbr->f_tablenoise[g])
1343 av_log(ac->avctx, AV_LOG_ERROR,
1344 "ERROR : no subband found for frequency %d\n", k);
1348 sbr->dsp.hf_gen(X_high[k] + ENVELOPE_ADJUSTMENT_OFFSET,
1349 X_low[p] + ENVELOPE_ADJUSTMENT_OFFSET,
1350 alpha0[p], alpha1[p], bw_array[g],
1351 2 * t_env[0], 2 * t_env[bs_num_env]);
1354 if (k < sbr->m[1] + sbr->kx[1])
1355 memset(X_high + k, 0, (sbr->m[1] + sbr->kx[1] - k) * sizeof(*X_high));
1360 /// Generate the subband filtered lowband
1361 static int sbr_x_gen(SpectralBandReplication *sbr, float X[2][38][64],
1362 const float Y0[38][64][2], const float Y1[38][64][2],
1363 const float X_low[32][40][2], int ch)
1367 const int i_Temp = FFMAX(2*sbr->data[ch].t_env_num_env_old - i_f, 0);
1368 memset(X, 0, 2*sizeof(*X));
1369 for (k = 0; k < sbr->kx[0]; k++) {
1370 for (i = 0; i < i_Temp; i++) {
1371 X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1372 X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1375 for (; k < sbr->kx[0] + sbr->m[0]; k++) {
1376 for (i = 0; i < i_Temp; i++) {
1377 X[0][i][k] = Y0[i + i_f][k][0];
1378 X[1][i][k] = Y0[i + i_f][k][1];
1382 for (k = 0; k < sbr->kx[1]; k++) {
1383 for (i = i_Temp; i < 38; i++) {
1384 X[0][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][0];
1385 X[1][i][k] = X_low[k][i + ENVELOPE_ADJUSTMENT_OFFSET][1];
1388 for (; k < sbr->kx[1] + sbr->m[1]; k++) {
1389 for (i = i_Temp; i < i_f; i++) {
1390 X[0][i][k] = Y1[i][k][0];
1391 X[1][i][k] = Y1[i][k][1];
1397 /** High Frequency Adjustment (14496-3 sp04 p217) and Mapping
1398 * (14496-3 sp04 p217)
1400 static int sbr_mapping(AACContext *ac, SpectralBandReplication *sbr,
1401 SBRData *ch_data, int e_a[2])
1405 memset(ch_data->s_indexmapped[1], 0, 7*sizeof(ch_data->s_indexmapped[1]));
1406 for (e = 0; e < ch_data->bs_num_env; e++) {
1407 const unsigned int ilim = sbr->n[ch_data->bs_freq_res[e + 1]];
1408 uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1411 if (sbr->kx[1] != table[0]) {
1412 av_log(ac->avctx, AV_LOG_ERROR, "kx != f_table{high,low}[0]. "
1413 "Derived frequency tables were not regenerated.\n");
1417 for (i = 0; i < ilim; i++)
1418 for (m = table[i]; m < table[i + 1]; m++)
1419 sbr->e_origmapped[e][m - sbr->kx[1]] = ch_data->env_facs[e+1][i];
1421 // ch_data->bs_num_noise > 1 => 2 noise floors
1422 k = (ch_data->bs_num_noise > 1) && (ch_data->t_env[e] >= ch_data->t_q[1]);
1423 for (i = 0; i < sbr->n_q; i++)
1424 for (m = sbr->f_tablenoise[i]; m < sbr->f_tablenoise[i + 1]; m++)
1425 sbr->q_mapped[e][m - sbr->kx[1]] = ch_data->noise_facs[k+1][i];
1427 for (i = 0; i < sbr->n[1]; i++) {
1428 if (ch_data->bs_add_harmonic_flag) {
1429 const unsigned int m_midpoint =
1430 (sbr->f_tablehigh[i] + sbr->f_tablehigh[i + 1]) >> 1;
1432 ch_data->s_indexmapped[e + 1][m_midpoint - sbr->kx[1]] = ch_data->bs_add_harmonic[i] *
1433 (e >= e_a[1] || (ch_data->s_indexmapped[0][m_midpoint - sbr->kx[1]] == 1));
1437 for (i = 0; i < ilim; i++) {
1438 int additional_sinusoid_present = 0;
1439 for (m = table[i]; m < table[i + 1]; m++) {
1440 if (ch_data->s_indexmapped[e + 1][m - sbr->kx[1]]) {
1441 additional_sinusoid_present = 1;
1445 memset(&sbr->s_mapped[e][table[i] - sbr->kx[1]], additional_sinusoid_present,
1446 (table[i + 1] - table[i]) * sizeof(sbr->s_mapped[e][0]));
1450 memcpy(ch_data->s_indexmapped[0], ch_data->s_indexmapped[ch_data->bs_num_env], sizeof(ch_data->s_indexmapped[0]));
1454 /// Estimation of current envelope (14496-3 sp04 p218)
1455 static void sbr_env_estimate(float (*e_curr)[48], float X_high[64][40][2],
1456 SpectralBandReplication *sbr, SBRData *ch_data)
1459 int kx1 = sbr->kx[1];
1461 if (sbr->bs_interpol_freq) {
1462 for (e = 0; e < ch_data->bs_num_env; e++) {
1463 const float recip_env_size = 0.5f / (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1464 int ilb = ch_data->t_env[e] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1465 int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1467 for (m = 0; m < sbr->m[1]; m++) {
1468 float sum = sbr->dsp.sum_square(X_high[m+kx1] + ilb, iub - ilb);
1469 e_curr[e][m] = sum * recip_env_size;
1475 for (e = 0; e < ch_data->bs_num_env; e++) {
1476 const int env_size = 2 * (ch_data->t_env[e + 1] - ch_data->t_env[e]);
1477 int ilb = ch_data->t_env[e] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1478 int iub = ch_data->t_env[e + 1] * 2 + ENVELOPE_ADJUSTMENT_OFFSET;
1479 const uint16_t *table = ch_data->bs_freq_res[e + 1] ? sbr->f_tablehigh : sbr->f_tablelow;
1481 for (p = 0; p < sbr->n[ch_data->bs_freq_res[e + 1]]; p++) {
1483 const int den = env_size * (table[p + 1] - table[p]);
1485 for (k = table[p]; k < table[p + 1]; k++) {
1486 sum += sbr->dsp.sum_square(X_high[k] + ilb, iub - ilb);
1489 for (k = table[p]; k < table[p + 1]; k++) {
1490 e_curr[e][k - kx1] = sum;
1498 * Calculation of levels of additional HF signal components (14496-3 sp04 p219)
1499 * and Calculation of gain (14496-3 sp04 p219)
1501 static void sbr_gain_calc(AACContext *ac, SpectralBandReplication *sbr,
1502 SBRData *ch_data, const int e_a[2])
1505 // max gain limits : -3dB, 0dB, 3dB, inf dB (limiter off)
1506 static const float limgain[4] = { 0.70795, 1.0, 1.41254, 10000000000 };
1508 for (e = 0; e < ch_data->bs_num_env; e++) {
1509 int delta = !((e == e_a[1]) || (e == e_a[0]));
1510 for (k = 0; k < sbr->n_lim; k++) {
1511 float gain_boost, gain_max;
1512 float sum[2] = { 0.0f, 0.0f };
1513 for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1514 const float temp = sbr->e_origmapped[e][m] / (1.0f + sbr->q_mapped[e][m]);
1515 sbr->q_m[e][m] = sqrtf(temp * sbr->q_mapped[e][m]);
1516 sbr->s_m[e][m] = sqrtf(temp * ch_data->s_indexmapped[e + 1][m]);
1517 if (!sbr->s_mapped[e][m]) {
1518 sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] /
1519 ((1.0f + sbr->e_curr[e][m]) *
1520 (1.0f + sbr->q_mapped[e][m] * delta)));
1522 sbr->gain[e][m] = sqrtf(sbr->e_origmapped[e][m] * sbr->q_mapped[e][m] /
1523 ((1.0f + sbr->e_curr[e][m]) *
1524 (1.0f + sbr->q_mapped[e][m])));
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];
1531 gain_max = limgain[sbr->bs_limiter_gains] * sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
1532 gain_max = FFMIN(100000.f, gain_max);
1533 for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1534 float q_m_max = sbr->q_m[e][m] * gain_max / sbr->gain[e][m];
1535 sbr->q_m[e][m] = FFMIN(sbr->q_m[e][m], q_m_max);
1536 sbr->gain[e][m] = FFMIN(sbr->gain[e][m], gain_max);
1538 sum[0] = sum[1] = 0.0f;
1539 for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1540 sum[0] += sbr->e_origmapped[e][m];
1541 sum[1] += sbr->e_curr[e][m] * sbr->gain[e][m] * sbr->gain[e][m]
1542 + sbr->s_m[e][m] * sbr->s_m[e][m]
1543 + (delta && !sbr->s_m[e][m]) * sbr->q_m[e][m] * sbr->q_m[e][m];
1545 gain_boost = sqrtf((FLT_EPSILON + sum[0]) / (FLT_EPSILON + sum[1]));
1546 gain_boost = FFMIN(1.584893192f, gain_boost);
1547 for (m = sbr->f_tablelim[k] - sbr->kx[1]; m < sbr->f_tablelim[k + 1] - sbr->kx[1]; m++) {
1548 sbr->gain[e][m] *= gain_boost;
1549 sbr->q_m[e][m] *= gain_boost;
1550 sbr->s_m[e][m] *= gain_boost;
1556 /// Assembling HF Signals (14496-3 sp04 p220)
1557 static void sbr_hf_assemble(float Y1[38][64][2],
1558 const float X_high[64][40][2],
1559 SpectralBandReplication *sbr, SBRData *ch_data,
1563 const int h_SL = 4 * !sbr->bs_smoothing_mode;
1564 const int kx = sbr->kx[1];
1565 const int m_max = sbr->m[1];
1566 static const float h_smooth[5] = {
1573 static const int8_t phi[2][4] = {
1574 { 1, 0, -1, 0}, // real
1575 { 0, 1, 0, -1}, // imaginary
1577 float (*g_temp)[48] = ch_data->g_temp, (*q_temp)[48] = ch_data->q_temp;
1578 int indexnoise = ch_data->f_indexnoise;
1579 int indexsine = ch_data->f_indexsine;
1582 for (i = 0; i < h_SL; i++) {
1583 memcpy(g_temp[i + 2*ch_data->t_env[0]], sbr->gain[0], m_max * sizeof(sbr->gain[0][0]));
1584 memcpy(q_temp[i + 2*ch_data->t_env[0]], sbr->q_m[0], m_max * sizeof(sbr->q_m[0][0]));
1587 memcpy(g_temp[2*ch_data->t_env[0]], g_temp[2*ch_data->t_env_num_env_old], 4*sizeof(g_temp[0]));
1588 memcpy(q_temp[2*ch_data->t_env[0]], q_temp[2*ch_data->t_env_num_env_old], 4*sizeof(q_temp[0]));
1591 for (e = 0; e < ch_data->bs_num_env; e++) {
1592 for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
1593 memcpy(g_temp[h_SL + i], sbr->gain[e], m_max * sizeof(sbr->gain[0][0]));
1594 memcpy(q_temp[h_SL + i], sbr->q_m[e], m_max * sizeof(sbr->q_m[0][0]));
1598 for (e = 0; e < ch_data->bs_num_env; e++) {
1599 for (i = 2 * ch_data->t_env[e]; i < 2 * ch_data->t_env[e + 1]; i++) {
1600 int phi_sign = (1 - 2*(kx & 1));
1601 LOCAL_ALIGNED_16(float, g_filt_tab, [48]);
1602 LOCAL_ALIGNED_16(float, q_filt_tab, [48]);
1603 float *g_filt, *q_filt;
1605 if (h_SL && e != e_a[0] && e != e_a[1]) {
1606 g_filt = g_filt_tab;
1607 q_filt = q_filt_tab;
1608 for (m = 0; m < m_max; m++) {
1609 const int idx1 = i + h_SL;
1612 for (j = 0; j <= h_SL; j++) {
1613 g_filt[m] += g_temp[idx1 - j][m] * h_smooth[j];
1614 q_filt[m] += q_temp[idx1 - j][m] * h_smooth[j];
1618 g_filt = g_temp[i + h_SL];
1622 sbr->dsp.hf_g_filt(Y1[i] + kx, X_high + kx, g_filt, m_max,
1623 i + ENVELOPE_ADJUSTMENT_OFFSET);
1625 if (e != e_a[0] && e != e_a[1]) {
1626 sbr->dsp.hf_apply_noise[indexsine](Y1[i] + kx, sbr->s_m[e],
1630 for (m = 0; m < m_max; m++) {
1632 sbr->s_m[e][m] * phi[0][indexsine];
1634 sbr->s_m[e][m] * (phi[1][indexsine] * phi_sign);
1635 phi_sign = -phi_sign;
1638 indexnoise = (indexnoise + m_max) & 0x1ff;
1639 indexsine = (indexsine + 1) & 3;
1642 ch_data->f_indexnoise = indexnoise;
1643 ch_data->f_indexsine = indexsine;
1646 void ff_sbr_apply(AACContext *ac, SpectralBandReplication *sbr, int id_aac,
1649 int downsampled = ac->oc[1].m4ac.ext_sample_rate < sbr->sample_rate;
1651 int nch = (id_aac == TYPE_CPE) ? 2 : 1;
1654 if (!sbr->kx_and_m_pushed) {
1655 sbr->kx[0] = sbr->kx[1];
1656 sbr->m[0] = sbr->m[1];
1658 sbr->kx_and_m_pushed = 0;
1662 sbr_dequant(sbr, id_aac);
1664 for (ch = 0; ch < nch; ch++) {
1665 /* decode channel */
1666 sbr_qmf_analysis(&ac->dsp, &sbr->mdct_ana, &sbr->dsp, ch ? R : L, sbr->data[ch].analysis_filterbank_samples,
1667 (float*)sbr->qmf_filter_scratch,
1668 sbr->data[ch].W, sbr->data[ch].Ypos);
1669 sbr_lf_gen(ac, sbr, sbr->X_low, sbr->data[ch].W, sbr->data[ch].Ypos);
1670 sbr->data[ch].Ypos ^= 1;
1672 sbr_hf_inverse_filter(&sbr->dsp, sbr->alpha0, sbr->alpha1, sbr->X_low, sbr->k[0]);
1673 sbr_chirp(sbr, &sbr->data[ch]);
1674 sbr_hf_gen(ac, sbr, sbr->X_high, sbr->X_low, sbr->alpha0, sbr->alpha1,
1675 sbr->data[ch].bw_array, sbr->data[ch].t_env,
1676 sbr->data[ch].bs_num_env);
1679 err = sbr_mapping(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1681 sbr_env_estimate(sbr->e_curr, sbr->X_high, sbr, &sbr->data[ch]);
1682 sbr_gain_calc(ac, sbr, &sbr->data[ch], sbr->data[ch].e_a);
1683 sbr_hf_assemble(sbr->data[ch].Y[sbr->data[ch].Ypos],
1684 sbr->X_high, sbr, &sbr->data[ch],
1690 sbr_x_gen(sbr, sbr->X[ch],
1691 sbr->data[ch].Y[1-sbr->data[ch].Ypos],
1692 sbr->data[ch].Y[ sbr->data[ch].Ypos],
1696 if (ac->oc[1].m4ac.ps == 1) {
1697 if (sbr->ps.start) {
1698 ff_ps_apply(ac->avctx, &sbr->ps, sbr->X[0], sbr->X[1], sbr->kx[1] + sbr->m[1]);
1700 memcpy(sbr->X[1], sbr->X[0], sizeof(sbr->X[0]));
1705 sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, &sbr->dsp, &ac->fdsp,
1706 L, sbr->X[0], sbr->qmf_filter_scratch,
1707 sbr->data[0].synthesis_filterbank_samples,
1708 &sbr->data[0].synthesis_filterbank_samples_offset,
1711 sbr_qmf_synthesis(&ac->dsp, &sbr->mdct, &sbr->dsp, &ac->fdsp,
1712 R, sbr->X[1], sbr->qmf_filter_scratch,
1713 sbr->data[1].synthesis_filterbank_samples,
1714 &sbr->data[1].synthesis_filterbank_samples_offset,